Although the cancer stem cell (CSC) concept has provided a reasonable explanation for cancer recurrence following chemotherapy, the relationship between CSCs and chemotherapy resistance has not been thoroughly investigated, especially in solid tumors. We aimed to identify the mechanism underlying colorectal cancer (CRC) chemoresistance focusing on the cell cycle mediator F-Box/WD repeat domain-containing 7 (FBXW7). From 55 consecutive CRC cases who underwent neoadjuvant chemotherapy (NAC) or neoadjuvant chemoradiotherapy (NACRT) at Kyoto University Hospital, pre-treatment endoscopic biopsy specimens were collected and divided into two groups upon immunohistochemical (IHC) analysis: 21 cases of FBXW7 high expression (FBXW7-high group) and 34 cases of low expression (FBXW7-low group). High FBXW7 expression in pre-treatment biopsy specimen was significantly associated with poor pathological therapeutic effect (p = 0.019). The proportion of FBXW7-positive cells in surgically resected CRC specimens from patients who underwent NAC or NACRT was significantly higher than that in the pre-treatment biopsy specimens (p < 0.001). The expression of FBXW7 was inversely correlated with that of Ki67 in both pre-treatment biopsy specimens and surgically resected specimens. FBXW7 expression in the EpCAM^high/CD44^high subpopulation isolated by flow cytometry from CRC samples was significantly higher than that in the EpCAM^high/CD44^low subpopulation. Cell-cycle analysis in CRC cell lines revealed that, upon FBXW7 silencing, the proportion of G0/G1 cells was significantly lower than that in control cells. Moreover, knockdown of FBXW7 in CRC cell lines increased the sensitivity to anti-cancer drugs in vitro and in vivo. A subset of CRC stem cells possesses chemoresistance through FBXW7 expression. Cell cycle arrest induced by FBXW7 expression should be considered as a potential therapeutic target to overcome chemoresistance in CRC stem cell subsets.

A lack of caudal-type homeobox transcription factor 2 (CDX2) protein expression has been proposed as a prognostic biomarker for colorectal cancer (CRC). However, the relationship between CDX2 levels and the survival of patients with stage II/III CRC along with the relationship between microRNAs (miRs) and CDX2 expression are unclear. Tissue samples were collected from patients with stage II/III CRC surgically treated at Kyoto University Hospital. CDX2 expression was semi-quantitatively evaluated by immunohistochemistry (IHC). The prognostic impacts of CDX2 expression on overall survival (OS) and relapse-free survival (RFS) were evaluated by multivariable statistical analysis. The expression of miRs regulating CDX2 expression and their prognostic impacts were analyzed using The Cancer Genome Atlas Program for CRC (TCGA-CRC). Eleven of 174 CRC tissues lacked CDX2 expression. The five-year OS and RFS rates of patients with CDX2-negative CRC were significantly lower than those of CDX2-positive patients. Multivariate analysis of clinicopathological features revealed that CDX2-negative status is an independent marker of poor prognosis in stage II/III CRC. miR-9-5p was shown to regulate CDX2 expression. TCGA-CRC analysis showed that high miR-9-5p expression was significantly associated with poor patient prognosis in stage II/III CRC. In conclusion, CDX2, the post-transcriptional target of microRNA-9-5p, is a useful prognostic biomarker in patients with stage II/III CRC.

Background: Foramen of Winslow hernia (FWH) is a rare but emergent condition caused by an increase in the foramen diameter, visceral mobility, and intra-abdominal pressure. To the best of our knowledge, this is the first study to report a case of FWH secondary to large uterine fibroids that was successfully treated with laparoscopic surgery. Case presentation: A 52-year-old woman with large uterine fibroids was diagnosed with FWH. Because of the absence of signs of bowel ischemia and peritonitis, we performed an elective laparoscopic surgery through a 5-port system after bowel decompression using a long intestinal tube. Although foramen of Winslow closure was not performed, her postoperative course was uneventful. Conclusions: Laparoscopic surgery for FWH is considered an extremely effective surgical treatment option because of its safety and efficacy in performing delicate procedures (such as adhesiolysis) with a good magnified field of view.

The enhanced-view totally extraperitoneal (eTEP) technique, an endoscopically performed Rives-Stoppa method, has been used extensively for ventral hernia repairs. However, in this technique, the necessity of posterior rectus sheath re-approximation and mesh fixation remains unclear. There are a few reports of post-eTEP interparietal hernias (IHs) occurring because of dehiscence of the re-approximated posterior rectus sheath; however, IH secondary to mesh migration is rare. Herein, we report a rare case of IH due to mesh migration after eTEP repair for an incisional hernia. A 70-year-old man underwent eTEP repair for an incisional hernia using a self-gripping mesh without mesh fixation and posterior rectus sheath re-approximation one year previously, developed an IH. An elective laparoscopic surgery revealed an orifice to the retrorectus space as though the IH sac between the retrorectus muscle and the posterior layer including the bilateral posterior rectus sheaths, peritoneum, and mesh. We placed eight transmural sutures with 0 nylon thread and closed the orifice. The patient was then discharged on postoperative day two and was asymptomatic at 24 months without evidence of ventral hernia recurrence. We consider that strenuous activity and deep bending may cause mesh migration or dislocation. If that occurs in the early post-eTEP period without posterior rectus sheaths closure, the vulnerable peritoneal area will be exposed, which consider to be an IH orifice. Even after using the self-gripping mesh in eTEP repair, mesh fixation remains the best option to prevent postoperative complications, including IH.