Aim: To study the effects of Paclitaxel (Ptx), γ-irradiation (IR) and their combination on the growth of xenografted tumors derived from undifferentiated thyroid cancer cells.
Materials and methods: Experiments were performed in nude mice with tumors developing from implanted undifferentiated thyroid carcinoma cells (FRO). Animals were treated with Ptx i.p. and exposed locally to a single dose of 5 Gy of IR. Apoptosis in situ was detected using ApopTag Peroxidase Kit.
Results: In the in vivo experiments, IR significantly inhibited but did not abrogate tumor growth. Ptx effect was stronger, and the combination therapy with Ptx and IR led to the decrease of tumor volume to 0-0.3% of the control (P < 0.01). The systemic administration of Ptx to the animals with advanced tumors resulted in a profound tumor growth suppression and in apoptosis in tumor tissues in time-dependent manner.
Conclusion: The combination of Ptx and IR is a promising strategy for further preclinical and clinical trials aimed at the development of new therapeutic approaches to the treatment of undifferentiated thyroid cancer.