Objective  To investigate the expression of Rab27A in colorectal cancer (CRC) at the gene and protein level, and analyze its correlation with clinical characteristics.

Methods  From January 2005 to January 2019, 125 patients with CRC who received operation at the Department of General Surgery of Shanghai Pudong New Area People's Hospital and the Department of Gastrointestinal Surgery of Renji Hospital, Shanghai Jiao Tong University School of Medicine were included, the CRC pathological specimens and clinical data of the patients were retrospectively analyzed. Quantitative real-time polymerase chain reaction (qRT-PCR) and Western blotting analyses were used to detect the expression of Rab27A mRNA and protein in tumor tissues and corresponding adjacent tissues (more than 5 cm from the edge of cancer tissues) of 32 and 8 pairs of CRC patients, respectively. The expression of Rab27A in 125 cases of CRC was examined by immunohistochemistry (IHC). The correlation between Rab27A expression and clinical characteristics in 125 cases of CRC were then analyzed.

Results  The expression level of Rab27A mRNA in tumor tissues was significantly higher than that in adjacent normal tissues (P=0.001). In 8 pairs of colorectal cancer tissues and adjacent tissues, the protein expression level in tumor tissues was significantly higher than that in adjacent normal tissues (P=0.037、0.017). It showed that high expression of Rab27A was significantly correlated with tumor size and clinical stage. Survival analysis results suggested that CRC patients with overexpression of Rab27A protein had shorter overall survival. Multivariate Cox regression analysis showed that Rab27A expression might be an independent prognostic factor for CRC.

Conclusions  Rab27A plays an important role in the occurrence and development of CRC, and can be used as a potentially effective indicator reflecting the biological behavior of CRC.