CXXC5 and neoplasm: KANK1 is a potential tumour suppressor gene and is downregulated in more than half of human malignant peripheral nerve sheath tumours (MPNSTs).78 Overexpression of KANK1 could induce CXXC5 expression to promote cell apoptosis in MPNSTs.79 The retinoic acid receptor (RARα) acts as a transcription factor when bound to all‐trans retinoic acid, facilitating terminal maturation of leukaemic blasts.80 The CXXC5 promoter contains a retinoid‐responsive element at −3116 bp.