title: STK31 is a cell-cycle regulated protein that contributes to the tumorigenicity of epithelial cancer cells.
abstract: Serine/threonine kinase 31 (STK31) is one of the novel cancer/testis antigens for which its biological functions remain largely unclear. Here, we demonstrate that STK31 is overexpressed in many human colorectal cancer cell lines and tissues. STK31 co-localizes with pericentrin in the centrosomal region throughout all phases of the cell cycle. Interestingly, when cells undergo mitosis, STK31 also localizes to the centromeres, central spindle, and midbody. This localization behavior is similar to that of chromosomal passenger proteins, which are known to be the important players of the spindle assembly checkpoint. The expression of STK31 is cell cycle-dependent through the regulation of a putative D-box near its C-terminal region. Ectopically-expressed STK31-GFP increases cell migration and invasive ability without altering the proliferation rate of cancer cells, whereas the knockdown expression of endogenous STK31 by lentivirus-derived shRNA results in microtubule assembly defects that prolong the duration of mitosis and lead to apoptosis. Taken together, our results suggest that the aberrant expression of STK31 contributes to tumorigenicity in somatic cancer cells. STK31 might therefore act as a potential therapeutic target in human somatic cancers.
authors.affiliation: Department of Medical Laboratory Science BioTechnology, College of Medicine, National Cheng Kung University, Tainan, Taiwan; Department of Obstetrics and Gynecology, National Cheng-Kung University Hospital, Tainan, Taiwan.
authors.forename: Pao-Lin
authors.initials: PL
authors.lastname: Kuo
authors.affiliation: Department of Medical Laboratory Science BioTechnology, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
authors.forename: Yung-Ling
authors.initials: YL
authors.lastname: Huang
authors.affiliation: Department of Medical Laboratory Science BioTechnology, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
authors.forename: Christine Chin-Jung
authors.initials: CC
authors.lastname: Hsieh
authors.affiliation: Department of Surgery, National Cheng-Kung University Hospital, Tainan, Taiwan.
authors.forename: Jenq-Chang
authors.initials: JC
authors.lastname: Lee
authors.affiliation: Department of Surgery, National Cheng-Kung University Hospital, Tainan, Taiwan.
authors.forename: Bo-Wen
authors.initials: BW
authors.lastname: Lin
authors.affiliation: Institute of Bioinformatics and Biosignal Transduction, College of Bioscience and Biotechnology, National Cheng Kung University, Tainan, Taiwan; Center for Infectious Disease and Signal Transduction Research, National Cheng Kung University, Tainan, Taiwan; Institute for Cancer Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan.
authors.forename: Liang-Yi
authors.initials: LY
authors.lastname: Hung
mesh_terms: D063646:Carcinogenesis; D002453:Cell Cycle; D045744:Cell Line, Tumor; D002465:Cell Movement; D018385:Centrosome / Q000378:metabolism; D015179:Colorectal Neoplasms / Q000473:pathology; D015972:Gene Expression Regulation, Neoplastic; D055785:Gene Knockdown Techniques; D006801:Humans; D018386:Kinetochores / Q000378:metabolism; D008870:Microtubules / Q000378:metabolism; D008938:Mitosis; D009361:Neoplasm Invasiveness; D009375:Neoplasms, Glandular and Epithelial / Q000473:pathology*; D017346:Protein Serine-Threonine Kinases / Q000172:deficiency / Q000235:genetics / Q000378:metabolism*; D021381:Protein Transport; D034741:RNA, Small Interfering / Q000235:genetics
chemical_list: D034741:RNA, Small Interfering; D017346:Protein Serine-Threonine Kinases; C000592903:STK31 protein, human