Immunohistochemical expression of transient receptor potential vanilloid 1 in World Health Organization grade IV astrocytoma, oral squamous cell carcinoma and bladder carcinoma

Transient receptor potential vanilloid 1 (TRPV1), an ion channel receptor, has been identified to have a variety of functions in cancer, with overexpression associated with tumor suppression as well as promotion, making it an attractive but challenging target for cancer research and therapy. The study aimed to evaluate the immunohistochemical expression of TRPV1 in various cancer grades, including astrocytoma, meningioma, bladder carcinoma, oral squamous cell carcinoma, and normal tissues. A total of 60 patients diagnosed with cancer from King Edward Medical University were studied. All the specimens were prepared for immunohistochemistry by fixing them in formalin and embedding them in paraffin. Tissue consecutive sections were collected on L-lysine-coated slides. To determine the labeling index (i.e., % of labeled cells, LI) for the TRPV1 antibody, two observers independently assessed 10 random non-overlapping fields (×400 total magnification) for each sample and counted manually 100 tumor cells in each field by using an ocular grid. High expression of TRPV1 was seen in the advanced stage of bladder cancer, while decreased expression was seen in low-grade bladder cancer. Very low expression of TRPV1 was seen in breast cancer. Very high expression of TRPV1 was seen in tissue samples of World Health Organization grade 4 astrocytoma. Tissue samples of oral cancer also showed increased expression of TRPV1. Meningioma (negative control) had no expression of TRPV1, and colon cancer (positive control) had high expression. The current study demonstrates distinct patterns of TRPV1 immunohistochemical expression across several cancer types, underlining the context-dependent nature of TRPV1’s function in cancer progression. Further studies should be conducted to further investigate the therapeutic potential of TRPV1.100.