The Multifaceted Role of Flavonoids in Cancer Therapy: Leveraging Autophagy with a Double-Edged Sword

Natural compounds-based nanomedicines for cancer treatment: Future directions and challenges

Several efforts have been extensively accomplished for the amelioration of the cancer treatments using different types of new drugs and less invasives therapies in comparison with the traditional therapeutic modalities, which are widely associated with numerous drawbacks, such as drug resistance, non-selectivity and high costs, restraining their clinical response. The application of natural compounds for the prevention and treatment of different cancer cells has attracted significant attention from the pharmaceuticals and scientific communities over the past decades. Although the use of nanotechnology in cancer therapy is still in the preliminary stages, the application of nanotherapeutics has demonstrated to decrease the various limitations related to the use of natural compounds, such as physical/chemical instability, poor aqueous solubility, and low bioavailability. Despite the nanotechnology has emerged as a promise to improve the bioavailability of the natural compounds, there are still limited clinical trials performed for their application with various challenges required for the pre-clinical and clinical trials, such as production at an industrial level, assurance of nanotherapeutics long-term stability, physiological barriers and safety and regulatory issues. This review highlights the most recent advances in the nanocarriers for natural compounds secreted from plants, bacteria, fungi, and marine organisms, as well as their role on cell signaling pathways for anticancer treatments. Additionally, the clinical status and the main challenges regarding the natural compounds loaded in nanocarriers for clinical applications were also discussed.

Generation of Hydrogen Peroxide in Cancer Cells: Advancing Therapeutic Approaches for Cancer Treatment

Cancer cells show altered antioxidant defense systems, dysregulated redox signaling, and increased generation of reactive oxygen species (ROS). Targeting cancer cells through ROS-mediated mechanisms has emerged as a significant therapeutic strategy due to its implications in cancer progression, survival, and resistance. Extensive research has focused on selective generation of H2O2 in cancer cells for selective cancer cell killing by employing various strategies such as metal-based prodrugs, photodynamic therapy, enzyme-based systems, nano-particle mediated approaches, chemical modulators, and combination therapies. Many of these H2O2-amplifying approaches have demonstrated promising anticancer effects and selectivity in preclinical investigations. They selectively induce cytotoxicity in cancer cells while sparing normal cells, sensitize resistant cells, and modulate the tumor microenvironment. However, challenges remain in achieving selectivity, addressing tumor heterogeneity, ensuring efficient delivery, and managing safety and toxicity. To address those issues, H2O2-generating agents have been combined with other treatments leading to optimized combination therapies. This review focuses on various chemical agents/approaches that kill cancer cells via H2O2-mediated mechanisms. Different categories of compounds that selectively generate H2O2 in cancer cells are summarized, their underlying mechanisms and function are elucidated, preclinical and clinical studies as well as recent advancements are discussed, and their prospects as targeted therapeutic agents and their therapeutic utility in combination with other treatments are explored. By understanding the potential of these compounds, researchers can pave the way for the development of effective and personalized cancer treatments.

Unveiling the power of flavonoids: A dynamic exploration of their impact on cancer through matrix metalloproteinases regulation

Cancer stands as a significant contributor to global mortality rates, primarily driven by its progression and widespread dissemination. Despite notable strides in cancer therapy, the efficacy of current treatment strategies is compromised due to their inherent toxicity and the emergence of chemoresistance. Consequently, there is a critical need to evaluate alternative therapeutic approaches, with natural compounds emerging as promising candidates, showcasing demonstrated anticancer capabilities in various research models. This review manuscript presents a comprehensive examination of the regulatory mechanisms governing the expression of matrix metalloproteinases (MMPs) and delves into the potential therapeutic role of flavonoids as agents exhibiting specific anticancer activity against MMPs. The primary aim of this study is to elucidate the diverse functions associated with MMP production in cancer and to investigate the potential of flavonoids in modulating MMP expression to inhibit metastasis.

Scoparone induces autophagic cell death via the PAK1/AKT axis in colorectal cancer

Colorectal cancer (CRC) is one of most common malignancies worldwide, yet curative therapy remains a clinical challenge. Here, we demonstrate that scoparone (Scop), a traditional Chinese medicine monomer, inhibits the growth of CRC cells both in vitro and in vivo. Further studies found that Scop treatment induces complete autophagic flux in CRC cells, while inhibition of autophagy markedly represses the antiproliferative activities of Scop, suggesting an antitumour property of Scop-induced autophagy in CRC. Mechanistically, Scop induced autophagy initiation by reducing P21-activated kinase 1 (PAK1) expression and subsequently repressing the AKT/mTOR signaling pathway. Collectively, our study suggests that Scop is a potential anti-CRC therapeutic option and provides an underlying molecular mechanism for its antitumour effect in CRC.

The role of flavonoids in the regulation of epithelial-mesenchymal transition in cancer: A review on targeting signaling pathways and metastasis

One of the hallmarks of cancer is metastasis, a process that entails the spread of cancer cells to distant regions in the body, culminating in tumor formation in secondary organs. Importantly, the proinflammatory environment surrounding cancer cells further contributes to cancer cell transformation and extracellular matrix destruction. During metastasis, front-rear polarity and emergence of migratory and invasive features are manifestations of epithelial-mesenchymal transition (EMT). A variety of transcription factors (TFs) are implicated in the execution of EMT, the most prominent belonging to the Snail Family Transcriptional Repressor (SNAI) and Zinc Finger E-Box Binding Homeobox (ZEB) families of TFs. These TFs are regulated by interaction with specific microRNAs (miRNAs), as miR34 and miR200. Among the several secondary metabolites produced in plants, flavonoids constitute a major group of bioactive molecules, with several described effects including antioxidant, antiinflammatory, antidiabetic, antiobesogenic, and anticancer effects. This review scrutinizes the modulatory role of flavonoids on the activity of SNAI/ZEB TFs and on their regulatory miRNAs, miR-34, and miR-200. The modulatory role of flavonoids can attenuate mesenchymal features and stimulate epithelial features, thereby inhibiting and reversing EMT. Moreover, this modulation is concomitant with the attenuation of signaling pathways involved in diverse processes as cell proliferation, cell growth, cell cycle progression, apoptosis inhibition, morphogenesis, cell fate, cell migration, cell polarity, and wound healing. The antimetastatic potential of these versatile compounds is emerging and represents an opportunity for the synthesis of more specific and potent agents.

Analysis of some flavonoids for inhibitory mechanism against cancer target phosphatidylinositol 3-kinase (PI3K) using computational tool

Cancer has been one of the leading causes of mortality worldwide over the past few years. Some progress has been made in the development of more effective cancer therapeutics, resulting in improved survival rates. However, the desired outcome in the form of successful treatment is yet to be achieved. There is high demand for the development of innovative, inexpensive, and effective anticancer treatments using natural resources. Natural compounds have been increasingly discovered and used for cancer therapy owing to their high molecular diversity, novel biofunctionality, and minimal side effects. These compounds can be utilized as chemopreventive agents because they can efficiently inhibit cell growth, control cell cycle progression, and block several tumor-promoting signaling pathways. PI3K is an important upstream protein of the PI3K-Akt-mTOR pathway and a well-established cancer therapeutic target. This study aimed to explore the small molecules, natural flavonoids, viz. quercetin, luteolin, kaempferol, genistein, wogonin, daidzein, and flavopiridol for PI3Kγ kinase activity inhibition. In this study, the binding pose, interacting residues, molecular interactions, binding energies, and dissociation constants were investigated. Our results showed that these flavonoids bound well with PI3Kγ with adequate binding strength scores and binding energy ranging from (-8.19 to -8.97 Kcal/mol). Among the explored ligands, flavopiridol showed the highest binding energy of -8.97 Kcal/mol, dock score (-44.40), and dissociation constant term, p K d of 6.58 against PI3Kγ. Based on the above results, the stability of the most promising ligand, flavopiridol, against PI3Kγ was evaluated by molecular dynamics simulations for 200 ns, confirming the stable flavopiridol and PI3Kγ complex. Our study suggests that among the selected flavonoids specifically flavopiridol may act as potential inhibitors of PI3Kγ and could be a therapeutic alternative to inhibit the PI3Kγ pathway, providing new insights into rational drug discovery research for cancer therapy.

Caffeic Acid Phenethyl Ester (CAPE) Synergistically Enhances Paclitaxel Activity in Ovarian Cancer Cells

Caffeic acid phenethyl ester (CAPE) belongs to the phenols found in propolis. It has already shown strong antiproliferative, cytotoxic and pro-apoptotic activities against head and neck cancers and against breast, colorectal, lung and leukemia cancer cells. Ovarian cancer is one of the most dangerous gynecological cancers. Its treatment involves intensive chemotherapy with platinum salts and paclitaxel (PTX). The purpose of this study was to evaluate whether the combined use of CAPE and paclitaxel increases the effectiveness of chemotherapeutic agents. The experiment was performed on three ovarian cancer lines: OV7, HTB78, and CRL1572. The effect of the tested compounds was assessed using H-E staining, a wound-healing test, MTT and the cell death detection ELISAPLUS test. The experiment proved that very low doses of PTX (10 nM) showed a cytotoxic effect against all the cell lines tested. Also, the selected doses of CAPE had a cytotoxic effect on the tested ovarian cancer cells. An increase in the cytotoxic effect was observed in the OV7 line after the simultaneous administration of 10 nM PTX and 100 µM CAPE. The increase in the cytotoxicity was dependent on the CAPE dosage (50 vs. 100 µM) and on the duration of the experiment. In the other cell lines tested, the cytotoxic effect of PTX did not increase after the CAPE administration. The administration of PTX together with CAPE increased the percentage of apoptotic cells in the tested ovarian cancer cell lines. Moreover, the simultaneous administration of PTX and CAPE enhanced the anti-migration activity of the chemotherapeutic used in this study.

Study the inhibitory effect and mechanism of the ethanol extract of deziyangxin on LLC cells

Background

Chinese Tibetan medicine plays a crucial role in complementary anti-tumor treatments. This article aims to investigate the inhibitory effect of the alcoholic extract of Tibetan medicine Deziyangxin (DZYX) on the proliferation and migration of non-small cell lung cancer (NSCLC) cells, specifically LLC cells, as well as explore its potential mechanism of action.

Methods

The effect of the alcoholic extract on LLC cell viability was assessed using the CCK-8 method. The proliferation of LLC cells was evaluated using the EdU (5-Acetyl-2'-deoxyuridine) assay. Transwell assays were conducted to measure cell metastasis. Western blot analysis was performed to assess the expression of Cleaved Caspase-3, Bcl-2, Beciln-1, indicating the impact of DZYX on apoptosis and autophagy in LLC cells. Furthermore, the anti-tumor mechanism of DZYX was explored through transcriptome research and detection of Akt, p-Akt, p-mTOR protein levels.

Results

The ethanol extract of DZYX exhibited a concentration-dependent and time-dependent inhibitory effect on LLC cell viability, with an IC50 of 406.1 μg/ml. Moreover, the ethanol extract of DZYX significantly reduced the migration ability of LLC cells. Additionally, the alcoholic extract of DZYX upregulated the expression of Cleaved Caspase-3 and Beciln-1 proteins, while downregulating the expression of Bcl-2 in LLC cells. Importantly, DZYX ethanol extract down regulated the expression of Akt and p-mTOR proteins in LLC cells, which combined with transcriptome results indicated that the drug exerted a multi-target and multi-pathway effect, primarily related to inhibiting the activation of the PI3K/AKT/m-TOR signaling pathway.

Conclusion

The alcoholic extract of DZYX demonstrates inhibitory effects on LLC cells, promoting apoptosis and autophagy. It is hypothesized that its anti-tumor mechanism is associated with the PI3K/AKT/m-TOR pathway.

Advances in mitophagy and mitochondrial apoptosis pathway-related drugs in glioblastoma treatment

Glioblastoma (GBM) is the most common malignant tumor of the central nervous system (CNS). It is a leading cause of death among patients with intracranial malignant tumors. GBM exhibits intra- and inter-tumor heterogeneity, leading to drug resistance and eventual tumor recurrence. Conventional treatments for GBM include maximum surgical resection of glioma tissue, temozolomide administration, and radiotherapy, but these methods do not effectively halt cancer progression. Therefore, development of novel methods for the treatment of GBM and identification of new therapeutic targets are urgently required. In recent years, studies have shown that drugs related to mitophagy and mitochondrial apoptosis pathways can promote the death of glioblastoma cells by inducing mitochondrial damage, impairing adenosine triphosphate (ATP) synthesis, and depleting large amounts of ATP. Some studies have also shown that modern nano-drug delivery technology targeting mitochondria can achieve better drug release and deeper tissue penetration, suggesting that mitochondria could be a new target for intervention and therapy. The combination of drugs targeting mitochondrial apoptosis and autophagy pathways with nanotechnology is a promising novel approach for treating GBM.This article reviews the current status of drug therapy for GBM, drugs targeting mitophagy and mitochondrial apoptosis pathways, the potential of mitochondria as a new target for GBM treatment, the latest developments pertaining to GBM treatment, and promising directions for future research.

Regulatory Roles of Flavonoids in Caspase-11 Non-Canonical Inflammasome-Mediated Inflammatory Responses and Diseases

Inflammasomes are multiprotein complexes that activate inflammatory responses by inducing pyroptosis and secretion of pro-inflammatory cytokines. Along with many previous studies on inflammatory responses and diseases induced by canonical inflammasomes, an increasing number of studies have demonstrated that non-canonical inflammasomes, such as mouse caspase-11 and human caspase-4 inflammasomes, are emerging key players in inflammatory responses and various diseases. Flavonoids are natural bioactive compounds found in plants, fruits, vegetables, and teas and have pharmacological properties in a wide range of human diseases. Many studies have successfully demonstrated that flavonoids play an anti-inflammatory role and ameliorate many inflammatory diseases by inhibiting canonical inflammasomes. Others have demonstrated the anti-inflammatory roles of flavonoids in inflammatory responses and various diseases, with a new mechanism by which flavonoids inhibit non-canonical inflammasomes. This review discusses recent studies that have investigated the anti-inflammatory roles and pharmacological properties of flavonoids in inflammatory responses and diseases induced by non-canonical inflammasomes and further provides insight into developing flavonoid-based therapeutics as potential nutraceuticals against human inflammatory diseases.

The multifaceted roles of natural products in mitochondrial dysfunction

Mitochondria are the primary source of energy production in cells, supporting the metabolic demand of tissue. The dysfunctional mitochondria are implicated in various diseases ranging from neurodegeneration to cancer. Therefore, regulating dysfunctional mitochondria offers a new therapeutic opportunity for diseases with mitochondrial dysfunction. Natural products are pleiotropic and readily obtainable sources of therapeutic agents, which have broad prospects in new drug discovery. Recently, many mitochondria-targeting natural products have been extensively studied and have shown promising pharmacological activity in regulating mitochondrial dysfunction. Hence, we summarize recent advances in natural products in targeting mitochondria and regulating mitochondrial dysfunction in this review. We discuss natural products in terms of their mechanisms on mitochondrial dysfunction, including modulating mitochondrial quality control system and regulating mitochondrial functions. In addition, we describe the future perspective and challenges in the development of mitochondria-targeting natural products, emphasizing the potential value of natural products in mitochondrial dysfunction.

Olea europaea Leaf Phenolics Oleuropein, Hydroxytyrosol, Tyrosol, and Rutin Induce Apoptosis and Additionally Affect Temozolomide against Glioblastoma: In Particular, Oleuropein Inhibits Spheroid Growth by Attenuating Stem-like Cell Phenotype

The effects of Olea europaea leaf extract (OLE) phenolics, including oleuropein (OL), hydroxytyrosol (HT), tyrosol (TYR), and rutin against glioblastoma (GB), independently and in combination with temozolomide (TMZ), were investigated in T98G and A172 cells. Cell growth was assessed by WST-1, real-time cell analysis, colony formation, and cell cycle distribution assays. A dual acridine orange propidium iodide (AO/PI) staining and annexin V assay determined cell viability. A sphere-forming assay, an intracellular oxidative stress assay, and the RNA expression of CD133 and OCT4 investigated the GB stem-like cell (GSC) phenotype. A scratch wound-healing assay evaluated migration capacity. OL was as effective as OLE in terms of apoptosis promotion (p < 0.001) and GSC inhibition (p < 0.001). HT inhibited cell viability, GSC phenotype, and migration rate (p < 0.001), but its anti-GB effect was less than the total effect of OLE alone. Rutin decreased reactive oxygen species production and inhibited colony formation and cell migration (p < 0.001). TYR demonstrated the least effect. The additive effects of OL, HT, TYR and rutin with TMZ were significant (p < 0.001). Our data suggest that OL may represent a novel therapeutic approach against GB cells, while HT and rutin show promise in increasing the efficacy of TMZ therapy.

Anticancer Mechanism of Flavonoids on High-Grade Adult-Type Diffuse Gliomas

High-grade adult-type diffuse gliomas are the most common and deadliest malignant adult tumors of the central nervous system. Despite the advancements in the multimodality treatment of high-grade adult-type diffuse gliomas, the five-year survival rates still remain poor. The biggest challenge in treating high-grade adult-type diffuse gliomas is the intra-tumor heterogeneity feature of the glioma tumors. Introducing dietary flavonoids to the current high-grade adult-type diffuse glioma treatment strategies is crucial to overcome this challenge, as flavonoids can target several molecular targets. This review discusses the anticancer mechanism of flavonoids (quercetin, rutin, chrysin, apigenin, naringenin, silibinin, EGCG, genistein, biochanin A and C3G) through targeting molecules associated with high-grade adult-type diffuse glioma cell proliferation, apoptosis, oxidative stress, cell cycle arrest, migration, invasion, autophagy and DNA repair. In addition, the common molecules targeted by the flavonoids such as Bax, Bcl-2, MMP-2, MMP-9, caspase-8, caspase-3, p53, p38, Erk, JNK, p38, beclin-1 and LC3B were also discussed. Moreover, the clinical relevance of flavonoid molecular targets in high-grade adult-type diffuse gliomas is discussed with comparison to small molecules inhibitors: ralimetinib, AMG232, marimastat, hydroxychloroquine and chloroquine. Despite the positive pre-clinical results, further investigations in clinical studies are warranted to substantiate the efficacy and safety of the use of flavonoids on high-grade adult-type diffuse glioma patients.

Anticancer potential of oroxylin A: from mechanistic insight to synergistic perspectives

Oroxylin A (OA), a well-known constituent of the root of Scutellariae plants, has been used in ethnomedicine already for centuries in treating various neoplastic disorders. However, only recent molecular studies have revealed the different mechanisms behind its action, demonstrating antiproliferative, anti-inflammatory, and proapoptotic effects, restricting also the spread of cancer cells to distant organs. A variety of cellular targets and modulated signal transduction pathways regulated by OA have been determined in diverse cells derived from different malignant tissues. In this review article, these anticancer activities are thoroughly described, representing OA as a potential lead structure for the design of novel more potent anticancer medicines. In addition, co-effects of this natural compound with conventional anticancer agents are analyzed and the advantages provided by nanotechnological methods for more efficient application of OA are discussed. In this way, OA might represent an excellent example of using ethnopharmacological knowledge for designing modern medicines.

Current advances on the therapeutic potential of pinocembrin: An updated review

Pinocembrin (5,7-dihydroxyflavone) is a major flavonoid found in many plants, fungi and hive products, mainly honey and propolis. Several in vitro and preclinical studies revealed numerous pharmacological activities of pinocembrin including antioxidant, anti-inflammatory, antimicrobial, neuroprotective, cardioprotective and anticancer activities. Here, we comprehensively review and critically analyze the studies carried out on pinocembrin. We also discuss its potential mechanisms of action, bioavailability, toxicity, and clinical investigations. The wide therapeutic window of pinocembrin makes it a promising drug candidate for many clinical applications. We recommend some future perspectives to improve its pharmacokinetic and pharmacodynamic properties for better delivery that may also lead to new therapeutic advances.

Why Do Dietary Flavonoids Have a Promising Effect as Enhancers of Anthracyclines? Hydroxyl Substituents, Bioavailability and Biological Activity

Anthracyclines currently play a key role in the treatment of many cancers, but the limiting factor of their use is the widespread phenomenon of drug resistance and untargeted toxicity. Flavonoids have pleiotropic, beneficial effects on human health that, apart from antioxidant activity, are currently considered small molecules-starting structures for drug development and enhancers of conventional therapeutics. This paper is a review of the current and most important data on the participation of a selected series of flavonoids: chrysin, apigenin, kaempferol, quercetin and myricetin, which differ in the presence of an additional hydroxyl group, in the formation of a synergistic effect with anthracycline antibiotics. The review includes a characterization of the mechanism of action of flavonoids, as well as insight into the physicochemical parameters determining their bioavailability in vitro. The crosstalk between flavonoids and the molecular activity of anthracyclines discussed in the article covers the most important common areas of action, such as (1) disruption of DNA integrity (genotoxic effect), (2) modulation of antioxidant response pathways, and (3) inhibition of the activity of membrane proteins responsible for the active transport of drugs and xenobiotics. The increase in knowledge about the relationship between the molecular structure of flavonoids and their biological effect makes it possible to more effectively search for derivatives with a synergistic effect with anthracyclines and to develop better therapeutic strategies in the treatment of cancer.

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.

Molecular and Cellular Mechanisms of Propolis and Its Polyphenolic Compounds against Cancer

In recent years, interest in natural products such as alternative sources of pharmaceuticals for numerous chronic diseases, including tumors, has been renewed. Propolis, a natural product collected by honeybees, and polyphenolic/flavonoid propolis-related components modulate all steps of the cancer progression process. Anticancer activity of propolis and its compounds relies on various mechanisms: cell-cycle arrest and attenuation of cancer cells proliferation, reduction in the number of cancer stem cells, induction of apoptosis, modulation of oncogene signaling pathways, inhibition of matrix metalloproteinases, prevention of metastasis, anti-angiogenesis, anti-inflammatory effects accompanied by the modulation of the tumor microenvironment (by modifying macrophage activation and polarization), epigenetic regulation, antiviral and bactericidal activities, modulation of gut microbiota, and attenuation of chemotherapy-induced deleterious side effects. Ingredients from propolis also "sensitize" cancer cells to chemotherapeutic agents, likely by blocking the activation of the transcription factor nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB). In this review, we summarize the current knowledge related to the the effects of flavonoids and other polyphenolic compounds from propolis on tumor growth and metastasizing ability, and discuss possible molecular and cellular mechanisms involved in the modulation of inflammatory pathways and cellular processes that affect survival, proliferation, invasion, angiogenesis, and metastasis of the tumor.

Flavonoids as regulators of TIMPs expression in cancer: Consequences, opportunities, and challenges

Cancer is one of the leading causes of death in patients worldwide, where invasion and metastasis are directly responsible for this statement. Although cancer therapy has progressed in recent years, current therapeutic approaches are ineffective due to toxicity and chemoresistance. Therefore, it is essential to evaluate other treatment options, and natural products are a promising alternative as they show antitumor properties in different study models. This review describes the regulation of tissue inhibitors of metalloproteinases (TIMPs) expression and the role of flavonoids as molecules with the antitumor activity that targets TIMPs therapeutically. These inhibitors regulate tissue extracellular matrix (ECM) turnover; they inhibit matrix metalloproteinases (MMPs), cell migration, invasion, and angiogenesis and induce apoptosis in tumor cells. Data obtained in cell lines and in vivo models suggest that flavonoids are chemopreventive and cytotoxic against various types of cancer through several mechanisms. Flavonoids also regulate crucial signaling pathways such as focal adhesion kinase (FAK), phosphatidylinositol-3-kinase (PI3K)-Akt, signal transducer and activator of transcription 3 (STAT3), nuclear factor κB (NFκB), and mitogen-activated protein kinase (MAPK) involved in cancer cell migration, invasion, and metastasis. All these data reposition flavonoids as excellent candidates for use in cancer therapy.

5-Fluorouracil and Curcumin Combination Coated with Pectin and Its Strategy towards Titanium Dioxide, Dimethylhydrazine Colorectal Cancer Model with the Evaluation of the Blood Parameters

Colorectal cancer is considered the third most common cancer and the second leading cause of death globally. It has been proven that titanium dioxide nanoparticles produce oxidative stress and can lead to chronic inflammation, which could turn into diseases like cancer, cardiovascular disorders, diabetes, and so on. To evaluate the effect of 5-fluorouracil (5-FU) curcumin (CUR) conjugate coated with pectin on colorectal cancer induced by titanium dioxide nanoparticles (TiO₂-NPs) and dimethylhydrazine (DMH), male rats were administered TiO₂-NPs (5 mg/kg) orally and DMH (1 mg/kg) peritoneally for 70 days and treated with 5-FU (60 mg/kg) and CUR (240 mg/kg) conjugate (1:4 ratio) coated with pectin. The bodyweight of the animals was evaluated, and the blood sugar level was calculated. Further blood and plasma analyses were conducted. Hematological parameters, antioxidant parameters, and biochemical estimation were taken into consideration. The TiO₂-NPs level in the blood and colorectal region was also calculated. With the induction of colon cancer using TiO₂-NPs and DMH, a significant increase in the body weight of the animals was seen; eventually, with treatment, it was reduced. The bodyweight increase was due to an increase in the blood sugar level. There were also significant changes in the hematological parameters and biochemical estimation reports when comparing those of the positive control, negative control, and treated groups. No significant effect on biochemical estimation reports was seen. Conclusions: These reports suggest that 5-FU CUR conjugate coated with pectin helps in the management of colorectal cancer induced by TiO₂-NPs and DMH.

From Intestinal Epithelial Homeostasis to Colorectal Cancer: Autophagy Regulation in Cellular Stress

The intestinal epithelium is continuously exposed to abundant stress stimuli, which relies on an evolutionarily conserved process, autophagy, to maintain its homeostasis by degrading and recycling unwanted and damaged intracellular substances. Otherwise, disruption of this balance will result in the development of a wide range of disorders, including colorectal cancer (CRC). Dysregulated autophagy is implicated in the regulation of cellular responses to stress during the development, progression, and treatment of CRC. However, experimental investigations addressing the impact of autophagy in different phases of CRC have generated conflicting results, showing that autophagy is context-dependently related to CRC. Thus, both inhibition and activation of autophagy have been proposed as therapeutic strategies against CRC. Here, we will discuss the multifaceted role of autophagy in intestinal homeostasis and CRC, which may provide insights for future research directions.

Flavonoids Targeting the mTOR Signaling Cascades in Cancer: A Potential Crosstalk in Anti-Breast Cancer Therapy

Cancer is one of the leading causes of death worldwide. Breast cancer is the second leading cause of death in women, with triple-negative breast cancer being the most lethal and aggressive form. Conventional therapies, such as radiation, surgery, hormonal, immune, gene, and chemotherapy, are widely used, but their therapeutic efficacy is limited due to adverse side effects, toxicities, resistance, recurrence, and therapeutic failure. Many molecules have been identified and investigated as potential therapeutic agents for breast cancer, with a focus on various signaling pathways. Flavonoids are a versatile class of phytochemicals that have been used in cancer treatment to overcome issues with traditional therapies. Cell proliferation, growth, apoptosis, autophagy, and survival are all controlled by mammalian target of rapamycin (mTOR) signaling. Flavonoids target mTOR signaling in breast cancer, and when this signaling pathway is regulated or deregulated, various signaling pathways provide potential therapeutic means. The role of various flavonoids as phytochemicals in targeting mTOR signaling pathways in breast cancer is highlighted in this review.

Novel Therapeutic Strategies for Ischemic Stroke: Recent Insights into Autophagy

Stroke is one of the leading causes of death and disability worldwide. Autophagy is a conserved cellular catabolic pathway that maintains cellular homeostasis by removal of damaged proteins and organelles, which is critical for the maintenance of energy and function homeostasis of cells. Accumulating evidence demonstrates that autophagy plays important roles in pathophysiological mechanisms under ischemic stroke. Previous investigations show that autophagy serves as a “double-edged sword” in ischemic stroke as it can either promote the survival of neuronal cells or induce cell death in special conditions. Following ischemic stroke, autophagy is activated or inhibited in several cell types in brain, including neurons, astrocytes, and microglia, as well as microvascular endothelial cells, which involves in inflammatory activation, modulation of microglial phenotypes, and blood-brain barrier permeability. However, the exact mechanisms of underlying the role of autophagy in ischemic stroke are not fully understood. This review focuses on the recent advances regarding potential molecular mechanisms of autophagy in different cell types. The focus is also on discussing the “double-edged sword” effect of autophagy in ischemic stroke and its possible underlying mechanisms. In addition, potential therapeutic strategies for ischemic stroke targeting autophagy are also reviewed.

Potential Therapeutic Action of Autophagy in Gastric Cancer Managements: Novel Treatment Strategies and Pharmacological Interventions

Gastric cancer (GC), second most leading cause of cancer-associated mortality globally, is the cancer of gastrointestinal tract in which malignant cells form in lining of the stomach, resulting in indigestion, pain, and stomach discomfort. Autophagy is an intracellular system in which misfolded, aggregated, and damaged proteins, as well as organelles, are degraded by the lysosomal pathway, and avoiding abnormal accumulation of huge quantities of harmful cellular constituents. However, the exact molecular mechanism of autophagy-mediated GC management has not been clearly elucidated. Here, we emphasized the role of autophagy in the modulation and development of GC transformation in addition to underlying the molecular mechanisms of autophagy-mediated regulation of GC. Accumulating evidences have revealed that targeting autophagy by small molecule activators or inhibitors has become one of the greatest auspicious approaches for GC managements. Particularly, it has been verified that phytochemicals play an important role in treatment as well as prevention of GC. However, use of combination therapies of autophagy modulators in order to overcome the drug resistance through GC treatment will provide novel opportunities to develop promising GC therapeutic approaches. In addition, investigations of the pathophysiological mechanism of GC with potential challenges are urgently needed, as well as limitations of the modulation of autophagy-mediated therapeutic strategies. Therefore, in this review, we would like to deliver an existing standard molecular treatment strategy focusing on the relationship between chemotherapeutic drugs and autophagy, which will help to improve the current treatments of GC patients.

Clinical Application of Tumor Vascular Disrupting Therapy: A Systematic Review and Meta-Analysis

Purpose

The occurrence, progression, invasion and metastasis of tumors depend on a tumor vascular network. Vascular disrupting agents (VDAs) are a new class of drugs targeting the tumor vasculature, by blocking the existing tumor blood vessels. However, there is no clear consensus on the clinical efficacy of tumor vascular disrupting therapy. In this study, we performed the first systematic review and meta-analysis of published clinical trials focused on tumor vascular disrupting therapies.

Materials and Methods

We searched PubMed, EMBASE, and the Cochrane Library to identify clinical trials that used VDAs to treat tumors. After literature screening and data extraction, according to inclusion and exclusion labels, meta-analysis was performed using RevMan5.3 software.

Results

In this meta-analysis, we included 2659 patients from eight randomized controlled trials involving non-small-cell lung cancer, prostate, epithelial ovarian, fallopian tube, and primary peritoneal carcinoma. Compared with the control arm, the experimental arm exhibited an effective improvement of 0.5-year and 1-year survival, as well as the 6-month progression-free survival rate. There was no significant difference between patients in the experimental compared to the control arm with respect to objective response and disease control rates, and 12-month progression-free survival.

Conclusion

Vascular disrupting therapy can effectively prolong the survival of cancer patients. However, for indicators of short-term efficacy, such as objective response rate and disease control rate, there is still a lack of high-quality, large-scale clinical trial data to confirm the effectiveness of VDAs.

Rutin (Bioflavonoid) as Cell Signaling Pathway Modulator: Prospects in Treatment and Chemoprevention

Cancer is a complex ailment orchestrated by numerous intrinsic and extrinsic pathways. Recent research has displayed a deep interest in developing plant-based cancer therapeutics for better management of the disease and limited side effects. A wide range of plant-derived compounds have been reported for their anticancer potential in the quest of finding an effective therapeutic approach. Rutin (vitamin P) is a low-molecular weight flavonoid glycoside (polyphenolic compound), abundantly present in various vegetables, fruits (especially berries and citrus fruits), and medicinal herbs. Numerous studies have delineated several pharmacological properties of rutin such as its antiprotozoal, antibacterial, anti-inflammatory, antitumor, antiviral, antiallergic, vasoactive, cytoprotective, antispasmodic, hypolipidemic, antihypertensive, and antiplatelet properties. Specifically, rutin-mediated anticancerous activities have been reported in several cancerous cell lines, but the most common scientific evidence, encompassing several molecular processes and interactions, including apoptosis pathway regulation, aberrant cell signaling pathways, and oncogenic genes, has not been thoroughly studied. In this direction, we attempted to project rutin-mediated oncogenic pathway regulation in various carcinomas. Additionally, we also incorporated advanced research that has uncovered the notable potential of rutin in the modulation of several key cellular functions via interaction with mRNAs, with major emphasis on elucidating direct miRNA targets of rutin as well as the process needed to transform these approaches for developing novel therapeutic interventions for the treatment of several cancers.