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Biology subjects

Hill, B. L.

Publications and source records attributed to Hill, B. L..

3 recordsLinked to original sources

T2R5 agonist phendione decreases cell viability and induces apoptosis in head and neck squamous cell carcinoma

Bitter taste receptors (T2Rs), a family of G-protein coupled receptors, are emerging as potential therapeutic targets in head and neck squamous cell carcinoma (HNSCC). Phendione, a known T2R5 agonist, has not been previously investigated in HNSCC. Here, we show that phendione activates endogenously expressed T2R5 in HNSCC cells and ex vivo tumor samples, inducing sustained calcium responses, reducing cell viability, and promoting apoptosis through a T2R5-dependent mechanism. Analysis of The Cancer Genome Atlas data revealed that high T2R5 expression in HNSCC tumors correlates with improved long-term disease-specific survival, suggesting a potential tumor-suppressive role for T2R5. These findings highlight T2R5 as a promising therapeutic target in HNSCC and support further investigation of phendione or other T2R5 agonists as potential anti-cancer agents.

cancer biology↗

Pseudomonas aeruginosa metabolite 3-oxo-C12HSL induces apoptosis through T2R14 and the mitochondrial calcium uniporter

Head and neck squamous cell carcinomas (HNSCCs) arise in the mucosal lining of the upper aerodigestive tract. HNSCCs have high mortality rates and current treatments can be associated with severe morbidities. It is vital to discover effective, minimally invasive therapies that improve survival and quality of life. We previously discovered that bitter taste receptor 14 (T2R14), a GPCR, kills HNSCC cells when activated by bitter agonists. We are now investigating endogenous bitter ligands that exist in HNSCC tumor microenvironment (TME). The TME includes cells, signaling molecules, and microbes that can greatly influence treatment responses and overall prognosis in HNSCC. Pseudomonas aeruginosa is a gram-negative bacterium that colonizes/infects HNSCC patients. 3-oxo-C12SHL is a quorum-sensing N-acyl homoserine lactone (AHL) secreted by P. aeruginosa which is also a bitter compound. 3-oxo-C12HSL induces apoptosis but this has never been linked to T2R activation. We hypothesized that 3-oxo-C12HSL induces apoptosis in HNSCC via T2R14. We show that 3-oxo-C12HSL activates intracellular Ca2+ responses in HNSCC cells. This is inhibited with T2R14 antagonization. 3-oxo-C12HSL may activate additional Ca2+ channels as the Ca2+ dynamics are independent from store-operated calcium entry (SOCE). 3-oxo-C12HSL inhibits cell viability, depolarizes mitochondria, and produces ROS. This induces apoptosis in HNSCC cells. In a comparative screen of quorum-sensing AHLs, 3-oxo-C12HSL was the only AHL that elicited both a Ca2+ response and reduced cell viability. These results suggest that P. aeruginosa may play a significant role in modulating an anti-tumor TME through 3-oxo-C12HSL. Moreover, 3-oxo-C12HSL could be a novel, higher-affinity bitter therapeutic for HNSCC. Further research is warranted to elucidate the mechanisms of other endogenous T2R agonists present in the TME.

physiology↗

Bitter Taste Receptor Agonists Induce Apoptosis in Papillary Thyroid Cancer

BackgroundPapillary thyroid carcinoma (PTC) is the most common thyroid malignancy, with a 20% recurrence rate. Bitter taste receptors (T2Rs) and their genes (TAS2Rs) may regulate survival in solid tumors. This study examined T2R expression and function in PTC cells. MethodsThree PTC cell lines (MDA-T32, MDA-T68, MDA-T85) were analyzed for expression using RT-qPCR and immunofluorescence. Live cell imaging measured calcium responses to six bitter agonists. Viability and apoptosis effects were assessed using crystal violet and caspase 3/7 activation assays. Genome analysis of survival was conducted. ResultsTAS2R14 was consistently highly expressed in all cell lines. Five bitter agonists produced significant calcium responses across all cell lines. All bitter agonists significantly decreased viability and induced apoptosis. Higher TAS2R14 expression correlated with better progression-free survival in patients (p<0.05). ConclusionsT2R activation by bitter agonists induces apoptosis and higher TAS2R expression is associated with survival, suggesting potential therapeutic relevance in thyroid cancer management.

cancer biology↗