Rapamycin enhances the antiproliferative effect of transforming growth factor-β on MCF-7 human breast cancer cells

Guoping Wang1, Tao Yin1

  • 1Department of Oncology, Cancer Center, West China Hospital, Sichuan University and Collaborative Innovation Center of Biotherapy, Chengdu, Sichuan 610041, P.R. China.

Insights

Transforming growth factor-β (TGF-β) inhibits breast cancer cell proliferation by upregulating cyclin-dependent kinase inhibitors. Rapamycin enhances this effect, leading to apoptosis in MCF-7 cells.

Area of Science:

  • Oncology
  • Molecular Biology
  • Cell Biology

Background:

  • Transforming growth factor-β (TGF-β) is a cytokine regulating cellular proliferation.
  • Rapamycin targets the mammalian target of the rapamycin (mTOR) signaling pathway.
  • The combined effect of TGF-β and rapamycin on MCF-7 human breast cancer cells is not well understood.

Purpose of the Study:

  • To investigate the synergistic effects of TGF-β and rapamycin on MCF-7 human breast cancer cell proliferation.
  • To elucidate the molecular mechanisms underlying the interaction between TGF-β and rapamycin in breast cancer cells.

Main Methods:

  • MCF-7 human breast cancer cells were treated with TGF-β and/or rapamycin.
  • Cell proliferation was assessed.
  • Expression levels of cyclin-dependent kinase inhibitors (p14ARF, p15INK4b, p16INK4a, p21WAF1/CIP1) were analyzed.
  • Apoptosis was evaluated.

Main Results:

  • TGF-β demonstrated a significant growth-arresting effect on MCF-7 cells.
  • TGF-β stimulation led to increased expression of p14ARF, p15INK4b, p16INK4a, and p21WAF1/CIP1.
  • Rapamycin potentiated the antiproliferative action of TGF-β.
  • The combination of rapamycin and TGF-β induced apoptosis in MCF-7 cells.

Conclusions:

  • TGF-β exhibits antiproliferative effects on MCF-7 breast cancer cells, mediated by cyclin-dependent kinase inhibitors.
  • Rapamycin enhances the antiproliferative and pro-apoptotic effects of TGF-β in these cells.
  • The findings provide novel insights into the combined therapeutic potential of TGF-β and rapamycin in breast cancer treatment.

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