SCARA3 mRNA is overexpressed in ovarian carcinoma compared to breast carcinoma effusions

Scavenger receptor class A, member 3 (SCARA3) was previously found to be overexpressed in ovarian/primary peritoneal carcinoma (OC/PPC) compared with breast carcinoma effusions by global gene expression analysis. The present study aimed to validate this finding applying quantitative PCR and analyzing the association between SCARA3 expression and clinicopathologic parameters in a large OC cohort. SCARA3 messenger RNA (mRNA) expression was analyzed in 127 effusions (103 ovarian/peritoneal/fallopian tube carcinomas, 9 breast carcinomas, 15 malignant mesotheliomas [MM]), and 30 solid primary OCs. The association between OC SCARA3 levels and clinicopathologic parameters was investigated. SCARA3 mRNA was expressed in all effusions, irrespective of tumor type. However, transcript levels were significantly higher in OC compared with breast carcinoma (P < .001) and MM (P = .011) effusions. Primary OCs and effusions had comparable expression levels. Higher SCARA3 expression was found in disease recurrence postchemotherapy compared with primary diagnosis prechemotherapy OC effusions (P = .001), and this difference was significant for treatment with both platinum agents (P = .006) and paclitaxel (P = .002). SCARA3 levels in effusions and primary carcinomas were unrelated to patient age, tumor grade, FIGO stage, residual tumor volume after surgery, response to chemotherapy, or survival (P > .05 for all). In conclusion, SCARA3 mRNA by quantitative PCR is highly expressed in OC and may aid in differentiating this tumor from other cancers, particularly breast carcinoma, in effusions. The consistently high SCARA3 levels in both primary carcinomas and metastatic cells in effusions, and its up-regulation along disease progression from diagnosis to recurrence, suggest a role in ovarian cancer biology.