The Phenolic compound Kaempferol overcomes 5-fluorouracil resistance in human resistant LS174 colon cancer cells

Potential Strategies for Overcoming Drug Resistance Pathways Using Propolis and Its Polyphenolic/Flavonoid Compounds in Combination with Chemotherapy and Radiotherapy

Conventional cancer treatments include surgical resection, chemotherapy, hyperthermia, immunotherapy, hormone therapy, and locally targeted therapies such as radiation therapy. Standard cancer therapies often require the use of multiple agents, which can activate nuclear factor kappa B (NF-κB) in tumor cells, leading to reduced cell death and increased drug resistance. Moreover, the use of multiple agents also contributes to added toxicity, resulting in poor treatment outcomes. Cancer cells gradually develop resistance to almost all chemotherapeutics through various mechanisms, such as drug efflux, alterations in drug metabolism and transport, changes in signal transduction pathways, enhanced DNA repair capacity, evasion of apoptosis, increased mutations, reactivation of drug targets, interaction with the cancer microenvironment, cancer cell-stroma interactions, epithelial-mesenchymal transition (EMT)-mediated chemoresistance, epigenetic modifications, metabolic alterations, and the effect of cancer stem cells (CSCs). Developing new strategies to improve chemotherapy sensitivity while minimizing side effects is essential for achieving better therapeutic outcomes and enhancing patients' quality of life. One promising approach involves combining conventional cancer treatments with propolis and its flavonoids. These natural compounds may enhance tumor response to treatment while reducing toxicity. Propolis and its components can sensitize cancer cells to chemotherapeutic agents, likely by inhibiting NF-κB activation, reprogramming tumor-associated macrophages (TAMs; an M2-like phenotype), and thereby reducing the release of matrix metalloproteinase (MMP)-9, cytokines, chemokines, and the vascular endothelial growth factor (VEGF). By reducing TAMs, propolis and its components may also overcome EMT-mediated chemoresistance, disrupt the crosstalk between macrophages and CSCs, inhibit the maintenance of stemness, and reverse acquired immunosuppression, thus promoting an antitumor response mediated by cytotoxic T-cells. This review highlights the potential of flavonoids to modulate the responsiveness of cancer to conventional treatment modalities. The evidence suggests that novel therapeutic strategies incorporating flavonoids could be developed to improve treatment outcomes. The positive effects of combining propolis with chemotherapeutics include reduced cytotoxicity to peripheral blood leukocytes, liver, and kidney cells. Therefore, polyphenolic/flavonoid components may hold potential for use in combination with chemotherapeutic agents in the clinical treatment of various types of cancers.

The Anticancer Effects and Therapeutic Potential of Kaempferol in Triple-Negative Breast Cancer

Breast cancer is the second-leading cause of cancer death among women in the United States. Triple-negative breast cancer (TNBC), a subtype of breast cancer, is an aggressive phenotype that lacks estrogen (ER), progesterone (PR), and human epidermal growth (HER-2) receptors, which is challenging to treat with standardized hormonal therapy. Kaempferol is a natural flavonoid with antioxidant, anti-inflammatory, neuroprotective, and anticancer effects. Besides anti-tumorigenic, antiproliferative, and apoptotic effects, kaempferol protects non-cancerous cells. Kaempferol showed anti-breast cancer effects by inducing DNA damage and increasing caspase 3, caspase 9, and pAMT expression, modifying ROS production by Nrf2 modulation, inducing apoptosis by increasing cleaved PARP and Bax and downregulating Bcl-2 expression, inducing cell cycle arrest at the G2/M phase; inhibiting immune evasion by modulating the JAK-STAT3 pathway; and inhibiting the angiogenic and metastatic potential of tumors by downregulating MMP-3 and MMP-9 levels. Kaempferol holds promise for boosting the efficacy of anticancer agents, complementing their effects, or reversing developed chemoresistance. Exploring novel TNBC molecular targets with kaempferol could elucidate its mechanisms and identify strategies to overcome limitations for clinical application. This review summarizes the latest research on kaempferol's potential as an anti-TNBC agent, highlighting promising but underexplored molecular pathways and delivery challenges that warrant further investigation to achieve successful clinical translation.

Synergistic Mechanisms of Selected Polyphenols in Overcoming Chemoresistance and Enhancing Chemosensitivity in Colorectal Cancer

Colorectal cancer (CRC) is a leading cause of cancer deaths worldwide. Despite significant advances in medical treatment, chemotherapy as monotherapy can lead to substantial side effects and chemoresistance. This underscores the need for therapeutic approaches that are not only pharmacologically safe but also modulate multiple potent signaling pathways and sensitize cancer cells to overcome resistance to standard drugs. In recent years, scientists have been searching for natural compounds that can be used as chemosensitizers in addition to conventional medications for the synergistic treatment of CRC. Polyphenols represent a diverse group of natural compounds that can target multiple signaling pathways in cancer cells to induce anti-cancer effects. Additionally, polyphenols have been shown to work synergistically with chemotherapeutics and other natural compounds in cancer cells. This review aims to provide a comprehensive insight into the synergistic mechanisms of selected polyphenols as chemosensitizers in CRC cells. Further research and clinical trials are warranted to fully harness the synergistic mechanisms of selected polyphenols combined with chemotherapy or natural compounds in improving cancer treatment outcomes.

The interplay of exercise and polyphenols in cancer treatment: A focus on oxidative stress and antioxidant mechanisms

Exercise has been demonstrated to induce an elevated production of free radicals, leading to the onset of oxidative stress. Numerous studies highlight the positive impacts of aerobic exercise, primarily attributed to the increase in overall antioxidant capacity. The evidence suggests that engaging in aerobic exercise contributes to a reduction in the likelihood of advanced cancer and mortality. Oxidative stress occurs when there is an imbalance between the generation of free radicals and the collective antioxidant defense system, encompassing both enzymatic and nonenzymatic antioxidants. Typically, oxidative stress triggers the formation of reactive oxygen or nitrogen species, instigating or advancing various issues in cancers and other diseases. The pro-oxidant-antioxidant balance serves as a direct measure of this imbalance in oxidative stress. Polyphenols contain a variety of bioactive compounds, including flavonoids, flavanols, and phenolic acids, conferring antioxidant properties. Previous research highlights the potential of polyphenols as antioxidants, with documented effects on reducing cancer risk by influencing processes such as proliferation, angiogenesis, and metastasis. This is primarily attributed to their recognized antioxidant capabilities. Considering the extensive array of signaling pathways associated with exercise and polyphenols, this overview will specifically focus on oxidative stress, the antioxidant efficacy of polyphenols and exercise, and their intricate interplay in cancer treatment.

Unravelling the molecular mechanistic pathway underlying the anticancer effects of kaempferol in colorectal cancer: a reverse pharmacology network approach

Colorectal cancer (CRC) is the third most diagnosed and highly fatal malignancy, presenting serious health concerns worldwide. The search for an effective cure for CRC is challenging and poses a serious concern. Kaempferol is a potent anti-cancerous bioactive compound often suggested for treating various cancers, including CRC. However, its underlying molecular mechanism against CRC remains unclear. The present study delves into kaempferol's molecular pathways and underlying molecular mechanisms against CRC targets. The target protein-coding genes for kaempferol were retrieved, and the CRC-associated genes were curated. Twelve common targets with a disease specificity index of > 0.6 were validated for their protein expression at different stages of CRC. Over-expressed USP1, SETD7, POLH, TDP1 and RACGAP1 were selected for further studies. The binding affinities of kaempferol to the corresponding proteins were evaluated using molecular docking and Molecular Dynamics (MD) simulations. SETD7 exhibited the highest binding affinity with the lowest binding energy (- 8.06 kcal/mol). Additionally, the MD simulation, and MM-PBSA conferred SETD7-kaempferol complex had the least root-mean-square deviation with lower interaction energy and higher conformational stability. The protein-protein interaction of SETD7 constructed revealed direct interactors, namely, DNMT1, FOXO1, FOXO3, FOXO4, H3-3B, H3-4, H3C12, H3C13, SETD7, SIRT1 and TP53, have a potential role in cancer progression through FOXO signalling. In summary, our study revealed kaempferol's multi-target and synergistic effect on multiple CRC targets and its underlying mechanisms. Finally, the study recommends in-vitro and in-vivo trials for validation of anti-cancerous drugs for CRC.

Efficacy and safety of Piwei Peiyuan Prescription in the treatment of chronic atrophic gastritis: A multicenter, double-blind, double-simulated, randomized, controlled clinical trial

The incidence of chronic atrophic gastritis (CAG) is on the rise due to the growing pressure in modern social life, increasing bad living habits and emotional disorders (such as anxiety and depression), and the aging of the population. Of note, digestive system diseases are the dominant diseases in the field of traditional Chinese medicine (TCM). Therefore, this study evaluated the efficacy and safety of Piwei Peiyuan Prescription, a TCM prescription, in the treatment of CAG through a multicenter, double-blind, randomized, controlled design. This research was organized by the Second Affiliated Hospital of Anhui University of TCM and simultaneously performed in 6 centers. A total of 120 CAG patients were included and randomized into 2 groups: group A (treatment with Piwei Peiyuan granules plus Weifuchun Simulant) and Group B (treatment with Weifuchun Tablets plus Piwei Peiyuan Simulant). These 2 groups were compared in terms of gastroscopy scores, TCM syndrome scores, and serological indicators at baseline and within 12 weeks after treatment. According to endoscopic biopsy for pathological observation, atrophy (2.56 ± 1.08 vs 3.00 ± 1.00, P = .028) and intestinal epithelial hyperplasia (1.00 ± 1.43 vs 1.69 ± 1.80, P = .043) scores were lower in group A than in group B. For the more, group A had higher effective rates for inflammation, atrophy, and intestinal metaplasia (IM) in various regions of the stomach, especially for atrophy/IM of the gastric angle (64%, P = .034) and atrophy/IM of the lesser curvature of gastric antrum (63%, P = .042) than group B. According to TCM syndrome scores, Piwei Peiyuan Prescription improved the scores of gastric distension (2.30 ± 1.13 vs 2.80 ± 0.99, P = .022), preference for warmth and pressure (1.44 ± 1.06 vs 1.36 ± 1.10, P = .041), and poor appetite and indigestion (0.78 ± 0.66 vs 1.32 ± 0.72, P = .018). GAS, MTL, and PGE2 expression was significantly elevated after treatment with Piwei Peiyuan Prescription (P < .001). Piwei Peiyuan Prescription is effective for CAG treatment with high safety.

The Role of Phytonutrient Kaempferol in the Prevention of Gastrointestinal Cancers: Recent Trends and Future Perspectives

In recent years, kaempferol, a natural flavonoid present in various fruits and vegetables, has received significant attention in gastrointestinal cancer research due to its varied therapeutic effects. Kaempferol has been proven to alter several molecular mechanisms and pathways, such as the PI3/Akt, mTOR, and Erk/MAPK pathway involved in cancer progression, showing its inhibitory effects on cell proliferation, survival, angiogenesis, metastasis, and migration. Kaempferol is processed in the liver and small intestine, but limited bioavailability has been a major concern in the clinical implications of kaempferol. Nano formulations have been proven to enhance kaempferol's efficacy in cancer prevention. The synergy of nanotechnology and kaempferol has shown promising results in in vitro studies, highlighting the importance for more in vivo research and clinical trials to determine safety and efficacy. This review aims to focus on the role of kaempferol in various types of gastrointestinal cancer and how the combination of kaempferol with nanotechnology helps in improving therapeutic efficacy in cancer treatment.

Unveiling the anti-inflammatory potential of Acalypha indica L. and analyzing its research trend: digging deep to learn deep

The plant Acalypha indica L. is a well-known traditional plant belonging to the family Euphorbiaceae. Traditional practices of the plant claim to treat asthma, pneumonia, wound healing, rheumatoid arthritis, bronchitis, and skin disorders. The major phytochemicals reported are cyanogenic glucosides, tannins, coumarins, flavonoid glycosides, fatty acids, and volatile oils. To summarize the anti-inflammatory potential of Acalypha indica extract and its phytochemicals through preclinical studies. The search terms include anti-inflammatory, Acalypha indica, and Acalypha indica extract independently or in combination with pro-inflammatory markers using various databases, including Scopus, Web of Science, PubMed, ProQuest, and Google Scholar. The results of preclinical studies confirm that Acalypha indica exhibits strong anti-inflammatory activity. Most of the experimental studies that have been conducted on plant extract are protein denaturation, human red blood cell membrane stabilization assay, and carrageenan-induced inflammation models. However, the molecular mechanism in these studies is still unclear to demonstrate its anti-inflammatory effects. Acalypha indica possesses anti-inflammatory effects that may be due to the presence of phenolic compounds especially flavonoids present in the Acalypha indica. Thus, further research is needed, to understand mechanistic insights of the plant phytochemicals to represent anti-inflammatory properties.

Natural products reverse cancer multidrug resistance

Cancer stands as a prominent global cause of death. One of the key reasons why clinical tumor chemotherapy fails is multidrug resistance (MDR). In recent decades, accumulated studies have shown how Natural Product-Derived Compounds can reverse tumor MDR. Discovering novel potential modulators to reduce tumor MDR by Natural Product-Derived Compounds has become a popular research area across the globe. Numerous studies mainly focus on natural products including flavonoids, alkaloids, terpenoids, polyphenols and coumarins for their MDR modulatory activity. Natural products reverse MDR by regulating signaling pathways or the relevant expressed protein or gene. Here we perform a deep review of the previous achievements, recent advances in the development of natural products as a treatment for MDR. This review aims to provide some insights for the study of multidrug resistance of natural products.

Natural bioactive compounds and FOXO3a in cancer therapeutics: An update

Forkhead box protein 3a (FOXO3a) is a transcription factor that regulates various downstream targets upon its activation, leading to the upregulation of tumor suppressor and apoptotic pathways. Hence, targeting FOXO3a is an emerging strategy for cancer prevention and treatment. Recently, Natural Bioactive Compounds (NBCs) have been used in drug discovery for treating various disorders including cancer. Notably, several NBCs have been shown as potent FOXO3a activators. NBCs upregulate FOXO3a expressions through PI3K/Akt, MEK/ERK, AMPK, and IκB signaling pathways. FOXO3a promotes its anticancer effects by upregulating the levels of its downstream targets, including Bim, FasL, and Bax, leading to apoptosis. This review focuses on the dysregulation of FOXO3a in carcinogenesis and explores the potent FOXO3a activating NBCs for cancer prevention and treatment. Additionally, the review evaluates the safety and efficacy of NBCs. Looking ahead, NBCs are anticipated to become a cost-effective, potent, and safer therapeutic option for cancer, making them a focal point of research in the field of cancer prevention and treatment.

The Anticancer Potential of Kaempferol: A Systematic Review Based on In Vitro Studies

Given the heterogeneity of different malignant processes, planning cancer treatment is challenging. According to recent studies, natural products are likely to be effective in cancer prevention and treatment. Among bioactive flavonoids found in fruits and vegetables, kaempferol (KMP) is known for its anti-inflammatory, antioxidant, and anticancer properties. This systematic review aims to highlight the potential therapeutic effects of KMP on different types of solid malignant tumors. This review was conducted following the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines. Searches were performed in EMBASE, Medline/PubMed, Cochrane Collaboration Library, Science Direct, Scopus, and Google Scholar. After the application of study criteria, 64 studies were included. In vitro experiments demonstrated that KMP exerts antitumor effects by controlling tumor cell cycle progression, proliferation, apoptosis, migration, and invasion, as well as by inhibiting angiogenesis. KMP was also able to inhibit important markers that regulate epithelial-mesenchymal transition and enhanced the sensitivity of cancer cells to traditional drugs used in chemotherapy, including cisplatin and 5-fluorouracil. This flavonoid is a promising therapeutic compound and its combination with current anticancer agents, including targeted drugs, may potentially produce more effective and predictable results.

Significance of flavonoids targeting PI3K/Akt/HIF-1α signaling pathway in therapy-resistant cancer cells - A potential contribution to the predictive, preventive, and personalized medicine

BACKGROUND

Cancer management faces multiple obstacles, including resistance to current therapeutic approaches. In the face of challenging microenvironments, cancer cells adapt metabolically to maintain their supply of energy and precursor molecules for biosynthesis and thus sustain rapid proliferation and tumor growth. Among the various metabolic adaptations observed in cancer cells, the altered glucose metabolism is the most widely studied. The aberrant glycolytic modification in cancer cells has been associated with rapid cell division, tumor growth, cancer progression, and drug resistance. The higher rates of glycolysis in cancer cells, as a hallmark of cancer progression, is modulated by the transcription factor hypoxia inducible factor 1 alpha (HIF-1α), a downstream target of the PI3K/Akt signaling, the most deregulated pathway in cancer.

AIM OF REVIEW

We provide a detailed overview of current, primarily experimental, evidence on the potential effectiveness of flavonoids to combat aberrant glycolysis-induced resistance of cancer cells to conventional and targeted therapies. The manuscript focuses primarily on flavonoids reducing cancer resistance via affecting PI3K/Akt, HIF-1α (as the transcription factor critical for glucose metabolism of cancer cells that is regulated by PI3K/Akt pathway), and key glycolytic mediators downstream of PI3K/Akt/HIF-1α signaling (glucose transporters and key glycolytic enzymes).

KEY SCIENTIFIC CONCEPTS OF REVIEW

The working hypothesis of the manuscript proposes HIF-1α - the transcription factor critical for glucose metabolism of cancer cells regulated by PI3K/Akt pathway as an attractive target for application of flavonoids to mitigate cancer resistance. Phytochemicals represent a source of promising substances for cancer management applicable to primary, secondary, and tertiary care. However, accurate patient stratification and individualized patient profiling represent crucial steps in the paradigm shift from reactive to predictive, preventive, and personalized medicine (PPPM / 3PM). The article is focused on targeting molecular patterns by natural substances and provides evidence-based recommendations for the 3PM relevant implementation.

Natural products and mitochondrial allies in colorectal cancer therapy

Colorectal cancer (CRC) is a globally prevalent malignancy with a high potential for metastasis. Existing cancer treatments have limitations, including drug resistance and adverse effects. Researchers are striving to develop effective therapies to address these challenges. Impressively, contemporary research has discovered that many natural products derived from foods, plants, insects, and marine invertebrates can suppress the progression, metastasis, and invasion of CRC. In this review, we conducted a comprehensive search of the CNKI, PubMed, Embase, and Web of Science databases from inception to April 2023 to evaluate the efficacy of natural products targeting mitochondria to fight against CRC. Mitochondria are intracellular energy factories involved in cell differentiation, signal transduction, cell cycle regulation, apoptosis, and tumorigenesis. The identified natural products have been classified and summarized based on their mechanisms of action. These findings indicate that natural products can induce apoptosis in colorectal cancer cells by inhibiting the mitochondrial respiratory chain, ROS elevation, disruption of mitochondrial membrane potential, the release of pro-apoptotic factors, modulation of the Bcl-2 protein family to facilitate cytochrome c release, induction of apoptotic vesicle activity by activating the caspase protein family, and selective targeting of mitochondrial division. Furthermore, diverse apoptotic signaling pathways targeting mitochondria, such as the MAPK, p53, STAT3, JNK and AKT pathway, have been triggered by natural products. Natural products such as diosgenin, allopurinol, and clausenidin have demonstrated low toxicity, high efficacy, and multi-targeted properties. Mitochondria-targeting natural products have great potential for overcoming the challenges of CRC therapy.

Silver nanoparticles formulation of Marrubium alysson L. phenolic extract potentiates cytotoxicity through apoptosis with molecular docking study as Bcl-2 inhibitors

Crude or semi-purified extracts of plants can play a significant role as antitumor agents. They were used as stabilizing and reducing agents in the preparation of silver nanoparticles (AgNPs) that allows these particles to have more efficient cytotoxic activity. In the current study, the extract of Marrubium alysson L., a plant of common occurrence in Egypt was used to synthesize AgNPs for the first time, where comparison of anticancer activity of crude and phenolic extracts with the AgNPs were extensively studied against cancer cell lines PC-3 and HCT-116. Interestingly, AgNPs of the crude extract exhibited promising cytotoxicity with IC50 values of 10.4 and 16.3 μg/ml, while AgNPs of the phenolic extract exhibited very potent cytotoxicity with IC50 values of 2.66 and 1.34 μg/ml compared to Doxorubicin (as a standard reference drug) that exhibited IC50 values of 5.13 and 4.36 μg/ml, respectively against the tested cells. Additionally, AgNPs of the phenolic extract induced apoptosis in HCT-116 with a higher ratio than in PC-3 cells. It induced apoptosis in PC-3 cells by 79.3-fold change, while it induced total colon apoptotic cell death by 228.3-fold change compared to untreated control. Finally, the apoptotic activity of AgNPs of the phenolic extract in the treated PC-3 and HCT-116 cells was confirmed using RT-PCR. As a result, AgNPs of the phenolic extract could be considered a promising anticancer candidate through apoptosis-induction.Communicated by Ramaswamy H. Sarma.

Genomic-driven nutritional interventions for radiotherapy-resistant rectal cancer patient

Radiotherapy response of rectal cancer patients is dependent on a myriad of molecular mechanisms including response to stress, cell death, and cell metabolism. Modulation of lipid metabolism emerges as a unique strategy to improve radiotherapy outcomes due to its accessibility by bioactive molecules within foods. Even though a few radioresponse modulators have been identified using experimental techniques, trying to experimentally identify all potential modulators is intractable. Here we introduce a machine learning (ML) approach to interrogate the space of bioactive molecules within food for potential modulators of radiotherapy response and provide phytochemically-enriched recipes that encapsulate the benefits of discovered radiotherapy modulators. Potential radioresponse modulators were identified using a genomic-driven network ML approach, metric learning and domain knowledge. Then, recipes from the Recipe1M database were optimized to provide ingredient substitutions maximizing the number of predicted modulators whilst preserving the recipe's culinary attributes. This work provides a pipeline for the design of genomic-driven nutritional interventions to improve outcomes of rectal cancer patients undergoing radiotherapy.

Quercetin reverses 5-fluorouracil resistance in colon cancer cells by modulating the NRF2/HO-1 pathway

Quercetin (Que) has been proven to enhance the chemosensitivity of multiple cancers, including colon cancer (CC). However, whether the combination of Que and 5-fluorouracil (5-FU) has a synergistic effect on drug-resistant CC cells has not previously been reported. The effect of Que (5 and 10 μg/mL) on cell vitality and apoptosis of CC and CC drug-resistant cells was examined using a cell counting kit-8 (CCK-8) and flow cytometry. After cells were treated with 5-FU (10, 40 μg/mL), Que (10 μM, 40 μM), or 5-FU in combination with Que, cell proliferation, apoptosis, oxidative stress-related factors, reactive oxygen species (ROS), and nuclear factor erythroid 2-related factor (Nrf2)/heme oxygenase-1 (HO-1) pathway-related factors were examined by colony formation assay, flow cytometry, ELISA, ROS kit, immunofluorescence assay, and Western blot. The results showed that 5-FU reduced cell viability and induced apoptosis of CC as well as 5-FU-resistant CC cells. Que further restrained the proliferation, oxidative stress-related factors (SOD, CAT, GPx, and GR), ROS production, and induced apoptosis in CC cells and 5-FU-resistant CC cells induced by 5-FU. Moreover, the combination of Que and 5-FU attenuated the Nrf2/HO-1 pathway-related marker levels in CC cells and 5-FU-resistant CC cells. Therefore, our results suggest that Que reverses 5-FU resistance in CC cells via modulating the Nrf2/HO-1 pathway.

Can the phenolic compounds of Manuka honey chemosensitize colon cancer stem cells? A deep insight into the effect on chemoresistance and self-renewal

Manuka honey, which is rich in pinocembrin, quercetin, naringenin, salicylic, p-coumaric, ferulic, syringic and 3,4-dihydroxybenzoic acids, has been shown to have pleiotropic effects against colon cancer cells. In this study, potential chemosensitizing effects of Manuka honey against 5-Fluorouracil were investigated in colonspheres enriched with cancer stem cells (CSCs), which are responsible for chemoresistance. Results showed that 5-Fluorouracil increased when it was combined with Manuka honey by downregulating the gene expression of both ATP-binding cassette sub-family G member 2, an efflux pump and thymidylate synthase, the main target of 5-Fluorouracil which regulates the ex novo DNA synthesis. Manuka honey was associated with decreased self-renewal ability by CSCs, regulating expression of several genes in Wnt/β-catenin, Hedgehog and Notch pathways. This preliminary study opens new areas of research into the effects of natural compounds in combination with pharmaceuticals and, potentially, increase efficacy or reduce adverse effects.

Application of Polyphenols and Flavonoids in Oncological Therapy

The use of naturally derived drugs in anti-cancer therapies has grown exponentially in recent years. Among natural compounds, polyphenols have shown potential therapeutic applications in treatment due to their protective functions in plants, their use as food additives, and their excellent antioxidant properties, resulting in beneficial effects on human health. Building more efficient cancer therapies with fewer side effects on human health can be achieved by combining natural compounds with conventional drugs, which are typically more aggressive than natural chemicals with polyphenols. This article reviews a wide variety of studies where polyphenolic compounds can play a key role as anticancer drugs, alone or in combination with other drugs. Moreover, the future directions of applications of various polyphenols in cancer therapy are shown.

Effects and Mechanisms of Kaempferol in the Management of Cancers through Modulation of Inflammation and Signal Transduction Pathways

Cancer is the principal cause of death and its incidence is increasing continuously worldwide. Various treatment approaches are in practice to treat cancer, but these treatment strategies may be associated with severe side effects and also produce drug resistance. However, natural compounds have established their role in cancer management with minimal side effects. In this vista, kaempferol, a natural polyphenol, mainly found in vegetables and fruits, has been revealed to have many health-promoting effects. Besides its health-promoting potential, its anti-cancer potential has also been described in in vivo as well as in in vitro studies. The anti-cancer potential of kaempferol has been proven through modulation of cell signaling pathways in addition to the induction of apoptosis and cell cycle arrest in cancer cells. It leads to the activation of tumor suppressor genes, inhibition of angiogenesis, PI3K/AKT pathways, STAT3, transcription factor AP-1, Nrf2 and other cell signaling molecules. Poor bioavailability of this compound is one of the major limitations for its proper and effective disease management actions. Recently, some novel nanoparticle-based formulations have been used to overcome these limitations. The aim of this review is to provide a clear picture regarding the mechanism of action of kaempferol in different cancers through the modulation of cell signaling molecules. Besides this, strategies to improve the efficacy and synergistic effects of this compound have also been described. However, more studies are needed based on clinical trials to fully explore the therapeutic role of this compound, especially in cancer treatment.

Exploring the Remarkable Chemotherapeutic Potential of Polyphenolic Antioxidants in Battling Various Forms of Cancer

Plant-derived compounds, specifically antioxidants, have played an important role in scavenging the free radicals present under diseased conditions. The persistent generation of free radicals in the body leads to inflammation and can result in even more severe diseases such as cancer. Notably, the antioxidant potential of various plant-derived compounds prevents and deregulates the formation of radicals by initiating their decomposition. There is a vast literature demonstrating antioxidant compounds' anti-inflammatory, anti-diabetic, and anti-cancer potential. This review describes the molecular mechanism of various flavonoids, such as quercetin, kaempferol, naringenin, epicatechin, and epicatechin gallate, against different cancers. Additionally, the pharmaceutical application of these flavonoids against different cancers using nanotechnologies such as polymeric, lipid-based nanoparticles (solid-lipid and liquid-lipid), liposomes, and metallic nanocarriers is addressed. Finally, combination therapies in which these flavonoids are employed along with other anti-cancer agents are described, indicating the effective therapies for the management of various malignancies.

Screening out Biomarkers of Tetrastigma hemsleyanum for Anti-Cancer and Anti-Inflammatory Based on Spectrum-Effect Relationship Coupled with UPLC-Q-TOF-MS

Tetrastigma hemsleyanum Diels et Gilg. (T. hemsleyanum) is an economically and medicinally valuable species within the genus Tetrastigma. However, the material basis of its pharmacological action and the biomarkers associated with its anti-cancer and anti-inflammatory effects are still unclear. Additionally, the T. hemsleyanum industry cannot grow because there is a lack of a scientific, universal, and measurable quality control system. This study aimed to explore the chemical basis quality markers related to the anti-cancer and anti-inflammatory effects of T. hemsleyanum to establish an effective quality evaluation method. UPLC-Q-TOF-MSE fingerprint profiles of T. hemsleyanum from different origins were established. Pharmacodynamic studies used HepG2 and HuH-7 cells and LPS-induced RAW264.7 to evaluate the anti-tumor and anti-inflammatory effects of the active ingredients. The spectrum-effect relationships between UPLC fingerprints and anti-cancer and anti-inflammatory activities were evaluated using PCA and PLSR statistical methods. Moreover, docking analysis was performed to identify specific active biomarkers with molecular targets associated with cancer and inflammation. Chlorogenic acid, quinic acid, catechin, kaempferol 3-rutinoside, apigenin-8-C-glucoside, and linolenic acid were associated with anticancer activity, while chlorogenic acid, quercetin, quinic acid, kaempferol 3-rutinoside, rutinum, apigenin-8-C-glucoside, and linolenic acid were associated with anti-inflammatory activity. The spectrum-effect relationship of T. hemsleyanum was successfully established, and the biomarkers for anti-cancer and anti-inflammatory effects were preliminary confirmed. These findings provide a theoretical basis for the elucidation of the substance basis of T. hemsleyanum and lay the foundation for its rapid identification, quality control, industrial research, and utilization.

Current Understanding of Flavonoids in Cancer Therapy and Prevention

Cancer is a major cause of death worldwide, with multiple pathophysiological manifestations. In particular, genetic abnormalities, inflammation, bad eating habits, radiation exposure, work stress, and toxin consumption have been linked to cancer disease development and progression. Recently, natural bioactive chemicals known as polyphenols found in plants were shown to have anticancer capabilities, destroying altered or malignant cells without harming normal cells. Flavonoids have demonstrated antioxidant, antiviral, anticancer, and anti-inflammatory effects. Flavonoid type, bioavailability, and possible method of action determine these biological actions. These low-cost pharmaceutical components have significant biological activities and are beneficial for several chronic disorders, including cancer. Recent research has focused primarily on isolating, synthesizing, and studying the effects of flavonoids on human health. Here we have attempted to summarize our current knowledge of flavonoids, focusing on their mode of action to better understand their effects on cancer.

Interplay between Signaling Pathways and Tumor Microenvironment Components: A Paradoxical Role in Colorectal Cancer

The study of the tumor microenvironment (TME) has become an important part of colorectal cancer (CRC) research. Indeed, it is now accepted that the invasive character of a primary CRC is determined not only by the genotype of the tumor cells, but also by their interactions with the extracellular environment, which thereby orchestrates the development of the tumor. In fact, the TME cells are a double-edged sword as they play both pro- and anti-tumor roles. The interaction of the tumor-infiltrating cells (TIC) with the cancer cells induces the polarization of the TIC, exhibiting an antagonist phenotype. This polarization is controlled by a plethora of interconnected pro- and anti-oncogenic signaling pathways. The complexity of this interaction and the dual function of these different actors contribute to the failure of CRC control. Thus, a better understanding of such mechanisms is of great interest and provides new opportunities for the development of personalized and efficient therapies for CRC. In this review, we summarize the signaling pathways linked to CRC and their implication in the development or inhibition of the tumor initiation and progression. In the second part, we enlist the major components of the TME and discuss the complexity of their cells functions.

Role of Plant-Derived Flavonoids in Cancer Treatment

Flavonoids are polyphenolic phytochemicals, which occur naturally in plants and possess both anti-oxidant and pro-oxidant properties. Flavonoids are gaining increasing popularity in the pharmaceutical industry as healthy and cost-effective compounds. Flavonoids show beneficial pharmacological activities in the treatment and prevention of various types of diseases. They are natural and less toxic agents for cancer chemotherapy and radiotherapy via regulation of multiple cell signaling pathways and pro-oxidant effects. In this review, we have summarized the mechanisms of action of selected flavonoids, and their pharmacological implications and potential therapeutic applications in cancer therapy.

Clitocybe nebularis extract and 5‑fluorouracil synergistically inhibit the growth of HT-29 colorectal cancer cells by inducing the S phase arrest

Although 5-fluorouracil (5-FU) is an important anticancer agent for the treatment of colorectal cancer, drug resistance, and dose-related side effects limit the effectiveness of the treatment. Therefore, developing new pharmaceuticals with effective and low toxicity is critically necessary for cancer therapy. This study aimed to investigate the cytotoxic activity of the Clitocybe nebularis mushroom extract (CN) on HT-29 human colon cancer cells. A series of in vitro experiments were performed on the HT-29, Caco-2, and HEK-293 cells, which includes cytotoxicity, drug interaction, colony formation, cell cycle, and migration assays. In addition, qRT-PCR experiment was also performed to investigate the potential molecular mechanisms of action of CN on the proliferation of colon cancer cell line. Our results show that CN exhibited selective cytotoxic activity on HT-29 and Caco-2 colon cancer cells, whereas no cytotoxic effect was observed on normal HEK-293 cells. With the combination of CN and 5‑FU, their cytotoxic activity on HT-29 cells was significantly increased compared to their use alone. In addition, the combination of CN and 5-FU also showed synergistic anticancer activity through cell cycle arrest in the S phase. The results also show that p21, p27, and p53 expression levels increased as a result of CN treatment. Our in vitro findings show that CN has a synergistic effect with 5-FU by inhibiting cell proliferation of colon cancer cells and inducing cell cycle arrest in the S phase.

Therapeutic Importance of Kaempferol in the Treatment of Cancer through the Modulation of Cell Signalling Pathways

Plant-derived flavonoids are considered natural nontoxic chemo-preventers and have been widely studied for cancer treatment in recent decades. Mostly all flavonoid compounds show significant anti-inflammatory, anticancer and antioxidant properties. Kaempferol (Kmp) is a well-studied compound and exhibits remarkable anticancer and antioxidant potential. Kmp can regulate various cancer-related processes and activities such as cell cycle, oxidative stress, apoptosis, proliferation, metastasis, and angiogenesis. The anti-cancer properties of Kmp primarily occur via modulation of apoptosis, MAPK/ERK1/2, P13K/Akt/mTOR, vascular endothelial growth factor (VEGF) signalling pathways. The anti-cancer property of Kmp has been recognized in several in-vivo and in-vitro studies which also includes numerous cell lines and animal models. This flavonoid possesses toxic activities against only cancer cells and have restricted toxicity on healthy cells. In this review, we present extensive research investigations about the therapeutic potential of Kmp in the management of different types of cancers. The anti-cancer properties of Kmp are discussed by concentration on its capability to target molecular-signalling pathway such as VEGF, STAT, p53, NF-κB and PI3K-AKT signalling pathways. The anti-cancer property of Kmf has gained a lot of attention, but the accurate action mechanism remains unclear. However, this natural compound has a great pharmacological capability and is now considered to be an alternative cancer treatment.

Exploiting Polyphenol-Mediated Redox Reorientation in Cancer Therapy

Polyphenol, one of the major components that exert the therapeutic effect of Chinese herbal medicine (CHM), comprises several categories, including flavonoids, phenolic acids, lignans and stilbenes, and has long been studied in oncology due to its significant efficacy against cancers in vitro and in vivo. Recent evidence has linked this antitumor activity to the role of polyphenols in the modulation of redox homeostasis (e.g., pro/antioxidative effect) in cancer cells. Dysregulation of redox homeostasis could lead to the overproduction of reactive oxygen species (ROS), resulting in oxidative stress, which is essential for many aspects of tumors, such as tumorigenesis, progression, and drug resistance. Thus, investigating the ROS-mediated anticancer properties of polyphenols is beneficial for the discovery and development of novel pharmacologic agents. In this review, we summarized these extensively studied polyphenols and discussed the regulatory mechanisms related to the modulation of redox homeostasis that are involved in their antitumor property. In addition, we discussed novel technologies and strategies that could promote the development of CHM-derived polyphenols to improve their versatile anticancer properties, including the development of novel delivery systems, chemical modification, and combination with other agents.

Flavonoids' Dual Benefits in Gastrointestinal Cancer and Diabetes: A Potential Treatment on the Horizon?

Diabetes and gastrointestinal cancers (GI) are global health conditions with a massive burden on patients' lives worldwide. The development of both conditions is influenced by several factors, such as diet, genetics, environment, and infection, which shows a potential link between them. Flavonoids are naturally occurring phenolic compounds present in fruits and vegetables. Once ingested, unabsorbed flavonoids reaching the colon undergo enzymatic modification by the gut microbiome to facilitate absorption and produce ring fission products. The metabolized flavonoids exert antidiabetic and anti-GI cancer properties, targeting major impaired pathways such as apoptosis and cellular proliferation in both conditions, suggesting the potentially dual effects of flavonoids on diabetes and GI cancers. This review summarizes the current knowledge on the impact of flavonoids on diabetes and GI cancers in four significant pathways. It also addresses the synergistic effects of selected flavonoids on both conditions. While this is an intriguing approach, more studies are required to better understand the mechanism of how flavonoids can influence the same impaired pathways with different outcomes depending on the disease.

Anti-cancer properties of cannflavin A and potential synergistic effects with gemcitabine, cisplatin, and cannabinoids in bladder cancer

Introduction

Several studies have shown anti-tumor effects of components present in cannabis in different models. Unfortunately, little is known about the potential anti-tumoral effects of most compounds present in cannabis in bladder cancer and how these compounds could potentially positively or negatively impact the actions of chemotherapeutic agents. Our study aims to evaluate the effects of a compound found in Cannabis sativa that has not been extensively studied to date, cannflavin A, in bladder cancer cell lines. We aimed to identify whether cannflavin A co-treatment with agents commonly used to treat bladder cancer, such as gemcitabine and cisplatin, is able to produce synergistic effects. We also evaluated whether co-treatment of cannflavin A with various cannabinoids could produce synergistic effects.

Methods

Two transitional cell carcinoma cell lines were used to assess the cytotoxic effects of the flavonoid cannflavin A up to 100 μM. We tested the potential synergistic cytotoxic effects of cannflavin A with gemcitabine (up to 100 nM), cisplatin (up to 100 μM), and cannabinoids (up to 10 μM). We also evaluated the activation of the apoptotic cascade using annexin V and whether cannflavin A has the ability to reduce invasion using a Matrigel assay.

Results

Cell viability of bladder cancer cell lines was affected in a concentration-dependent fashion in response to cannflavin A, and its combination with gemcitabine or cisplatin induced differential responses—from antagonistic to additive—and synergism was also observed in some instances, depending on the concentrations and drugs used. Cannflavin A also activated apoptosis via caspase 3 cleavage and was able to reduce invasion by 50%. Interestingly, cannflavin A displayed synergistic properties with other cannabinoids like Δ⁹-tetrahydrocannabinol, cannabidiol, cannabichromene, and cannabivarin in the bladder cancer cell lines.

Discussion

Our results indicate that compounds from Cannabis sativa other than cannabinoids, like the flavonoid cannflavin A, can be cytotoxic to human bladder transitional carcinoma cells and that this compound can exert synergistic effects when combined with other agents. In vivo studies will be needed to confirm the activity of cannflavin A as a potential agent for bladder cancer treatment.

Supplementary Information

The online version contains supplementary material available at 10.1186/s42238-022-00151-y.

Gnetum montanum extract induces apoptosis by inhibiting the activation of AKT in SW480 human colon cancer cells

CONTEXT

Gnetum montanum Markgr. (Gnetaceae) is used to treat rheumatic arthralgia and bruises in the clinic.

OBJECTIVE

To exam the activity and mechanism of G. montanum extract (GME) against colon cancer cells SW480.

MATERIALS AND METHODS

The anti-proliferative activity of GME (0-120 μg/mL) on SW480 cells was determined using MTS assay at 24, 48, and 72 h. The in vitro activity of GME (0-120 μg/mL) on SW480 cells was investigated using flow cytometry and western blotting analysis. The in vivo activity of GME was evaluated using xenograft tumour model of zebrafish and nude mice. The chemical composition of GME was detected by using HPLC-MS/MS.

RESULTS

The IC₅₀ value SW480 cells viability by GME were 126.50, 78.25, and 50.77 μg/mL, respectively, for 24, 48, and 72 h. The experiments showed that apoptotic cells and G2/M phase cells increased from 20.81 to 61.53% (p < 0.01) and 25.76 to 34.93% with 120 μg/mL GME, respectively. GME also down-regulated the protein expression of P-AKT, P-GSK-3β, P-PDK1, P-c-Raf, caspase-3, and Bcl-2, and up-regulated the expression cleaved caspase-3, cleaved PARP, and Bax. In vivo study found that GME can significantly inhibit the growth and migration of SW480 cells in xenograft zebrafish. GME reduced the nude mice tumour weight to approximately 32.19% at 28 mg/kg/day and to 53.17% (p < 0.01) at 56 mg/kg/day. Forty-two compounds were identified from the GME.

DISCUSSION AND CONCLUSIONS

GME has a significant antitumor effect on colon cancer cells SW480, and it has the potential to be developed as an anticancer agent.

Dihydropyrimidine Dehydrogenase-Mediated Resistance to 5-Fluorouracil: Mechanistic Investigation and Solution

5-Fluorouracil (5-FU) is one of the most widely used chemotherapeutics for the treatment of cancers associated with the aerodigestive tract, breast, and colorectal system. The efficacy of 5-FU is majorly affected by dihydropyrimidine dehydrogenase (DPD) as it degrades more than 80% of administered 5-FU into an inactive metabolite, dihydrofluorouracil. Herein we discuss the molecular mechanism of this inactivation by analyzing the interaction pattern and electrostatic complementarity of the DPD-5-FU complex. The basis of DPD overexpression in cancer cell lines due to significantly distinct levels of the miRNAs (miR-134, miR-27b, and miR-27a) compared to normal cells has also been outlined. Additionally, some kinases including sphingosine kinase 2 (SphK2) have been reported to correlate with DPD expression. Currently, to address this problem various strategies are reported in the literature, including 5-FU analogues (bypass the DPD-mediated inactivation), DPD downregulators (regulate the DPD expression levels in tumors), inhibitors (as promising adjuvants), and formulation development loaded with 5-FU (liposomes, nanoparticles, nanogels, etc.), which are briefly discussed in this Review.

Kaempferol: A potential agent in the prevention of colorectal cancer

Colorectal cancer (CRC) is the third most prevalent cancer in relation to incidence and mortality rate and its incidence is considerably increasing annually due to the change in the dietary habit and lifestyle of the world population. Although conventional therapeutic options, such as surgery, chemo- and radiotherapy have profound impacts on the treatment of CRC, dietary therapeutic agents, particularly natural products have been regarded as the safest alternatives for the treatment of CRC. Kaempferol (KMP), a naturally derived flavonol, has been shown to reduce the production of reactive oxygen species (ROS), such as superoxide ions, hydroxyl radicals, and reactive nitrogen species (RNS), especially peroxynitrite. Furthermore, this flavonol inhibits xanthine oxidase (XO) activity and increases the activities of catalase, heme oxygenase-1 (HO), and superoxide dismutase (SOD) in a wide range of cancer and non-cancer cells. Based on several studies, KMP is also a hopeful anticancer which carries out its anticancer action via suppression of angiogenesis, stimulation of apoptosis, and cell cycle arrest. Due to various applications of KMP as an anticancer flavonol, this review article aims to highlight the current knowledge regarding the role of KMP in CRC.

Wenzi Jiedu Recipe ameliorates colorectal cancer by remodeling the gut microbiota and tumor microenvironment

Introduction

Wenzi Jiedu Recipe (WJR), traditional Chinese medicine (TCM) formula, has been proven to be clinically useful in the treatment of colorectal cancer (CRC). However, its underlying mechanisms are still elusive, which limits its wider application. Thus, we aimed to evaluate the effect of WJR on CRC and elucidate mechanisms underlying its action.

Methods

Network pharmacology was employed to clarify the “herb-active ingredient-target” network of WJR. The 16S rDNA sequencing method was used to analyze the changes of gut microbes mediated by WJR in tumor-bearing mice with CRC. The proportions of CD4+ T cell and CD8+ T cell were measured by flow cytometry. Levels of the cytokines interleukin (IL)-10, interferon (IFN)-γ, and tumor necrosis factor (TNF)-α were assessed by immunohistochemistry and enzyme-linked immunosorbent assay (ELISA).

Results

WJR showed significant anti-CRC effects both in vitro and in vivo. Network pharmacology revealed that WJR exerts anti-CRC therapeutic effect on multiple targets and signaling pathways. Gut microbiota analysis revealed that WJR therapy significantly enriched for Oscillibacter and Bacteroides_acidifacien. In particular, we found that WJR significantly increased the proportion of CD8+ T cells and the expression of immune-associated cytokines IL-10, IFN-γ, and TNF-α.

Conclusion

The regulation of gut microbiota by WJR may be the breakthrough point to clarify its mechanism of action in the treatment of CRC, and it has a good prospect of clinical application.

Advances in Dietary Phenolic Compounds to Improve Chemosensitivity of Anticancer Drugs

Simple Summary

Several dietary phenolic compounds isolated from medicinal plants exert significant anticancer effects via several mechanisms. They induce apoptosis, autophagy, telomerase inhibition, and angiogenesis. Certain dietary phenolic compounds increase the effectiveness of drugs used in conventional chemotherapy. Some clinical uses of dietary phenolic compounds for treating certain cancers have shown remarkable therapeutic results, suggesting effective incorporation in anticancer treatments in combination with traditional chemotherapeutic agents.

Abstract

Despite the significant advances and mechanistic understanding of tumor processes, therapeutic agents against different types of cancer still have a high rate of recurrence associated with the development of resistance by tumor cells. This chemoresistance involves several mechanisms, including the programming of glucose metabolism, mitochondrial damage, and lysosome dysfunction. However, combining several anticancer agents can decrease resistance and increase therapeutic efficacy. Furthermore, this treatment can improve the effectiveness of chemotherapy. This work focuses on the recent advances in using natural bioactive molecules derived from phenolic compounds isolated from medicinal plants to sensitize cancer cells towards chemotherapeutic agents and their application in combination with conventional anticancer drugs. Dietary phenolic compounds such as resveratrol, gallic acid, caffeic acid, rosmarinic acid, sinapic acid, and curcumin exhibit remarkable anticancer activities through sub-cellular, cellular, and molecular mechanisms. These compounds have recently revealed their capacity to increase the sensitivity of different human cancers to the used chemotherapeutic drugs. Moreover, they can increase the effectiveness and improve the therapeutic index of some used chemotherapeutic agents. The involved mechanisms are complex and stochastic, and involve different signaling pathways in cancer checkpoints, including reactive oxygen species signaling pathways in mitochondria, autophagy-related pathways, proteasome oncogene degradation, and epigenetic perturbations.

Inhibition and potential treatment of colorectal cancer by natural compounds via various signaling pathways

Colorectal cancer (CRC) is a common type of malignant digestive tract tumor with a high incidence rate worldwide. Currently, the clinical treatment of CRC predominantly include surgical resection, postoperative chemotherapy, and radiotherapy. However, these treatments contain severe limitations such as drug side effects, the risk of recurrence and drug resistance. Some natural compounds found in plants, fungi, marine animals, and bacteria have been shown to inhibit the occurrence and development of CRC. Although the explicit molecular mechanisms underlying the therapeutic effects of these compounds on CRC are not clear, classical signaling transduction pathways such as NF-kB and Wnt/β-catenin are extensively regulated. In this review, we have summarized the specific mechanisms regulating the inhibition and development of CRC by various types of natural compounds through nine signaling pathways, and explored the potential therapeutic values of these natural compounds in the clinical treatment of CRC.

Long-term resistance to 5-fluorouracil promotes epithelial-mesenchymal transition, apoptosis evasion, autophagy, and reduced proliferation rate in colon cancer cells

The drug, 5-fluorouracil (5FU) is a standard first-line treatment for colorectal cancer (CRC) patients. However, drug resistance acquisition remains an important challenge for effective clinical outcomes. Here, we established a long-term drug-resistant CRC model and explored the cellular events underlying 5FU resistance. We showed that 5FU-treated cells (HCT-116 5FUR) using a prolonged treatment protocol were significantly more resistant than parental cells. Likewise, cell viability and IC50 values were also observed to increase in HCT-116 5FUR cells when treated with increasing doses of oxaliplatin, indicating a cross-resistance mechanism to other cytotoxic agents. Moreover, HCT-116 5FUR cells exhibited metabolic and molecular changes, as evidenced by increased thymidylate synthase levels and upregulated mRNA levels of ABCB1. HCT-116 5FUR cells were able to overcome S phase arrest and evade apoptosis, as well as activate autophagy, as indicated by increased LC3B levels. Cells treated with low and high doses displayed epithelial-mesenchymal transition (EMT) features, as observed by decreased E-cadherin and claudin-3 levels, increased vimentin protein levels, and increased SLUG, ZEB2 and TWIST1 mRNA levels. Furthermore, HCT-116 5FUR cells displayed enhanced migration and invasion capabilities. Interestingly, we found that the 5FU drug-resistance gene signature is positively associated with the mesenchymal signature in CRC samples, and that ABCB1 and ZEB2 co-expressed at high levels could predict poor outcomes in CRC patients. Overall, the 5FU long-term drug-resistance model established here induced various cellular events, and highlighted the importance of further efforts to identify promising targets involved in more than one cellular event to successfully overcome drug-resistance.

A renewed concept on the MAPK signaling pathway in cancers: Polyphenols as a choice of therapeutics

Abnormalities in the mitogen-activated protein kinase (MAPK) signaling pathway are a key contributor to the carcinogenesis process and have therefore been implicated in several aspects of tumorigenesis, including cell differentiation, proliferation, invasion, angiogenesis, apoptosis, and metastasis. This pathway offers multiple molecular targets that may be modulated for anticancer activity and is of great interest for several malignancies. Polyphenols from various dietary sources have been observed to interfere with certain aspects of this pathway and consequently play a substantial role in the development and progression of cancer by suppressing cell growth, inactivating carcinogens, blocking angiogenesis, causing cell death, and changing immunity. A good number of polyphenolic compounds have shown promising outcomes in numerous pieces of research and are currently being investigated clinically to treat cancer patients. The current study concentrates on the role of the MAPK pathway in the development and metastasis of cancer, with particular emphasis on dietary polyphenolic compounds that influence the different MAPK sub-pathways to obtain an anticancer effect. This study aims to convey an overview of the various aspects of the MAPK pathway in cancer development and invasion, as well as a review of the advances achieved in the development of polyphenols to modulate the MAPK signaling pathway for better treatment of cancer.

Contribution of the diverse experimental models to unravelling the biological scope of dietary (poly)phenols

The health benefits associated with (poly)phenols need to be supported by robust and insightful information on their biological effects. The use of in vitro, ex vivo, and in vivo models is crucial to demonstrate functionalities in specific targets. In this regard, bioaccessibility, bioavailability, and tissue/organ distribution need to be fully understood and established. In addition, the structure-function relationships, concerning both descriptive and mechanistic information, between specific compounds and therapeutic objectives, need to be supported by results obtained from in vivo studies. Nevertheless, these studies are not always possible or have some limitations, particularly concerning the mechanistic information explaining the health benefits provided that should be covered with complementary experimental models. Based on these premises, this review aims to overview the contribution of the separate experimental approaches to gain insights into the bioaccessibility, bioavailability, and bioactivity of (poly)phenols. To achieve this objective, recent evidence available on the linkage of healthy/functional foods with the incidence of non-communicable pathologies is presented. The different experimental approaches provide complementary information that allows advances to be applied to the knowledge gained on the functional properties and mechanistic facts responsible for the health attributions of polyphenols. © 2022 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

The Role of Natural Products and Their Multitargeted Approach to Treat Solid Cancer

Natural products play a critical role in the discovery and development of numerous drugs for the treatment of various types of cancer. These phytochemicals have demonstrated anti-carcinogenic properties by interfering with the initiation, development, and progression of cancer through altering various mechanisms such as cellular proliferation, differentiation, apoptosis, angiogenesis, and metastasis. Treating multifactorial diseases, such as cancer with agents targeting a single target, might lead to limited success and, in many cases, unsatisfactory outcomes. Various epidemiological studies have shown that the steady consumption of fruits and vegetables is intensely associated with a reduced risk of cancer. Since ancient period, plants, herbs, and other natural products have been used as healing agents. Likewise, most of the medicinal ingredients accessible today are originated from the natural resources. Regardless of achievements, developing bioactive compounds and drugs from natural products has remained challenging, in part because of the problem associated with large-scale sequestration and mechanistic understanding. With significant progress in the landscape of cancer therapy and the rising use of cutting-edge technologies, we may have come to a crossroads to review approaches to identify the potential natural products and investigate their therapeutic efficacy. In the present review, we summarize the recent developments in natural products-based cancer research and its application in generating novel systemic strategies with a focus on underlying molecular mechanisms in solid cancer.

Kaempferol: A flavonoid with wider biological activities and its applications

Kaempferol and its derivatives are naturally occurring phytochemicals with promising bioactivities. This flavonol can reduce the lipid oxidation in the human body, prevent the organs and cell structure from deterioration and protect their functional integrity. This review has extensively highlighted the antioxidant, antimicrobial, anticancer, neuroprotective, and hepatoprotective activity of kaempferol. However, poor water solubility and low bioavailability of kaempferol greatly limit its applications. The utilization of advanced delivery systems can improve its stability, efficacy, and bioavailability. This is the first review that aimed to comprehensively collate some of the vital information published on biosynthesis, mechanism of action, bioactivities, bioavailability, and toxicological potential of kaempferol. Besides, it provides insights into the future direction on the improvement of bioavailability of kaempferol for wide applications.

Molecular Pathways Involved in the Anti-Cancer Activity of Flavonols: A Focus on Myricetin and Kaempferol

Natural compounds have always represented valuable allies in the battle against several illnesses, particularly cancer. In this field, flavonoids are known to modulate a wide panel of mechanisms involved in tumorigenesis, thus rendering them worthy candidates for both cancer prevention and treatment. In particular, it was reported that flavonoids regulate apoptosis, as well as hamper migration and proliferation, crucial events for the progression of cancer. In this review, we collect recent evidence concerning the anti-cancer properties of the flavonols myricetin and kaempferol, discussing their mechanisms of action to give a thorough overview of their noteworthy capabilities, which are comparable to those of their most famous analogue, namely quercetin. On the whole, these flavonols possess great potential, and hence further study is highly advised to allow a proper definition of their pharmaco-toxicological profile and assess their potential use in protocols of chemoprevention and adjuvant therapies.

Evidence for Anticancer Effects of Chinese Medicine Monomers on Colorectal Cancer

Colorectal cancer is one of the most commonly occurring cancers worldwide. Although clinical reports have indicated the anticancer effects of Chinese herbal medicine, the multiple underlying molecular and biochemical mechanisms of action remain to be fully characterized. Chinese medicine (CM) monomers, which are the active components of CM, serve as the material basis of the functional mechanisms of CM. The aim of this review is to summarize the current experimental evidence from in vitro, in vivo, and clinical studies for the effects of CM monomers in colorectal cancer prevention and treatment, providing some useful references for future research.

Cancer Chemotherapy via Natural Bioactive Compounds

BACKGROUND

Cancer-induced mortality is increasingly prevalent globally which skyrocketed the necessity to discover new/novel safe and effective anticancer drugs. Cancer is characterized by the continuous multiplication of cells in the human which is unable to control. Scientific research is drawing its attention towards naturally-derived bioactive compounds as they have fewer side effects compared to the current synthetic drugs used for chemotherapy.

OBJECTIVE

Drugs isolated from natural sources and their role in the manipulation of epigenetic markers in cancer are discussed briefly in this review article.

METHODS

With advancing medicinal plant biotechnology and microbiology in the past century, several anticancer phytomedicines were developed. Modern pharmacopeia contains at least 25% herbal-based remedy including clinically used anticancer drugs. These drugs mainly include the podophyllotoxin derivatives vinca alkaloids, curcumin, mistletoe plant extracts, taxanes, camptothecin, combretastatin, and others including colchicine, artesunate, homoharringtonine, ellipticine, roscovitine, maytanasin, tapsigargin,andbruceantin.

RESULTS

Compounds (psammaplin, didemnin, dolastin, ecteinascidin,and halichondrin) isolated from marine sources and animals such as microalgae, cyanobacteria, heterotrophic bacteria, invertebrates. They have been evaluated for their anticancer activity on cells and experimental animal models and used chemotherapy.Drug induced manipulation of epigenetic markers plays an important role in the treatment of cancer.

CONCLUSION

The development of a new drug from isolated bioactive compounds of plant sources has been a feasible way to lower the toxicity and increase their effectiveness against cancer. Potential anticancer therapeutic leads obtained from various ethnomedicinal plants, foods, marine, and microorganisms are showing effective yet realistically safe pharmacological activity. This review will highlight important plant-based bioactive compounds like curcumin, stilbenes, terpenes, other polyphenolic phyto-compounds, and structurally related families that are used to prevent/ ameliorate cancer. However, a contribution from all possible fields of science is still a prerequisite for discovering safe and effective anticancer drugs.

Kaempferol Can Reverse the 5-Fu Resistance of Colorectal Cancer Cells by Inhibiting PKM2-Mediated Glycolysis

Resistance to 5-Fluorouracil (5-Fu) chemotherapy is the main cause of treatment failure in the cure of colon cancer. Therefore, there is an urgent need to explore a safe and effective multidrug resistance reversal agent for colorectal cancer, which would be of great significance for improving clinical efficacy. The dietary flavonoid kaempferol plays a key role in the progression of colorectal cancer and 5-Fu resistance. However, the molecular mechanism of kaempferol in reversing 5-Fu resistance in human colorectal cancer cells is still unclear. We found that kaempferol could reverse the drug resistance of HCT8-R cells to 5-Fu, suggesting that kaempferol alone or in combination with 5-Fu has the potential to treat colorectal cancer. It is well known that aerobic glycolysis is related to tumor growth and chemotherapy resistance. Indeed, kaempferol treatment significantly reduced glucose uptake and lactic acid production in drug-resistant colorectal cancer cells. In terms of mechanism, kaempferol promotes the expression of microRNA-326 (miR-326) in colon cancer cells, and miR-326 could inhibit the process of glycolysis by directly targeting pyruvate kinase M2 isoform (PKM2) 3'-UTR (untranslated region) to inhibit the expression of PKM2 or indirectly block the alternative splicing factors of PKM mRNA, and then reverse the resistance of colorectal cancer cells to 5-Fu. Taken together, our data suggest that kaempferol may play an important role in overcoming resistance to 5-Fu therapy by regulating the miR-326-hnRNPA1/A2/PTBP1-PKM2 axis.

The Anti-Cancer Effects of Red-Pigmented Foods: Biomarker Modulation and Mechanisms Underlying Cancer Progression

Cancer is one the most malignant diseases that is a leading cause of death worldwide. Vegetables and fruits contain beneficial nutrients such as vitamins, minerals, folates, dietary fibers, and various natural bioactive compounds. These can prevent the pathological processes of many cancers and reduce cancer related mortality. Specifically, the anti-cancer effect of vegetables and fruits is largely attributable to the natural bioactive compounds present within them. A lot of bioactive compounds have very specific colors with pigments and the action of them in the human body varies by their color. Red-pigmented foods, such as apples, oranges, tomatoes, cherries, grapes, berries, and red wine, have been widely reported to elicit beneficial effects and have been investigated for their anti-tumor, anti-inflammatory, and antioxidative properties, as well as anti-cancer effect. Most of the anti-cancer effects of bioactive compounds in red-pigmented foods arise from the suppression of cancer cell invasion and metastasis, as well as the induction of apoptosis and cell cycle arrest. In this review, we assessed publications from the last 10 years and identified 10 bioactive compounds commonly studied in red-pigmented foods: lycopene, anthocyanin, β-carotene, pectin, betaine, rutin, ursolic acid, kaempferol, quercetin, and myricetin. We focused on the mechanisms and targets underlying the anti-cancer effect of the compounds and provided rationale for further investigation of the compounds to develop more potent anti-cancer treatment methods.

Cancer Chemoprevention: A Strategic Approach Using Phytochemicals

Cancer chemoprevention approaches are aimed at preventing, delaying, or suppressing tumor incidence using synthetic or natural bioactive agents. Mechanistically, chemopreventive agents also aid in mitigating cancer development, either by impeding DNA damage or by blocking the division of premalignant cells with DNA damage. Several pre-clinical studies have substantiated the benefits of using various dietary components as chemopreventives in cancer therapy. The incessant rise in the number of cancer cases globally is an issue of major concern. The excessive toxicity and chemoresistance associated with conventional chemotherapies decrease the success rates of the existent chemotherapeutic regimen, which warrants the need for an efficient and safer alternative therapeutic approach. In this scenario, chemopreventive agents have been proven to be successful in protecting the high-risk populations from cancer, which further validates chemoprevention strategy as rational and promising. Clinical studies have shown the effectiveness of this approach in managing cancers of different origins. Phytochemicals, which constitute an appreciable proportion of currently used chemotherapeutic drugs, have been tested for their chemopreventive efficacy. This review primarily aims to highlight the efficacy of phytochemicals, currently being investigated globally as chemopreventives. The clinical relevance of chemoprevention, with special emphasis on the phytochemicals, curcumin, resveratrol, tryptanthrin, kaempferol, gingerol, emodin, quercetin genistein and epigallocatechingallate, which are potential candidates due to their ability to regulate multiple survival pathways without inducing toxicity, forms the crux of this review. The majority of these phytochemicals are polyphenols and flavanoids. We have analyzed how the key molecular targets of these chemopreventives potentially counteract the key drivers of chemoresistance, causing minimum toxicity to the body. An overview of the underlying mechanism of action of these phytochemicals in regulating the key players of cancer progression and tumor suppression is discussed in this review. A summary of the clinical trials on the important phytochemicals that emerge as chemopreventives is also incorporated. We elaborate on the pre-clinical and clinical observations, pharmacokinetics, mechanism of action, and molecular targets of some of these natural products. To summarize, the scope of this review comprises of the current status, limitations, and future directions of cancer chemoprevention, emphasizing the potency of phytochemicals as effective chemopreventives.

Purshia plicata Triggers and Regulates Proteins Related to Apoptosis in HeLa Cancer Cells

Cervical cancer represents a public health problem, develops resistance to traditional therapies and cost-of-treatment is high. These disadvantages have led to the search for alternative bioactive-compound-based therapies. Said bioactive compounds include phenolic compounds, flavonoids, and tannins. The present study aimed to evaluate the therapeutic effect of a P. plicata extract on the HeLa cell line. Viability and apoptosis assays were run on the two cell lines treated with the extract. The peptides, up- and down-expressed in both cell lines, were identified by PDQuest analysis software and high-performance liquid chromatography/mass spectrometry/mass spectrometry (HPLC/MS/MS). Our results show that a 500 mg/L treatment deregulated cell viability, with different apoptotic morphologies observed which are associated with the presence of bio-compounds, which up- and down-regulated the peptides. In conclusion, P. plicata regulates proteins associated with apoptosis in HeLa cancer cells.