title: Cell cycle-dependent expression of p42.3 promotes mitotic progression in malignant transformed cells.
abstract: In an earlier study, we cloned the p42.3 gene and showed that its expression was specific to tumors in a number of tumor cell lines and primary tumor tissues. However, the biological role and function of this gene remains largely unknown. In this study, p42.3 expression was found to be cell cycle-dependent at both the mRNA and protein levels in several human tumor cell lines. Typically, abundant expression was detected at G1 and M phases compared with S and G2 phases. Expression peaked at early G1 phase then decreased drastically at late G1, S, and G2. Furthermore, transfection of the p42.3 gene into NIH3T3 cells promoted malignant transformation, accompanied by accelerated mitotic progression and altered chromosome segregation. It was also observed that Cyclin B1 was upregulated and Cdc2-Tyr15 was downregulated following p42.3 overexpression in NIH3T3 cells. Combined, these results indicate that p42.3 as a cell cycle-regulated gene contributes to promoting cell cycle progression through disruption of mitotic regulation, and may play important roles in malignant transformation.
authors.affiliation: Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Laboratory of Molecular Oncology, Peking University Cancer Hospital & Institute, Beijing, China.
authors.forename: Linlin
authors.initials: L
authors.lastname: Mao
authors.forename: Wei
authors.initials: W
authors.lastname: Sun
authors.forename: Wenmei
authors.initials: W
authors.lastname: Li
authors.forename: Jiantao
authors.initials: J
authors.lastname: Cui
authors.forename: Jingyu
authors.initials: J
authors.lastname: Zhang
authors.forename: Rui
authors.initials: R
authors.lastname: Xing
authors.forename: Youyong
authors.initials: Y
authors.lastname: Lu
mesh_terms: D000818:Animals; D017209:Apoptosis; D015153:Blotting, Western; D002453:Cell Cycle / Q000502:physiology*; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism*; D049109:Cell Proliferation; D002471:Cell Transformation, Neoplastic / Q000378:metabolism / Q000473:pathology*; D005434:Flow Cytometry; D005455:Fluorescent Antibody Technique; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007124:Immunoenzyme Techniques; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D008856:Microscopy, Fluorescence; D008938:Mitosis / Q000502:physiology*; D041681:NIH 3T3 Cells; D009687:Nuclear Proteins; D012333:RNA, Messenger / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013274:Stomach Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D014407:Tumor Cells, Cultured
chemical_list: D018797:Cell Cycle Proteins; D009687:Nuclear Proteins; D012333:RNA, Messenger; C000607889:SAPCD2 protein, human