UBE2O and Miyoshi myopathy: However, when these MM cell lines infected with lentiviral UBE2O were subjected to cell cycle analysis, the results showed that UBE2O arrested both RPMI-8226 and LP1 cells at the S or S/M phases (Fig. 5f), which was out of expectation because cyclin D2 is a key player in control the progress of cell cycle from G1 to S phase.