Danthron, an anthraquinone derivative, induces DNA damage and caspase cascades-mediated apoptosis in SNU-1 human gastric cancer cells through mitochondrial permeability transition pores and Bax-triggered pathways

9,10-Dioxoanthracenyldithiocarbamates effectively inhibit the proliferation of non-small cell lung cancer by targeting multiple protein tyrosine kinases

Anthraquinones have attracted considerable interest in the realm of cancer treatment owing to their potent anticancer properties. This study evaluates the potential of a series of new anthraquinone derivatives as anticancer agents for non-small-cell lung cancer (NSCLC). The compounds were subjected to a range of tests to assess their cytotoxic and apoptotic properties, ability to inhibit colony formation, pro-DNA damage functions, and capacity to inhibit the activity of tyrosine kinase proteins (PTKs). Based on the research findings, it has been discovered that most active derivatives (i84, i87, and i90) possess a substantial capability to impede the viability of NSCLC while having mostly a negligible effect on the human kidney cell line. Moreover, the anthraquinones displayed pro-apoptotic and genotoxic attributes while blocking the phosphorylation of multiple PTKs. Collectively, our findings indicate that these derivatives may demonstrate promising potential as effective anticancer agents for lung cancer treatment.

Structural Characterization and Anticancer Activity of a New Anthraquinone from Senna velutina (Fabaceae)

In this study, a novel compound was isolated, identified, and its chemical structure was determined from the extract of the roots of Senna velutina. In addition, we sought to evaluate the anticancer potential of this molecule against melanoma and leukemic cell lines and identify the pathways of cell death involved. To this end, a novel anthraquinone was isolated from the barks of the roots of S. velutina, analyzed by HPLC-DAD, and its molecular structure was determined by nuclear magnetic resonance (NMR). Subsequently, their cytotoxic activity was evaluated by the (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) method against non-cancerous, melanoma, and leukemic cells. The migration of melanoma cells was evaluated by the scratch assay. The apoptosis process, caspase-3 activation, analysis of mitochondrial membrane potential, and measurement of ROS were evaluated by flow cytometry technique. In addition, the pharmacological cell death inhibitors NEC-1, RIP-1, BAPTA, Z-VAD, and Z-DEVD were used to confirm the related cell death mechanisms. With the results, it was possible to elucidate the novel compound characterized as 2'-OH-Torosaol I. In normal cells, the compound showed no cytotoxicity in PBMC but reduced the cell viability of all melanoma and leukemic cell lines evaluated. 2'-OH-Torosaol I inhibited chemotaxis of B16F10-Nex2, SK-Mel-19, SK-Mel-28 and SK-Mel-103. The cytotoxicity of the compound was induced by apoptosis via the intrinsic pathway with reduced mitochondrial membrane potential, increased levels of reactive oxygen species, and activation of caspase-3. In addition, the inhibitors demonstrated the involvement of necroptosis and Ca²⁺ in the death process and confirmed caspase-dependent apoptosis death as one of the main programmed cell death pathways induced by 2'-OH-Torosaol I. Taken together, the data characterize the novel anthraquinone 2'-OH-Torosaol I, demonstrating its anticancer activity and potential application in cancer therapy.

Adjuvant therapy with Huatan Sanjie Granules improves the prognosis of patients with primary liver cancer: a cohort study and the investigation of its mechanism of action based on network pharmacology

Objective: Nowadays, primary liver carcinoma (PLC) is one of the major contributors to the global cancer burden, and China has the highest morbidity and mortality rates in the world. As a well-known Chinese herbal medicine (CHM) prescription, Huatan Sanjie Granules (HSG) has been used clinically for many years to treat PLC with remarkable efficacy, but the underlying mechanism of action remains unclear. Methods: A clinical cohort study was conducted to observe the overall survival of PLC patients with vs. without oral administration of HSG. Meanwhile, the BATMAN-TCM database was used to retrieve the potential active ingredients in the six herbs of HSG and their corresponding drug targets. PLC-related targets were then screened through the Gene Expression Omnibus (GEO) database. The protein-protein interaction (PPI) network of targets of HSG against PLC was constructed using Cytoscape software. The cell function assays were further carried out for verification. Results: The results of the cohort study showed that the median survival time of PLC patients exposed to HSG was 269 days, which was 23 days longer than that of the control group (HR, 0.62; 95% CI, 0.38-0.99; p = 0.047). In particular, the median survival time of Barcelona Clinic Liver Cancer stage C patients was 411 days in the exposure group, which was 137 days longer than that in the control group (HR, 0.59; 95% CI, 0.35-0.96; p = 0.036). Meanwhile, the enrichment analysis result for the obtained PPI network consisting of 362 potential core therapeutic targets suggest that HSG may inhibit the growth of liver cancer (LC) cells by blocking the PI3K-Akt/MAPK signaling pathways. Furthermore, the above prediction results were verified by a series of in vitro assays. Specifically, we found that the expressions TP53 and YWHA2, the targets of the hepatitis B virus signaling pathway, were significantly affected by HSG. Conclusion: HSG shows promising therapeutic efficacy in the adjuvant treatment of PLC.

Danthron, an Anthraquinone Isolated from a Marine Fungus, Is a New Inhibitor of Angiogenesis Exhibiting Interesting Antitumor and Antioxidant Properties

The role played by a sustained angiogenesis in cancer and other diseases stimulates the interest in the search for new antiangiogenic drugs. In this manuscript, we provide evidence that 1,8- dihydroxy-9,10-anthraquinone (danthron), isolated from the fermentation broth of the marine fungus Chromolaenicola sp. (HL-114-33-R04), is a new inhibitor of angiogenesis. The results obtained with the in vivo CAM assay indicate that danthron is a potent antiangiogenic compound. In vitro studies with human umbilical endothelial cells (HUVEC) reveal that this anthraquinone inhibits certain key functions of activated endothelial cells, including proliferation, proteolytic and invasive capabilities and tube formation. In vitro studies with human breast carcinoma MDA-MB231 and fibrosarcoma HT1080 cell lines suggest a moderate antitumor and antimetastatic activity of this compound. Antioxidant properties of danthron are evidenced by the observation that it reduces the intracellular reactive oxygen species production and increases the amount of intracellular sulfhydryl groups in endothelial and tumor cells. These results support a putative role of danthron as a new antiangiogenic drug with potential application in the treatment and angioprevention of cancer and other angiogenesis-dependent diseases.

Microbial Biosynthesis of Chrysazin Derivatives in Recombinant Escherichia coli and Their Biological Activities

Anthraquinone and its derivatives show remarkable biological properties such as anticancer, antibacterial, antifungal, and antiviral activities. Hence, anthraquinones derivatives have been of prime interest in drug development. This study developed a recombinant Escherichia coli strain to modify chrysazin to chrysazin-8-O-α-l-rhamnoside (CR) and chrysazin-8-O-α-l-2′-O-methylrhamnoside (CRM) using rhamnosyl transferase and sugar-O-methyltransferase. Biosynthesized CR and CRM were structurally characterized using HPLC, high-resolution mass spectrometry, and various nuclear magnetic resonance analyses. Antimicrobial effects of chrysazin, CR, and CRM against 18 superbugs, including 14 Gram-positive and 4 Gram-negative pathogens, were investigated. CR and CRM exhibited antimicrobial activities against nine pathogens, including methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-sensitive Staphylococcus aureus (MSSA) in a disk diffusion assay at a concentration of 40 µg per disk. There were MIC and MBC values of 7.81−31.25 µg/mL for CR and CRM against methicillin-sensitive S. aureus CCARM 0205 (MSSA) for which the parent chrysazin is more than >1000 µg/mL. Furthermore, the anti-proliferative properties of chrysazin, CR, and CRM were assayed using AGS, Huh7, HL60, and HaCaT cell lines. CR and CRM showed higher antibacterial and anticancer properties than chrysazin.

β-Caryophyllene promotes oxidative stress and apoptosis in KB cells through activation of mitochondrial-mediated pathway - An in-vitro and in-silico study

Beta-caryophyllene (BCP), are natural bicyclic sesquiterpenes which are present in numerous plants worldwide. BCP has antioxidant, antimicrobial, and antifungal properties. Here, we studied its anticancer, anti-inflammatory, and cytotoxic effects. Cells treated with BCP, in a dose-dependent manner, exhibited morphological changes, showed lower cell growth, underwent apoptosis and lost the ability to metastasis through the suppression of NF-ҡ B via PI3K/AKT signalling pathway. These results elucidate that the inhibition of NF-ҡ B and PI3K/AKT is one of the most important mechanism by which BCP suppresses cancer cell proliferation and enhances apoptosis.

Nanomaterials in Smart Packaging Applications: A Review

Food wastage is a critical and world-wide issue resulting from an excess of food supply, poor food storage, poor marketing, and unstable markets. Since food quality depends on consumer standards, it becomes necessary to monitor the quality to ensure it meets those standards. Embedding sensors with active nanomaterials in food packaging enables customers to monitor the quality of their food in real-time. Though there are many different sensors that can monitor food quality and safety, pH sensors and time-temperature indicators (TTIs) are the most critical metrics in indicating quality. This review showcases some of the recent progress, their importance, preconditions, and the various future needs of pH sensors and TTIs in food packaging for smart sensors in food packaging applications. In discussing these topics, this review includes the materials used to make these sensors, which vary from polymers, metals, metal-oxides, carbon-based materials; and their modes of fabrication, ranging from thin or thick film deposition methods, solution-based chemistry, and electrodeposition. By discussing the use of these materials, novel fabrication process, and problems for the two sensors, this review offers solutions to a brighter future for the use of nanomaterials for pH indicator and TTIs in food packaging applications.

Nutraceuticals: Transformation of Conventional Foods into Health Promoters/Disease Preventers and Safety Considerations

Nutraceuticals are essential food constituents that provide nutritional benefits as well as medicinal effects. The benefits of these foods are due to the presence of active compounds such as carotenoids, collagen hydrolysate, and dietary fibers. Nutraceuticals have been found to positively affect cardiovascular and immune system health and have a role in infection and cancer prevention. Nutraceuticals can be categorized into different classes based on their nature and mode of action. In this review, different classifications of nutraceuticals and their potential therapeutic activity, such as anti-cancer, antioxidant, anti-inflammatory and anti-lipid activity in disease will be reviewed. Moreover, the different mechanisms of action of these products, applications, and safety upon consumers including current trends and future prospect of nutraceuticals will be included.

Induction of Apoptosis, Inhibition of MCL-1, and VEGF-A Expression Are Associated with the Anti-Cancer Efficacy of Magnolol Combined with Regorafenib in Hepatocellular Carcinoma

While regorafenib was approved for the treatment of advanced HCC in 2017, with a partial response and survival benefit; other combination agents to facilitate the efficacy of regorafenib still need to be explored. Magnolol is a potential natural anti-tumor compound for many types of cancers. Combination indexes calculated on the basis of both in vitro and in vivo models have indicated a synergistic effect of the combination of regorafenib and magnolol. The overexpression of the VEGF-A protein significantly diminished regorafenib's inhibition of cell viability, while the transient knockdown of VEGF-A by siRNA effectively sensitized HCC cells to regorafenib. In addition, the inhibition of MCL-1 by siRNA combined with regorafenib allowed for a significantly greater inhibition of cell growth, compared to regorafenib alone. A lower protein expression level for VEGF-A and MCL-1 was found for the combination treatment of HCC in vitro and in vivo. A superior metastasis inhibition was also found in the combination group, as compared to the single-treatment groups, using a transwell assay, wound healing assay, and Western blotting. The caspase-dependent and -independent and DNA damage effects, as determined by flow cytometry and a comet assay, were increased by the combination therapy. Taken together, magnolol sensitized HCC to regorafenib, which was correlated with the reduction of VEGF-A and MCL-1 and the induction of apoptosis.

Physcion and Physcion 8-O-β-D-glucopyranoside: Natural Anthraquinones with Potential Anticancer Activities

Nature has provided prodigious reservoirs of pharmacologically active compounds for drug development since times. Physcion and physcion 8-O-β-D-glucopyranoside (PG) are bioactive natural anthraquinones which exert anti-inflammatory and anticancer properties with minimum or no adverse effects. Moreover, physcion also exhibits anti-microbial and hepatoprotective properties, while PG is known to have anti-sepsis as well as ameliorative activities against dementia. This review aims to highlight the natural sources and anticancer activities of physcion and PG, along with associated mechanisms of actions. On the basis of the literature, physcion and PG regulate multitudinous cell signaling pathways through the modulation of various regulators of cell cycle, protein kinases, microRNAs, transcriptional factors, and apoptosis linked proteins resulting in the effective killing of cancerous cells in vitro as well as in vivo. Both compounds effectively suppress metastasis, furthermore, physcion acts as an inhibitor of 6PGD and also plays an important role in chemosensitization. This review article suggests that physcion and PG are potent anticancer drug candidates, but further investigations on their mechanism of action and pre-clinical trials are mandatory in order to comprehend the full potential of these natural cancer killers in anticancer remedies.

Cytotoxicity and apoptosis induction by Fumaria officinalis extracts in leukemia and multiple myeloma cell lines

ETHNOPHARMACOLOGICAL RELEVANCE

Fumaria officinalis (Fumariaceae) is recorded in the Kurdish ethnobotany for various health problems.

AIM OF THE STUDY

In this study, the cytotoxic activity of F. officinalis extracts on two leukemia and nine multiple myeloma (MM) cell lines was investigated.

MATERIALS AND METHODS

The cytotoxic and ferroptotic activity were examined by resazurin reduction assay. Flow cytometry, immunoblotting assay and fluorescence microscopy were used to measure cell cycle distribution, apoptosis, induction of reactive oxygen species (ROS), loss integrity of mitochondrial membrane potential (MMP) and autophagy. LC-ESI/MS was used to identify chemical constituents present in F. officinalis.

RESULTS

Chloroform (CF) and ethyl acetate (EF) fractions showed drastic cytotoxic effect on CCRF-CEM and CEM/ADR 5000 cells. NCI-H929 cell line exhibited higher sensitivity against CF, while EF demonstrated its higher cytotoxicity on OPM-2 cells with IC₅₀ value 14.80 ± 1.70 and 28.13 ± 1.38 μg/mL respectively. Flow cytometric and morphological studies confirmed that CF and EF induced apoptosis in NCI-H929 cells by loss of MMP, generation of ROS and obvious morphological variations. In DNA histograms, up to 50% of the cells were accumulated by CF and 44% by EF in the sub-G0/G1 phase following 72 h treatment. EF induced autophagic cell death, while CF stimulated iron-dependent cell death. Moreover, two isoquinoline alkaloids and four flavonoids were identified in the active fractions.

CONCLUSION

To our knowledge, this is the first report demonstrating the cytotoxicity of F. officinalis extracts in MM cell lines. CF and EF fractions inhibited MM cell proliferation through various modes of actions.

Methylphenidate causes cytotoxicity on photoreceptor cells via autophagy

Methylphenidate (MPH) is used as the first-line treatment for attention-deficit hyperactivity disorder. However, there are concerns that this treatment may be associated with increased risk of retinal damage. This study was to investigate cytotoxicity of MPH on photoreceptor cells and explore its underlying mechanisms. MPH-caused cell toxicity was established in 661 W cells. Cytotoxicity was evaluated by 3-(4,5-dimethylthiazol)-2,5-diphenyltetrazolium-bromid and lactate dehydrogenase assays. Oxidative stress was measured by the markers: glutathione (GSH) reductase, catalase, and superoxide dismutase activities as well as GSH, reactive oxygen species, and malondialdehyde levels. Gene and protein expression was detected by real-time polymerase chain reaction (PCR) and western blot, respectively. Results showed that MPH decreased 661 W cell viability, increased caspase-3/9 activities, and induced oxidative stress. Furthermore, MPH treatment increased messenger RNA (mRNA) expression of Beclin-1 and microtubule-associated protein 1A/1B-light chain 3B (LC3B) protein expression in 661 W cells, suggesting autophagy was induced. MPH treatment also upregulated p-JAK1/p-STAT1 protein expression. These data demonstrated that MPH could increase oxidative stress in photoreceptor cells to cause cell toxicity via autophagy, providing the scientific rationale for the photoreceptor cell damage caused by the MPH administration.

Sensitivity of allyl isothiocyanate to induce apoptosis via ER stress and the mitochondrial pathway upon ROS production in colorectal adenocarcinoma cells

Allyl isothiocyanate (AITC), a bioactive phytochemical compound that is a constituent of dietary cruciferous vegetables, possesses promising chemopreventive and anticancer effects. However, reports of AITC exerting antitumor effects on apoptosis induction of colorectal cancer (CRC) cells in vitro are not well elucidated. The present study focused on the functional mechanism of the endoplasmic reticulum (ER) stress-based apoptotic machinery induced by AITC in human colorectal cancer HT-29 cells. Our results indicated that AITC decreased cell growth and number, reduced viability, and facilitated morphological changes of apoptotic cell death. DNA analysis by flow cytometry showed G2/M phase arrest, and alterations in the modulated protein levels caused by AITC were detected via western blot analysis. AITC also triggered vital intrinsic apoptotic factors (caspase-9/caspase-3 activity), disrupted mitochondrial membrane potential, and stimulated mitochondrial-related apoptotic molecules (e.g., cytochrome c, apoptotic protease activating factor 1, apoptosis-inducing factor, and endonuclease G). Additionally, AITC prompted induced cytosolic Ca²⁺ release and Ca²⁺-dependent ER stress-related signals, such as calpain 1, activating transcription factor 6α, glucose-regulated proteins 78 and 94, growth arrest- and DNA damage-inducible protein 153 (GADD153), and caspase-4. The level of reactive oxygen species (ROS) production was found to induce the hallmark of ER stress GADD153, proapoptotic marker caspase-3, and calpain activity after AITC treatment. Our findings showed for the first time that AITC induced G2/M phase arrest and apoptotic death via ROS-based ER stress and the intrinsic pathway (mitochondrial-dependent) in HT-29 cells. Overall, AITC may exert an epigenetic effect and is a potential bioactive compound for CRC treatment.

Potential effects of allyl isothiocyanate on inhibiting cellular proliferation and inducing apoptotic pathway in human cisplatin-resistant oral cancer cells

BACKGROUND/PURPOSE

Cisplatin-resistant oral cancer is clinically difficult to manage and the dose-dependent toxicities of cisplatin has been widely concerned. Allyl isothiocyanate (AITC), known as mustard oil, is a plant-derived compound abundant in cruciferous vegetables. It is reported to have anti-cancer potential as a natural dietary chemopreventive compound against a variety of cancers, but the effect of AITC on cisplatin-resistant cancer cells is still little-known.

METHODS

Human CAL27-cisplatin-resistant oral cancer cells (CAR cells) were examined to investigate the antitumor properties of AITC. 3-(4,5-dimethylthiazol-2-yl)-2,5- diphenyltetrazolium bromide (MTT) assay, IncuCyte™ S3 cell proliferation assay, 4',6-diamidino-2-phenylindole (DAPI) and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining as well as Western blot analysis were deployed.

RESULTS

AITC decreased CAR cell viability, induced cell death of CAR cells and inhibited the confluences of cultured CAR cells. When CAR cells were treated with AITC, activation of caspase-3 and caspase-9 by AITC was observed and could be reversed by Z-VAD-fmk (pan-caspase inhibitor). Furthermore, the protein expressions of phosphorylated protein kinase B (p-AKT) and phosphorylated mammalian target of rapamycin (p-mTOR) were suppressed in AITC-treated CAR cells, whereas protein expressions of Bax, cytochrome c, Apaf-1, cleaved caspase-3, and cleaved caspase-9 were upregulated in AITC-treated CAR cells.

CONCLUSION

AITC can inhibit Akt/mTOR proliferation signaling and promote mitochondria-dependent apoptotic pathway through AITC-enhanced activities of caspase-3 and caspase-9 in CAR cells.

JAK1/STAT3 regulatory effect of β-caryophyllene on MG-63 osteosarcoma cells via ROS-induced apoptotic mitochondrial pathway by DNA fragmentation

Currently, available treatment for osteosarcoma is combinational chemotherapy of doxorubicin, cisplatin, and methotrexate before and after surgery with overall 5-year survival rate of less than 40%. The present study was aimed to assess the anticancer effects of a phytochemical named β-caryophyllene (BCP) in treating osteosarcoma. We assessed the effect of (BCP) on oxidative stress, proliferation, apoptosis, and inflammation in human bone cancer cells MG-63. Our results showed that BCP induced reactive oxygen species (ROS) generation at 20 µM concentration in MG-63 cells. The same dose was also shown to exhibit proapoptotic and antiproliferative effects in bone cancer cells MG-63. We demonstrated that the treatment of MG-63 cells with BCP prompted mitochondrial apoptosis via upregulation of Bax and caspase-3 and downregulation of Bcl-2 as well as prompted mitochondrial membrane potential. Our results also showed stimulation of Janus kinase 1/signal transducer and activator of transcription 3 (JAK1/STAT3) signaling pathway in bone cancer MG-63 cells upon BCP treatment along with the induction of proinflammatory genes at the messenger RNA level. Overall results suggest that the treatment of MG-63 cells with BCP promotes apoptosis and inflammation via ROS and JAK1/STAT3 signaling pathway.

Anthraquinone: a promising scaffold for the discovery and development of therapeutic agents in cancer therapy

Cancer, characterized by uncontrolled malignant neoplasm, is a leading cause of death in both advanced and emerging countries. Although, ample drugs are accessible in the market to intervene with tumor progression, none are totally effective and safe. Natural anthraquinone (AQ) equivalents such as emodin, aloe-emodin, alchemix and many synthetic analogs extend their antitumor activity on different targets including telomerase, topoisomerases, kinases, matrix metalloproteinases, DNA and different phases of cell lines. Nano drug delivery strategies are advanced tools which deliver drugs into tumor cells with minimum drug leakage to normal cells. This review delineates the way AQ derivatives are binding on these targets by abolishing tumor cells to produce anticancer activity and purview of nanoformulations related to AQ analogs.

Biosynthesis of Rhamnosylated Anthraquinones in Escherichia coli

Rhamnose is a naturally occurring deoxysugar present as a glycogenic component of plant and microbial natural products. A recombinant mutant Escherichia coli strain was developed by overexpressing genes involved in the TDP-L-rhamnose biosynthesis pathway of different bacterial strains and Saccharothrix espanaensis rhamnosyl transferase to conjugate intrinsic cytosolic TDP-L-rhamnose with anthraquinones supplemented exogenously. Among the five anthraquinones (alizarin, emodin, chrysazin, anthrarufin, and quinizarin) tested, quinizarin was biotransformed into a rhamoside derivative with the highest conversion ratio by whole cells of engineered E. coli. The quinizarin glycoside was identified by various chromatographic and spectroscopic analyses. The anti-proliferative property of the newly synthesized rhamnoside, quinizarin-4-O-α-L-rhamnoside, was assayed in various cancer cells.

Discovery and characterization of four glycosyltransferases involved in anthraquinone glycoside biosynthesis in Rubia yunnanensis

Four new glycosyltransferases, which were discovered from Rubia yunnanensis for mediating anthraquinone glycoside biosynthesis, were identified through the analysis of broad substrates, sugar promiscuous, and regioselective glycosylation.

Eriodictyol exerts potent anticancer activity against A549 human lung cancer cell line by inducing mitochondrial-mediated apoptosis, G2/M cell cycle arrest and inhibition of m-TOR/PI3K/Akt signalling pathway

INTRODUCTION

Eriodictyol is an important flavonoid and is commonly present across the plant kingdom. Flavonoids have been reported to show incredible pharmacological potential. However, the anticancer activity of the important flavonoid eriodictyol has not been well reported. In the present study we determined its anticancer potential against the human lung cancer cell line A549.

MATERIAL AND METHODS

The initial cytotoxicity induced by eriodictyol was measured by MTT assay. Flow cytometry was used to study the effects of eriodictyol on apoptosis, cell cycle phase distribution and mitochondrial membrane potential loss. The comet assay was used to measure DNA damage induced by eriodictyol in cancer cells while the western blot assay indicated effects of the compound on Bax/Blc-2 and PI3K/AKT/m-TOR proteins.

RESULTS

The results showed that eriodictyol has an IC₅₀ value of 50 μM against human lung cancer cells as compared to the IC₅₀ of 95 µM against non-cancerous FR2 cells. The molecule exerted its anticancer activity through induction of apoptosis by regulating the Bcl-2/Bax signalling pathway. It caused cell cycle arrest of human lung cancer A549 cells at G2/M phase. Eriodictyol was also found to cause a reduction of the mitochondrial membrane potential in a dose-dependent manner. Additionally, eriodictyol effectively inhibited the mTOR/PI3K/Akt signalling pathway in a dose-dependent manner.

CONCLUSIONS

Based on the above findings, we conclude that eriodictyol exerts its anticancer activity through induction of mitochondrial apoptosis and G2/M cell cycle arrest and inhibition of the TOR/PI3K/Akt cascade, indicating that it may have potential as a lead compound in the treatment of lung cancer, provided further in depth studies are done.

Anti-gastric cancer effect of Salidroside through elevating miR-99a expression

Salidroside is an active ingredient extracted from Rhodiola rosea that has anti-tumor activities. The current paper attempted to assess the impact of Salidroside on gastric cancer (GC) and explore the potential mechanism. GC cell lines (SNU-216 and MGC803) and gastric epithelial cell line GES-1 were treated with Salidroside. CCK-8 assay, colony formation assay, flow cytometry and Transwell assay were respectively performed to evaluate GC cells phenotype. qRT-PCR and western blot were conducted to reveal the downstream genes and signaling of Salidroside. We found that 800 μM Salidroside was capable of reducing GC cells viability, while has no such impacts on GES-1 cells. Salidroside inhibited GC cells proliferation, migration, invasion and promoted apoptosis, which coupled with the down-regulation of p21, Bcl-2, MMP2, RhoA, p-ROCK1, Vimentin and the up-regulations of CyclinD1, Bax, cleaved caspases. miR-99a was found to be highly expressed in response to Salidroside treatment. Besides, the inhibition of MAPK/ERK and PI3K/AKT signaling induced by Salidroside was attenuated by miR-99a silence and in this process, IGF1R worked as a target of miR-99a. The anti-GC effect of Salidroside was also confirmed in a mouse model of GC. The promoting effect of Salidroside on miR-99a expression was also verified in vivo. Furthermore, Salidroside promoted the cisplatin-sensitivity of SGC7901/DDP cells. In conclusion, this study demonstrated that Salidroside possessed anti-GC effects through regulating miR-99a/IGF1R axis and inhibiting MAPK/ERK and PI3K/AKT pathways.

Chemomodulatory effects of Alysicarpus vaginalis extract via mitochondria-dependent apoptosis and necroptosis in breast cancer

The present study intended to assess the anticancer potential of Alysicarpus vaginalis ethyl acetate fraction (AVEAF) in breast cancer cell lines (MCF-7 and MDA-MB-453) and against N-methyl-N-nitrosourea (MNU) induced mammary carcinoma in Sprague-Dawley rats which resemble the human estrogen dependent breast cancer. The SRB assay showed that the maximum growth inhibition rate of AVEAF on MCF-7 cell was 27.12 at 100 µg/ml. Flow cytometry analysis observed that AVEAF induced the cell cycle arrest at the S phases and decreased in mitochondrial membrane potential on the MCF-7 cells. AVEAF elevated intracellular ROS level in the MCF-7 cells which were reversed with N-acetycysteine (2 mM) pretreatment indicating that AVEAF induced mitochondrial-mediated apoptosis via augmentation of intracellular ROS. Western blotting exhibited that AVEAF increased the expression of pro-apoptotic protein Bax while decreasing anti-apoptotic proteins Bcl-2 and Bcl-xL expression which promoted the cleavage of caspase-9, PARP1, RIPK 1, and RIPK 3. Additionally, AVEAF exerted anticancer effect on tumor-bearing rats and the tumor inhibition rate is 50%. Data of the study indicate that AVEAF exhibits In Vitro and In Vivo anticancer activities that associate with its ROS-mediated mitochondrial-mediated intrinsic pathway of apoptosis and necroptosis in MCF-7 cells and may serve as a potential against breast cancer.

Genistein-triggered anticancer activity against liver cancer cell line HepG2 involves ROS generation, mitochondrial apoptosis, G2/M cell cycle arrest and inhibition of cell migration

INTRODUCTION

Liver cancer is one of the most common malignancies across the globe and one of the major causes of cancer-related mortality. With limited available treatment options, there is an urgent need to look for new available options. Genistein is an important plant flavonoid and has been shown to possess tremendous pharmacological potential. The objective of the present study was therefore to evaluate the anticancer effect of the genistein.

MATERIAL AND METHODS

The antiproliferative activity and IC₅₀ of genistein were determined by MTT assay. Reactive oxygen species (ROS) and cycle distribution were investigated by flow cytometry. Apoptosis was detected by DAPI and annexin V/IP staining. Cell migration was investigated by wound healing assay. Protein expression was estimated by western blotting.

RESULTS

MTT assay revealed that genistein reduced the cell viability of HepG2 cancer cells in a dose-dependent manner. Genistein also reduced the colony forming potential of the HepG2 cell concentration dependently. The IC₅₀ of genistein was found to be 25 μM. Genistein caused G2/M cell cycle arrest and G2/M cells increased from 4.2% in the control to 56.4% at 100 μM concentration. Genistein prompted generation of significant (p < 0.01) amounts of ROS, ultimately favouring cell death. Genistein also triggered apoptosis which was associated with upregulation of cytosolic cytochrome c, Bax, cleaved caspase 3 and 9 expression and downregulation of Bcl-2 expression in HepG2 cells.

CONCLUSIONS

We propose that genistein exhibits significant anticancer activity against liver cancer and therefore may prove beneficial in the management of liver cancer.

Biological activity and stability analyses of knipholone anthrone, a phenyl anthraquinone derivative isolated from Kniphofia foliosa Hochst

Knipholone (1) and knipholone anthrone (2), isolated from the Ethiopian medicinal plant Kniphofia foliosa Hochst. are two phenyl anthraquinone derivatives, a compound class known for biological activity. In the present study, we describe the activity of both 1 and 2 in several biological assays including cytotoxicity against four human cell lines (Jurkat, HEK293, SH-SY5Y and HT-29), antiplasmodial activity against Plasmodium falciparum 3D7 strain, anthelmintic activity against the model organism Caenorhabditis elegans, antibacterial activity against Aliivibrio fischeri and Mycobacterium tuberculosis and anti-HIV-1 activity in peripheral blood mononuclear cells (PBMCs) infected with HIV-1_c. In parallel, we investigated the stability of knipholone (2) in solution and in culture media. Compound 1 displays strong cytotoxicity against Jurkat, HEK293 and SH-SY5Y cells with growth inhibition ranging from approximately 62-95% when added to cells at 50 μM, whereas KA (2) exhibits weak to strong activity with 26, 48 and 70% inhibition of cell growth, respectively. Both 1 and 2 possess significant antiplasmodial activity against Plasmodium falciparum 3D7 strain with IC₅₀ values of 1.9 and 0.7 μM, respectively. These results complement previously reported data on the cytotoxicity and antiplasmodial activity of 1 and 2. Furthermore, compound 2 showed HIV-1_c replication inhibition (growth inhibition higher than 60% at tested concentrations 0.5, 5, 15 and 50 μg/ml and an EC₅₀ value of 4.3 μM) associated with cytotoxicity against uninfected PBMCs. The stability study based on preincubation, HPLC and APCI-MS (atmospheric-pressure chemical ionization mass spectrometry) analysis indicates that compound 2 is unstable in culture media and readily oxidizes to form compound 1. Therefore, the biological activity attributed to 2 might be influenced by its degradation products in media including 1 and other possible dimers. Hence, bioactivity results previously reported from this compound should be taken with caution and checked if they differ from those of its degradation products. To the best of our knowledge, this is the first report on the anti-HIV activity and stability analysis of compound 2.

Health functions and structure-activity relationships of natural anthraquinones from plants

Anthraquinone compounds with the anthraquinone ring structure are widely found in traditional Chinese medicines and they are attracting a lot of attention due to their good pharmacological activity. Diversities of anthraquinones depend on their chemical structures, such as the number of anthraquinone rings and the substituents; what's more, the difference in chemical structure determines the difference in physiological activity. Based on results of previous studies, this review summarizes several natural anthraquinones identified from Chinese herbal medicines and their physiological activities including anti-cancer, anti-pathogenic microorganisms, anti-inflammatory, anti-oxidation, anti-osteoporosis, anti-depression, and anti-constipation. The source, effect, model, and action mechanism of the active anthraquinones are described in detail, from which their structure-activity relationship is summarized. By analyzing the relationship between anthraquinone structure and function, we found that, on the whole structure, the anthraquinone ring and anthraquinone glycosides have significant anticancer activity and anti-constipation activity, while for their substituents, anthraquinones substituted by alizarin have significant antioxidant activity and the polarity of the substituents is closely related to their antibacterial activities.

Synthesis and biological evaluation of amino acid derivatives containing chrysin that induce apoptosis

A series of chrysin amino acid derivatives were synthesized to evaluate for their antiproliferative activities against several cancer cell lines. Among the compounds tested, N-(2-((5-hydroxy-4-oxo-2-phenyl-4H-chromen-7-yl)oxy)octanoyl)-L-leucine methyl ester(5d) presented a good anti-proliferative activity in MDA-MB-231 and MCF-7 cells. Flow cytometry analysis showed that 5d induced apoptosis and prolonged cell cycle progression in MDA-MB-231 and MCF-7 cells. Western blot analysis showed that 5d significantly inhibited Akt phosphorylation (Ser473) in MDA-MB-231 and MCF-7 cells. In addition, 5d treatment markedly downregulated Bcl-2 and upregulated Bax in a dose-dependent manner. In vitro caspase activation assay showed that 5d induced apoptosis of MDA-MB-231 cells by enhancing caspase 3/7 activity. The regulatory effect of 5d on apoptosis of MDA-MB-231 and MCF-7 cells may be induced by mitochondrial apoptosis pathway. This study is of great significance for designing and developing more effective chrysin amino acid derivatives.

Leukemia growth is inhibited by benzoxime without causing any harmful effect in rats bearing RBL-1 ×enotransplants

The present study aimed to investigate the effect of benzoxime on leukemia RBL-1 cell proliferation and a leukemic Sprague-Dawley rat model. Proliferation of RBL-1 cells was determined using an MTT assay. Sprague-Dawley rats were assigned randomly into three groups of 10 animals each, where the positive control group was administered an intravenous injection of normal saline, the negative control group was administered 1×10⁶ RBL-1 cells and the treatment group was administered with 1×10⁶ RBL-1 cells and then benzoxime (50 mg/kg/day) for 1 week. Increased dosage of benzoxime reduced RBL-1 cell viability from 92 at 2 µM to ٢١٪ at ١٢ µM after ٢٤ h. Benzoxime treatment prevented the loss of body weight in the rats with leukemia. Compared with the negative control rats, the body weight was determined to be significantly reduced (P<0.05) in the positive control rats. The weight of the spleen and liver was determined to be significantly increased (P<0.02) in the positive control rats and the benzoxime-treated rats compared with that in the negative control group on day 35 of RBL-1 cell implantation. Analysis of leukocytes in rats on day 35 demonstrated a significant reduction (P<0.05) in the cluster of differentiation (CD)11b and CD45 level in the positive control group compared with that in the negative control group. The level of CD11b and CD45 was determined to be similar in the rats in the benzoxime treatment and negative control groups. Analysis of the level of serum glutamic pyruvic transaminase, serum glutamic oxaloacetic transaminase and blood urea nitrogen indicated that all three components exhibited no significant changes in the rats following treatment with benzoxime compared with the component levels in the negative control group. The levels of these three components were in the normal range in rats treated with benzoxime on day 35 of cell implantation. These data demonstrated that the liver and kidneys are not influenced by benzoxime in rats with leukemia. In summary, the present study demonstrated that benzoxime efficiently prevents leukemia growth without inducing any harmful effects in rat models through targeting CD11b and CD45 level; thus, benzoxime should be evaluated further regarding its use in the treatment of leukemia.

Novel triazole analogs of apigenin-7-methyl ether exhibit potent antitumor activity against ovarian carcinoma cells via the induction of mitochondrial-mediated apoptosis

Ovarian cancer is one of the main causes of cancer-associated mortality across the world. Currently, ovarian cancer is mainly treated with chemotherapy. However, ovarian cancer is detected at advanced stages and chemotherapy has numerous side effects. In addition, the results of current chemotherapy on the treatment of ovarian cancer are less than satisfactory. Therefore, there is an urgent need to develop novel and more viable chemotherapeutic agents that can be used to treat ovarian cancer. The present study was designed to synthesize a series of novel triazole analogs of the bioactive apigenin-7-methyl ether to evaluate its anticancer activity against three human ovarian cancer cell lines. A total of eight novel triazole derivatives were synthesized and screened for their anticancer activity. Of all the derivatives, a derivative named 3d exhibited significant and dose-dependent anticancer activity against the SKOV3 ovarian cancer cell line. The IC₅₀ of 3d was found to be 10 µM against the SKOV3 cancer cell line. It was also observed that 3d induced apoptosis in SKOV3 cancer cells through the accretion of reactive oxygen species and reduction in mitochondrial membrane potential. The molecule also modulated the expression of B-cell lymphoma 2 (Bcl-2) and Bcl-2-associated X protein. Taken together, these results showed that the apigenein-7-methyl ether novel derivative 3d may prove an important lead molecule for the treatment of ovarian cancer.

Antitumor Ability of KT2 Peptide Derived from Leukocyte Peptide of Crocodile Against Human HCT116 Colon Cancer Xenografts

BACKGROUND/AIM

Many antimicrobial peptides have been shown to have anticancer activity against human cancer cell lines. Cationic KT2 peptide, derived from white blood cell extract of Crocodylus siamensis has antibacterial activity and antitumor activity against human cervical cancer cells, but there are no data on the effect of KT2 peptide on tumor growth in vivo. The anticancer activity of KT2 peptide on human colon cancer xenografts was investigated in nude mice.

MATERIALS AND METHODS

Tumors in nude mice (BALB/c -nu/nu mice) were induced by subcutaneous injection with HCT116 cells. Twelve days after cancer cell xenograft, mice were treated by intratumoral injection with phosphate-buffered saline or KT2 peptide (25 and 50 mg/kg) once every 2 days for a total of four times and mice were sacrificed at 2 days after the last treatment.

RESULTS

KT2 peptide treatment did not lead to significant difference in mouse body weight among groups, but reduced both tumor volume and weight of colon cancer xenografts. Moreover, KT2 peptide increased the expression of apoptotic proteins, such as BCL2-associated X (BAX), cleaved caspase-3, and poly (ADP-ribose) polymerase and reduced that of BCL2 apoptosis regulator in xenograft tumors.

CONCLUSION

This finding suggests that KT2 peptide may inhibit tumor growth via apoptosis induction in this mouse model and supports the antitumor ability of KT2 peptide.

Danthron suppresses autophagy and sensitizes pancreatic cancer cells to doxorubicin

In contrast to the steady increase in survival observed for most cancer types, advances have been slow for pancreatic cancers. Current chemotherapy has limited benefits for patients with pancreatic cancer. Therefore, there is an urgent need for effective pancreatic cancer treatment strategies. At present, targeting the autophagic pathway is regarded as a promising new strategy for cancer treatment. Danthron (1,8-dihydroxyanthrquinone), a component from Rheum palmatum L. (polygonaceae), has several biological activities. However, the inhibition of autophagy by danthron has never been recognized, previously.Here we find that danthron may prevent autophagy, inhibit proliferation and induce apoptosis in pancreatic cancer cells in vitro. Autophagy induced by doxorubicin plays a protective role in pancreatic cancer cells and inhibition of autophagy by chloroquine or silencing autophagy protein 5 (Atg5) may chemosensitize pancreatic cancer cell lines to doxorubicin. Similarly, inhibition of autophagy by danthron also enhances toxicity of doxorubicin to pancreatic cancer cells. These results indicate that danthron has an anticancer effect and can sensitize the chemotherapeutic effect of doxorubicin on pancreatic cancer cells. These findings also suggest that inhibition of autophagy may be an effective way to promote the chemotherapy of pancreatic cancer.

Antitumor activity of RT2 peptide derived from crocodile leukocyte peptide on human colon cancer xenografts in nude mice

RT2, derived from the leukocyte peptide of Crocodylus siamensis, can kill human cervical cancer cells via apoptosis induction, but no evidence has shown in vivo. In this study, we investigated the antitumor effect of RT2 on human colon cancer xenografts in nude mice. Twenty-four mice were injected subcutaneously with human colon cancer HCT 116 cells. Eleven days after cancer cell implantation, the mice were treated with intratumoral injections of phosphate buffered saline (PBS) or RT2 (0.01, 0.1, and 1 mg/mouse) once every 2 days for a total of 5 times. The effect of a 10-day intratumoral injection of RT2 on body weight, biochemical, and hematological parameters in BALB/c mice showed no significant difference between the groups. Tumor volume showed a significant decrease only in the treatment group with RT2 (1 mg/mouse) at day 6 (P < .05), day 8 (P < .01), and day 10 (P < .01) after the first treatment. The protein expression levels of cleaved poly (ADP-ribose) polymerase (PARP), apoptosis-inducing factor (AIF), and the p53 tumor suppressor protein (p53) in xenograft tumors increased after treatment with RT2 (1 mg/mouse) compared to those in the PBS-injected group. Moreover, RT2 increased the expression of Endo G and Bcl-2 family proteins. Therefore, the peptide RT2 can inhibit tumor growth via the induction of apoptosis in an in vivo xenograft model.

Anesthetic agent etiomidate induces apoptosis in N2a brain tumor cell line

The present study identified the cytotoxic effects of etomidate on the N2a neuroblastoma cell line. Etomidate induced apoptosis in N2a cells in a concentration-dependent manner, which was confirmed by western blotting and flow cytometry. Phase contrast microscopy was used to analyze the effect of etomidate on morphological characteristics. The number of the apoptotic cells was increased and confirmed by DAPI and PI staining, which served as a characteristic hallmark of apoptosis. Additionally, etomidate led to loss of mitochondrial membrane potential and resulted in the generation of reactive oxygen species in N2a cells. The western blot analysis revealed that N2a cells treated with etomidate had a significant modulation of pro-apoptotic proteins, includingpoly ADP-ribose polymerase (PARP), cleaved PARP, caspase-9 and procaspase-3. In conclusion, the present study determined that etomidate induced cytotoxic and apoptotic effects in N2a brain tumor cells in vitro.

Betulinic acid exerts potent antitumor effects on paclitaxel-resistant human lung carcinoma cells (H460) via G2/M phase cell cycle arrest and induction of mitochondrial apoptosis

Betulinic acid is a pentacyclic plant compound obtained from the bark of white birch trees and has been demonstrated to exhibit notable pharmacological properties. In the present study, the anticancer potential of betulinic acid on paclitaxel-resistant lung cancer cell line (H460) was evaluated. Cell viability was evaluated by an MTT assay, and a clonogenic assay was performed to assess the effects on cancer cell colony formation. DAPI staining using fluorescence microscopy and flow cytometry were employed to evaluate the effects of betulinic acid on apoptosis. The effects of betulinic acid on the cell cycle and mitochondrial membrane potential were also evaluated by flow cytometry. The effects of betulinic acid on the protein expression of B-cell lymphoma-2 (Bcl-2)/Bcl-2-associated X (Bax) were evaluated by western blot analysis. The results of the present study indicated that the half-maximal inhibitory concentration value of betulinic acid on paclitaxel-resistant H460 lung cancer cells was 50 µM. The treatment with betulinic acid was able to inhibit the colony formation potential in a dose-dependent manner. A lower cytoxicity by betulinic acid against normal human epithelial FR2 cells was observed compared with H460 cells. The betulinic acid exerted anticancer activity via the induction of apoptosis by regulating the Bcl-2/Bax signaling pathway. Additionally, treatment with betulinic acid resulted in cell cycle arrest of paclitaxel-resistant lung cancer H460 cells at the G2/M phase. Betulinic acid was also reported to cause reductions in the mitochondrial membrane potential in a dose-dependent manner. In conclusion, the results of the present study indicated that betulinic acid may be a useful drug candidate for the management of drug-resistant lung cancer.

Fucosterol exhibits selective antitumor anticancer activity against HeLa human cervical cell line by inducing mitochondrial mediated apoptosis, cell cycle migration inhibition and downregulation of m-TOR/PI3K/Akt signalling pathway

Cervical cancer greatly contributes to cancer-associated mortalities worldwide. The growing incidence of cervical cancer is of primary concern, and has signaled the need for multiple treatment options. Despite preliminary responses to chemotherapy and/or surgical interventions, the tumors consistently relapse. Previously, natural products gained attention for their diverse bioactivities, which include however are not limited to, neuroprotective, antimicrobial and anticancer effects. The present study evaluated the anticancer activity of fucosterol against a panel of human cancer cell lines. Results indicated that fucosterol exhibited selective inhibitory activity against human HeLa cervical cancer cell line with an IC₅₀ of 40 µM. Fucosterol also induced apoptosis in HeLa cells and prompted reactive oxygen species mediated alterations in mitochondrial membrane potential. It triggered cell cycle arrest of HeLa cells at G2/M check point and exerted inhibitory effects on cell migration. The activation of the phosphoinositide-3-kinase (PI3K)/AKT Serine/Threonine Kinase 1 (AKT)/mechanistic target of Rapamycin (mTOR) pathway is important in cancer tumorigenesis, progression and chemotherapy resistance. The results demonstrated that fucosterol significantly inhibited the expression levels of key proteins of the PI3K/Akt/mTOR signaling pathway. Overall, the results of the present study suggest that fucosterol may prove beneficial in the management of cervical cancer.

Genistein induced anticancer effects on pancreatic cancer cell lines involves mitochondrial apoptosis, G0/G1cell cycle arrest and regulation of STAT3 signalling pathway

BACKGROUND

Genistein is a natural flavonoid that has been reported to exhibit anticancer effects against different types of cancers which include, but are not limited to, breast and oral squamous cell carcinoma.

PURPOSE

The present study was designed to evaluate the anticancer effects of the natural flavonoid genistein against pancreatic cancer cell lines and to explore the underlying mechanism.

METHODS

Antiproliferative activity was investigated by MTT assay. Apoptosis was detected by DAPI and annexin V/PI staining. DNA damage was assessed by comet assay. Reactive oxygen species (ROS) and reduction of mitochondrial membrane potential (MMP) were determined by flow cytometry. Cell migration was examined by wound healing assay. Protien expressions were determined by western blotting.

RESULTS

Antiproliferative assay revealed that genistein reduced the cell viability of pancreatic cancer cells in a dose dependent manner with an IC₅₀ of 20 and 25 µM against Mia-PaCa2 and PANC-1 cancer cell lines respectively. However, its antiproliferative effects were less pronounced against non-cancerous pancreatic ductal epithelial cell line (H6C7) as evident from the IC₅₀ of 120 µM. Genistein induced significant morphological changes in pancreatic cancer cells and triggered cell cycle arrest in G₀/G₁ phase. DAPI staining and flow cytometric analysis revealed that genistein induced apoptosis in a dose dependent manner through generation of substantial amounts of ROS and reduction of MMP. However, treatment of the pancreatic cancer with genistein and ascorbic acid could abrogate the effects of genistein on cell viability. Protien expression analysis revealed that genistein upregulated cytosolic cytochrome c, Bax, cleaved Caspase-3 and cleaved caspase-9 expressions with concomitant downregulation of Bcl-2 expression. Moreover, genistein inhibited the phosphorylation of signal transducer and activator of transcription STAT3 proteins and downregulated the expression of survivin, cyclin D1 and ALDH1A1 in Mia-PaCa2 cells in a dose dependent manner. Interestingly, genistein could inhibit the cell migration potential of the Mia-PaCa2 cells which was further associated with the downregulation of metalloproteinases (MPP-2 and MPP-9).

CONCLUSION

Taken together, we propose that genistein exerts anticancer activity in pancreatic cancer cells through induction of ROS mediated mitochondrial apoptosis, cell cycle arrest and regulation of STAT3 and may therefore prove beneficial in the management of pancreatic cancers cancer.

Anticancer activity of 23,24-dihydrocucurbitacin B against the HeLa human cervical cell line is due to apoptosis and G2/M cell cycle arrest

Cervical cancer is one of the primary causes of cancer-associated mortality worldwide. Due to the increasing incidence of cervical cancer, multiple treatment options are required. Initial responses to chemotherapy and surgical interventions are generally positive, however patients often experience relapse and tumor recurrence. Currently, the effects of cucurbitacins on different types of cancer are being investigated, as they exhibit a wide variety of bioactivities. The anticancer activity of the cucurbitacin 23,24-dihydrocucurbitacin B against a panel of human cervical cancer cell lines was investigated in the current study. Cell viability was determined using an MTT assay and apoptosis was detected using DAPI staining. The proportion of apoptotic cells, cell cycle distribution, mitochondrial membrane potential (ΔΨ_m) and reactive oxygen species (ROS) levels were estimated using flow cytometry. Protein expression was determined using western blot analysis. The results of the current study indicated that 23,24-dihydrocucurbitacin B inhibited the viability of human cervical cancer cell lines and had an IC₅₀ of 40-60 µM. However, its cytotoxic effects were much less pronounced in normal epithelial fr2 and HerEpiC cells, where it had an IC₅₀ of 125 µM. The underlying mechanisms of this were further studied and the results demonstrated that 23,24-dihydrocucurbitacin B induced apoptosis in HeLa cells and caused ROS-mediated shifts in the ΔΨ_m. Additionally, it caused the cell cycle arrest of HeLa cells at the G₂/M checkpoint. The phosphoinositide 3 kinase/protein kinase B/mechanistic target of rampamycin (PI3K/AKT/mTOR) cascade may serve an important role in cancer tumorigenesis, progression and resistance to chemotherapy. The results indicated that 23,24-dihydrocucurbitacin B significantly decreased the expression of important proteins in the PI3K/Akt/mTOR cascade. Taken together, these results suggest that 23,24-dihydrocucurbitacin B may be novel method of treating cervical cancer.

Bufalin induced apoptosis in SCC‑4 human tongue cancer cells by decreasing Bcl‑2 and increasing Bax expression via the mitochondria‑dependent pathway

The aim of the present study was to investigate the cytotoxic effects of bufalin on SCC-4 human tongue cancer cells. Cell morphological changes and viability were examined using phase contrast microscopy and flow cytometry, respectively. The results indicated that bufalin induced morphological changes and reduced total viable cells. Apoptotic cell death was analyzed by DAPI staining and DNA gel electrophoresis; the results revealed that bufalin induced cell apoptosis. Levels of reactive oxygen species (ROS), Ca²⁺, nitric oxide (NO) and mitochondrial membrane potential (ΔΨ_m) were measured by flow cytometry, and bufalin was observed to increase Ca²⁺ and NO production, decrease the ΔΨ_m and reduce ROS production in SCC-4 cells. In addition, western blotting was performed to detect apoptosis-associated protein expression. The results demonstrated that bufalin reduced the expression of the anti-apoptotic protein B-cell lymphoma 2 (Bcl-2) and increased the expression of the pro-apoptotic protein, Bcl-2-associated X protein. However, bufalin treatment also increased the expression of other apoptosis-associated proteins such as apoptosis-inducing factor and endonuclease G in SCC-4 cells. Based on these findings, bufalin may induce apoptotic cell death via mitochondria-dependent pathways in human tongue cancer SCC-4 cells.

Anticancer Activity of Pterostilbene in Human Ovarian Cancer Cell Lines

BACKGROUND Epithelial ovarian cancer is a major cause of mortality in women and one of the most common gynecologic disorders. Pterostilbene (PTS), a trans-3,5-dimethoxy-4'-hydroxystilbene, was chosen for this work due to its reported effectiveness as a chemotherapeutic agent in cancer studies. In this work, we studied underlying molecular mechanisms of PTS treatment in various ovarian cancer cell lines such as OVCAR8, OV1063, IGROV-1, and SKOV3. MATERIAL AND METHODS We used the cytometric bead array (CBA) method and real-time PCR analysis to analyze the secretion level of tumor necrosis factor alpha (TNF-α) and to measure the TNF-α mRNA expression. NF-kappa B (NF-κB) promoter analysis, Western blot analysis, electrophoresis mobility shift assay (EMSA), and immunostaining analyses were performed to measure the NF-κB activity and other relative proteins levels. RESULTS The PTS treatment decreased the release of TNF-α in IGROV-1 ovarian cancer cells. It also showed significant inhibitory effect on nuclear NF-κB p50, and NF-κB p65 protein levels. CONCLUSIONS From the results obtained, we suggest that PTS has the potential to treat ovarian cancer by reducing the level of TNF-α cytokine and to have a limited effect on NF-κB, AKT, and ERK signaling pathways.

ANTICANCER ACTIVITY OF 5, 7-DIMETHOXYFLAVONE AGAINST LIVER CANCER CELL LINE HEPG2 INVOLVES APOPTOSIS, ROS GENERATION AND CELL CYCLE ARREST

BACKGROUND

Flavonoids are considered potential anticancer agents owing to their properties to interact with a diversity of cellular entities. Among flavonoids, methylated flavones are more efficient anticancer agents due to their higher stability in vivo. The purpose of the present study was, therefore, to evaluate the anticancer effect of methylated natural flavonoid 5, 7-dimethoxyflavone (5, 7-DMF).

MATERIALS AND METHODS

MTT assay was used to determine the anticancer activity and IC₅₀ of 5, -DMF). Cell viability, cell cycle distribution, reactive oxygen species (ROS) and mitochondrial membrane potential (ΔΨm) were carried out by flow cytometry. Apoptosis was studied by DAPI staining.

RESULTS

MTT assay revealed that the molecule reduced the cell viability of HepG2 cancer cells. The IC₅₀ of 5, 7-DMF was found to be 25 µM. Our result indicated that 5, 7-DMF triggered production of ROS and significantly reduced ΔΨ_m . It also leads to arrest of HepG2 cells in Sub-G1 stage of cell cycle, and ultimately induced apoptosis in a concentration-dependent manner, as indicated by DAPI staging. Additionally, 5, 7-DMF also reduced the colony forming potential of the HepG2 cells concentration dependently.

CONCLUSION

Taken together, we conclude that 5, 7-DMF induces cell death via ROS generation, cell cycle arrest and apoptosis, and, therefore, may prove beneficial in the treatment of liver cancer.

3',5-dihydroxy-3,4',7-trimethoxyflavone-induces ER-stress-associated HCT-116 programmed cell death via redox signaling

Quercetin, a well cognized bioactive flavone possessing great medicinal value, has limited usage. The rapid gastrointestinal digestion of quercetin is also a major obstacle for its clinical implementation due to low bioavailability and poor aqueous solubility. 3',5-dihydroxy-3,4',7-trimethoxyflavone (DTMF), a novel semi-synthetic derivative of quercetin, is known to modulate several biological activities. Therefore, in the present study we examined the cytotoxic mechanism of DTMF in concentration-dependent manner (25, 50, and 100μM; 24h) against HCT-116 human colon carcinoma cells. The cytotoxic potential of DTMF was characterized based on deformed cell morphology, increased ROS accumulation, loss of mitochondrial membrane potential (ΔѰm), increased mitochondrial mass, chromatin condensation, and typical DNA-fragmentation in HCT-116 cells. The results showed that DTMF-induced enhanced ROS production at higher concentration (100μM) as evidenced by upregulated expression of ER stress and apoptotic proteins with concomitant increase in PERK, CHOP, and JNK levels, when compared to N-acetyl cysteine (NAC, ROS inhibitor) treated HCT-116 cells, which depicts that DTMF might act as a crucial mediator of apoptosis signaling. Collectively, our results suggest that DTMF stimulates ROS-mediated oxidative stress, which in turn induces PERK-CHOP and JNK pathway of apoptosis to promote HCT-116 cell death.

Antitumor effects of deguelin on H460 human lung cancer cells in vitro and in vivo: Roles of apoptotic cell death and H460 tumor xenografts model

Deguelin, a naturally occurring rotenoid of the flavonoid family, is known to be an Akt inhibitor, to have chemopreventive activities and anti-tumor effect on several cancers. In this study, investigation to elucidate the effect of deguelin on apoptotic pathways in human lung cancer cells and on the anti-tumor effect in lung cancer xenograft nu/nu mice was performed. In vitro studies, found that deguelin induced cell morphological changes, and decreased the percentage of viability through the induction of apoptosis in H460 lung cancer cells. Deguelin triggered apoptosis in H460 cells was also confirmed by DAPI staining, DNA gel electrophoresis, and Annexin V-FITC staining and these effects are dose-dependent manners. It was also found that deguelin promoted the Ca²⁺ production and activation of caspase-3 but decreased the level of ΔΨ_m in H460 cells. Western blots indicated that the protein levels of cytochrome c, AIF, and pro-apoptotic Bax and Bak protein were increased, but the anti-apoptotic Bcl-2 and Bcl-x were decreased that may have led to apoptosis in H460 cells after exposure to deguelin. It was also confirmed by confocal laser microscope examination that deguelin promoted the release of AIF from mitochondria to cytosol. In vivo studies, found that in immunodeficient nu/nu mice bearing H460 tumor xenografts showed that the deguelin significantly suppressed tumor growth. Deguelin might be a potential therapeutic agent for the treatment of lung cancer in the future. This finding might fully support a critical event for deguelin via induction of apoptotic cell death and H460 tumor xenografts model against human lung cancer. © 2015 Wiley Periodicals, Inc. Environ Toxicol 32: 84-98, 2017.