Immunohistochemical Expression of Vitamin-D Receptor in Laryngeal Squamous Cell Carcinoma

Laryngeal squamous cell carcinoma (LSCC) is the second most common primary malignant tumor of the respiratory tract after lung cancer and the second most common primary epithelial malignant tumor of the head and neck. The age of onset of LSCC is mostly between 50 and 70 years, with a male to female ratio of approximately 4:1 .According to estimates by the American Cancer Society, in the United States, approximately 12,470 new cases of laryngeal cancer will be diagnosed and 3,820 people will die from laryngeal cancer in 2022.

The nuclear vitamin D receptor (VDR) is involved in multiple pathways that have many points of convergence. Some of these pathways are implicated in carcinogenesis thus the suggestion that VDR has a role to play in the biology of cancer [3]. Recent evidence indicates that the active form of vitamin D (1alpha, 25-dihydroxycholecalciferol) (VD) exhibits several different effects on normal and cancerous cells, including up-regulation of anti- proliferation and pro-apoptotic factors, as well as inhibition of cell-cycle promoters and growth factor signaling pathways. Thus it is useful as an anti-neoplastic agent in several human malignancies.

Studies in cell and animal model systems, as well as clinical trials have recognized the potential usefulness of VD and VD analogues as agents that enhance the anti-proliferative/cytotoxic effects of chemotherapy and ionizing radiation. Thus, at concentrations that produce limited hypercalcemia, these agents may be used as adjuncts to conventional chemotherapy and radiotherapy. We aim to analyze the expression of VDR in LSCC to determine potential for active VD therapy in such patients.