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The repair of DNA damage caused by chemotherapy in cancer cells occurs mainly at two cell cycle checkpoints (G

The best surgical technique for rectal cancer invading the prostate remains controversial. Rectal resection with en bloc prostatectomy using a standard retropubic approach is an option but has disadvantages. We report a new surgical procedure applying Retzius-sparing robot-assisted radical prostatectomy.First, the rectum was mobilized mainly at its dorsal side. Next, the prostate was separated from the bladder and urethra via the pouch of Douglas approach without opening the Retzius cavity, after which the surgical specimen was extracted through the perineal wound. Lateral pelvic lymph node dissection was performed after vesicourethral anastomosis.This new robotic procedure minimizes surgical trauma and preserves normal pelvic anatomy. Furthermore, this approach makes it easy to perform subsequent lateral pelvic lymph node dissection.

The patient was a 62-year-old man in whom 0-Ⅱa plus Ⅱc lesions in Rs were identified during follow-up observation of multiple colorectal polyps that were found during colonoscopy performed for the examination of fecal occult blood. CT showed no lymphadenopathy or distant metastasis to other organs. Laparoscopic-assisted high anterior resection of the rectum was performed with a diagnosis of clinical stage Ⅰ. Pathologically, there was a well-to-moderately differentiated tubular adenocarcinoma that remained in the lamina propria; however, 1 metastasis was found in the lymph node adjacent to the rectum(#251). Therefore, adjuvant chemotherapy was performed for 6 months after the operation, and 5 years have passed with no recurrence. Here, we report a case with no apparent submucosal invasion but with lymph node metastasis. We confirm recurrence-free survival for 5 years after surgery.

The acquisition of resistance to apoptosis is one of the biggest problems in colorectal cancer (CRC) treatment. This study aimed to elucidate the mechanisms of resistance to apoptosis with a focus on interleukin (IL)-6 produced by the interaction between cancer cells and cancer-associated fibroblasts (CAFs).DLD-1 and HCT116 cell lines were treated with IL-6 and furthermore co-cultured with CAFs. The expression levels of Bcl-xL, Mcl-1 and phosphorylation of STAT3 were evaluated by western blotting. We also performed immunostaining for CRC specimens and evaluated the correlation between CAFs invasion and Bcl-xL/Mcl-1 expression.Both IL-6 and co-culturing enhanced Bcl-xL, Mcl-1 and the phosphorylation of STAT3. Immunohistochemistry showed a positive correlation between CAFs and Bcl-xL/Mcl-1. These results showed that the interaction between CAFs and cancer cells enhances Bcl-xL and Mcl-1 through the IL-6/STAT3 signaling pathway.Our findings provide new potential therapeutic targets and strategies for CRC treatment.

The cancer-stromal interaction has been demonstrated to promote tumor progression, and cancer-associated fibroblasts (CAFs), which are the main components of stromal cells, have attracted attention as novel treatment targets. Chitinase 3-like 1 (CHI3L1) is a chitinase-like protein, which affects cell proliferation and angiogenesis. However, the mechanisms through which cells secrete CHI3L1 and through which CHI3L1 mediates tumor progression in the cancer microenvironment are still unclear. Accordingly, the present study assessed the secretion of CHI3L1 in the microenvironment of colorectal cancer and evaluated how CHI3L1 affects tumor angiogenesis. CAFs and normal fibroblasts (NFs) established from colorectal cancer tissue, and human colon cancer cell lines were evaluated using immunostaining, cytokine antibody array, RNA interference, reverse transcription-quantitative PCR (RT-qPCR), ELISA, western blotting and angiogenesis assays. The expression and secretion of CHI3L1 in CAFs were stronger than those in NFs and colorectal cancer cell lines. In addition, interleukin-13 receptor α2 (IL-13Rα2), a receptor for CHI3L1, was not expressed in colorectal cancer cell lines, but was expressed in fibroblasts, particularly CAFs. Furthermore, the expression and secretion of IL-8 in CAFs was stronger than that in NFs and cancer cell lines, and recombinant CHI3L1 addition increased IL-8 expression in CAFs, whereas knockdown of CHI3L1 suppressed IL-8 expression. Furthermore, IL-13Rα2 knockdown suppressed the enhancement of IL-8 expression induced by CHI3L1 treatment in CAFs. For vascular endothelial growth factor-A (VEGFA), similar results to IL-8 were observed in an ELISA for comparison of secretion between CAFs and NFs and for changes in secretion after CHI3L1 treatment in CAFs; however, no significant differences were observed for changes in expression after CHI3L1 treatment or IL-13Rα2 knockdown in CAFs assessed using RT-qPCR assays. Angiogenesis assays revealed that tube formation in vascular endothelial cells was suppressed by conditioned medium from CAFs with the addition of human CHI3L1 neutralizing antibodies compared with control IgG, and also suppressed by conditioned medium from CAFs transfected with CHI3L1, IL-8 or VEGFA small interfering RNA compared with negative control small interfering RNA. Overall, the present findings indicated that CHI3L1 secreted from CAFs acted on CAFs to increase the secretion of IL-8, thereby affecting tumor angiogenesis in colorectal cancer.

Immune checkpoint inhibitors(nivolumab)have been recommended as third-line chemotherapy for advanced gastric cancer(AGC)according to the Guidelines of Gastric Cancer(5th edition). Therefore, they have been used in daily clinical practice. On the other hand, the neutrophil-lymphocyte ratio(NLR)has been reported to be associated with the prognosis of cancer patients.Twenty patients treated with nivolumab for AGC between January 2018 and November 2019 were retrospectively examined.Median age of the 20 patients(18 males, 2 females)was 70 years(55- 84 years). Nivolumab was administered as second-, third-, fourth-, and fifth-line therapy in 1, 11, 7, and 1 case, respectively. The best tumor response evaluation was observed in PR 1, SD 7 and PD 10 cases. Median overall survival(OS)was 10 months, and median progression-free survival(PFS)was 3 months. No serious adverse events occurred. Compared to the NLR2.0 group, OS significantly prolonged(2.2 months vs 21.9 months)and PFS tended to prolong(1.4 months vs 6.2 months)in the NLR≤2.0 group.NLR may be an effective prognostic factor in patients with AGC receiving nivolumab treatment.