Exploring the anticancer effects of tin oxide nanoparticles synthesized by pulsed laser ablation technique against breast cancer cell line through downregulation of PI3K/AKT/mTOR signaling pathway

Tin oxide nanoparticles (SnO₂ NPs) demonstrate potential anti-cancer functions. However, the anti-cancer mechanisms of SnO₂ NPs have not been explored in detail. In the present study, we synthesized SnO₂ NPs through laser ablation technique and examined their anticancer mechanisms and the probable involvement of the PI3K/AKT mediated pathways in human breast cancer cells (MCF-7) in vitro. The synthesized SnO₂ NPs were characterized by transmission electron microcopy (TEM), dynamic light scattering (DLS), and Fourier-transform infrared spectroscopy (FTIR) techniques. Afterwards, the breast cancer cells were incubated with increasing concentrations of SnO₂ NPs, and inhibition of cell proliferation was assessed by the viability assay. Furthermore, the quantification of reactive oxygen species (ROS) and apoptosis were examined by flow cytometry followed by superoxide dismutase (SOD) and catalase (CAT) activity as well as mitochondrial membrane potential assays. The expression levels of phosphoinositide 3-kinase (PI3K), protein kinase B (AKT), mechanistic target of rapamycin (mTOR), B-cell lymphoma 2 (Bcl-2), and Bax were also assessed by western blot and quantitative real time PCR (qRT-PCR). It was shown that SnO₂ NPs, 30 nm, with potential colloidal stability selectively prevented the proliferation of MCF-7 in comparison with MCF-10A cells and triggered ROS production, apoptosis, deactivation of SOD and CAT activity, and mitigation of mitochondrial membrane potential. Moreover, SnO₂ NPs stimulated mitochondrial-mediated apoptosis pathway by overexpression of Bax/Bcl-2 and downregulation of p-PI3K/p-AKT/p-mTOR signaling pathway. This data elucidates the possible mechanisms by which SnO₂ NPs may stimulate their anticancer effects.     

Dioscorealide B from the traditional Thai medicine Hua-Khao-Yen induces apoptosis in MCF-7 human breast cancer cells via modulation of Bax, Bak and Bcl-2 protein expression

Dioscorealide B is a pharmacologically active compound from the rhizome of the Thai medicinal plant Dioscorea membranacea. Here, we demonstrated that in vitro treatment of dioscorealide B resulted in a cytotoxic effect on MCF-7 human breast cancer cells (IC50 = 2.82 microM). To determine whether this compound induces apoptosis in MCF-7, the Annexin V assay was performed. The data showed that the number of apoptotic cells were increased 7-12 folds over that of the control cells after treatment with various concentrations of dioscorealide B (3, 6 and 12 microM) for 24 hours. Dioscorealide B-induced apoptosis was associated with modulation of the multidomain Bcl-2 family members Bax, Bak and Bcl-2. After treatment with 3 microM dioscorealide B, acceleration of the level of proapoptotic proteins Bax and Bak were observed at 6 hours and 12 hours, respectively, while the decrease in the expression of antiapoptotic protein Bcl-2 was observed 3 hours after the treatment. These effects of dioscorealide B might result in the activation of caspase-8, -9 and -7, which lead to apoptosis in MCF-7 cells. Taken together, the results of this study provide evidence that dioscorealide B possesses an antitumor property against human breast cancer cells and thus provide the molecular basis for the further development of dioscorealide B as a novel chemotherapeutic agent for breast cancer treatment.     

Down-regulation of Bcl-2 and Akt induced by combination of photoactivated hypericin and genistein in human breast cancer cells

Presented experiment considers combination of genistein and photodynamic therapy with hypericin with a view to achieve higher therapeutic outcome in human breast adenocarcinoma cell lines MCF-7 and MDA-MB-231, both identified in our conditions as photodynamic therapy resistant. Since genistein is known to suppress Bcl-2 expression, we predicted that photodynamic therapy with hypericin might benefit from mutual therapeutic combination. In line with our expectations, combined treatment led to down-regulation of Bcl-2 and up-regulation of Bax in both cell lines as well as to suppression of Akt and Erk1/2 phosphorylation induced by photoactivated hypericin in MCF-7 cells. Although Akt and Erk1/2 phosphorylation was not stimulated by photodynamic therapy with hypericin in MDA-MB-231 cells, it was effectively suppressed in combination. Variations in cell death signaling favoring apoptosis were indeed accompanied by cell cycle arrest in G₂/M-phase, activation of caspase-7, PARP cleavage and increased occurrence of cells with apoptotic morphology of nucleus. All these events corresponded with suppression of proliferation and significantly lowered clonogenic ability of treated cells. In conclusion, our results indicate that pre-treatment with tyrosine kinase inhibitor genistein may significantly improve the effectiveness of photodynamic therapy with hypericin in MCF-7 and MDA-MB-231 breast cancer cells.     

Synthesis,characterization and biological evaluation of some novel sulfonylthiosemicarbazides

Abstract

A series of thiosemicarbazides were synthesized and structurally characterized by spectroscopic techniques (NMR, FT-IR) besides elemental analysis. These compounds were evaluated for their cytotoxicity against human breast cancer cell line MCF7 and prostate cancer cell line PC3 and nonmalignant fibroblast L929 cell line by MTT assay. Among the compounds, N-[2-(4-chlorophenyl)ethyl]-2-[(4-methylphenyl)sulfonyl]hydrazinecarbothioamide (3d) and 2-[(4-methylphenyl)sulfonyl]-N-[4-(trifluoromethoxy)phenyl]hydrazinecarbothioamide (3f) were found to display significant cytotoxicity with IC₅₀ of 13.87?μM (against PC3 cell line) and 1.47?μM (against MCF7 cell line), respectively. These compounds were non-cytotoxic to normal cell line with IC₅₀>100?μM. Western blotting studies demonstrated that compound 3f induced apoptosis and caused cell death in the MCF7 and PC3 cell lines via an increase in Bax protein expression and a slight decrease in Bcl-2 protein expression. The gene expression ratio Bax/Bcl-2 showed the induction of mitochondrial apoptosis in cancer cell lines. All of synthesized compounds have also been tested for antioxidant activity and all compounds achieved strong inhibition of the DPPH radical. These findings showed that compound 3f, displays potential to be further explored in the development of new anticancer agents.     

Prisconnatanones A,a cytotoxic naphthoquinone from Prismatomeris connata,suppresses the proliferation of human laryngocarcinoma HEp-2 cells in vitro

Prisconnatanones A (Priscon-A) is a rare tetrahydroanthraquinone isolated from herbal Prismatomeris connate. In this study, we examine its anti-tumour activity on human laryngocarcinoma HEp-2 cells in vitro. The CCK-8 assay was performed to evaluate its cytotoxicity. Cell cycle and apoptosis were analysed using flow cytometric analysis. Here, we showed Priscon-A inhibited the proliferation of HEp-2 cells in a dose-dependent manner, and at 5 μM it almost completely inhibited cell growth. Its cytotoxicity was associated with the cell cycle arrest at G2/M phase. The Annexin V-FITC/PI binding assay showed that the cell death induced by Priscon-A was associated with apoptosis. And, western blot analysis revealed that the levels of the apoptosis protein, cleaved caspase-3, PARP, p21 and Bax protein increased, while the level of anti-apoptosis protein Bcl-2 decreased.. These data demonstrated that Priscon-A significantly inhibited HEp-2 cell growth, induced the cell cycle arrest at the G2/M phase and efficiently induced cell apoptosis.     

Design and Synthesis of Novel Betulin Derivatives Containing Thio-/Semicarbazone Moieties as Apoptotic Inducers through Mitochindria-Related Pathways

Two new series of betulin derivatives with semicarbazone (7a–g) or thiosemicarbazone (8a–g) groups at the C-28 position were synthesized. All compounds were evaluated for their in vitro cytotoxicities in human hepatocellular carcinoma cells (HepG2), human breast carcinoma cells (MCF-7), human lung carcinoma cells (A549), human colorectal cells (HCT-116) and normal human gastric epithelial cells (GES-1). Among these compounds, 8f displayed the most potent cytotoxicity with an IC₅₀ value of 5.86 ± 0.61 μM against MCF-7 cells. Furthermore, the preliminary mechanism studies in MCF-7 cells showed that compound 8f could trigger the intracellular mitochondrial-mediated apoptosis pathway by losing MMP level, which was related with the upregulation of Bax, P53 and cytochrome c expression; the downregulation of Bcl-2 expression; activation of the expression levels of caspase-3, caspase-9, cleaved caspase-3 and cleaved caspase-9; and an increase in the amounts of intracellular reactive oxygen species. These results indicated that compound 8f may be used as a valuable skeleton structure for developing novel antitumor agents.     

Cytotoxicity of Mahanimbine from Curry Leaves in Human Breast Cancer Cells (MCF-7) via Mitochondrial Apoptosis and Anti-Angiogenesis

Mahanimbine (MN) is a carbazole alkaloid present in the leaves of Murraya koenigii, which is an integral part of medicinal and culinary practices in Asia. In the present study, the anticancer, apoptotic and anti-invasive potential of MN has been delineated in vitro. Apoptosis cells determination was carried out utilizing the acridine orange/propidium iodide double fluorescence test. During treatment, caspase-3/7,-8, and-9 enzymes and mitochondrial membrane potentials (Δψm) were evaluated. Anti-invasive properties were tested utilizing a wound-healing scratch test. Protein and gene expression studies were used to measure Bax, Bcl2, MMP-2, and -9 levels. The results show that MN could induce apoptosis in MCF-7 cells at 14 µM concentration IC₅₀. MN-induced mitochondria-mediated apoptosis, with loss in Δψm, regulation of Bcl2/Bax, and accumulation of ROS (p ≤ 0.05). Caspase-3/7 and -9 enzyme activity were detected in MCF-7 cells after 24 and 48 h of treatment with MN. The anti-invasive property of MN was shown by inhibition of wound healing at the dose-dependent level and significantly suppressed mRNA and protein expression on MMP-2 and -9 in MCF-7 cells treated with a sub-cytotoxic dose of MN. The overall results indicate MN is a potential therapeutic compound against breast cancer as an apoptosis inducer and anti-invasive agent.     

The Role of ΔFosB on the Pro-survival Effect of PTHrP in Goat Mammary Epithelial Cells

The mechanism of regulation mammary epithelial cell number in ruminant is not fully understood, but is thought to be dependent on the balance of cell proliferation and cell apoptosis. Parathyroid hormone-related protein (PTHrP) could express in mammary epithelial cells and breast cancer cells, and has been reported to regulate cell survival. Here, we showed that PTHrP induced cell proliferation and increased the expression of CyclinD1 and proliferating cell nuclear antigen (PCNA) in goat mammary epithelial cells (GMEC). PTHrP increased the mRNA levels of anti-apoptosis genes Bcl-2 and Bcl-xl, and protected GMEC from apoptosis. We also found ΔFosB, an alternative splicing of finkel-biskis-jinkins murine osteosarcoma B (fosB), inhibited GMEC apoptosis, and induced cell proliferation with increased Bcl-2/Bax and Bcl-xl/Bax ratios. Interestingly, ΔFosB could further promote the pro-survival effect of PTHrP, and the Bcl-2/Bax and Bcl-xl/Bax ratios showed higher levels. We conclude that the pro-survival role of PTHrP in GMEC may be regulated by ΔFosB.     

Novel 2,5-disubstituted-1,3,4-oxadiazole derivatives induce apoptosis in HepG2 cells through p53 mediated intrinsic pathway

A series of novel 1,3,4-oxadiazole derivatives (OSD, OCOD, ONOD, OPD, COD, PMOD, and PCOD) were synthesized and characterized. Their structures were confirmed on the basis of IR, NMR and mass spectroscopy and molecular weights were found in the range 300–325 g/mol. Cancerous cell lines (MCF-7, HepG2) and non-cancerous cell lines (Chang liver cells) were treated with these compounds for 48 h, which caused dose dependent decrease in the cell viability. From the seven derivatives, OSD was found to be most potent with IC₅₀ value close to 50 μM on all tested cell lines. Hence, this compound was selected for mechanistic study on HepG2 cell lines. Fluorescent cell staining and DNA fragmentation study of 50 μM OSD on HepG2 cells, showed events marked by apoptosis such as nuclear fragmentation, cytoplasm shrinkage and DNA damage. Further, the cells with same treatment were quantified for apoptosis using annexin V-PI flow cytometric technique. The percentage of apoptotic cells was significantly higher (p < 0.05) after OSD treatment compared to control cells. OSD induced a significant increase (p < 0.05) in the expression of the tumor suppressor p53 in HepG2 cells. The constitutive expression of anti-apoptotic protein Bcl-2 significantly decreased (p < 0.05) after treatment, while the expression of proapoptotic protein Bax significantly increased (p < 0.05). The change in Bax to Bcl-2 ratio suggested involvement of Bcl-2 family in induction of apoptosis. Furthermore, the levels of caspase-9 and caspase-3 were significantly (p < 0.05) up regulated in HepG2 cells after OSD treatment. The data suggest that 1,3,4-oxadiazole derivatives induce apoptosis mediated by intrinsic pathway of apoptosis. The findings strengthen the potential of the 1,3,4-oxadiazole scaffold OSD, as an agent with chemotherapeutic and cytostatic activity in human hepatocellular carcinoma in vitro.     

New salen-type manganese(III) Schiff base complexes derived from meso-1,2-diphenyl-1,2-ethylenediamine: In vitro anticancer activity,mechanism of action,and molecular docking studies

Four new manganese(III) Schiff base complexes (1–4) were synthesized and characterized. The complexes have general formula [MnClL^x] in which L represents a Schiff base ligand derived from condensation of meso-1,2-diphenyl-1,2-ethylenediamine with salicylaldehyde or its 3-OMe-, 5-Br-, or 5-OMe-derivatives (x = 1–4, respectively). The crystal structure of [MnClL¹] (1) was characterized by X-ray crystallography. The in vitro anticancer activity of these complexes was evaluated by MTT and apoptosis assays against human breast (MCF-7) and liver (Hep G2) cancer cells. The complexes exhibited considerable antiproliferative activity against both cell lines (IC₅₀ = 10.8–21.02 μM) comparable to cis-platin, except 4 (MCF-7). The highest activity was found for 1 with IC₅₀ values of 13.62 μM (MCF-7) and 10.8 μM (Hep G2). Flow cytometry experiments showed that 1 induced apoptosis on MCF-7 tumor cell line. Docking simulations using AUTODOCK were also carried out. The results showed that all complexes fitted into the minor groove region of DNA.     

Apoptogenic effects of β-sitosterol glucoside from Castanopsis indica leaves

β-Sitosterol glucoside (BSSG) is a natural biologically active substance isolated from the Castanopsis indica leaves. This study explored the apoptogenic mechanistic studies of BSSG against Ehrlich's ascites carcinoma (EAC) treated mice through morphological study, comet assay, flow cytometry (FACS) and Western blotting assay method. AO/EB staining and FACS analysis showed that BSSG possessed apoptosis induction activities on EAC cells. Dose dependent induction of DNA damage was observed after BSSG treatment. Increase the expression of apoptotic protein p53 and p21 in EAC, multiple downstream factors contributing to apoptosis pathway. The increase of caspase-9 and caspase-3 activities revealed that caspase was a key mediator of the apoptotic pathway induced by BSSG, and up-regulation of Bax and down-regulation of anti-apoptotic protein Bcl-2 resulted in the decrease of Bcl-2/Bax ratio. Owing to the combination of significant antitumour activity by inducing apoptosis, BSSG holds the promise of being an interesting chemo-preventive agent active in cancer therapy.     

Silver–palm pollen nanocomposite exhibits antiproliferative,antioxidant, and proapoptotic properties on MCF-7 breast cancer cells

The aim of the present study is to evaluate the antioxidant and proapoptotic effects of silver–palm pollen (Ag/PP) nanocomposite. The percentage of live cells after treatment with various concentrations of Ag/PP (0, 5, 10, 20, and 40 µM/mL) was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) colorimetric assay. The antioxidant potential of Ag/PP was measured via the scavenging effects of 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and molecular analysis. Apoptosis was assessed by morphological analysis, fluorescent dye, and flow cytometry, and its fundamental mechanism studied based on evaluation of Bax and Bcl2 gene expression. Ag/PP nanocomposite suppressed the viability of MCF-7 cells (dose and time dependently) and showed antioxidant properties. Morphological changes associated with cell death were observed in treated cells. Accumulation of dead cells in sub-G1 phase confirmed the occurrence of apoptosis in exposed cells. In addition, NPs induced cell death by altering Bcl-2 expression in MCF-7 cells. These results indicate that Ag/PP nanocomposite is an effective combination for removal of cancer cells by induction of apoptosis and could be useful for human health due to its antioxidant effects.     

Design,synthesis and evaluation of novel dehydroabietic acid-dithiocarbamate hybrids as potential multi-targeted compounds for tumor cytotoxicity

In the present study, novel representatives of the important group of biologically-active, dehydroabietic acid-bearing dithiocarbamate moiety, were synthesized and characterized by ¹H NMR, ¹³C NMR, HR-MS. The in vitro antiproliferative activity evaluation (MTT) indicated that these compounds exhibited potent inhibitory activities in various cancer cell lines (HepG-2, MCF-7, HeLa, T-24, MGC-803). Particularly, compound III-b possessed extraordinary cytotoxicity with low micromolar IC₅₀ values ranging from 4.07 to 38.84 µM against tested cancer cell lines, while displayed weak cytotoxicity on two normal cell lines (LO-2 and HEK 293 T). Subsequently, the potential mechanisms of representative compound III-b were elementarily investigated by Transwell experiment, which showed III-b can inhibit cancer cells migration. Annexin-V/PI dual staining showed that the compound can induce HepG-2 cells apoptosis in a dose-dependent manner. Meanwhile this apoptosis may be related to the upregulated protein expression of cleaved-caspase 3, cleaved-caspase 9, Bax and downregulated of Bcl-2 indicated by Western Blot. Later study further confirmed that ROS levels in HepG-2 cells increased significantly with the rise of concentrations. In addition, through the network pharmacology data analyzing, the core targets and signaling pathways of compound III-b for treatment of liver neoplasms were forecasted. Molecular docking model showed that compound III-b had high affinity with hub targets (CASP3, EGFR, HSP90AA1, MAPK1, ERBB2, MDM2), suggesting that compound III-b might target the hub protein to modulate signaling activity. Taken together, these data indicated that dehydroabietic acid structural modification following the “Molecular hybridization” principle is a feasible way to discover the potential multi-targeted antitumor compounds.     

Valtrate from Valeriana jatamansi Jones induces apoptosis and inhibits migration of human breast cancer cells in vitro

Abstract

Valtrate is a principle compound isolated from Valeriana jatamansi Jones, a traditional Chinese folk medicine originally used to treat various nervous disorders. Here, we found that valtrate exhibited significant anti-cancer activity in vitro, especially in human breast cancer cells, while displayed relatively low cytotoxicity to normal human breast epithelial cells (MCF 10A). Valtrate induced cell cycle arrest at G2/M stage and apoptosis in MDA-MB-231 and MCF-7 cells, with reduced expression of p-Akt (Ser 473), cyclin B1 and caspase 8, and increased expression of p21, p-cdc2, cleaved-caspase 3, cleaved-caspase 7 and poly (ADP-ribose) polymerase (PARP). In addition, valtrate inhibited cell migration through down-regulation of MMP-9 and MMP-2 expression. These results demonstrate that valtrate possesses anti-breast cancer activities via cell cycle arrest, apoptosis, and inhibition of cell migration, thus supporting valtrate as a potential antitumor agent.     

Structural characterization and biological activity of galactoglucan from Castanea mollissima Blume

Abstract

A galactoglucan (HCPA) was extracted from C. mollissima Blume fruits using hot water, which was composed of glucose and galactose, with a molecular weight of 5.5?kDa. Methylation and 1?D, 2?D NMR spectroscopy analysis showed that HCPA contained [→4)-α-D-Glcp(1→], [→4,6)-α-D-Glcp(1→], [→4)-β-D-Galp(1→] and [α-D-Glcp(1→] motifs in a molar ratio of approximately 6.11:1.08:1.00:1.03. HCPA showed a spherical-like structure as detected by scanning electron microscope (SEM). HCPA biological activity was investigated in vitro. The results showed that HCPA inhibited the proliferation of HeLa, MCF-7 and MGC-803 cells, induced HeLa cells apoptosis and arrested cell cycle in G2/M phase of HeLa cells. HCPA also enhanced the viability and phagocytic ability of RAW 264.7 cells and stimulated the production of NO, TNF-α and IL-6. The results demonstrated that HCPA had a potent antitumor and immunomodulating effects in vitro, suggesting its potential use as functional food and drug products.     

Chitinase inhibits growth of human breast and colorectal cancer cells in vitro and Ehrlich ascites carcinoma cells in vivo

Trichosanthes dioica seed extract was loaded on a QA-cellulose column and the unbound fraction with the chitinase activity was run on SDS-PAGE. Multiple bands were observed and were separated by a Sephadex G-50 column. The combination of the 6 and 33 kDa masses supported the degradation of chitinase as purified earlier. Only the 33 kDa fraction contained sugar and showed chitinase activity. The chitinase was also isolated by using a chitin column. At 200 µg/ml protein concentration, the chitinase inhibited 49.1 %, 48.8 % and 38.12 % of Ehrlich ascites carcinoma, HCT-116 and MCF-7 cells growth, respectively, in a dose-dependent manner. Exactly, 46 % and 82 % EAC cell growth inhibition were observed after treating the EAC cells bearing Swiss albino mice with the chitinase at the doses of 1.0 and 2.0 mg/Kg/day respectively. EAC, HCT-116 and MCF-7 cells growth inhibitions were due to the induction of apoptosis. ROS was accumulated in HCT-116 and MCF-7 cells. After treatment of HCT-116 cells, the expression level of p53 and TNFα genes increased and PARP gene decreased. On the other hand, elevated expression was observed for PARP, MAPK, NFκB, FAS, FADD, and Caspase-8 genes in MCF-7 cells. The induction of apoptosis in HCT-116 was further confirmed by caspase protein expression. The chitinase causes ‘S’ cell cycle arrest in MCF-7 and HCT-116 cells. T. dioica seed chitinase inhibited EAC, HCT-116 and MCF-7 cells by inducing apoptosis in vitro and EAC in vivo in mice. These promising results indicated that T. dioica seed chitinase can be an anticancer agent.     

The death of human cancer cells following photodynamic therapy: apoptosis competence is necessary for Bcl-2 protection but not for induction of autophagy

Photodynamic therapy (PDT) is an efficient inducer of apoptosis in many types of cells, except in cells deficient in one or more of the factors that mediate apoptosis. Recent reports have identified autophagy as a potential alternative cell death process following PDT. Here we investigated the occurrence of autophagy after PDT with the photosensitizer Pc 4 in human cancer cells that are deficient in the pro-apoptotic factor Bax (human prostate cancer DU145 cells) or the apoptosis mediator caspase-3 (human breast cancer MCF-7v cells) and in apoptosis-competent cells (MCF-7c3 cells that stably overexpress human pro-caspase-3 and Chinese hamster ovary CHO 5A100 cells). Further, each of the cell lines was also studied with and without stably overexpressed Bcl-2. Autophagy was identified by electron microscopic observation of the presence of double-membrane-delineated autophagosomal vesicles in the cytosol and by immunoblot observation of the Pc 4-PDT dose- and time-dependent increase in the level of LC3-II, a component of the autophagosomal membrane. Autophagy was observed in all of the cell lines studied, whether or not they were capable of typical apoptosis and whether or not they overexpressed Bcl-2. The presence of stably overexpressed Bcl-2 in the cells protected against PDT-induced apoptosis and loss of clonogenicity in apoptosis-competent cells (MCF-7c3 and CHO 5A100 cells). In contrast, Bcl-2 overexpression did not protect against the development of autophagy in any of the cell lines or against loss of clonogenicity in apoptosis-deficient cells (MCF-7v and DU145 cells). Furthermore, 3-methyladenine and wortmannin, inhibitors of autophagy, provided greater protection against loss of viability to apoptosis-deficient than to apoptosis-competent cells. The results show that autophagy occurs during cell death following PDT in human cancer cells competent or not for normal apoptosis. Only the apoptosis-competent cells are protected by Bcl-2 against cell death.     

Gypensapogenin H from hydrolyzate of total Gynostemma pentaphyllum saponins induces apoptosis in human breast carcinoma cells

Abstract

Gypensapogenin H (Gyp H) is a novel dammarane-type triterpene, isolated from hydrolyzate of total saponins from Gynostemma pentaphyllum. Our previous work demonstrated that Gyp H exhibited potent growth inhibitory effects on tumor cells. It significantly inhibited the growth of human breast cancer cells (MDA-MB-231), while having low toxicity to normal human breast epithelial cells, MCF-10a. Further mechanistic study demonstrated that Gyp H decreased survival, inhibited proliferation, migration, induced apoptosis and led to cell cycle arrest. For the MDA-MB-231 cell lines, Gyp H increased expression of P21, Bax and cytochrome c, induced PARP cleavage and activated caspases. Gyp H also reduced expression of CDK2/4, CyclinD1, E2F1 and Bcl2, which associated with the cell cycle arrest. Thus, our finding may be useful for understanding the mechanism of action of Gyp H on breast cancer cells and suggest that Gyp H would be a leading agent for the treatment of breast cancer.     

Brassinin inhibits proliferation and induces cell cycle arrest and apoptosis in nasopharyngeal cancer C666-1 cells

BackgroundNasopharyngeal cancer is a tumor that occurs in the mucous epithelium of the nasopharynx. Due to its rapid growth and early metastatic nature, the successful treatment of nasopharyngeal cancer is highly challenging.ObjectiveHere, we intended to assess the in vitro anticancer property of brassinin against the nasopharyngeal cancer C666-1 cells.MethodologyThe in vitro free radical scavenging property of the brassinin was assessed by various free radical scavenging activities such as FRAP, DPPH, chemiluminescence (CL), and ORAC assays. The cytotoxic level of the brassinin (1–50 µM) against the nasopharyngeal cancer C666-1 cells and normal Vero cells were assessed by the MTT cytotoxicity assay. The levels of TBARS, GSH, and the SOD activity was assessed using kits. The level of ROS generation, MMP, and apoptosis were investigated by the respective fluorescent staining techniques. The flow cytometry analysis was done to scrutinize the cell cycle arrest. The Bax/Bcl-2 level and caspase activities were examined using respective kits.ResultsThe brassinin treatment effectively scavenged the free radicals, which are assessed by the FRAP, DPPH, chemiluminescence (CL), and ORAC assays. The proliferation of brassinin treated C666-1 cells were decreased remarkably, while the same concentration of brassinin did not disturbed the Vero cell viability. The 30 µM of brassinin effectively increased the ROS production, depleted the MMP, and stimulated the apoptosis in the C666-1 cells. The brassinin increased the TBARS and depleted the GSH and SOD in the C666-1 cells. The flow cytometry analysis revealed that the brassinin administration improved the G0/G1 ratio and decreased the proportion of cells with ‘S’ and ‘G2/M’ phase. The Bax, caspase-3 and ?9 were elevated and Bcl-2 level was decreased in the brassinin administered C666-1 cells.ConclusionOur findings discovered that the brassinin has the capacity to prevent the proliferation and stimulate the apoptotic cell death C666‐1 cells via blocking cell cycle and increasing oxidative stress and apoptotic markers. Hence, it can be a talented therapeutic agent to treat the nasopharyngeal cancer in the future.