Co-expression of S100A14 and S100A16 correlates with a poor prognosis in human breast cancer and promotes cancer cell invasion

S100 family proteins have recently been identified as biomarkers in various cancers. Of this protein family, S100A14 and S100A16 are also believed to play an important role in tumor progression. The aim of the present study was to clarify the clinical significance and functional role of these molecules in breast cancer.

Tanaka et al BMC Cancer (2015) 15:53 DOI 10.1186/s12885-015-1059-6 RESEARCH ARTICLE Open Access Co-expression of S100A14 and S100A16 correlates with a poor prognosis in human breast cancer and promotes cancer cell invasion Mizuko Tanaka1, Naoki Ichikawa-Tomikawa1, Namiko Shishito1, Keisuke Nishiura1, Tomiko Miura1, Ayumi Hozumi1, Hideki Chiba1, Sayaka Yoshida2, Tohru Ohtake2 and Takashi Sugino3* Abstract Background: S100 family proteins have recently been identified as biomarkers in various cancers Of this protein family, S100A14 and S100A16 are also believed to play an important role in tumor progression The aim of the present study was to clarify the clinical significance and functional role of these molecules in breast cancer Methods: In a clinical study, an immunohistochemical analysis of S100A14 and S100A16 expression in archival specimens of primary tumors of 167 breast cancer patients was performed The relationship of S100A14 and S100A16 expression to patient survival and clinicopathological variables was statistically analyzed In an experimental study, the subcellular localization and function of these molecules was examined by using the human breast cancer cell lines MCF7 and SK-BR-3, both of which highly express S100A14 and S100A16 proteins Cells transfected with expression vectors and siRNA for these genes were characterized using in vitro assays for cancer invasion and metastasis Results: Immunohistochemical analysis of 167 breast cancer cases showed strong cell membrane staining of S100A14 (53% of cases) and S100A16 (31% of cases) with a significant number of cases with co-expression (p < 0.001) Higher expression levels of these proteins were significantly associated with a younger age (