As HDAC4 has been known to decrease total and acetylated Runx2 [75] and HIF-1α [76] through its deacetylation and transcriptional repressor activities, reduced expression of HDAC4 results in higher levels of Runx2 and HIF-1α, thereby increasing transcription of VEGF and its angiogenic activity on chondrosarcoma cells (Table 1). This evidence concerns the gene RUNX2 and chondrosarcoma.