Expression Profile of Epithelial Protein Lost in Neoplasm-Alpha (EPLIN-α) in Human Pulmonary Cancer and Its Impact on SKMES-1 Cells in vitro

Yinan Liu, Andrew J. Sanders, Lijian Zhang, Wen G. Jiang

Cardiff University-Peking University School of Oncology Joint Institute, Cardiff, UK.

DOI: 10.4236/jct.2012.324058                

Abstract

Epithelial Protein Lost in Neoplasm (EPLIN) is a cytoskeletal associated protein implicated in regulating actin dynamoics and cellular motility and whose expression is frequently downregulated in a number of human cancers. The current study examined the expression levels of EPLIN-α in a pulmonary cancer cohort and its association with clinical pathological factors using quantitative polymerase chain reaction. Additionally, EPLIN-α was over-expressed in the SKMES-1 pulmonary cancer cell line through transfection with a plasmid containing the expression sequence for EPLIN-α. The role of EPLIN-α was subsequently examined using a variety of in vitro functional assays. Decreased levels of EPLIN-α were seen in cancerous tissues compared to normal background tissue. Lower levels of EPLIN-α were also associated with higher TNM stage and nodal involvement. In vitro over-expression of EPLIN-α inhibited SKMES-1 growth rates (p = 0.05 vs. plasmid control) and motility (p = 0.002 vs. plasmid control), though did not have any significant effects on cell-matrix adhesion or cell invasion. Taken together, the current study indicates that lower levels of EPLIN-α may be associated with poorer prognosis and more advanced pulmonary cancer, where this molecule appears to play a suppressive role on cell growth and migration.

Keywords

EPLIN-α; Pulmonary Cancer; Cell Migration; ECIS

Conflicts of Interest

The authors declare no conflicts of interest.

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