Computational master-regulator search reveals mTOR and PI3K pathways responsible for low sensitivity of NCI-H292 and A427 lung cancer cell lines to cytotoxic action of p53 activator Nutlin-3

BMC Med Genomics. 2018 Feb 13;11(Suppl 1):12. doi: 10.1186/s12920-018-0330-5.

Abstract

Background: Small molecule Nutlin-3 reactivates p53 in cancer cells by interacting with the complex between p53 and its repressor Mdm-2 and causing an increase in cancer cell apoptosis. Therefore, Nutlin-3 has potent anticancer properties. Clinical and experimental studies of Nutlin-3 showed that some cancer cells may lose sensitivity to this compound. Here we analyze possible mechanisms for insensitivity of cancer cells to Nutlin-3.

Methods: We applied upstream analysis approach implemented in geneXplain platform ( genexplain.com ) using TRANSFAC® database of transcription factors and their binding sites in genome and using TRANSPATH® database of signal transduction network with associated software such as Match™ and Composite Module Analyst (CMA).

Results: Using genome-wide gene expression profiling we compared several lung cancer cell lines and showed that expression programs executed in Nutlin-3 insensitive cell lines significantly differ from that of Nutlin-3 sensitive cell lines. Using artificial intelligence approach embed in CMA software, we identified a set of transcription factors cooperatively binding to the promoters of genes up-regulated in the Nutlin-3 insensitive cell lines. Graph analysis of signal transduction network upstream of these transcription factors allowed us to identify potential master-regulators responsible for maintaining such low sensitivity to Nutlin-3 with the most promising candidate mTOR, which acts in the context of activated PI3K pathway. These finding were validated experimentally using an array of chemical inhibitors.

Conclusions: We showed that the Nutlin-3 insensitive cell lines are actually highly sensitive to the dual PI3K/mTOR inhibitor NVP-BEZ235, while no responding to either PI3K -specific LY294002 nor Bcl-XL specific 2,3-DCPE compounds.

Keywords: Lung cancer cell lines; Nutlin-3; Sensitivity to anticancer drugs; TRANSFAC; Transcription factors; p53.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Apoptosis
  • Cell Proliferation
  • Drug Resistance, Neoplasm*
  • Humans
  • Imidazoles / pharmacology*
  • Lung Neoplasms / drug therapy
  • Lung Neoplasms / metabolism
  • Lung Neoplasms / pathology*
  • Phosphatidylinositol 3-Kinases / genetics
  • Phosphatidylinositol 3-Kinases / metabolism*
  • Piperazines / pharmacology*
  • Protein Kinase Inhibitors / pharmacology*
  • Signal Transduction
  • TOR Serine-Threonine Kinases / genetics
  • TOR Serine-Threonine Kinases / metabolism*
  • Tumor Cells, Cultured
  • Tumor Suppressor Protein p53 / genetics
  • Tumor Suppressor Protein p53 / metabolism*

Substances

  • Imidazoles
  • Piperazines
  • Protein Kinase Inhibitors
  • TP53 protein, human
  • Tumor Suppressor Protein p53
  • nutlin 3
  • Phosphatidylinositol 3-Kinases
  • MTOR protein, human
  • TOR Serine-Threonine Kinases