The cytoprotective role of gemcitabine-induced autophagy associated with apoptosis inhibition in triple-negative MDA-MB-231 breast cancer cells

  • Authors:
    • Ming Chen
    • Mengye He
    • Yinjing Song
    • Luoquan Chen
    • Peng Xiao
    • Xiaopeng Wan
    • Feng Dai
    • Peng Shen
  • View Affiliations

  • Published online on: May 6, 2014     https://doi.org/10.3892/ijmm.2014.1772
  • Pages: 276-282
Metrics: Total Views: 0 (Spandidos Publications: | PMC Statistics: )
Total PDF Downloads: 0 (Spandidos Publications: | PMC Statistics: )


Abstract

Triple-negative breast cancer (TNBC), which is estrogen receptor (ER)-negative, progesterone receptor‑negative and is also negative for HER2 expression, remains a great clinical challenge due to its strong resistance to chemotherapy at the late stage of treatment and relatively unfavorable prognosis. Gemcitabine has been approved by the FDA/SFDA for use as a first-line therapeutic drug against advanced or metastatic breast cancer. Therefore, the clarification of the mechanisms underlying gemcitabine-acquired resistance is of particular importance for the optimal management of TNBC. A number of studies have revealed that autophagy, which has been found to protect cancer cells from anti-cancer drug-induced death, may contribute to the development of drug resistance. However, the association between autophagy and gemcitabine treatment in TNBC cells has yet to be defined. Our study clearly demonstrates that gemcitabine is able to induce mTOR-independent autophagy in human triple‑negative MDA-MB-231 breast cancer cells. In addition, we demonstrate that autophagy protects MDA-MB-231 cells from gemcitabine-induced cell growth inhibition and apoptosis, indicating that gemcitabine can activate autophagy to impair the sensitivity of MDA-MB‑231 cells. Furthermore, as shown by our results, the inhibition of gemcitabine-induced autophagy by chloroquine shifts the expression of the p53 protein, Bcl-2 family proteins and the relative Bax/Bcl-xL ratio in favor of promoting apoptosis. These results reveal that the inhibition of apoptosis may be one of the mechanisms of autophagy-induced cytoprotection in gemcitabine-treated MDA-MB-231 cells. The apoptotic and autophagic processes constitute a mutual inhibition system and jointly seal the fate of TNBC cells that are exposed to gemcitabine. Thus, our study suggests that the combination of an autophagic inhibitor and gemcitabine as a therapeutic strategy may represent a promising approach with greater clinical efficacy for patients with TNBC. However, extended preclinical trials are required to further determine the positive effects of the inhibition of autophagy on the efficacy of gemcitabine.
View Figures
View References

Related Articles

Journal Cover

July-2014
Volume 34 Issue 1

Print ISSN: 1107-3756
Online ISSN:1791-244X

Sign up for eToc alerts

Recommend to Library

Copy and paste a formatted citation
x
Spandidos Publications style
Chen M, He M, Song Y, Chen L, Xiao P, Wan X, Dai F and Shen P: The cytoprotective role of gemcitabine-induced autophagy associated with apoptosis inhibition in triple-negative MDA-MB-231 breast cancer cells. Int J Mol Med 34: 276-282, 2014
APA
Chen, M., He, M., Song, Y., Chen, L., Xiao, P., Wan, X. ... Shen, P. (2014). The cytoprotective role of gemcitabine-induced autophagy associated with apoptosis inhibition in triple-negative MDA-MB-231 breast cancer cells. International Journal of Molecular Medicine, 34, 276-282. https://doi.org/10.3892/ijmm.2014.1772
MLA
Chen, M., He, M., Song, Y., Chen, L., Xiao, P., Wan, X., Dai, F., Shen, P."The cytoprotective role of gemcitabine-induced autophagy associated with apoptosis inhibition in triple-negative MDA-MB-231 breast cancer cells". International Journal of Molecular Medicine 34.1 (2014): 276-282.
Chicago
Chen, M., He, M., Song, Y., Chen, L., Xiao, P., Wan, X., Dai, F., Shen, P."The cytoprotective role of gemcitabine-induced autophagy associated with apoptosis inhibition in triple-negative MDA-MB-231 breast cancer cells". International Journal of Molecular Medicine 34, no. 1 (2014): 276-282. https://doi.org/10.3892/ijmm.2014.1772