title: MYC pathway is activated in clear cell renal cell carcinoma and essential for proliferation of clear cell renal cell carcinoma cells.
abstract: Clear cell renal cell carcinoma (ccRCC) is the major and aggressive subtype of RCC. Previously, we identified 383 differentially expressed genes by analyzing full-length cDNA libraries of ccRCC and normal kidney tissues. In this study, we applied functional network analysis to the differentially expressed genes for identifying deregulated molecular pathways in ccRCC, and the results indicated that MYC showed a prominent role in the highest scoring network. The upregulation of MYC expression was validated in ccRCC tissues and cell lines. Furthermore, Knockdown of MYC expression by MYC-specific siRNA significantly inhibited the abilities of uncontrolled proliferation, anchorage-independent growth and arrested cell cycle in the G0/G1 phase in ccRCC cells. Moreover, we found that 37 differentially expressed genes were shown to be MYC-target genes, and the upregulation of the MYC-target genes BCL2, CCND1, PCNA, PGK1, and VEGFA were demonstrated. The expression of these MYC-target genes was significantly correlated with the expression of MYC in ccRCC tissues, and knockdown of MYC also suppressed the expression of these MYC-target genes in ccRCC cells. The recruitment of MYC to the promoter regions of BCL2, CCND1, PCNA, PGK1, and VEGFA was shown by Chromatin immunoprecipitation assay. These results suggest that MYC pathway is activated and plays an essential role in the proliferation of ccRCC cells.
authors.affiliation: Institute of Biochemistry and Molecular Biology, College of Medicine, National Taiwan University, Taipei 100, Taiwan, ROC.
authors.forename: Sai-Wen
authors.initials: SW
authors.lastname: Tang
authors.forename: Wen-Hsin
authors.initials: WH
authors.lastname: Chang
authors.forename: Yih-Ching
authors.initials: YC
authors.lastname: Su
authors.forename: Yu-Chi
authors.initials: YC
authors.lastname: Chen
authors.forename: Yen-Han
authors.initials: YH
authors.lastname: Lai
authors.forename: Pei-Tzu
authors.initials: PT
authors.lastname: Wu
authors.forename: Chyong-Ing
authors.initials: CI
authors.lastname: Hsu
authors.forename: Wei-Chou
authors.initials: WC
authors.lastname: Lin
authors.forename: Ming-Kuen
authors.initials: MK
authors.lastname: Lai
authors.forename: Jung-Yaw
authors.initials: JY
authors.lastname: Lin
mesh_terms: D015153:Blotting, Western; D002292:Carcinoma, Renal Cell / Q000235:genetics / Q000378:metabolism / Q000503:physiopathology*; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007150:Immunohistochemistry; D007680:Kidney Neoplasms / Q000235:genetics / Q000378:metabolism / Q000503:physiopathology*; D016271:Proto-Oncogene Proteins c-myc / Q000235:genetics / Q000378:metabolism*; D034622:RNA Interference; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction; D015854:Up-Regulation
chemical_list: D016271:Proto-Oncogene Proteins c-myc