The relationship between RGS5 expression and cancer differentiation and metastasis in non-small cell lung cancer

Background: Regulator of G-protein signaling 5 (RGS5), a tissue-specific signal regulating molecular, plays important roles in the development of vasculature. Recently, we have found that the mRNA level of RGS5 was oppositely related with tumor metastasis in non-small cell lung cancer (NSCLC). However, the distribution of RGS5 in NSCLC and its significance need further study. We therefore investigated the expression of RGS5 in NSCLC, as well as its relationship with clinicopathologic parameters. Methods: Tumor tissues from 51 NSCLC patients were analyzed and expression of RGS5 in tumor tissues was examined by immunohistochemistry. Chi-square test (or Fisher's exact test), Breslow test and multivariate Cox regression model were performed for statistical analysis. Results: RGS5 were highly expressed in 47% (24/51) of NSCLC specimens. Expression of RGS5 was associated with tumor cell differentiation in NSCLC and low expression of RGS5 was strongly associated with cancer vasculature invasion and lymph node metastasis in NSCLC. Patients with high RGS5 expression in NSCLC had a prolonged progression free survival (15.0 months (95% CI: 6.1-23.9) vs. 6.0 months (95% CI: 1.3-10.7), P = 0.030). Conclusion: RGS5 might be involved in cancer differentiation and metastasis in NSCLC. And it might be a candidate prognostic marker for PFS in NSCLC. J. Surg. Oncol. 2012; 105: 420-424. (C) 2011 Wiley Periodicals, Inc.