HOXD9 and poorly differentiated thyroid gland carcinoma: Through the examination of the GEO dataset GSE76039, which encompasses information pertaining to 20 patients diagnosed with ATC and 17 patients diagnosed with poorly differentiated thyroid carcinoma, gene set enrichment analysis (GSEA) analysis was performed on the differentially expressed genes from RNA-sequence data, the enrichment plots results showed that a higher level of HOXD9 in ATC patients is positively associated with the enrichment of upregulation of proliferation and downregulation of apoptosis (Fig. 2A, B).