Upregulation of the cycline kinase subunit CKS2 increases cell proliferation rate in gastric cancer.
OBJECTIVE
CKS2 was identified as an upregulated gene in gastric cancer via our DNA microarray. This study was to verify the upregulation of CKS2 in many gastric cancer patients and to examine the CKS2-mediated cellular response.


METHODS
CKS2 upregulation was analyzed using reverse transcriptase PCR, real-time PCR, and immunohistochemical and clinicopathological analyses. GFP-CKS2 or CKS2-siRNA was used to analyze the cellular localization and proliferation.


RESULTS
The strong upregulation of mRNA and protein levels of CKS2 was identified. In CKS2-overexpressing cells, tumor suppressor p53 and p21(cip1) were downregulated and cell growth was increased. In contrast, CKS2-siRNA-transfected cells showed an increased tumor suppressor expression and decreased cell growth.


CONCLUSIONS
We showed that CKS2 was significantly upregulated in gastric cancers and a high level of CKS2 was highly correlated with histologic tumor differentiation and pathological grade of the tumor size, lymph node, and metastasis stage. We suggest that the cell cycle regulator CKS2 might be deeply involved in gastric cancer progression.
Kang
Min Ah
MA
Stem Cell Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, Republic of Korea.
Kim
Jong-Tae
JT
Kim
Joo Heon
JH
Kim
Soo-Young
SY
Kim
Young Ho
YH
Yeom
Young Il
YI
Lee
Younghee
Y
Lee
Hee Gu
HG
D015153:Blotting, Western; D042846:CDC2-CDC28 Kinases; D002352:Carrier Proteins / Q000235:genetics* / Q000378:metabolism; D018797:Cell Cycle Proteins / Q000235:genetics* / Q000378:metabolism; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D018613:Microscopy, Confocal; D008875:Middle Aged; D011494:Protein Kinases / Q000235:genetics* / Q000378:metabolism; D034741:RNA, Small Interfering / Q000235:genetics; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013274:Stomach Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D014158:Transcription, Genetic; D014162:Transfection; D016159:Tumor Suppressor Protein p53 / Q000235:genetics / Q000378:metabolism; D015854:Up-Regulation
D002352:Carrier Proteins; D018797:Cell Cycle Proteins; D034741:RNA, Small Interfering; D011993:Recombinant Fusion Proteins; D016159:Tumor Suppressor Protein p53; D049452:Green Fluorescent Proteins; D011494:Protein Kinases; D042846:CDC2-CDC28 Kinases; C083689:CKS2 protein, human