Cigarette Smoke Condensate Triggers Transcriptional Regulation of bcl-xl Gene in Human Breast Epithelial Cells

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Cigarette smoke condensate has been shown to transform human breast epithelial cells by upregulating the anti-apoptotic gene bcl-xl, thereby impeding the apoptotic pathway and allowing the accumulation of DNA damage that can lead to cell transformation and carcinogenesis. Researchers have now identified the mechanism by which cigarette smoke condensate upregulates bcl-xl gene expression in MCF10A cells, revealing a potential target for chemotherapeutic intervention of cigarette smoke-induced breast carcinogenesis.

Key Takeaways:

  • Cigarette smoke condensate transforms human breast epithelial cells by upregulating the anti-apoptotic gene bcl-xl (S.K. Connors et al., 2009).
  • Upregulation of bcl-xl may impede the apoptotic pathway and allow the accumulation of DNA damage leading to cell transformation and carcinogenesis (S.K. Connors et al., 2009).
  • Researchers identified CCAAT/enhancer-binding protein (C/EBPbeta) as a transcription factor that regulates bcl-xl gene expression in MCF10A cells in response to cigarette smoke condensate treatment (S.K. Connors et al., 2009).
  • C/EBPbeta binding to a C/EBP-binding site on the pBcl-xLP was confirmed by gel-shift, super-shift, and chromatin immunoprecipitation analysis (S.K. Connors et al., 2009).
  • Overexpression of C/EBPbeta-LAP2 stimulated pBcl-xLP activity and Bcl-xL protein levels, mimicking the conditions of cigarette smoke condensate treatment (S.K. Connors et al., 2009).
  • C/EBPbeta may be a potential target for chemotherapeutic intervention of cigarette smoke-induced breast carcinogenesis (S.K. Connors et al., 2009).
  • The study suggests that C/EBPbeta-mediated transcriptional regulation of bcl-xl gene expression plays a crucial role in cigarette smoke-induced breast carcinogenesis.

Statistics:

  • The study was published in the journal Oncogene in 2009.
  • The study used the MCF10A human breast epithelial cell line, which was transformed by cigarette smoke condensate.
  • The study identified the bcl-xl gene as a potential therapeutic target for cigarette smoke-induced breast carcinogenesis.
  • The study suggests that C/EBPbeta binding to the pBcl-xLP is essential for cigarette smoke condensate-mediated bcl-xl gene expression.

Sources:

  • S.K. Connors et al. (2009). C/EBPbeta-mediated transcriptional regulation of bcl-xl gene expression in human breast epithelial cells in response to cigarette smoke condensate. Oncogene, 28(6), 921-932.
  • Nature Publishing Group. (n.d.). Oncogene. Retrieved from
  • University of Florida. (n.d.). Department of Anatomy and Cell Biology. Retrieved from