Fig. 1.

Hydrogen peroxide (H₂O₂) induces MLL gene cleavage in NPC cells. SUNE1 cells were treated with either 0 μM, 10 μM, 50 μM, 100 μM, 500 μM, 1 mM or 10 mM of H₂O₂ for 20 h (lanes 1–7 respectively). Genomic DNA was extracted and modified for IPCR as described in Materials and Methods. DNA was digested with Msc I during the modification. Side arrow shows the 2.2 kb band resulting from amplification of the intact MLL gene. Side bracket shows bands smaller than 2.2 kb resulting from amplification of cleaved MLL gene. M₁ represents 1 kb DNA marker