HOXA5 and cancer: This might reflect the relative dependency of different signalling pathways in different cancers that are activated or repressed by downstream targets of HOXA5, although the wnt/β‐catenin pathway for example is activated by HOXA5 in oesophageal squamous cell cancer (in which it acts as an oncogene),83 but repressed by HOXA5 in colorectal cancer (in which it acts as a tumour suppressor),78 indicating that the explanation may be more complex.