Calpain-2 expression is associated with response to platinum based chemotherapy, progression-free and overall survival in ovarian cancer

Ovarian cancer is routinely treated with surgery and platinum‐based chemotherapy. Resistance is a major obstacle in the efficacy of this chemotherapy regimen and the ability to identify those patients at risk of developing resistance is of considerable clinical importance. The expression of calpain‐1, calpain‐2 and calpastatin were determined using standard immunohistochemistry on a tissue microarray of 154 primary ovarian carcinomas from patients subsequently treated with platinum‐based adjuvant chemotherapy. High levels of calpain‐2 expression was significantly associated with platinum resistant tumours (P = 0.031). Furthermore, high expression of calpain‐2 was significantly associated with progression‐free (P = 0.049) and overall survival (P = 0.006) in this cohort. The association between calpain‐2 expression and overall survival remained significant in multivariate analysis accounting for tumour grade, stage, optimal debulking and platinum sensitivity (hazard ratio = 2.174; 95% confidence interval = 1.144–4.130; P = 0.018). The results suggest that determining calpain‐2 expression in ovarian carcinomas may allow prognostic stratification of patients treated with surgery and platinum‐based chemotherapy. The findings of this study warrant validation in a larger clinical cohort.