In Vitro Anti-Prostate Cancer Activity of Two Ebselen Analogues.

Scientific research has been underway for decades in order to develop an effective anticancer drug, and it has become crucial to find a novel and effective chemotherapeutics in the case of prostate cancer treatment. Ebselen derivatives have been shown to possess a variety of biological activities, including cytostatic and cytotoxic action against tumor cells. In this study, the cytotoxic effect and anticancer mechanism of action of two organoselenium compounds- (N-allyl-1,2-benzisoselenazol-3(2H)-one (N-allyl-BS) and N-(3-methylbutyl)-1,2-benzisoselenazol-3(2H)-one) (N-(3-mb)-BS)-were investigated on two phenotypically different prostate cancer cell lines DU 145 and PC-3. The influence of analyzed compounds on the viability parameter was also assessed on normal prostate cell line PNT1A. The results showed that both organoselenium compounds (OSCs) efficiently inhibited cancer cell proliferation, whereas normal PNT1A cells were less sensitive to the analazyed ebselen analouges. Both OSCs induced G2/M cell cycle arrest and prompted cell death through apoptosis. The detection of cleaved Poly (ADP-ribose) Polymerase (PARP) confirmed this. In addition, N-allyl-BS and N-(3-m)-b-BS increased the level of reactive oxygen species (ROS) formation, however only N-allyl-BS induced DNA damage. Based on our data, we assume that OSCs' anticancer action can be associated with oxidative stress induction and inactivation of the Akt- dependent signalling pathway. In conclusion, our data demonstrate that ebselen derivatives showed strong cytotoxic efficiency towards prostate cancer cells and may be elucidated as a novel, potent anticancer agent.

Seleninic Acid Potassium Salts as Water-Soluble Biocatalysts with Enhanced Bioavailability.

Organoselenium compounds are well-known glutathione peroxidase (GPx) mimetics that possess antioxidants/prooxidant properties and are able to modulate the concentration of reactive oxygen species (ROS), preventing oxidative stress in normal cells or inducing ROS formation in cancer cells leading to apoptosis. The purpose of this study was the synthesis of potent GPx mimics with antioxidant and anticancer activity along with improved bioavailability, as a result of good solubility in protic solvents. As a result of our research, glutathione peroxidase (GPx) mimetics in the form of water-soluble benzeneseleninic acid salts were obtained. The procedure was based on the synthesis of 2-(N-alkylcarboxyamido)benzeneselenenic acids, through the oxidation of benzisoselenazol-3(2H)-ones or analogous arenediselenides with an amido group, which were further converted to corresponding potassium salts by the treatment with potassium tert-butanolate. All derivatives were tested as potential antioxidants and anticancer agents. The areneseleninic acid salts were significantly better peroxide scavengers than analogous acids and the well-known organoselenium antioxidant ebselen. The highest activity was observed for the 2-(N-ethylcarboxyamido)benzeneselenenic acid potassium salt. The strongest cytotoxic effect against breast cancer (MCF-7) and human promyelocytic leukemia (HL-60) cell lines was found for 2-(N-cyclohexylcarboxyamido)benzeneselenenic acid potassium salt and the 2-(N-ethylcarboxyamido)benzeneselenenic acid, respectively. The structure-activity correlations, including the differences in reactivity of benzeneseleninic acids and corresponding salts were evaluated.

Bioselectivity Induced by Chirality of New Terpenyl Organoselenium Compounds.

A series of new chiral benzisoselenazol-3(2H)-ones substituted on the nitrogen atom with three monoterpene moieties-p-menthane, pinane and carane-was synthesized. The compounds were obtained by the reaction of 2-(chloroseleno)benzoyl chloride with an appropriate terpene amine, first synthesized by a multistep methodology starting from the corresponding alcohol (p-menthane system) or alkene (pinene and carene systems). Compounds were tested as antioxidants and anticancer agents. The N-isopinocampheyl-1,2-benzisoselenazol-3(2H)-one was the best peroxide scavenger and antiproliferative agent on the human promyelocytic leukemia cell line HL-60. The N-menthyl-1,2-benzisoselenazol-3(2H)-one revealed the highest anticancer potential towards breast cancer line MCF-7. The influence of structure and chirality on the bio-activity of the obtained organoselenium compounds was thoroughly evaluated.