MiR-92a Promotes Cell Metastasis of Colorectal Cancer Through PTEN-Mediated PI3K/AKT Pathway

MicroRNAs regulate gene expression at the posttranscriptional level and play important roles in tumor development, progression, and metastasis. The aim of this study was to investigate the role of microRNA-92a (miR-92a) in metastasis of colorectal cancer (CRC). One hundred fifty-eight CRC patients were enrolled. The expression of miR-92a, PTEN, and E-cadherin was analyzed by real-time PCR. Univariate (Kaplan-Meier) analysis was used to analyze primary outcomes included 5-year overall survival and tumor recurrence. CRC cell model studies were used to analyze the miR-92a-involved CRC metastasis. The expression of miR-92a in tumor tissues was significantly positively correlated with lymph node metastasis in CRC patients (p = 0.012). After adjusting for age, sex, and disease differentiation, this correlation remained significant (p = 0.01). In addition, there was a negative correlation between levels of miR-92a and the PTEN gene (p < 0.0001). No any association of miR-92a and E-cadherin was found (p = 0.128). Patients with high miR-92a/low PTEN had poorer overall survival and disease-free survival rates than those with high miR-92a/high PTEN, low miR-92a/high PTEN, and low miR-92a/low PTEN. The association of levels of miR-92a and PTEN with tumor cell migration in CRC was also confirmed in CRC cell models. We suggest that miR-92a is involved in lymph node metastasis of CRC patients through PTEN-regulated PI3K/AKT signaling pathway.