Tumor Biology

, Volume 35, Issue 2, pp 1169–1175 | Cite as

The role of Bax and Bcl-2 in gemcitabine-mediated cytotoxicity in uveal melanoma cells

  • Jing Wang
  • Renbing Jia
  • Yidan Zhang
  • Xiaofang Xu
  • Xin Song
  • Yixiong Zhou
  • He Zhang
  • Shengfang Ge
  • Xianqun Fan
Research Article


Gemcitabine (GEM), a new cytotoxic agent, was shown to be effective against uveal melanoma (UM) which is noted for its resistance to chemotherapy. In this study, we found the different sensitivities to GEM in UM cell lines and identified apoptotic cell death as the cause of GEM cytotoxicity. Both UM cell lines showed an increase in Bax protein levels and activation of cleaved Caspase 3. Additionally, SP6.5 cells showed a gradual increase in Bcl-2 expression over time, whereas VUP cells showed almost none. After interfering in the expression of Bcl-2, the sensitivity to GEM was obviously enhanced in SP6.5 cells. These results suggest that an increase in Bax plays a crucial role in apoptotic cell death induced by GEM in the absence of p53. Moreover, inhibition of Bcl-2 expression can efficiently enhance the cytotoxic effect of, and sensitivity to, GEM in UM cells.


Uveal melanoma Bcl-2 Bax Gemcitabine 



This work was supported by the National Natural Science Foundation of China grant (81100683, 81372469, 81372909), the Science and Technology Commission of Shanghai (13ZR1423600, 12ZR1417300) and the Shanghai PuJiang Program (13PJ1405700).

Conflicts of interest



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Copyright information

© International Society of Oncology and BioMarkers (ISOBM) 2013

Authors and Affiliations

  • Jing Wang
    • 1
  • Renbing Jia
    • 1
  • Yidan Zhang
    • 1
  • Xiaofang Xu
    • 1
  • Xin Song
    • 1
  • Yixiong Zhou
    • 1
  • He Zhang
    • 1
  • Shengfang Ge
    • 1
  • Xianqun Fan
    • 1
  1. 1.Department of Ophthalmology, Ninth People’s HospitalShanghai Jiaotong University School of MedicineShanghaiChina

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