Chrysin, Abundant in Morinda citrifolia Fruit Water-EtOAc Extracts, Combined with Apigenin Synergistically Induced Apoptosis and Inhibited Migration in Human Breast and Liver Cancer Cells

The Many Facets of PPAR-γ Agonism in Obesity and Associated Comorbidities: Benefits, Risks, Challenges, and Future Directions

PURPOSE OF REVIEW

Obesity is strongly associated with cardiometabolic disorders and certain malignancies, emphasizing the key role of adipose tissue in human health. While incretin mimetics have shown effectiveness in glycemic control and weight loss, a holistic strategy for combating obesity and associated comorbidities remains elusive. This review explores peroxisome proliferator-activated receptor gamma (PPAR-γ) agonism as a potential therapeutic approach, highlighting its benefits, addressing its limitations, and outlining future directions for developing more effective treatment strategies.

RECENT FINDINGS

Both natural and synthetic PPAR-γ agonists hold significant therapeutic potential as insulin sensitizers, while also demonstrating anti-inflammatory properties and playing a critical role in regulating lipid metabolism. However, the clinical use of natural agonists is limited by poor bioavailability, while synthetic agents like thiazolidinediones are associated with adverse effects, including fluid retention, weight gain, and bone loss. Current research is focused on developing modified, tissue-specific PPAR-γ agonists, as well as dual PPAR-α/PPAR-γ agonists, with improved safety profiles to mitigate these side effects. Nanotechnology-based drug delivery systems also hold promise for enhancing bioavailability and therapeutic efficacy. Furthermore, the transformative potential of machine learning and artificial intelligence offers opportunities to accelerate advancements in this field. PPAR-γ agonists exhibit significant potential in addressing metabolic syndrome, cardiovascular disease, and cancer. However, their clinical use is restricted by safety concerns and suboptimal pharmacokinetics. Innovations in modified PPAR-γ agonists, nanotechnology-based delivery systems, and computational tools hold promise for creating safer and more effective therapeutic options for obesity and its associated disorders.

Pharmacodynamics and safety in relation to dose and response of plant flavonoids in treatment of cancers

Despite the recent advancements in developing bioactive nutraceuticals as anticancer modalities, their pharmacodynamics, safety profiles, and tolerability remain elusive, limiting their success in clinical trials. The failure of anticancer drugs in clinical trials can be attributed to the changes in drug clearance, absorption, and cellular responses, which alter the dose-response efficacy, causing adverse health effects. Flavonoids demonstrate a biphasic dose-response phenomenon exerting a stimulatory or inhibitory effect and often follow a U-shaped curve in different preclinical cancer models. A double-edged sword, bioflavonoids' antioxidant or prooxidant properties contribute to their hormetic behavior and facilitate redox homeostasis by regulating the levels of reactive oxygen species (ROS) in cells. Emerging reports suggest a need to discuss the pharmacodynamic broad-spectrum of plant flavonoids to improve their therapeutic efficacy, primarily to determine the ideal dose for treating cancer. This review discusses the dose-response effects of a few common plant flavonoids against some types of cancers and assesses their safety and tolerability when administered to patients. Moreover, we have emphasized the role of dietary-rich plant flavonoids as nutraceuticals in cancer treatment and prevention.

Apigenin as an emerging hepatoprotective agent: current status and future perspectives

Apigenin (C15H10O5, API) is a natural flavonoid widely found in vegetables, fruits, and plants such as celery, oranges, and chamomile. In recent years, API has attracted considerable attention as a dietary supplement due to its low toxicity, non-mutagenic properties and remarkable therapeutic efficacy in various diseases. In particular, evidence from a large number of preclinical studies suggests that API has promising effects in the prevention and treatment of a variety of liver diseases, including multifactorial liver injury, non-alcoholic fatty liver disease/non-alcoholic steatohepatitis, liver fibrosis and liver cancer. This paper provides a comprehensive review of the progress of research into the therapeutic applications of API in liver diseases as of August 2024, based on literature retrieved from databases such as Web of Science, PubMed, CNKI, Google Scholar and ScienceDirect. The hepatoprotective effects of API involve multiple molecular mechanisms, including inhibition of inflammation, alleviation of hepatic oxidative stress, amelioration of insulin resistance, promotion of fatty acid oxidation, inhibition of liver cancer cell proliferation and differentiation, and induction of tumour cell apoptosis. More importantly, signaling pathways such as Nrf2, NF-κB, PI3K/Akt/mTOR, NLRP3, Wnt/β-catenin, TGF-β1/Smad3, AMPK/SREBP, PPARα/γ, MAPKs, and Caspases are identified as key targets through which API exerts its beneficial effects in various liver diseases. Studies on its toxicity and pharmacokinetics indicate that API has low toxicity, is slowly metabolized and excreted in vivo, and has low oral bioavailability. In addition, the paper summarises and discusses the sources, physicochemical properties, new dosage forms, and current challenges and opportunities of API, with the aim of providing direction and rationale for the further development and clinical application of API in the food, pharmaceutical and nutraceutical fields.

Metabolomics Reveals Glycerophospholipids, Peptides, and Flavonoids Contributing to Breast Meat Flavor and Benefit Properties of Beijing-You Chicken

Unique metabolites contribute to the performance of meat flavor and potential function. In this study, UHPLC-Q Exactive HF-X-based metabolomics and multivariate analysis were applied to explore the characteristic metabolites in the breast meat of Beijing-You chicken (BYC) aged 150, 300, and 450 days (D150, D300, and D450). Based on the criteria of variable importance in the projection (VIP) > 1 and p < 0.05, a total of 154 and 97 differential metabolites (DMs) were screened out compared with D450 (D450 vs. D150, D450 vs. D300), respectively. In general, the relative content of carnosine, L-L-homoglutathione, demethyloleuropein, neohesperidin dihydrochalcone, 7-chloro-2-(3,4-dimethoxyphenyl)-3,5-dihydroxy-6,8-dimethoxy-4H-chromen-4-one, glycerophospholipids, exhibited the highest abundance at D450, while balenine, anserine, L-beta-aspartyl-L-leucine, glutathione, oxidized glutathione, stearoylcarnitine, ganoderic acid alpha, oleuroside, Lysoglycerophospholipid species (LGP) presented a downward trend with age. These 210 DMs were involved in 10 significantly enriched pathways related to the synthesis and metabolism of amino acids, peptides, and glycerophospholipid, such as glutathione metabolism, histidine metabolism, glycerophospholipid metabolism, arginine biosynthesis, tyrosine metabolism, and lysine degradation. In conclusion, this work could not only facilitate a better understanding of the differences of chicken flavor and benefit properties with age, but also provide potential valuable bioactive compounds for further research.

Comparative Analysis of Acetylated Flavonoids' Chemopreventive Effects in Different Cancer Cell Lines

Flavonoids, a class of natural compounds with anticancer activity, exhibit varying biological activities and potencies based on their structural differences. Acylation, including acetylation of flavonoids, generally increases their structural diversity, which is closely related to the diversity of bioactivity within this group of compounds. However, it remains largely unknown how acetylation affects the bioactivity of many flavonoids. Based on our previous findings that O-acetylation enhances quercetin's bioactivity against various cancer cells, we synthesized 12 acetylated flavonoids, including seven novel compounds, to investigate their anticancer activities in the MDA-MB-231, HCT-116, and HepG2 cell lines. Our results showed that acetylation notably enhanced the cell proliferation inhibitory effect of quercetin and kaempferol across all cancer cell lines tested. Interestingly, while the 5,7,4'-O-triacetate apigenin (3Ac-A) did not show an enhanced the effect of inhibition of cell proliferation through acetylation, it exhibited significantly strong anti-migration activity in MDA-MB-231 cells. In contrast, the 7,4'-O-diacetate apigenin (2Ac-Q), which lacks acetylation at the 5-position hydroxy group, showed enhanced cell proliferation inhibitory effect but had weaker anti-migration effects compared to 3Ac-A. These results indicated that acetylated flavonoids, especially quercetin, kaempferol, and apigenin derivatives, are promising for anticancer applications, with 3Ac-A potentially having unique anti-migration pathways independent of apoptosis induction. This study highlights the potential application of flavonoids in novel chemopreventive strategies for their anti-cancer activity.

Advances in nanocarrier-mediated delivery of chrysin: Enhancing solubility, bioavailability, and anticancer efficacy

Chrysin, a natural phytochemical compound found in various plant sources, possesses diverse pharmacological benefits, including anticancer, antioxidant, antidiabetic, neuroprotective, cardioprotective, hepatoprotective, immunoregulatory, and anti-inflammatory properties. Despite its well-documented biological activities, chrysin's low water solubility and bioavailability hinder its clinical development. This review explores the application of nanocarriers as a strategic approach to overcome these challenges and enhance the delivery of chrysin. Nanocarriers, including polymer-based nanoparticles (NPs), lipid-based NPs, and inorganic nanocarriers, have shown promise in improving the solubility, bioavailability, and tumor-targeted delivery of chrysin. The paper discusses chrysin's anticancer effects on different types of human cancers, elucidating its impact on crucial signaling pathways involved in tumorigenesis. The review categorizes and analyzes various nanocarriers, providing insights into their structural properties and drug release profiles. Among the nanocarriers, polymer-based NPs, especially those utilizing PLGA, emerge as promising strategies for chrysin encapsulation, demonstrating improvements in drug release, stability, and bioavailability. Lipid-based NPs and inorganic nanocarriers also exhibit potential in enhancing chrysin delivery. The comprehensive insights provided contribute to a deeper understanding of chrysin's pharmacological properties and its potential clinical applications, offering valuable perspectives for future research and translation into clinical settings. The review underscores the importance of selecting suitable structures for chrysin encapsulation to enhance its physicochemical properties and anticancer effects, paving the way for innovative nanomedicine approaches in cancer therapy.

Michael Acceptors as Anti-Cancer Compounds: Coincidence or Causality?

Michael acceptors represent a class of compounds with potential anti-cancer properties. They act by binding to nucleophilic sites in biological molecules, thereby disrupting cancer cell function and inducing cell death. This mode of action, as well as their ability to be modified and targeted, makes them a promising avenue for advancing cancer therapy. We are investigating the molecular mechanisms underlying Michael acceptors and their interactions with cancer cells, in particular their ability to interfere with cellular processes and induce apoptosis. The anti-cancer properties of Michael acceptors are not accidental but are due to their chemical structure and reactivity. The electrophilic nature of these compounds allows them to selectively target nucleophilic residues on disease-associated proteins, resulting in significant therapeutic benefits and minimal toxicity in various diseases. This opens up new perspectives for the development of more effective and precise cancer drugs. Nevertheless, further studies are essential to fully understand the impact of our discoveries and translate them into clinical practice.

Leveraging a Y. lipolytica naringenin chassis for biosynthesis of apigenin and associated glucoside

Flavonoids are a diverse set of natural products with promising bioactivities including anti-inflammatory, anti-cancer, and neuroprotective properties. Previously, the oleaginous host Yarrowia lipolytica has been engineered to produce high titers of the base flavonoid naringenin. Here, we leverage this host along with a set of E. coli bioconversion strains to produce the flavone apigenin and its glycosylated derivative isovitexin, two potential nutraceutical and pharmaceutical candidates. Through downstream strain selection, co-culture optimization, media composition, and mutant isolation, we were able to produce168 mg/L of apigenin, representing a 46% conversion rate of 2-(R/S)-naringenin to apigenin. This apigenin platform was modularly extended to produce isovitexin by addition of a second bioconversion strain. Together, these results demonstrate the promise of microbial production and modular bioconversion to access diversified flavonoids.

Anticancer and chemopreventive potential of Morinda citrifolia L. bioactive compounds: A comprehensive update

Morinda citrifolia L., commonly known as Noni, has a longstanding history in traditional medicine for treating various diseases. Recently, there has been an increased focus on exploring Noni extracts and phytoconstituents, particularly for their effectiveness against cancers such as lung, esophageal, liver, and breast cancer, and their potential in cancer chemoprevention. This study aims to provide a comprehensive review of in vitro and in vivo studies assessing Noni's impact on cancer, alongside an exploration of its bioactive compounds. A systematic review was conducted, encompassing a wide range of scientific databases to gather pertinent literature. This review focused on in vitro and in vivo studies, as well as clinical trials that explore the effects of Noni fruit and its phytoconstituents-including anthraquinones, flavonoids, sugar derivatives, and neolignans-on cancer. The search was meticulously structured around specific keywords and criteria to ensure a thorough analysis. The compiled studies highlight Noni's multifaceted role in cancer therapy, showcasing its various bioactive components and their modes of action. This includes mechanisms such as apoptosis induction, cell cycle arrest, antiangiogenesis, and immune system modulation, demonstrating significant anticancer and chemopreventive potential. The findings reinforce Noni's potential as a safe and effective option in cancer prevention and treatment. This review underscores the need for further research into Noni's anticancer properties, with the hope of stimulating additional studies and clinical trials to validate and expand upon these promising findings.

Integrated network pharmacology and cellular assay reveal the biological mechanisms of Limonium sinense (Girard) Kuntze against Breast cancer

BACKGROUND

Limonium Sinense (Girard) Kuntze (L. sinense) has been widely used for the treatment of anaemia, bleeding, cancer, and other disorders in Chinese folk medicine. The aim of this study is to predict the therapeutic effects of L. sinense and investigate the potential mechanisms using integrated network pharmacology methods and in vitro cellular experiments.

METHODS

The active ingredients of L. sinense were collected from published literature, and the potential targets related to L. sinense were obtained from public databases. Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) and DisGeNET enrichment analyses were performed to explore the underlying mechanisms. Molecular docking, cellular experiments, RNA-sequencing (RNA-seq) and Gene Expression Omnibus (GEO) datasets were employed to further evaluate the findings.

RESULTS

A total of 15 active ingredients of L. sinense and their corresponding 389 targets were obtained. KEGG enrichment analysis revealed that the biological effects of L. sinense were primarily associated with "Pathways in cancer". DisGeNET enrichment analysis highlighted the potential role of L. sinense in the treatment of breast cancer. Apigenin within L. sinense showed promising potential against cancer. Cellular experiments demonstrated that the L. sinense ethanol extract (LSE) exhibited a significant growth inhibitory effect on multiple breast cancer cell lines in both 2D and 3D cultures. RNA-seq analysis revealed a potential impact of LSE on breast cancer. Additionally, analysis of GEO datasets verified the significant enrichment of breast cancer and several cancer-related pathways upon treatment with Apigenin in human breast cancer cells.

CONCLUSION

This study predicts the biological activities of L. sinense and demonstrates the inhibitory effect of LSE on breast cancer cells, highlighting the potential application of L. sinense in cancer treatment.

Phytobioactive compounds as therapeutic agents for human diseases: A review

Phytobioactive compounds are plant secondary metabolites and bioactive compounds abundantly present in medicinal plants and have remarkable therapeutic potential. Oxidative stress and antibiotic resistance are major causes of present-day ailments such as diabetes, atherosclerosis, cardiovascular disorders, cancer, and inflammation. The data for this review were collected from Google Scholar, PubMed, Directory of Open Access Journals (DOAJ), and Science Direct by using keywords: "Medicinal plants, Phytobioactive compounds, Polyphenols, Alkaloids, Carotenoids etc." Several studies have reported the pharmacological and therapeutic potential of the phytobioactives. Polyphenols, alkaloids, terpenes, and polysaccharides isolated from medicinal plants showed remarkable antioxidant, anticancer, cytotoxic, anti-inflammatory, cardioprotective, hepatoprotective, immunomodulatory, neuroprotective, and antidiabetic activities. This literature review was planned to provide comprehensive insight into the biopharmacological and therapeutic potential of phytobioactive compounds. The techniques used for the extraction and isolation of phytobioactive compounds, and bioassays required for their biological activities such as antioxidant, antimicrobial, anti-inflammatory, and cytotoxic activities, have been discussed. Characterization techniques for the structural elucidation of phytobioactive compounds such as HPLC, TLC, FTIR, GC-MS/MS, and NMR have also been discussed. This review concludes that phytobioactive compounds may be used as potential alternative to synthetic compounds as therapeutic agents for the treatment of various diseases.

Anticancer Potential of Apigenin and Isovitexin with Focus on Oncogenic Metabolism in Cancer Stem Cells

It has been demonstrated that cancer stem cells (CSCs) go through metabolic changes that differentiate them from non-CSCs. The altered metabolism of CSCs plays a vital role in tumor initiation, progression, immunosuppression, and resistance to conventional therapy. Therefore, defining the role of CSC metabolism in carcinogenesis has emerged as a main focus in cancer research. Two natural flavonoids, apigenin and isovitexin, have been shown to act synergistically with conventional chemotherapeutic drugs by sensitizing CSCs, ultimately leading to improved therapeutic efficacy. The aim of this study is to present a critical and broad evaluation of the anti-CSC capability of apigenin and isovitexin in different cancers as novel and untapped natural compounds for developing drugs. A thorough review of the included literature supports a strong association between anti-CSC activity and treatment with apigenin or isovitexin. Additionally, it has been shown that apigenin or isovitexin affected CSC metabolism and reduced CSCs through various mechanisms, including the suppression of the Wnt/β-catenin signaling pathway, the inhibition of nuclear factor-κB protein expression, and the downregulation of the cell cycle via upregulation of p21 and cyclin-dependent kinases. The findings of this study demonstrate that apigenin and isovitexin are potent candidates for treating cancer due to their antagonistic effects on CSC metabolism.

Quercetin Induces Apoptosis in HepG2 Cells via Directly Interacting with YY1 to Disrupt YY1-p53 Interaction

Quercetin is a flavonol found in edible plants and possesses a significant anticancer activity. This study explored the mechanism by which quercetin prevented liver cancer via inducing apoptosis in HepG2 cells. Quercetin induced cell proliferation and apoptosis through inhibiting YY1 and facilitating p53 expression and subsequently increasing the Bax/Bcl-2 ratio. The results revealed that YY1 knockdown promoted apoptosis, whilst YY1 overexpression suppressed apoptosis via direct physical interaction between YY1 and p53 to regulate the p53 signaling pathway. Molecular docking using native and mutant YY1 proteins showed that quercetin could interact directly with YY1, and the binding of quercetin to YY1 significantly decreased the docking energy of YY1 with p53 protein. The interactions between quercetin and YY1 protein included direct binding and non-bonded indirect interactions, as confirmed by cellular thermal shift assay, UV-Vis absorption spectroscopy, fluorescence spectroscopy and circular dichroism spectroscopy. It was likely that quercetin directly bound to YY1 protein to compete with p53 for the binding sites of YY1 to disrupt the YY1-p53 interaction, thereby promoting p53 activation. This study provides insights into the mechanism underlying quercetin's anticancer action and supports the development of quercetin as an anticancer therapeutic agent.

The Potential Role of Apigenin in Cancer Prevention and Treatment

Cancer is the leading cause of death worldwide. In spite of advances in the treatment of cancer, currently used treatment modules including chemotherapy, hormone therapy, radiation therapy and targeted therapy causes adverse effects and kills the normal cells. Therefore, the goal of more effective and less side effects-based cancer treatment approaches is still at the primary position of present research. Medicinal plants or their bioactive ingredients act as dynamic sources of drugs due to their having less side effects and also shows the role in reduction of resistance against cancer therapy. Apigenin is an edible plant-derived flavonoid that has received significant scientific consideration for its health-promoting potential through modulation of inflammation, oxidative stress and various other biological activities. Moreover, the anti-cancer potential of apigenin is confirmed through its ability to modulate various cell signalling pathways, including tumor suppressor genes, angiogenesis, apoptosis, cell cycle, inflammation, apoptosis, PI3K/AKT, NF-κB, MAPK/ERK and STAT3 pathways. The current review mainly emphases the potential role of apigenin in different types of cancer through the modulation of various cell signaling pathways. Further studies based on clinical trials are needed to explore the role of apigenin in cancer management and explain the possible potential mechanisms of action in this vista.

Apigenin in cancer therapy: From mechanism of action to nano-therapeutic agent

Apigenin (APG) is a flavonoid presence in beverages, vegetables, and fruits containing anti-diabetic, anti-oxidant, and anti-viral activities, as well as cancer management properties. There is growing evidence that APG presented extensive anti-cancer effects in several cancer types by modulating various cellular processes, including angiogenesis, apoptosis, metastasis, autophagy, cell cycle, and immune responses, through activation or inhibition of different cell signaling pathways and molecules. By emerging nanotechnology and its advent in the biomedicine field, cancer therapy has been changed based on nanotechnology-based delivery systems. APG nanoformulations have been used to target tumor cells specifically, improve cellular uptake of APG, and overcome limitations of the free form of APG, such as low solubility and poor bioavailability. In this review, the biotherapeutic activity of APG and its mechanisms, both in free form and nanoformulation, toward cancer cells are discussed to shed some light on APG anti-tumor activity in different cancers.

Peroxisome proliferator-activated receptor gamma as a therapeutic target for hepatocellular carcinoma: Experimental and clinical scenarios

Hepatocellular carcinoma (HCC) is the most common type of liver cancer worldwide. Viral hepatitis is a significant risk factor for HCC, although metabolic syndrome and diabetes are more frequently associated with the HCC. With increasing prevalence, there is expected to be > 1 million cases annually by 2025. Therefore, there is an urgent need to establish potential therapeutic targets to cure this disease. Peroxisome-proliferator-activated receptor gamma (PPARγ) is a ligand-activated transcription factor that plays a crucial role in the patho-physiology of HCC. Many synthetic agonists of PPARγ suppress HCC in experimental studies and clinical trials. These synthetic agonists have shown promising results by inducing cell cycle arrest and apoptosis in HCC cells and preventing the invasion and metastasis of HCC. However, some synthetic agonists also pose severe side effects in addition to their therapeutic efficacy. Thus natural PPARγ agonists can be an alternative to exploit this potential target for HCC treatment. In this review, the regulatory role of PPARγ in the pathogenesis of HCC is elucidated. Furthermore, the experimental and clinical scenario of both synthetic and natural PPARγ agonists against HCC is discussed. Most of the available literature advocates PPARγ as a potential therapeutic target for the treatment of HCC.

Targeting cancer signaling pathways by natural products: Exploring promising anti-cancer agents

Cancer is one of the leading causes of death and significantly burdens the healthcare system. Due to its prevalence, there is undoubtedly an unmet need to discover novel anticancer drugs. The use of natural products as anticancer agents is an acceptable therapeutic approach due to accessibility, applicability, and reduced cytotoxicity. Natural products have been an incomparable source of anticancer drugs in the modern era of drug discovery. Along with their derivatives and analogs, natural products play a major role in cancer treatment by modulating the cancer microenvironment and different signaling pathways. These compounds are effective against several signaling pathways, mainly cell death pathways (apoptosis and autophagy) and embryonic developmental pathways (Notch pathway, Wnt pathway, and Hedgehog pathway). The historical record of natural products is strong, but there is a need to investigate the current role of natural products in the discovery and development of cancer drugs and determine the possibility of natural products being an important source of future therapeutic agents. Many target-specific anticancer drugs failed to provide successful results, which accounts for a need to investigate natural products with multi-target characteristics to achieve better outcomes. The potential of natural products to be promising novel compounds for cancer treatment makes them an important area of research. This review explores the significance of natural products in inhibiting the various signaling pathways that serve as drivers of carcinogenesis and thus pave the way for developing and discovering anticancer drugs.

Anticancer Effects and Molecular Mechanisms of Apigenin in Cervical Cancer Cells

Cervical cancer is the fourth most frequent malignancy in women. Apigenin is a natural plant-derived flavonoid present in common fruit, vegetables, and herbs, and has been found to possess antioxidant and anti-inflammatory properties as a health-promoting agent. It also exhibits important anticancer effects in various cancers, but its effects are not widely accepted by clinical practitioners. The present study investigated the anticancer effects and molecular mechanisms of apigenin in cervical cancer in vitro and in vivo. HeLa and C33A cells were treated with different concentrations of apigenin. The effects of apigenin on cell viability, cell cycle distribution, migration potential, phosphorylation of PI3K/AKT, the integrin β1-FAK signaling pathway, and epithelial-to-mesenchymal transition (EMT)-related protein levels were investigated. Mechanisms identified from the in vitro study were further validated in a cervical tumor xenograft mouse model. Apigenin effectively inhibited the growth of cervical cancer cells and cervical tumors in xenograft mice. Furthermore, the apigenin down-regulated FAK signaling (FAK, paxillin, and integrin β1) and PI3K/AKT signaling (PI3K, AKT, and mTOR), inactivated or activated various signaling targets, such as Bcl-2, Bax, p21^cip1, CDK1, CDC25c, cyclin B1, fibronectin, N-cadherin, vimentin, laminin, and E-cadherin, promoted mitochondrial-mediated apoptosis, induced G2/M-phase cell cycle arrest, and reduced EMT to inhibit HeLa and C33A cancer cell migration, producing anticancer effects in cervical cancer. Thus, apigenin may act as a chemotherapeutic agent for cervical cancer treatment.

Role of Induced Programmed Cell Death in the Chemopreventive Potential of Apigenin

The flavonoid apigenin (4′,5,7-trihydroxyflavone), which is one of the most widely distributed phytochemicals in the plant kingdom, is one of the most thoroughly investigated phenolic components. Previous studies have attributed the physiological effects of apigenin to its anti-allergic, antibacterial, antidiabetic, anti-inflammatory, antioxidant, antiviral, and blood-pressure-lowering properties, and its documented anticancer properties have been attributed to the induction of apoptosis and autophagy, the inhibition of inflammation, angiogenesis, and cell proliferation, and the regulation of cellular responses to oxidative stress and DNA damage. The most well-known mechanism for the compound’s anticancer effects in human cancer cell lines is apoptosis, followed by autophagy, and studies have also reported that apigenin induces novel cell death mechanisms, such as necroptosis and ferroptosis. Therefore, the aim of this paper is to review the therapeutic potential of apigenin as a chemopreventive agent, as well as the roles of programmed cell death mechanisms in the compound’s chemopreventive properties.

Studies related to the chemical composition, biological activities and toxicity of methanolic extracts of noni (Morinda citrifolia) fruits and leaves

Morinda citrifolia is a plant that grows in Brazilian northeast and presented a wide range of therapeutic, industrial and technological applications. Based on this, the aim of this work was to study the chemical composition, main biological activities and potential toxicity of its extracts, aiming their industrial application. Important compounds were identified in the methanolic extracts obtained by ultrasonic and Soxhlet extractions from leaves and fruits. GC × GC allowed for the identification of phytosterols, fatty acids and methyl esters, besides others (scopoletin, hydrocarbons, alcohols, terpenes). By HPLC-DAD, compounds like catechin, rutin, quercetin could be also identified and quantified. Their content of polyphenols and flavonoids was considered between the international standards. The extracts showed high antioxidant activities (EC₅₀ ∼ 300 μg mL^-1, using DPPH assay) compared with those from the literature. The extracts did not show toxicity or mutagenicity, but presented cytotoxicity, which can indicate their use safely in phytotherapic or nutritional applications.

Chrysin inhibits hepatocellular carcinoma progression through suppressing programmed death ligand 1 expression

BACKGROUNDS

The aberrant PD-L1 expression on cancer cells was confirmed to participate in immune evasion of hepatocellular carcinoma (HCC). Previous studies had documented that there were anti-tumorigenic effects of chrysin on HCC. However, whether chrysin can act on the over-expressed PD-L1 on HCC cells to exert the therapeutic effectiveness and the involved mechanisms has not yet been deciphered.

PURPOSE

Herein, we aimed to explore the regulatory effects of chrysin on the PD-1/PD-L1 immune checkpoint and investigate its possible mechanisms in vivo and in vitro.

METHODS

H22 xenograft mouse model was used to investigate the effects of chrysin on tumor growth and PD-L1 expression in tumors. In interferon-gamma (IFN-γ)-induced HepG2 cells, the cytotoxicity of chrysin was detected by MTT assay. Flow cytometry, ELISA and RT-PCR were carried out to evaluate the expression of PD-L1, and the expression of proteins in STAT3 and NF-κB pathways was also determined by Western blot. In HepG2 cells and Jurkat T cell co-culture system, ELISA kit was used to detect the level of IL-2, and T cell proliferation was further evaluated by CCK-8 method.

RESULTS

Our data suggested that chrysin could effectively inhibit the progression of tumor, and promote the anti-tumor immunity of mice concomitant with enhanced CD4/CD8-positive T cell proportion in tumor tissues of H22 xenograft mouse model. Additionally, chrysin significantly down-regulated the expression of PD-L1 in vivo and in vitro, which was closely associated with the blockage of STAT3 and NF-κB pathways. Moreover, in the co-culture system, chrysin could increase the proliferation of T cells and the concentration of IL-2.

CONCLUSION

These results indicate that chrysin may have the potential to be an immune checkpoint inhibitor for preventive or as an adjunctive curative agent for HCC.

ε-Viniferin and α-viniferin alone or in combination induced apoptosis and necrosis in osteosarcoma and non-small cell lung cancer cells

This study investigated the effects and molecular mechanisms of ε-viniferin and α-viniferin in non-small cell lung cancer cell line A549, melanoma cell line A2058, and osteosarcoma cell lines HOS and U2OS. Results showed ε-viniferin having antiproliferative effects on HOS, U2OS, and A549 cells. Compared with ε-viniferin at the same concentration, α-viniferin had higher antiproliferative effects on HOS cells, but not the same effect on U2OS and A549 cells. Lower dose combination of α-viniferin and ε-viniferin had more synergistic effects on A549 cells than either drug alone. α-Viniferin induced apoptosis in HOS cells by decreasing expression of phospho-c-Jun-N-terminal kinase 1/2 (p-JNK1/2) and increasing expression of cleaved Poly (ADP-ribose) polymerase (PARP), whereas α-viniferin in combination with ε-viniferin induced apoptosis in A549 cells by decreasing expression of phospho-protein kinase B (p-AKT) and increasing expression of cleaved PARP and cleaved caspase-3. ε-Viniferin and α-viniferin have not been studied using in vivo tumor models for cancer. This research is the first showing that ε-viniferin treatment resulted in significant inhibition of tumor growth in A549-cell xenograft-bearing nude mice compared with the control group. Consequently, ε-viniferin and α-viniferin may prove to be new approaches and effective therapeutic agents for osteosarcoma and lung cancer treatment.

Anti-Hepatocellular Carcinoma Biomolecules: Molecular Targets Insights

This report explores the available curative molecules directed against hepatocellular carcinoma (HCC). Limited efficiency as well as other drawbacks of existing molecules led to the search for promising potential alternatives. Understanding of the cell signaling mechanisms propelling carcinogenesis and driven by cell proliferation, invasion, and angiogenesis can offer valuable information for the investigation of efficient treatment strategies. The complexity of the mechanisms behind carcinogenesis inspires researchers to explore the ability of various biomolecules to target specific pathways. Natural components occurring mainly in food and medicinal plants, are considered an essential resource for discovering new and promising therapeutic molecules. Novel biomolecules normally have an advantage in terms of biosafety. They are also widely diverse and often possess potent antioxidant, anti-inflammatory, and anti-cancer properties. Based on quantitative structure-activity relationship studies, biomolecules can be used as templates for chemical modifications that improve efficiency, safety, and bioavailability. In this review, we focus on anti-HCC biomolecules that have their molecular targets partially or completely characterized as well as having anti-cancer molecular mechanisms that are fairly described.

Functionality of apigenin as a potent antioxidant with emphasis on bioavailability, metabolism, action mechanism and in vitro and in vivo studies: A review

Numerous diseases such as cancer, diabetes, cardiovascular, neurodegenerative diseases, etc. are linked with overproduction of reactive oxygen species (ROS) and oxidative stress. Apigenin (5,7,4'-trihydroxyflavone) is a widely distributed flavonoid, responsible for antioxidant potential and chelating redox active metals. Being present as glycosides or polymers, the apigenin degrades to variable amount in the digestive tract; during processing, its activity is also reduced due to high temperature or Fe/Cu addition. Although its metabolism remains elusive, enteric absorption occurs sufficiently to reduce plasma indices of oxidant status. Delayed clearance in plasma and slow liver decomposition enhance its systematic bioavailability. Antioxidant mechanism of apigenin includes: oxidant enzymes inhibition, modulation of redox signaling pathways (NF-kB, Nrf2, MAPK, and P13/Akt), reinforcing enzymatic and nonenzymatic antioxidant, metal chelation, and free radical scavenging. DPPH, ORAC, ABTS, and FRAP are the major in vitro methods for determining the antioxidant potential of apigenin, whereas its protective effects in whole and living cells of animals are examined using in vivo studies. Due to limited information on antioxidant potential of apigenin, its in vitro and in vivo antioxidant effects are, therefore, discussed with action mechanism and interaction with the signaling pathways. This paper concludes that apigenin is a potent antioxidant compound to overcome the difficulties related to oxidative stress and other chronic diseases.

Anticancer effects of the combined Thai noni juice ethanolic extracts and 5-fluorouracil against cholangiocarcinoma cells in vitro and in vivo

Application of 5-fluorouracil (5-FU) in cholangiocarcinoma (CCA) is limited by adverse side effects and chemoresistance. Therefore, the combination therapy of 5-FU with other substances, especially natural products may provide a new strategy for CCA treatment. The aim of this study was to evaluate the combination effects of 5-FU and two ethanolic extracts of Thai noni juice (TNJ) products on CCA cell lines and nude mice xenografts. The results of antiproliferative assay showed the combination treatment of 5-FU and each TNJ ethanolic extract exerted more cytotoxicity on CCA cells than either single agent treatment. Synergistic effects of drug combinations can enable the dose reduction of 5-FU. The mechanism underlying a combination treatment was apoptosis induction through an activation of p53 and Bax proteins. In the nude mouse xenograft model, combination treatments of 5-FU with each TNJ ethanolic extract suppressed the growth of CCA cells implanted mice more than single agent treatments with no effects on mouse body weight, kidney, and spleen. Moreover, low doses of TNJ ethanolic extracts reduced the hepatotoxicity of 5-FU in nude mice. Taken together, these data suggested that the ethanolic extracts of TNJ products can enhance the anti-CCA effect and reduce toxicity of 5-FU.

Emerging cellular and molecular mechanisms underlying anticancer indications of chrysin

Chrysin has been shown to exert several beneficial pharmacological activities. Chrysin has anti-cancer, anti-viral, anti-diabetic, neuroprotective, cardioprotective, hepatoprotective, and renoprotective as well as gastrointestinal, respiratory, reproductive, ocular, and skin protective effects through modulating signaling pathway involved in apoptosis, oxidative stress, and inflammation. In the current review, we discussed the emerging cellular and molecular mechanisms underlying therapeutic indications of chrysin in various cancers. Online databases comprising Scopus, PubMed, Embase, ProQuest, Science Direct, Web of Science, and the search engine Google Scholar were searched for available and eligible research articles. The search was conducted by using MeSH terms and keywords in title, abstract, and keywords. In conclusion, experimental studies indicated that chrysin could ameliorate cancers of the breast, gastrointestinal tract, liver and hepatocytes, bladder, male and female reproductive systems, choroid, respiratory tract, thyroid, skin, eye, brain, blood cells, leukemia, osteoblast, and lymph. However, more studies are needed to enhance the bioavailability of chrysin and evaluate this agent in clinical trial studies.

Apigenin role as cell-signaling pathways modulator: implications in cancer prevention and treatment

Cancer is a complex disease orchestrated by various extrinsic and intrinsic pathways. In recent years, there has been a keen interest towards the development of natural extracts-based cancer therapeutics with minimum adverse effects. In pursuit of effective strategy, a wide variety of natural products-derived compounds have been addressed for their anticancer effects. Apigenin is a naturally-occurring flavonoid present abundantly in various fruits and vegetables. Decades of research have delineated the pharmacological and biological properties of apigenin. Specifically, the apigenin-mediated anticancer activities have been documented in various types of cancer, but the generalized scientific evidence encompassing various molecular interactions and processes, such as regulation of the apoptotic machinery, aberrant cell signaling and oncogenic protein network have not been comprehensively covered. In this sense, in this review we have attempted to focus on the apigenin-mediated regulation of oncogenic pathways in various cancers. We have also addressed the cutting-edge research which has unveiled the remarkable abilities of apigenin to interact with microRNAs to modulate key cellular processes, with special emphasis on the nano-formulations of apigenin that can help their targeted delivery and can be a therapeutic solution for the treatment of various cancers.

Mechanism of Interactions of dsDNA Binding with Apigenin and Its Sulfamate Derivatives Using Multispectroscopic, Voltammetric, and Molecular Docking Studies

DNA binding investigations are critical for designing better pharmaceutical compounds since the binding of a compound to dsDNA in the minor groove is critical in drug discovery. Although only one in vitro study on the DNA binding mode of apigenin (APG) has been conducted, there have been no electrochemical and theoretical studies reported. We hereby report the mechanism of binding interaction of APG and a new class of sulfonamide-modified flavonoids, apigenin disulfonamide (ADSAM) and apigenin trisulfonamide (ATSAM), with deoxyribonucleic acid (DNA). This study was conducted using multispectroscopic instrumentation techniques, which include UV-vis absorption, thermal denaturation, fluorescence, and Fourier transform infrared (FTIR) spectroscopy, and electrochemical and viscosity measurement methods. Also, molecular docking studies were conducted at room temperature under physiological conditions (pH 7.4). The molecular docking studies showed that, in all cases, the lowest energy docking poses bind to the minor groove of DNA and the apigenin-DNA complex was stabilized by several hydrogen bonds. Also, π-sulfur interactions played a role in the stabilization of the ADSAM-DNA and ATSAM-DNA complexes. The binding affinities of the lowest energy docking pose (schematic diagram of table of content (TOC)) of APG-DNA, ADSAM-DNA, and ATSAM-DNA complexes were found to be -8.2, -8.5, and -8.4 kcal mol-1, respectively. The electrochemical binding constants K b were determined to be (1.05 × 105) ± 0.04, (0.47 × 105) ± 0.02, and (8.13 × 105) ± 0.03 for APG, ADSAM, and ATSAM, respectively (all of the tests were run in triplicate and expressed as the mean and standard deviation (SD)). The K b constants calculated for APG, ADSAM, and ATSAM are in harmony for all techniques. As a result of the incorporation of dimethylsulfamate groups into the APG structure, in the ADSAM-dsDNA and ATSAM-dsDNA complexes, in addition to hydrogen bonds, π-sulfur interactions have also contributed to the stabilization of the ligand-DNA complexes. This work provides new insights that could lead to the development of prospective drugs and vaccines.

Rationalizing the therapeutic potential of apigenin against cancer

BACKGROUND

Despite the remarkable advances made in the diagnosis and treatment of cancer during the past couple of decades, it remains the second largest cause of mortality in the world, killing approximately 9.6 million people annually. The major challenges in the treatment of the advanced stage of this disease are the development of chemoresistance, severe adverse effects of the drugs, and high treatment cost. Therefore, the development of drugs that are safe, efficacious, and cost-effective remains a 'Holy Grail' in cancer research. However, the research over the past four decades shed light on the cancer-preventive and therapeutic potential of natural products and their underlying mechanism of action. Apigenin is one such compound, which is known to be safe and has significant potential in the prevention and therapy of this disease.

AIM

To assess the literature available on the potential of apigenin and its analogs in modulating the key molecular targets leading to the prevention and treatment of different types of cancer.

METHOD

A comprehensive literature search has been carried out on PubMed for obtaining information related to the sources and analogs, chemistry and biosynthesis, physicochemical properties, biological activities, bioavailability and toxicity of apigenin.

KEY FINDINGS

The literature search resulted in many in vitro, in vivo and a few cohort studies that evidenced the effectiveness of apigenin and its analogs in modulating important molecular targets and signaling pathways such as PI3K/AKT/mTOR, JAK/STAT, NF-κB, MAPK/ERK, Wnt/β-catenin, etc., which play a crucial role in the development and progression of cancer. In addition, apigenin was also shown to inhibit chemoresistance and radioresistance and make cancer cells sensitive to these agents. Reports have further revealed the safety of the compound and the adaptation of nanotechnological approaches for improving its bioavailability.

SIGNIFICANCE

Hence, the present review recapitulates the properties of apigenin and its pharmacological activities against different types of cancer, which warrant further investigation in clinical settings.

Combination of Balsamin and Flavonoids Induce Apoptotic Effects in Liver and Breast Cancer Cells

Flavonoids such as naringenin, quercetin, and naringin are known to exhibit anticancer properties. In this study, we examined the effects of these flavonoids on cell viability and apoptotic pathways of cancer cells, either singly or in combination with the type 1 ribosome inactivating protein, Balsamin. Treatment with flavonoids (naringenin, quercetin, and naringin) plus Balsamin for 48 h reduced HepG2 and MCF-7 cell viability, increased the activation of caspase-3 and -8, and induced apoptosis through up-regulation of pro-apoptotic genes and down-regulation of anti-apoptotic genes. Out of the three flavonoids tested, the Balsamin-Naringenin and Balsamin-Quercetin combinations appeared to be most effective compared to the Balsamin-Naringin combination. Balsamin combined with flavonoids also activated endoplasmic reticulum (ER)-stress–mediated apoptosis in breast cancer (MCF-7) cells, which was not activated by Balsamin treatment alone. These experimental results showed that Balsamin combined with flavonoids can reduce HepG2 and MCF-7 cells viability and induce apoptosis, which could be considered as a promising therapeutic approach to sensitize cells to Balsamin treatment, thereby improving its efficacy in breast or liver cancer therapy.

Hispidulin: A promising flavonoid with diverse anti-cancer properties

In recent years, natural products have increasingly attracted more attention because of their potential anticancer activity and low intrinsic toxicity. Hispidulin is a natural flavonoid with a wide range of biological activities, including anti-inflammatory, antifungal, antiplatelet, anticonvulsant, anti-osteoporotic, and notably anticancer activities. Numerous in vivo and in vitro studies have shown that hispidulin, as a potential anticancer drug, affects cell proliferation, apoptosis, cell cycle, angiogenesis, and metastasis. Moreover, hispidulin exhibits synergistic anti-tumor effects when combined with some common clinical anticancer drugs (e.g., gemcitabine, 5-fluoroucil, sunitinib, temozolomide, and TRAIL). The combination of hispidulin and chemotherapeutic drugs reduces the efflux of chemotherapeutic drugs, enhances the chemosensitivity of cancer cells, and reverses drug resistance. Herein, we outlined the anticancer effects of hispidulin in various cancers and its intracellular molecular targets and related mechanisms of its anticancer activity. Based on the available literature, it can be established that hispidulin has significant potential to become an important complementary medicine for cancer prevention and treatment. However, more in-depth in vitro and in vivo studies should be conducted to support its translation from bench to bedside.

Natural and herbal compounds targeting breast cancer, a review based on cancer stem cells

Cancer stem cells (CSCs) are known as the major reason for therapy resistance. Recently, natural herbal compounds are suggested to have a significant role in inhibiting the breast cancer stem cells (BCSCs). The aim of this study was to explore the effective natural herbal compounds against BCSCs.This review article was designed based on the BCSCs, mechanisms of therapy resistance and natural herbal compounds effective to inhibit their activity. Therefore, Science direct, PubMed and Scopus databases were explored and related original articles were investigated from 2010 to 2019. BCSCs use different mechanisms including special membrane transporters, anti-apoptotic, pro-survival, and self-renewal- related signaling pathways. Natural herbal compounds could disturb these mechanisms, therefore may inhibit or eradicate the BCSCs. Studies show that a broad range of plants, either as a food or medicine, contain anti-cancer agents that phenolic components and their different derivatives share a large quantity. Natural herbal compounds play a pivotal role in the eradication of BCSCs, through the inhibition of biological activities and induction of apoptosis. Although it is necessary to conduct more clinical investigation.

Role of Flavonoids in the Prevention of AhR-Dependent Resistance During Treatment with BRAF Inhibitors

BRAF and MEK inhibitors (BRAFi and MEKi) are the standard of care for the treatment of metastatic melanoma in patients with BRAF^V600E mutations, greatly improving progression-free survival. However, the acquisition of resistance to BRAFi and MEKi remains a difficult clinical challenge, with limited therapeutic options available for these patients. Here, we investigated the therapeutic potential of natural flavonoids as specific AhR (Aryl hydrocarbon Receptor) transcription factor antagonists in combination with BRAFi. Experimental Design: Experiments were performed in vitro and in vivo with various human melanoma cell lines (mutated for BRAF^V600E) sensitive or resistant to BRAFi. We evaluated the role of various flavonoids on cell sensitivity to BRAFi and their ability to counteract resistance and the invasive phenotype of melanoma. Results: Flavonoids were highly effective in potentiating BRAFi therapy in human melanoma cell lines by increasing sensitivity and delaying the pool of resistant cells that arise during treatment. As AhR antagonists, flavonoids counteracted a gene expression program associated with the acquisition of resistance and phenotype switching that leads to an invasive and EMT-like phenotype. Conclusions: The use of natural flavonoids opens new therapeutic opportunities for the treatment of patients with BRAF-resistant disease.

Cartilage Oligomeric Matrix Protein promotes epithelial-mesenchymal transition by interacting with Transgelin in Colorectal Cancer

Background and Purpose: The role of the cartilage oligomeric matrix protein (COMP) in epithelial-mesenchymal transition (EMT) in tumor progression has been studied, but its exact regulatory mechanism remains unknown.

Methods: The interaction between COMP and the actin-binding protein transgelin (TAGLN) was identified by interaction protein prediction and co-immunoprecipitation and verified through the stochastic optical reconstruction microscopy (STORM) and duolink experiments. Western blot and immunofluorescence analyses were conducted to detect the changes in EMT-related markers after COMP overexpression and knockdown. Molecular docking and Biacore of the interaction interface of COMP/TAGLN revealed that Chrysin directly targeted COMP. The promotion of COMP and the Chrysin inhibition of EMT were detected through the cell migration, invasion, apoptosis, and xenotransplantation of nude mice.

Results: COMP interacts with TAGLN in EMT in colorectal cancer to regulate cytoskeletal remodeling and promote malignant progression. COMP is highly expressed in highly malignant colorectal cancer and positively correlated with TAGLN expression. COMP knockdown can inhibit colorectal cancer metastasis and invasion, whereas COMP overexpression promotes EMT in colorectal cancer. Through virtual screening of the protein interaction interface, Chrysin, a flavonoid compound extracted from Oroxylum indicum, was found to have the highest docking score to the COMP/TAGLN complex. Chrysin inhibited COMP, thereby preventing EMT and the malignant progression of colorectal cancer.

Conclusions: This study illustrated the role of COMP in EMT and suggested that COMP/TAGLN may be a potential tumor therapeutic target. Chrysin exhibits obvious antitumor effects. This work provides a preliminary antitumor therapy to target COMP or its interaction protein to inhibit EMT.

Overcoming the hypoxia-induced drug resistance in liver tumor by the concurrent use of apigenin and paclitaxel

The chemotherapeutic efficacy of paclitaxel against hypoxic tumors is usually unsatisfactory, which is partially due to the so-called hypoxia-induced drug resistance. The mechanism of hypoxia-induced resistance is primarily associated with hypoxia-inducible factor 1α (HIF-1α), which is an oxygen-sensitive transcriptional activator coordinating the cellular response to hypoxia. Apigenin is a natural occurring HIF-1α inhibitor that can suppress the expression of HIF-1α through multiple pathways and reverse the hypoxia-induced resistance found in cancer cells. Here we report that the use of apigenin can suppress the HIF-1α expression in hypoxic tumors through the simultaneous inhibition of the AKT/p-AKT pathway and HSP90, which is beneficial for enhancing the anticancer activity of the co-administered paclitaxel. The potential synergistic effect of apigenin and paclitaxel was further validated on HepG2 cell line and tumor-bearing mouse models.

Apigenin as an anticancer agent

Apigenin is an edible plant-derived flavonoid that has been reported as an anticancer agent in several experimental and biological studies. It exhibits cell growth arrest and apoptosis in different types of tumors such as breast, lung, liver, skin, blood, colon, prostate, pancreatic, cervical, oral, and stomach, by modulating several signaling pathways. Apigenin induces apoptosis by the activation of extrinsic caspase-dependent pathway by upregulating the mRNA expressions of caspase-3, caspase-8, and TNF-α. It induces intrinsic apoptosis pathway as evidenced by the induction of cytochrome c, Bax, and caspase-3, while caspase-8, TNF-α, and B-cell lymphoma 2 levels remained unchanged in human prostate cancer PC-3 cells. Apigenin treatment leads to significant downregulation of matrix metallopeptidases-2, -9, Snail, and Slug, suppressing invasion. The expressions of NF-κB p105/p50, PI3K, Akt, and the phosphorylation of p-Akt decreases after treatment with apigenin. However, apigenin-mediated treatment significantly reduces pluripotency marker Oct3/4 protein expression which might be associated with the downregulation of PI3K/Akt/NF-κB signaling.

Investigation of possible effects of apigenin, sorafenib and combined applications on apoptosis and cell cycle in hepatocellular cancer cells

Hepatocellular carcinoma (HCC) is the most common type of liver tumors. There is only one chemodrug for treatment called sorafenib that is an effective multikinase inhibitor. However, most of the patients gain resistance to sorafenib treatment in six months. Thus, there is a limitation for treatment of HCC. Apigenin is a natural flavonoid that has been used for many years as an antioxidant and anti-inflammatory agent. The aim of this study is to investigate the combined therapeutic effects of sorafenib and apigenin upon apoptosis and cell cycle on HepG2 cell line. Cytotoxic effects of sorafenib and apigenin on HepG2 cells were determined by XTT assay. Effects of single and combined treatment on cell migration, invasion and colony formation were analysed by wound healing, transwell matrigel invasion assay and colony formation assay, respectively. TUNEL assay was performed for analyse apoptosis rates. Expression changes of genes related with apoptosis and cell cycle were analysed by quantitative real-time PCR. Combined treatment of sorafenib and apigenin has more decreasing effects on cell viability than single treatment groups. Also, combination group caused significant increase of apoptotic cells. Migration and invasion capability of cells in combined treatment group are decreased. Lastly, quantitative real-time PCR results showed that combination of both drugs arrested cell cycle and increased apoptotic gene expressions more than single treatment groups. This is the first study that investigating the combined treatment of sorafenib and apigenin on HCC in vitro. By combined treatment, apigenin potentiates sorafenib cytotoxicity on HepG2 cells. Effects of combined treatment on migration, invasion, apoptosis and gene expressions showed that may sorafenib and apigenin have synergistic effect.

Therapeutic potential of PPARγ natural agonists in liver diseases

Peroxisome proliferator‐activated receptor gamma (PPARγ) is a vital subtype of the PPAR family. The biological functions are complex and diverse. PPARγ plays a significant role in protecting the liver from inflammation, oxidation, fibrosis, fatty liver and tumours. Natural products are a promising pool for drug discovery, and enormous research effort has been invested in exploring the PPARγ‐activating potential of natural products. In this manuscript, we will review the research progress of PPARγ agonists from natural products in recent years and probe into the application potential and prospects of PPARγ natural agonists in the therapy of various liver diseases, including inflammation, hepatic fibrosis, non‐alcoholic fatty liver and liver cancer.

Indian Morinda species: A review

Morinda is a largest genus of Rubiaceae family, and its 11 species are found in India. In India, plant species are known by several common names as great morinda, Indian mulberry, noni, beach mulberry and cheese fruit. Various Morinda products (capsules, tablets, skin products and fruit juices) are available in the market, used by people for treatment of several health complaints. A diversity of phytochemicals including iridoids, flavonoids, flavonoid glycosides, anthraquinones, coumarins, lignanas, noniosides, phenolics and triterpenoids have been reported from Morinda species. Morinda species are used in the treatment of inflammation, cancer, diabetes, psyquiatric disorders, and bacterial and viral infections. The noni fruit juice (Morinda citrifolia) and its products are used clinically in the treatment of cancer, hypertension and cervical spondylosis affecting patients. M. citrifolia fuit juice, with different doses, is used in the maintaining blood pressure and reducing of superoxides, HDL and LDL levels. Similarly, oligosaccharide capsules and tablets of root extract of M. officinalis are recommended as medicine for the treatment of kidney problems and sexual dysfunctions of patients. The toxicological studies revealed that higher doses of fruit juice (4,000 or 5,000 mg/kg) of M. citrifolia for 2 or more months cause toxic effects on liver and kidneys. M. officinalis root extracts (ethanolic and aqueous) are found fully safe during treatment of diseases. A large number of reviews are available on M. citrifolia but very few studies are conducted on other Indian Morinda species. This review reports the comprehensive knowledge on state-wise distribution, botany, ethnomedicinal uses, phytochemistry, pharmacological activities, clinical applications and toxicological evaluations of 11 species of Morinda found in India.

Effects of flavonoids on tongue squamous cell carcinoma

Squamous cell carcinoma (SCC) of the tongue is associated with tobacco use, alcohol abuse, and human papillomavirus (HPV) infections. While clinical outcomes have recently improved for HPV-positive patients in general, 50% of patients suffering from tongue cancer die within 5 years of being diagnosed. Flavonoids are secondary plant metabolites with a wide range of biological activities including antioxidant, anti-inflammatory, and anticancer activities. Flavonoids have generated high interest as therapeutic agents owing to their low toxicity and their effects on a large variety of cancer cell types. In this literature review, we evaluate the actions of flavonoids on SCC of the tongue demonstrated in both in vivo and in vitro models.

Apigenin, a flavonoid constituent derived from P. villosa, inhibits hepatocellular carcinoma cell growth by CyclinD1/CDK4 regulation via p38 MAPK-p21 signaling

Hepatocellular carcinoma (HCC) is a leading cause of cancer mortality worldwide. Apigenin was widely used in HCC treatment; however, the detailed mechanisms have not been clarified. We isolated, characterized, and identified Apigenin from the P. villosa plant using ethanol-extracted, semi-preparative HPLC and NMR. MTT was used to detect the cytotoxicity of Apigenin in HepG2, SMMC-7721 and Huh-7 cell lines. The cell cycle changes of Apigenin on HepG2 using flow cytometry and the key molecules of cell cycle regulation by RT-qPCR and Western blot. Apigenin was ethanol-extracted and semi-preparative HPLC was used for isolation and purification. The compounds were identified and the results showed Apigenin was one of the bioactive compounds. Apigenin exhibited relatively high cytotoxicity in HepG2, SMMC-7721, and Huh-7. Cell cycle analysis showed that Apigenin could induce G1 arrest in HepG2 in a dose-dependent manner. CyclinD1 was up-regulated and CDK4 was down-regulated upon Apigenin treatment, which indicated that Apigenin could block cell cycle progression at the G1 phase though the regulation of CDK4 and CyclinD1 expression. In conclusion, the present findings might provide new insights about the implication of Apigenin and P. villosa in cancer therapy.

Apigenin Inhibits IL-6 Transcription and Suppresses Esophageal Carcinogenesis

Esophagus cancer is the seventh cause of cancer-related deaths globally. In this study, we analyzed interleukin 6 (IL-6) gene expression in human esophagus cancer patients and showed that IL-6 mRNA levels are significantly higher in tumor tissues and negatively correlated with overall survival, suggesting that IL-6 is a potential therapeutic target for esophagus cancer. We further demonstrated that apigenin, a nature flavone product of green plants, inhibited IL-6 transcription and gene expression in human esophagus cancer Eca-109 and Kyse-30 cells. Apigenin significantly and dose-dependently inhibited cell proliferation and promoted apoptosis while stimulating the cleaved PARP (poly ADP-ribose polymerase) (C-PARP) and caspase-8 expression. It suppressed VEGF (Vascular endothelial growth Factor) expression and tumor-induced angiogenesis. Pretreatment of cells with IL-6 could completely reverse apigenin-induced cellular changes. Finally, using a preclinical nude mice model subcutaneously xenografted with Eca-109 cells, we demonstrated the in vivo antitumor activity and mechanisms of apigenin. Taken together, this study revealed for the first time that apigenin is a new IL-6 transcription inhibitor and that inhibiting IL-6 transcription is one of the mechanisms by which apigenin exhibits its anticancer effects. The potential clinical applications of apigenin in treating esophagus cancer warrant further investigations.

Potential Role of Flavonoids in Treating Chronic Inflammatory Diseases with a Special Focus on the Anti-Inflammatory Activity of Apigenin

Inflammation has been reported to be intimately linked to the development or worsening of several non-infectious diseases. A number of chronic conditions such as cancer, diabetes, cardiovascular disorders, autoimmune diseases, and neurodegenerative disorders emerge as a result of tissue injury and genomic changes induced by constant low-grade inflammation in and around the affected tissue or organ. The existing therapies for most of these chronic conditions sometimes leave more debilitating effects than the disease itself, warranting the advent of safer, less toxic, and more cost-effective therapeutic alternatives for the patients. For centuries, flavonoids and their preparations have been used to treat various human illnesses, and their continual use has persevered throughout the ages. This review focuses on the anti-inflammatory actions of flavonoids against chronic illnesses such as cancer, diabetes, cardiovascular diseases, and neuroinflammation with a special focus on apigenin, a relatively less toxic and non-mutagenic flavonoid with remarkable pharmacodynamics. Additionally, inflammation in the central nervous system (CNS) due to diseases such as multiple sclerosis (MS) gives ready access to circulating lymphocytes, monocytes/macrophages, and dendritic cells (DCs), causing edema, further inflammation, and demyelination. As the dearth of safe anti-inflammatory therapies is dire in the case of CNS-related disorders, we reviewed the neuroprotective actions of apigenin and other flavonoids. Existing epidemiological and pre-clinical studies present considerable evidence in favor of developing apigenin as a natural alternative therapy against chronic inflammatory conditions.

Pinocembrin-Enriched Fractions of Elytranthe parasitica (L.) Danser Modulates Apoptotic and MAPK Cellular Signaling in HepG2 Cells

Background:

Hepatocellular carcinoma (HCC) is the fifth leading cause of cáncer mortality. Elytranthe parasitica (L.) Danser (EP), a hemiparasitic plant (Loranthaceae) has potent anti-cancer properties.

Objective:

In the study, we investigated the effect of EP fractions on the expression of apoptosis and mitogenactivated protein kinase (MAPK) markers deregulated in HCC. Bioactivity fractionation was performed to isolate the phytochemical(s) exerting anti-tumor activity in HepG2 cells.

Method:

Anti-proliferative, clonogenic and anti-metastatic effects of EP fractions were examined in hepatocellular carcinoma cell line, HepG2 by Sulphorhodamine B, colony formation and scratch wound assays respectively in hepatocellular cell line, HepG2. The effects of EP fractions on key markers of apoptosis and MAPK signaling pathways were explored. </P><P> Key findings: EP bioactive fractions showed significant anti-tumor potential, reduced clonogenicity and considerably inhibited cell migration in HepG2 cells in vitro. The fractions augmented annexin V binding and induced apoptosis by causing cell cycle arrest at G2/M and S phase checkpoints. The fractions increased expression levels of p53, bad, cleaved PARP (Poly ADP ribose polymerase) and cleaved Caspase-3. Expression levels of phosphorylated ERK1/2 (Extracellular signal-regulated kinase) were downregulated. Pinocembrin-7-O-ß-D-glucoside and chrysin were isolated and characterized for the first time from Elytranthe parasitica (L.) Danser.

Conclusion:

Our findings reveal that EP fractions induced cell cycle arrest and triggered apoptosis in HepG2 cells by upregulating apoptosis and deactivating MAPK pathway. It signifies that pinocembrin glycoside and chrysin are bioactive phytochemicals contributing to the potent anti-hepatocarcinoma effects on HepG2 cells. Hence, bioactive EP fractions could be used as a therapeutic agent for effective HCC therapy.

Effect of Morinda citrifolia and Annona muricata on Erhlich Tumor Cells in Swiss Albino Mice and In Vitro Fibroblast Cells

Morinda citrifolia (MC) and Annona muricata (AM) are popularly used for the treatment of several diseases, including cancer. Our objective was to evaluate the effects of the juice of the MC fruit, and the ethanolic extract of AM leaves on Erhlich tumor cells, in mice and in vitro fibroblastic cells. The animals were divided into G1 and G2: controls; G3: treated with AM, and G4 juice: treated with MC. The animals were subjected to intraperitoneal inoculation of 10³ tumor cells and then treated with the plants. G1 and G2 received a saline solution. Cells were grown in RPMI 1640 medium, supplemented with 10% fetal bovine serum, and maintained at 37°C in 5% CO₂ atmosphere. After growth, the cells were trypsinized and incubated again. Subsequently, serial dilution of extracts and juice was performed and incubated again for 48 h. We evaluated the ascites growth, the survival rate, and cytotoxicity in fibroblast cells. AM and MC did not interfere in the ascites pattern. MC, but not AM showed significance in the survival rate. Both AM and MC produced cytotoxicity activity in T3T cells. Despite advances in medicine, cancer is still one of the leading causes of death in the world and traditional medications are not always effective. The use of MC may bring beneficial effects to patients since they interfere with different mechanisms of action during carcinogenesis. However, we suggest that further investigations should be performed.

Chrysin induces cell growth arrest, apoptosis, and ER stress and inhibits the activation of STAT3 through the generation of ROS in bladder cancer cells

Chrysin is a natural flavone that has various biological activities, including antitumor effects. However, the effect of chrysin on bladder cancer cells remains elusive. The present study investigated the effects of chrysin on bladder cancer cells and its underlying mechanisms. The results demonstrated that chrysin induced apoptosis via the intrinsic pathway, as evidenced by activation of caspase-9 and caspase-3, however not caspase-8. In addition, chrysin reduced the expression of anti-apoptotic B cell lymphoma (Bcl) proteins including Bcl-2, Mcl-1, Bcl-xl, and promoted the protein expression of pro-apoptotic Bcl-2 associated X, apoptosis regulator. Chrysin also induced endoplasmic reticulum stress via activation of the unfolded protein response of PRKR-like endoplasmic reticulum kinase, eIF2α and activating transcription factor 4 in bladder cancer cells. Additionally, chrysin inhibited the signal transducer and activator of transcription 3 pathway. Furthermore, the generation of reactive oxygen species (ROS) was detected following treatment with chrysin. The ROS scavenger N-acetylcysteine inhibited the antitumor effect of chrysin. Collectively, these results indicate chrysin may act as a promising therapeutic candidate for targeting bladder cancer.