Down-regulated expression of RhoA in human conventional renal cell carcinoma

Background: Renal cell carcinoma (RCC) is the most common cancer in adult kidney. Delayed diagnosis may result in progression and metastasis. Markers for early detection of RCC are lacking. The small GTPase RhoA has been implicated in the regulation of cell morphology, motility and transformation, but the role of RhoA in tumorigenesis of RCC remains unclear. In this study, the significance of RhoA expression in human RCC was characterized. Materials and Methods: RhoA mRNA and protein expressions were examined by real-time polymerase chain reaction (PCR) and immunohistochemistry respectively in 46 pairs of tissues. Results: Real-time PCR revealed that RhoA mRNA expression was significantly lower in cancerous as compared to normal tissues (p=0.036). RhoA protein expression was significantly higher in normal than in cancerous tissues (p=0.032). However, RhoA expression did not correlate with age, differentiation grade or TNM stage (all p>0.05). Conclusion: RhoA down-regulation may be involved in human renal tumorigenesis.