The histologic distinction between PTC-PC and PTC's with a focal anaplastic thyroid cancer (ATC) component (denoted in the 2004 WHO classification as "papillary thyroid carcinoma with spindle and giant cell carcinoma", PTC-SGC) is debated, however the prognosis is thought to be different (excellent for PTC-PC, poor for PTC-SGC).
Using Western blot analysis, we found that Sin1 and p-AKT were detected at a greater level in cultured primary cells from aggressive PTC compared with conventional PTC as well as in cell lines of medullary and anaplastic thyroid carcinoma.
We characterized and utilized mouse cell lines derived from PTC and ATC tumors arising in genetically engineered mice with thyroid-specific expression of endogenous Braf(V600E/WT) and deletion of either Trp53 (p53) or Pten.
All miRNAs of 'set 2' were significantly upregulated in PTC (p<0.004) and downregulated in ATC (p<0.03); in PDTC only 3/5 were downregulated (p<0.011).
In conclusion, chromosomal abnormalities are frequent in ATCs associated with FTC, but uncommon in those associated with PTC and in ATCs with no associated differentiated thyroid cancer.