Tumor Necrosis Factor-Related Apoptosis-Inducing Ligand-Induced Apoptosis in Prostate Cancer Cells after Treatment with Xanthohumol—A Natural Compound Present in Humulus lupulus L.

Abstract

TRAIL (tumor necrosis factor-related apoptosis-inducing ligand) is an endogenous ligand, which plays role in immune surveillance and anti-tumor immunity. It has ability to selectively kill tumor cells showing no toxicity to normal cells. We tested the apoptotic and cytotoxic activities of xanthohumol, a prenylated chalcone found in Humulus lupulus on androgen-sensitive human prostate adenocarcinoma cells (LNCaP) in combination with TRAIL. Cytotoxicity was measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide tetrazolium reduction assay (MTT) and lactate dehydrogenase assay (LDH). The expression of death receptors (DR4/TRAIL-R1 and DR5/TRAIL-R2) and apoptosis were detected using flow cytometry. We examined mitochondrial membrane potential (ΔΨm) by DePsipher reagent using fluorescence microscopy. The intracellular expression of proteins was evaluated by Western blotting. Our study showed that xanthohumol enhanced cytotoxic and apoptotic effects of TRAIL. The tested compounds activated caspases-3, -8, -9, Bid, and increased the expression of Bax. They also decreased expression of Bcl-xL and decreased mitochondrial membrane potential, while the expression of death receptors was not changed. The findings suggest that xanthohumol is a compound of potential use in chemoprevention of prostate cancer due to its sensitization of cancer cells to TRAIL-mediated apoptosis.

Phenols and Melanoidins as Natural Antioxidants in Beer. Structure, Reactivity and Antioxidant Activity

“…Xanthohumol displays many bioactive effects such as antioxidant, anti-inflammatory, anti-microbial, hypoglycemic, and anti-obesity [32,33]. In particular, this compound is effective against different types of cancer [30] among which are: breast [34], ovarian [34], prostate [35], of colon [36] and pancreas [37] as well as being effective against leukemia [38] and protecting DNA against oxidative damage [39]. With a xanthohumol content of around 200 mg/L, beer is the principal source of this molecule in the human diet [33,40].…”

Mutagenic, genotoxic and cytotoxic studies of invasive corals Tubastraea coccinea and Tubastraea tagusensis

“…Both colorimetric assays have the same focus of analysis, cell death, but through different pathways. While the WST‐1 reagent assay allows the observation of cell death by interference with mitochondrial enzyme activity (Ngamwongsatit et al, ), the LDH release assay explores the same phenomenon through cell membrane disruption (Kłósek et al, ). The use of both methodologies promoted an evaluation of the cytotoxicity of the samples on the cell lines used in the in vitro micronucleus assay.…”

“…With the membrane rupture, this enzyme is released into extracellular medium and acts on the oxidative reaction of lactate to pyruvate, leading to a reduction of nicotinamide adenine dinucleotide molecule (NAD + to NADH + H + ). In a second step, the catalytic reagent diaphorase transfers the H/H + from NADH + H + to tetrazolium salt (2‐[4‐iodophenyl]‐3‐[4‐nitrophenyl]‐5‐phenyltetrazolium chloride) which it is reduced in formazan salt (Kłósek et al, ).…”

Anti-inflammatory potential of invasive sun corals (Scleractinia: Tubastraea spp.) from Brazil: alternative use for management?

“…With membrane rupture, this enzyme is released into extracellular medium and acts on lactate to oxidative pyruvate reaction, leading to nicotinamide adenine dinucleotide molecule reduction (NAD + for NADH + H + ). In a second step, the catalytic reagent diaphorase transfers the H/H + to tetrazolium salt (2‐[4‐iodophenyl]‐3‐[4‐nitrophenyl]‐5‐phenyltetrazolium chloride) which it has reduced in formazan salt . Fresh cells were added in 96‐well culture plates at 1.0 x 10 4 cells/ml (HepG2 in MEM) and 5.0 x 10 4 cells/ml (RAW 264.7 in DMEM) concentrations, supplemented with 10% FBS.…”

“…In a second step, the catalytic reagent diaphorase transfers the H/H + to tetrazolium salt (2-[4-iodophenyl]-3-[4-nitrophenyl]-5phenyltetrazolium chloride) which it has reduced in formazan salt. [45] Fresh cells were added in 96-well culture plates at 1.0 x 10 4 cells/ml (HepG2 in MEM) and 5.0 x 10 4 cells/ml (RAW 264.7 in DMEM) concentrations, supplemented with 10% FBS. After plating, the culture plates were placed in a 5% CO 2 atmosphere at 37°C for 24 h for cell adhesion.…”