Decreased expression of miR-133a correlates with poor prognosis in colorectal cancer patients

AIM: To investigate microRNA-133a (miR-133a) expression in colorectal cancer (CRC) and its relationship with tumorigenesis and disease prognosis.

Krüppel-like factor 8 overexpression is correlated with angiogenesis and poor prognosis in gastric cancer

AIM:To investigate Krüppel-like factor 8 (KLF8) expression in gastric cancer and its relationship with angiogenesis and prognosis of gastric cancer. METHODS:One hundred and fifty-four patients with gastric cancer who underwent successful curative resection were retrospectively enrolled in the study. Fifty tumor-adjacent healthy gastric tissues (≥ 5 cm from the tumor margin) obtained during the original resection were randomly selected for comparative analysis. In situ expression of KLF8 and CD34 proteins were examined by immunohistochemistry. The intratumoral microvessel density (MVD) was determined by manually counting the immunostained CD34-positive endothelial cells in three consecutive high-magnification fields (× 200). The relationship between differential KLF8 expression and MVD was assessed using Spearman's correlation coefficient test. χ2 test was performed to evaluate the effects of differential KLF8 expression on clinicopathologic factors. Kaplan-Meier and multivariate Cox survival analyses were used to assess the prognostic value of differential KLF8 expression in gastric cancer. RESULTS:Significantly higher levels of KLF8 protein were detected in gastric cancer tissues than in the adjacent non-cancerous tissues (54.5% vs 34.0%, P < 0.05). KLF8 expression was associated with tumor size (P < 0.001), local invasion (P = 0.005), regional lymph node metastasis (P = 0.029), distant metastasis (P = 0.023), and tumor node metastasis (TNM) stage (P = 0.002), as well as the MVD (r = 0.392, P < 0.001). Patients with KLF8 positive expression had poorer overall survival (P < 0.001) and cancer-specific survival (P < 0.001) than those with negative expression. Multivariate analysis demonstrated that KLF8 expression independently affected both overall and cancer-specific survival of gastric cancer patients (P = 0.035 and 0.042, respectively). CONCLUSION:KLF8 is closely associated with gastric tumor progression, angiogenesis and poor prognosis, suggesting it may represent a novel prognostic biomarker and therapeutic target for gastric cancer.

miR-422a is an independent prognostic factor and functions as a potential tumor suppressor in colorectal cancer

AIM: To determine the expression of mi R-422 a in colorectal cancer(CRC) tissues and to further explore the prognostic value and function of mi R-422 a in CRC carcinogenesis.METHODS: mi R-422 a expression was analyzed in 102 CRC tissues and paired normal mucosa adjacent to carcinoma by quantitative real-time PCR. The relationship of mi R-422 a expression with clinicopathological parameters was also analyzed. Kaplan-Meier analysis and Cox multivariate analysis were performed to estimate the potential role of mi R-422 a. Cell proliferation, migration, and invasion were used for in vitro functional analysis of mi R-422 a.RESULTS: The levels of mi R-422 a were dramatically reduced in CRC tissues compared with normal mucosa(P < 0.05), and significantly correlated with local invasion(P = 0.004) and lymph node metastasis(P < 0.001). Kaplan-Meier survival and Cox regression multivariate analyses revealed that mi R-422 a expression(HR = 0.568, P = 0.015) and clinical TNM stage(HR = 2.942, P = 0.003) were independent prognostic factorsfor overall survival in CRC patients. Furthermore, in vitro experiments showed that overexpression of mi R-422 a inhibited the proliferation, migration, and invasion of SW480 and HT-29 cells.CONCLUSION: Down-regulation of mi R-422 a may serve as an independent prognosis factor in CRC. Mi R-422 a functions as a tumor suppressor and regulates progression of CRC.