Leukocyte-associated immunoglobulin-like receptor-1 expressed in epithelial ovarian cancer cells and involved in cell proliferation and invasion

Previous studies have shown that leukocyte-associated immunoglobulin-like receptor-1 (LAIR-1) is expressed on most types of hamatopoietic cells and negatively regulate immune response, but the roles of LAIR-1 in tumor of the non-hematopoietic lineage have not been determined. Despite advances in therapy of epithelial ovarian cancer (EOC), many questions relating to EOC pathogenesis remain unanswered. The aim of this study was to investigate the clinical significance of LAIR-1 expression in EOC and explore the possible association between LAIR-1 and cancer. In this study, a tissue microarray containing 78 ovarian cancer cases was stained following a standard immunohistochemical protocol for LAIR-1 and the correlation of LAIR-1 expression with clinicopathologic features was assessed. LAIR-1 was detected to express in tumor cells of ovarian cancer tissues (73.1%) and EOC cell lines COC1 and HO8910, not in normal ovarian tissues. In addition, LAIR-1 expression correlates significantly with tumor grade (p = 0.004). Furthermore, down-regulation of LAIR-1 in HO8910 cells increased cell proliferation, colony formation and cell invasion. These data suggest that LAIR-1 has a relevant impact on EOC progression and may be helpful for a better understanding of molecular pathogenesis of cancer.