Fibroblasts accumulated in TF under MTC conditions initiated substantial recruitment and adhesion pathways of N1-TANs, including CXCL2-CXCR2, COL1A2-CD44, and so on, while cleared N2-TANs via CXCL12-CXCR4. This evidence concerns the gene COL1A2 and medullary thyroid gland carcinoma.