RIPK4 Promotes Cell Invasion and the Epithelial-Mesenchymal Transition in Ovarian Cancer.

OBJECTIVE: To investigate the clinical role and biological function of receptor-interacting protein kinase 4 (RIPK4) in ovarian cancer (OC). METHODS: We conducted a comprehensive analysis of the expression and prognostic role of RIPK4 in OC using various public databases including The Cancer Genome Atlas, Oncomine, and Kaplan-Meier plotter. In vitro studies included wound healing, cell migration and invasion, cell proliferation, and cell apoptosis assays as well as vascular mimicry experiments. In vivo studies were conducted using subcutaneous and intraperitoneal xenografts. RESULTS: Our findings revealed that RIPK4 was significantly overexpressed in OC tissue compared to normal ovarian tissue. Moreover, the overexpression of RIPK4 was associated with advanced-stage disease and a poor prognosis in OC patients. RIPK4 silencing resulted in significant inhibition of intraperitoneal tumor growth, invasion, and vascular mimicry in OC cells. Furthermore, downregulation of RIPK4 inhibited the epithelial-mesenchymal transition of OC cells both in vitro and in vivo by promoting the expression of E-cadherin and inhibiting the expression of N-cadherin. CONCLUSION: The results of this study suggest that RIPK4 may function as an oncogene in the development and prognosis of OC.

Association between CXCR2 and IL-22BP expression indicate a poor outcome for gastric adenocarcinoma progression.

C-X-C motif chemokine receptor type 2 (CXCR2), a key regulatory protein, has been associated with multiple roles in the progression of numerous tumors, including gastric adenocarcinoma (GA). However, the mechanism of CXCR2 in the development of tumors remains controversial and unclear. In a previous study, the expression of CXCR2 and interleukin-22 receptor 2 (IL-22BP) was observed in GA. This promoted the present study, which aimed to explore the association between the two proteins, and to further analyze their roles in GA. CXCR2 and IL-22BP protein expression was analyzed by immunohistochemistry and reverse transcription-quantitative polymerase chain reaction assays in gastric cancer (GC) tissue, additionally confirmed via western blotting and immunocytochemical analysis in the MKN-45, BGC-823 and SGC-7901 cell lines. The association between expression levels and clinicopathological characteristics was evaluated by the Mann-Whitney U and Kruskal-Wallis tests. Using Kaplan-Meier plots and Cox proportional hazard models, overall survival (OS) was analyzed. Compared with non-cancerous tissue, CXCR2 and IL-22BP were over expressed (P<0.001 and P<0.001, respectively), and were observed mainly in the cytoplasm (P=0.022 and P=0.014, respectively) in GA. The associated protein and messenger RNA levels were analyzed, and coexpression was identified. Increased expression and more positive cases of CXCR2 and IL-22BP were observed with advanced pathological tumor-node-metastasis (p-TNM) stage in GC (P<0.001 and P<0.001, respectively), as well as the presence and absence of lymph node metastasis (LNM) (P=0.003 and P=0.041, respectively) and deep or superficial muscular invasion (P=0.002 and P=0.004, respectively). In addition, an association between IL-22BP and tumor diameter was indicated (P=0.021). In a Kaplan-Meier analysis, compared with negative expression, the two proteins identified a group of patients with the shortest OS. Cox proportional hazard models revealed that the two proteins, in addition to p-TNM stage, LNM and depth of invasion, predicted a short time to OS. The coexpression of CXCR2 and IL-22BP was demonstrated in GA, which may indicate that CXCR2 is involved in more complex mechanisms and roles, and indicate a poor outcome in GA progression.

Loss of stromal caveolin-1 expression in colorectal cancer predicts poor survival.

AIM: To investigate the clinicopathological significance and prognostic value of caveolin-1 (CAV-1) in both tumor and stromal cells in colorectal cancer (CRC). METHODS: A total of 178 patients with CRC were included in this study. The correlation between CAV-1 expression and clinicopathologic features and survival was studied. RESULTS: CAV-1 expression was detected in tumor and stromal cells. The expression of stromal CAV-1 was closely associated with histological type (P=0.022), pathologic tumor-node-metastasis stage (P=0.047), pathologic N stage (P=0.035) and recurrence (P=0.000). However, tumor cell CAV-1 did not show any correlation with clinical parameters. Additionally, the loss of stromal CAV-1 expression was associated with shorter disease-free survival (P=0.000) and overall survival (P=0.000). Multivariate analysis revealed that the loss of stromal CAV-1 expression was an independent prognostic factor for both overall survival (P=0.014) and disease-free survival (P=0.006). CONCLUSION: The loss of stromal CAV-1 expression in CRC was associated with poor prognosis and could be a prognostic factor for CRC patients.

Transanal natural orifice specimen extraction for laparoscopic anterior resection in rectal cancer.

AIM: To investigate whether transanal natural orifice specimen extraction (NOSE) is a better technique for rectal cancer resection. METHODS: A prospectively designed database of a consecutive series of patients undergoing laparoscopic low anterior resection for rectal cancer with various tumor-node-metastasis classifications from March 2011 to February 2012 at the First Affiliated Hospital of Sun Yat-Sen University was analyzed. Patient selection for transanal specimen extraction and intracorporeal anastomosis was made on the basis of tumor size and distance of rectal lesions from the anal verge. Demographic data, operative parameters, and postoperative outcomes were assessed. RESULTS: None of the patients was converted to laparotomy. Respectively, there were 16 cases in the low anastomosis and five in the ultralow anastomosis groups. Mean age of the patients was 45.4 years, and mean body mass index was 23.1 kg/m². Mean distance of the lower edge of the lesion from the anal verge was 8.3 cm. Mean operating time was 132 min, and mean intraoperative blood loss was 84 mL. According to the principle of rectal cancer surgery, we performed D2 lymph node dissection in 13 cases and D3 in eight. Mean lymph nodes harvest was 17.8, and the number of positive lymph nodes was 3.4. Median hospital stay was 6.7 d. No serious postoperative complication occurred except for one anastomotic leakage. All patients remained disease free. Mean Wexner score was 3.7 at 11 mo after the operation. CONCLUSION: Transanal NOSE for total laparoscopic low/ultralow anterior resection is feasible, safe and oncologically sound. Further studies with long-term outcomes are needed to explore its potential advantages.

[Low and ultralow anterior resection with hand-assisted laparoscopic surgery for rectal cancer].

OBJECTIVE: To summarize the experience and short-term clinical outcomes of hand-assisted laparoscopic surgery (HALS) in sphincter-preserving surgery for low and ultralow rectal cancer. METHODS: Data of 49 patients with rectal cancer who underwent HALS for low or ultralow anterior resection between January 2010 and January 2011 were analyzed retrospectively. RESULTS: The proximal resection margin was (14.3±6.9) cm and the distal margin was(4.3±1.9) cm. The mean operative time was(128.3±70.9) min. On postoperative macroscopic evaluation, the mesorectum was intact in 42 cases, nearly intact in 7 cases. The circumferential resection margin was more than 2 mm in 42 cases, and less than 2 mm in 7 cases. Forty-six patients underwent R0 resection, and 3 cases underwent R1 resection. The median retrieved lymph node (LN) was 16.20±9.23, and the median positive LN was 1.12±2.19. Postoperative pathological examination showed TNM stage was I( in 12 patients, II(A in 18, II(B in 1, III(A in 2, III(B in 8, III(C in 5, IIII( in 3. The median postoperative hospital stay was (6.25±3.87) d. There were no anastomotic leakage, ileus, intra-abdominal or anastomotic bleeding. There were two wound infections. CONCLUSION: Low and ultralow anterior resection for rectal cancer using HALS approach is safe and feasible with favorable short-term outcome.