Fisetin Deters Cell Proliferation, Induces Apoptosis, Alleviates Oxidative Stress and Inflammation in Human Cancer Cells, HeLa

Fisetin as a senotherapeutic agent: Evidence and perspectives for age-related diseases

Fisetin, a flavonoid naturally occurring in plants, fruits, and vegetables, has recently gained attention for its potential role as a senotherapeutic agent for the treatment of age-related chronic diseases. Senotherapeutics target senescent cells, which accumulate with age and disease, in both circulating immune cell populations and solid organs and tissues. Senescent cells contribute to development of many chronic diseases, primarily by eliciting systemic chronic inflammation through their senescence-associated secretory phenotype. Here, we explore whether fisetin as a senotherapeutic can eliminate senescent cells, and thereby alleviate chronic diseases, by examining current evidence from in vitro studies and animal models that investigate fisetin's impact on age-related diseases, as well as from phase I/II trials in various patient populations. We discuss the application of fisetin in humans, including challenges and future directions. Our review of available data suggests that targeting senescent cells with fisetin offers a promising strategy for managing multiple chronic diseases, potentially transforming future healthcare for older and multimorbid patients. However, further studies are needed to establish the safety, pharmacokinetics, and efficacy of fisetin as a senotherapeutic, identify relevant and reliable outcome measures in human trials, optimize dosing, and better understand the possible limitations of fisetin as a senotherapeutic agent.

Research advances in signaling pathways related to the malignant progression of HSIL to invasive cervical cancer: A review

The progression of high-grade squamous intraepithelial lesion (HSIL) to invasive cervical cancer (ICC) is a complex process involving persistent human papillomavirus (HPV) infection and changes in signal transduction regulation, energy and material metabolism, cell proliferation, autoimmune, and other biological process in vaginal microenvironment and immune microenviroment. Signaling pathways are a series of interacting molecules in cells that regulate various physiological functions of cells, such as growth, differentiation, metabolism, and death. In the progression of HSIL to ICC, abnormal activation or inhibition in signaling pathways plays an essensial role. This review presented some signaling pathways related to the malignant progression of HSIL to ICC, including p53, Rb, PI3K/AKT/mTOR, Wnt/β-catenin, Notch, NF-κB, MAPK, TGF-β, JAK-STAT, Hippo, and Hedgehog. The molecular mechanisms involved in the biological process of pathway regulation were also analyzed, in order to illustrate the molecular pathway of HSIL progression to ICC and provide references for the development of more effective prevention and treatment methods.

Fisetin disrupts mitochondrial homeostasis via superoxide dismutase 2 acetylation in pancreatic adenocarcinoma

Pancreatic adenocarcinoma (PDAC) is one of the most lethal malignant tumors with an urgent need for precision medicine strategies. The present study seeks to assess the antitumor effects of fisetin, and characterize its impact on PDAC. Multi-omic approaches include proteomic, transcriptomic, and metabolomic analyses. Further validation includes the assessment of mitochondria-derived reactive oxygen species (mtROS), mitochondrial membrane potential, as well as ATP generation. Molecular docking, immunoprecipitation, and proximity ligation assay were used to detect the interactions among fiseitn, superoxide dismutase 2 (SOD2), and sirtuin 2 (SIRT2). We showed that fisetin disrupted mitochondrial homeostasis and induced SOD2 acetylation in PDAC. Further, we produced site mutants to determine that fisetin-induced mtROS were dependent on SOD2 acetylation. Fisetin inhibited SIRT2 expression, thus blocking SOD2 deacetylation. SIRT2 overexpression could impede fisetin-induced SOD2 acetylation. Additionally, untargeted metabolomic analysis revealed an acceleration of folate metabolism with fisetin. Collectively, our findings suggest that fisetin disrupts mitochondrial homeostasis, eliciting an important cancer-suppressive role; thus, fisetin may serve as a promising therapeutic for PDAC.

Fisetin induces G2/M phase arrest and caspase-mediated cleavage of p21Cip1 and p27Kip1 leading to apoptosis and tumor growth inhibition in HNSCC

The anticancer potential and associated mechanisms of flavonoid fisetin are yet to be fully investigated on human head and neck squamous cell carcinoma (HNSCC). In the present study, fisetin (25-75 µM for 24-48 h) dose-dependently inhibited growth and induced death in HNSCC Cal33 and UM-SCC-22B cells, without showing any death in normal cells. Fisetin (25-50 µM) induced G2/M phase arrest via decrease in Cdc25C, CDK1, cyclin B1 expression, and an increase in p53(S15). A concentration-dependent increase in fisetin-induced DNA damage and apoptosis in HNSCC cells was authenticated by comet assay, gamma-H2A.X(S139) phosphorylation, and marked cleavage of PARP protein. Interestingly, fisetin-induced cell death occurred independently of p53 and reactive oxygen species production. The activation of JNK and inhibition of PI3K/Akt, ERK1/2, EGFR, and STAT-3 signaling were identified. Further, fisetin-induced apoptosis was mediated, in part, via p21Cip1 and p27Kip1 cleavage by caspase, which was reversed by z-VAD-FMK, a pan-caspase inhibitor. Subsequently, fisetin was also found to induce autophagy; nevertheless, autophagy attenuation exaggerated apoptosis. Oral fisetin (50 mg/kg body weight) treatment to establish Cal33 xenograft in mice for 19 days showed 73% inhibition in tumor volume (p < 0.01) along with a decrease in Ki67-positive cells and an increase in cleaved caspase-3 level in tumors. Consistent with the effect of 50 µM fisetin in vitro, the protein levels of p21Cip1 and P27Kip1 were also decreased by fisetin in tumors. Together, these findings showed strong anticancer efficacy of fisetin against HNSCC with downregulation of EGFR-Akt/ERK1/2-STAT-3 pathway and activation of JNK/c-Jun, caspases and caspase-mediated cleavage of p21Cip1 and p27Kip1.

Delineating the Antiapoptotic Property of Apigenin as an Antitumor Agent: A Computational and In Vitro Study on HeLa Cells

Apigenin, a flavonoid, is reported to have multiple health benefits including cancer prevention; this study evaluates the drug likeliness and Swiss ADME properties of apigenin. Apoptosis, which is a key hallmark of cancer, is associated with the deregulation of the balance between proapoptotic proteins and antiapoptotic proteins such as BCL-2,BCL-xl, BFL-1, BCL-w, BRAG-16, and MCL-1. The docking studies of apigenin with the mentioned proteins was performed to identify the interactions between the ligand and proteins, which suggested that apigenin was able to bind to most of the proteins similar to the inhibitory molecules of its native structure. A remarkable reduction in the total energy after energy minimization of apigenin-antiapoptotic protein complexes suggested increased stability of the docked complexes. The same complexes were found to be stable over a 10 ns period of molecular simulation at 300 K. These findings advocated the study to evaluate apigenin's potential to inhibit the HeLa cells at 5, 10, and 15 μM concentrations in the clonogenic assay. Apigenin inhibited the colony-forming ability of HeLa cells in a dose-dependent manner over a fortnight. Light microscopy of the treated cells displayed the morphological evidence characteristic of apoptosis in HeLa cells such as blebbing, spike formation, cytoplasmic oozing, and nuclear fragmentation. Thus, these results clearly indicate that apigenin may be used as a potential chemopreventive agent in cervical cancer management.

Molecular mechanisms of flavonoids in myocardial ischemia reperfusion injury: Evidence from in-vitro and in-vivo studies

OBJECTIVES

Flavonoids are polyphenolic compounds found in a wide range of foods, including fruits, vegetables, tea plants, and other natural products. They have been mainly classified as flavanols, flavonols, flavones, isoflavones, flavanones, and flavanonols. In this comprehensive review, we will discuss preclinical pieces of evidence on the potential of flavonoids for the prevention/treatment of myocardial ischemia-reperfusion (IR) injury.

KEY FINDINGS

In-vitro and in-vivo studies have shown that flavonoids play an important role in preventing ischemic heart disease (IHD). They possess strong anti-oxidant, anti-inflammatory, anti-bacterial, anti-thrombotic, anti-apoptotic, and anti-carcinogenic activities. In addition, at a molecular level, flavonoids also modulate various pathways like MAPK, NFκB etc. to confer beneficial effects.

SUMMARY

The current review of flavonoids in myocardial ischemia-reperfusion injury furnishes updated information that could drive future research. The in-vitro and in-vivo experiments have demonstrated various favourable pharmacological properties of flavonoids. This review provides valuable information to conduct clinical studies, validating the safety aspects of flavonoids in the clinical domain.

Modulation of long noncoding RNAs by polyphenols as a novel potential therapeutic approach in lung cancer: A comprehensive review

Lung cancer stands as a formidable global health challenge, necessitating innovative therapeutic strategies. Polyphenols, bioactive compounds synthesized by plants, have garnered attention for their diverse health benefits, particularly in combating various cancers, including lung cancer. The advent of whole-genome and transcriptome sequencing technologies has illuminated the pivotal roles of long noncoding RNAs (lncRNAs), operating at epigenetic, transcriptional, and posttranscriptional levels, in cancer progression. This review comprehensively explores the impact of polyphenols on both oncogenic and tumor-suppressive lncRNAs in lung cancer, elucidating on their intricate regulatory mechanisms. The comprehensive examination extends to the potential synergies when combining polyphenols with conventional treatments like chemotherapy, radiation, and immunotherapy. Recognizing the heterogeneity of lung cancer subtypes, the review emphasizes the need for the integration of nanotechnology for optimized polyphenol delivery and personalized therapeutic approaches. In conclusion, we collect the latest research, offering a holistic overview of the evolving landscape of polyphenol-mediated modulation of lncRNAs in lung cancer therapy. The integration of polyphenols and lncRNAs into multidimensional treatment strategies holds promise for enhancing therapeutic efficacy and navigating the challenges associated with lung cancer treatment.

Cubosomal nanoformulation increase invitro dissolution and anticancer activity of Fisetin in A549 lung cancer cells

Aim: To prepare fisetin (FIS) cubosomal nanoformulation to increase aqueous solubility and anticancer activity. Methods: Top-down method using glyceryl monooleate (GMO) and Pluronic F-127. Results: Optimized using 2% GMO and 1% Pluronic F-127, reported 93.07 nm particle size, 80.10% drug entrapment, and reports more than 50% enhanced in vitro drug release than native FIS. MTT assay reports IC50 Values of FIS 16.59 μg/ml and optimized cubosomal FIS nanoformulation (FISCUB) 12.18 μg/ml. The colony numbers observed in clonogenic assay for FISCUB were 8.33 ± 0.58 and FIS 11.67 ± 1.15. In flow cytometry study, apoptotic cells in FISCUB and FIS-treated A549 cells were found to be 33.4 and 6.83% respectively. Conclusion: A stable cubosomal nanoformulation of FIS showed enhanced aqueous solubility and anticancer activity.

Selected Flavonols Targeting Cell Death Pathways in Cancer Therapy: The Latest Achievements in Research on Apoptosis, Autophagy, Necroptosis, Pyroptosis, Ferroptosis, and Cuproptosis

The complex and multi-stage processes of carcinogenesis are accompanied by a number of phenomena related to the potential involvement of various chemopreventive factors, which include, among others, compounds of natural origin such as flavonols. The use of flavonols is not only promising but also a recognized strategy for cancer treatment. The chemopreventive impact of flavonols on cancer arises from their ability to act as antioxidants, impede proliferation, promote cell death, inhibit angiogenesis, and regulate the immune system through involvement in diverse forms of cellular death. So far, the molecular mechanisms underlying the regulation of apoptosis, autophagy, necroptosis, pyroptosis, ferroptosis, and cuproptosis occurring with the participation of flavonols have remained incompletely elucidated, and the results of the studies carried out so far are ambiguous. For this reason, one of the therapeutic goals is to initiate the death of altered cells through the use of quercetin, kaempferol, myricetin, isorhamnetin, galangin, fisetin, and morin. This article offers an extensive overview of recent research on these compounds, focusing particularly on their role in combating cancer and elucidating the molecular mechanisms governing apoptosis, autophagy, necroptosis, pyroptosis, ferroptosis, and cuproptosis. Assessment of the mechanisms underlying the anticancer effects of compounds in therapy targeting various types of cell death pathways may prove useful in developing new therapeutic regimens and counteracting resistance to previously used treatments.

Exploring the effects of Dasatinib, Quercetin, and Fisetin on DNA methylation clocks: a longitudinal study on senolytic interventions

Senolytics, small molecules targeting cellular senescence, have emerged as potential therapeutics to enhance health span. However, their impact on epigenetic age remains unstudied. This study aimed to assess the effects of Dasatinib and Quercetin (DQ) senolytic treatment on DNA methylation (DNAm), epigenetic age, and immune cell subsets. In a Phase I pilot study, 19 participants received DQ for 6 months, with DNAm measured at baseline, 3 months, and 6 months. Significant increases in epigenetic age acceleration were observed in first-generation epigenetic clocks and mitotic clocks at 3 and 6 months, along with a notable decrease in telomere length. However, no significant differences were observed in second and third-generation clocks. Building upon these findings, a subsequent investigation evaluated the combination of DQ with Fisetin (DQF), a well-known antioxidant and antiaging senolytic molecule. After one year, 19 participants (including 10 from the initial study) received DQF for 6 months, with DNAm assessed at baseline and 6 months. Remarkably, the addition of Fisetin to the treatment resulted in non-significant increases in epigenetic age acceleration, suggesting a potential mitigating effect of Fisetin on the impact of DQ on epigenetic aging. Furthermore, our analyses unveiled notable differences in immune cell proportions between the DQ and DQF treatment groups, providing a biological basis for the divergent patterns observed in the evolution of epigenetic clocks. These findings warrant further research to validate and comprehensively understand the implications of these combined interventions.

Fisetin suppresses ferroptosis through Nrf2 and attenuates intervertebral disc degeneration in rats

Low back pain, primarily caused by intervertebral disc degeneration (IVDD), lacks effective pharmacological treatments. Oxidative stress has been identified as a significant contributor to IVDD. This study aims to establish an in vitro model of IVDD induced by oxidative stress and identify potential therapeutic agents and their underlying mechanisms. By screening the natural product library, fisetin emerged as the most promising compound in suppressing cell death induced by oxidative stress in nucleus pulposus cells (NPCs). Furthermore, our investigation revealed that the cell death induced by oxidative stress was predominantly associated with ferroptosis, and fisetin demonstrated the ability to inhibit ferroptosis in NPCs. Mechanistic exploration suggested that the impact of fisetin on ferroptosis may be mediated through the Nrf2/HO-1 (Nuclear factor erythroid 2-related factor 2/heme oxygenase-1) axis. Notably, the in vivo study demonstrated that fisetin could alleviate IVDD in rats. These findings highlight fisetin as a potential therapeutic option for IVDD and implicate the involvement of the Nrf2/HO-1 pathway in its mechanism of action.

Roles of PTEN gene methylation in Se-CQDs induced mitochondrial apoptosis of osteosarcoma cells

Biocompatible carbon quantum dots (CQDs) containing anti-osteosarcoma elements are intriguing therapeutics promising for bioimaging and tumor therapy. However, how the anti-osteosarcoma element doped in the structure of such CQDs triggers tumor inhibition remains unclear. Here, selenium-doped CQDs (Se-CQDs) are developed via a one-step hydrothermal route using discarded orange peel as a carbon source and structurally characterized by various physicochemical techniques. The biocompatibility and anti-osteosarcoma efficacy are deeply evaluated using animal and cell models. The resulting spherical Se-CQDs, with a 3-7 nm diameter, possess green-yellow tunable luminescence and excellent biocompatibility. Cell experiments show that Se-CQDs can be up-taken by osteosarcoma U2OS cells and activate the mitochondrial apoptosis pathway triggered by increased reactive oxygen species. They can arrest the cell cycle at the G2/S phase and promote cellular apoptosis with reduced invasion and migration. Molecularly, Se-CQDs can down-regulate the expression of DNMT1 while up-regulating the expression of PTEN due to the decreased promoter methylation. Notably, Se-incorporated CQDs are more effective in inhibiting the proliferation, migration, and invasion of osteosarcoma than Se-free CQDs. It is feasible to use Se-CQDs as candidates for the potential application of early monitoring and treatment of osteosarcoma.

A Novel Oncogenic Role of Disulfidptosis-related Gene SLC7A11 in Anti-tumor Immunotherapy Response to Human Cancers

BACKGROUND

The protein Solute Carrier Family 7 Member 11 (SLC7A11) plays a pivotal role in cellular redox homeostasis by suppressing disulfidptosis, which restricts tumor growth. Yet, its relevance in prognosis, immunity, and cancer treatment efficacy is not well understood.

METHODS

We conducted a comprehensive analysis of the expression of SLC7A11 across 33 cancer types, employing datasets from public databases. Methods, such as Cox regression and survival analyses assessed its prognostic significance, while functional enrichment explored the biological processes tied to SLC7A11. The association between SLC7A11 expression, immune cell infiltration, and immune-related gene expression was also scrutinized.

RESULTS

Notably, SLC7A11 expression was more pronounced in cancerous compared to normal samples and correlated with higher tumor grades. Increased SLC7A11 expression was linked to poor outcomes, particularly in liver hepatocellular carcinoma (LIHC). This protein's expression also showcased significant relationships with diverse molecular and immune subtypes. Additionally, a prognostic nomogram was devised, integrating SLC7A11 expression and clinical variables. High SLC7A11 levels corresponded with cell growth and senescence pathways in various cancers and with lipid and cholesterol metabolism in LIHC. Furthermore, potential therapeutic compounds for LIHC with high SLC7A11 were identified. Real-time PCR (qPCR) and Western blot were conducted to explore the expression of SLC7A11 in tumor tissues and cancer cell lines.

CONCLUSION

In summation, this study emphasizes the prognostic and immunological importance of SLC7A11, spotlighting its potential as a therapeutic target in LIHC.

Effects and Mechanisms of Fisetin against Ischemia-reperfusion Injuries: A Systematic Review

BACKGROUND

Ischemia-reperfusion injury (IRI) is a well-known ailment that can disturb organ function.

OBJECTIVES

This systematic review study investigated fisetin's effects and possible mechanisms in attenuating myocardial, cerebral, renal, and hepatic IRIs.

METHODS

This systematic review included studies earlier than Sep 2023 by following the PRISMA statement 2020. After determining inclusion and exclusion criteria and related keywords, bibliographic databases, such as Cochrane Library, PubMed, Web of Science, Embase, and Scopus databases, were used to search the relevant studies. Studies were imported in End- Note X8, and the primary information was recorded in Excel.

RESULTS

Fisetin reduced reactive oxygen species (ROS) generation and upregulated antioxidant enzymes, such as superoxide dismutase (SOD), glutathione (GSH), catalase (CAT), and glutathione peroxidase (GPx), in ischemic tissues. Moreover, fisetin can attenuate oxidative stress by activating phosphoinositide-3-kinase-protein kinase B/Akt (PI3K/Akt) and nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathways. Fisetin has been indicated to prevent the activation of several pro-inflammatory signaling pathways, including NF-κB (Nuclear factor kappa-light-chain-enhancer of activated B cells) and MAPKs (Mitogen-activated protein kinases). It also inhibits the production of pro-inflammatory cytokines and enzymes like tumor necrosis factor-a (TNF-α), inducible-NO synthase (iNOS), cyclooxygenase-2 (COX-2), prostaglandin E2 (PGE2), interleukin-1β (IL-1β), IL-1, and IL-6. Fisetin attenuates IRI by improving mitochondrial function, anti-apoptotic effects, promoting autophagy, and preserving tissues from histological changes induced by IRIs.

CONCLUSION

Fisetin, by antioxidant, anti-inflammatory, mitochondrial protection, promoting autophagy, and anti-apoptotic properties, can reduce cell injury due to myocardial, cerebral renal, and hepatic IRIs without any significant side effects.

Role of Fisetin in Selected Malignant Neoplasms in Women

A promising therapeutic window and cost-effectiveness are just two of the potential advantages of using naturally derived drugs. Fisetin (3,3',4',7-tetrahydroxyflavone) is a natural flavonoid of the flavonol group, commonly found in fruit and vegetables. In recent years, fisetin has gained wide attention across the scientific community because of its broad spectrum of pharmacological properties, including cytotoxic activity against most abundant cancers. By stimulating or inhibiting selected molecular targets or biochemical processes, fisetin could affect the reduction of metastasis or cancer progression, which indicates its chemotherapeutic or chemopreventive role. In this review, we have summarized the results of studies on the anticancer effects of fisetin on selected female malignancies, both in in vitro and in vivo tests, i.e., breast, cervical, and ovarian cancer, published over the past two decades. Until now, no article dedicated exclusively to the action of fisetin on female malignancies has appeared. This review also describes a growing number of nanodelivery systems designed to improve the bioavailability and solubility of this natural compound. The reported low toxicity and activity of fisetin on cancer cells indicate its valuable potential, but large-scale clinical trials are urgently needed to assess real chemotherapeutic efficacy of this flavonoid.

The Effect of G. applanatum Crude Polysaccharide Extract on Proinflammatory Cytokines and Proapoptotic Caspases in HeLa Cell Line: An In Vitro Study

Polysaccharide extracts exhibit promise as potential anticancer agents. Among the fungi rich in polysaccharide content, G. applanatum stands out; however, its anticancer activity necessitates further investigation. This study aims to explore the impact of G. applanatum crude polysaccharide (GACP) extract by assessing its effects on cell viability, levels of proinflammatory cytokines such as TNF-α, IFN-γ, IL-2, and IL-12, and levels of proapoptotic markers including caspase-3 and caspase-9, as well as the percentages of necrosis and apoptosis in the HeLa cell line. Employing the HeLa cell line as a research model, four groups were studied: KN (media and DMSO), K+ (doxorubicin 10 μg/mL), P1 (G. applanatum extract 200 μg/mL), and P2 (G. applanatum extract 400 μg/mL). The G. applanatum extract was obtained via boiling distilled water. Anticancer activity was evaluated through the MTT test (3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazolium bromide) conducted over three treatment durations (24, 48, and 72 hours). Cytokine levels and caspase-3 and caspase-9 levels were assessed using the ELISA test. Cell apoptosis was determined using the Annexin V-PI biomarker and analyzed through flow cytometry. The MTT test exhibited optimal results at the 48-hour treatment mark. Cytokine level analysis revealed significant reductions in TNF-α, IFN-γ, IL-2, and IL-12 levels (p < 0.005). Concurrently, caspase-3 and caspase-9 levels exhibited substantial increases (p < 0.005). Flow cytometry highlighted the highest percentage of apoptosis in HeLa cells. In conclusion, G. applanatum's polysaccharide extract demonstrates potential as an anticancer and therapeutic agent for cancer treatment.

New Propargyloxy Derivatives of Galangin, Kaempferol and Fisetin-Synthesis, Spectroscopic Analysis and In Vitro Anticancer Activity on Head and Neck Cancer Cells

Head and neck cancer (HNC) therapy is limited; therefore, new solutions are increasingly being sought among flavonoids, which exhibit numerous biological properties, including potential anticancer activity. However, because they are mostly insoluble in water, are unstable and have low bioavailability, they are subjected to chemical modification to obtain new derivatives with better properties. This study aimed to synthesize and analyze new propargyloxy derivatives of galangin, kaempferol and fisetin, and to evaluate their anticancer activity against selected HNC cell lines. The obtained derivatives were assessed by spectroscopic analysis; next, their anticancer activity was evaluated using a flow cytometer and real-time cell analysis. The results showed that only the fisetin derivative was suitable for further analysis, due to the lack of crystal formation of the compound. The fisetin derivative statistically significantly increases the number of cells in the G2/M phase (p < 0.05) and increases cyclin B1 levels. A statistically significant increase in the number of apoptotic cells after being exposed to the tested compound was also observed (p < 0.05). The data indicate that the obtained fisetin derivative exhibits anticancer activity by affecting the cell cycle and increasing apoptosis in selected HNC lines, which suggests its potential use as a new medicinal agent in the future.

Biological effects and mechanisms of fisetin in cancer: a promising anti-cancer agent

Fisetin, a natural flavonoid, possesses numerous biological activities that have been extensively studied in various diseases. When it comes to cancer, fisetin exhibits a range of biological effects, such as suppressing cell growth, triggering programmed cell death, reducing the formation of new blood vessels, protecting against oxidative stress, and inhibiting cell migration. Moreover, fisetin has the ability to enhance the effectiveness of chemotherapy. The anticancer properties of fisetin can be attributed to a diverse array of molecules and signaling pathways, including vascular endothelial growth factor (VEGF), mitogen-activated protein kinase (MAPK), nuclear factor-kappa B (NF-κB), PI3K/Akt/mTOR, and Nrf2/HO-1. Consequently, fisetin holds promise as a therapeutic agent for anticancer treatment. In this review, we place emphasis on the biological functions and various molecular targets of fisetin in anticancer therapy.

Senolytic and senomorphic interventions to defy senescence-associated mitochondrial dysfunction

The accumulation of senescent cells in the aging individual is associated with an increase in the occurrence of age-associated pathologies that contribute to poor health, frailty, and mortality. The number and type of senescent cells is viewed as a contributor to the body's senescence burden. Cellular models of senescence are based on induction of senescence in cultured cells in the laboratory. One type of senescence is triggered by mitochondrial dysfunction. There are several indications that mitochondria defects contribute to body aging. Senotherapeutics, targeting senescent cells, have been shown to induce their lysis by means of senolytics, or repress expression of their secretome, by means of senomorphics, senostatics or gerosuppressors. An outline of the mechanism of action of various senotherapeutics targeting mitochondria and senescence-associated mitochondria dysfunction will be here addressed. The combination of geroprotective interventions together with senotherapeutics will help to strengthen mitochondrial energy metabolism, biogenesis and turnover, and lengthen the mitochondria healthspan, minimizing one of several molecular pathways contributing to the aging phenotype.

Kaempferol and Fisetin-Related Signaling Pathways Induce Apoptosis in Head and Neck Cancer Cells

Despite the relative effectiveness of standard cancer treatment strategies, head and neck cancer (HNC) is still considered one of the leading causes of mortality and morbidity. While selected bioactive compounds of plant origin reveal a pro-apoptotic effect, kaempferol and fisetin flavonols have been reported as potential anti-cancer agents against malignant neoplasms. To date, their exact role in signaling pathways of head and neck cancer cells is largely unknown. Based on the various methods of cytotoxicity testing, we elucidated that kaempferol and fisetin inhibit proliferation, reduce the capacity of cell migration, and induce apoptosis in SCC-9, SCC-25, and A-253 HNC cells in a dose-dependent manner in vitro (p < 0.05, fisetin IC₅₀ values of 38.85 µM, 62.34 µM, and 49.21 µM, and 45.03 µM, 49.90 µM, and 47.49 µM for kaempferol-SCC-9, SCC-25, and A-253, respectively). The obtained results showed that exposure to kaempferol and fisetin reduces Bcl-2 protein expression, simultaneously leading to the arrest in the G2/M and S phases of the cell cycle. Kaempferol and fisetin inhibit cell proliferation by interfering with the cell cycle, which is strongly associated with the induction of G2/M arrest, and induce apoptosis by activating caspase-3 and releasing cytochrome c in human HNC cells. In addition, investigating flavonols, by inhibiting anti-apoptotic proteins from the Bcl-2 family and damaging the mitochondrial transmembrane potential, increased the level of cytochrome c. While flavonols selectively induce apoptosis of head and neck cancer cells, they may support oncological therapy as promising agents. The discovery of new derivatives may be a breakthrough in the search for effective chemotherapeutic agents with less toxicity and thus fewer side effects.

Mitochondrial Aging and Senolytic Natural Products with Protective Potential

Living organisms do not disregard the laws of thermodynamics and must therefore consume energy for their survival. In this way, cellular energy exchanges, which aim above all at the production of ATP, a fundamental molecule used by the cell for its metabolisms, favor the formation of waste products that, if not properly disposed of, can contribute to cellular aging and damage. Numerous genes have been linked to aging, with some favoring it (gerontogenes) and others blocking it (longevity pathways). Animal model studies have shown that calorie restriction (CR) may promote longevity pathways, but given the difficult application of CR in humans, research is investigating the use of CR-mimetic substances capable of producing the same effect. These include some phytonutrients such as oleuropein, hydroxytyrosol, epigallo-catechin-gallate, fisetin, quercetin, and curcumin and minerals such as magnesium and selenium. Some of them also have senolytic effects, which promote the apoptosis of defective cells that accumulate over the years (senescent cells) and disrupt normal metabolism. In this article, we review the properties of these natural elements that can promote a longer and healthier life.

The Potential Role of Fisetin, a Flavonoid in Cancer Prevention and Treatment

Cancer is a main culprit and the second-leading cause of death worldwide. The current mode of treatment strategies including surgery with chemotherapy and radiation therapy may be effective, but cancer is still considered a major cause of death. Plant-derived products or their purified bioactive compounds have confirmed health-promoting effects as well as cancer-preventive effects. Among these products, flavonoids belong to polyphenols, chiefly found in fruits, vegetables and in various seeds/flowers. It has been considered to be an effective antioxidant, anti-inflammatory and to play a vital role in diseases management. Besides these activities, flavonoids have been revealed to possess anticancer potential through the modulation of various cell signaling molecules. In this regard, fisetin, a naturally occurring flavonoid, has a confirmed role in disease management through antioxidant, neuro-protective, anti-diabetic, hepato-protective and reno-protective potential. As well, its cancer-preventive effects have been confirmed via modulating various cell signaling pathways including inflammation, apoptosis, angiogenesis, growth factor, transcription factor and other cell signaling pathways. This review presents an overview of the anti-cancer potential of fisetin in different types of cancer through the modulation of cell signaling pathways based on in vivo and in vitro studies. A synergistic effect with anticancer drugs and strategies to improve the bioavailability are described. More clinical trials need to be performed to explore the anti-cancer potential and mechanism-of-action of fisetin and its optimum therapeutic dose.

Therapeutic targeting of mechanical stretch-induced FAK/ERK signaling by fisetin in hypertrophic scars

Hypertrophic scarring is a complex fibrotic disease with few treatment options. Mechanical stress has been proven to be crucial for hypertrophic scar (HS) formation. Here, we showed that the flavonoid small molecule fisetin, could dramatically ameliorate HS formation in a mechanical stretch-induced mouse model. In addition, in vitro and in vivo studies demonstrated that fisetin inhibited the stretch-induced profibrotic effects by suppressing the proliferation, activation, and collagen production of fibroblasts. Mechanistically, we revealed that fisetin obviously downregulated mechanical stretch-induced the phosphorylation of FAK and ERK, and reduced nuclear localization of ERK. This bioactivity of fisetin may result from its selective binding to the catalytic region of FAK, which was suggested by the molecular docking study and kinase binding assay. Taken together, these findings suggest that fisetin is a promising agent for the treatment of hypertrophic scars and other excessive fibrotic diseases.

Fisetin, a Potent Anticancer Flavonol Exhibiting Cytotoxic Activity against Neoplastic Malignant Cells and Cancerous Conditions: A Scoping, Comprehensive Review

Diet plays a crucial role in homeostasis maintenance. Plants and spices containing flavonoids have been widely used in traditional medicine for thousands of years. Flavonols present in our diet may prevent cancer initiation, promotion and progression by modulating important enzymes and receptors in signal transduction pathways related to proliferation, differentiation, apoptosis, inflammation, angiogenesis, metastasis and reversal of multidrug resistance. The anticancer activity of fisetin has been widely documented in numerous in vitro and in vivo studies. This review summarizes the worldwide, evidence-based research on the activity of fisetin toward various types of cancerous conditions, while describing the chemopreventive and therapeutic effects, molecular targets and mechanisms that contribute to the observed anticancer activity of fisetin. In addition, this review synthesized the results from preclinical studies on the use of fisetin as an anticancer agent. Based on the available literature, it might be suggested that fisetin has a bioactive potential to become a complementary drug in the prevention and treatment of cancerous conditions. However, more in-depth research is required to validate current data, so that this compound or its derivatives can enter the clinical trial phase.