S100A6 promotes the proliferation and migration of cervical cancer cells via the PI3K/Akt signaling pathway

Oncol Lett. 2018 Apr;15(4):5685-5693. doi: 10.3892/ol.2018.8018. Epub 2018 Feb 9.

Abstract

Cervical cancer is the second most common gynecological cancer worldwide and remains one of the leading causes of cancer-associated mortality among women. S100A6 has been reported to be associated with the development of many types of cancer. The aim of the present study was to investigate the effect of S100A6 on the proliferation, apoptosis and migration of cervical cancer cells and its underlying molecular mechanisms. Quantative polymerase chain reaction (qPCR) was used to detect the basic mRNA level of S100A6 in HeLa, SiHa and CaSki cells. Western blot analysis was used to detect the protein level of S100A6, epithelial cadherin, neuronal cadherin, phosphorylated protein kinase B (p-Akt), t-Akt, p-glycogen synthase kinase 3β (GSK3β), t-GSK3β and β-catenin. Semi-qPCR was used to detect the mRNA level of Snail, Twist and Vimentin. MTT and Hoechst staining assays were used to detect the proliferation and apoptosis of cells, and wound healing and Transwell assays were used to detect the migration of cells. The results of the present study demonstrate that the levels of S100A6 were decreased in HeLa cells compared with in SiHa and CaSki cells. Overexpression of S100A6 in HeLa and CaSki cells promoted the proliferative and migratory ability, and had no significant effect on cellular apoptosis. Whereas the knockdown of S100A6 in SiHa and CaSki cells inhibited the proliferative and migratory ability, it had no significant effect on apoptosis. The overexpression of S100A6 in HeLa cells increased the levels of neuronal (N)-cadherin, vimentin, Snail and Twist. Conversely, knockdown of S100A6 in SiHa cells decreased the levels of N-cadherin, vimentin, Snail and Twist and increased the levels of epithelial (E)-cadherin. Furthermore, overexpression of S100A6 in HeLa cells activated the phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt) signaling pathway, and treatment with the PI3K inhibitor LY294002 partially repressed S100A6-enhanced proliferation and migration of cervical cancer cells. These results indicate that S100A6 facilitates the malignant potential of cervical cancer cells, particularly metastatic ability and epithelial-mesenchymal transition, which is mediated by activating the PI3K/Akt signaling pathway.

Keywords: S100A6; cervical cancer; epithelial-mesenchymal transition; migration; phosphoinositide 3-kinase/protein kinase B signaling pathway; proliferation.