北山 丈二

Overcoming immune tolerance of tumor angiogenesis should be useful for adjuvant therapy of cancer. we hypothesized that vaccination with autologous endothelium would induce an autoimmune response targeting tumor angiogenesis. To test this concept, we immunized BALB/c mice with a vaccine of glutaraldehyde-fixed murine hepatic sinusoidal endothelial cells (HSEs) in a lung metastasis model of Colon-26 cancer. Vaccination with autologous HSEs induced both preventive and therapeutic anti-tumor immunity that significantly inhibited the development of metastases. ELISA revealed an immunoglobulin response involving IgM and IgG subclasses. These antibodies had a strong affinity for antigens of both murine and human endothelium, and lyzed endothelial cells in the CDC assay. Flow-cytometry and chromium-release cytotoxicity assay revealed a specific CTL response against endothelial cells, which were lyzed in an effector: target ratio-dependent manner. Neither antibodies nor CTLs reacted with Colon-26. The effect of autologous HSEs was more pronounced than that of xenogeneic human umbilical vein endothelial cells (HUVECs), which were tested in the same experimental setting. Our results suggest that vaccination with autologous endothelium can overcome peripheral tolerance of self-angiogenic antigens and therefore should be useful for adjuvant immunotherapy of cancer.

Introduction Lysophosphatidic acid (LPA) is a bioactive phospholipid with diverse effects on various cells. It interacts with at least three G-protein-coupled transmembrane receptors, namely LPA1, LPA2 and LPA3, whose expression in various tumours has not been fully characterized. In the present study we characterized the expression profile of LPA receptors in human breast cancer tissue and assessed the possible roles of each receptor. Methods The relative expression levels of each receptor's mRNA against - actin mRNA was examined in surgically resected invasive ductal carcinomas and normal gland tissue using real-time RT-PCR. LPA2 expression was also examined immunohistochemically using a rat anti-LPA2 monoclonal antibody. Results In 25 cases normal and cancer tissue contained LPA1 mRNA at similar levels, whereas the expression level of LPA2 mRNA was significantly increased in cancer tissue as compared with its normal counterpart (3479.0 +/- 426.6 versus 1287.3 +/- 466.8; P < 0.05). LPA3 was weakly expressed in both cancer and normal gland tissue. In 48 (57%) out of 84 cases, enhanced expression of LPA2 protein was confirmed in carcinoma cells as compared with normal mammary epithelium by immunohistochemistry. Over-expression of LPA2 was detected in 17 (45%) out of 38 premenopausal women, as compared with 31 (67%) out of 46 postmenopausal women, and the difference was statistically significant ( P < 0.05). Conclusion These findings suggest that upregulation of LPA2 may play a role in carcinogenesis, particularly in postmenopausal breast cancer.

Although peritoneal metastasis is an important factor determining the prognosis of patients with gastrointestinal cancer, the mechanisms have not yet been clearly defined. Human peritoneal mesothelial cells (HPMC) are the first line against disseminated tumor cells. Recent reports have shown that mesothelial cells are capable of secreting various cytokines and growth factors. In this study, we isolated human mesothelial cells from surgically resected omental tissue and examined the production and interaction of two major angiogenic factors, vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (FGF-2). Quiescent HPMC produced a considerable amount of VEGF at almost the same level as tumor cells. Interestingly, addition of FGF-2 to the culture significantly increased the mRNA synthesis and protein secretion of VEGF in a dose-dependent manner, as determined by Northern blot and ELISA. The addition of 0.5 ng/mL FGF-2 was enough to stimulate VEGF production, and the effect reached a plateau at 5 ng/mL. Reverse-transcribed polymerase chain reaction (RT-PCR) method clarified that the HPMC-derived VEGF consisted mostly of VEGF(121) and VEGF(165), which are both predominantly soluble forms. These data suggest that HPMC contribute to the development of metastases and the accumulation of malignant ascites due to the production of VEGF, especially in cancers that do not express enough amount of VEGF. (C) 2003 Elsevier Inc. All rights reserved.

Background: Epigallocatechin gallate (EGCG), the major component of tea polyphenol, has been reported to have various physiologic modulatory activities. Several reports also have shown that catechin has a protective effect against HIV infection, part of which is mediated by inhibiting virions to bind to the target cell surface. Objective: We investigated the effect of EGCG on the expression of CD4 molecules and on its ability to bind gp120, an envelope protein of HIV-1. Methods: Peripheral blood CD4(+) T cells were incubated in the presence of EGCG, and the expression of CD4 was evaluated by means of flow cytometry. The effect of EGCG on the antibody binding to CD4 was investigated by using a sandwich ELISA, and the effect on the gp120 binding to CD4 was analyzed by means of flow cytometry. Results: EGCG efficiently inhibited binding of anti-CD4 antibody to its corresponding antigen. This effect was mediated by the direct binding of EGCG to the CD4 molecule, with consequent inhibition of antibody binding, as well as gp120 binding. Conclusion: The present results suggest a potential preventive effect of EGCG on HIV-1 infection by modulating binding to CD4.

Background. Liver metastasis is an important factor determining prognosis in colorectal cancer. The objective of this study was to assess whether colorectal cancer cells in the drainage veins can be detected by measuring telomerase activity and its detection is correlated with liver metastasis. Methods. Telomeric repeat amplification protocol assay in combination with an immunomagnetic sorting was used for measuring telomerase activity of epithelial cells in blood samples collected from mesenteric (tumor-drainage) vein and peripheral vessels of 41 colorectal cancer patients. Telomerase activity was calculated as relative telomerase activity (RTA) against a control template and analyzed in terms of liver metastasis. Results. RTA of mesenteric blood samples was significantly higher in patients with liver metastasis. (60.8%; n = 7) than in those without metastasis (19.7%; n = 34; P = .019). The RTA of peripheral blood sample was also higher in patients with liver metastasis (26.8%) than in those without metastasis (11.1%; p = .17). Moreover, 57% of cases with liver metastasis exhibited a positive telomerase activity in mesenteric blood sample, whereas it was 18% in cases without metastasis. Conclusions. Our assay was proven to be a feasible method for detecting cancer cells in tumor-drainage veins. High telomerase activity of mesenteric blood samples reflected the existence of liver metastasis of colorectal cancer.

Although peritoneal metastasis is an important factor determining the prognosis of patients with gastrointestinal cancer, the mechanisms have not yet been clearly defined. Human peritoneal mesothelial cells (HPMC) are the first line against disseminated tumor cells. Recent reports have shown that mesothelial cells are capable of secreting various cytokines and growth factors. In this study, we isolated human mesothelial cells from surgically resected omental tissue and examined the production and interaction of two major angiogenic factors, vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (FGF-2). Quiescent HPMC produced a considerable amount of VEGF at almost the same level as tumor cells. Interestingly, addition of FGF-2 to the culture significantly increased the mRNA synthesis and protein secretion of VEGF in a dose-dependent manner, as determined by Northern blot and ELISA. The addition of 0.5 ng/mL FGF-2 was enough to stimulate VEGF production, and the effect reached a plateau at 5 ng/mL. Reverse-transcribed polymerase chain reaction (RT-PCR) method clarified that the HPMC-derived VEGF consisted mostly of VEGF(121) and VEGF(165), which are both predominantly soluble forms. These data suggest that HPMC contribute to the development of metastases and the accumulation of malignant ascites due to the production of VEGF, especially in cancers that do not express enough amount of VEGF. (C) 2003 Elsevier Inc. All rights reserved.

Background: Epigallocatechin gallate (EGCG), the major component of tea polyphenol, has been reported to have various physiologic modulatory activities. Several reports also have shown that catechin has a protective effect against HIV infection, part of which is mediated by inhibiting virions to bind to the target cell surface. Objective: We investigated the effect of EGCG on the expression of CD4 molecules and on its ability to bind gp120, an envelope protein of HIV-1. Methods: Peripheral blood CD4(+) T cells were incubated in the presence of EGCG, and the expression of CD4 was evaluated by means of flow cytometry. The effect of EGCG on the antibody binding to CD4 was investigated by using a sandwich ELISA, and the effect on the gp120 binding to CD4 was analyzed by means of flow cytometry. Results: EGCG efficiently inhibited binding of anti-CD4 antibody to its corresponding antigen. This effect was mediated by the direct binding of EGCG to the CD4 molecule, with consequent inhibition of antibody binding, as well as gp120 binding. Conclusion: The present results suggest a potential preventive effect of EGCG on HIV-1 infection by modulating binding to CD4.

Background. Liver metastasis is an important factor determining prognosis in colorectal cancer. The objective of this study was to assess whether colorectal cancer cells in the drainage veins can be detected by measuring telomerase activity and its detection is correlated with liver metastasis. Methods. Telomeric repeat amplification protocol assay in combination with an immunomagnetic sorting was used for measuring telomerase activity of epithelial cells in blood samples collected from mesenteric (tumor-drainage) vein and peripheral vessels of 41 colorectal cancer patients. Telomerase activity was calculated as relative telomerase activity (RTA) against a control template and analyzed in terms of liver metastasis. Results. RTA of mesenteric blood samples was significantly higher in patients with liver metastasis. (60.8%; n = 7) than in those without metastasis (19.7%; n = 34; P = .019). The RTA of peripheral blood sample was also higher in patients with liver metastasis (26.8%) than in those without metastasis (11.1%; p = .17). Moreover, 57% of cases with liver metastasis exhibited a positive telomerase activity in mesenteric blood sample, whereas it was 18% in cases without metastasis. Conclusions. Our assay was proven to be a feasible method for detecting cancer cells in tumor-drainage veins. High telomerase activity of mesenteric blood samples reflected the existence of liver metastasis of colorectal cancer.

Background/Aims: The EDG-2 (endothelial cell differentiation gene-2) has been characterized as one of the high-affinity receptors of lysophosphatidic acid: an extracellular lipid mediator which can induce tumor progression. Recent studies have revealed that EDG-2 plays an important role in various pathological events including cell proliferation and tumor development. The investigation of EDG-2 is thus considered important for eliciting the mechanism of tumorigenesis. However, in colorectal tissue, the clinical significance of EDG-2 expression remains unclear. In the current study, we examined the immunohistochemical expression of EDG-2 in colorectal mucosa and adenoma, and clarified its relation with the clinicopathological features. Methodology: One hundred and sixty-one colorectal polyps were resected endoscopically or surgically at our institute from 2000 to 2001. According to the degree of dysplasia, adenomas were grouped into two categories: low-grade (mild or moderate dysplasia) and high-grade (severe dysplasia or carcinoma in situ). We investigated EDG-2 expression by immunohistochemistry. Results: EDG-2 was expressed almost exclusively in the cytoplasm in colorectal normal mucosa and adenoma. EDG-2 expression in normal mucosa and adenoma was 8% and 76%, respectively. EDG-2 expression was increased in low-grade adenoma compared with that in normal mucosa (P < 0.001). EDG-2 expression was significantly greater in adenomas with larger diameters (P < 0.001). Conclusions: We demonstrated that EDG-2 expression was increased in the early stage of adenoma. A significant correlation between EDG-2 expression and the size - of the adenomas suggests that EDG-2 may play an important role in the growth of these adenomas.

Chemokines have been shown to be expressed in some malignant or precancerous tissues. However, the role of these chemokines on tumor development or progression is not clear. The expression patterns of chemokines in gastric cancer tissues were examined in 86 surgically resected samples using immunohistochemistry. Macrophage inflammatory protein-1 beta (MIP-1beta) was clearly detected in many gastric carcinoma cells. In most of the differentiated carcinomas, intracellular localization of MIP-1beta was detected in more than 5% of cancer cells, although the percentages of MIP-1beta-positive cells differed among each sample. Undifferentiated carcinomas showed contrasted staining pattern between solid type and non-solid (diffuse) type. MIP-1beta was totally absent in all the poorly differentiated carcinomas with solid type growth pattern (porl). In contrast, MIP-1beta was highly expressed in all of the non-solid type of poorly differentiated carcinoma (por2) and signet-ring cell carcinoma samples. In particular, MIP-1beta was strongly stained in carcinoma cells at the front of invasive lesions. In 43 diffuse type undifferentiated cancers, tumors with high expression of MIP-1beta exhibited significantly more lymph node metastasis. Our results suggest a possibility that MIP-1beta may be related to the scattering and invasion step of gastric carcinoma cells with undifferentiated phenotype.

We have recently reported that S1P (sphingosine-1-phosphate) differentially regulates cellular Rac activity and cell migration in either a positive or a negative direction via distinct G-protein-coupled receptor subtypes, i.e. S1P(1)/Edg1 (endothelial differentiation gene) and S1P(1)/Edg5 respectively, when each of the S1P receptor subtypes is expressed in CHO (Chinese-hamster ovary) cells. In B16F10 mouse melanoma cells, in which S1P(2), but not the other S1P-receptor subtypes, is endogenously expressed, S1P inhibited cell migration with concomitant inhibition of Rac and stimulation of RhoA in dose-dependent manners. Overexpression of S1P, in the melanoma cells resulted in potentiation of S1P inhibition of both Rac and cell migration. In contrast, overexpression of S1P(1) led to stimulation of cell migration, particularly at the lower S1P concentrations. Treatment of B16F10 cells with S1P inhibited lung metastasis 3 weeks after injection into mouse tail veins. Intriguingly, overexpression of S1P(2) greatly potentiated the inhibition of metastasis by S1P, whereas that of S1P(1) resulted in aggravation of metastasis. Suppression of cellular Rac activity by adenovirus-transduced expression of N(17)Rac, but not N(19)RhoA, strongly inhibited cell migration in vitro and lung metastasis in vivo. These results provide the first evidence that G-protein-coupled receptors could participate in the regulation of metastasis, in which ligand-dependent, subtype-specific regulation of the cellular Rac activity is probably critically involved as a mechanism.

We investigated mechanisms for inhibition of B16 melanoma cell migration and invasion by sphingosine-1-phosphate (S1P), which is the ligand for the Edg family G protein-coupled receptors and also implicated as an intracellular second messenger. S1P, dihydro-S1P, and sphingosylphosphorylcholine inhibited B16 cell migration and invasion with the relative potencies expected as S1P(2) receptor agonists. The S1P(2)-selective antagonist JTE013 completely abolished the responses to these agonists. In addition, JTE013 abrogated the inhibition by sphingosine, which is the S1P precursor but not an agonist for S1P receptors, indicating that the sphingosine effects were mediated via S1P(2) stimulation, most likely by S1P that was converted from sphingosine. S1P induced inhibition and activation, respectively, of Rac and RhoA in B16 cells, which were abrogated by JTE013. Adenovirus-mediated expression of N(17)Rac mimicked S1P inhibition of migration, whereas C3 toxin pretreatment, but not Rho kinase inhibitors, reversed the S1P inhibition. Overexpression of S1P(2) sensitized, and that of either S1P(1) or S1P(3) desensitized, B16 cells to S1P inhibition of Rac and migration. In JTE013-pretreated, S1P(3)-overexpressing B16 cells, S1P stimulated cellular RhoA but failed to inhibit either Rac or migration, indicating that RhoA stimulation itself is not sufficient for inhibition of migration. These results provide compelling evidence that endogenously expressed S1P(2) negatively regulates cell motility and invasion through ligand dependent reciprocal regulation of cellular Rac and RhoA activities. In the presence of JTE013, S1P instead stimulated Rac and migration in B16 cells that overexpress either S1P(1) or S1P(3), unveiling counteractions between S1P(2) and S1P(1) or S1P(3) chemotactic receptor.

Background/Aims: DPD (dihydropyrimidine. dehydrogenase) activity shows a correlation with 5-fluorouracil chemosensitivity. To quantify DPD activity is important for selection of chemosensitive cases of not only sporadic colorectal cancer but also rectal cancer with preoperative radiotherapy. However, it is not cost-effective. We investigated the relation between the immunohistochemical expression pattern of DPD and its activity in rectal cancer treated with radiotherapy, and compared the immunohistochemical. DPD expression pattern of preradiation biopsy specimens with that of resected tissues. Methodology DPD expression pattern of preradiation biopsy specimens were compared with that of resected. tissues. Eighteen colorectal cancer tissue samples were obtained after surgery from October 2000 to January 2001. DPD activity was quantified by sandwich enzyme-linked immunosorbent assay. The streptoavidin-biotin peroxidase complex technique was used for, the immunohistochemical expression pattern. Results: DPD was stained in the cytoplasm of cancer cells. There was a significant correlation between the immunohistochemical expression pattern of DPD and its activity in tumor tissue treated with or without radiotherapy. The immunohistochemical expression pattern of preradiation biopsy specimens was almost the same as that of resected tissues. Conclusions: The immunohistochemical expression pattern of DPD correlated with its activity in tumor tissue treated with preoperative radiotherapy. Immunohistochemical evaluation is considered to be an effective method of predicting the sensitivity to 5-fluorouracil of rectal cancer treated with preoperative radiotherapy.

The identification of predictive indicators of radiosensitivity is extremely useful in selecting patients suited for preoperative radiotherapy and avoiding unnecessary preoperative treatment. In this study, we evaluated the possible role of the immunohistochemical expression pattern of p53 and Ku70 protein in determining tumor radiosensitivity in rectal cancer before preoperative irradiation. We examined pretreatment biopsy materials from 111 patients by immunohistochemistry. The expression pattern of p53 and Ku70 was evaluated for association with tumor radiosensitivity, which was defined according to the criteria of the Japanese Research Society for Cancer of the Colon and Rectum. There was a significant correlation between the expression pattern of p53 and tumor radiosensitivity (P=0.045); Ku70 and tumor radiosensitivity (P<0.001); and the combination of p53 and Ku70, and tumor radiosensitivity (P<0.001). The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy in both p53 and Ku70-positive cases for radioresistance were all superior to those of the group positive for p53 alone. In conclusion the examination of the combination of p53 and Ku70 may predict the radiosensitivity of rectal cancer before preoperative irradiation.

Appropriate polymorphonuclear neutrophil (PMN) recruitment is essential for host defense against infection. We investigated the significance of the preoperative PMN adhesion-migration process, as assessed by the flow chamber method, on postoperative infectious complications. Thirty-one consecutive patients with gastrointestinal malignancies, 21 colorectal and 10 gastric, who were undergoing elective surgery were enrolled. PMNs, isolated preoperatively from each patient's venous blood, were perfused onto a tumor necrosis factor a-stimulated human umbilical vein endothelial cell (HUVEC) monolayer through the flow chamber. We evaluated the adherent PMN number, the migrated PMN number, and the stuck PMN number by directly inspecting PMN interactions with a HUVEC monolayer under continuous shear flow simulating postcapillary venules. The expression of adhesion molecules on circulating PMNs was also measured. Patients were grouped into an infectious and a noninfectious group according to the occurrence of postoperative infectious complications defined by the Centers for Disease Control criteria. Eleven patients developed postoperative infectious complications. Although the number of preoperative in vitro adherent PMNs in patients with postoperative infection was significantly higher than in those without postoperative infection (P = 0.01), migrated PMN number was similar in both groups. Stuck PMN number tended to be higher in the infectious group than in the noninfectious group. The migrated PMN number showed a significant positive correlation with the adherent PMN number in the noninfectious group but not in the infectious group. Preoperative CD31 expression on circulating PMNs was significantly lower in the infectious group than in the noninfectious group. Preoperative in vitro derangement of the PMN adhesion-migration process is closely associated with postoperative infectious complications.

We report a case of autoimmune pancreatitis presenting as a mass in the head of the pancreas that was successfully diagnosed without pancreaticoduodenectomy. The patient was a 64-year-old man who had no complaint. A routine physical checkup unexpectedly revealed mild diabetes and a low-echoic mass in the pancreatic head. The diagnosis was made by noting irregular narrowing of the main pancreatic duct, hypergammaglobulinemia, and increased immunoglobulin G levels. An open wedge biopsy of the mass was performed; this showed a marked fibrosis with lymphocyte- or macrophage-predominant inflammatory infiltrates. Immunohistochemical study revealed that the remnant acinar cells expressed Fas (CD95) ligand and not Fas. We review some of the literature and discuss various features and diagnostic clues of autoimmune pancreatitis. Awareness of this pathologic condition may prevent confusion with pancreatic malignancy and unnecessary surgery.

Lysophosphatidic acid (LPA) is a lipid mediator with diverse effects on various cells. Here, we investigated the effects of LPA on human colon carcinoma DLD1 cells. Northern blot analysis revealed that DLD1 highly expressed LPA1/Edg-2 but showed only low expression of LPA2/Edg-4 and no expression of LPA3/Edg-7 at the mRNA level. Western blot analysis revealed that DLD1 cells highly expressed LPA1 at the protein level. Using the Boyden chamber assay, LPA markedly increased DLD1 cell migration at concentrations as low as 10 nm, with maximum stimulation at 100 nm (3.6-fold increase). Checkerboard analysis indicated that LPA stimulated both the chemotactic and chemokinetic migration of DLD1 cells. LPA induced a dose-dependent increase in the proliferation of DLD1 cells (3.2-fold increase at 20 mum). Furthermore, LPA stimulated DLD1 cell adhesion to collagen type I (2.0-fold increase at 10 mum) and also stimulated the secretion of both vascular endothelial growth factor (1.4-fold increase at 20 mum) and interleukin 8 (19-fold increase at 20 mum) by ELISA. In contrast, as for matrix metalloproteinase, LPA had no significant effect on pro-matrix metalloproteinase-2 secretion and its activation, as measured by Western blot analysis. Thus, LPA, at concentrations that are present physiologically, enhanced DLD1 cell migration, proliferation, adhesion, and secretion of angiogenic factors, all of which are crucial for cancer metastasis. In comparison, other human colon carcinoma cells (HT29 and WiDR) exclusively expressed LPA2. LPA enhanced their proliferation and secretion of angiogenic factors, whereas LPA did not enhance migration or adhesion. Our results suggest that LPA acts as a potent stimulator of colon cancer progression, although the binding to LPA1 and LPA2 induces slightly different responses.

Background In order to develop a safe and effective gene therapy for cancer, more powerful therapeutic genes must be selected and a gene transduction methodology needs to be devised that minimizes the total dose of vector required. We investigated the combination effect of 5-fluorouracil (5-FU), a first-choice drug for the treatment of colorectal cancer and adenovirus-mediated transfer of caspase-8 in DLD-1 colon cancer cells. Methods The degree of cell death was assessed by determining the percentage of cells which had died, and the degree of DNA fragmentation. The protein expression levels and degree of activation of caspase-8 were analyzed by Western blot analysis. The degree of transgene expression was assessed using adenoviral vectors expressing lacZ and GFP. Results Combination treatment led to a significant induction of apoptosis, whereas treatment with either approach alone resulted in only minimal cytotoxicity. Caspase-8 was only activated in cells that received the combined treatment. Exposure to 5-FU increased the quantity of transgene expression per cell, 48 h post-infection. A potentiating effect of adenoviral treatment was also seen when 5-FU treatment was substituted by the overexpression of cyclin-dependent kinase inhibitors, p21(WAF1/CIP1) and p27(KIP1), suggesting that the cytostatic effect of 5-FU augmented apoptosis induced by caspase-8 gene transduction by inhibiting the dilution of gene products associated with cell division. Conclusions This combination strategy may be very useful in the treatment of 5-FU-resistant colorectal cancers and may also be more generally helpful in minimizing the dose of therapeutic vectors used in cancer gene therapy. Copyright (C) 2002 John Wiley Sons, Ltd.

OBJECTIVE: Dietary restriction impairs polymorphonuclear neutrophil (PMN) recruitment into the local inflammatory site, resulting in susceptibility to infection. Probiotics enhance host immunity via conditioning host intestinal microflora. Oral administration of Bifidobacterium longum culture condensate (BCC) in a diet-restricted marine peritonitis model may enhance PMN recruitment into the inflammatory site. METHODS: Male ICR mice (n = 40) were assigned in equal numbers to control or BCC groups and subjected to 75% restricted food intake for 7 d. During dietary restriction, controls received only standard mouse chow, whereas the BCC group received standard mouse chow containing 1% BCC. Mice were killed before (0 h) or after (2 or 4 h) intraperitoneal glycogen injection. Peritoneal lavage fluid and exudative cells were recovered by, peritoneal lavage. Peritoneal exudative cell number was counted. Taper necrosis factor-alpha, interleukin-6, macrophage inflammatory protein-2, and interleukin-10 concentrations in peritoneal lavage-fluid were determined by enzyme-linked immuosorbent assay. CD11b, CD18; CD31, and CD62L expressions on circulating PMNs were measured by flow cytometry. RESULTS: Oral BCC administration unregulated PMN recruitment into the peritoneal cavity and increased peritoneal fluid cytokine concentrations as well as CD18 and CD62L expressions on circulating PMNs during glycogen-induced peritonitis. CONCLUSIONS: Oral BCC administration in a diet-restricted marine peritonitis model augmented P recruitment into the inflammatory site by upregulating cytokine concentrations in the local inflammatory site and adhesion molecule expression on circulating PMNs. Oral BCC administration may be a favorable modality for improving dietary restriction-induced host immunosuppression. (C)Elsevier Science Inc. 2003.

OBJECTIVE: Dietary restriction impairs polymorphonuclear neutrophil (PMN) recruitment into the local inflammatory site, resulting in susceptibility to infection. Probiotics enhance host immunity via conditioning host intestinal microflora. Oral administration of Bifidobacterium longum culture condensate (BCC) in a diet-restricted marine peritonitis model may enhance PMN recruitment into the inflammatory site. METHODS: Male ICR mice (n = 40) were assigned in equal numbers to control or BCC groups and subjected to 75% restricted food intake for 7 d. During dietary restriction, controls received only standard mouse chow, whereas the BCC group received standard mouse chow containing 1% BCC. Mice were killed before (0 h) or after (2 or 4 h) intraperitoneal glycogen injection. Peritoneal lavage fluid and exudative cells were recovered by, peritoneal lavage. Peritoneal exudative cell number was counted. Taper necrosis factor-alpha, interleukin-6, macrophage inflammatory protein-2, and interleukin-10 concentrations in peritoneal lavage-fluid were determined by enzyme-linked immuosorbent assay. CD11b, CD18; CD31, and CD62L expressions on circulating PMNs were measured by flow cytometry. RESULTS: Oral BCC administration unregulated PMN recruitment into the peritoneal cavity and increased peritoneal fluid cytokine concentrations as well as CD18 and CD62L expressions on circulating PMNs during glycogen-induced peritonitis. CONCLUSIONS: Oral BCC administration in a diet-restricted marine peritonitis model augmented P recruitment into the inflammatory site by upregulating cytokine concentrations in the local inflammatory site and adhesion molecule expression on circulating PMNs. Oral BCC administration may be a favorable modality for improving dietary restriction-induced host immunosuppression. (C)Elsevier Science Inc. 2003.

Background. Platelet-derived endothelial cell growth factor (PD-ECGF) is reported to be highly expressed in tumors and inflammatory tissues, but its expression and role in inflammatory bowel disease (IBD) are still unclear. In this study we examined the location and tissue density of cells immunoreactive for PD-ECGF in the colonic mucosa of (IBD). Methods. Paraffin-embedded sections of colonic tissue from patients with ulcerative colitis (UC) or Crohn's disease (CD) were immunostained for PD-ECGF. As controls, noninflamed mucosa of IBD, as well as normal colonic mucosa from patients with colorectal cancer, were used. Also, cancer tissues were evaluated. In addition, changes in the expression of PD-ECGF in human umbilical vein endothelial cells (HUVEC) after treatment with inflammatory cytokines and angiogenic factors, as well as after coculture with colon cancer cell lines, were evaluated by flow cytometry. Results. In normal colonic mucosa and noninflamed mucosa of (IBD), PD-ECGF expression was negligible. In inflamed colonic mucosa, strong expression was observed, predominantly in macrophages and fibroblasts. Vascular endothelial cells of the inflamed colonic mucosa, but not of normal colonic mucosa or of neoplastic tissues, stained for PD-ECGF, and the microvessel density was significantly increased in the severely inflamed mucosa. Flow cytometry demonstrated that PD-ECGF was constitutively expressed in HUVEC. Inflammatory cytokines and vascular endothelial growth factor (VEGF) increased its expression, whereas basic fibroblast growth factor (bFGF) decreased it. Coculture with colon cancer cell lines in direct contact, but not in those without contact, also resulted in an important decrease in the expression of PD-ECGF in HUVEC. Conclusions. Autocrine production of PD-ECGF by endothelial cells may be a mechanism of inflammatory angiogenesis, but not tumor angiogenesis, and may be particularly important for the maintenance of damaged vasculature in IBD.

Background: The stromal cell-derived factor-1/CXC chemokine receptor-4 (SDF-1/CXCR4) signal has been shown to be important in various immunological reactions. Recent studies have suggested that CXCR4 is expressed in certain cancer cells and that they use this chemokine receptor efficiently for metastasis formation. Method: The expression of CXCR4 was evaluated by immunohistochemical study in 79 surgically resected invasive ductal carcinomas, and the relation between the staining pattern and clinicopathological features was examined. Results: CXCR4 was diffusely and homogeneously expressed in 59 cancers, which were further divided into 28 high-expression and 31 low-expression cancers by their staining intensity. The other 20 cancers showed heterogeneous immunoreactivity in tumor tissue, which was defined as focal type. In comparison with the diffuse type, focal type tumors showed significantly more extensive lymph node metastasis, because the number and extent of metastatic nodes were larger in the focal than the diffuse type. In the diffuse type, the rate of node-positive cases did not show a difference in staining intensity. However, high-CXCR4 tumors showed more extensive nodal metastasis in comparison with low-expression tumors. In contrast, the expression pattern of CXCR4 did not have a significant correlation with hematogeneous metastasis. The overall survival of these patients tended to be better in the diffuse type than in the focal type, although the difference was not statistically significant. Conclusion: The expression pattern of CXCR4 was significantly correlated with the degree of lymph node metastasis in breast cancers. Our data suggest that CXCR4 might be particularly important in facilitating metastasis through the lymphatic system.

Background: Vascular endothelial growth factor C (VEGF-C) and D (VEGF-D) are considered to be potentially lymphangiogenic and can selectively induce hyperplasia of the lymphatic vasculature. In this study, we aimed to clarify the relation between expression of VEGF-C and -D and lymphatic metastasis in early gastric cancers. Methods: Using the specific antibodies, we classified 105 cases which were treated as gastrectomy with standard lymphadenectomy at the First Department of Surgery, Tokyo University Hospital, between 1994 and 2001, into three groups (diffuse type, focal type and negative type) for VEGF-C and two groups (positive and negative) for VEGF-D. Results: There was a significant correlation between the expression of VEGF-C and -D and lymphatic invasion but not with venous invasion. All of the 22 cases that were negative for VEGF-C and -D were histologically classified as adenocarcinoma of undifferentiated type and showed negative lymph node metastasis and also negative lymphatic invasion. VEGF-C was positive in all tumors of differentiated type, while its expression varied in tumors of undifferentiated type. The VEGF-D positive rate is much lower than that of VEGF-C. In undifferentiated tumors in particular, VEGF-D was positive only in 4/64 (6%) and three of these four had nodal metastasis. Therefore, in tumors of differentiated type, expression of VEGF-C and -D had no clinical relevance. In tumors of undifferentiated type, the negative expression of VEGF-C suggests lack of nodal metastasis, while the positive expression of VEGF-D suggests nodal metastasis. The lymph node metastasis was significantly related to the expression of VEGF-C and -D in adenocarcinomas of undifferentiated type but not in those of differentiated tumors. Conclusions: In early gastric cancers of histologically undifferentiated type with negative expression of VEGF-C and -D, limited surgery might be safely applied because the possibility of nodal metastasis is very low. These observations are based only on retrospective analysis of a small case series and further evaluation with a larger number of cases is necessary.

Peritoneal dissemination is the most frequent type of recurrence in patients with gastric cancer with serosal exposure, irrespective of whether they have undergone curative gastrectomy. The purpose of this study was to establish a method to detect micrometastatic cells in the abdominal cavity and predict peritoneal recurrence in patients with such gastric carcinomas. A total of 86 patients with gastric carcinoma, undergoing gastrectomy, were examined. Reverse transcriptase-polymerase chain reaction (RT-PCR) assay was used to detect carcinoembryonic antigen (CEA) mRNA in abdominal lavage fluid. Twenty-four cases without serosal exposure were negative, while all 13 cases with macroscopic peritoneal dissemination were positive for CEA mRNA. Among the 49 cases with macroscopic serosal invasion and without peritoneal metastasis, cancer cells were detected in 27 cases with RT-PCR while in only 6 cases with conventional cytology. All cytologically-positive cases were also positive for CEA mRNA. Among the 27 CEA-positive cases, 15 patients (56%) relapsed with peritoneal metastasis within 12 months after gastrectomy. In contrast, none of the 22 CEA-negative cases had peritoneal recurrence within 16-60 months of observation, whereas in 43 cytologically-negative cases, 10 patients relapsed with peritoneal recurrence. As compared with conventional cytological examination, this method would be clinically more beneficial for detecting free cancer cells in the peritoneal cavity and for predicting peritoneal recurrence in gastric carcinoma with serosal invasion.

BACKGROUND. Preoperative radiotherapy reduces the rate of local recurrence and improves the chance of survival in patients with resectable, advanced rectal carcinoma. However, because not all tumors respond similarly to radiation, sorting out suitable patients is required to irradiate tumors rationally. The authors examined the possible role of Ku protein in determining tumor radiosensitivity and disease free survival in patients with rectal carcinoma. METHODS. The authors studied 96 patients with advanced rectal carcinoma. In preradiation biopsy specimens of tumor samples, the number of cells that were stained positive for Ku protein was evaluated by immunohistochemistry. The expression pattern of Ku protein was examined for an association between tumor radiosensitivity (which was determined according to T classification downstaging, complete pathologic response, or Response Evaluation Criteria in Solid Tumors) and disease free survival. RESULTS. There was a high degree of correlation between the percentage of cells that expressed the 70-kDa Ku protein (Ku70) and the 86-kDa Ku protein (Ku86) in the tumor sections (correlation coefficient = 0.85; P < 0.001). The expression pattern of Ku protein was correlated not only with tumor radiosensitivity but also with disease free survival. Pathologic TMN classification, histopathologic grade, and Ku70 expression were significant prognostic variables for disease free survival in a multivariate analysis (P = 0.0031, P = 0.030, and P = 0.023, respectively). CONCLUSIONS. Ku70 and Ku86 raise the predictive possibility of tumor radiosensitivity. Ku may be a useful parameter for selecting patients with rectal carcinoma for preoperative radiotherapy. (C) 2002 American Cancer Society.

Cancer cell adhesion to lymphatic endothelial cells (LEC) was examined under shear stress mimicking lymph flow. An established rat gastric adenocarcinoma cell line, BV9, was perfused over a primary cultured monolayer of LEC, which were explanted from the rat thoracic duct, and the adhesion pattern was observed. BV9 preferably adhered to LEC, at a level 8-fold greater than that to vascular endothelium in the unstimulated condition. When shear stress was increased after adhesion, a considerable number of BV9 on LEC withstood shear up to 50 dyn/cm(2), while BV9 attached on vascular endothelium did not remain adherent under 5 dyn/cm2. Adhesion was significantly augmented by prestimulation of LEC with 10 ng/ml IL1-beta or 500 ng/ml TNF-alpha. Our study indicates high affinity between cancer cells and LEC, and suggests the possibility that lymph node metastasis arises from cancer cells adherent to LEC, which can be augmented by an inflammatory stimulus.

The function of dendritic cells (DCs). antigen-presenting cells that can initiate and regulate cellular and humoral responses, is highly influenced by their level of maturation. Immature DCs may be harmful in anti-tumor immunotherapy, because they can induce immunotolerance rather than immunostimulation. In this study, the authors sought to determine the optimal culture conditions for obtaining fully mature DCs. When DCs were cultured in agonistic anti-CD40 monoclonal antibody-immobilized plates, they showed a higher expression of the maturation marker CD83 than DCs cultured without CD40 ligation or those cultured in medium supplemented with anti-CD40 monoclonal antibody. In addition, when interferon-gamma (IFN-gamma) was added to the medium, additive up-regulation of CD83 expression was observed. These DCs treated with both maturation signals showed a higher secretion of interleukin-12. To evaluate the capacity of antigen presentation. specific cytotoxic T lymphocytes were generated using autologous DC pulsed with a human lymphocyte antigen-A24-restricted peptide epitope derived from carcinoembryonic antigen. Interferon-gamma-secreting CD8+ T cells were analyzed by now cytometry using the cellular affinity matrix technology. Dendritic cells, matured with CD40 ligation and IFN-gamma, were more efficient at eliciting an antigen-specific T-cell response in vitro than DCs stimulated with anti-CD40 monoclonal antibody or IFN-gamma alone. A cytotoxicity assay using carcinoembryonic antigen-expressing tumor cell lines also showed that DCs matured with both signals were more efficient at inducing cytotoxic T lymphocytes. These results demonstrate that DC culture in an anti-CD40 monoclonal antibody-immobilized plate in medium supplemented with IFN-gamma has a positive impact oil DC maturation and may be optimal for eliciting an antigen-specific T-cell response without the need for CD4+ T-helper epitopes.

Caspase-8 is a member of the cysteine protease family that plays a critical role in death receptor-mediated apoptosis. We previously demonstrated that adenovirally transduced caspase-8 efficiently induced apoptosis in tumor cells (Shinoura et al. (2000) Hun. Gene Ther. 11, 1123-1137). However, to ensure safety in clinical applications some devise for minimization of the dose of adenoviral vector required for sufficient antitumor effect is needed. In this study, we evaluated the proapoptotic effect in DLD-1 colon cancer cells of a combination of low-dose infection with an adenoviral vector expressing caspase-8 and X-ray irradiation. Under these conditions, X-ray irradiation strongly induced apoptosis whereas irradiation without transduction only had a trace proapoptotic effect. Overexpression of bcl-xL strongly blocked the activation of caspase-8 and induction of apoptosis, suggesting that adenovirally transduced caspase-8 was activated at a point downstream of mitochondria. This combination strategy may be a useful modality for gene therapy of colorectal cancer. (C) 2002 Elsevier Science (USA).

Purpose. Local resection of the stomach for early gastric cancer is being performed more frequently, despite which no report focusing on the Postoperative complications has been published. The purpose of this study was to investigate the incidence and factors affecting postoperative complications after local resection of the stomach. Methods. Local resection of the stomach was performed in 37 patients with gastric cancers, submucosal tumors (SMT), or bleeding gastric ulcers, 24 of whom underwent gastroscopy at least once after their operation. We retrospectively examined the complications and background relating to the operations performed in those 24 patients. Results. Postoperative hemorrhage occurred in 2 patients, an open ulcer developed on the suture line in 2 and leakage developed in 1. The hemorrhage and open ulcer were observed only when wide resection with regional lymph node dissection was performed for early gastric cancers in the middle third of the stomach. Conclusion. These findings show that the possibility of postoperative hemorrhage and open ulcers on the suture line should be borne in mind, especially when wide local resection with lymph node dissection is performed for cancers in the middle part of the stomach.

Purpose. In the present study, we investigated the effect of troglitazone, a selective ligand and agonist of PPAR-gamma on the metastatic potential of human colon cancer cells. Methods. High- and low-PPAR-gamma expression clones of the colon cancer cell line, HT29, namely clones 21 and 3 respectively, were used. We investigated the effect of troglitazone on the proliferation, on the adhesion to extracellular matrix proteins and on the synthesis of matrix metalloproteinases (MMPs) of colon cancer cells. Results. Troglitazone inhibited the proliferation of both subclones, in a dose-dependent manner, and the inhibitory effect correlated with the level of PPAR-gamma expression. Troglitazone strongly inhibited the production of MMP-7, an enzyme associated with invasiveness of cancer cells, by both subclones. In addition, troglitazone caused a strong decrease in the adhesion of clone 21 to extracellular matrix (ECM) proteins, laminin and type IV collagen. This effect was independent of beta1-integrins expression. Conclusion. In addition to inhibition of cancer cell growth, troglitazone had an inhibitory effect on two important events associated with the metastatic potential of cancer cells, production of MMPs and adhesion to ECM proteins. Consequently, troglitazone is a promising agent for the treatment and prevention of colon cancer metastasis.

Cholesterol granuloma of the breast is a rare benign condition which is often clinically and radiologically indistinguishable from breast carcinoma. We herein report the case of a 62-year-old asymptomatic woman who was found on a routine breast examination to have an elastic hard mass, measuring 0.9 cm in diameter, in the upper outer quadrant of the left breast. Physical examination and ultrasonography strongly suggested a carcinomatous lesion. A cytological examination of a fine-needle aspiration biopsy specimen was inconclusive because of the paucity of epithelial cells. A histological examination of excisional biopsy materials showed scattered cholesterol crystals arranged in irregular, parallel arrays, surrounded by histiocytes and giant cells, which were consistent with a diagnosis of cholesterol granuloma. This case report indicates the importance of performing a histological examination to establish the final diagnosis of cholesterol granuloma. We believe that a better awareness of this breast disease might help to prevent both a misdiagnosis and unnecessary surgery.

Dendritic cells (DCs) are essential antigen-presenting cells with a wide variety of functions relating to both adaptive and innate immunity. Recently, interactions of DCs with natural killer (NK) cells and NK1.1-positive T cells have been reported in mice. However, in humans, this interaction is not well understood. Here we report the use of a coculture method to analyze the modulation of NK cell function in antitumor immunity by DCs. We found that peripheral blood DCs (PDCs) enhanced NK cell activity in cytotoxicity assay, even without direct contact between DC and NK cells. In contrast, neither monocyte-derived DCs (MoDCs), nor TNF-alpha-treated MoDCs, stimulated NK lytic activity. Secretion of IL-12 and TNF-alpha into the PDC-NK coculture supernatant was increased. However, blocking antibodies against these cytokines could not completely abolish the upregulation of NK activity, suggesting the presence of other soluble factor(s) that affect DC-NK cell interaction. To summarize, this study demonstrates for the first time the direct activation of human NK cells by DC-NK cell interaction in vitro, suggesting that DCs may have a central role linking the innate and adaptive immune responses. Moreover, in stimulating NK cell function, PDCs appear to have a different potential from MoDCs. (C) 2001 Elsevier Science.

It remains a question whether hematogeneous metastasis arises from a single cancer cell attached to the local endothelium or from a cluster of cancer cells trapped in the vascular bed in the target organ. Adhesive interaction of the single cell form and the clustered form of cancer cells was examined under flow conditions, using two subclones of mouse colon adenocarcinoma Colon 26. A subclone NL17, but not NL14, formed many clusters composed of tumor cells and platelets just after the addition of platelet rich plasma (PRP). Under the shear of 1.0 dyn/cm(3), the clustered form of NL17 tethered on laminin or mouse endothelial cell line in hepatic sinusoids (HSE) more frequently than the single cell form of NL17 and NL14. However, all of the clusters showed only transient attachment and never underwent stable arrest on coated laminin, while the single cell form of NL14 and NL17 underwent immediate arrest under shear conditions. On HSE stimulated with TNF-alpha, a small number of NL17 clusters made stable adhesion, although all the clusters detached if the shear stress was increased above 4.0 dyn/cm(2). In contrast, the single form of arrested NL17 as well as NL14 remained adherent even at shear of 8.0 dyn/cm(2). Compared with single cell, binding of cancer cell clusters to laminin and HSE showed lower resistance to shear stress, although they had adhesive interactions more frequently inflow condition. Since NL17 cells form significantly more metastases by intravenous injection in vivo, our data suggest that "stable adhesion" observed in our flow assay system is not always a prerequisite for clustered cancer cells to develop into metastatic lesions.

Background/Aims: Glutamine synthetase (GS) catalyzes the synthesis of glutamine, a major energy source of cells, and is upregulated in a subset of human hepatocellular carcinomas (HCCs), GS expression may be related to tumor recurrence, since GS-expressing tumors have a growth advantage in that they are independent of the extracellular glutamine supply, However, there are no studies concerning the prognostic value of GS expression in patients with HCC. Methods: Seventy-three patients with a single advanced HCC nodule who underwent curative hepatectomy were included in the study. GS expression in the HCC nodules was analyzed immunohistochemically and was compared with clinicopathologic features and the behavior of the tumors. Survival curves were assessed according to the Kaplan-Meier product-limit method and multivariate analysis based on the Cox regression model was performed. Results: GS expression was strong in 26 cases (35.6%, high-GS group) and weak or absent in 47 cases (64.4%, low-GS group), Univariate analysis showed that the high-GS group had a significantly shorter disease-free survival time than the low-GS group (p=0.042). Multivariate analysis revealed that GS expression (p=0.021), as well as Child's classification (p=0.005) and portal invasion (p=0.039), was a significant and independent prognostic parameter that affected tumor recurrence. Conclusion: The results of this study indicate that GS expression may enhance the metastatic potential in HCC, and GS immunostaining may be helpful in identifying HCC patients at high risk for disease recurrence.

Epidemiological studies have demonstrated that nonsteroidal anti-inflammatory drugs (NSAIDs), known to inhibit cyclooxygenase (COX), reduce the risk of colorectal cancer. COX is a key enzyme in prostaglandin biosynthesis, and two isoforms of COX, COX-1 and COX-2, have been identified. Recently COX-2 has been reported to frequently overexpress in colorectal neoplasms and to play a role in colorectal tumorigenesis and tumour progression. In this study, using immunohistochemistry, we examined COX-2 expression in advanced human colorectal cancer and its correlation with clinicopathological features. COX-2 expression was observed mainly in the cytoplasm of cancer cells in all the specimens examined, but some stromal cells and endothetial cells were also stained. According to the grade of COX-2 expression of the cancer cells, patients were divided into high- and low-COX-2 expression groups. High-COX-2 expression significantly correlated with tumour recurrence, especially haematogenous metastasis. These results suggest that a selective COX-2 inhibitor can be a novel class of therapeutic agents not only for tumorigenesis but also for haematogenous metastasis of cololectal cancer. To our knowledge, this is the first report on the correlation between COX-2 overexpression and recurrence of colorectal cancer. (C) 2000 Cancer Research Campaign.

alpha-Glycosylceramides, such as alpha-galactosylceramide and alpha-glucosylceramide, induce antitumor immunity in various murine cancer models. In the murine hepatic metastasis model, V alpha 14 TCR(+)NK1.1(+) T cells, which accumulate preferentially in the liver, are considered to play a key role in the induction of antitumor immunity by alpha-glycosylceramides. We recently reported that V alpha 24 TCR+ NKT cells, the human homologues of murine V alpha 14 TCR(+)NK1.1(+)cells, are rarely seen among freshly isolated human hepatic lymphocytes, Therefore, it is important to examine whether alpha-glycosylceramides also enhance the antitumor cytotoxicity of human hepatic lymphocytes, as they have been shown to do in murine systems, to determine the usefulness of alpha-glycosylceramides in cancer immunotherapy in humans. Here, we show that alpha-glycosylceramides greatly enhance the cytotoxicity of human hepatic lymphocytes obtained from cancer patients against the tumor cell lines, K562 and Colo201, in vitro, The direct effector cells of the elicited cytotoxicity were CD3(-)CD56(+) NK cells. Even though V alpha 24 TCR+NKT cells proliferated remarkably in response to alpha-glycosylceramides, they did not contribute directly to the cytotoxicity. Our observations strongly suggest the potential usefulness of alpha-glycosylceramides for immunotherapy of liver cancer in humans based on their ability to activate CD3-CD56+ NK cells in the liver.

Polymorphonuclear cell (PMN) transmigration across the TNF-alpha-stimulated endothelial cell (HUVEC) monolayer in the presence of shear flow was monitored with time-lapse videotapes. More than half of the PMN that arrested on HUVEC transmigrated through endothelial cell junctions within the following 15 min. The kinetics of transmigration was significantly faster than that of PMN placed under static conditions. Once PMN crept into the subendothelial space, they showed random migration beneath the HUVEC monolayer. PMN that did not transmigrate moved on the apical surface of HUVEC in the direction of flow down stream. Anti-beta 1 integrin mAb (4B4) and RGD peptide inhibited the transmigration more effectively than anti-beta 2 integrin mAb (TS1/18) and almost totally abrogated transmigration. When HUVEC were cultured on fibronectin or laminin, the transmigration was significantly inhibited by anti-alpha 5 or alpha 6 integrin mAbs, respectively. Our data clearly indicate that shear stress affects the migration behavior of PMN arrested on endothelium and suggest that binding to subendothelial extracellular matrix via beta 1 integrins is another essential step in leukocyte extravasation. (C) 2000 Academic Press.

Background: Analysis of serum cytokine levels has shown that cancer-bearing hosts have lower levels of IL-2 and IFN-gamma, suggesting that Th1-type immunity is impaired by cancer. However, the mechanisms of the Th1 dysfunction are not clearly understood. Method: The frequencies of Th1 cells in CD4(+) helper T cells were evaluated with an intracytoplasmic cytokine staining method in peripheral blood lymphocytes (PBL) and lymph node lymphocytes (LNL) of patients with gastrointestinal cancer. Results: Activation of lymphocytes with PMA + lonomycin induced the expression of IL-2 and IFN-gamma in each lymphocyte population. Compared with PBL of non-malignant donors, PBL in cancer patients contained significantly lower frequencies of CD4(+) T cells that produced IL-2 and IFN-gamma. LNL in cancer patients also contained lower levels of IL-2- and IFN-gamma-producing CD4(+) T cells, although the percentages did not show significant differences from those of PBL in the same patients. Conclusion: Our data suggest that suppression of Th1 cytokine in cancer patients is,at least in part, due to the decreased frequency of Th1 cells with CD4(+) phenotype.

Background: Thymidylate synthase (TS) is regarded as a parameter of 5-fluorouracil (5-FU) chemosensitivity for colorectal carcinoma. Recent researchers indicate that the chemosensitivity of 5-FU for colorectal carcinoma with low expression of TS is better than tumors with high expression of TS. But the relation between TS expression and overall survival of curatively resected colorectal cancer patients has been less studied. Methods: Specimens of curatively resected colon carcinoma from 148 patients were included in this study. TS expression in the tumor was assessed by immunohistochemical staining technique, and the patients were categorized into TS-(+) and TS-(-) groups. First, the relation between TS expression and survival of patients was examined. Next, for each group, we compared survival between the chemotherapy-(+) and the chemotherapy-(-) subgroup. Results: Overall survival was significantly better in the TS-(-) group (n = 107) than in the TS-(+) group (n = 41) (P = .0003). In the TS-(-) group, there was Little difference between the chemotherapy-(+) and the chemotherapy-(-) subgroup. In the TS-(+) group, the survival of the chemotherapy-(+) subgroup was significantly better than the chemotherapy-(-) subgroup (P = .0439). Conclusions: TS, itself, may be a prognostic factor for colon carcinoma; and 5-FU adjuvant chemotherapy may be appropriate for colon carcinoma with high expression of TS.

Background: Dihydropyrimidine dehydrogenase (DPD) is the first enzyme that metabolizes 5-fluorouracil (5-FU). Until now, enzymatic activity or mRNA expression of DPD has been investigated. However, there are no papers on immunohistochemical evaluation of DPD. We investigated DPD staining on immunohistochemistry, and examined the relationship among immunohistochemical score, protein level and mRNA expression of DPD. Materials and methods: Forty-seven resected colon cancer specimens, four colon cancer cell lines, two xenografts by colon cancer cell lines, and human mononuclear cells were used. Immunohistochemistry was performed using DPD monoclonal antibody. Protein levels were determined by Western blot analysis. And mRNA levels were calculated by semi-quantitative reverse transcription polymerase chain reaction (RT-PCR). Results: DPD was strongly expressed in the cytoplasm of cancer cells, and in the cytoplasm of macrophage and plasma cells. The immunohistochemical score was more correlated with protein levels (P = 0.0054) than mRNA expression (P = 0.9028). Conclusions: We investigated the characterization of DPD immunohistochemically, and showed that immunohistochemical expression of DPD can be used to predict the sensitivity of colorectal carcinomas to 5-FU.

The expression of thymidine phosphorylase (TP) in carcinoma of the papilla of Vater was studied to clarify its significance in tumor progression and in determining prognosis. Fifty-nine cases of surgically resected carcinoma of the papilla of Vater were studied. Immunohistochemical staining was performed to evaluate the expression of TP, microvessel count and p53 overexpression. TP expression was demonstrated in tumor cells in 62.7% (37/59) of the cases. A higher frequency of regional lymph node metastasis was found in TP-positive tumors than in TP-negative tumors (P=0.006). TP-positive tumors were more advanced than TP-negative tumors with regard to clinical stage (P=0.035). TP-positive tumors had significantly higher microvessel density (27.6+/-10.1) than TP-negative tumors (20.4+/-10.0, P=0.01). Moreover, TP expression was significantly correlated with a poor prognosis (P=0.02). These suggest that in carcinoma of the papilla of Vater, TP production by tumor cells is correlated with tumor progression through its regulatory effect on neovascularization.

Polymorphonuclear leukocytes (PMN) were perfused over extracellular matrix protein substrates under laminar shear flow. Under shear below 1.5 dyn/cm(2), many PMN tethered to immobilized laminin but not to fibronectin or vitronectin, Almost all the tethered PMN immediately arrested on laminin. The number of tethered PMN was mostly abrogated by mAbs to integrin alpha 6 Or beta 1 chains at concentrations of more than 5 mu g/ml. Addition of the two mAbs together produced no further inhibition compared with each mAb alone. In contrast, none of the mAbs to alpha 2, alpha 3, and beta 4 chains showed significant inhibition, indicating that PMN tethering to laminin is mostly dependent on alpha 6 beta 1 integrin. The addition of 10-100 ng/ml IL-8 in the assay medium before perfusion partially reduced PMN tethering to laminin. Stimulation with IL-8 also induced detachment of some tethered PMN within 30 s. Thus, IL-8 partially weakens the adhesiveness of alpha 6 beta 1 integrin on PMN in how conditions. (C) 2000 Academic Press.

Background. Degradation of basement membrane and extracellular matrix by matrix metalloproteinases (MMPs) is believed to be an essential step in the complicated process of hematogenous metastasis. MMP-1 is a member of collagenases, a family of MMPs that degrades collagens type I, II, and III, main components of the interstitial stroma. The purpose of this study was to investigate the expression of MMP-1 in colorectal cancer and its correlation with hematogenous metastasis. Patients and Methods. We examined 133 cases of colorectal cancer (Dukes A: 72 Dukes B: 26 Dukes C: 23 Dukes D: 12). Sections were cut from formalin-fixed, paraffin-embedded samples containing the deepest site of cancer invasion and stained immunohistochemically with a monoclonal antibody to MMP-1. According to the area of the tumor that was stained, patients were divided into high- and low-MMP-1 expression groups. Results. MMP-1 expression was observed in the cytoplasm of cancer cells, some stromal cells, and a few normal epithelial cells of colonic mucosa. High MMP- 1 expression was found in 47 (35.3%) cases and low in 86 (64.7%). Hematogenous metastasis was identified in 14 (29.8%) of high-MMP-1 groups and 12 (13.9%) of low-MMP-1 groups. MMP-1 expression significantly correlated with hematogenous metastasis of colorectal cancer, but no correlation was found between MMP-1 expression and the other clinicopathological features investigated. Conclusions. MMP-1 expression may be a novel marker for hematogenous metastasis of colorectal cancer, and its inhibition may be a strategy for prevention of metastasis.

BACKGROUND. Platelet-derived endothelial cell growth factor (PD-ECGF) is an angiogenic factor that has potent chemotactic activity for endothelial cells. Although it is expressed in the majority of colorectal tumors, and some reports suggest that its high expression is related to poor prognosis, to the authors' knowledge there is yet no consensus regarding whether PD-ECGF expression is a prognostic factor. To investigate the prognostic value of PD-ECGF and its role in tumor angiogenesis, an immunohistochemical study of PD-ECGF expression and tumor vasculature was performed and their relation with the clinicopathologic factors in patients with advanced colorectal carcinoma was evaluated. METHODS. Formalin fixed, paraffin embedded specimens from 86 colorectal carcinoma patients (40 cases in the muscularis propria and 46 cases in the subserosa) were immunostained for PD-ECGF and CD31 as a marker for vascular endothelial cells and expression of PD-ECGF was evaluated using an image analysis system. Patients were divided into high expression and low expression groups based on PD-ECGF expression, and were divided into high vascular grade and low vascular grade groups based on the microvessel density. Correlations between PD-ECGF expression and vascular grade and between PD-ECGF: expression,vascular grade, and the clinicopathologic features of the patients were evaluated statistically. RESULTS. PD-ECGF expression was observed predominantly in the turner stroma and not in tumor cells. The cells that stained strongly for PD-ECGF were confirmed to be macrophages infiltrating the interstitial tissue of the tumor. High PD-ECGF expression was found in 56 cases (65.1%) and low expression was detected in 30 cases (34.9%). Thirty-one of 86 tumors (36.0%) showed high vascular grade and 55 (64.0%) showed lo iv vascular grade. No correlation between PD-ECGF expression and vascular grade was found, but there was an inverse correlation between PD-ECGF expression and the rate of incidence of lymph node and hematogenous metastasis. These correlations were statistically significant. Vascular grade was not found to correlate with the clinicopathologic features, CONCLUSIONS. Patients with high PD-ECGF expression had a lower rate of incidence of lymphatic and hematogenous metastasis, with a consequently better prognosis than patients with low PD-ECGF expression. PD-ECGF expression did not correlate with vascular grade, suggesting that PD-ECGF plays little role in tumor angiogenesis of colorectal carcinoma. Based on these data, the authors conclude that macrophages infiltrating the tumor stroma produce PD-ECGF and play important roles in the immune reaction against the tumor rather than in tumor angiogenesis. Cancer 2000;88:42-9, (C) 2000 American Cancer Society.

The aim of this study was to determine whether colon cancer cells flowing in blood exhibit the same adhesion pattern to the vascular bed as leucocytes using a flow adhesion system. In shear flow conditions, five colon cancer cell lines showed less tethering to E-selectin substrates than polymorphonuclear cells (PMN). However, some of the Colo201 cells formed complete arrest on E-selectin in continuous shear flow which was never observed in PMN cells. Colo201 cells expressed both sialyl Le-x and sialyl Le-a at similar levels in flow cytometry. However, the staining pattern showed marked contrast under the fluorescein microscope. The cell membrane of Colo201 cells was uniformly stained with anti-salyl Le-a MAb, whereas anti-sialyl Le-x MAb only stained in the patchy areas. Pretreatment of Colo201 cells with anti-ale-a decreased tethering, while anti-sle-x significantly inhibited the arrest formation. Our data suggest that E-selectin alone can mediate colon cancer cell lodgement and subsequent metastasis without the contribution of integrin molecules and that the different distribution of E-selectin ligands may affect the adhesion behaviour of colon cancer cells in flow conditions. (C) 2000 Elsevier Science Ltd. All rights reserved.

Under the physiological shear condition, cultured colon cancer cells bound to laminin (LM), but not to fibronectin or vitronectin. Most of the tethered cells did not roll, but arrested immediately and spread within 10-30 min on LM under the continuous presence of shear flow. The tethering of Colo201 was partially inhibited by monoclonal antibodies (mAbs) to alpha 6 integrin and a combination of mAbs to beta 1 and beta 4 integrins, but not by mAb to 67KD laminin receptor. Some Colo201 cells still tethered at 4 degrees C. This suggests that alpha 6 beta 1 and alpha 6 beta 4 integrins participate in Colo201 tethering on LM, although other non-integrin molecules play roles. In contrast, the spread of Colo201 was effectively inhibited by the mAbs to integrin alpha 2, alpha 6 and beta 1 chains. The effect of anti-alpha 2 plus anti-alpha 6 mAbs was almost equal to anti-beta 1, suggesting that Colo201 cells mainly use alpha 2 beta 1 and alpha 6 beta 1 integrins for spreading on LM. When the cells were perfused on subconfluent endothelial cells (HUVEC) cultured on LM, they did not tether on HUVEC but did on coated LM exposed at intercellular gap area. Immunohistochemistry revealed that LM abundantly existed in the cytosol of human portal and hepatic vein endothelial cells. These data suggest that LM can mediate from tethering to spreading of colon cancer cells under the blood flow and plays an essential role in haematogeneous metastasis.