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Heat shock protein 90 inhibition abrogates hepatocellular cancer growth through cdc2-mediated G2/M cell cycle arrest and apoptosis.

ABSTRACT: 17-(demethoxy), 17-allylamino geldanamycin (17-AAG) suppresses growth in some cancers by inhibiting Heat shock protein 90 (Hsp90). We examined the effects of 17-AAG-mediated Hsp90 inhibition on human hepatocellular carcinoma (HCC) growth in vitro and in vivo.Human HCC cell lines, Hep3B and HuH7, were exposed to 17-AAG and cell viabilities and apoptosis were determined. Cell cycle profiles were analyzed and the G(2)/M cell cycle checkpoint proteins cdc2 and cyclin B1 were examined. Studies were performed to determine whether 17-AAG-mediated cdc2 decrease was due to altered gene expression, transcription, or protein degradation. The effects of 17-AAG on Hep3B and HuH7 xenograft growth in athymic nude mice were also examined.Hep3B and HuH7 treated with 17-AAG versus untreated controls showed decreased cell viability and increased apoptosis. Cells treated with 17-AAG also showed an increased fraction in G(2)/M phase and an associated decrease in cdc2 through protein degradation rather than through other mechanisms. Hsp90 inhibition by 17-AAG also decreased HCC xenograft growth in association with decreased cdc2 expression.17-AAG-mediated inhibition of Hsp90 abrogates human HCC cell growth in vitro and in vivo through cdc2 decrease, which in turn induces G(2)/M cell cycle arrest and apoptosis. Hsp90 is a mediator of HCC growth and survival and its inhibition may serve as a potential treatment.

SUBMITTER: Watanabe G

PROVIDER: S-EPMC4122215 | biostudies-literature | 2009 Aug

REPOSITORIES: biostudies-literature

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Heat shock protein 90 inhibition abrogates hepatocellular cancer growth through cdc2-mediated G2/M cell cycle arrest and apoptosis.

Watanabe Go G Behrns Kevin E KE Kim Jae-Sung JS Kim Robin D RD

Cancer chemotherapy and pharmacology 20081212 3

<h4>Purpose</h4>17-(demethoxy), 17-allylamino geldanamycin (17-AAG) suppresses growth in some cancers by inhibiting Heat shock protein 90 (Hsp90). We examined the effects of 17-AAG-mediated Hsp90 inhibition on human hepatocellular carcinoma (HCC) growth in vitro and in vivo.<h4>Methods</h4>Human HCC cell lines, Hep3B and HuH7, were exposed to 17-AAG and cell viabilities and apoptosis were determined. Cell cycle profiles were analyzed and the G(2)/M cell cycle checkpoint proteins cdc2 and cyclin ...[more]

PMID: 19082595

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Dataset Information

Heat shock protein 90 inhibition abrogates hepatocellular cancer growth through cdc2-mediated G2/M cell cycle arrest and apoptosis.

Publications

Heat shock protein 90 inhibition abrogates hepatocellular cancer growth through cdc2-mediated G2/M cell cycle arrest and apoptosis.

Similar Datasets

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