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The angiogenic role of the alpha 9-nicotinic acetylcholine receptor in triple-negative breast cancers

  • 0International Ph.D. Program in Medicine, College of Medicine, Taipei Medical University, Taipei, 11031, Taiwan.
Angiogenesis +

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August 23, 2024

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August 23, 2024

View abstract on PubMed

Summary

This summary is machine-generated.

Nicotine promotes breast cancer growth via alpha-9 nicotinic acetylcholine receptors (α9-nAChRs). A novel bispecific antibody targeting α9-nAChRs inhibits nicotine-induced angiogenesis and may offer a new cancer therapy.

Area Of Science

  • Oncology
  • Molecular Biology
  • Pharmacology

Background

  • Nicotine exposure is linked to cancer progression.
  • Nicotinic acetylcholine receptors (nAChRs), particularly α9-nAChRs, are upregulated in advanced breast cancers.
  • α9-nAChR activation promotes breast cancer cell proliferation and migration.

Purpose Of The Study

  • To investigate the role of α9-nAChRs in nicotine-induced angiogenesis in breast cancer.
  • To develop and evaluate a novel bispecific antibody (α9 BsAb) targeting α9-nAChRs for potential cancer therapy.

Main Methods

  • Generation of a novel anti-α9-nAChR and mPEG bispecific antibody (α9 BsAb).
  • In vitro assays assessing endothelial cell tube formation and in vivo angiogenesis models (Matrigel plug, MTAMs).
  • Analysis of signaling pathways including HIF-2α, VEGF-A, VEGFR2, and MMP9.
  • Validation using shRNA to silence α9-nAChR expression.

Main Results

  • α9 BsAbs significantly reduced nicotine-induced endothelial cell tube formation and blood vessel development.
  • α9 BsAbs inhibited key angiogenic factors (HIF-2α, VEGF-A, p-VEGFR2, VEGFR2, MMP9) in breast cancer cells.
  • α9-nAChR silencing via shRNA confirmed the receptor's role in promoting nicotine-induced angiogenesis.
  • The study identified α9-nAChR as a critical mediator of nicotine-induced angiogenesis.

Conclusions

  • α9-nAChRs play a significant role in nicotine-induced angiogenesis in breast cancer.
  • The developed α9 BsAb effectively inhibits α9-nAChR-mediated angiogenesis.
  • α9 BsAb represents a promising therapeutic candidate for α9-nAChR-positive cancers.

Keywords:

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