MICA and cancer: Some immune-edited cancers that downregulate their MHC Class I molecule as part of their immune evasion tactic may be subjected to lysis by natural killer (NK) cells that become activated through the absence of inhibitory signals normally provided the MHC Class I molecules or by the presence of stress markers MIC-A or MIC-B on cancer cells (Long et al., 2013; Campbell and Hasegawa, 2013).