Bitter melon juice-intake modulates glucose metabolism and lactate efflux in tumors in its efficacy against pancreatic cancer

A Mechanistic Review on Therapeutic Potential of Medicinal Plants and their Pharmacologically Active Molecules for Targeting Metabolic Syndrome

Metabolic syndrome (MetS) therapy with phytochemicals is an emerging field of study with therapeutic potential. Obesity, insulin resistance, high blood pressure, and abnormal lipid profiles are all components of metabolic syndrome, which is a major public health concern across the world. New research highlights the promise of phytochemicals found in foods, including fruits, vegetables, herbs, and spices, as a sustainable and innovative method of treating this illness. Anti-inflammatory, antioxidant, and insulin-sensitizing qualities are just a few of the many positive impacts shown by bioactive substances. Collectively, they alleviate the hallmark symptoms of metabolic syndrome by modulating critical metabolic pathways, boosting insulin sensitivity, decreasing oxidative stress, and calming chronic low-grade inflammation. In addition, phytochemicals provide a multimodal strategy by targeting not only adipose tissue but also the liver, skeletal muscle, and vascular endothelium, all of which have a role in the pathogenesis of MetS. Increasing evidence suggests that these natural chemicals may be useful in controlling metabolic syndrome as a complementary treatment to standard medication or lifestyle changes. This review article emphasizes the therapeutic potential of phytochemicals, illuminating their varied modes of action and their ability to alleviate the interconnected causes of metabolic syndrome. Phytochemical-based interventions show promise as a novel and sustainable approach to combating the rising global burden of metabolic syndrome, with the ultimate goal of bettering public health and quality of life.

Phytochemicals as Regulators of Tumor Glycolysis and Hypoxia Signaling Pathways: Evidence from In Vitro Studies

The full understanding of the complex nature of cancer still faces many challenges, as cancers arise not as a result of a single target disruption but rather involving successive genetic and epigenetic alterations leading to multiple altered metabolic pathways. In this light, the need for a multitargeted, safe and effective therapy becomes essential. Substantial experimental evidence upholds the potential of plant-derived compounds to interfere in several important pathways, such as tumor glycolysis and the upstream regulating mechanisms of hypoxia. Herein, we present a comprehensive overview of the natural compounds which demonstrated, in vitro studies, an effective anticancer activity by affecting key regulators of the glycolytic pathway such as glucose transporters, hexokinases, phosphofructokinase, pyruvate kinase or lactate dehydrogenase. Moreover, we assessed how phytochemicals could interfere in HIF-1 synthesis, stabilization, accumulation, and transactivation, emphasizing PI3K/Akt/mTOR and MAPK/ERK pathways as important signaling cascades in HIF-1 activation. Special consideration was given to cell culture-based metabolomics as one of the most sensitive, accurate, and comprising approaches for understanding the response of cancer cell metabolome to phytochemicals.

Comparative Pre-clinical Efficacy of Chinese and Indian Cultivars of Bitter Melon (Momordica charantia) against Pancreatic Cancer

Given the high rates of incidence and mortality associated with pancreatic cancer (PanC), there is a need to develop alternative strategies to target PanC. Recent studies have demonstrated that fruits of bitter melon (Momordica charantia) exhibit strong anticancer efficacy against PanC. However, the comparative effects of different bitter melon varieties have not been investigated. This has important implications, given that several bitter melon cultivars are geographically available but their differential effects are not known; and that on a global level, individuals could consume different bitter melon varieties sourced from different cultivars for anti-PanC benefits. Considering these shortcomings, in the present study, comparative pre-clinical anti-PanC studies have been conducted using lyophilized-juice and aqueous-methanolic extracts of the two most widely consumed but geographically diverse bitter melon varieties (Chinese [bitter melon juice; BMJ] and Indian [bitter melon extract; BME] variants). We observed that both BMJ and BME possess comparable efficacy against PanC growth and progression; specifically, these preparations have the potential to (a) inhibit PanC cell proliferation and induce cell death; (b) suppress PanC tumor growth, proliferation, and induce apoptosis; (c) restrict capillary tube formation by human umbilical vein endothelial cells, and decrease angiogenesis in PanC tumor xenografts. Thus, given the comparable pre-clinical anti-PanC efficacy of bitter melon cultivars, the geographical non-availability of a certain cultivar should not be a limiting factor in selecting a variant for moving forward for future clinical use/clinical trials either as a preventive or a therapeutic alternative for targeting PanC.

A pharmacognostic approach for mitigating pancreatic cancer: emphasis on herbal extracts and phytoconstituents

Background

Pancreatic cancer is studied as one of the most lethal cancers with currently no control of its lethality, mainly due to its late diagnosis and lack of foolproof treatment processes. Despite continuous efforts being made in looking for therapies to deal with cancer, it keeps on being a labyrinth for the researchers. Efforts like discovering new treatment options, repurposing existing drugs, are continuously made to deal with this cancer.

Main body

With the urge to get answers and the fact that nature has all roots of therapeutics, efforts are made in the direction of finding those answers for providing ministrations for pancreatic cancer from plant products. Plant products are used as treatment options either directly in the form of extracts or an alternative to them is individual phytochemicals that are either isolated from the plants or are commercially synthesized for various purposes. In this review, we put forward such pharmacognostic initiatives made in combating pancreatic cancer, focusing mainly on plant extracts and various phytochemicals; along with the mechanisms which they triggered to fulfill the need for cytotoxicity to pancreatic cancer cells (in vitro and in vivo).

Conclusion

This study will thus provide insights into new combination therapy that can be used and also give a clue on which plant product and phytoconstituent can be used in dealing with pancreatic cancer.

Graphical abstract

Synergism between SLC6A14 blockade and gemcitabine in pancreactic cancer: a 1H-NMR-based metabolomic study in pancreatic cancer cells

Gemcitabine is the first-line chemotherapy for pancreatic cancer. To overcome the often-acquired gemcitabine resistance, other drugs are used in combination with gemcitabine. It is well-known that cancer cells reprogram cellular metabolism, coupled with the up-regulation of selective nutrient transporters to feed into the altered metabolic pathways. Our previous studies have demonstrated that the amino acid transporter SLC6A14 is markedly up-regulated in pancreatic cancer and that it is a viable therapeutic target. α-Methyltryptophan (α-MT) is a blocker of SLC6A14 and is effective against pancreatic cancer in vitro and in vivo. In the present study, we tested the hypothesis that α-MT could synergize with gemcitabine in the treatment of pancreatic cancer. We investigated the effects of combination of α-MT and gemcitabine on proliferation, migration, and apoptosis in a human pancreatic cancer cell line, and examined the underlying mechanisms using 1H-NMR-based metabolomic analysis. These studies examined the intracellular metabolite profile and the extracellular metabolite profile separately. Combination of α-MT with gemcitabine elicited marked changes in a wide variety of metabolic pathways, particularly amino acid metabolism with notable alterations in pathways involving tryptophan, branched-chain amino acids, ketone bodies, and membrane phospholipids. The metabolomic profiles of untreated control cells and cells treated with gemcitabine or α-MT were distinctly separable, and the combination regimen showed a certain extent of overlap with the individual α-MT and gemcitabine groups. This represents the first study detailing the metabolomic basis of the anticancer efficacy of gemcitabine, α-MT and their combination.

Bitter melon juice intake with gemcitabine intervention circumvents resistance to gemcitabine in pancreatic patient-derived xenograft tumors

Chemoresistance to gemcitabine (GEM)-a frontline chemotherapeutic, resulting from its dysfunctional uptake and metabolism in cancer cells, is a major contributing factor for failed therapy in pancreatic cancer (PanC) patients. Therefore, there is an urgent need for agents that could reverse GEM resistance and allow continued chemosensitivity to the drug. We employed natural nontoxic agent (with anti-PanC potential) bitter melon juice (BMJ) and GEM to examine their combinatorial benefits against tumorigenesis of PanC patient-derived xenograft (PDX)-pancreatic ductal adenocarcinomas explants PDX272 (wild-type KRAS), PDX271 (mutant KRAS and SMAD4), and PDX266 (mutant KRAS). Anti-PanC efficacy of single agents vs combination in the three tumor explants, both at the end of active dosing regimen and following a drug-washout phase were compared. In animal studies, GEM alone treatment significantly inhibited PDX tumor growth, but effects were not sustained, as GEM-treated tumors exhibited regrowth posttreatment termination. However, combination-regimen displayed enhanced and sustained efficacy. Mechanistic assessments revealed that overcoming GEM resistance by coadministration with BMJ was possibly due to modulation of GEM transport/metabolism pathway molecules (ribonucleotide reductase regulatory subunit M1, human equilibrative nucleoside transporter 1, and deoxycytidine kinase). Study outcomes, highlighting significantly higher and sustained efficacy of GEM in combination with BMJ, make a compelling case for a clinical trial in PanC patients, wherein BMJ could be combined with GEM to target and overcome GEM resistance. In addition, given their specific effectiveness against KRAS-mutant tumors, this combination could be potentially beneficial to a broader PanC patient population.

Bitter Melon (Momordica Charantia), a Nutraceutical Approach for Cancer Prevention and Therapy

Cancer is the second leading cause of death worldwide. Many dietary plant products show promising anticancer effects. Bitter melon or bitter gourd (Momordica charantia) is a nutrient-rich medicinal plant cultivated in tropical and subtropical regions of many countries. Traditionally, bitter melon is used as a folk medicine and contains many bioactive components including triterpenoids, triterpene glycoside, phenolic acids, flavonoids, lectins, sterols and proteins that show potential anticancer activity without significant side effects. The preventive and therapeutic effects of crude extract or isolated components are studied in cell line-based models and animal models of multiple types of cancer. In the present review, we summarize recent progress in testing the cancer preventive and therapeutic activity of bitter melon with a focus on underlying molecular mechanisms. The crude extract and its components prevent many types of cancers by enhancing reactive oxygen species generation; inhibiting cancer cell cycle, cell signaling, cancer stem cells, glucose and lipid metabolism, invasion, metastasis, hypoxia, and angiogenesis; inducing apoptosis and autophagy cell death, and enhancing the immune defense. Thus, bitter melon may serve as a promising cancer preventive and therapeutic agent.

Inhibition of the key metabolic pathways, glycolysis and lipogenesis, of oral cancer by bitter melon extract

BACKGROUND

Metabolic reprogramming is one of the hallmarks of cancer which favours rapid energy production, biosynthetic capabilities and therapy resistance. In our previous study, we showed bitter melon extract (BME) prevents carcinogen induced mouse oral cancer. RNA sequence analysis from mouse tongue revealed a significant modulation in "Metabolic Process" by altering glycolysis and lipid metabolic pathways in BME fed group as compared to cancer group. In present study, we evaluated the effect of BME on glycolysis and lipid metabolism pathways in human oral cancer cells.

METHODS

Cal27 and JHU022 cells were treated with BME. RNA and protein expression were analysed for modulation of glycolytic and lipogenesis genes by quantitative real-time PCR, western blot analyses and immunofluorescence. Lactate and pyruvate level was determined by GC/MS. Extracellular acidification and glycolytic rate were measured using the Seahorse XF analyser. Shotgun lipidomics in Cal27 and JHU022 cell lines following BME treatment was performed by ESI/ MS. ROS was measured by FACS.

RESULTS

Treatment with BME on oral cancer cell lines significantly reduced mRNA and protein expression levels of key glycolytic genes SLC2A1 (GLUT-1), PFKP, LDHA, PKM and PDK3. Pyruvate and lactate levels and glycolysis rate were reduced in oral cancer cells following BME treatment. In lipogenesis pathway, we observed a significant reduction of genes involves in fatty acid biogenesis, ACLY, ACC1 and FASN, at the mRNA and protein levels following BME treatment. Further, BME treatment significantly reduced phosphatidylcholine, phosphatidylethanolamine, and plasmenylethanolamine, and reduced iPLA2 activity. Additionally, BME treatment inhibited lipid raft marker flotillin expression and altered its subcellular localization. ER-stress associated CHOP expression and generation of mitochondrial reactive oxygen species were induced by BME, which facilitated apoptosis.

CONCLUSION

Our study revealed that bitter melon extract inhibits glycolysis and lipid metabolism and induces ER and oxidative stress-mediated cell death in oral cancer. Thus, BME-mediated metabolic reprogramming of oral cancer cells will have important preventive and therapeutic implications along with conventional therapies.