BAG2 promotes tumorigenesis through enhancing mutant p53 protein levels and function

  1. Xuetian Yue
  2. Yuhan Zhao
  3. Juan Liu
  4. Cen Zhang
  5. Haiyang Yu
  6. Jiabei Wang
  7. Tongsen Zheng
  8. Lianxin Liu
  9. Jun Li
  10. Zhaohui Feng
  11. Wenwei Hu  Is a corresponding author
  1. Rutgers University Newark Campus, United States
  2. Harbin Medical University, China

Abstract

Tumor suppressor p53 is the most frequently mutated gene in tumors. Many mutant p53 (mutp53) proteins promote tumorigenesis through the gain-of-function (GOF) mechanism. Mutp53 proteins often accumulate to high levels in tumors, which is critical for mutp53 GOF. Its underlying mechanism is poorly understood. Here, we found that BAG2, a protein of Bcl-2 associated athanogene (BAG) family, promotes mutp53 accumulation and GOF in tumors. Mechanically, BAG2 binds to mutp53 and translocates to the nucleus to inhibit the MDM2-mutp53 interaction, and MDM2-mediated ubiquitination and degradation of mutp53. Thus, BAG2 promotes mutp53 accumulation and GOF in tumor growth, metastasis and chemoresistance. BAG2 is frequently overexpressed in tumors. BAG2 overexpression is associated with poor prognosis in patients and mutp53 accumulation in tumors. These findings revealed a novel and important mechanism for mutp53 accumulation and GOF in tumors, and also uncovered an important role of BAG2 in tumorigenesis through promoting mutp53 accumulation and GOF.

Article and author information

Author details

  1. Xuetian Yue

    Rutgers University Newark Campus, New Brunswick, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Yuhan Zhao

    Rutgers University Newark Campus, New Brunswick, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Juan Liu

    Rutgers University Newark Campus, New Brunswick, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Cen Zhang

    Rutgers University Newark Campus, New Brunswick, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Haiyang Yu

    Rutgers University Newark Campus, New Brunswick, United States
    Competing interests
    The authors declare that no competing interests exist.
  6. Jiabei Wang

    Rutgers University Newark Campus, New Brunswick, United States
    Competing interests
    The authors declare that no competing interests exist.
  7. Tongsen Zheng

    Rutgers University Newark Campus, New Brunswick, United States
    Competing interests
    The authors declare that no competing interests exist.
  8. Lianxin Liu

    Key laboratory of hepatosplenic surgery, Harbin Medical University, Harbin, China
    Competing interests
    The authors declare that no competing interests exist.
  9. Jun Li

    Rutgers University Newark Campus, New Brunswick, United States
    Competing interests
    The authors declare that no competing interests exist.
  10. Zhaohui Feng

    Rutgers University Newark Campus, New Brunswick, United States
    Competing interests
    The authors declare that no competing interests exist.
  11. Wenwei Hu

    Rutgers University Newark Campus, New Brunswick, United States
    For correspondence
    wh221@cinj.rutgers.edu
    Competing interests
    The authors declare that no competing interests exist.

Ethics

Animal experimentation: This study was performed in strict accordance with the recommendations in the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health. All of the animals were handled according to approved institutional animal care and use committee (IACUC) protocol (#I13-028) of Rutgers University.

Copyright

© 2015, Yue et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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  1. Xuetian Yue
  2. Yuhan Zhao
  3. Juan Liu
  4. Cen Zhang
  5. Haiyang Yu
  6. Jiabei Wang
  7. Tongsen Zheng
  8. Lianxin Liu
  9. Jun Li
  10. Zhaohui Feng
  11. Wenwei Hu
(2015)
BAG2 promotes tumorigenesis through enhancing mutant p53 protein levels and function
eLife 4:e08401.
https://doi.org/10.7554/eLife.08401

Share this article

https://doi.org/10.7554/eLife.08401

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