CDKN2B and neoplasm: Furthermore, the molecular features of the tumours were found to resemble that of human MM tumours, including activation of Akt; homozygous deletion of tumour suppressor genes p16 (Ink4A), p14 (ARF)/p19(Arf), and p15(Ink4B); and loss of the Nf2 protein, Merlin (44).