The effect of MEL-6 on gene expression in LNCaP cells
Prostate cancer patients benefit from treatment with androgen receptor signaling inhibitors such as AR antagonists. The emergence of resistance to the clinically applied AR antagonists opens up the need for development of alternative AR antagonists. We show here the development of a novel AR antagonists that is structurally different from enzalutamide. Moreover, MEL-6 remains active in the presence of several AR mutations (T877A, W741C and F876L) that are found in patients resistant to hydroxyflutamide, bicalutamide and enzalutamide.  To validate the androgen receptor (AR) as the target of our experimental AR antagonist, MEL-6, we investigated the effect of MEL-6 treatment on the prostate cancer cell line, LNCaP. Overall design: To identify the androgen receptor as the target of MEL-6 we performed RNASeq analysis. LNCaP cells were plated in medium with 5% dextran-coated charcoal (DCC) treated FCS at a density of 1 million cells/well in 6-well plates. After 24 hours of steroid starvation the cells were treated with vehicle (DMSO), 1 nM of the androgen R1881 or 1 nM R1881 supplemented with 10 µM of MEL-6 for 18 hours. The list of differentially expressed genes of the R1881 + MEL-6 vs R1881 comparison was consequently analyzed using Gene set enrichment analysis.