Table 1

AXIN1 siRNAs confer sensitivity to PLX4720-mediated apoptosis in previously resistant cell lines. A2058, SKMEL5, and SKMEL28 cells were transfected with control siRNA or siRNA targeting AXIN1. Forty-eight hours after transfection, cells were treated with the indicated conditions for 24 hours and analyzed for apoptosis by flow cytometry for cleaved caspase-3. L CM and W3A CM indicate control and WNT3A-conditioned media, respectively. PLX4720 (2 μM) was used where indicated. Values represent the average number of cleaved caspase-3–positive cells ± SD in three or more biologic replicates. Statistically significant differences between control and AXIN1 siRNA for different conditions within each cell line are indicated by an asterisk (*) denoting a P < 0.001 by two-way ANOVA with Bonferonni’s post-test comparison.

Melanoma cell
line
Control siRNAAXIN1 siRNA
L CM
DMSO
W3A CM
DMSO
L CM
PLX4720
W3A CM
PLX4720
L CM
DMSO
W3A CM
DMSO
L CM
PLX4720
W3A CM
PLX4720
A20581.18 ± 0.301.37 ± 0.082.20 ± 0.433.16 ± 0.403.78 ± 0.515.23 ± 0.9421.27 ± 2.11*21.77 ± 4.36*
SKMEL281.13 ± 0.251.00 ± 0.401.81 ± 0.355.34 ± 1.551.03 ± 0.240.71 ± 0.3222.20 ± 5.43*30.97 ± 3.65*
SKMEL51.01 ± 0.140.96 ± 0.152.20 ± 0.172.72 ± 0.182.25 ± 0.522.45 ± 0.1210.80 ± 1.06*12.10 ± 1.15*