title: Novel small molecule XPO1/CRM1 inhibitors induce nuclear accumulation of TP53, phosphorylated MAPK and apoptosis in human melanoma cells.
abstract: XPO1/CRM1 is a key nuclear exporter protein that mediates translocation of numerous cellular regulatory proteins. We investigated whether XPO1 is a potential therapeutic target in melanoma using novel selective inhibitors of nuclear export (SINE). In vitro effects of SINE on cell growth and apoptosis were measured by MTS assay and flow cytometry [Annexin V/propidium iodide (PI)], respectively in human metastatic melanoma cell lines. Immunoblot analysis was used to measure nuclear localization of key cellular proteins. The in vivo activity of oral SINE was evaluated in NOD/SCID mice bearing A375 or CHL-1 human melanoma xenografts. SINE compounds induced cytostatic and pro-apoptotic effects in both BRAF wild type and mutant (V600E) cell lines at nanomolar concentrations. The cytostatic and pro-apoptotic effects of XPO1 inhibition were associated with nuclear accumulation of TP53, and CDKN1A induction in the A375 cell line with wild type TP53, while pMAPK accumulated in the nucleus regardless of TP53 status. The orally bioavailable KPT-276 and KPT-330 compounds significantly inhibited growth of A375 (p<0.0001) and CHL-1 (p = 0.0087) human melanoma cell lines in vivo at well tolerated doses. Inhibition of XPO1 using SINE represents a potential therapeutic approach for melanoma across cells with diverse molecular phenotypes by promoting growth inhibition and apoptosis.
authors: Department of Internal Medicine, The Ohio State University, Columbus, Ohio, United States of America.
authors: Jennifer
authors: J
authors: Yang
authors: Department of Internal Medicine, The Ohio State University, Columbus, Ohio, United States of America.
authors: Matthew A
authors: MA
authors: Bill
authors: Center for Biostatistics, The Ohio State University, Columbus, Ohio, United States of America.
authors: Gregory S
authors: GS
authors: Young
authors: Department of Veterinary Biosciences, The Ohio State University, Columbus, Ohio, United States of America.
authors: Krista
authors: K
authors: La Perle
authors: Karyopharm Therapeutics, Natick, Massachusetts, United States of America.
authors: Yosef
authors: Y
authors: Landesman
authors: Karyopharm Therapeutics, Natick, Massachusetts, United States of America.
authors: Sharon
authors: S
authors: Shacham
authors: Karyopharm Therapeutics, Natick, Massachusetts, United States of America.
authors: Michael
authors: M
authors: Kauffman
authors: Karyopharm Therapeutics, Natick, Massachusetts, United States of America.
authors: William
authors: W
authors: Senapedis
authors: Karyopharm Therapeutics, Natick, Massachusetts, United States of America.
authors: Trinayan
authors: T
authors: Kashyap
authors: Karyopharm Therapeutics, Natick, Massachusetts, United States of America.
authors: Jean-Richard
authors: JR
authors: Saint-Martin
authors: Department of Internal Medicine, The Ohio State University, Columbus, Ohio, United States of America.
authors: Kari
authors: K
authors: Kendra
authors: Department of Internal Medicine, The Ohio State University, Columbus, Ohio, United States of America.
authors: Gregory B
authors: GB
authors: Lesinski
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000737:chemistry / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D002453:Cell Cycle / Q000187:drug effects; D045744:Cell Line, Tumor; D002467:Cell Nucleus / Q000187:drug effects / Q000378:metabolism; D049109:Cell Proliferation / Q000187:drug effects; D050759:Cyclin-Dependent Kinase Inhibitor p21 / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D028884:Karyopherins / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D008545:Melanoma / Q000188:drug therapy* / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D051379:Mice; D016688:Mice, Inbred NOD; D016513:Mice, SCID; D020928:Mitogen-Activated Protein Kinases / Q000235:genetics / Q000378:metabolism; D010766:Phosphorylation / Q000187:drug effects; D048493:Proto-Oncogene Proteins B-raf / Q000235:genetics / Q000378:metabolism; D018160:Receptors, Cytoplasmic and Nuclear / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction; D012878:Skin Neoplasms / Q000188:drug therapy* / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D054852:Small Molecule Libraries / Q000737:chemistry / Q000494:pharmacology*; D016159:Tumor Suppressor Protein p53 / Q000235:genetics / Q000378:metabolism; D023041:Xenograft Model Antitumor Assays; D000097606:Exportin 1 Protein
chemical_list: D000970:Antineoplastic Agents; D050759:Cyclin-Dependent Kinase Inhibitor p21; D028884:Karyopherins; D020928:Mitogen-Activated Protein Kinases; D048493:Proto-Oncogene Proteins B-raf; D018160:Receptors, Cytoplasmic and Nuclear; D054852:Small Molecule Libraries; D016159:Tumor Suppressor Protein p53; D000097606:Exportin 1 Protein; C493956:CDKN1A protein, human; C495901:TP53 protein, human; C482120:Braf protein, mouse