Figure 4.

Androgen Receptor and PARG activities are required for optimal BER capacity in androgen-dependent prostate cancer cells. BER capacity was measured by incubating a random DNA sequence substrate containing an abasic site (a THF residue) with cell extracts from LNCaP (a,b) and LAPC4 (c,d) cells under the conditions described in the Materials and Methods. Lane 1 is the untreated substrate. Lane 2 corresponds to substrate treated with 1 nM APE1. All subsequent lanes correspond to reaction mixtures supplemented with extracts of cells grown in FBS or CSS and treated as indicated. Substrate was ³²P-labeled at the 5′-end of the damaged strand as shown in 3b. The signal was detected with phosphoimager, and the intensity of the ligated product was quantified by the Quantity One software. Signal and standard deviation were calculated and presented as a bar graph for LNCaP (b) and LAPC4 (d). The experiments were repeated three times. Representative gels are shown. (*p ≤ 0.05; **p ≤ 0.01; ****p ≤ 0.0001). Experiments in a and c were performed at least 3 times. Calculations in b and d were done for 3 independent experiments.