Figure 3.

Human HOX clusters and their expression during development. (A) HOX genes organized in four clusters (A, B, C, D). Cluster designation is on the left, and Paralogous (1–13) are indicated at the top. HOX genes, which were proven to be methylated or demethylated in cancer, are outlined in black, and the noncoding RNAs involved in cancer are marked in the approximate position from which there are transcribed (mir, microRNAs; AS, antisense RNAs). (B) HOX gene expression along the anterior–posterior axis (head and trunk) and along the proximal–distal axis of limbs.