Anticancer activity of Bacopa monnieri through apoptosis induction and mitophagy-dependent NLRP3 inflammasome inhibition in oral squamous cell carcinoma.

BACKGROUND: Bacopa monnieri (BM) is traditionally used in human diseases for its antioxidant, anti-inflammatory and neuroprotective effects. However, its anticancer potential has been poorly understood. AIM: The aim of this study was to explore the detailed anticancer mechanism of BM against oral cancer and to identify the bioactive BM fraction for possible cancer therapeutics. RESULTS: We performed bioactivity-guided fractionation and identified that the aqueous fraction of the ethanolic extract of BM (BM-AF) had a potent anticancer potential in both in vitro and in vivo oral cancer models. BM-AF inhibited cell viability, colony formation, cell migration and induced apoptotic cell death in Cal33 and FaDu cells. BM-AF at low doses promoted mitophagy and BM-AF mediated mitophagy was PARKIN dependent. In addition, BM-AF inhibited arecoline induced reactive oxygen species production in Cal33 cells. Moreover, BM-AF supressed arecoline-induced NLR family pyrin domain containing 3 (NLRP3) inflammasome activation through mitophagy in Cal33 cells. The in vivo antitumor effect of BM-AF was further validated in C57BL/6J mice through a 4-nitroquinolin-1-oxide and arecoline-induced oral cancer model. The tumor incidence was significantly reduced in the BM-AF treated group. Further, data obtained from western blot and immunohistochemistry analysis showed increased expression of apoptotic markers and decreased expression of inflammasome markers in the tongue tissue obtained from BM-AF treated mice in comparison with the non-treated tumor bearing mice. CONCLUSION: In conclusion, BM-AF exhibited potent anticancer activity through apoptosis induction and mitophagy-dependent inhibition of NLRP3 inflammasome activation in both in vitro and in vivo oral cancer models. Moreover, we have investigated apoptosis and mitophagy-inducing compounds from this plant extract having anticancer activity against oral cancer cells.

A Review on the Current Status of Homeopathy in the Clinical Manage-ment of Cancer.

Homeopathy is a widely practiced alternate system of medicine around the world that employs small doses of various medicines to promote auto-regulation and self-healing. It is among the most commonly used alternative approaches in cancer and other diseases and alternative therapeutic systems. It is widely used as palliative and as supportive therapy in cancer patients. Few cases have been reported on patients using homeopathy after surgery, radiotherapy, and chemotherapy, generally for overcoming side effects. The dose of Homoeopathic medicines and their mechanism of action in cancer has also been documented, while clinical trials on the effects of Homoeopathy in cancer treatment are rare. It is found that the anticancer potential of homeopathic medicines is reported for different cancer types, which show their efficacy through apoptosis and immune system modulation. Homeopathic treatment is an add-on to conventional therapy, with almost no interaction with the conventional drugs due to the small dose, and is largely attributed to improving lives by providing symptomatic relief, increasing survival time and boosting patient immunity. This review explores the accountability of the homeopathic system of medicine by highlighting some of the most commonly used homeopathic drugs for different types of cancers.

Vitamin D in autophagy signaling for health and diseases: Insights on potential mechanisms and future perspectives.

Vitamin D regulates the pleiotropic effect to maintain cellular homeostasis and epidemiological evidence establishes an association between vitamin D deficiency and various human diseases. Here, the role of autophagy, the cellular self-degradation process, in vitamin D-dependent function is documented in different cellular settings and discussed the molecular aspects for treating chronic inflammatory, infectious diseases, and cancer. Vitamin D activates autophagy through a genomic and non-genomic signaling pathway to influence a wide variety of physiological functions of different body organs along with bone health and calcium metabolism. Moreover, it induces autophagy as a protective mechanism to inhibit oxidative stress and apoptosis to regulate cell proliferation, differentiation, and immune modulation. Furthermore, vitamin D and its receptor regulate autophagy signaling to control inflammation and host immunity by activating antimicrobial defense mechanisms. Vitamin D has been revealed as a potent anticancer agent and induces autophagy to increase the response to radiation and chemotherapeutic drugs for potential cancer therapy. Increasing vitamin D levels in the human body through timely exposure to sunlight or vitamin D supplements could activate autophagy as part of the homeostasis mechanism to prevent multiple human diseases and aging-associated dysfunctions.

Dietary polyphenols in chemoprevention and synergistic effect in cancer: Clinical evidences and molecular mechanisms of action.

BACKGROUND: Epidemiological studies has revealed that a diet rich in fruits and vegetables could lower the risk of certain cancers. In this setting, natural polyphenols are potent anticancer bioactive compounds to overcome the non-target specificity, undesirable cytotoxicity and high cost of treatment cancer chemotherapy. PURPOSE: The review focuses on diverse classifications of the chemical diversity of dietary polyphenol and their molecular targets, modes of action, as well as preclinical and clinical applications in cancer prevention. RESULTS: The dietary polyphenols exhibit chemo-preventive activity through modulation of apoptosis, autophagy, cell cycle progression, inflammation, invasion and metastasis. Polyphenols possess strong antioxidant activity and control multiple molecular events through activation of tumor suppressor genes and inhibition of oncogenes involved in carcinogenesis. Numerous in vitro and in vivo studies have evidenced that these dietary phytochemicals regulate critical molecular targets and pathways to limit cancer initiation and progression. Moreover, natural polyphenols act synergistically with existing clinically approved drugs. The improved anticancer activity of combinations of polyphenols and anticancer drugs represents a promising perspective for clinical applications against many human cancers. CONCLUSION: The anticancer properties exhibited by dietary polyphenols are mainly attributed to their anti-metastatic, anti-proliferative, anti-angiogenic, anti-inflammatory, cell cycle arrest, apoptotic and autophagic effects. Hence, regular consumption of dietary polyphenols as food or food additives or adjuvants can be a promising tactic to preclude adjournment or cancer therapy.

PEG-PEI-modified gated N-doped mesoporous carbon nanospheres for pH/NIR light-triggered drug release and cancer phototherapy.

A novel hybrid drug carrier has been designed, taking N-doped mesoporous carbon (NMCS) as the core and PEG-PEI as the outer shell. NMCS was functionalized with a photocleavable nitrobenzyl-based linker following a click reaction. Gemcitabine was loaded into NMCS prior to the functionalization via π-π stacking interactions. NIR and the pH-responsive behavior of NMCS-linker-PEG-PEI bestow the multifunctional drug carrier with the controlled release of gemcitabine triggered by dual stimuli. The NMCS core upconverts NIR light to UV, which is absorbed by a photosensitive molecular gate and results in its cleavage and drug release. Further, NMCS converts NIR to heat, which deforms the outside polymer shell, thus triggering the drug release process. The release can be promptly arrested if the NIR source is switched off. A promising gemcitabine release of 75% has been achieved within 24 h under the dual stimuli of pH and temperature. NMCS-linker-PEG-PEI produced reactive oxygen species (ROS), which were verified in FaDu cells using flow cytometry. In vitro experiments showed that the NMCS-linker-PEG-PEI-GEM hybrid particle can induce synergistic therapeutic effects in FADU cells when exposed to the NIR light.

Apoptosis and autophagy modulating dietary phytochemicals in cancer therapeutics: Current evidences and future perspectives.

The global incidence of cancer and cancer-related mortality is expected to rise in recent years despite advancements in cancer diagnosis and therapeutics. Increasing evidences of decrypting molecular mechanisms underlying cancer progression have commanded the tremendous development of synthetic anticancer drugs. With limitations in the current conventional cancer therapeutic approaches, the non-nutritive dietary phytochemicals have emerged as potent modulators of apoptosis and autophagy associated key signaling pathways in various cancer cells. The dynamic regulation of apoptosis and autophagy by phytochemicals in cancer are identified as promising therapeutic candidates with minimal cytotoxicity and enhanced biological activity. Dietary phytochemicals and their synthetic analogs have exhibited potency in the modulation of apoptosis and autophagy in several cancer cells as individuals or in combination with pre-existing FDA (Food and Drug Administration) approved anticancer drugs. In the current generation of medical science, developing precision and personalized medicine and their consumption as food supplements will hold high prevalence in cancer therapeutics. Hence understating the impact of dietary phytochemicals on human health and their molecular mechanism will thrive a new horizon in cancer therapeutics. Hence, this review has emphasized the role of apoptotic/autophagy modulating dietary phytochemicals in cancer therapy, their preclinical and clinical applications and the future direction of enhanced nano-formulation for better clinical efficacy.

Bacopa monnieri inhibits apoptosis and senescence through mitophagy in human astrocytes.

Benzo[a]pyrene (B[a]P), a polycyclic aromatic hydrocarbon, is a potent neurotoxic agent that is responsible for impaired neuronal development and is associated with aging. Here, it was demonstrated that extracts of Bacopa monnieri (BM), a traditional Ayurvedic medicine, diminished the B[a]P-induced apoptosis and senescence in human astrocytes. BM was demonstrated to protect the immortalized primary fetal astrocytes (IMPHFA) from B[a]P-induced apoptosis and senescence by reducing the damaged mitochondria that produced reactive oxygen species (ROS). Furthermore, it was shown that B[a]P-triggered G2 arrest could be altered by BM, thus indicating that BM could reverse the cell cycle arrest and mediate a normal cell cycle in IMPHFA cells. In addition, the lifespan of Caenorhabditis elegans was assessed, which confirmed these effects in the presence of BM, compared to the B[a]P-treated group. Furthermore, the anti-senescence and anti-apoptotic activities of BM were observed to be mediated through the protective effect of mitophagy, and inhibition of mitophagy could not protect the astrocytes from mitochondrial ROS-induced apoptosis and senescence in BM-treated cells. Moreover, it was revealed that BM induced Parkin-dependent mitophagy to exert its cytoprotective activity in IMPHFA cells. In conclusion, the anti-senescence and anti-apoptotic effects of BM in astrocytes could combat pollution and aging-related neurological disorders.

Terminalia bellirica extract induces anticancer activity through modulation of apoptosis and autophagy in oral squamous cell carcinoma.

Terminalia bellirica (TB) has been used in traditional Indian medical system, Ayurveda. However, the mechanism underlying the efficacy of the TB extract against oral squamous cell carcinoma (OSCC) is yet to be explored. The present study established a connecting link between the TB extract induced apoptosis and autophagy in relation to reactive oxygen species (ROS). Our study revealed, that gallic acid in the TB extract possess a strong free radical scavenging capacity contributing towards the selective anti-proliferative activity. Furthermore, TB extract markedly enhanced the accumulation of ROS that facilitated mitochondrial apoptosis through DNA damage, indicating ROS as the vital component in regulation of apoptosis. This effect was effectively reversed by the use of a ROS scavenger, N-acetyl cysteine (NAC). Moreover, it was observed to induce autophagy; however, it attenuated the autophagosome-lysosome fusion in Cal33 cells without altering the lysosomal activity. Pharmacological inhibitors of autophagy, namely, 3-methyladenine and chloroquine, were demonstarated to regulate the stage-specific progression of autophagy post treatment with the TB extract, favouring subsequent activation of apoptosis. These findings revealed, presence of gallic acid in TB extract below NOAEL value causes oxidative upset in oral cancer cells and promote programmed cell death which has a potential therapeutic value against oral squamous cell carcinoma.

Abrus agglutinin suppresses human hepatocellular carcinoma in vitro and in vivo by inducing caspase-mediated cell death.

AIM: Abrus agglutinin (AGG) from the seeds of Indian medicinal plant Abrus precatorius belongs to the class II ribosome inactivating protein family. In this study we investigated the anticancer effects of AGG against human hepatocellular carcinoma in vitro and in vivo. METHODS: Cell proliferation, DNA fragmentation, Annexin V binding, immunocytofluorescence, Western blotting, caspase activity assays and luciferase assays were performed to evaluate AGG in human liver cancer cells HepG2. Immunohistochemical staining and TUNEL expression were studied in tumor samples of HepG2-xenografted nude mice. RESULTS: AGG induced apoptosis in HepG2 cells in a dose- and time-dependent manner. AGG-treated HepG2 cells demonstrated an increase in caspase 3/7, 8 and 9 activities and a sharp decrease in the Bcl-2/Bax ratio, indicating activation of a caspase cascade. Co-treatment of HepG2 cells with AGG and a caspase inhibitor or treatment of AGG in Bax knockout HepG2 cells decreased the caspase 3/7 activity in comparison to HepG2 cells exposed only to AGG. Moreover, AGG decreased the expression of Hsp90 and suppressed Akt phosphorylation and NF-κB expression in HepG2 cells. Finally, AGG treatment significantly reduced tumor growth in nude mice bearing HepG2 xenografts, increased TUNEL expression and decreased CD-31 and Ki-67 expression compared to levels observed in the untreated control mice bearing HepG2 cells. CONCLUSION: AGG inhibits the growth and progression of HepG2 cells by inducing caspase-mediated cell death. The agglutinin could be an alternative natural remedy for the treatment of human hepatocellular carcinomas.

Antitumor effect of culinary-medicinal oyster mushroom, Pleurotus ostreatus (Jacq.: Fr.) P. Kumm., derived protein fraction on tumor-bearing mice models.

Previously, we reported the in vitro anticancer and immunomodulatory effect of a protein fraction designated as Cibacron blue affinity purified protein (CBAEP) obtained from the culinary-medicinal oyster mushroom, Pleurotus ostreatus. In the present study, we investigated the in vivo antitumor potential of CBAEP in different tumor-bearing mice models and studied the detailed mechanism of tumor regression in Dalton lymphoma (DL)-bearing mice. The lethal dose (LD50) of CBAEP was found to be 55 mg/kg body weight and sublethal doses (5 mg/kg and 10 mg/kg body weight) showed a prolonged tumor survival time in DL, Sarcoma-180, and B16F0 melanoma tumor-bearing mice. Further, CBAEP reduced about 35.68 and 51.43% DL cell growth in 5 and 10 mg/kg body weight, respectively. The in vivo CBAEP treatment showed an apoptotic feature as demonstrated in morphological study and sub-G0/G1 population in cell cycle and Western blot of DL cells. CBAEP also activated immunosuppression condition in DL tumor-bearing host. It also stimulated immune cells in the presence of nonspecific immunostunulator (LPS and ConA) ex vivo as well as enhanced Th1 response with production of TNF-α, IFN-γ, and IL-2. Moreover, it activated tumor-associated macrophages and NK cells. The present findings revealed the potent antitumor property of CBAEP, which might help in developing a new anticancer drug.

Anti-tumor and immunomodulating effects of Pleurotus ostreatus mycelia-derived proteoglycans.

Pleurotus ostreatus is one of the widely cultivated edible mushrooms. Water-soluble proteoglycan fractions from P. ostreatus mycelia were purified by alcohol-precipitation, ion exchange and followed by gel permeation (Sephadex G-100) chromatography. Three neutral fractions were found, which had polysaccharide to protein ratios 14.2, 26.4 and 18.3, respectively. These fractions were tested for in vitro and in vivo immunomodulatory and anticancer effects on Sarcoma-180-bearing mouse model. In vivo injection of proteoglycans to Sarcoma-180-bearing mice decreased the number of tumor cells and cell cycle analysis showed that most of the cells were found to be arrested in pre-G(0)/G(1) phase of cell cycle. All of the three proteoglycans elevated mouse natural killer (NK) cell cytotoxicity and stimulated macrophages to produce nitric oxide. The Fourier transform infra red (FTIR) spectra suggested the presence of beta-glycosidic bond in all the fractions. Fraction I strongly interacted with glucose/mannose-specific lectin Concanavalin A (ConA), indicating the presence of large number of terminal sugar with glucose/mannose. Thus, the three neutral proteoglycans derived from the mushroom (P. ostreatus) mycelia could be used as immunomodulators and anti cancer agents.