Objective: This study examined MASPIN expression in human ovarian cancer, and explored the association between MASPIN and prognosis in patients with advanced stage disease treated with first-line cisplatin, carboplatin and/or paclitaxel.
Methods: Frozen primary tumors were obtained from 68 women with previously untreated, advanced stage epithelial ovarian cancer who participated in a specimen banking protocol and a phase III treatment trial conducted by the Gynecologic Oncology Group. Immunoblot analysis was performed in lysates prepared from these tumor specimens to quantify the relative expression of MASPIN/beta-actin.
Results: MASPIN was expressed at detected levels in 49 (72%) cases with relative expression ranging from 0.02 to 7.7 (median = 0.2), and was not detected in 19 (28%) of the primary tumors tested. Non-detectable levels of this class II tumor suppressor gene product and inhibitor of angiogenesis were associated with suboptimally-debulked disease (P = 0.034) but not with patient age, FIGO stage, tumor grade, or histologic subtype. After adjusting for prognostic variables for disease progression or death, non-detectable MASPIN expression predicted an increased risk of disease progression (hazard ratio [HR] = 1.89; 95% confidence interval [CI]: 1.04-3.45; P = 0.038) and death (HR = 1.99; 95% CI: 1.07-3.69; P = 0.030).
Conclusions: In advanced stage epithelial ovarian cancer, non-detectable MASPIN appears to be associated with suboptimally-debulked disease and be an independent predictor of an increased risk of progression and death. Further studies are needed to validate these exploratory findings, determine the molecular mechanism controlling MASPIN expression as well as down-regulation and loss in ovarian cancer, and determine if MASPIN can prevent progression of this disease.