Conclusion
ADSCs upregulate MMP-2 levels of thyroid cancer cells through exocrine leptin, thereby promoting cancer cell migration, which may be one of the key mechanisms by which obesity increases the invasiveness of thyroid cancer.
Methods
ADSCs-conditioned medium (ADSC-CM) was collected to culture thyroid cancer cell lines TPC-1 cells and BCPAP cells. The effects of ADSCs on thyroid cancer cell proliferation were determined by CCK8 and EdU assays, and the effects on migration were determined by Transwell and wound closure assays. Leptin neutralizing antibodies (NAB) were added to ADSC-CM to block leptin. In animal experiments, TPC-1 cells and BCPAP cells were injected into the tail vein of nude mice, and the leptin receptor antagonist peptide allo-aca was injected subcutaneously to block the leptin pathway. The number and size of metastatic lung tumours were observed after 8 weeks.
Results
ADSC-CM significantly promoted the invasion and migration of thyroid cancer cells and upregulated their matrix metalloproteinase 2 (MMP-2) levels, while NAB with the addition of leptin reduced the invasion and migration of thyroid cancer cells and downregulated MMP-2 levels. Allo-aca treatment reduced the number of metastatic lung nodules formed by thyroid cancer cells in nude mice and reduced the diameter of metastatic lesions.