1. Academic Validation
  2. Temporal proteomics reveal specific cell cycle oncoprotein downregulation by p97/VCP inhibition

Temporal proteomics reveal specific cell cycle oncoprotein downregulation by p97/VCP inhibition

  • Cell Chem Biol. 2022 Mar 17;29(3):517-529.e5. doi: 10.1016/j.chembiol.2021.11.005.
Feng Wang 1 Shan Li 2 Nadia Houerbi 2 Tsui-Fen Chou 3
Affiliations

Affiliations

  • 1 Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA. Electronic address: fengwang@caltech.edu.
  • 2 Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA.
  • 3 Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA; Proteome Exploration Laboratory, Beckman Institute, California Institute of Technology, Pasadena, CA 91125, USA. Electronic address: tfchou@caltech.edu.
Abstract

Targeting protein quality control (PQC) pathways using Proteasome or p97/VCP inhibition can effectively treat blood tumors. However, in solid tumors, only p97/VCP inhibitors are effective. To probe this difference in efficacy, we tracked HCT116 colon Cancer cells using temporal proteomics to define the cellular and molecular responses to Proteasome and p97 inhibition. Proteins involved in general PQC pathways were similarly upregulated by both treatments, suggesting that the proteotoxic stress caused by inhibitors does not explain the differential therapeutic effectiveness. Unexpectedly, proteins specifically dysregulated by two p97 inhibitors are involved in cell cycle control. Indeed, eleven cell cycle proteins were downregulated by p97 inhibition but not by Proteasome inhibition. Western blot analysis validated the degradation of cyclin D1 and Securin, which depends on Proteasome but not on p97. Differing regulation of cell cycle proteins by p97 and the Proteasome may, therefore, explain the therapeutic efficacy of p97 inhibitors in colon Cancer.

Keywords

CB-5083; E2F1; NMS-873; UPCDC-30245; anticancer; cell cycle; cyclin D1; p97 inhibitor; proteasome inhibitor; proteomic.

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