北山 丈二

AIM: The clinical efficacy of chemoradiotherapy (CRT) is largely dependent on host immune status. The aim of this study was to identify possible markers expressed on circulating mononuclear cells to predict tumour response in patients with locally advanced rectal cancer (LARC). METHODS: Peripheral blood samples were obtained from 47 patients diagnosed with LARC before and after CRT. The numbers of lymphocytes and monocyte subsets were analysed using flow cytometry. Based on clinical and pathological findings, patients were classified as high or low responders. RESULTS: Lymphocyte counts were markedly decreased after CRT. Total numbers of lymphocytes (p = 0.030) and CD4(+) T cells (p = 0.041) in post-CRT samples were significantly lower in low responders than in high responders. In contrast, monocyte counts were not reduced and the number of CD14dim (+) CD16(+) nonclassical (patrolling) monocytes were somewhat increased after CRT (p = 0.050). Moreover, the ratios of programmed cell death ligand 1 (PD-L1) (+) cells on patrolling monocytes before and after CRT were significantly higher in low responders than in high responders (p = 0.0046, p = 0.0006). The same trend was observed for classical and intermediate monocytes. The expression of PD-L1 on patrolling monocytes before CRT correlated inversely with the number of T cells and natural killer (NK) cells after CRT. PD-L1(+) ratio in patrolling monocytes was an independent predictor for response to CRT. CONCLUSION: Programmed cell death ligand 1 (PD-L1) expression on patrolling monocytes suppresses cell-mediated immunity in patients receiving CRT which could be related to tumour response, and may be a useful biomarker for decision-making in the management of patients with LARC.

Mouse studies have reported anti-stress effects of Lactiplantibacillus plantarum SNK12 (SNK). Specifically, oral SNK administration increased mRNA levels of hippocampal neurotrophic factor and gamma-aminobutyric acid receptor in mice with sub-chronic mild stress-induced social defeat; moreover, it improved depressive behavior. We aimed to evaluate the efficacy of SNK ingestion against stress in healthy adults. We used the Uchida–Kraepelin test for the stress load, with a low-dose (50 mg/day), high-dose (150 mg/day), and placebo groups (dextrin). The primary outcome was the psychological evaluation as measured by the Profile of Mood States 2nd Edition (POMS2) using total mood disturbance (TMD) scores. The secondary outcomes were the score of each POMS2 item, salivary cortisol as a stress marker, and autonomic balance with the low frequency (LF)/ high frequency (HF) ratio. Compared with the placebo group, the SNK ingestion group showed significantly lower TMD scores. Additionally, compared with the placebo group, the high-dose group showed significantly lower scores for Tension-Anxiety and Confusion-Bewilderment, while the low-dose group showed significantly lower Anger-Hostility scores, salivary cortisol levels, and LF/HF scores. Our findings suggest that SNK ingestion could relieve stress (negative feelings, anxiety, tension, embarrassment, confusion, anger, and hostility) resulting from the temporary load caused by work and study.

PURPOSE: Although neutrophil extracellular traps (NETs) are present in various tumors, their roles in tumor biology have not been clarified yet. In this study, we examined how NETs affect the pharmacokinetics and effects of doxorubicin (DOX). METHODS: NETs were generated by neutrophils stimulated with phorbol 12-myristate 13-acetate (PMA) or lipopolysaccharide (LPS). DOX was added to NETs and their distribution was observed under fluorescein microscopy, and the diffusion of DOX through 3 μM pores from lower to upper chambers was evaluated with a fluorescence-based assay. Ovarian cancer cells, KOC-2S and SKOV3, were embedded in collagen gel droplets and cultured in 3D way and their apoptosis was examined with flow cytometry. RESULTS: DOX was mostly co-localized with NETs. The transfer of DOX to upper chambers increased over time, which was significantly decreased by the presence of neutrophils stimulated with PMA or LPS in the lower chamber. DOX outside of the gel increased the rates of annexin V (+) apoptotic cells, which were significantly reduced by the addition of LPS-stimulated neutrophils in media both in KOC-2S and SKOV3. The reduced diffusion and apoptosis were mostly restored by the destruction of the NETs structure with 1000 u/ml DNAse I. CONCLUSION: NETs efficiently trap and inhibit the diffusion of DOX which may attenuate its ability to induce apoptosis of ovarian cancer cells. Degradation of NETs with DNAse I may augment the response of ovarian cancer to DOX.

Abstract Although preoperative chemoradiation therapy can down-stage locally advanced rectal cancer (LARC), it has little effect on distant metastases. Metformin exerts an anti-cancer effect partly through the activation of host immunity. LuM1, a highly lung metastatic subclone of colon 26, was injected subcutaneously (sc) in BALB/c mice and treated with metformin and/or local radiation (RT). Lung metastases and the primary tumors were evaluated and the phenotypes of immune cells in the spleen and lung metastases were examined with flow cytometry and immunohistochemistry. Local RT, but not metformin, partially delayed the growth of sc tumor which was augmented with metformin. Lung metastases were unchanged in metformin or RT alone, but significantly reduced in the combined therapy. The ratios of splenic T cells tended to be low in the RT group, which were increased by the addition of metformin. IFN-γ production of the splenic CD4(+) and CD8(+) T cells was enhanced and CD49b (+) CD335(+) activated NK cells was increased after combined treatment group. Density of NK cells infiltrating in lung metastases was increased after combination treatment. Metformin effectively enhances local and abscopal effects of RT though the activation of cell-mediated immunity and might be clinically useful for LARC.

BACKGROUND: Osteopenia is defined as low bone mineral density (BMD) and has been shown to be associated with outcomes of patients with various cancers. The association between osteopenia and perihilar cholangiocarcinoma is unknown. The aim of this study was to evaluate osteopenia as a prognostic factor in patients with perihilar cholangiocarcinoma. METHODS: A total of 58 patients who underwent surgery for perihilar cholangiocarcinoma were retrospectively analyzed. The BMD at the 11th thoracic vertebra was measured using computed tomography scan within one month of surgery. Patients with a BMD < 160 HU were considered to have osteopenia and b BMD ≥ 160 did not have osteopenia. The log-rank test was performed for survival using the Kaplan-Meier method. After adjusting for confounding factors, overall survival was assessed by Cox's proportional-hazards model. RESULTS: The osteopenia group had 27 (47%) more females than the non-osteopenia group (p = 0.036). Median survival in the osteopenia group was 37 months and in the non-osteopenia group was 61 months (p = 0.034). In multivariable analysis, osteopenia was a significant independent risk factor associated with overall survival in patients with perihilar cholangiocarcinoma (hazard ratio 3.54, 95% confidence interval 1.09-11.54, p = 0.036), along with primary tumor stage. CONCLUSIONS: Osteopenia is associated with significantly shorter survival in patients with perihilar cholangiocarcinoma.

【目的】高度肥満症患者に対する減量・代謝改善手術症例の治療効果を検討する。【方法】2010年7月から2021年3月までに当院で行った107回(103症例)の減量・代謝改善手術を対象とした。主に体重変化と糖尿病治療効果を後ろ向きに評価した。【結果】99症例がデータ解析可能であった。術後総体重減少率は、術後1年目で28.4%、2年目で28.3%、5年目で27.3%であり、約30%の体重減少効果を認めた。糖尿病患者は47例であり、HbA1cの推移は術前の6.8%±1.4から術後6ヵ月で5.9%(±0.8)、術後1年で5.8%(±0.93)と改善を認めた。糖尿病寛解率は、術後6ヵ月で65.9%、術後1年で76.5%、術後4年で50.0%であり、糖尿病患者の半数で寛解を認めた。術前インスリン非使用群でインスリン使用群より糖尿病寛解率が良好な傾向が認められた。また、術前mABCDスコアが高い症例ほど術後寛解度が高かった。【結語】当院での減量・代謝改善手術症例において比較的良好な減量効果・糖尿病治療効果が得られた。(著者抄録)

The prognosis of pancreatic ductal carcinoma (PDAC) with peritoneal metastasis remains dismal. Systemic chemotherapy alone may not be effective, and the combination of intraperitoneal chemotherapy with systemic chemotherapy is expected to prolong the overall survival in patients with peritoneal metastasis. We have designed a randomized phase III trial to confirm the superiority of intravenous (i.v.) and intraperitoneal (i.p.) paclitaxel (PTX) with S-1 relative to gemcitabine plus nab-PTX (GnP), which is the current standard therapy for patients with metastatic PDAC. A total of 180 patients will be accrued from 30 institutions within 3 years. Patients will be randomly assigned in a 1:1 ratio to receive either i.v. and i.p. PTX with S-1 or GnP (target of 90 patients per group). The primary endpoint is overall survival; secondary endpoints are progression-free survival, response rate, proportion with negative peritoneal washing cytology during chemotherapy, proportion requiring conversion surgery, and adverse event profiles. Japan Registry of Clinical Trials jRCTs051180199 ( https://jrct.niph.go.jp/ ).

Peritoneal dissemination is a major metastatic pathway for gastrointestinal and ovarian malignancies. The miR-29b family is downregulated in peritoneal fluids in patients with peritoneal metastases (PM). We examined the effect of miR-29b on mesothelial cells (MC) which play critical a role in the development of PM through mesothelial-mesenchymal transition (MMT). Human peritoneal mesothelial cells (HPMCs) were isolated from surgically resected omental tissue and MMT induced by stimulation with 10 ng/ml TGF-β1. MiR-29b mimics and negative control miR were transfected by lipofection using RNAiMAX and the effects on the MMT evaluated in vitro. HPMC produced substantial amounts of miR-29b which was markedly inhibited by TGF-β1. TGF-β1 stimulation of HPMC induced morphological changes with decreased expression of E-cadherin and calretinin, and increased expression of vimentin and fibronectin. TGF-β1 also enhanced proliferation and migration of HPMC as well as adhesion of tumor cells in a fibronectin dependent manner. However, all events were strongly abrogated by simultaneous transfection of miR-29b. MiR-29b inhibits TGF-β1 induced MMT and replacement of miR-29b in the peritoneal cavity might be effective to prevent development of PM partly through the effects on MC.

Background: The peritoneal cavity contains many site-specific immune cells which constitute a unique immune microenvironment. However, it is unclear how the local immune signature is altered in patients with peritoneal metastases (PM). Methods: Peritoneal lavage fluid or ascites were obtained from 122 patients with various stages of gastric cancer (GC). Cells recovered from peritoneal fluids were immunostained with mAbs for lymphocyte-, macrophage- and tumor cell-specific antigens and the frequencies of leukocyte subsets and antigen expression levels were evaluated with multi-color flowcytometry. Results: The proportions of CD8(+) T cells, CD3(+)CD56(+) NKT-like cells, and CD3(-)CD56(+) NK cells to CD45(+) leukocytes were significantly reduced in patients with PM compared to those without PM. In patients with PM, the rates of CD8 (+) T cells and NKT-like cells correlated inversely with the tumor leukocyte ratio (TLR), the relative frequency of CD326(+) tumor cells to CD45(+) leukocytes. In contrast, the proportion of CD19(+) B cells was significantly increased in patients with PM, and their proportion correlated positively with the TLR and peritoneal carcinomatosis index (PCI) score. In patients with PM, CD14(+) macrophages tended to be increased with enhanced expression of CD14, CD16 and a M2-macrophage marker, CD163. In particular, macrophages in patients with high TLR contained many granules with high side scatter and CD14 expression in their flow profile compared to those without PM. Conclusion: PM are accompanied by a drastic change in phenotypes of lymphocyte and macrophage in the peritoneal cavity, which might be involved in the development and progression of intraperitoneal tumor growth.