Tumor Biology

, Volume 37, Issue 1, pp 1279–1287 | Cite as

Loss of TIM50 suppresses proliferation and induces apoptosis in breast cancer

  • Shui-Ping Gao
  • He-Fen Sun
  • Hong-Lin Jiang
  • Liang-Dong Li
  • Xin Hu
  • Xiao-En Xu
  • Wei Jin
Original Article

Abstract

TIM50 is an essential component of TIM23 complex and involved in protein translocating into the inner mitochondrial membrane. Here, we found that TIM50 was increased in breast cancer cells by SILAC. However, its biological functions and molecular mechanisms in breast cancer are poorly understood. To gain insight into the functions of TIM50 in breast cancer, we constructed two stably transfected cell lines and examined TIM50 expression in tissue samples. Our data showed that TIM50 expression was increased in breast cancer. The stable suppression of TIM50 expression through lentivirus-mediated shRNA was shown to inhibit the abilities of cancer cell proliferation and induce apoptosis. What is more, depletion of TIM50 could decrease mitochondrial membrane potential, which may be associated with cell viability. Taken together, our findings reveal a new role for TIM50 in regulating cell proliferation and apoptosis through decreasing mitochondrial membrane potential in breast cancer cell and suggest that TIM50 might be a potential target for controlling breast cancer progression.

Keywords

TIM50 Cell viability Breast cancer Mitochondrial membrane potential 

Abbreviation

TIM50

Translocase of inner mitochondrial membrane 50 homolog

NC

Negative control

MMP

Mitochondria membrane potential

SILAC

Stable isotope labeling with amino acids in cell culture

MS

Mass spectrum

Notes

Acknowledgments

This work was supported by the grants from National Natural Science Foundation of China (81472669 and 81272923).

Conflicts of interest

None

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Copyright information

© International Society of Oncology and BioMarkers (ISOBM) 2015

Authors and Affiliations

  • Shui-Ping Gao
    • 1
    • 2
  • He-Fen Sun
    • 1
    • 2
  • Hong-Lin Jiang
    • 1
    • 2
  • Liang-Dong Li
    • 1
    • 2
  • Xin Hu
    • 1
    • 2
  • Xiao-En Xu
    • 1
    • 2
  • Wei Jin
    • 1
    • 2
  1. 1.Department of Breast Surgery, Key Laboratory of Breast Cancer in Shanghai, Collaborative Innovation Center of Cancer MedicineFudan University Shanghai Cancer CenterShanghaiChina
  2. 2.Department of Oncology, Shanghai Medical CollegeFudan UniversityShanghaiChina

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