CD133 mRNA expression and microsatellite instability in colorectal carcinoma.

摘要

OBJECTIVE: The present study was performed to examine the CD133 expression in colorectal cancer and to analyze its relationship with microsatellite instability (MSI) and the clinicopathological factors, including patient survival. METHODS: The CD133 mRNA levels in 61 primary colorectal adenocarcinomas were analyzed by reverse transcriptase-polymerase chain reaction, with normalization relative to GAPDH. Five microsatellite markers were analyzed to evaluate MSI. RESULTS: A CD133 mRNA expression was significantly associated with the depth of invasion (P = 0.017), lymph node involvement (P = 0.012), and lymphovascular invasion (P = 0.019). A CD133 expression was significantly correlated with the MSI status (P = 0.035). With a median follow-up period of 45 months, the 5-year disease-free survival rate of patients with a low CD133 mRNA expression was significantly higher than that of those patients with high levels of CD133 mRNA expression (82.9% and 59.0%, respectively; P = 0.027). However, on the multivariate analysis, a CD133 mRNA expression was not an independent predictor of disease-free survival. CONCLUSIONS: Elevated CD133 mRNA levels may represent more aggressive tumor biology and poorer survival in patients with colorectal cancer, correlating with a high level of MSI status. Larger prospective studies are required to confirm these findings.