Expression of herpesvirus-associated ubiquitin specific protease(HAUSP) in breast carcinoma and its clinical significance / 中国癌症杂志

ABSTRACT

Background and purpose: Herpesvirus-associated ubiquitin-specific protease (HAUSP) is a new deubiquitinating enzyme that was recently discovered. It has been demonstrated that HAUSP could deubiquitinate p53 both in vitro and in vivo. These results suggested that HAUSP might act as a tumor suppressor through the stabilization of p53 protein. The aim of this study was to investigate the expression of HAUSP in breast carcinoma, and its association with p53 protein as well as their relationship to prognosis. Methods: The expression of HAUSP mRNA was detected by real-time PCR. HAUSP protein and p53 protein were detected by immunohistochemistry with EnVision system in breast carcinoma tissues and noncancerous tissues. The relationship between their expressions and clinical pathological parameters were analyzed. Results: The expression of HAUSP mRNA was significantly lower in breast cancer tissue than noncancerous tissue (1.85±0.04 vs. 2.74±0.03, P<0.01). The positive rates of HAUSP protein were significantly lower in breast cancer tissue in noncancerous tissue (59.4% vs. 75.0%, P<0.01), and expression of HAUSP protein had no significant correlation with the clinical pathological parameters. There was no significant correlation between HAUSP and p53 protein (P>0.05). The expression of HAUSP mRNA was positively associated with that of HAUSP protein (P<0.01). There was no significant correlation between HAUSP and p53 protein. DFS of patients with both HAUSP positive and p53 negative was significant higher than the controls (P<0.01). Conclusion: Down-regulation of HAUSP protein and HAUSP mRNA in breast carcinoma indicated that HAUSP gene might correlated to tumor carcinogenesis. In addition, the simultaneous evaluation of both HAUSP expression and p53 expression status may be helpful to evaluate the prognosis of breast cancer patients.