Background: Thyroid tumors exhibit a wide spectrum of histopathology and some thyroid carcinomas are reported to secrete various cytokines. However, it is obscure whether the differentiation of thyroid carcinoma is related to amount and variety of the secreted cytokines or how the secreted cytokines affect patients. We examined the secretion of cytokines and G-CSF in four anaplastic (K119, IAA, KOA2 and MSA) and two poorly differentiated (SMP and CTP) thyroid carcinoma cell lines and compared them with the clinical courses of patients.
Materials and methods: We collected conditioned medium from each of the cell lines and measured the release of cytokines (IL-1 alpha, IL-1 beta, IL-6, IL-8 and TNF-alpha) and growth factors (G-CSF, IGF-1) by each assay kits. IL-1 alpha, IL-8 and TNF-alpha were measured by ELISA. G-CSF was measured by one step sandwich EIA method. IL-1 beta and IGF-1 were measured by immunoradiometric assay. IL-6 was measured by chemiluminescent enzyme immunoassay.
Results: All four anaplastic and one poorly differentiated (SMP) thyroid cell lines secreted G-CSF and all examined cytokines except TNF-alpha. One poorly differentiated (CTP) thyroid cell line secreted IL-1 beta, IL-6 and IL-8. IGF-1 and TNF-alpha were not detected in all examined conditioned medium of cell lines. All four original patients with anaplastic thyroid carcinoma showed remarkable leukocytosis at terminal stage and in one of these patients, subfever without any infections was observed.
Conclusion: Anaplastic and poorly differentiated thyroid carcinomas have the ability to secrete various cytokines and G-CSF, which may affect clinical symptoms of the patients at terminal stage.