SKA3 Up-regulation Promotes Lung Adenocarcinoma Growth and is a Predictor of Poor Prognosis

The objective of this research is to investigate the expression and function of SKA3 in lung adenocarcinoma.

The mRNA expression level of SKA3 in lung adenocarcinoma and its association with clinic-pathological factors were analyzed using data obtained from the TCGA database. Small interfering RNA (siRNA) for SKA3 (si-SKA3) was used to down-regulate SKA3 in A549 cells. pcDNA3.1- SKA3 was used to overexpress SKA3 in A549 cells. The proliferation ability of A549 cells was determined via MTT assay and colony formation assay. A wound healing assay was performed to examine the migration ability of A549 cells. The protein expression of p-MEK, MEK, p-ERK and ERK were determined by western blot.

We found that SKA3 is up-regulated in lung adenocarcinoma compared to the normal lung tissues. Kaplan-Meier analysis showed that high SKA3 expression is markedly associated with poor prognosis in lung adenocarcinoma patients. SKA3 expression is significantly correlated with age, gender, pathologic-stage, pathologic-N and pathologic-M. Moreover, depleting SKA3 obviously inhibited A549 cell proliferation and migration in vitro, while overexpression of SKA3 notably increased A549 cell proliferation and migration. Western blot analysis showed that the protein expression ratio of p-MEK/MEK and p-ERK/ERK decreased noticeably after depleting SKA3.

SKA3 expression was enhanced and associated with poor prognosis in lung adenocarcinoma patients, and it might play a facilitating role in cell growth and motility by regulating the MAPK signaling pathway.