Molecular and Cellular Biochemistry

, Volume 428, Issue 1–2, pp 109–118 | Cite as

Gap junction protein connexin43 deregulation contributes to bladder carcinogenesis via targeting MAPK pathway

  • Xiao-lin Ai
  • Qiang Chi
  • Yu Qiu
  • Hong-yang Li
  • Dong-jie Li
  • Jia-xu Wang
  • Zhi-yong Wang


High expression of connexins was found in a variety of cancers, but their role is still controversial. We investigated whether connexin43 (Cx43) contributed to bladder carcinogenesis through MAPK activation. In this study, we found that Cx43 expression was significantly increased in bladder cancer tissues and cell line. Overexpression of Cx43 in bladder cancer 5637 cells increased cell proliferation, promoted cell cycle progression, and inhibited apoptosis. Western blot showed that JNK and ERK pathways were dramatically activated in Cx43-overexpressed cells. Conversely, knockdown of Cx43 inhibited cell proliferation by increasing apoptosis and causing cell cycle arrest, concomitant with inhibition of JNK and ERK signaling. In addition, JNK and ERK pathways were also activated in bladder cancer tissues. In conclusion, abnormal high expression and cytoplasmic localization of Cx43 contributed to bladder cancer. Inhibition of Cx43 activity could be a potential therapeutic strategy for preventing the progression of bladder cancer.


Bladder cancer Connexin43 JNK ERK 



This work was supported by grants from the scientific research youth fund project of affiliated hospital of Chengde medical University.

Compliance with ethical standards

Conflict of interest

The authors have no conflict of interest to disclose.


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Copyright information

© Springer Science+Business Media New York 2017

Authors and Affiliations

  • Xiao-lin Ai
    • 1
  • Qiang Chi
    • 1
  • Yu Qiu
    • 1
  • Hong-yang Li
    • 1
  • Dong-jie Li
    • 1
  • Jia-xu Wang
    • 2
  • Zhi-yong Wang
    • 1
  1. 1.Department of UrologyAffiliated Hospital of Chengde Medical UniversityChengdeChina
  2. 2.Department of PathologyAffiliated Hospital of Chengde Medical UniversityChengdeChina

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