Proteomic analysis of proteome and histone post-translational modifications in heat shock protein 90 inhibition-mediated bladder cancer therapeutics

Qingdi Quentin Li,Kai H Hammerich,Piyush K Agarwal,Zheng Zhang,Jane B Trepel,Thomas Sanford,Jian-Jiang Hao,L Spencer Krane,Len Neckers

doi:10.1038/s41598-017-00143-6

Abstract

Heat shock protein 90 (HSP90) inhibition is an attractive strategy for cancer treatment. Several HSP90 inhibitors have shown promising effects in clinical oncology trials. However, little is known about HSP90 inhibition-mediated bladder cancer therapy. Here, we report a quantitative proteomic study that evaluates alterations in protein expression and histone post-translational modifications (PTMs) in bladder carcinoma in response to HSP90 inhibition. We show that 5 HSP90 inhibitors (AUY922, ganetespib, SNX2112, AT13387, and CUDC305) potently inhibited the proliferation of bladder cancer 5637 cells in a dose- and time-dependent manner. Our proteomic study quantified 518 twofold up-regulated and 811 twofold down-regulated proteins common to both AUY922 and ganetespib treatment. Bioinformatic analyses revealed that those differentially expressed proteins were involved in multiple cellular processes and enzyme-regulated signaling pathways, including chromatin modifications and cell death-associated pathways. Furthermore, quantitative proteome studies identified 14 types of PTMs with 93 marks on the core histones, including 34 novel histone marks of butyrylation, citrullination, 2-hydroxyisobutyrylation, methylation, O-GlcNAcylation, propionylation, and succinylation in AUY922- and ganetespib-treated 5637 cells. Together, this study outlines the association between proteomic changes and histone PTMs in response to HSP90 inhibitor treatment in bladder carcinoma cells, and thus intensifies the understanding of HSP90 inhibition-mediated bladder cancer therapeutics.

Highlights

Bladder cancer is the second most common genitourinary malignancy and the fourth most commonly diagnosed cancer in males in the United States[1]
The half-maximal inhibitory concentration (IC50) values of the 5 heat shock protein 90 (HSP90) inhibitors at 72 h ranged 0.64 to 200 nM in 5637 cells. These results indicate that these HSP90 inhibitors potently inhibit cell proliferation and induce cell toxicity in bladder cancer 5637 cells
HSP90 inhibitors have been evaluated on multiple regimens in different types of tumors, there is no HSP90 inhibitor currently in clinical trial for urinary bladder cancer

Summary

Introduction

Bladder cancer is the second most common genitourinary malignancy and the fourth most commonly diagnosed cancer in males in the United States[1]. Health care costs, which are significant for patients diagnosed with bladder cancer, are estimated to be $4 billion per year in the United States alone From both clinical and economic perspectives, better treatment strategies are needed for these patients. Inhibition of HSP90 has resulted in significant antitumor effects in multiple cancer animal models[13] It has even been demonstrated as a clinical relevant biomarker in urothelial carcinoma[14]. Among the HSP90 inhibitors, AUY922 (luminespib)[20, 21], ganetespib (STA9090)[22, 23], SNX211224, 25, AT13387 (onalespib)[26], and CUDC30527, 28 are novel, non-geldanamycin-derivative HSP90 inhibitors that have shown significant antitumor activity in a wide range of cancer cell lines, primary tumor cells, and animal cancer models[6, 7, 29]. This study expands our understanding of the role of HSP90 in bladder cancer and significantly furthers our mechanistic understanding of HSP90 inhibitor-mediated bladder cancer therapy

Methods

Results

Conclusion