Arsenic Trioxide Reactivates Proteasome-Dependent Degradation of Mutant p53 Protein in Cancer Cells in Part via Enhanced Expression of Pirh2 E3 Ligase
Figure 6
Arsenic trioxide cooperates with HSP90 or HDAC inhibitor to decrease mutant p53 expression and tumor cell proliferation.
(A–B) Western blots were prepared with extracts from HaCaT (A) and MIA PaCa-2 (B) cells, which were untreated or treated with 1 µM 17AAG or 2 µM SAHA for 12 h. The blots were then probed with antibodies against Pirh2 and actin, respectively. (C–D) Western blots were prepared with extracts from HaCaT (C) and MIA PaCa-2 (D) cells, which were untreated or treated with 7.5 µM ATO, 1 µM 17AAG or 2 µM SAHA, alone or in combination for 12 h. The blots were then probed with antibodies against p53 and actin, respectively. (E–F) HaCaT (E) and MIA PaCa-2 (F) cells were treated as in (C–D) for 24 h. Surviving cells from both control and treated groups were counted and presented as Mean ± SD from three separate experiments. *, p<0.05.