Dataset Information

Ganetespib targets multiple levels of the receptor tyrosine kinase signaling cascade and preferentially inhibits ErbB2-overexpressing breast cancer cells.

ABSTRACT: Although ErbB2-targeted therapeutics have significantly improved ErbB2+ breast cancer patient outcomes, therapeutic resistance remains a significant challenge. Therefore, the development of novel ErbB2-targeting strategies is necessary. Importantly, ErbB2 is a sensitive client protein of heat shock protein 90 (HSP90), which regulates client protein folding, maturation, and stabilization. HSP90 inhibition provides an alternative therapeutic strategy for ErbB2-targeted degradation. In particular, ganetespib, a novel HSP90 inhibitor, is a promising agent for ErbB2+ cancers. Nevertheless, the anti-cancer efficacy and clinical application of ganetespib for ErbB2+ breast cancer is largely unknown. In our study, we examined the anti-cancer effects of ganetespib on ErbB2+ BT474 and SKBR3 breast cancer cells, and isogenic paired cancer cell lines with lentivirus-mediated ErbB2 overexpression. Ganetespib potently inhibited cell proliferation, cell cycle progression, survival, and activation/phosphorylation of ErbB2 and key downstream effectors in ErbB2+ breast cancer cells. Moreover, ganetespib decreased the total protein levels of HSP90 client proteins and reduced ErbB2 protein half-life. ErbB2-overexpressing cancer cells were also more sensitive to ganetespib-mediated growth inhibition than parental cells. Ganetespib also strikingly potentiated the inhibitory effects of lapatinib in BT474 and SKBR3 cells. Ultimately, our results support the application of ganetespib-mediated HSP90 inhibition as a promising therapeutic strategy for ErbB2+ breast cancer.

SUBMITTER: Lee H

PROVIDER: S-EPMC5931511 | biostudies-literature | 2018 May

REPOSITORIES: biostudies-literature

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Ganetespib targets multiple levels of the receptor tyrosine kinase signaling cascade and preferentially inhibits ErbB2-overexpressing breast cancer cells.

Lee Harry H Saini Nipun N Howard Erin W EW Parris Amanda B AB Ma Zhikun Z Zhao Qingxia Q Zhao Ming M Liu Bolin B Edgerton Susan M SM Thor Ann D AD Yang Xiaohe X

Scientific reports 20180501 1

Although ErbB2-targeted therapeutics have significantly improved ErbB2<sup>+</sup> breast cancer patient outcomes, therapeutic resistance remains a significant challenge. Therefore, the development of novel ErbB2-targeting strategies is necessary. Importantly, ErbB2 is a sensitive client protein of heat shock protein 90 (HSP90), which regulates client protein folding, maturation, and stabilization. HSP90 inhibition provides an alternative therapeutic strategy for ErbB2-targeted degradation. In p ...[more]

PMID: 29717218

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Dataset Information

Ganetespib targets multiple levels of the receptor tyrosine kinase signaling cascade and preferentially inhibits ErbB2-overexpressing breast cancer cells.

Publications

Ganetespib targets multiple levels of the receptor tyrosine kinase signaling cascade and preferentially inhibits ErbB2-overexpressing breast cancer cells.

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