Aberrant expression of Rab1A and its prognostic significance in human colorectal cancer.

OBJECTIVE: Colorectal cancer (CRC) is one of the most common types of cancer worldwide. Emerging evidence has verified that Rab1A plays an oncogenic role in several human malignancies including breast cancer, lung cancer, and hepatocellular carcinomas. However, the clinical significance and prognostic impact of Rab1A in CRC is still unclear.

PATIENTS AND METHODS: We initiated our investigation by immunohistochemistry and Western blot analysis to confirm Rab1A expression in CRC tissues. Meanwhile, the correlation of Rab1A expression and clinicopathologic features, as well as outcome in CRC patients, were retrospectively analyzed.

RESULTS: In the issue, Rab1A is overexpressed in CRC tissues compared with matched noncancerous tissues. Meanwhile, high Rab1A expression was significantly associated with the TNM stage, lymph node metastasis, and peritoneal metastasis. In addition, multivariate analyses identified Rab1A expression and TNM stage as independent predictors for CRC patients. Moreover, Kaplan-Meier survival analysis showed that patients with high Rab1A expression had a significantly worse survival time than those with low Rab1A expression, which especially affected the survival in CRC patients with advanced stage. Spearman analysis suggested that there was a positive relationship between Rab1A expression and preoperative serum carcinoembryonic antigen (CEA) for CRC patients.

CONCLUSIONS: These results suggested that Rab1A is an important diagnostic marker for CRC, and Rab1A can be used as a valuable biomarker for prognosis as well as peritoneal metastasis in CRC patients. Rab1A may prove to be clinically useful for developing a new therapeutic target of CRC treatment.