alpha-ionone and Prostatic-Neoplasms

Olfactory receptors are G protein-coupled receptors. Some of them are expressed in tumor cells, such as the OR51E2 receptor overexpressed in LNCaP prostate cancer cells. It is considered a prostate tumor marker. We previously demonstrated that this receptor is able to promote LNCaP cell invasiveness in vitro upon stimulation with its odorant agonist β-ionone, leading to increased generation of metastases in vivo. In the present study, we show that even a relatively short exposure to β-ionone is sufficient to promote metastasis emergence. Moreover, α-ionone, considered an OR51E2 antagonist, in fact promotes prostate tumor growth in vivo. The combination of α-ionone with β-ionone triggers a higher increase in the total tumor burden than each molecule alone. To support the in vivo results, we demonstrate in vitro that α-ionone is a real agonist of OR51E2, mainly sustaining LNCaP cell growth, while β-ionone mainly promotes cell invasiveness. So, while structurally close, α-ionone and β-ionone appear to induce different cellular effects, both leading to increased tumor aggressiveness. This behaviour could be explained by a different coupling to downstream effectors, as it has been reported for the so-called biased ligands of other G protein-coupled receptors.

Topics: Animals; Cell Line, Tumor; Cell Movement; Disease Progression; Humans; Male; Mice; Neoplasm Metastasis; Neoplasm Proteins; Neoplasm Transplantation; Norisoprenoids; Prostatic Neoplasms; Receptors, Odorant; Up-Regulation

We report the SAR studies of 43 ionone-based chalcones that demonstrate substantial in vitro anti-proliferative activities in LNCaP, MDA-PCa-2b, 22Rv1, C4-2B and PC-3 prostate cancer cell lines. Compound 25 with an IC(50) value of 0.74 microM in LNCaP cells potently antagonizes DHT-induced transactivation of the wild type and the clinically relevant T877A, W741C and H874Y mutated androgen receptors, representing a novel chalcone as pan-antagonist of androgen receptor.

Topics: Androgen Receptor Antagonists; Animals; Antineoplastic Agents; Chalcones; Combinatorial Chemistry Techniques; Drug Screening Assays, Antitumor; Humans; Male; Mice; Molecular Structure; Mutation; Norisoprenoids; Prostatic Neoplasms; Receptors, Androgen; Structure-Activity Relationship