POFUT1 and PLAGL2 are characteristic markers of mucinous colorectal cancer associated with MUC2 expression.

Colorectal mucinous adenocarcinoma (MAC) is one of the most lethal histological types of colorectal cancer, and its mechanism of development is not well understood. In this study, we aimed to clarify the molecular characteristics of MAC via in silico analysis using The Cancer Genome Atlas database. The expression of genes on chromosome 20q (Chr20q) was negatively associated with the expression of MUC2, which is a key molecule that can be used to distinguish between MAC and nonmucinous adenocarcinoma (NMAC). This was consistent with a significant difference in copy number alteration of Chr20q between the two histological types. We further identified 475 differentially expressed genes (DEGs) between MAC and NMAC, and some of the Chr20q genes among the DEGs are considered to be pivotal genes used to define MAC. Both in vitro and in vivo analysis showed that simultaneous knockdown of POFUT1 and PLAGL2, both of which are located on Chr20q, promoted MUC2 expression. Moreover, these genes were highly expressed in NMAC but not in MAC according to the results of immunohistological studies using human samples. In conclusion, POFUT1 and PLAGL2 are considered to be important for defining MAC, and these genes are associated with MUC2 expression.

Real-world application of next-generation sequencing-based test for surgically resectable colorectal cancer in clinical practice.

Aim: To evaluate the significance of next-generation sequencing-based gene panel testing in surgically resectable colorectal cancer by analyzing real-world data. Materials & methods: A total of 107 colorectal cancer patients who underwent curative surgery were included, and correlations between next-generation sequencing data and clinicopathological findings were evaluated. Results: More combination patterns in gene alteration were identified in advanced-stage tumors than in early-stage tumors. The copy number alteration count was significantly lower in right-sided colon tumors and early-stage tumors. Homologous recombination deficiency was more often identified in advanced-stage tumors, and high homologous recombination deficiency status was useful for identifying high-risk stage II tumors. Conclusion: Homologous recombination deficiency was identified as a useful result of gene panel testing with novel utility in clinical practice.

Angiopoietin-like 4 promotes glucose metabolism by regulating glucose transporter expression in colorectal cancer.

PURPOSE: Angiopoietin-like 4 (ANGPTL4) was recently shown to be associated with cancer progression but little is known about its contribution to cancer metabolism. The purpose of this study was to elucidate the role of ANGPTL4 in glucose metabolism in colorectal cancer (CRC). METHODS: Immunohistochemical staining of CRC specimens classified 84 patients into two groups according to ANGPTL4 expression. Clinicopathological characteristics, gene mutation status obtained by next-generation sequencing, and fluorodeoxyglucose (FDG) uptake measured by positron emission tomography/computed tomography (PET/CT) were compared between the two groups. Furthermore, the impact of ANGPTL4 expression on cancer metabolism was investigated by a subcutaneous xenograft mouse model using the ANGPTL4 knockout CRC cell line, and glucose transporter (GLUT) expression was evaluated. RESULTS: There were significantly more cases of T3/4 tumours (94.3% vs. 57.1%, P < 0.001) and perineural invasion (42.9% vs. 22.4%, P = 0.046) in the ANGPTL4-high group than in the low group. Genetic exploration revealed a higher frequency of KRAS mutation (54.3% vs. 22.4%, P = 0.003) in the ANGPTL4-high tumours. All the FDG uptake parameters were significantly higher in ANGPTL4-high tumours. In vivo analysis showed a significant reduction in tumour size due to ANGPTL4 knockout with lower expression of GLUT1 and GLUT3, and suppression of AKT phosphorylation. CONCLUSION: ANGPTL4 regulates the expression of GLUTs by activating the PI3K-AKT pathway and thereby promoting glucose metabolism in CRC. These findings establish a new functional role of ANGPTL4 in cancer progression and lay the foundation for developing a novel therapeutic target.

Short-term and midterm outcomes of single-incision laparoscopic surgery for right-sided colon cancer.

INTRODUCTION: The purpose of this study was to clarify the usefulness of SILS for right-sided colon cancer by evaluating the short-term and midterm outcomes. METHODS: Between 2012 and 2017, 65 selected patients with right-sided colon cancer underwent ileocecal resection, right hemicolectomy, or transverse colectomy; all were enrolled in the study. The same well-trained surgeon performed each procedure by using a multi-instrument access port with three channels, which was placed at the umbilicus via an approximately 3-cm skin incision. RESULTS: The pathological disease stage distribution was stage 0, 4 cases; stage I, 23 cases; stage II, 19 cases; stage III, 17 cases; and stage IV, 2 cases. The surgical procedures performed were ileocecal resection, 23 cases; right hemicolectomy, 35 cases; and transverse colectomy, 7 cases. The median operative time and intraoperative blood loss were 216 min and 10 mL, respectively. Although 18 cases needed additional ports, none required conversion to open surgery. The median number of harvested lymph nodes was 24. No major perioperative morbidities occurred in this patient series. The median postoperative hospital stay was 7 days. The median follow-up period was 30 months, and the 3-year relapse-free and overall survival rates were 100% and 100%, respectively, in the stage 0-I cases and 89% and 96% in the stage II-III cases, respectively. CONCLUSION: We concluded that SILS is as feasible as multiport laparoscopic surgery and a reliable surgical option in selected cases of right-sided colon cancer.