PTPRZ1 and Miyoshi myopathy: Furthermore, the analyses of data from MM patients enrolled in the HOVON65/GMMG-HD4 trial were described in a European study that identified three additional subgroups of MM [73] including the nuclear factor kappa light chain-enhancer (NF-kB) subgroup, the Cancer testis antigen (CTA) subgroup characterized by high proliferation index, and the PRL3 subgroup characterized by up-regulation of protein tyrosine phosphatases PRL-3 and PTPRZ1.