E2F1 and Miyoshi myopathy: Accordingly, we also found a significant inhibition of PVR/CD155 mRNA levels in DETA-NO + caffeine-treated cells (Figure 4E) and, in addition, up-regulation of PVR/CD155 expression was significantly inhibited in SKO-007(J3) cells in which the expression of E2F1 was reduced by shRNA interference (already described in [24]), a transcription factor activated/stabilized by ATM/ATR and Chk2 [41-43] and recently shown to upregulate the expression of PVR/CD155 in MM cells exposed to genotoxic drugs [24].