NAC1, a BTB/POZ protein overexpressed in uterine sarcomas.

BACKGROUND The purpose of this study was to investigate the role of Nucleus accumbens-associated 1 (NAC1) in the development of uterine sarcomas. MATERIALS AND METHODS NAC1 expression and localization in the normal myometrium, benign leiomyoma, and uterine sarcoma were assessed with immunohistochemistry. NAC1-specific siRNA was used to inactivate NAC1 for in vitro biological assays. RESULTS Almost all cases of uterine sarcoma were found to overexpress NAC1. Expression of NAC1 was significantly higher in uterine sarcomas than in benign leiomyomas (p<0.0001). NAC1 gene knockdown inhibited cell growth and induced apoptosis in SKN, a leiomyosarcoma cell line, and in OMC-9, an endometrial stromal sarcoma cell line, both of which overexpress NAC1. CONCLUSION Uterine sarcomas with NAC1 overexpression are clinically the most aggressive, chemoresistant, and radioresistant tumors. Therefore, detection of NAC1 overexpression in uterine sarcomas may identify patients who will benefit from NAC1-targeted therapy.