7272 Antineoplastic Effect of Cabozantinib in Primary and Continuous Human Anaplastic Thyroid Cancer Cells

Abstract Disclosure: G. Elia: None. S. Ferrari: None. F. Ragusa: None. V. Mazzi: None. A. Patrizio: None. E. Balestri: None. C. Botrini: None. L. Rugani: None. E. Barozzi: None. C. La Motta: None. P. Fallahi: None. A. Antonelli: None. Anaplastic thyroid cancer (ATC) is a highly aggressive cancer with a low median survival of about 6-10 months. The standard treatment include surgery, external hyperfractionated radiation therapy, and chemotherapy. However, these therapies are not effective and new therapeutical approaches are needed. Tyrosine kinase inhibitors (TKI) are a class of drugs able to inhibit different pathways that results inappropriately activated in cancer cells.To date no studies evaluated the effect of cabozantinib in primary human ATC cells, and in ATC continuous cell line in vitro. We aimed to test the efficacy of cabozantinib a multiTKI acting against VEGFR 1,2, c-MET, and RET (recently approved for aggressive differentiated thyroid cancer) in primary human ATC cells, and in ATC continuous cell line (8305C, CAL-62) in vitro. Therefore, for primary ATC cells we collected surgical thyroidal tissues from five patients with ATC, from thyroid biopsy at the moment of first surgical operation, and we tested the effect of cabozantinib. Cabozantinib showed its efficacy in inhibiting cell proliferation, and also in increasing apoptosis (p < 0.05) both in primary and in continuous ATC cells. In conclusion, cabozantinib demonstrated a good antineoplastic activity in human ATC cells in vitro. These results open the way for a possible clinical use of cabozantinib in patients with ATC, and are important for a personalized therapeutic approach to be tailored to each patient avoiding the administration of ineffective drugs. Presentation: 6/1/2024