Quercetin potentiates the chemosensitivity of MCF-7 breast cancer cells to 5-fluorouracil

5-Fluorouracil induces ferroptosis in breast cancer cells via targeting SLC7A11

Breast cancer (BC) is one of the major causes of cancer mortality worldwide among women. 5-Fluorouracil (5-FU) is a widely used chemotherapy drug to treat breast cancer, which is unclear that the mechanism of inhibiting BC. Ferroptosis is a mode of programmed cell death determined by iron-dependent lipid peroxidation. The aim of the study was to investigate whether ferroptosis is involved in 5-FU-induced BC cell injury. In the current study, we found that iron metabolism and SLC7A11/GPX4 signaling may play a key role in cell death of BC induced by 5-FU in vitro. In vitro experiments, we found that 5-FU exposure significantly increased the levels of iron and reactive oxygen species (ROS) in MCF-7 and MDA-MB-231 cells. Furthermore, ferrostatin-1, the ferroptosis inhibitor, inhibited cell death induced by 5-FU. Subsequent western blotting, qRT-PCR, and measurement of various kits, fluorescence staining as well as cellular thermal shift assay, confirmed the results that 5-FU induces ferroptosis by targeting SLC7A11 in BC cells. In conclusion, the results in our study reveals that 5-FU exposure leads to ferroptosis in BC cells via targeting inhibition of SLC7A11/GPX4 signaling pathway, which offers novel insight in pharmacodynamic effect and mechanism of 5-FU in therapeutic avenues of BC.

Quercetin Induces Apoptosis Through Downregulating P4HA2 and Inhibiting the PI3K/Akt/mTOR Axis in Hepatocellular Carcinoma Cells: An In Vitro Study

BACKGROUND

Quercetin is a natural product with multiple activities, which possesses a promising antitumor effect on malignancies. The involvement of proline 4-hydroxylase II (P4HA2) in collagen synthesis is crucial in the growth of tumor cells. Apoptosis is a programmed cell death requisite for the stability of the intracellular environment. However, the relationship between quercetin and cell apoptosis, as well as the impact of P4HA2 in this connection, has not yet been specified in hepatocellular carcinoma(HCC).

AIMS

The present study used HCC cells to investigate how quercetin regulates P4HA2 and influences cell proliferation and apoptosis.

METHODS AND RESULTS

The outcomes reveal that quercetin can impede the viability and growth of HCC cells and generate cell apoptosis in a dose-dependent manner. Additionally, quercetin prompts downregulation of P4HA2, leading to cell apoptosis in HCC cells, and knocking down P4HA2 can enhance this effect. Furthermore, we pretreated HCC cells with inhibitors (Z-VAD-FMK, LY294002) or activators (740Y-P) and found that the PI3K/Akt/mTOR pathway was occupied with quercetin-induced cell apoptosis.

CONCLUSION

This investigation reveals that quercetin compels apoptosis in HCC cells by diminishing P4HA2 and restraining the PI3K/Akt/mTOR axis.

Quercetin-loaded magnetic nanoparticles: a promising tool for antitumor treatment in human breast cancer cells

Quercetin (QUE) is a phytoestrogen with known antitumor properties; however, its hydrophobic nature and low bioavailability limit its efficacy as an anticancer drug. To address this, we explored loading QUE onto a non-toxic nanocarrier. This study focused on the biological activity of magnetic iron oxide nanoparticles coated with polyethylene glycol (MAG@PEG) loaded with QUE (MAG@PEG@QUE) in MCF-7 cells. The MAG@PEG nanosystem was synthesised using a hydrothermal method, and QUE was incorporated by adding an alcoholic solution of QUE to an aqueous dispersion of MAG@PEG. QUE incorporation was confirmed qualitatively by FTIR spectroscopy and quantitatively through UV-visible spectroscopy. Cytotoxicity studies showed that MAG@PEG@QUE, at a concentration equivalent to the half-maximal inhibitory concentration (IC50) of free QUE, significantly reduced cell proliferation and viability while increasing apoptosis. MCF-7 cells treated with MAG@PEG@QUE also displayed actin cytoskeleton alterations typical of apoptotic cells. Transmission electron microscopy revealed clusters of magnetic nanoparticles within cellular vesicles. Targeted delivery of these nanoparticles was achieved using a static magnetic field, leading to high intracellular accumulation and selective cell death in targeted areas, without affecting adjacent cells. In conclusion, MAG@PEG@QUE shows comparable antitumor effects to free QUE and has the potential to enhance QUE's bioavailability and targeted delivery for breast cancer treatment.

Quercetin Promote the Chemosensitivity in Organoids Derived from Patients with Breast Cancer

Aim

The study aimed to culture organoids from tissues of patients with breast cancer (BC) and use the organoids to measure the sensitivity to quercetin and its combination with chemotherapeutic agents.

Methods

Four patient-derived organoids (PDOs) of BC were cultured. The proliferative activity and morphology of PDOs were evaluated on different generations and after resuscitation. H&E and immunohistochemical (IHC) staining were used to identify the pathological changes and the expression of biomarkers. The sensitivity to quercetin and chemotherapeutic agents and their combinations were evaluated using adenosine triphosphate (ATP) viability assays.

Results

We successfully obtained all PDOs from BC tissues. PDOs preserved their activity and morphology during generation passage. In addition, the pathological changes and expression patterns of estrogen receptor (ER), human epidermal growth factor receptor (HER2), and Ki67 of each PDO were consistent with their original tissues. All four PDOs were highly sensitive to quercetin, and their IC50 values were less than 22 μM. PDOs showed better sensitivity to docetaxel and epirubicin hydrochloride, but less sensitivity to cis-platinum. Combination with quercetin promoted the sensitivity to three chemotherapeutic agents. In particular, the IC50 value of cis-platinum greatly decreased.

Conclusion

We successfully established PDOs from patients with BC and demonstrated that quercetin can promote the sensitivity of chemotherapeutic agents in these PDOs.

Quercetin Enhances 5-Fluorouracil-Driven Cytotoxicity Dose-Dependently in A375 Human Melanoma Cells

Cutaneous melanoma (CM) represents a severe skin cancer with a rising incidence at present and limited treatment options. 5-Fluorouracil (5-FU) is widely used, including for CM; however, the innate resistance of this cancer to conventional therapy remains problematic. Quercetin (QUE) is a flavonoid that can sensitize cancer cells to antitumor agents such as 5-FU. However, the potential sensitization capability of CM cells to 5-FU has scarcely been determined, and is investigated herein. Therefore, A375 CM cells were tested in terms of their cell viability, cell confluence, and morphological changes. Their nuclear and cytoskeletal aspects, clonogenic potential, and in ovo properties were also followed. The results showed that the 50% inhibitory concentrations (IC50s) of 5-FU and QUE determined by a cell proliferation assay were 11.56 and 11.08 µM, respectively. The addition of QUE (10 µM) to 5-FU (5-50 µM) increased the cytotoxic potential. A significant decline in cell viability (up to 43.51%), the loss of cell confluence, chromatin condensation and nuclear dysmorphology, tubulin and F-actin constriction, and a suppressed clonogenic ability were noted. The QUE + 5-FU association was non-irritating to the chorioallantoic membrane and showed an antiangiogenic effect in ovo. Thus, our results highlight that combining QUE with 5-FU can enhance the cytotoxic effect of 5-FU in A375 melanoma cells and present a safe profile in ovo.

From nature to clinic: Quercetin's role in breast cancer immunomodulation

Immunotherapy has brought hope to many breast cancer patients, but not all patients benefit from it. Quercetin (Qu), a natural product found in various sources, has anti-inflammatory and anti-tumor properties. We conducted a review of the pharmacological research of Qu in regulating anti-tumor immunity in vivo and in vitro. Qu can directly regulate the local tumor microenvironment (TME) by enhancing the activity of immune cells which includes promoting the infiltration of T cells and natural killer (NK) cells, inhibiting the recruitment of myeloid-derived suppressor cells and tumor-associated macrophages. Additionally, Qu inhibits anaerobic glycolysis in tumor cells, thereby reducing the production and transport of lactic acid. It also suppresses tumor angiogenesis by targeting the vascular endothelial growth factor (VEGF) pathway and the vitamin D pathway. Furthermore, Qu can enhance the efficacy of immunotherapy for breast cancer by modulating the systemic microenvironment. This includes inhibiting obesity-related chronic inflammation to decrease the production of inflammatory factors, regulating the composition of intestinal microbiota, and intervening in the metabolism of intestinal flora. At the same time, we also address challenges in the clinical application of Qu, such as low absorption rates and unknown effective doses. In conclusion, we highlight Qu as a natural immunomodulator that enhances immune cell activity and has the potential to be developed as an adjunct for breast cancer.

Double-Edged Sword Effect of Diet and Nutrition on Carcinogenic Molecular Pathways in Breast Cancer

Environmental exposure to a mixture of chemical xenobiotics acts as a double-edged sword, promoting or suppressing tumorigenesis and the development of breast cancer (BC). Before anything else, we are what we eat. In this review, we highlight both "the good" and "the bad" sides of the daily human diet and dietary patterns that could influence BC risk (BCR) and incidence. Thus, regularly eating new, diversified, colorful, clean, nutrient-rich, energy-boosting, and raw food, increases apoptosis and autophagy, antioxidation, cell cycle arrest, anti-inflammation, and the immune response against BC cells. Moreover, a healthy diet could lead to a reduction in or the inhibition of genomic instability, BC cell stemness, growth, proliferation, invasion, migration, and distant metastasis. We also emphasize that, in addition to beneficial compounds, our food is more and more contaminated by chemicals with harmful effects, which interact with each other and with endogenous proteins and lipids, resulting in synergistic or antagonistic effects. Thus, a healthy and diverse diet, combined with appropriate nutritional behaviors, can exert anti-carcinogenic effects and improve treatment efficacy, BC patient outcomes, and the overall quality of life of BC patients.

Co-delivery of temozolomide and quercetin with folic acid-conjugated exosomes in glioblastoma treatment

Aim: The study aims to improve glioblastoma multiforme (GBM) treatment by combining temozolomide (TMZ) and quercetin (Qct), using folic acid (FA)-conjugated exosomes to overcome TMZ resistance and enhance blood-brain barrier (BBB) penetration.Methods: Exosomes were isolated and after characterizing and modifying their surfaces with FA, drug loading of TMZ and Qct into exosomes was done. In vitro assays, including cell viability tests, RT-PCR, Western-blotting and flow-cytometry, were performed using U87MG and U251MG GBM cell lines. In vivo analysis included administering exosome-drug formulations to glioblastoma-bearing Wistar rats, monitored through optical imaging and PET scans, followed by post-mortem immunohistochemistry and histological examination.Results: The results showed successful exosome isolation and FA conjugation, with drug release studies indicating accelerated release of TMZ and Qct in acidic conditions, enhancing cytotoxicity. Immunofluorescence indicated greater exosome uptake in GBM cells due to FA conjugation. Cell viability assays demonstrated increased toxicity of the combination therapy, correlating with elevated apoptosis. In vivo studies revealed significant tumor size reduction, alongside increased apoptosis and reduced angiogenesis, particularly in the TMZ-Qct-Exo-FA group.Conclusion: FA-conjugated exosomes loaded with TMZ and Qct represent a promising strategy to enhance GBM treatment efficacy by improving drug delivery, apoptosis induction and inhibiting the PI3K/Akt/mTOR pathway.

Dietary interventions and tumor response to chemotherapy in breast cancer: A comprehensive review of preclinical and clinical data

BACKGROUND & AIMS

Optimizing treatment efficacy is still a critical part in advancing the treatment of breast cancer. Dietary interventions have drawn significant attention for their potential to increase tumor sensitivity, with a plethora of strategies evaluated both preclinically and clinically. The aim of this paper is to explore these strategies, ranging from entire dietary programs to specific supplements, for their potential to directly enhance tumor sensitivity and chemotherapy adherence.

METHODS

PubMed, Scopus, Embase and Web of Science databases were searched up to September 2023. In this comprehensive review, preclinical and clinical research on dietary interventions used in conjunction with chemotherapy for breast cancer was examined and synthesized, to identify potential causal mechanisms.

RESULTS

42 studies in total were identified and synthesized, 32 pre-clinical and 8 clinical studies.

CONCLUSION

Although a topic of intense interest, the heterogeneity in approaches has resulted in a large but minimally impactful evidence base, further complicated by a limited understanding of the mechanisms at play. This review highlights the areas for further research to increase opportunities for nutritional-based interventions as adjuvant to chemotherapy for breast cancer.

Safety Evaluation of Carbon Dots in UM-UC-5 and A549 Cells for Biomedical Applications

BACKGROUNG

The rising complexity and associated side effects of cancer treatments highlight the need for safer and more effective therapeutic agents. Carbon-based nanomaterials such as CDs have been gaining prominence for their unique characteristics, opening avenues for diverse applications such as fluorescence imaging, drug and gene transport, controlled drug delivery, medical diagnosis, and biosensing. Despite promising advancements in research, it remains imperative to scrutinize the properties and potential cytotoxicity of newly developed CDs, ensuring their viability for these applications.

METHODS

We synthesized four N-doped CDs through a hydrothermal method. Cell viability assays were conducted on A549 and UM-UC-5 cancer cells at a range of concentrations and incubation times, both individually and with the chemotherapeutic agent 5-fluorouracil (5-FU).

RESULTS

The obtained results suggest that the newly developed CDs exhibit suitability for applications such as bioimaging, as no significant impact on cell viability was observed for CDs alone.

Exploring the therapeutic potential of quercetin in cancer treatment: Targeting long non-coding RNAs

The escalating global incidence of cancer, which results in millions of fatalities annually, underscores the pressing need for effective pharmacological interventions across diverse cancer types. Long noncoding RNAs (lncRNAs), a class of RNA molecules that lack protein-coding capacity but profoundly impact gene expression regulation, have emerged as pivotal players in key cellular processes, including proliferation, apoptosis, metastasis, cellular metabolism, and drug resistance. Among natural compounds, quercetin, a phenolic compound abundantly present in fruits and vegetables has garnered attention due to its significant anticancer properties. Quercetin demonstrates the ability to inhibit cancer cell growth and induce apoptosis-a process often impaired in malignant cells. In this comprehensive review, we delve into the therapeutic potential of quercetin in cancer treatment, with a specific focus on its intricate interactions with lncRNAs. We explore how quercetin modulates lncRNA expression and function to exert its anticancer effects. Notably, quercetin suppresses oncogenic lncRNAs that drive cancer development and progression while enhancing tumor-suppressive lncRNAs that impede cancer growth and dissemination. Additionally, we discuss quercetin's role as a chemopreventive agent, which plays a crucial role in mitigating cancer risk. We address research challenges and future directions, emphasizing the necessity for in-depth mechanistic studies and strategies to enhance quercetin's bioavailability and target specificity. By synthesizing existing knowledge, this review underscores quercetin's promising potential as a novel therapeutic strategy in the ongoing battle against cancer, offering fresh insights and avenues for further investigation in this critical field.

Natural products and derivatives for breast cancer treatment: From drug discovery to molecular mechanism

BACKGROUND

Breast cancer stands as the most common malignancy among women globally and a leading cause of cancer-related mortality. Conventional treatments, such as surgery, hormone therapy, radiotherapy, chemotherapy, and small-molecule targeted therapy, often fall short of addressing the complexity and heterogeneity of certain breast cancer subtypes, leading to drug resistance and metastatic progression. Thus, the search for novel therapeutic targets and agents is imperative. Given their low toxicity and abundant variety, natural products and their derivatives are increasingly considered valuable sources for small-molecule anticancer drugs.

PURPOSE

This review aims to elucidate the pharmacological impacts and underlying mechanisms of active compounds found in select natural products and their derivatives, primarily focusing on breast cancer treatment. It intends to underscore the potential of these substances in combating breast cancer and guide future research directions for the development of natural product-based therapeutics.

METHODS

We conducted comprehensive searches in electronic databases such as PubMed, Web of Science, and Scopus until October 2023, using keywords such as 'breast cancer', 'natural products', 'derivatives', 'mechanism', 'signaling pathways', and various keyword combinations.

RESULTS

The review presents a spectrum of phytochemicals, including but not limited to flavonoids, polyphenols, and alkaloids, and examines their actions in various animal and cellular models of breast cancer. The anticancer effects of these natural products and derivatives are manifested through diverse mechanisms, including induction of cell death via apoptosis and autophagy, and suppression of tumor angiogenesis.

CONCLUSION

An increasing array of natural products and their derivatives are proving effective against breast cancer. Future therapeutic strategies can benefit from strategic enhancement of the anticancer properties of natural compounds, optimization for targeted action, improved bioavailability, and minimized side effects. The forthcoming research on natural products should prioritize these facets to maximize their therapeutic potential.

Anticancer Activity and Molecular Mechanisms of Acetylated and Methylated Quercetin in Human Breast Cancer Cells

Quercetin, a flavonoid polyphenol found in many plants, has garnered significant attention due to its potential cancer chemoprevention. Our previous studies have shown that acetyl modification of the hydroxyl group of quercetin altered its antitumor effects in HepG2 cells. However, the antitumor effect in other cancer cells with different gene mutants remains unknown. In this study, we investigated the antitumor effect of quercetin and its methylated derivative 3,3',4',7-O-tetramethylquercetin (4Me-Q) and acetylated derivative 3,3',4',7-O-tetraacetylquercetin (4Ac-Q) on two human breast cancer cells, MCF-7 (wt-p53, caspase-3-ve) and MDA-MB-231 (mt-p53, caspase-3+ve). The results demonstrated that 4Ac-Q exhibited significant cell proliferation inhibition and apoptosis induction in both MCF-7 and MDA-MB-231 cells. Conversely, methylation of quercetin was found to lose the activity. The human apoptosis antibody array revealed that 4Ac-Q might induce apoptosis in MCF-7 cells via a p53-dependent pathway, while in MDA-MB-231 cells, it was induced via a caspase-3-dependent pathway. Furthermore, an evaluation using a superoxide inhibitor, MnTBAP, revealed 4Ac-Q-induced apoptosis in MCF-7 cells in a superoxide-independent manner. These findings provide valuable insights into the potential of acetylated quercetin as a new approach in cancer chemoprevention and offer new avenues for health product development.

Effects of Functional and Nutraceutical Foods in the Context of the Mediterranean Diet in Patients Diagnosed with Breast Cancer

Several studies report that breast cancer survivors (BCS) tend to have a poor diet, as fruit, vegetable, and legume consumption is often reduced, resulting in a decreased intake of nutraceuticals. Moreover, weight gain has been commonly described among BCS during treatment, increasing recurrence rate and mortality. Improving lifestyle and nutrition after the diagnosis of BC may have important benefits on patients' general health and on specific clinical outcomes. The Mediterranean diet (MD), known for its multiple beneficial effects on health, can be considered a nutritional pool comprising several nutraceuticals: bioactive compounds and foods with anti-inflammatory and antioxidant effects. Recent scientific advances have led to the identification of nutraceuticals that could amplify the benefits of the MD and favorably influence gene expression in these patients. Nutraceuticals could have beneficial effects in the postdiagnostic phase of BC, including helping to mitigate the adverse effects of chemotherapy and radiotherapy. Moreover, the MD could be a valid and easy-to-follow option for managing excess weight. The aim of this narrative review is to evaluate the recent scientific literature on the possible beneficial effects of consuming functional and nutraceutical foods in the framework of MD in BCS.

Naringenin in combination with quercetin/fisetin shows synergistic anti-proliferative and migration reduction effects in breast cancer cell lines

INTRODUCTION & AIM

Breast cancer is one of the most common cancers with a high mortality rate among women worldwide. Quercetin/fisetin and naringenin, three well-known flavonoids, have been used to fight against various cancers. The aim of the present study was to investigate the possible synergism of quercetin/fisetin with naringenin on MCF7 and MDA-MB-231 breast cancer cell lines.

METHODS

In this study, cultured MCF7 and MDA-MB-231 cells were treated with different concentrations of quercetin/fisetin individually and in combination with naringenin. MTT assay and scratch assay was employed to determine cell viability and migration respectively. Real-time PCR was used to study the expression level of apoptosis genes and miR-1275 (tumor suppressor miRNA) and mir-27a-3p (oncogenic miRNA).

RESULTS

A synergism effect of quercetin/fisetin and naringenin (CI < 1) was observed for both cell lines. Combination therapies were significantly more effective in cell growth reduction, migration suppression and apoptosis induction than single therapies. Gene expression analysis revealed the upregulation of miR-1275 and downregulation miR-27a-3p.

CONCLUSION

Our results indicate that quercetin/fisetin enhances the anti-proliferative and anti-migratory activities in combination with naringenin in MCF7 and MDA-MB-231 human breast cancer cell lines. Therefore, the combination of Que/Fis and Nar can be proposed as a promising therapeutic strategy for further investigations.

Sinapic acid alleviates 5-fluorouracil-induced nephrotoxicity in rats via Nrf2/HO-1 signalling

Fluoropyrimidine 5-fluorouracil (5-FU) is a DNA analogue broadly used in chemotherapy, though treatment-associated nephrotoxicity limits its widespread clinical use. Sinapic acid (SA) has potent antioxidant, anti-inflammatory, and anti-apoptotic effects, we investigated its protective effects against 5-FU-induced nephrotoxicity in a rat model. We designated four treatment groups each Group I (control) received five intraperitoneal saline injections (once daily) from days 17 to 21; Group II received five intraperitoneal injections of 5-FU (50 mg/kg/day) from days 17 to 21; Group III received an oral administration of SA (40 mg/kg) for 21 days and five intraperitoneal injections of 5-FU (50 mg/kg/day) from days 17 to 21; and Group IV received an oral administration of SA (40 mg/kg) for 21 days (n-six rats in each group). blood samples were collected on day 22 from each group. Animals were sacrificed and their kidneys removed, and instantly frozen. 5-FU caused oxidative stress, inflammation, and activation of the apoptotic pathway by upregulating Bax and Caspase-3 and downregulating Bcl-2. However, SA exposure reduced serum toxicity indicators, boosted antioxidant defences, and reduced kidney apoptosis, which was confirmed by histopathological analysis. Therefore, prophylactic administration of SA could inhibit 5-FU-induced renal injuries in rats via suppression of renal inflammation and oxidative stress, primarily through regulation of NF-κB and proinflammatory cytokines, inhibition of renal apoptosis, and restoration of tubular epithelial antioxidant activities and cytoprotective defences.

Selected Flavonols in Breast and Gynecological Cancer: A Systematic Review

The consumption of foods that are rich in phenolic compounds has chemopreventive effects on many cancers, including breast cancer, ovarian cancer, and endometrial cancer. A wide spectrum of their health-promoting properties such as antioxidant, anti-inflammatory, and anticancer activities, has been demonstrated. This paper analyzes the mechanisms of the anticancer action of selected common flavonols, including kemferol, myricetin, quercetin, fisetin, galangin, isorhamnetin, and morin, in preclinical studies, with particular emphasis on in vitro studies in gynecological cancers and breast cancer. In the future, these compounds may find applications in the prevention and treatment of gynecological cancers and breast cancer, but this requires further, more advanced research.

Combination Chemotherapy with Selected Polyphenols in Preclinical and Clinical Studies-An Update Overview

This review article describes studies published over the past five years on the combination of polyphenols, which are the most studied in the field of anticancer effects (curcumin, quercetin, resveratrol, epigallocatechin gallate, and apigenin) and chemotherapeutics such as cisplatin, 5-fluorouracil, oxaliplatin, paclitaxel, etc. According to WHO data, research has been limited to five cancers with the highest morbidity rate (lung, colorectal, liver, gastric, and breast cancer). A systematic review of articles published in the past five years (from January 2018 to January 2023) was carried out with the help of all Web of Science databases and the available base of clinical studies. Based on the preclinical studies presented in this review, polyphenols can enhance drug efficacy and reduce chemoresistance through different molecular mechanisms. Considering the large number of studies, curcumin could be a molecule in future chemotherapy cocktails. One of the main problems in clinical research is related to the limited bioavailability of most polyphenols. The design of a new co-delivery system for drugs and polyphenols is essential for future clinical research. Some polyphenols work in synergy with chemotherapeutic drugs, but some polyphenols can act antagonistically, so caution is always required.

Towards dual function of autophagy in breast cancer: A potent regulator of tumor progression and therapy response

As a devastating disease, breast cancer has been responsible for decrease in life expectancy of females and its morbidity and mortality are high. Breast cancer is the most common tumor in females and its treatment has been based on employment of surgical resection, chemotherapy and radiotherapy. The changes in biological behavior of breast tumor relies on genomic and epigenetic mutations and depletions as well as dysregulation of molecular mechanisms that autophagy is among them. Autophagy function can be oncogenic in increasing tumorigenesis, and when it has pro-death function, it causes reduction in viability of tumor cells. The carcinogenic function of autophagy in breast tumor is an impediment towards effective therapy of patients, as it can cause drug resistance and radio-resistance. The important hallmarks of breast tumor such as glucose metabolism, proliferation, apoptosis and metastasis can be regulated by autophagy. Oncogenic autophagy can inhibit apoptosis, while it promotes stemness of breast tumor. Moreover, autophagy demonstrates interaction with tumor microenvironment components such as macrophages and its level can be regulated by anti-tumor compounds in breast tumor therapy. The reasons of considering autophagy in breast cancer therapy is its pleiotropic function, dual role (pro-survival and pro-death) and crosstalk with important molecular mechanisms such as apoptosis. Moreover, current review provides a pre-clinical and clinical evaluation of autophagy in breast tumor.

Targets Involved in the Anti-Cancer Activity of Quercetin in Breast, Colorectal and Liver Neoplasms

Phytochemicals have long been effective partners in the fight against several diseases, including cancer. Among these, flavonoids are valuable allies for both cancer prevention and therapy since they are known to influence a large panel of tumor-related processes. Particularly, it was revealed that quercetin, one of the most common flavonoids, controls apoptosis and inhibits migration and proliferation, events essential for the development of cancer. In this review, we collected the evidence on the anti-cancer activity of quercetin exploring the network of interactions between this flavonol and the proteins responsible for cancer onset and progression focusing on breast, colorectal and liver cancers, owing to their high worldwide incidence. Moreover, quercetin proved to be also a potentiating agent able to push further the anti-cancer activity of common employed anti-neoplastic agents, thus allowing to lower their dosages and, above all, to sensitize again resistant cancer cells. Finally, novel approaches to delivery systems can enhance quercetin's pharmacokinetics, thus boosting its great potentiality even further. Overall, quercetin has a lot of promise, given its multi-target potentiality; thus, more research is strongly encouraged to properly define its pharmaco-toxicological profile and evaluate its potential for usage in adjuvant and chemoprevention therapy.

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.

Synthesis, characterization, antioxidant and anticancer activities of a new Schiff base and its M(II) complexes derived from 5-fluorouracil

In this study, Schiff base ligand was obtained from the condensation reaction of benzene-1,2-diamine and 5-fluoropyrimidine-2,4(1H,3H)-dione (5-FU). Metal(II) complexes were synthesized with Fe(II), Co(II) and Ni(II) chloride salts. The synthesized ligand and metal complexes were characterized by FT-IR, UV-vis, ¹H-¹³C NMR, elemental analyses, mass spectroscopy, magnetic moments, molar conductivity and thermogravimetric analysis studies. With the help of different techniques reveal Fe(II), Co(II) and Ni(II) complexes have exhibited tetrahedral and octahedral geometry. Ligand acted as bidentate and it binds metal(II) ions through deprotonated-NH, imine-N atom and carbonyl-O atom, respectively. DPPH, ABTS, FRAP, CUPRAC and total antioxidant activity methods were used to determine the antioxidant properties of ligand and metal complexes. According to the results, the synthesized compounds showed very high antioxidant activity compared to 5-FU. The cytotoxicities of the synthesized compounds were performed on MCF-7 (human breast cancer) and L-929 (fibroblast) cell lines using the MTT assay. In addition, the effect of electroporation (EP) on the cytotoxicity of the compounds was investigated. Our results demonstrated that novel Co(II) and Ni(II) complexes show potential as new anticancer agents and ECT may be a viable treatment option for breast cancer.

Nanogold Particles Suppresses 5-Flurouracil-Induced Renal Injury: An Insight into the Modulation of Nrf-2 and Its Downstream Targets, HO-1 and γ-GCS

The development of the field of nanotechnology has revolutionized various aspects in the fields of modern sciences. Nano-medicine is one of the primary fields for the application of nanotechnology techniques. The current study sheds light on the reno-protective impacts of gold nano-particles; nanogold (AuNPs) against 5-flurouracil (5-FU)-induced renal toxicity. Indeed, the use of 5-FU has been associated with kidney injury which greatly curbs its therapeutic application. In the current study, 5-FU injection was associated with a significant escalation in the indices of renal injury, i.e., creatinine and urea. Alongside this, histopathological and ultra-histopathological changes confirmed the onset of renal injury. Both gene and/or protein expression of nuclear factor erythroid 2-related factor 2 (Nrf-2) and downstream antioxidant enzymes revealed consistent paralleled anomalies. AuNPs administration induced a significant renal protection on functional, biochemical, and structural levels. Renal expression of the major sensor of the cellular oxidative status Nrf-2 escalated with a paralleled reduction in the renal expression of the other contributor to this axis, known as Kelch-like ECH-associated protein 1 (Keap-1). On the level of the effector downstream targets, heme oxygenase 1 (HO-1) and gamma-glutamylcysteine synthetase (γ-GCS) AuNPs significantly restored their gene and protein expression. Additionally, combination of AuNPs with 5-FU showed better cytotoxic effect on MCF-7 cells compared to monotreatments. Thus, it can be inferred that AuNPs conferred reno-protective impact against 5-FU with an evident modulatory impact on Nrf-2/Keap-1 and its downstream effectors, HO-1 and γ-GCS, suggesting its potential use in 5-FU regimens to improve its therapeutic outcomes and minimize its underlying nephrotoxicity.