Expression of αV-associated integrin β subunits in epithelial ovarian cancer andits relation to prognosis in patients treated with platinum-based regimens

The aim of the study was to investigate the relationships between the expression of alphav, beta1, beta3, beta5, and beta6, integrin subunits and clinical parameters in ovarian cancers. Ovarian surface epithelium (OSE) from five donors and tumour samples from 39 patients with an epithelial ovarian cancer ( 39 primary tumours and 21 associated peritoneal metastases) were analysed using immunohistochemistry on paraffin-embedded or frozen tissue sections. The alphav and beta5 integrin subunits were always present in normal OSE and in tumours. beta1 and beta3 subunit expression was significantly less frequent in grade 3 than in grade 1 - 2 tumours. The proportion of stage IV tumours expressing beta3 was significantly lower as compared to other stages. The beta6 subunit was undetectable in OSE but was expressed in about 40% of primary tumours. For all integrin, there was a strong relationship between the expression in primary tumours and in associated peritoneal metastases. Survival analyses restricted to patients receiving platinum-based chemotherapy did not reveal any relationship between integrin subunit expression and 3-year survival rate, in this limited series of patients. In conclusion, the expression of the various beta integrin subunits was differentially altered in ovarian carcinoma, evocative of complementary roles of av integrins during tumour development.