CD274 and Miyoshi myopathy: Tamura et al. showed that RPMI8226 and KMS-34 MM cells expressing surface PD-L1 had a proliferative advantage over cells from the same line that did not express PD-L1, as demonstrated by higher fraction of cells in the G2/M phase, higher levels of BrdU incorporation, percentage of Ki67 positivity, and more rapid proliferation in cell cultures [11].