Expression of RhoA and RhoC in colorectal carcinoma and its relations with clinicopathological parameters

Ras homologous (Rho) family GTPases play a pivotal role in the regulation of numerous cellular functions associated with malignant transformation and metastasis. To evaluate the role of these GTPases in colorectal cancer, the mRNA expression levels in matched sets of tumor and non-tumor tissues from surgical specimens were analyzed. The relationship between the mRNA levels in tumor tissues to the clinicopathological features was also assessed.

A total of 68 patients with colorectal carcinoma were recruited and the levels of RhoA and RhoC mRNA transcripts in cancer, paratumoral and normal tissues were characterized by quantitative real-time polymerase chain reaction (QRT-PCR). Their correlation to clinical histopathological parameters was analyzed.

The levels of RhoA and RhoC mRNA transcripts in carcinoma tissues were significantly higher than those in the matched paratumor and normal tissues from the same patient (p<0.05). The expression levels of both genes were significantly correlated with metastasis of cancer cells to lymph nodes and liver (p<0.05). The levels of RhoA expression were significantly correlated with the histopathological degree of cancer, while the expression of RhoC was correlated with the extent of local invasion to intestine.

This is the first study with QRT-PCR to examine the expressions of RhoA and RhoC genes in colorectal carcinoma of Chinese patients. The significantly up-regulated RhoA and RhoC expressions suggest that they may contribute to the initiation, development, invasion and metastasis of colorectal carcinoma in Chinese patients.