title: In vitro and in vivo synergy of MCP compounds with mitogen-activated protein kinase pathway- and microtubule-targeting inhibitors.
abstract: An important clinical task is to coherently integrate the use of protein-targeted drugs into preexisting therapeutic regimens, with the goal of improving treatment efficacy. Constitutive activation of Ras-dependent signaling is important in many tumors, and agents that inhibit this pathway might be useful in numerous therapeutic combinations. The MCP compounds were identified as inhibitors of Ras-Raf interactions and previously shown to inhibit multiple Ras-dependent transformation phenotypes when used as monoagents in cell culture analyses. In this study, we investigate the ability of the MCP110 compound to synergistically enhance the activity of other therapeutic agents. In both a defined K-Ras-transformed fibroblast model and in human tumor cell lines with mutationally activated Ras, MCP110 selectively synergizes with other agents targeting the mitogen-activated protein kinase pathway, and with multiple agents (paclitaxel, docetaxel, and vincristine) targeting the microtubule network. The synergistic activity of MCP110 and paclitaxel was further established by experiments showing that in Kaposi's sarcoma oncogenically transformed cell lines, cellular models for tumors treated with taxanes in the clinic and in which Raf-dependent signaling plays an important role, MCP110 synergizes with paclitaxel and limit growth. Finally, in vivo testing indicate that MCP110 is bioavailable, inhibits the growth of LXFA 629 lung and SW620 colon carcinoma cells in xenograft models, and again strongly synergizes with paclitaxel. Together, these findings indicate that MCP compounds have potential to be effective in combination with other anticancer agents.
authors.affiliation: Fox Chase Cancer Center, 333 Cottman Avenue, Philadelphia, PA 19111, USA.
authors.forename: Natalia
authors.initials: N
authors.lastname: Skobeleva
authors.forename: Sanjay
authors.initials: S
authors.lastname: Menon
authors.forename: Lutz
authors.initials: L
authors.lastname: Weber
authors.forename: Erica A
authors.initials: EA
authors.lastname: Golemis
authors.forename: Vladimir
authors.initials: V
authors.lastname: Khazak
mesh_terms: D016475:3T3 Cells / Q000187:drug effects; D000818:Animals; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D002289:Carcinoma, Non-Small-Cell Lung / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology; D002453:Cell Cycle / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D002471:Cell Transformation, Neoplastic / Q000187:drug effects; D003110:Colonic Neoplasms / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology; D000077143:Docetaxel; D004357:Drug Synergism; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D006801:Humans; D066298:In Vitro Techniques; D008175:Lung Neoplasms / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology; D008297:Male; D051379:Mice; D008819:Mice, Nude; D016513:Mice, SCID; D008870:Microtubules / Q000187:drug effects*; D020928:Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors* / Q000378:metabolism; D017239:Paclitaxel / Q000008:administration & dosage; D019908:Proto-Oncogene Proteins c-raf / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D016283:Proto-Oncogene Proteins p21(ras) / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects*; D043823:Taxoids / Q000008:administration & dosage; D015533:Transcriptional Activation / Q000187:drug effects; D014407:Tumor Cells, Cultured / Q000187:drug effects; D014750:Vincristine / Q000008:administration & dosage; D023041:Xenograft Model Antitumor Assays
chemical_list: D004791:Enzyme Inhibitors; D043823:Taxoids; D000077143:Docetaxel; D014750:Vincristine; D019908:Proto-Oncogene Proteins c-raf; D020928:Mitogen-Activated Protein Kinases; D016283:Proto-Oncogene Proteins p21(ras); D017239:Paclitaxel