RESUMO
Bone homeostasis is regulated by constant remodeling through osteogenesis by osteoblasts and osteolysis by osteoclasts and osteoporosis can be provoked when this balance is broken. Present pharmaceutical treatments for osteoporosis have harmful side effects and thus, our goal was to develop therapeutics from intrisincally safe natural products. Fucoidan is a polysaccharide extracted from many species of brown seaweed, with valuable pharmaceutical activities. To intensify the effect of fucoidan on bone homeostasis, we hydrolyzed fucoidan using AMG, Pectinex and Viscozyme. Of these, fucoidan biotransformed by Pectinex (Fu/Pec) powerfully inhibited the induction of tartrate-resistant acid phosphatase (TRAP) activity in osteoclasts differentiated from bone marrow macrophages (BMMs) by the receptor for activation of nuclear factor-κB ligand (RANKL). To investigate potential of lower molecular weight fucoidan it was separated into >300 kDa, 50-300 kDa, and <50 kDa Fu/Pec fractions by ultrafiltration system. The effects of these fractions on TRAP and alkaline phosphatase (ALP) activities were then examined in differentiated osteoclasts and MC3T3-E1 osteoblasts, respectively. Interestingly, 50-300 kDa Fu/Pec suppressed RANKL-induced osteoclasts differentiation from BMMs but did not synergistically enhance osteoblasts differentiation induced by osteogenic agents. In addition, this fraction inhibited the expressions of NFATc1, TRAP, OSCAR, and RANK, which are all key transcriptional factors involved in osteoclast differentiation, and those of Src, c-Fos and Mitf, as determined by RT-PCR. In conclusion, enzymatically low-molecularized 50-300 kDa Fu/Pec suppressed TRAP by downregulating RANKL-related signaling, contributing to the inhibition of osteoclasts differentiation, and represented a potential means of inducing bone remodeling in the background of osteoporosis.
Assuntos
Osteoclastos , Osteoporose , Diferenciação Celular , Humanos , Ligantes , NF-kappa B , Fatores de Transcrição NFATC , Osteogênese , Preparações Farmacêuticas , Polissacarídeos , Ligante RANKRESUMO
PURPOSE: We aimed to investigate the effect of metal ions from oral prostheses (OPs) released into the saliva of patients with oral lichenoid lesions (OLLs). MATERIALS AND METHODS: Subjects (n=183) were divided into four groups according to the presence or absence of OLL and OP. Concentrations of the metal ions titanium, chromium (Cr), cobalt (Co), nickel (Ni), palladium (Pd), silver (Ag), platinum (Pt), gold (Au), and zirconium (Zr) were measured using a laser-ablation microprobe inductively coupled to a plasma mass spectrometer. Saliva levels of interleukin (IL)-6, IL-1ß, IL-8, and tumor necrosis factor-α were detected using an enzyme-linked immunosorbent assay. The reticulation/keratosis, erythema, and ulceration (REU) scoring system was used to assess the severity of OLL. RESULTS: Mean concentrations of IL-6 and IL-8 were statistically higher in OLL patients with OPs. The concentration of Ni was high in OLL groups. The concentrations of Cr, Ni, and Au ions in the saliva were positively correlated with IL-8. REU scores were positively correlated with salivary concentrations of IL-6 and IL-8, as well as with concentrations of Cr, Ni, and Au. CONCLUSION: Increased concentrations of metal ions, especially Ni, in saliva were positively correlated with IL-8 and showed positive correlations with the severity of OLL.
Assuntos
Citocinas , Saliva , Ouro , Humanos , Íons , NíquelRESUMO
Macrophages have the potential to re-programing tumor cells in the tumor microenvironments. Thus we investigated anti-cancer effects of M1-polarized macrophages by lipopolysaccharide (LPS) on the physiological properties of human prostate cancer PC-3 cells. To identify communications with immune cells and tumor cells, we performed in-direct way by using conditioned-media (CM) and analyzed tumor properties via quantitative polymerase chain reaction, enzyme-linked immunosorbent assay and western blot and flow cytometry. CM of M1-polarized macrophages induced apoptotic cell death in PC-3 cells, and it surprisingly suppressed tumor parameters including epithelial to mesenchymal transition (EMT), invasion, migration and angiogenesis. EMT specific markers, N-cadherin, snail-1, and TGF ß2 were diminished; however, E-cadherin was increased. In addition, migration markers, vimentin and CCL2 were down-regulated, and finally wound healing was also inhibited. Decreased expression of matrix metalloprotein (MMP)-9 and VEGFA might reduce the invasive and angiogenic abilities of PC-3 cells. These results suggested that co-culture with CM of M1-polarized macrophages showed higher anti-cancer effects on PC-3 cells. Thus, therapeutic targeting of macrophages toward PC-3 cells may represent a useful strategy to complement with the secreted molecules of RAW 264.7 cells as inhibitors of metastasis and anti-cancer agents.
Assuntos
Comunicação Celular/imunologia , Imunoterapia Adotiva/métodos , Macrófagos/imunologia , Neoplasias da Próstata/terapia , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Técnicas de Cocultura , Meios de Cultivo Condicionados , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Humanos , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Camundongos , Invasividade Neoplásica , Células PC-3 , Neoplasias da Próstata/imunologia , Neoplasias da Próstata/patologia , Células RAW 264.7 , Microambiente Tumoral/efeitos dos fármacosRESUMO
The purpose of the present study is to improve the endothelial progenitor cells (EPC) activation, proliferation, and angiogenesis using enzyme-aided extraction of fucoidan by amyloglucosidase (EAEF-AMG). Enzyme-aided extraction of fucoidan by AMG (EAEF-AMG) significantly increased EPC proliferation by reducing the reactive oxygen species (ROS) and decreasing apoptosis. Notably, EAEF-AMG treated EPCs repressed the colocalization of TSC2/LAMP1 and promoted perinuclear localization of mTOR/LAMP1 and mTOR/Rheb. Moreover, EAEF-AMG enhanced EPC functionalities, including tube formation, cell migration, and wound healing via regulation of AKT/Rheb signaling. Our data provided cell priming protocols to enhance therapeutic applications of EPCs using bioactive compounds for the treatment of CVD.
Assuntos
Células Progenitoras Endoteliais/efeitos dos fármacos , Glucana 1,4-alfa-Glucosidase/metabolismo , Polissacarídeos/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Células Progenitoras Endoteliais/metabolismo , Humanos , Proteína 1 de Membrana Associada ao Lisossomo/metabolismo , Neovascularização Fisiológica/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Proteína 2 do Complexo Esclerose Tuberosa/metabolismo , Cicatrização/efeitos dos fármacosRESUMO
Deoxypodophyllotoxin (DPT) is a naturally occurring flavolignan in Anthriscus sylvestris known as cow parsley or wild chervil, and has been reported to have inhibitory effects against several pathological processes including cancer, inflammation and infection. Here, we report the effects of DPT in the fatty liver induced by high fat diet in vivo as well as its regulatory mechanism related with the transcription factor for lipogenic genes such as sterol regulatory element binding protein-1c (SREBP-1c) in vitro. C57BL/6 mice were fed high fat diet for 10 weeks and also orally administrated with DPT for additional 4 weeks. 5 and 10â¯mg/kg of DPT decreased lipid accumulation in the liver induced by high fat diet, as indicated by histological parameters such as Oil Red O staining and hematoxylin & eosin as well as the contents of hepatic triglyceride and cholesterol. In hepatocytes, DPT inhibited the liver X receptor α-mediated SREBP-1c induction and expression of the lipogenic genes, including fatty acid synthase, acetyl-CoA carboxylase and stearoyl-CoA desaturase-1. Moreover, DPT induced AMP-activated protein kinase (AMPK) activation, which has been known to inhibit the expression of SREBP-1c in hepatocyte. Also this compound restored the dysregulation of AMPK and SREBP-1c induced by high fat diet in mice. In conclusion, we demonstrated that DPT significantly inhibited fatty liver by adjusting lipid metabolism coordinated with AMPK activation and SREBP-1c inhibition.
Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Apiaceae/metabolismo , Fígado/efeitos dos fármacos , Podofilotoxina/análogos & derivados , Transdução de Sinais/efeitos dos fármacos , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Animais , Peso Corporal/efeitos dos fármacos , Colesterol/metabolismo , Dieta Hiperlipídica , Medicamentos de Ervas Chinesas , Células Hep G2 , Humanos , Hidrocarbonetos Fluorados/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Receptores X do Fígado/agonistas , Receptores X do Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Podofilotoxina/farmacologia , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Sulfonamidas/farmacologia , Triglicerídeos/metabolismo , Regulação para Cima/efeitos dos fármacosRESUMO
BACKGROUND: A natural compound deoxypodophyllotoxin (DPT) possesses potent anti-proliferative and anti-tumor properties on several cancer types. It triggers cell cycle arrest followed by apoptosis through various cellular processes. However, it is limited to the action mechanism of DPT-mediated cell death modes via apoptosis and autophagy. METHODS: Cell viability assay, morphological changes, annexin-V/propidium iodide (PI) assay, reactive oxygen species (ROS), acridine orange staining, and Western blot analyses were evaluated. RESULTS: We demonstrated that DPT induced both apoptosis and autophagy via production of mitochondrial reactive oxygen species (ROS). DPT suppressed the PI3K/AKT/mTOR signaling cascades to lead autophagy process, resulting from conversion of light chain 3-I (LC3-I) into LC3-II and acidic vesicular organelles (AVOs) formation. Even if DPT-induced ROS were occurred in both apoptosis and autophagy, inhibition of ROS generation enhanced cell viability. Otherwise, 3-methyladeine (3-MA) impeding on autophagy accelerated an apoptotic response caused by DPT. Therefore, these findings suggest that DPT triggers cytoprotective autophagy against cytotoxic apoptosis. CONCLUSION: Autophagy is required for cell survival by inhibition of apoptosis through down-regulation of PI3K/AKT/mTOR pathway against DPT-induced apoptosis in U2OS cells.
Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Osteossarcoma/tratamento farmacológico , Inibidores de Fosfoinositídeo-3 Quinase , Podofilotoxina/análogos & derivados , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Serina-Treonina Quinases TOR/antagonistas & inibidores , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Neoplasias Ósseas/tratamento farmacológico , Linhagem Celular Tumoral , Sobrevivência Celular , Medicamentos de Ervas Chinesas , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Podofilotoxina/farmacologia , Podofilotoxina/uso terapêutico , Espécies Reativas de OxigênioRESUMO
Recently, the interplay between autophagy and apoptosis has become an important factor in chemotherapy for cancer treatment. Inhibition of autophagy may be an effective strategy to improve the treatment of chemo-resistant cancer by consistent exposure to chemotherapeutic drugs. However, no reports have clearly elucidated the underlying mechanisms. Therefore, in this study, we assessed whether salinomycin, a promising anticancer drug, induces apoptosis and elucidated potential antitumor mechanisms in chemo-resistant prostate cancer cells. Cell viability assay, Western blot, annexin V/propidium iodide assay, acridine orange (AO) staining, caspase-3 activity assay, reactive oxygen species (ROS) production, and mitochondrial membrane potential were assayed. Our data showed that salinomycin alters the sensitivity of prostate cancer cells to autophagy. Pretreatment with 3-methyladenine (3-MA), an autophagy inhibitor, enhanced the salinomycin-induced apoptosis. Notably, salinomycin decreased phosphorylated of AKT and phosphorylated mammalian target of rapamycin (mTOR) in prostate cancer cells. Pretreatment with LY294002, an autophagy and PI3K inhibitor, enhanced the salinomycin-induced apoptosis by decreasing the AKT and mTOR activities and suppressing autophagy. However, pretreatment with PD98059 and SB203580, an extracellular signal-regulated kinases (ERK), and p38 inhibitors, suppressed the salinomycin-induced autophagy by reversing the upregulation of ERK and p38. In addition, pretreatment with N-acetyl-l-cysteine (NAC), an antioxidant, inhibited salinomycin-induced autophagy by suppressing ROS production. Our results suggested that salinomycin induces apoptosis, which was related to ROS-mediated autophagy through regulation of the PI3K/AKT/mTOR and ERK/p38 MAPK signaling pathways.
Assuntos
Autofagia/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Piranos/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , Flavonoides/farmacologia , Humanos , Imidazóis/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Inibidores de Fosfoinositídeo-3 Quinase , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/metabolismo , Piridinas/farmacologia , Serina-Treonina Quinases TOR/antagonistas & inibidores , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidoresRESUMO
Salinomycin is a polyether ionophore antibiotic that has recently been shown to induce cell apoptosis in human cancer cells displaying multiple mechanisms of drug resistance. In the present study, we explored the impact of salinomycin on the apoptosis and autophagy as well as the correlation between those effects and endoplasmic reticulum (ER) stress molecular mechanisms in human glioma U87MG cells. Apoptosis, autophagy and reactive oxygen species (ROS) were analyzed using flow cytometry. In addition, expression levels of apoptosis-, autophagy- and ER stress-related proteins were determined by western blotting. The results showed that salinomycin induced apoptosis, ER stress and autophagy in glioma cancer cell lines. In addition, salinomycin also induced ROS generation, and the ROS scavenger N-acetyl-L-cysteine was found to inhibit the salinomycin-induced apoptosis, ER stress and autophagy. The inhibition of ER stress with 4-phenylbutyric acid depressed salinomycin-induced apoptosis and autophagy. Salinomycin increased the expression of autophagy marker protein, LC3B, and accumulation of acidic vesicular organelles. Furthermore, pre-treatment with the autophagy inhibitor 3-methyladenine showed potential in increasing the apoptosis rate induced by salinomycin in the U87MG cells. Taken together, these results revealed that salinomycin induced apoptosis and autophagy via ER stress mediated by ROS, suggesting that ER stress by salinomycin plays a dual function in both promoting and suppressing cell death.
Assuntos
Autofagia/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Glioma/tratamento farmacológico , Piranos/administração & dosagem , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Retículo Endoplasmático/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Glioma/genética , Glioma/patologia , Humanos , Espécies Reativas de Oxigênio/metabolismoRESUMO
BACKGROUND/AIM: Chemotherapy is a critical option for cancer treatment. However, consistent exposure to chemotherapeutic drugs promotes chemoresistance in cancer cells through diverse mechanisms. Accordingly, we investigated whether salinomycin, a monocarboxylic ionophore, could induce apoptosis in aggressive breast cancer cells or not, as well as its underlying mechanism. MATERIALS AND METHODS: Using salinomycin on two breast cancer cell lines, MCF-7 cells and MDA-MB-231 cells, cell viability, annexin V/propidium iodide staining, acridine orange staining, caspase-3/9 activity, reactive oxygen species (ROS) and mitochondrial membrane potential (MMP) were assayed. RESULTS: In this study, salinomycin induced apoptosis and autophagy in MDA-MB-231 cells. Salinomycin-mediated ROS production led to mitochondrial dysfunction in MDA-MB-231 cells. Interestingly, treatment of N-acetyl-L-cysteine (NAC), a scavenger of ROS, attenuated salinomycin-induced apoptosis and autophagy. Moreover, autophagy inhibition is involved in acceleration of apoptosis induced by salinomycin. CONCLUSION: Salinomycin induced apoptosis and ROS production, that were blocked by autophagy, thus resulting in protecting cancer cells. This crosstalk of two different physiological responses (autophagy and apoptosis) induced by salinomycin might play pivotal roles in the relationship between autophagy and apoptosis of cancer cells.
Assuntos
Antibacterianos/farmacologia , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Neoplasias da Mama/patologia , Piranos/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Western Blotting , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Proliferação de Células/efeitos dos fármacos , Feminino , Imunofluorescência , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Células Tumorais CultivadasRESUMO
Lasalocid is an antibiotic from the group of carboxylic ionophores, produced by Streptomyces lasaliensis. But there was limited information of lasalocid on human prostate cancer cells. In the present studies, to better understand its effect in human prostate cancer cells, apoptosis and autophagy associated with possible signal pathways in vitro was examined. Our study showed that lasalocid mediated cell cycle arrest in G0/G1 phase by reducing G1 phase dependent proteins, indicating entering into apoptotic cell death pathway. Lasalocid-induced apoptosis was involved with reactive oxygen species (ROS) production, and mitochondrial hyperpolarization. In addition, lasalocid induced autophagy through microtubule-associated protein 1 light chain 3 (LC-3)-II conversion, acidic vesicular organelles formation and GFP-LC-3 punctuate, which was inhibited by 3-methyladenine (3-MA), a widely used pharmacological inhibitor of autophagy. Furthermore, the autophagic phenomena were mediated by production of ROS, confirming that inhibition of ROS with N-acetyl-l-cysteine, a ROS inhibitor, attenuated lasalocid-triggered autophagy. Inhibition of autophagy with 3-MA enhanced the lasalocid-induced apoptosis through enhanced ROS generation. Taken together, lasalocid should be useful in the search for new potential chemotherapeutic agents for understanding the molecular mechanisms of anticancer in prostate cancer cells.
Assuntos
Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Lasalocida/farmacologia , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Espécies Reativas de Oxigênio/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Humanos , MasculinoRESUMO
BACKGROUND: Toyocamycin, an antibiotic agent isolated from Streptomyces species, has been shown to have anticancer and chemopreventive effects on various cancer cells. Until now, Toyocamycin-induced apoptosis has not been reported to be involved in the regulation between mitogen-activated protein kinases (MAPKs) and reactive oxygen species (ROS) production. METHODS: Cell viability assay, western blot, cell-cycle arrest, annexin V/propidium iodide assay, reactive oxygen species (ROS) production, mitochondrial membrane potential and intracellular Ca2+ flux were assayed. RESULTS: We investigated the apoptotic effect of Toyocamycin and the underlying molecular mechanism in prostate cancer PC-3 cells. Toyocamycin treatment resulted in reduced cell viability of PC-3 cells, but not of non-malignant RWPE-1 cells. Toyocamycin enhanced apoptosis, mitochondrial dysfunction, and ROS production in PC-3 cells. In addition, MAPK proteins were activated upon Toyocamycin treatment. The p38 and extracellular signal-regulated kinases (ERK) activities were regulated by ROS-mediated signaling pathway underlying the Toyocamycin-induced apoptosis. Pretreatment with N-acetyl-l-cysteine (NAC) recovered the Toyocamycin-induced mitochondrial dysfunction, ROS, and apoptosis. Additionally, p38 stimulated ROS production and inhibitory effects on ERK activation, while ERK inhibited the ROS production and had no effect on p38 activation. CONCLUSION: ROS-mediated activation of p38/ERK partially contributes to Toyocamycin-induced apoptosis, and p38/ERK MAPKs regulate the ROS production in PC-3 cells.
Assuntos
Apoptose/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Neoplasias da Próstata/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Toiocamicina/farmacologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Apoptose/fisiologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Relação Dose-Resposta a Droga , Humanos , MasculinoRESUMO
Deoxypodophyllotoxin (DPT) is a naturally occurring flavolignan isolated from Anthriscus sylvestris. Recently, it has been reported that DPT inhibits tubulin polymerization and induces G2/M cell cycle arrest followed by apoptosis through multiple cellular processes. Despite these findings, details regarding the cellular and molecular mechanisms underlying the DPT-mediated cell death have been poorly understood. To define a mechanism of DPT-mediated cell death response, we examined whether DPT activates signaling pathways for autophagy and apoptosis. We demonstrated that DPT inhibited cell viability and induced apoptosis in prostate cancer cell lines, as evidenced by a mitochondrial membrane potential and expression of apoptosis-related proteins. Reactive oxygen species (ROS), primarily generated from the mitochondria, play an important role in various cellular responses, such as apoptosis and autophagy. DPT significantly triggered mitochondrial ROS, which were detected by MitoSOX, a selective fluorescent dye of mitochondria-derived ROS. Furthermore, DPT induced autophagy through an up-regulation of autophagic biomarkers, including a conversion of microtubule-associated protein 1 light chain 3 - I (LC3-I) into LC3-II and a formation of acidic vesicular organelles. Moreover, mitochondrial ROS promoted AKT-independent autophagy and ERK signaling. The inhibition of autophagy with 3-methyladenine or LC3 knockdown enhanced DPT-induced apoptosis, suggesting that an autophagy plays a protective role in cell survival against apoptotic prostate cancer cells. Additionally, the results from an in vivo xenograft model confirmed that DPT inhibited tumor growth by regulating the apoptosis- and autophagy-related proteins.
RESUMO
BACKGROUND: Monensin is a carboxyl polyether ionophore that potently inhibits the growth of various cancer cells. Recently, the anticancer effects of monensin have been recognized based on its ability to induce apoptosis in cancer cells. However, anticancer effect of monensin and its mechanism of action have yet to be investigated, especially against human prostate cancer cells. MATERIALS AND METHODS: Cell viability assay, western blot, cell-cycle arrest, annexin V/propidium iodide assay, reactive oxygen species (ROS) production and intracellular Ca2+ flux were assayed. RESULTS: In this study, monensin significantly inhibited cell viability in a dose-dependent manner in prostate cell lines. Moreover, cell growth inhibition by monensin induced G1 phase cell-cycle arrest and apoptosis via regulation of cell cycle- and apoptosis-related proteins in PC-3 cells. In addition, monensin induced the production of ROS and the disruption of Ca2+ homeostasis, that was restored by diphenyleneiodonium, a mitochondrial ROS inhibitor and verapamil, a Ca2+ channel blocker, respectively, as confirmed by pro-caspase-3 activation and poly ADP ribose polymerase cleavage. CONCLUSION: Monensin induces cell-cycle arrest and apoptosis through regulation of cell cycle- and apoptosis-related proteins, resulting in induction of mitochondrial ROS- and Ca2+-dependent apoptosis, respectively.
Assuntos
Apoptose/efeitos dos fármacos , Cálcio/metabolismo , Homeostase/efeitos dos fármacos , Monensin/farmacologia , Neoplasias da Próstata/patologia , Espécies Reativas de Oxigênio/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Masculino , Neoplasias da Próstata/metabolismoRESUMO
BACKGROUND: Silibinin, a biologically active compound of milk thistle, has chemopreventive effects on cancer cell lines. Recently it was reported that silibinin inhibited tumor growth through activation of the apoptotic signaling pathway. Although various evidences showed multiple signaling pathways of silibinin in apoptosis, there were no reports to address the clear mechanism of ROS-mediated pathway in prostate cancer PC-3 cells. Several studies suggested that reactive oxygen species (ROS) play an important role in various signaling cascades, but the primary source of ROS was currently unclear. METHODS: The effect of silibinin was investigated on cell growth of prostate cell lines by MTT assay. We examined whether silibinin induced apoptosis through production of ROS using flow cytometry. Expression of apoptosis-, endoplasmic reticulum (ER)-related protein and gene were determined by western blotting and RT-PCR, respectively. RESULTS: Results showed that silibinin triggered mitochondrial ROS production through NOX4 expression and finally led to induce apoptosis. In addition, mitochondrial ROS caused ER stress through disruption of Ca(2+) homeostasis. Co-treatment of ROS inhibitor reduced the silibinin-induced apoptosis through the inhibition of NOX4 expression, resulting in reduction of both Ca(2+) level and ER stress response. CONCLUSIONS: Taken together, silibinin induced mitochondrial ROS-dependent apoptosis through NOX4, which is associated with disruption of Ca(2+) homeostasis and ER stress response. Therefore, the regulation of NOX4, mitochondrial ROS producer, could be a potential target for the treatment of prostate cancer.
Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , NADPH Oxidases/metabolismo , Neoplasias da Próstata/tratamento farmacológico , Silimarina/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Retículo Endoplasmático/fisiologia , Humanos , Masculino , Mitocôndrias/metabolismo , NADPH Oxidase 4 , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , SilibinaRESUMO
Salinomycin, a polyether antibiotic, acts as a highly selective potassium ionophore. It was reported to anticancer activity on various cancer cell lines. In this study, salinomycin was examined on apoptosis and autophagy through generation of reactive oxygen species (ROS) in osteosarcoma U2OS cells. Apoptosis, autophagy, mitochondrial membrane potential (MMP) and ROS were analyzed using flow cytometry. Also, expressions of apoptosis- and autophagy-related proteins were determined by western blotting. As a result, salinomycin triggered apoptosis of U2OS cells, which was accompanied by change of MMP and cleavage of caspases-3 and poly (ADP-ribose) polymerase. And salinomycin increased the expression of autophagy-related protein and accumulation of acidic vesicular organelles (AVO). Salinomycin-induced ROS production promotes both apoptosis and autophagy, as evidenced by the result that treatment of N-acetyl-l-cysteine (NAC), a ROS scavenger, attenuated both apoptosis and autophagy. In addition, inhibition of autophagy by 3-methyladenine (3 MA) enhanced the salinoymcin-induced apoptosis. Taken together, these results suggested that salinomycin-induced autophagy, as a survival mechanism, might be a potential strategy through ROS regulation in cancer therapy.
Assuntos
Antibióticos Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Neoplasias Ósseas/tratamento farmacológico , Osteossarcoma/tratamento farmacológico , Piranos/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Neoplasias Ósseas/patologia , Linhagem Celular Tumoral , Humanos , Ionóforos/farmacologia , Osteossarcoma/patologiaRESUMO
Silibinin is a major bioactive component of silymarin and has anticancer effects on cancer cell line and has been used as a supportive therapy for chronic inflammatory liver condition. These anticancer effects of silibinin have been demonstrated both in vitro and in vivo cancer models. Although various evidences showed apoptosis signaling pathways by silibinin, there is no report to address the clearly mechanism of silibinin-induced autophagy in prostate cancer PC-3 cells. Our study showed that silibinin triggered autophagy through up-regulation of microtubule-associated protein 1 light chain 3 (LC3)-II, formation of acidic vesicular organelles (AVO) and punctuate of GFP-LC3, which was inhibited by 3-methyladenine (3-MA), an inhibitor of specific autophagy. In addition, silibinin induced autophagy through production of reactive oxygen species (ROS). Inhibition of ROS with diphenyleneiodonium (DPI), a ROS inhibitor, attenuated silibinin-triggered autophagy. Inhibition of autophagy with 3-MA enhanced the silibinin-induced apoptosis through the regulation of caspase-3 and PARP. These results suggested that silibinin induced autophagy by regulating ROS and its mechanism played a protective role against apoptosis in PC-3 cells.
Assuntos
Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Próstata/efeitos dos fármacos , Neoplasias da Próstata/tratamento farmacológico , Espécies Reativas de Oxigênio/metabolismo , Silimarina/farmacologia , Autofagia/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Masculino , Proteínas Associadas aos Microtúbulos/metabolismo , Silybum marianum/química , Próstata/metabolismo , Próstata/patologia , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , SilibinaRESUMO
Salinomycin is a monocarboxylic polyether antibiotic, which is widely used as an anticoccidial agent. The anticancer property of salinomycin has been recognized and is based on its ability to induce apoptosis in human multidrug resistance (MDR). The present study investigated whether salinomycin reverses MDR towards chemotherapeutic agents in doxorubicin-resistant MCF-7/MDR human breast cancer cells. The results demonstrated that doxorubicin-mediated cytotoxicity was significantly enhanced by salinomycin in the MCF-7/MDR cells, and this occurred in a dose-dependent manner. This finding was consistent with subsequent observations made under a confocal microscope, in which the doxorubicin fluorescence signals of the salinomycin-treated cells were higher compared with the cells treated with doxorubicin alone. In addition, flow cytometric analysis revealed that salinomycin significantly increased the net cellular uptake and decreased the efflux of doxorubicin. The expression levels of MDR-1 and MRP-1 were not altered at either the mRNA or protein levels in the cells treated with salinomycin. These results indicated that salinomycin was mediated by its ability to increase the uptake and decrease the efflux of doxorubicin in MCF-7/MDR cells. Salinomycin reversed the resistance of doxorubicin, suggesting that chemotherapy in combination with salinomycin may benefit MDR cancer therapy.
Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Doxorrubicina/farmacologia , Piranos/farmacologia , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Células MCF-7 , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismoRESUMO
The antiproliferation effects of pipernonaline, a piperine derivative, were investigated on human prostate cancer PC-3 cells. It inhibited growth of androgen independent PC-3 and androgen dependent LNCaP prostate cells in a dose-dependent (30-90 µM) and time-dependent (24-48 h) manner. The growth inhibition of PC-3 cells was associated with sub-G(1) and G(0)/G(1) accumulation, confirmed by the down-regulation of CDK2, CDK4, cyclin D1 and cyclin E, which are correlated with G(1) phase of cell cycle. Pipernonaline up-regulated cleavage of procaspase-3/PARP, but did not change expression of proapoptotic bax and antiapoptotic bcl-2 proteins. Its caspase-3 activation was confirmed by the caspase-3 assay kit. In addition, pipernonaline caused the production of reactive oxygen species (ROS), increase of intracellular Ca(2+), and mitochondrial membrane depolarization, which these phenomena were reversed by N-acetylcysteine, a ROS scavenger. The results suggest that pipernonaline exhibits apoptotic properties through ROS production, which causes disruption of mitochondrial function and Ca(2+) homeostasis and leads to its downstream events including activation of caspase-3 and cleavage of PARP in PC-3 cells. This is the first report of pipernonaline toward the anticancer activity of prostate cancer cells, which provides a role for candidate agent as well as the molecular basis for human prostate cancer.
Assuntos
Alcaloides/farmacologia , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Piper/química , Piperidinas/farmacologia , Neoplasias da Próstata/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Alcaloides/química , Antineoplásicos/química , Caspase 3/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Humanos , Masculino , Piperidinas/química , Poli(ADP-Ribose) Polimerases/metabolismo , Neoplasias da Próstata/patologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Fase de Repouso do Ciclo Celular/efeitos dos fármacosRESUMO
The limited treatment option for recurrent prostate cancer and the eventual resistance to conventional chemotherapy drugs has fueled continued interest in finding new anti-neoplastic agents of natural product origin. We previously reported anti-proliferative activity of deoxypodophyllotoxin (DPT) on human prostate cancer cells. Using the PC-3 cell model of human prostate cancer, the present study reveals that DPT induced apoptosis via a caspase-3-dependent pathway that is activated due to dysregulated mitochondrial function. DPT-treated cells showed accumulation of the reactive oxygen species (ROS), intracellular Ca (i)(2+) surge, increased mitochondrial membrane potential (MMP, ΔΨ(m)), Bax protein translocation to mitochondria and cytochrome c release to the cytoplasm. This resulted in caspase-3 activation, which in turn induced apoptosis. The antioxidant N-acetylcysteine (NAC) reduced ROS accumulation, MMP and Ca (i)(2+) surge, on the other hand the Ca(2+) chelator BAPTA inhibited the Ca( i)(2+) overload and MMP without affecting the increase of ROS, indicating that the generation of ROS occurred prior to Ca(2+) flux. This suggested that both ROS and Ca( i)(2+) signaling play roles in the increased MMP via Ca (i)(2+)-dependent and/or -independent mechanisms, since ΔΨ(m) elevation was reversed by NAC and BAPTA. This study provides the first evidence for the involvement of both ROS- and Ca( i)(2+)-activated signals in the disruption of mitochondrial homeostasis and the precedence of ROS production over the failure of Ca(2+) flux homeostasis.
Assuntos
Apoptose/efeitos dos fármacos , Cálcio/metabolismo , Homeostase/efeitos dos fármacos , Mitocôndrias/metabolismo , Podofilotoxina/análogos & derivados , Neoplasias da Próstata/patologia , Espécies Reativas de Oxigênio/metabolismo , Caspase 3/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Citocromos c/metabolismo , Ensaios de Seleção de Medicamentos Antitumorais , Medicamentos de Ervas Chinesas , Ácido Egtázico/análogos & derivados , Ácido Egtázico/farmacologia , Ativação Enzimática/efeitos dos fármacos , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Humanos , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , Pontos de Checagem da Fase M do Ciclo Celular/efeitos dos fármacos , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Modelos Biológicos , Podofilotoxina/química , Podofilotoxina/farmacologia , Neoplasias da Próstata/metabolismo , Transporte Proteico/efeitos dos fármacos , Proteína X Associada a bcl-2/metabolismoRESUMO
The anticancer activity of salinomycin has evoked excitement due to its recent identification as a selective inhibitor of breast cancer stem cells (CSCs) and its ability to reduce tumor growth and metastasis in vivo. In prostate cancer, similar to other cancer types, CSCs and/or progenitor cancer cells are believed to drive tumor recurrence and tumor growth. Thus salinomycin can potentially interfere with the end-stage progression of hormone-indifferent and chemotherapy-resistant prostate cancer. Androgen-responsive (LNCaP) and androgen-refractive (PC-3, DU-145) human prostate cancer cells showed dose- and time-dependent reduced viability upon salinomycin treatment; non-malignant RWPE-1 prostate cells were relatively less sensitive to drug-induced lethality. Salinomycin triggered apoptosis of PC-3 cells by elevating the intracellular ROS level, which was accompanied by decreased mitochondrial membrane potential, translocation of Bax protein to mitochondria, cytochrome c release to the cytoplasm, activation of the caspase-3 and cleavage of PARP-1, a caspase-3 substrate. Expression of the survival protein Bcl-2 declined. Pretreatment of PC-3 cells with the antioxidant N-acetylcysteine prevented escalation of oxidative stress, dissipation of the membrane polarity of mitochondria and changes in downstream molecular events. These results are the first to link elevated oxidative stress and mitochondrial membrane depolarization to salinomycin-mediated apoptosis of prostate cancer cells.