title: Targeted inhibition of the extracellular signal-regulated kinase kinase pathway with AZD6244 (ARRY-142886) in the treatment of hepatocellular carcinoma.
abstract: Hepatocellular carcinoma (HCC) is a common malignancy in Asia and Africa. We previously reported that overexpression of extracellular signal-regulated kinase (ERK) kinase 1/2 (MEK1/2) and ERK1/2 was detected in HCC, and that their activation was required for liver cancer cell proliferation and survival. In the present study, we determined the efficacy of a specific MEK1/2 inhibitor AZD6244 (ARRAY-142886) in treatment of HCC. Treatment of primary HCC cells with AZD6244 led to growth inhibition, elevation of the cleavage of caspase-3 and caspase-7, and cleaved poly(ADP)ribose polymerase, but inhibition of ERK1/2 and p90RSK phosphorylation. Studying the protein expression profile of seven HCC xenografts revealed that their growth rate was positively correlated with the levels of phosphorylated MEK. AZD6244, when given p.o. to mice bearing these xenografts, resulted in a dose-dependent inhibition of tumor growth. AZD6244-induced growth suppression was associated with inactivation of ERK1/2 and p90RSK, and up-regulation of activated caspase-3 and caspase-7, and cleaved poly(ADP)ribose polymerase. Our data suggest that the MEK-ERK pathway plays an important role in the growth and survival of liver cancer cells and that the HCC xenograft models are excellent tools for screening preclinical drugs. Targeted inhibition of the MEK-ERK pathway with AZD6244 may represent an alternative approach for the treatment of this disease.
authors.affiliation: Laboratory of Molecular Endocrinology, Division of Cellular and Molecular Research, National Cancer Centre of Singapore, Singapore 169610, Singapore. cmrhth@nccs.com.sg
authors.forename: Hung
authors.initials: H
authors.lastname: Huynh
authors.forename: Khee Chee
authors.initials: KC
authors.lastname: Soo
authors.forename: Pierce K H
authors.initials: PK
authors.lastname: Chow
authors.forename: Evelyn
authors.initials: E
authors.lastname: Tran
mesh_terms: D000818:Animals; D001562:Benzimidazoles / Q000494:pharmacology* / Q000627:therapeutic use*; D006528:Carcinoma, Hepatocellular / Q000188:drug therapy* / Q000201:enzymology / Q000378:metabolism; D053148:Caspase 3 / Q000378:metabolism; D053179:Caspase 7 / Q000378:metabolism; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D048049:Extracellular Signal-Regulated MAP Kinases / Q000037:antagonists & inhibitors* / Q000378:metabolism; D006801:Humans; D008113:Liver Neoplasms / Q000188:drug therapy* / Q000201:enzymology / Q000378:metabolism; D048728:MAP Kinase Kinase Kinase 1 / Q000037:antagonists & inhibitors / Q000378:metabolism; D051379:Mice; D016513:Mice, SCID; D010766:Phosphorylation / Q000187:drug effects; D011065:Poly(ADP-ribose) Polymerases / Q000378:metabolism; D047428:Protein Kinase Inhibitors / Q000494:pharmacology* / Q000627:therapeutic use*; D048493:Proto-Oncogene Proteins B-raf / Q000378:metabolism; D038744:Ribosomal Protein S6 Kinases, 90-kDa / Q000037:antagonists & inhibitors / Q000378:metabolism; D013997:Time Factors; D047368:Tumor Burden / Q000187:drug effects; D023041:Xenograft Model Antitumor Assays
chemical_list: C517975:AZD 6244; D001562:Benzimidazoles; D047428:Protein Kinase Inhibitors; D011065:Poly(ADP-ribose) Polymerases; D048493:Proto-Oncogene Proteins B-raf; D038744:Ribosomal Protein S6 Kinases, 90-kDa; D048049:Extracellular Signal-Regulated MAP Kinases; D048728:MAP Kinase Kinase Kinase 1; D053148:Caspase 3; D053179:Caspase 7