101. Targeting p130Cas- and microtubule-dependent MYC regulation sensitizes pancreatic cancer to ERK MAPK inhibition
- Author
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Kevin S. Kapner, William C. Hahn, Nanyun Tang, Hongwei H. Yin, Kaisheng Chen, Michelle Kassner, Bjoern Papke, Thomas S. K. Gilbert, A. Cole Edwards, J. Nathaniel Diehl, Sehrish Javaid, Tala O. Khatib, Devon R. Blake, Kajal R. Grover, James M. McFarland, Katherine H. Walsh, Tikvah K. Hayes, Manpreet Kalkat, Katherine M. Nowak, Channing J. Der, G. Aaron Hobbs, Olga Tanaseichuk, Adele Waters, Lee M. Graves, Antje Schaefer, Adrienne D. Cox, Clint A. Stalnecker, Linda Z. Penn, Craig M. Goodwin, Anna Barkovskaya, Andrew J. Aguirre, Priya S. Hibshman, Jennifer E. Klomp, Yingyao Zhou, Laura E. Herring, Rita Sulahian, and Runying Yang
- Subjects
0301 basic medicine ,MAPK/ERK pathway ,Small interfering RNA ,Transcription, Genetic ,Pyridines ,pancreatic cancer ,Apoptosis ,MYC ,medicine.disease_cause ,Microtubules ,0302 clinical medicine ,Tubulin ,Acetamides ,Biology (General) ,Extracellular Signal-Regulated MAP Kinases ,p130Cas ,Chemistry ,Calpain ,Drug Synergism ,Gene Expression Regulation, Neoplastic ,Organoids ,ERK ,src-Family Kinases ,Phosphorylation ,KRAS ,Proto-oncogene tyrosine-protein kinase Src ,Half-Life ,QH301-705.5 ,Morpholines ,Down-Regulation ,General Biochemistry, Genetics and Molecular Biology ,Article ,Proto-Oncogene Proteins c-myc ,Proto-Oncogene Proteins p21(ras) ,03 medical and health sciences ,Pancreatic cancer ,Cell Line, Tumor ,medicine ,Humans ,Protein Kinase Inhibitors ,Cell Proliferation ,TUBB3 ,medicine.disease ,Xenograft Model Antitumor Assays ,Pancreatic Neoplasms ,030104 developmental biology ,Crk-Associated Substrate Protein ,BCAR1 ,Mutation ,Cancer research ,030217 neurology & neurosurgery - Abstract
SUMMARY To identify therapeutic targets for KRAS mutant pancreatic cancer, we conduct a druggable genome small interfering RNA (siRNA) screen and determine that suppression of BCAR1 sensitizes pancreatic cancer cells to ERK inhibition. Integrative analysis of genome-scale CRISPR-Cas9 screens also identify BCAR1 as a top synthetic lethal interactor with mutant KRAS. BCAR1 encodes the SRC substrate p130Cas. We determine that SRC-inhibitor-mediated suppression of p130Cas phosphorylation impairs MYC transcription through a DOCK1-RAC1-β-catenin-dependent mechanism. Additionally, genetic suppression of TUBB3, encoding the βIII-tubulin subunit of microtubules, or pharmacological inhibition of microtubule function decreases levels of MYC protein in a calpain-dependent manner and potently sensitizes pancreatic cancer cells to ERK inhibition. Accordingly, the combination of a dual SRC/tubulin inhibitor with an ERK inhibitor cooperates to reduce MYC protein and synergistically suppress the growth of KRAS mutant pancreatic cancer. Thus, we demonstrate that mechanistically diverse combinations with ERK inhibition suppress MYC to impair pancreatic cancer proliferation., Graphical Abstract, In brief Using integrated analysis of genome-scale screens, Waters et al. identify BCAR1 and TUBB3, encoding p130Cas and βIII-tubulin, as two pancreatic cancer vulnerabilities that, when inhibited, sensitize KRAS mutant PDAC cells to ERK inhibition. Mechanistically, inhibition of p130Cas, βIII-tubulin, and ERK converges on and drives MYC loss to inhibit pancreatic cancer growth.
- Published
- 2020