title: An RNA-seq-based gene expression profiling of radiation-induced tumorigenic mammary epithelial cells.
abstract: Immortality and tumorigenicity are two distinct characteristics of cancers. Immortalization has been suggested to precede tumorigenesis. To understand the molecular mechanisms of tumorigenicity and cancer progression in mammary epithelium, we established a tumorigenic cell model by means of heavy-ion radiation of an immortal cell model, which was created by overexpressing the human telomerase reverse transcriptase (hTERT) in normal human mammary epithelial cells. We examined the expression profile of this tumorigenic cell line (T_hMEC) using the hTERT-overexpressing immortal cell line (I_hMEC) as a control. In-depth RNA-seq data was generated by using the next-generation sequencing (NGS) platform (Life Technologies SOLiD3). We found that house-keeping (HK) and tissue-specific (TS) genes were differentially regulated during the tumorigenic process. HK genes tended to be activated while TS genes tended to be repressed. In addition, the HK genes and TS genes tended to contribute differentially to the variation of gene expression at different RPKM (gene expression in reads per exon kilobase per million mapped sequence reads) levels. Based on transcriptome analysis of the two cell lines, we defined 7053 differentially-expressed genes (DEGs) between immortality and tumorigenicity. Differential expression of 20 manually-selected genes was further validated using qRT-PCR. Our observations may help to further our understanding of cellular mechanism(s) in the transition from immortalization to tumorigenesis.
authors: CAS Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 100029, China.
authors: Lina
authors: L
authors: Ma
authors: Linghu
authors: L
authors: Nie
authors: Jing
authors: J
authors: Liu
authors: Bing
authors: B
authors: Zhang
authors: Shuhui
authors: S
authors: Song
authors: Min
authors: M
authors: Sun
authors: Jin
authors: J
authors: Yang
authors: Yadong
authors: Y
authors: Yang
authors: Xiangdong
authors: X
authors: Fang
authors: Songnian
authors: S
authors: Hu
authors: Yongliang
authors: Y
authors: Zhao
authors: Jun
authors: J
authors: Yu
mesh_terms: D001483:Base Sequence; D001943:Breast Neoplasms / Q000235:genetics*; D002460:Cell Line; D045744:Cell Line, Tumor; D002471:Cell Transformation, Neoplastic / Q000235:genetics*; D004847:Epithelial Cells / Q000166:cytology / Q000378:metabolism; D015870:Gene Expression; D020869:Gene Expression Profiling; D053263:Gene Regulatory Networks; D059014:High-Throughput Nucleotide Sequencing; D006801:Humans; D042361:Mammary Glands, Human / Q000166:cytology* / Q000378:metabolism / Q000473:pathology; D009381:Neoplasms, Radiation-Induced / Q000235:genetics*; D012313:RNA / Q000235:genetics*; D019098:Telomerase / Q000235:genetics
chemical_list: D012313:RNA; C509186:TERT protein, human; D019098:Telomerase