Bitter Taste Receptor Agonists Induce Apoptosis in Papillary Thyroid Cancer

Kimberly Wei1, Brianna L Hill1, Joel C Thompson1

  • 1Department of Otorhinolaryngology - Head and Neck Surgery, University of Pennsylvania, Perelman School of Medicine, Philadelphia, Pennsylvania, USA.

Head & Neck
|March 5, 2025
PubMed
Abstract

Insights

Bitter taste receptors (T2Rs) activation in papillary thyroid cancer (PTC) cells induces apoptosis and improves patient survival. Higher TAS2R expression correlates with better outcomes, suggesting therapeutic potential for T2R agonists in thyroid cancer.

Area of Science:

  • Oncology
  • Molecular Biology
  • Pharmacology

Background:

  • Papillary thyroid carcinoma (PTC) is the most prevalent thyroid malignancy, characterized by a significant recurrence rate.
  • Bitter taste receptors (T2Rs) and their genes (TAS2Rs) are implicated in regulating cell survival within solid tumors.
  • The expression and functional role of T2Rs in PTC cells remain largely unexplored.

Purpose of the Study:

  • To investigate the expression of T2Rs in human PTC cell lines.
  • To determine the functional effects of bitter agonist activation on PTC cell viability and apoptosis.
  • To explore the correlation between T2R expression and patient survival outcomes in PTC.

Main Methods:

  • Analysis of T2R gene and protein expression in three PTC cell lines (MDA-T32, MDA-T68, MDA-T85) using RT-qPCR and immunofluorescence.
  • Measurement of intracellular calcium responses to bitter agonists via live cell imaging.
  • Assessment of cell viability and apoptosis using crystal violet staining and caspase 3/7 activation assays.
  • Correlation analysis between TAS2R14 expression and patient progression-free survival.

Main Results:

  • TAS2R14 was found to be highly expressed across all examined PTC cell lines.
  • Activation by five distinct bitter agonists elicited significant calcium responses in both cytoplasmic and mitochondrial compartments.
  • Exposure to bitter agonists markedly reduced cell viability and induced apoptosis in PTC cells.
  • A significant positive correlation was observed between higher TAS2R14 expression and improved progression-free survival in PTC patients (p < 0.05).

Conclusions:

  • Activation of T2Rs by bitter agonists triggers apoptosis in PTC cells.
  • Elevated T2R expression is associated with enhanced survival outcomes in patients with thyroid cancer.
  • These findings highlight the potential therapeutic utility of T2R agonists in managing thyroid cancer.

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