Kiss-1/GPR54 Protein Expression in Breast Cancer

Background: Numerous studies have shown that the Kiss-1 gene countervails the metastatic aptitude of several cancer cell lines and solid-tumor neoplasias. However, there still remains ambiguity regarding its role in breast cancer and literature has arisen asserting that Kiss-1 expression may be linked to an aggressive phenotype and malignant progression. Herein, we investigated the protein expression of Kiss-1 and its receptor GPR54 in breast cancer tissues compared to non-cancerous mammary tissues. Materials and Methods: Paraffin-fixed cancer tissues from 43 women with resected breast adenocarcinomas and 11 specimens derived from women suffering from fibrocystic disease, serving as controls, were immunostained with Kiss- 1 and GPR54 antibodies. Results: Kiss-1 and GPR54 protein expression levels were significantly higher in breast cancer compared to fibrocystic tissues (p<0.05). No significant correlation was established between Kiss-1 or GRP54 expression and tumor grade, tumor size, lymph node positivity, histological type or ER status. Kiss-1 expression significantly and positively correlated with GPR54 expression in both breast cancer and fibrocystic disease specimens. Conclusion: Kiss-1/GPR54 expression was found to be significantly higher in breast cancer compared to non- malignant mammary tissues.