Optimization of (Phenylmethylidene)-hydantoins as Prostate Cancer Migration Inhibitors: SAR-Directed Design, Synthesis, and Pharmacophore Modeling

Marine Natural Products with Activities against Prostate Cancer: Recent Discoveries

Prostate cancer is the most common cancer in men, with over 52,000 new cases diagnosed every year. Diagnostics and early treatment are potentially hindered by variations in screening protocols, still largely reliant on serum levels of acid phosphatase and prostate-specific antigen, with tumour diagnosis and grading relying on histopathological examination. Current treatment interventions vary in terms of efficacy, cost and severity of side effects, and relapse can be aggressive and resistant to the current standard of care. For these reasons, the scientific community is looking for new chemotherapeutic agents. This review reports compounds and extracts derived from marine organisms as a potential source of new drugs against prostate cancer. Whilst there are several marine-derived compounds against other cancers, such as multiple myeloma, leukemia, breast and lung cancer, already available in the market, the presently collated findings show how the marine environment can be considered to hold potential as a new drug source for prostate cancer, as well. This review presents information on compounds presently in clinical trials, as well as new compounds/extracts that may enter trials in the future. We summarise information regarding mechanisms of action and active concentrations.

Bioactive natural products from marine sponges belonging to family Hymedesmiidae

Natural products of marine origin exhibit extensive biological activities, and display a vital role in the exploration of new compounds for drug development. Marine sponges have been reported at the top with respect to the discovery of biologically active metabolites that have potential pharmaceutical applications. The family Hymedesmiidae belonging to the Demospongiae class includes ten accepted genera, of which four genera were explored for their bioactive metabolites, namely Phorbas, Hamigera, Hemimycale, and Kirkpatrickia. Genus Phorbas has received more attention due to the isolation of various classes of compounds with unique structures mainly diterpenes, alkaloids, sesterterpenes, and steroids that exhibited diverse biological activities including: antiviral, antimicrobial, and anti-inflammatory, whereas anticancer compounds predominated. This review focuses on the isolated secondary metabolites from family Hymedesmiidae with their biological potential and covers the literature from 1989 to 2020.

Natural products of marine origin exhibit extensive biological activities, and display a vital role in the exploration of new compounds for drug development.

Marine natural products-inspired phenylmethylene hydantoins with potent in vitro and in vivo antitumor activities via suppression of Brk and FAK signaling

Breast and prostate cancers are among the most common cancers worldwide with devastating statistics for the metastatic, chemotherapy- and radiotherapy-resistant phenotypes. Novel therapies interfering with new and/or multiple pathways involved in the pathology of cancer are urgently needed. Preliminary results showed that the marine natural product Z-4-hydroxyphenylmethylene hydantoin (PMH, ) and its 4-ethylthio-analog (SEth, ) promoted tight junction formation and showed anti-invasive and anti-migratory activities in vitro against metastatic prostate cancer cells and inhibited tumor growth and micrometastases in distant organs in orthotopic and transgenic mice models. This study focuses on the design and synthesis of second-generation PMHs with enhanced antitumor activities. A series of substituted benzaldehydes was selected based on earlier SAR studies and reacted with hydantoin to yield 11 new compounds . Compounds were evaluated for their antiproliferative, antimigratory and anti-invasive properties in vitro against the human mammary and prostate cancer cell lines MDA-MB-231 and PC-3, respectively. A Western blot analysis of the most active analog showed its ability to suppress the expression of the total levels of c-Met and FAK, with subsequent reduction of their phosphorylated (activated) levels in MDA-MB-231 cells. In addition, also inhibited Brk, paxillin and Rac1 phosphorylation. was formulated using hydroxypropyl β-cyclodextrin (HPCD) to improve its solubility and was further evaluated in a nude mice xenograft model using MDA-MB-231/GFP cells. PMH reduced breast tumor growth and suppressed Ki-67, CD31, p-Brk and p-FAK expression in tumor samples. Thus, is a potential lead for the control of invasive breast malignancies.

Subereamolline A as a potent breast cancer migration, invasion and proliferation inhibitor and bioactive dibrominated alkaloids from the Red Sea sponge Pseudoceratina arabica

A new collection of several Red Sea sponges was investigated for the discovery of potential breast cancer migration inhibitors. Extracts of the Verongid sponges Pseudoceratina arabica and Suberea mollis were selected. Bioassay-directed fractionation of both sponges, using the wound-healing assay, resulted into the isolation of several new and known brominated alkaloids. Active fractions of the sponge Pseudoceratina arabica afforded five new alkaloids, ceratinines A-E (2-6), together with the known alkaloids moloka'iamine (1), hydroxymoloka'iamine (7) and moloka'iakitamide (8). The active fraction of the sponge Suberea mollis afforded the three known alkaloids subereamolline A (9), aerothionin (10) and homoaerothionin (11). Ceratinine B (3) possesses an unprecedented 5,7-dibrominated dihydroindole moiety with an epoxy ring on the side chain of a fully substituted aromatic moiety. Ceratinines D (5) and E (6) possess a terminal formamide moiety at the ethylamine side chain. Subereamolline A (9) potently inhibited the migration and invasion of the highly metastatic human breast cancer cells MDA-MB-231 at the nanomolar doses. Subereamolline A and related brominated alkaloids are novel scaffolds appropriate for further future use for the control of metastatic breast cancer.