PMID- 20956938 OWN - NLM STAT- MEDLINE DCOM- 20110422 LR - 20220316 IS - 1476-5594 (Electronic) IS - 0950-9232 (Print) IS - 0950-9232 (Linking) VI - 30 IP - 5 DP - 2011 Feb 3 TI - Dasatinib sensitizes KRAS mutant colorectal tumors to cetuximab. PG - 561-74 LID - 10.1038/onc.2010.430 [doi] AB - KRAS mutation is a predictive biomarker for resistance to cetuximab (Erbitux) in metastatic colorectal cancer (mCRC). This study sought to determine if KRAS mutant CRC lines could be sensitized to cetuximab using dasatinib (BMS-354825, Sprycel), a potent, orally bioavailable inhibitor of several tyrosine kinases, including the Src family kinases (SFKs). We analyzed 16 CRC lines for: (1) KRAS mutation status, (2) dependence on mutant KRAS signaling and (3) expression level of epidermal growth factor receptor (EGFR) and SFKs. From these analyses, we selected three KRAS mutant (LS180, LoVo and HCT116) cell lines and two KRAS wild-type cell lines (SW48 and CaCo2). In vitro, using poly-D-lysine/laminin plates, KRAS mutant cell lines were resistant to cetuximab, whereas KRAS wild-type lines showed sensitivity to cetuximab. Treatment with cetuximab and dasatinib showed a greater antiproliferative effect on KRAS mutant lines when compared with either agent alone in vitro and in vivo. To investigate potential mechanisms for this antiproliferative response in the combinatorial therapy, we performed Human Phospho-Kinase Antibody Array analysis, measuring the relative phosphorylation levels of 39 intracellular proteins in untreated, cetuximab, dasatinib or the combinatorial treatment in the KRAS mutant lines LS180, LoVo and HCT116 cells. The results of this experiment showed a decrease in a broad spectrum of kinases centered on the beta-catenin pathway, the mitogen-activated protein kinase (MAPK) pathway, AKT/mammalian target of rapamycin (mTOR) pathway and the family of signal transducers and activators of transcription (STATs) when compared with the untreated control or monotherapy treatments. Next, we analyzed tumor growth with cetuximab, dasatinib or their combination in vivo. KRAS mutant xenografts showed resistance to cetuximab therapy, whereas KRAS wild type demonstrated an antitumor response when treated with cetuximab. KRAS mutant tumors exhibited minimal response to dasatinib monotherapy. However, as in vitro, KRAS mutant lines exhibited a response to the combination of cetuximab and dasatinib. Combinatorial treatment of KRAS mutant xenografts resulted in decreased cell proliferation, as measured by Ki67, and higher rates of apoptosis, as measured by TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling). The data presented in this study indicate that dasatinib can sensitize KRAS mutant CRC tumors to cetuximab and may do so by altering the activity of several key signaling pathways. Furthermore, these results suggest that signaling via EGFR and SFKs may be necessary for cell proliferation and survival of KRAS mutant CRC tumors. These data strengthen the rationale for clinical trials combining cetuximab and dasatinib in the KRAS mutant CRC genetic setting. FAU - Dunn, E F AU - Dunn EF AD - Department of Human Oncology, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA. FAU - Iida, M AU - Iida M FAU - Myers, R A AU - Myers RA FAU - Campbell, D A AU - Campbell DA FAU - Hintz, K A AU - Hintz KA FAU - Armstrong, E A AU - Armstrong EA FAU - Li, C AU - Li C FAU - Wheeler, D L AU - Wheeler DL LA - eng GR - UL1 RR025011-01/RR/NCRR NIH HHS/United States GR - P30 CA014520/CA/NCI NIH HHS/United States GR - CA009614-17/CA/NCI NIH HHS/United States GR - UL1 RR025011/RR/NCRR NIH HHS/United States GR - P30CA014520/CA/NCI NIH HHS/United States GR - T32 CA009614-19/CA/NCI NIH HHS/United States GR - T32 CA009614/CA/NCI NIH HHS/United States GR - P30 CA014520-35/CA/NCI NIH HHS/United States GR - 1UL1RR025011/RR/NCRR NIH HHS/United States PT - Journal Article PT - Research Support, N.I.H., Extramural PT - Research Support, Non-U.S. Gov't DEP - 20101018 PL - England TA - Oncogene JT - Oncogene JID - 8711562 RN - 0 (Antibodies, Monoclonal) RN - 0 (Antibodies, Monoclonal, Humanized) RN - 0 (Antineoplastic Agents) RN - 0 (KRAS protein, human) RN - 0 (Protein Kinase Inhibitors) RN - 0 (Proto-Oncogene Proteins) RN - 0 (Pyrimidines) RN - 0 (Thiazoles) RN - EC 2.7.10.1 (ErbB Receptors) RN - EC 2.7.10.2 (src-Family Kinases) RN - EC 3.6.5.2 (Proto-Oncogene Proteins p21(ras)) RN - EC 3.6.5.2 (ras Proteins) RN - PQX0D8J21J (Cetuximab) RN - RBZ1571X5H (Dasatinib) SB - IM CIN - Nat Rev Clin Oncol. 2011 Apr;8(4):193. PMID: 21451492 CIN - Small GTPases. 2012 Jan-Mar;3(1):34-9. PMID: 22714415 MH - Animals MH - Antibodies, Monoclonal/administration & dosage/*pharmacology MH - Antibodies, Monoclonal, Humanized MH - Antineoplastic Agents/administration & dosage/pharmacology MH - Antineoplastic Combined Chemotherapy Protocols/*therapeutic use MH - Apoptosis/drug effects MH - Caco-2 Cells MH - Cell Line, Tumor MH - Cell Proliferation/drug effects MH - Cetuximab MH - Colorectal Neoplasms/*drug therapy/genetics/pathology MH - Dasatinib MH - Drug Resistance, Neoplasm/drug effects/genetics MH - Drug Synergism MH - ErbB Receptors/metabolism MH - HCT116 Cells MH - Humans MH - Immunoblotting MH - Male MH - Mice MH - Mice, Nude MH - Mutation MH - Protein Kinase Inhibitors/administration & dosage/pharmacology MH - Proto-Oncogene Proteins/*genetics/metabolism MH - Proto-Oncogene Proteins p21(ras) MH - Pyrimidines/administration & dosage/*pharmacology MH - RNA Interference MH - Thiazoles/administration & dosage/*pharmacology MH - Xenograft Model Antitumor Assays MH - ras Proteins/*genetics/metabolism MH - src-Family Kinases/metabolism PMC - PMC3025039 MID - NIHMS228291 COIS- Conflict of interest DLW holds a sponsored research agreement with Bristol-Myer Squibb. EDAT- 2010/10/20 06:00 MHDA- 2011/04/26 06:00 PMCR- 2011/08/01 CRDT- 2010/10/20 06:00 PHST- 2010/10/20 06:00 [entrez] PHST- 2010/10/20 06:00 [pubmed] PHST- 2011/04/26 06:00 [medline] PHST- 2011/08/01 00:00 [pmc-release] AID - onc2010430 [pii] AID - 10.1038/onc.2010.430 [doi] PST - ppublish SO - Oncogene. 2011 Feb 3;30(5):561-74. doi: 10.1038/onc.2010.430. Epub 2010 Oct 18.