title: Novel Ras pathway inhibitor induces apoptosis and growth inhibition of K-ras-mutated cancer cells in vitro and in vivo.
abstract: MT477 is a novel quinoline with potential activity in Ras-mutated cancers. In this study, MT477 preferentially inhibited the proliferation of K-ras-mutated human pulmonary (A549) and pancreatic (MiaPaCa-2) adenocarcinoma cell lines, compared with a non-Ras-mutated human lung squamous carcinoma cell line (H226) and normal human lung fibroblasts. MT477 treatment induced apoptosis in A549 cells and was associated with caspase-3 activation. MT477 also induced sub-G1 cell-cycle arrest in A549 cells. Although we found that MT477 partially inhibited protein kinase C (PKC), it inhibited Ras directly followed in time by inhibition of 2 Ras downstream molecules, Erk1/2 and Ral. MT477 also caused a reorganization of the actin cytoskeleton and formation of filopodias in A549 cells; this event may lead to decreased migration and invasion of tumor cells. In a xenograft mouse model, A549 tumor growth was inhibited significantly by MT477 at a dose of 1 mg/kg (P < 0.05 vs vehicle control). Taken together, these results support the conclusion that MT477 acts as a direct Ras inhibitor. This quinoline, therefore, could potentially be active in Ras-mutated cancers and could be developed extensively as an anticancer molecule with this in mind.
authors.affiliation: Division of Hematology, Oncology and Transplantation, Department of Medicine, University of Minnesota, Minneapolis, Minn. 55455, USA.
authors.forename: Piotr
authors.initials: P
authors.lastname: Jasinski
authors.forename: Pawel
authors.initials: P
authors.lastname: Zwolak
authors.forename: Kaoru
authors.initials: K
authors.lastname: Terai
authors.forename: Arkadiusz Z
authors.initials: AZ
authors.lastname: Dudek
mesh_terms: D008841:Actin Cytoskeleton / Q000187:drug effects; D000230:Adenocarcinoma / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D053148:Caspase 3 / Q000378:metabolism; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D005347:Fibroblasts / Q000166:cytology; D006801:Humans; D008175:Lung Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D008297:Male; D051379:Mice; D008819:Mice, Nude; D009154:Mutation; D015689:Oncogene Protein p21(ras) / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D010190:Pancreatic Neoplasms / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology; D011493:Protein Kinase C / Q000037:antagonists & inhibitors / Q000378:metabolism; D011804:Quinolines / Q000494:pharmacology*; D015398:Signal Transduction / Q000187:drug effects*; D023041:Xenograft Model Antitumor Assays
chemical_list: D011804:Quinolines; C530123:dimethyl 5,6-dihydro-7-methoxy-5,5-dimethyl-6-(2-(2,5-dioxopyrrolidin-1-yl)acetyl)-1H-1-(4,5-dimethoxycarbonyl-1,3-dithiolo-2-spiro)thiopyrano(2,3-c)quinoline-2,3-dicarboxylate; D011493:Protein Kinase C; D053148:Caspase 3; D015689:Oncogene Protein p21(ras)