IMGN901 consists of a potent maytansinoid attached to a CD56-binding monoclonal antibody through a disulfide linker in a Phase II clinical trial, which is a novel CD56-targeting anticancer agent and expressed on virtually all Merkel Cell Carcinoma (MCC) tumors (Figure 10) [70,71]. This evidence concerns the gene NCAM1 and Merkel cell skin cancer.