Silencing of polo-like kinase 2 increases cell proliferation and decreases apoptosis in SGC-7901 gastric cancer cells

Liu,Li  Ying; Wang,Wei; Zhao,Ling  Yu; Guo,Bo; Yang,Juan; Zhao,Xiao  Ge; Song,Tu  Sheng; Huang,Chen; Xu,Ji  Ru

doi:10.3892/mmr.2014.3077

Silencing of polo-like kinase 2 increases cell proliferation and decreases apoptosis in SGC-7901 gastric cancer cells

Authors:
- Li Ying Liu
- Wei Wang
- Ling Yu Zhao
- Bo Guo
- Juan Yang
- Xiao Ge Zhao
- Tu Sheng Song
- Chen Huang
- Ji Ru Xu
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Affiliations: Center Laboratory of Biomedical Research, Key Laboratory of Environment and Genes Related to Diseases of Chinese Ministry of Education, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi 710061, P.R. China, Department of Orthopaedic Surgery, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi 710004, P.R. China, Department of Genetics and Molecular Biology, Molecular Bacteriology Laboratory, Key Laboratory of Environment and Genes Related to Diseases of Chinese Ministry of Education, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi 710061, P.R. China, Department of Immunology and Pathogenic Biology, Molecular Bacteriology Laboratory, Key Laboratory of Environment and Genes Related to Diseases of Chinese Ministry of Education, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi 710061, P.R. China
Published online on: December 11, 2014 https://doi.org/10.3892/mmr.2014.3077
Pages: 3033-3038

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Abstract

Polo‑like kinase 2 (PLK2) is a serine/threonine protein kinase, which has vital roles during mitosis and the centrosome cycle. In acute myeloblastic leukemia and hepatocarcinogenesis, PLK2 acts as a tumor suppressor; however, the function of PLK2 in gastric cancer remains to be elucidated. In the present study, PLK2 was overexpressed in gastric cancer tissues and three types of gastric cancer cells, SGC‑7901, MKN‑45 and BGC‑823. Transfection of SGC‑7901 gastric cancer cells with small interfering (si)RNA against PLK2 exerted no effect on the ratio of cells at different stages of the cell cycle compared with that of the untransfected and control siRNA‑transfected cells. In addition, silencing of PLK2 significantly enhanced the growth of SGC‑7901 cells through inhibiting apoptosis. Furthermore, apoptosis‑associated genes Bax and caspase 3 were found to be downregulated at the protein level. In conclusion, these results suggested that PLK2 may act as a tumor suppressor in gastric cancer, therefore indicating its therapeutic potential.

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