Galeterone

Post‐translational modifications (PTMs) of proteins are used by natural systems to expand beyond the 20 canonical amino acids. The variation introduced at the sequence level by PTMs after expression leads to changes in both the structure and function of proteins. PTMs expand the chemical repertoire from which new biomaterials can be constructed. Inspired by the post‐translational conjugation of cholesterol to proteins, we have synthesized five new hybrid lipid‐protein biomaterials called Sterol‐modified polypeptides (STaMPs). These STaMPs consist of an elastin‐like polypeptide (ELP) conjugated to a sterol, namely coprostanol, epicoprostanol, androstanol, galeterone, or dehydroepiandrosterone. We show that STaMPs exhibit sterol‐dependent self‐assembly behavior, ranging from predominantly monomeric random coils for the most hydrophilic sterols to spherical micelles for the most hydrophobic sterols. Furthermore, the sterols modify the typical LCST behavior of ELPs in a predictable fashion depending on the hydrophobicity of the sterol appended.

Despite therapeutic advancements, metastatic and nonmetastatic castration-resistant prostate cancer (mCRPC and nmCRPC) remain incurable due to drug resistance, partly due to Androgen receptor (AR) gene abnormalities and splice variants. An Augmented Artificial Intelligence (AI) -driven virtual drug screening using AtomNet® technology explored an 8 million small molecule library targeting AR allosteric sites to address resistance from AR mutations and AR-V7 splice variant. Screening identified compounds effectively reducing cancer cell growth, with ten actives in hormone-resistant cells. Dose-response assays identified compounds 1, 8, and 77 as most efficacious, exhibiting pIC₅₀ values from < 5.86-4.82. Docking and molecular dynamics (MD) simulations indicated that compound 77 targets both the allosteric site within the AF2 domain and the ligand binding domain of AR. Compounds 1, 8, and 77 were most active in 2D and 3D spheroid assay, with compound 77 showing significant activity in AR+ cells and modest effects in AR-null cells. These compounds surpassed treatments like enzalutamide and galeterone in inhibiting colony and sphere formation, indicating new therapeutic potential. These effects, partly due to AR inhibition, suggest additional mechanisms in inhibiting cancer growth and disrupting models, as seen in PC3 cells. Moreover, the docking analysis indicated that compounds 1, 8, and 77 exhibit binding affinity with the Glucocorticoid receptor (GR). Furthermore, immunofluorescence assay on PC3 cells, demonstrated that compound 77 inhibits the nuclear translocation of GR following dexamethasone treatment, which is used to induce GR nuclear translocation. Furthermore, these findings revealed that compound 77 significantly reduces the transcription of GR and its downstream gene FKBP5, a classical GR target gene. These results substantiate our hypothesis that compound 77, particularly engages in off-target interactions, thereby potentially disrupting cancer growth.