Promise of bitter melon (Momordica charantia) bioactives in cancer prevention and therapy

Momordicine-I Suppresses Head and Neck Cancer Growth by Reprogrammimg Immunosuppressive Effect of the Tumor-Infiltrating Macrophages and B Lymphocytes

Head and neck cancer (HNC) is prevalent worldwide, and treatment options are limited. Momordicine-I (M-I), a natural component from bitter melon, shows antitumor activity against these cancers, but its mechanism of action, especially in the tumor microenvironment (TME), remains unclear. In this study, we establish that M-I reduces HNC tumor growth in two different immunocompetent mouse models using MOC2 and SCC VII cells. We demonstrate that the anticancer activity results from modulating several molecules in the monocyte/macrophage clusters in CD45+ populations in MOC2 tumors by single-cell RNA sequencing. Tumor-associated macrophages (TAM) often pose a barrier to antitumor effects, but following M-I treatment, we observe a significant reduction in the expression of Sfln4, a myeloid cell differentiation factor, and Cxcl3, a neutrophil chemoattractant, in the monocyte/macrophage populations. We further find that the macrophages must be in close contact with the tumor cells to inhibit Sfln4 and Cxcl3, suggesting that these TAMs are impacted by M-I treatment. Coculturing macrophages with tumor cells shows inhibition of Agr1 expression following M-I treatment, which is indicative of switching from M2 to M1 phenotype. Furthermore, the total B-cell population in M-I-treated tumors is significantly lower, whereas spleen cells also show similar results when cocultured with MOC2 cells. M-I treatment also inhibits PD1, PD-L1, and FoxP3 expression in tumors. Collectively, these results uncover the potential mechanism of M-I by modulating immune cells, and this new insight can help to develop M-I as a promising candidate to treat HNCs, either alone or as adjuvant therapy.

Exploring the mechanism of action bitter melon in the treatment of breast cancer by network pharmacology

BACKGROUND

Bitter melon has been used to stop the growth of breast cancer (BRCA) cells. However, the underlying mechanism is still unclear.

AIM

To predict the therapeutic effect of bitter melon against BRCA using network pharmacology and to explore the underlying pharmacological mechanisms.

METHODS

The active ingredients of bitter melon and the related protein targets were taken from the Indian Medicinal Plants, Phytochemistry and Therapeutics and SuperPred databases, respectively. The GeneCards database has been searched for BRCA-related targets. Through an intersection of the drug's targets and the disease's objectives, prospective bitter melon anti-BRCA targets were discovered. Gene ontology and kyoto encyclopedia of genes and genomes enrichment analyses were carried out to comprehend the biological roles of the target proteins. The binding relationship between bitter melon's active ingredients and the suggested target proteins was verified using molecular docking techniques.

RESULTS

Three key substances, momordicoside K, kaempferol, and quercetin, were identified as being important in mediating the putative anti-BRCA effects of bitter melon through the active ingredient-anti-BRCA target network study. Heat shock protein 90 AA, proto-oncogene tyrosine-protein kinase, and signal transducer and activator of transcription 3 were found to be the top three proteins in the protein-protein interaction network study. The several pathways implicated in the anti-BRCA strategy for an active component include phosphatidylinositol 3-kinase/protein kinase B signaling, transcriptional dysregulation, axon guidance, calcium signaling, focal adhesion, janus kinase-signal transducer and activator of transcription signaling, cyclic adenosine monophosphate signaling, mammalian target of rapamycin signaling, and phospholipase D signaling.

CONCLUSION

Overall, the integration of network pharmacology, molecular docking, and functional enrichment analyses shed light on potential mechanisms underlying bitter melon's ability to fight BRCA, implicating active ingredients and protein targets, as well as highlighting the major signaling pathways that may be altered by this natural product for therapeutic benefit.

Saponins from Momordica charantia exert hypoglycemic effect in diabetic mice by multiple pathways

The antidiabetic activity of saponins extracted from Momordica charantia (MCS) on streptozotocin-induced diabetic mice was investigated in order to elucidate the mechanism of MCS for exerting hypoglycemic effects. Saponins were first extracted from M. charantia L. and their composition was analyzed. The diabetic Kunming mice were fed low-dose saponins from M. charantia L. and high-dose MCS, using normal mice and diabetic mice as controls. Body weight, blood glucose level, oral glucose tolerance, serum C-peptide level, hepatic antioxidant capacity, hepatic glycogen and hexokinase in liver tissues, serum blood lipid level, and alpha-glucosidase activity in small intestines were measured, and microstructure of pancreatic islet was analyzed. The results showed that the total content of seven triterpenoid compounds in MCS was 18.24 μg/mg, with Momordicoside K having the highest content at 11.66 μg/mg. Diabetic mice treated with MCS at 100 and 200 mg/kg body weight daily for 30 days showed a maximum glucose reduction (p < .05) of 12.63% and 26.47%, respectively. MCS significantly decreased levels of postprandial hyperglycemia, serum lipid, α-glucosidase activity, and liver malondialdehyde. Additionally, levels of serum C-peptide and liver glycogen, as well as hexokinase and antioxidant enzyme activity, were significantly increased compared to the diabetic control groups. Histopathological results showed that MCS markedly reduced degenerative changes in islet β-cells. It is concluded that MCS exerts antidiabetic effects by improved hypoglycemic, hypolipidemic, and antioxidant effects, increased hexokinase activity and glycogen synthesis, and enhanced reparative effects on the histological architecture and insulin secretion function of the pancreas.

Bitter melon extract suppresses metastatic breast cancer cells (MCF-7 cells) growth possibly by hindering glucose uptake

Breast cancer is one of the most commonly diagnosed cancers among women, however the complete cure for metastatic breast cancer is lacking due to poor prognosis. There has been an increasing trend of dietary modifications including consumption of natural food for the prevention of cancer. One of the popular natural foods is bitter melon. Bitter melon grows in tropical and subtropical areas. Some of the beneficial effects of bitter melon towards disease including cancer have been reported at the whole body/organismal level. However, specific cellular mechanisms by which bitter melon exerts beneficial effects in breast cancer are lacking. In this study, we used a human metastatic breast cancer cell line, MCF-7 cell, to study if bitter melon alters glucose clearance from the culture medium. We co-cultured MCF-7 cells with bitter melon extract in the presence and absence of supplemented insulin and subsequently measured MCF-7 cells viability. In this study, we report a noble finding that bitter melon extract exerts cytotoxic effects on MCF-7 cells possibly via inhibition of glucose uptake. Our findings show that insulin rescues MCF-7 cells from the effects of bitter melon extract.

Momordicine I suppresses glioma growth by promoting apoptosis and impairing mitochondrial oxidative phosphorylation

Glioblastoma (GBM) is the most common type of primary brain tumor. Patients with GBM have poor survival outcomes. Isolated components of Momordica charantia have anticancer effects. However, the bioactivity of M. charantia extracts against GBM remains unknown. We tested four major extracts of M. charantia and found that momordicine I reduced glioma cell viability without serious cytotoxic effects on astrocytes. Momordicine I suppressed glioma cell colony formation, proliferation, migration, and invasion. Momordicine I also induced apoptosis, intracellular reactive oxygen species (ROS) production, and senescence in glioma cells. Moreover, momordicine I decreased the oxidative phosphorylation capacity of glioma cells and inhibited tumor sphere formation in temozolomide (TMZ)-resistant GBM cells. We further explored whether the antiglioma effect of momordicine I may be related to cell cycle modulation and DLGPA5 expression. Our results indicate that the cytotoxic effect of momordicine I on glioma cells suggests its potential therapeutic application to GBM treatment. See also Figure 1(Fig. 1).

The Role of Bitter Melon in Breast and Gynecological Cancer Prevention and Therapy

Phytotherapy has long represented a widely accepted treatment alternative to conventional therapy. Bitter melon is a vine with potent antitumor effects against numerous cancer entities. To date, no review article has, however, been published on the role of bitter melon in breast and gynecological cancer prevention and therapy. The current work constitutes the most comprehensive, up-to-date review of the literature, which highlights the promising anticancer effects of bitter melon on breast, ovarian, and cervical cancer cells and discusses future research recommendations.

Analysis of the Complete Mitochondrial Genome of the Bitter Gourd (Momordica charantia)

Bitter gourd (Momordica charantia L.) is a significant vegetable. Although it has a special bitter taste, it is still popular with the public. The industrialization of bitter gourd could be hampered by a lack of genetic resources. The bitter gourd's mitochondrial and chloroplast genomes have not been extensively studied. In the present study, the mitochondrial genome of bitter gourd was sequenced and assembled, and its substructure was investigated. The mitochondrial genome of bitter gourd is 331,440 bp with 24 unique core genes, 16 variable genes, 3 rRNAs, and 23 tRNAs. We identified 134 SSRs and 15 tandem repeats in the entire mitochondrial genome of bitter gourd. Moreover, 402 pairs of repeats with a length greater than or equal to 30 were observed in total. The longest palindromic repeat was 523 bp, and the longest forward repeat was 342 bp. We found 20 homologous DNA fragments in bitter gourd, and the summary insert length was 19,427 bp, accounting for 5.86% of the mitochondrial genome. We predicted a total of 447 potential RNA editing sites in 39 unique PCGs and also discovered that the ccmFN gene has been edited the most often, at 38 times. This study provides a basis for a better understanding and analysis of differences in the evolution and inheritance patterns of cucurbit mitochondrial genomes.

Green Synthesis of NiO Nanoflakes Using Bitter Gourd Peel, and Their Electrochemical Urea Sensing Application

To determine urea accurately in clinical samples, food samples, dairy products, and agricultural samples, a new analytical method is required, and non-enzymatic methods are preferred due to their low cost and ease of use. In this study, bitter gourd peel biomass waste is utilized to modify and structurally transform nickel oxide (NiO) nanostructures during the low-temperature aqueous chemical growth method. As a result of the high concentration of phytochemicals, the surface was highly sensitive to urea oxidation under alkaline conditions of 0.1 M NaOH. We investigated the structure and shape of NiO nanostructures using powder X-ray diffraction (XRD) and scanning electron microscopy (SEM). In spite of their flake-like morphology and excellent crystal quality, NiO nanostructures exhibited cubic phases. An investigation of the effects of bitter gourd juice demonstrated that a large volume of juice produced thin flakes measuring 100 to 200 nanometers in diameter. We are able to detect urea concentrations between 1-9 mM with a detection limit of 0.02 mM using our urea sensor. Additionally, the stability, reproducibility, repeatability, and selectivity of the sensor were examined. A variety of real samples, including milk, blood, urine, wheat flour, and curd, were used to test the non-enzymatic urea sensors. These real samples demonstrated the potential of the electrode device for measuring urea in a routine manner. It is noteworthy that bitter gourd contains phytochemicals that are capable of altering surfaces and activating catalytic reactions. In this way, new materials can be developed for a wide range of applications, including biomedicine, energy production, and environmental protection.

Immune System and Epidemics: The Role of African Indigenous Bioactive Substances

With over 6 million coronavirus pandemic deaths, the African continent reported the lowest death rate despite having a high disease burden. The African community's resilience to the pandemic has been attributed to climate and weather conditions, herd immunity, repeated exposure to infectious organisms that help stimulate the immune system, and a disproportionately large youth population. In addition, functional foods, herbal remedies, and dietary supplements contain micronutrients and bioactive compounds that can help boost the immune system. This review identified significant traditional fermented foods and herbal remedies available within the African continent with the potential to boost the immune system in epidemics and pandemics. Methodology: Databases, such as PubMed, the Web of Science, and Scopus, were searched using relevant search terms to identify traditional African fermented foods and medicinal plants with immune-boosting or antiviral capabilities. Cereal-based fermented foods, meat-, and fish-based fermented foods, and dairy-based fermented foods containing antioxidants, immunomodulatory effects, probiotics, vitamins, and peptides were identified and discussed. In addition, nine herbal remedies and spices belonging to eight plant families have antioxidant, immunomodulatory, anti-inflammatory, neuroprotective, hepatoprotective, cardioprotective, and antiviral properties. Peptides, flavonoids, alkaloids, sterols, ascorbic acid, minerals, vitamins, and saponins are some of the bioactive compounds in the remedies. Bioactive compounds in food and plants significantly support the immune system and help increase resistance against infectious diseases. The variety of food and medicinal plants found on the African continent could play an essential role in providing community resilience against infectious diseases during epidemics and pandemics. The African continent should investigate nutritional, herbal, and environmental factors that support healthy living and longevity.

Anti-leukemic principle(s) from Momordica charantia seeds induce differentiation of HL-60 cells through ERK/MAPK signalling pathway

Myeloid leukemia is one of the major causes of deaths among elderly with very poor prognosis. Due to the adverse effects of existing chemotherapeutic agents, plant-derived components are being screened for their anti-leukemic potential. Momordica charantia (bitter gourd) possesses a variety of therapeutic activities. We have earlier demonstrated anti-leukemic activity of acetone extract of M. charantia seeds. The present study reports purification of differentiation inducing principle(s) from further fractionated seed extract (hexane fraction of the acetone extract, Mc2-Ac-hex) using HL-60 cells. Out of the 5 peak fractions (P1-P5) obtained from normal phase HPLC of the Mc2-Ac-hex, only peak fraction 3 (P3) induced differentiation of HL-60 cells as evident from an increase in NBT-positive cells and increased expression of cell surface marker CD11b. The P3 differentiated the HL-60 cells to granulocytic lineage, established by increased CD15 (granulocytic cell surface marker) expression in the treated cells. Further, possible molecular mechanism and the signalling pathway involved in the differentiation of HL-60 cells were also investigated. Use of specific signalling pathway inhibitors in the differentiation study, and proteome array analysis of the treated cells collectively revealed the involvement the of ERK/MAPK mediated pathway. Partial characterization of the P3 by GC-MS analysis revealed the presence of dibutyl phthalate, and derivatives of 2,5-dihydrofuran to be the highest among the 5 identified compounds. This study thus demonstrated that purified differentiation-inducing principle(s) from M. charantia seed extract induce HL-60 cells to granulocytic lineage through ERK/MAPK signalling pathway.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10616-022-00547-x.

Development of a Fermented Bitter Gourd (Momordica charantia)–Grape Beverage Using Optimized Conditions

Bitter gourd beverages are well acclaimed for their health benefits, which have propelled their consumption. The beverages are prepared through a fermentation process, which is one of the oldest means of preserving and enhancing the flavour of many foods. Optimized conditions for the fermentation of a bitter gourd–grape beverage were investigated in our previous study. In the present study, a statistical comparison (one-way analysis of variance (ANOVA), Tukey’s honestly significant difference (HSD) test and an independent t-test)) of grape juice, bitter gourd juice and the fermented bitter gourd–grape beverage (with and without enzymes) was carried out to find significant differences among the products. Alcohol was found to be consistent for the four products with p > 0.05, whereas significant differences (p ≤ 0.05) in the pH, antioxidant activity (ferric reducing antioxidant assay (FRAP), 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2-azinobis (3-ethyl-benzothiazoline-6-sulfonic acid) (ABTS)), total titratable acidity (TTA), total soluble solids (TSS), total flavonoid content (TFC) and total phenolic content (TPC) were observed. The fermented bitter gourd–grape beverage (FBGGB) with enzymes had the highest antidiabetic potential content (27.07). The data obtained demonstrate that fermentation indeed enhances the biochemical function of vegetables (in this case, bitter gourd) and could thus be considered for the commercial processing of bitter gourd.

Recent advances in the development of bitter gourd seed oil: from chemical composition to potential applications

Non-conventional seed oils are being considered novelty foods due to the unique properties of their chemical constituents. Numerous such seed oils serve as nutritional and functional supplements, making them a point of interest for scholars. Bitter gourd (Momordica charantia L.) seed oil (BGSO) has been widely used in folk medicine worldwide for the treatment of different pathologies, such as diabetes, cancer, and several inflammatory diseases. Therefore, its nutritional and medicinal value has been extensively studied. Considering the potential use of BGSO, it is imperative to have a comprehensive understanding of this product to develop and use its biologically active ingredients in innovative food and pharmaceutical products. An extensive understanding of BGSO would also help improve the economic feasibility of the bitter gourd seed processing industry and help prevent environmental pollution associated with the raw waste produced during the processing of bitter gourd seeds. This review addresses the potential uses of BGSO in terms of food and pharmaceuticals industry perspectives and comprehensively summarizes the oil extraction process, chemical composition, biological activity, and the application prospects of BGSO in clinical medicine.

Transcriptome and metabolome changes induced by bitter melon (Momordica charantia)- intake in a high-fat diet induced obesity model

Background and aim

Metabolic syndrome (MetS) is a complex disease of physiological imbalances interrelated to abnormal metabolic conditions, such as abdominal obesity, type II diabetes, dyslipidemia and hypertension. In the present pilot study, we investigated the nutraceutical bitter melon (Momordica charantia L) -intake induced transcriptome and metabolome changes and the converging metabolic signaling networks underpinning its inhibitory effects against MetS-associated risk factors.

Experimental procedure

Metabolic effects of lyophilized bitter melon juice (BMJ) extract (oral gavage 200 mg/kg/body weight-daily for 40 days) intake were evaluated in diet-induced obese C57BL/6J male mice [fed-high fat diet (HFD), 60 kcal% fat]. Changes in a) serum levels of biochemical parameters, b) gene expression in the hepatic transcriptome (microarray analysis using Affymetrix Mouse Exon 1.0 ST arrays), and c) metabolite abundance levels in lipid-phase plasma [liquid chromatography mass spectrometry (LC-MS)-based metabolomics] after BMJ intervention were assessed.

Results and conclusion

BMJ-mediated changes showed a positive trend towards enhanced glucose homeostasis, vitamin D metabolism and suppression of glycerophospholipid metabolism. In the liver, nuclear peroxisome proliferator-activated receptor (PPAR) and circadian rhythm signaling, as well as bile acid biosynthesis and glycogen metabolism targets were modulated by BMJ (p < 0.05). Thus, our in-depth transcriptomics and metabolomics analysis suggests that BMJ-intake lowers susceptibility to the onset of high-fat diet associated MetS risk factors partly through modulation of PPAR signaling and its downstream targets in circadian rhythm processes to prevent excessive lipogenesis, maintain glucose homeostasis and modify immune responses signaling.

Electrospun PVA/CuONPs/Bitter Gourd Nanofibers with Improved Cytocompatibility and Antibacterial Properties: Application as Antibacterial Wound Dressing

Antibacterial and cyto-compatible tricomponent composite electrospun nanofibers comprised of polyvinyl alcohol (PVA), copper II oxide nanoparticles (CuONPs), and Momordica charantia (bitter gourd, MC) extract were examined for their potential application as an effective wound dressing. Metallic nanoparticles have a wide range of applications in biomedical engineering because of their excellent antibacterial properties; however, metallic NPs have some toxic effects as well. The green synthesis of nanoparticles is undergoing development with the goal of avoiding toxicity. The aim of adding Momordica charantia extract was to reduce the toxic effects of copper oxide nanoparticles as well as to impart antioxidant properties to electrospun nanofibers. Weight ratios of PVA and MC extract were kept constant while the concentration of copper oxide was optimized to obtain good antibacterial properties with reduced toxicity. Samples were characterized for their morphological properties, chemical interactions, crystalline structures, elemental analyses, antibacterial activity, cell adhesion, and toxicity. All samples were found to have uniform morphology without any bead formation, while an increase in diameters was observed as the CuO concentration was increased in nanofibers. All samples exhibited antibacterial properties; however, the sample with CuO concentration of 0.6% exhibited better antibacterial activity. It was also observed that nanofibrous mats exhibited excellent cytocompatibility with fibroblast (NIH3T3) cells. The mechanical properties of nanofibers were slightly improved due to the addition of nanoparticles. By considering the excellent results of nanofibrous mats, they can therefore be recommended for wound dressing applications.

Immunomodulatory effects and associated mechanisms of Momordica charantia and its phytochemicals

Momordica charantia L. (M. charantia), which is a member of the Cucurbitaceae family and widely distributed in tropical and subtropical regions, has been consumed as a vegetable and also used as herbal medicine for thousands of years worldwide.

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.

Visualizing Phytochemical-Protein Interaction Networks: Momordica charantia and Cancer

The in silico study of medicinal plants is a rapidly growing field. Techniques such as reverse screening and network pharmacology are used to study the complex cellular action of medicinal plants against disease. However, it is difficult to produce a meaningful visualization of phytochemical-protein interactions (PCPIs) in the cell. This study introduces a novel workflow combining various tools to visualize a PCPI network for a medicinal plant against a disease. The five steps are 1) phytochemical compilation, 2) reverse screening, 3) network building, 4) network visualization, and 5) evaluation. The output is a PCPI network that encodes multiple dimensions of information, including subcellular location, phytochemical class, pharmacokinetic data, and prediction probability. As a proof of concept, we built a PCPI network for bitter gourd (Momordica charantia L.) against colorectal cancer. The network and workflow are available at https://yumibriones.github.io/network/. The PCPI network highlights high-confidence interactions for further in vitro or in vivo study. The overall workflow is broadly transferable and can be used to visualize the action of other medicinal plants or small molecules against other diseases.

Bitter melon derived extracellular vesicles enhance the therapeutic effects and reduce the drug resistance of 5-fluorouracil on oral squamous cell carcinoma

Background

Plant-derived extracellular vesicles (PDEVs) have been exploited for cancer treatment with several benefits. Bitter melon is cultivated as a vegetable and folk medicine with anticancer and anti-inflammatory activities. 5-Fluorouracil (5-FU) is widely used for cancer treatment. However, 5-FU-mediated NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammation activation induced the resistance of oral squamous cell carcinoma (OSCC) cells to 5-FU. In this study, we explored the potential of bitter melon-derived extracellular vesicles (BMEVs) for enhancing the therapeutic efficacy and reduce the resistance of OSCC to 5-FU.

Results

Herein, we demonstrate that bitter melon derived extracellular vesicles (BMEVs), in addition to their antitumor activity against OSCC have intrinsic anti-inflammatory functions. BMEVs induced S phase cell cycle arrest and apoptosis. Apoptosis induction was dependent on reactive oxygen species (ROS) production and JUN protein upregulation, since pretreatment with N-acetyl cysteine or catechin hydrate could prevent apoptosis and JUN accumulation, respectively. Surprisingly, BMEVs significantly downregulated NLRP3 expression, although ROS plays a central role in NLRP3 activation. We further assessed the underlying molecular mechanism and proposed that the RNAs of BMEVs, at least in part, mediate anti-inflammatory bioactivity. In our previous studies, NLRP3 activation contributed to the resistance of OSCC cells to 5-FU. Our data clearly indicate that BMEVs could exert a remarkable synergistic therapeutic effect of 5-FU against OSCC both in vitro and in vivo. Most notably, NLRP3 downregulation reduced the resistance of OSCC to 5-FU.

Conclusions

Together, our findings demonstrate a novel approach to enhance the therapeutic efficacy and reduce the drug resistance of cancer cells to chemotherapeutic agents, which provides proof-of-concept evidence for the future development of PDEVs-enhanced therapy.

Graphic Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s12951-021-00995-1.

Thermal treatment enhances the α-glucosidase inhibitory activity of bitter melon (Momordica charantia) by increasing the free form of phenolic compounds and the contents of Maillard reaction products

Inhibition of α-glucosidase can slow carbohydrate metabolism, which is known as an effective strategy for diabetes treatment. The aim of this study is to evaluate the effect of thermal treatment (50, 60, and 70℃) for 15 days on the α-glucosidase inhibitory activity of bitter melon. The results show that the bitter melon heated at 70℃ for 12 days had the best α-glucosidase inhibitory effect. However, the amount of free polyphenols, 5-hydroxymethyl-2-furfural (5-HMF), and the browning degree of bitter melon generally increased with the time (15 days) and temperature of the thermal treatment, which is positively related to their antioxidant and α-glucosidase inhibitory activities. In conclusion, aged bitter melon shows great α-glucosidase inhibitory activity, which may be related to the increased free form of the involved phenolic compounds and Maillard reaction products. This suggests that thermal processing may be a good way to enhance the application of bitter melon for diabetes treatment. PRACTICAL APPLICATION: The thermal processing of bitter melon provides an application for diabetes treatment. This study demonstrated that heat-treated bitter melon can lower the blood glucose level; therefore, it can be used as a potential anti-hyperglycemic and functional food.

Three Selected Edible Crops of the Genus Momordica as Potential Sources of Phytochemicals: Biochemical, Nutritional, and Medicinal Values

Momordica species (Family Cucurbitaceae) are cultivated throughout the world for their edible fruits, leaves, shoots and seeds. Among the species of the genus Momordica, there are three selected species that are used as vegetable, and for medicinal purposes, Momordica charantia L (Bitter melon), Momordica foetida Schumach (Bitter cucumber) and Momordica balsamina L (African pumpkin). The fruits and leaves of these Momordica species are rich in primary and secondary metabolites such as proteins, fibers, minerals (calcium, iron, magnesium, zinc), β-carotene, foliate, ascorbic acid, among others. The extracts from Momordica species are used for the treatment of a variety of diseases and ailments in traditional medicine. Momordica species extracts are reputed to possess anti-diabetic, anti-microbial, anthelmintic bioactivity, abortifacient, anti-bacterial, anti-viral, and play chemo-preventive functions. In this review we summarize the biochemical, nutritional, and medicinal values of three Momordica species (M. charantia, M. foetida and M. balsamina) as promising and innovative sources of natural bioactive compounds for future pharmaceutical usage.

Momordicine-I, a Bitter Melon Bioactive Metabolite, Displays Anti-Tumor Activity in Head and Neck Cancer Involving c-Met and Downstream Signaling

Head and neck cancer (HNC) is one of the most aggressive cancers, and treatments are quite challenging due to the difficulty in early diagnosis, lack of effective chemotherapeutic drugs, adverse side effects and therapy resistance. We identified momordicine-I (M-I), a bioactive secondary metabolite in bitter melon (Momordica charantia), by performing liquid chromatography-high resolution electrospray ionization mass spectrometry (LC-HRESIMS) analysis. M-I inhibited human HNC cell (JHU022, JHU029, Cal27) viability in a dose-dependent manner without an apparent toxic effect on normal oral keratinocytes. Mechanistic studies showed that M-I inhibited c-Met and its downstream signaling molecules c-Myc, survivin, and cyclin D1 through the inactivation of STAT3 in HNC cells. We further observed that M-I was non-toxic and stable in mouse (male C57Bl/6) blood, and a favorable pharmacokinetics profile was observed after IP administration. M-I treatment reduced HNC xenograft tumor growth in nude mice and inhibited c-Met and downstream signaling. Thus, M-I has potential therapeutic implications against HNC.

Diverse roles of bitter melon (Momordica charantia) in prevention of oral cancer

Oral squamous cell carcinoma (OSCC) is one of the common lethal malignancies which is increasing rapidly in the world. Increasing risks from alcohol and tobacco habits, lack of early detection markers, lack of effective chemotherapeutic agents, recurrence and distant metastasis make the disease more complicated to manage. Laboratory-based studies and epidemiological studies indicate important roles of nutraceuticals to manage different cancers. The plant bitter melon (Momordica charantia) is a good source of nutrients and bio-active phytochemicals such as triterpenoids, triterpene glycosides, phenolic acids, flavonoids, lectins, sterols and proteins. The plant is widely grown in Asia, Africa, and South America. Bitter melon has traditionally been used as a folk medicine and Ayurvedic medicine in Asian culture to treat diseases such as diabetes, since ancient times. The crude extract and some of the isolated pure compounds of bitter melon show potential anticancer effects against different cancers. In this review, we shed light on its effect on OSCC. Bitter melon extract has been found to inhibit cell proliferation and metabolism, induce cell death and enhance the immune defense system in the prevention of OSCC in vitro and in vivo. Thus, bitter melon may be used as an attractive chemopreventive agent in progression towards OSCC clinical study.

The Effect of Bitter Melon (Momordica charantia) Extract on the Uptake of 99mTc Labeled Paclitaxel: In Vitro Monitoring in Breast Cancer Cells

Background:

Bitter Melon Extract (BME) is widely used for the treatment of various diseases worldwide due to its rich phytochemical and antioxidant content. The well-known anti-cancer drug Paclitaxel (PAC) plays a major role in the treatment of various cancer types such as ovarian, breast, and lung cancer. Technetium-99m (99mTc) radiolabeled paclitaxel is emerging as an imaging probe for breast cancer in vivo. 99mTc labeled compounds have been attracting more scientific attention since the achievement of earlier researches in Nuclear Medicine. People consume several types of diets of plant origin without knowing the interaction with radiolabeled compounds or radiopharmaceuticals.

Objectives:

In the current study, we aimed to monitor the potential effects of the BME on the uptake of 99mTc labeled Paclitaxel (99mTc-PAC) against MCF-7 (ER+) and MDA-MB-231 (ER-) cell lines by using in vitro methods.

Methods:

BME was obtained by the extraction of BM seeds by 80% ethanol. PAC was labeled with 99mTc by stannous chloride (SnCl2) as a reducing agent. Cytotoxicity and incorporation assays were performed on MCF-7 and MDA-MB-231 cells within the cell culture studies.

Results:

The uptake value of 99mTc-PAC on MCF-7 cells at 240 minutes was 6.20% and BME treated 99mTc- PAC value was 17.39%.

Conclusion:

It is observed that BME treatment has a significant effect on the uptake of 99mTc-PAC on MCF-7 cells which is a known estrogen receptor-positive breast carcinoma cell line. It is concluded that this effect could be due to the estrogen receptor-dependent interaction of BME.

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.

Plant triterpenoid saponins: biosynthesis, in vitro production, and pharmacological relevance

The saponins are a diverse class of natural products, with a broad scale distribution across different plant species. Chemically characterized as triterpenoid glycosides, they posses a 30C oxidosqualene precursor-based aglycone moiety (sapogenin), to which glycosyl residues are subsequently attached to yield the corresponding saponin. Based on the chemically distinct aglycone moieties, broadly, they are divided into triterpenoid saponins (dammaranes, ursanes, oleananes, lupanes, hopanes, etc.) and the sterol glycosides. This review aims to present in detail the biosynthesis patterns of the different aglycones from a common precursor and their glycosylation patterns to yield the functionally active glycoside. The review also presents recent advances in the pharmacological activities of these saponins, particularly as potent anti-neoplastic pharmacophores, antioxidants, or anti-viral/antibacterial agents. Since alternate production pedestals for these pharmacologically important triterpenes via cell and tissue cultures are an attractive option for their sustainable production, recent trends in the variety and scale of in vitro production of plant triterpenoids have also been discussed.

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

The established role of bitter melon juice (BMJ), a natural product, in activating master metabolic regulator adenosine monophosphate-activated protein kinase in pancreatic cancer (PanC) cells served as a basis for pursuing deeper investigation into the underlying metabolic alterations leading to BMJ efficacy in PanC. We investigated the comparative metabolic profiles of PanC cells with differential KRAS mutational status on BMJ exposure. Specifically, we employed nuclear magnetic resonance (NMR) metabolomics and in vivo imaging platforms to understand the relevance of altered metabolism in PanC management by BMJ. Multinuclear NMR metabolomics was performed, as a function of time, post-BMJ treatment followed by partial least square discriminant analysis assessments on the quantitative metabolic data sets to visualize the treatment group clustering; altered glucose uptake, lactate export and energy state were identified as the key components responsible for cell death induction. We next employed PANC1 xenograft model for assessing in vivo BMJ efficacy against PanC. Positron emission tomography ([18FDG]-PET) and magnetic resonance imaging on PANC1 tumor-bearing animals reiterated the in vitro results, with BMJ-associated significant changes in tumor volumes, tumor cellularity and glucose uptake. Additional studies in BMJ-treated PanC cells and xenografts displayed a strong decrease in the expression of glucose and lactate transporters GLUT1 and MCT4, respectively, supporting their role in metabolic changes by BMJ. Collectively, these results highlight BMJ-induced modification in PanC metabolomics phenotype and establish primarily lactate efflux and glucose metabolism, specifically GLUT1 and MCT4 transporters, as the potential metabolic targets underlying BMJ efficacy in PanC.

The Role of Momordica charantia in Resisting Obesity

Momordica charantia (M. charantia), commonly known as bitter gourd, bitter melon, kugua, balsam pear, or karela, is a tropical and sub-tropical vine belonging to the Cucurbitaceae family. It has been used to treat a variety of diseases in the traditional medicine of China, India, and Sri Lanka. Here, we review the anti-obesity effects of various bioactive components of M. charantia established at the cellular and organismal level. We aim to provide links between various bioactive components of M. charantia and their anti-obesity mechanism. An advanced search was conducted on the worldwide accepted scientific databases via electronic search (Google Scholar, Web of Science, ScienceDirect, ACS Publications, PubMed, Wiley Online Library, SciFinder, CNKI) database with the query TS = “Momordica charantia” and “obesity”. Information was also obtained from International Plant Names Index, Chinese Pharmacopoeia, Chinese herbal classic books, online databases, PhD and MSc dissertations, etc. First, studies showing the anti-obesity effects of M. charantia on the cells and on animals were classified. The major bioactive components that showed anti-obesity activities included proteins, triterpenoids, saponins, phenolics, and conjugated linolenic acids. Their mechanisms included inhibition of fat synthesis, promotion of glucose utilization, and stimulation of auxiliary lipid-lowering activity. Finally, we summarized the risks of excessive consumption of M. charantia and the application. Although further research is necessary to explore various issues, this review establishes the therapeutic potential of M. charantia and it is highly promising candidate for the development of anti-obesity health products and medicines.

Four new cucurbitane-type triterpenes from Momordica charantia L. with their cytotoxic activities and protective effects on H2O2-damaged pancreatic cells

Four new cucurbitane-type triterpenes were isolated from the fruit of Momordica charantia L. The structures of the new compounds were identified based on HR-ESI-MS and 1D- and 2D-NMR spectroscopic methods. The cytotoxicity of the isolated compounds was evaluated using three human cancer cell lines, HeLa, Caco2, and U87. Compound 3 exhibited significant cytotoxic activity against HeLa cells with an IC₅₀ value of 11.18 μM. Additionally, the cytoprotective activity of these compounds was determined in vitro against H₂O₂-induced pancreatic injury. The results revealed that all the compounds obtained possess cytoprotective effects against H₂O₂-induced injury in MIN6 β-cells at a concentration of 10 μM.

BG-4 from Bitter Gourd (Momordica charantia) Differentially Affects Inflammation In Vitro and In Vivo

BG-4 isolated from bitter gourd has been reported for anti-cancer properties. The objective was to evaluate the anti-inflammatory properties of BG-4 in vitro and in vivo. Comparative study of the anti-inflammatory properties of BG-4 in vitro and in vivo was conducted on lipopolysaccharide (LPS)-activated mouse macrophages, and on dextran sodium sulfate (DSS)-induced colitis in mice. BG-4 reduced the production of pro-inflammatory markers in LPS-activated macrophages. On the other hand, intraperitoneal administration of BG-4 in DSS-induced colitis led to colon shortening, elevated neutrophils infiltration and myeloperoxidase activity, presence of blood in the stool, and loss of body weight, with differential systemic and local effects on pro-inflammatory cytokines in vivo. The results demonstrated that BG-4 differentially affected inflammation in vitro and in vivo.

Momordicoside G Regulates Macrophage Phenotypes to Stimulate Efficient Repair of Lung Injury and Prevent Urethane-Induced Lung Carcinoma Lesions

Momordicoside G is a bioactive component from Momordica charantia, this study explores the contributions of macrophages to the effects of momordicoside G on lung injury and carcinoma lesion. In vitro, when administered at the dose that has no effect on cell viability in M2-like macrophages, momordicoside G decreased ROS and promoted autophagy and thus induced apoptosis in M1-like macrophages with the morphological changes. In the urethane-induced lung carcinogenic model, prior to lung carcinoma lesions, urethane induced obvious lung injury accompanied by the increased macrophage infiltration. The lung carcinoma lesions were positively correlated with lung tissue injury and macrophage infiltration in alveolar cavities in the control group, these macrophages showed mainly a M1-like (iNOS⁺/CD68⁺) phenotype. ELISA showed that the levels of IL-6 and IL-12 were increased and the levels of IL-10 and TGF-β1 were reduced in the control group. After momordicoside G treatment, lung tissue injury and carcinoma lesions were ameliorated with the decreased M1-like macrophages and the increased M2-like (arginase⁺/CD68⁺) macrophages, whereas macrophage depletion by liposome-encapsulated clodronate (LEC) decreased significantly lung tissue injury and carcinoma lesions and also attenuated the protective efficacy of momordicoside G. The M2 macrophage dependent efficacy of momordicoside G was confirmed in a LPS-induced lung injury model in which epithelial closure was promoted by the transfer of M2-like macrophages and delayed by the transfer of M1-like macrophages. To acquire further insight into the underlying molecular mechanisms by which momordicoside G regulates M1 macrophages, we conduct a comprehensive bioinformatics analysis of momordicoside G relevant targets and pathways involved in M1 macrophage phenotype. This study suggests a function of momordicoside G, whereby it selectively suppresses M1 macrophages to stimulate M2-associated lung injury repair and prevent inflammation-associated lung carcinoma lesions.

Are polyphenol antioxidants at the root of medicinal plant anti-cancer success?

ETHNOPHARMACOLOGICAL RELEVANCE

Given the severe side effects associated with most of the conventional cancer medications, as well as the expanding body of evidence indicating secondary toxicity of these drugs, individuals with cancer are increasingly turning to natural alternatives. Similarly, the pharmaceutical industry is in search of natural products to treat cancer. An understanding of the specific active components in plant products with which anti-cancer efficacy is achieved is required for this research to move forward.

AIM OF THE STUDY

To integrate data from cancer-relatestudies on plant-derived products or extracts, to elucidate whether these products may have similar active ingredients and/or mechanisms of action, that can explain their efficacy. This review also includes a discussion of the methodological complexities and important considerations involved in accurate isolation and characterisation of active substances from plant material.

CONCLUSIONS

From the literature reviewed, most plant products with consistently reported anti-cancer efficacy contains high levels of polyphenols or other potent antioxidants and their mechanisms of action correlate to that reported for isolated antioxidants in the context of cancer. This suggests that natural products may indeed become the panacea against this chronic disease - either as therapeutic medicine strategy or to serve as templates for the design of novel synthetic drugs. The recommendation is made that antioxidant activity of plant actives and especially polyphenols, should be the focus of anti-cancer drug discovery initiatives. Lastly, researchers are advised to exploit current techniques of chemical compound characterisation when investigating polyphenol-rich plants to enable the easy consolidation of research findings from different laboratories.

Cucurbitane triterpenoids from the fruit of Momordica charantia L. and their anti-hepatic fibrosis and anti-hepatoma activities

Momordica charantia L. (Cucurbitaceae) is a popular vegetable and traditional folk medicine, that has been used for hundreds of years. In this study, three undescribed cucurbitane-type triterpene glycosides furpyronecucurbitane A, goyaglycoside I and charantagenin F along with nine known compounds were isolated from the immature fruit of Momordica charantia L. Their structures were identified on the basis of extensive 1D, 2D NMR and HRESIMS spectroscopy analysis. All isolated compounds were examined for their anti-hepatic fibrosis activity against murine hepatic stellate cells (t-HSC/Cl-6) and anti-hepatoma activity against two kinds of liver cancer cell lines (HepG2 and Hep3B). Among them, karaviloside III exhibited excellent inhibitory activity against activated t-HSC/Cl-6 cells and cytotoxic activity against Hep3B and HepG2 cell lines with IC₅₀ values of 3.74 ± 0.13, 16.68 ± 2.07 and 4.12 ± 0.36 μM, respectively, which may potential to be developed as a chemotherapy agent for treatment hepatic fibrosis or carcinoma and protection against both diseases.

Effectiveness of bitter melon extract in the treatment of ischemic wounds in rats

There is no consensus on the properties of an ideal dressing for treating wounds. The aim of this study was to investigate the efficacy of dressings using topically administered bitter melon extract with olive oil, pure olive oil, nitrofurazone, and saline in the healing of ischemic wounds. A sample group of 48 rats was used in the trial. Their wounds were treated with bitter melon extract, pure olive oil, nitrofurazone, and saline. Data were collected between October 2014 and April 2015. The highest percentage (94.7%) of wound healing was observed in the bitter melon extract group and the lowest percentage (86.3%) in the nitrofurazone group. At the end of the 21st day, macroscopic reepithelialization was observed in 9 wounds in the bitter melon extract group (75%), in 6 wounds in the pure olive oil group (50%), and in only 3 wounds in the nitrofurazone and saline groups (25%). It can be concluded that dressing with a bitter melon extract is more efficient in the treatment of wounds than using nitrofurazone or saline, and that dressing with olive oil accelerates wound healing, although not as much as dressing with bitter melon extract.

Disrupting cholesterol esterification by bitter melon suppresses triple-negative breast cancer cell growth

Triple negative breast cancer (TNBC) is aggressive with a worse prognosis. We have recently shown that bitter melon extract (BME) treatment was more effective in inhibition of TNBC tumor growth in mouse models as compared to ER positive breast tumor growth. Aberrant dysregulation of lipid metabolism is associated with breast cancer progression, however, anti-cancer mechanism of BME linking lipid metabolism in breast cancer growth remains unexplored. Here, we observed that accumulation of esterified cholesterol was reduced in BME treated TNBC cell lines as compared to control cells. We next evaluated expression levels of acyl-CoA: cholesterol acyltransferase 1 (ACAT-1) in TNBC cells treated with BME. Our results demonstrated that BME treatment inhibited ACAT-1 expression in TNBC cells. Subsequently, we found that sterol regulatory element-binding proteins-1 and -2, and FASN was significantly reduced in BME treated TNBC cell lines. Low-density lipoprotein receptor was also downregulated in BME treated TNBC cells as compared to control cells. We further demonstrated that BME feeding reduced tumor growth in TNBC mammospheres implanted into NSG mice, and inhibits ACAT-1 expression. To our knowledge, this is the first report demonstrating BME suppresses TNBC cell growth through ACAT-1 inhibition, and have potential for additional therapeutic regimen against human breast cancer.

Bitter melon juice exerts its efficacy against pancreatic cancer via targeting both bulk and cancer stem cells

Pancreatic cancer (PanC) is one of the deadliest malignancies worldwide and frontline treatment with gemcitabine becomes eventually ineffective due to increasing PanC resistance, suggesting additional approaches are needed to manage PanC. Recently, we have shown the efficacy of bitter melon juice (BMJ) against PanC cells, including those resistant to gemcitabine. As cancer stem cells (CSCs) are actively involved in PanC initiation, progression, relapse and drug-resistance, here we assessed BMJ ability in targeting pancreatic cancer-associated cancer stem cells (PanC-CSCs). We found BMJ efficacy against CD44+ /CD24+ /EpCAMhigh enriched PanC-CSCs in spheroid assays; BMJ also increased the sensitivity of gemcitabine-resistant PanC-CSCs. Exogenous addition of BMJ to PanC-CSC generated spheroids (not pre-exposed to BMJ) also significantly reduced spheroid number and size. Mechanistically, BMJ effects were associated with a decrease in the expression of genes and proteins involved in PanC-CSC renewal and proliferation. Specifically, immunofluorescence staining showed that BMJ decreases protein expression/nuclear localization of CSC-associated transcription factors SOX2, OCT4 and NANOG, and CSC marker CD44. Immunohistochemical analysis of MiaPaCa2 xenografts from BMJ treated animals also showed a significant decrease in the levels of CSC-associated transcription factors. Together, these results show BMJ potential in targeting PanC-CSC pool and associated regulatory pathways, suggesting the need for further investigation of its efficacy against PanC growth and progression including gemcitabine-resistant PanC.

Bitter gourd (Momordica charantia) as a rich source of bioactive components to combat cancer naturally: Are we on the right track to fully unlock its potential as inhibitor of deregulated signaling pathways

Research over decades has progressively explored pharmacological actions of bitter gourd (Momordica charantia). Biologically and pharmacologically active molecules isolated from M. charantia have shown significant anti-cancer activity in cancer cell lines and xenografted mice. In this review spotlight was set on the bioactive compounds isolated from M. charantia that effectively inhibited cancer development and progression via regulation of protein network in cancer cells. We summarize most recent high-quality research work in cancer cell lines and xenografted mice related to tumor suppressive role-play of M. charantia and its bioactive compounds. Although M. charantia mediated health promoting, anti-diabetic, hepatoprotective, anti-inflammatory effects have been extensively investigated, there is insufficient information related to regulation of signaling networks by bioactive molecules obtained from M. charantia in different cancers. M. charantia has been shown to modulate AKT/mTOR/p70S6K signaling, p38MAPK-MAPKAPK-2/HSP-27 pathway, cell cycle regulatory proteins and apoptosis-associated proteins in different cancers. However, still there are visible knowledge gaps related to the drug targets in different cancers because we have not yet developed comprehensive understanding of the M. charantia mediated regulation of signal transduction pathways. To explore these questions, experimental platforms are needed that can prove to be helpful in getting a step closer to personalized medicine.

Immunomodulatory Effects of Momordica charantia Extract in the Prevention of Oral Cancer

In recent times, bitter melon extract (BME) has gained significant attention for its anticancer efficacy against various malignancies. In this issue, Sur and colleagues show that BME prevents the development of 4-nitronitroquinoline 1-oxide-induced oral dysplasia and squamous cell carcinoma (SCC) in an immunocompetent mouse model. Importantly, gene ontology and pathway analyses revealed an elevated expression of s100a9, IL23a, IL1β, and PDCD1/PD1 of immune system during oral cancer development, which was significantly suppressed by BME. Overall, this study demonstrates the potential clinical benefits of BME in preventing and delaying the progression of oral dysplasia to SCC. Cancer Prev Res; 11(4); 185-6. ©2018 AACRSee related article by Sur et al., p. 191.

MAP30 promotes apoptosis of U251 and U87 cells by suppressing the LGR5 and Wnt/β-catenin signaling pathway, and enhancing Smac expression

Significant antitumor activity of Momordica anti-human immunodeficiency virus protein of 30 kDa (MAP30) purified from Momordica charantia has been the subject of previous research. However, the effective mechanism of MAP30 on malignant glioma cells has not yet been clarified. The aim of the present study was to investigate the effects and mechanism of MAP30 on U87 and U251 cell lines. A Cell Counting Kit-8 assay, wound healing assay and Transwell assay were used to detect the effects on U87 and U251 cells treated with different concentrations of MAP30 (0.5, 1, 2, 4, 8 and 16 µM) over different periods of time. Proliferation, migration and invasion of each cell line were markedly inhibited by MAP30 in a dose- and time-dependent manner. Flow cytometry and fluorescence staining demonstrated that apoptosis increased and the cell cycle was arrested in S-phase in the two investigated cell lines following MAP30 treatment. Western blot analysis demonstrated that leucine-rich-repeat-containing G-protein-coupled receptor 5 (LGR5) expression and key proteins in the Wnt/β-catenin signaling pathway were apparently decreased, whereas second mitochondria-derived activator of caspase (Smac) protein expression significantly increased with MAP30 treatment in the same manner. These results suggest that MAP30 markedly induces apoptosis in U87 and U251 cell lines by suppressing LGR5 and the Wnt/β-catenin signaling pathway, and enhancing Smac expression in a dose- and time-dependent manner.

Bitter Melon Enhances Natural Killer-Mediated Toxicity against Head and Neck Cancer Cells

Natural killer (NK) cells are one of the major components of innate immunity, with the ability to mediate antitumor activity. Understanding the role of NK-cell-mediated tumor killing in controlling of solid tumor growth is still in the developmental stage. We have shown recently that bitter melon extract (BME) modulates the regulatory T cell (Treg) population in head and neck squamous cell carcinoma (HNSCC). However, the role of BME in NK-cell modulation against HNSCC remains unknown. In this study, we investigated whether BME can enhance the NK-cell killing activity against HNSCC cells. Our results indicated that treatment of human NK-cell line (NK3.3) with BME enhances ability to kill HNSCC cells. BME increases granzyme B accumulation and translocation/accumulation of CD107a/LAMP1 in NK3.3 cells exposed to BME. Furthermore, an increase in cell surface expression of CD16 and NKp30 in BME-treated NK3.3 cells was observed when cocultured with HNSCC cells. Collectively, our results demonstrated for the first time that BME augments NK-cell-mediated HNSCC killing activity, implicating an immunomodulatory role of BME. Cancer Prev Res; 10(6); 337-44. ©2017 AACR.