Quercetin Suppresses CYR61-Mediated Multidrug Resistance in Human Gastric Adenocarcinoma AGS Cells

Exploration of the sensitization effect of Chaihu Shugan powder on chemotherapy for triple-negative breast cancer and its active ingredients

Chemotherapy plays a crucial role in the clinical treatment of triple-negative breast cancer (TNBC), but drug resistance limits its clinical application. The active ingredients of Chaihu Shugan Powder (CSP; Bupleurum Liver-Coursing Powder), quercetin and luteolin, both belong to flavonoid compounds and have significant anti-tumor potential, which can promote chemotherapy sensitivity. However, the correlation between the two and TNBC paclitaxel (PTX) chemotherapy sensitivity is unknown. We collected herbal components of CSP from the TCMSP database, and screened effective molecules and corresponding targets. STRING database was utilized to construct a protein-protein interaction network combining effective molecules and target genes. The top 50 nodes ranked by affinity were chosen for subsequent functional analysis, and the drug-active ingredient-gene interaction network was established using Cytoscape software. Molecular docking was used to determine the small molecules that target TNBC PTX resistance. The "clusterProfiler" package was utilized for GO and KEGG enrichment analyses on the top 50 genes to determine the pathways affected by CSP. Cell counting and colony formation assays evaluated cell viability, IC50 values, and proliferation capacity. Flow cytometry tested PTX intracellular accumulation. Western blot assayed the expression of TNF pathway-related proteins. Active ingredients of CSP, quercetin and luteolin, could inhibit TNBC cell proliferation and promote PTX chemotherapy sensitization. Quercetin and luteolin repressed the TNF signaling pathway and promoted PTX chemotherapy sensitization. Quercetin and luteolin could inhibit TNBC cell proliferation and promote PTX chemotherapy sensitization through the TNF signaling pathway. Therefore, the use of quercetin and luteolin plus PTX treatment provides a prospective strategy for TNBC treatment.

Harnessing the Power of Polyphenols: A New Frontier in Disease Prevention and Therapy

There are a wide variety of phytochemicals collectively known as polyphenols. Their structural diversity results in a broad range of characteristics and biological effects. Polyphenols can be found in a variety of foods and drinks, including fruits, cereals, tea, and coffee. Studies both in vitro and in vivo, as well as clinical trials, have shown that they possess potent antioxidant activities, numerous therapeutic effects, and health advantages. Dietary polyphenols have demonstrated the potential to prevent many health problems, including obesity, atherosclerosis, high blood sugar, diabetes, hypertension, cancer, and neurological diseases. In this paper, the protective effects of polyphenols and the mechanisms behind them are investigated in detail, citing the most recent available literature. This review aims to provide a comprehensive overview of the current knowledge on the role of polyphenols in preventing and managing chronic diseases. The cited publications are derived from in vitro, in vivo, and human-based studies and clinical trials. A more complete understanding of these naturally occurring metabolites will pave the way for the development of novel polyphenol-rich diet and drug development programs. This, in turn, provides further evidence of their health benefits.

Natural products for combating multidrug resistance in cancer

Cancer cells frequently develop resistance to chemotherapeutic therapies and targeted drugs, which has been a significant challenge in cancer management. With the growing advances in technologies in isolation and identification of natural products, the potential of natural products in combating cancer multidrug resistance has received substantial attention. Importantly, natural products can impact multiple targets, which can be valuable in overcoming drug resistance from different perspectives. In the current review, we will describe the well-established mechanisms underlying multidrug resistance, and introduce natural products that could target these multidrug resistant mechanisms. Specifically, we will discuss natural compounds such as curcumin, resveratrol, baicalein, chrysin and more, and their potential roles in combating multidrug resistance. This review article aims to provide a systematic summary of recent advances of natural products in combating cancer drug resistance, and will provide rationales for novel drug discovery.

Synergistic effects of flavonoids and paclitaxel in cancer treatment: a systematic review

Paclitaxel is a natural anticancer compound with minimal toxicity, the capacity to stabilize microtubules, and high efficiency that has remained the standard of treatment alongside platinum-based therapy as a remedy for a variety of different malignancies. In contrast, polyphenols such as flavonoids are also efficient antioxidant and anti-inflammatory and have now been shown to possess potent anticancer properties. Therefore, the synergistic effects of paclitaxel and flavonoids against cancer will be of interest. In this review, we use a Boolean query to comprehensively search the well-known Scopus database for literature research taking the advantage of paclitaxel and flavonoids simultaneously while treating various types of cancer. After retrieving and reviewing the intended investigations based on the input keywords, the anticancer mechanisms of flavonoids and paclitaxel and their synergistic effects on different targets raging from cell lines to animal models are discussed in terms of the corresponding involved signaling transduction. Most studies demonstrated that these signaling pathways will induce apoptotic / pro-apoptotic proteins, which in turn may activate several caspases leading to apoptosis. Finally, it can be concluded that the results of this review may be beneficial in serving as a theoretical foundation and reference for future studies of paclitaxel synthesis, anticancer processes, and clinical applications involving different clinical trials.

The mechanism of dehydroandrographolide inhibiting metastasis in gastric cancer based on network pharmacology and bioinformatics

Gastric cancer (GC) is the most aggressive malignant tumor of the digestive tract. However, there is still a lack of effective treatment methods in clinical practice. Studies have shown that dehydroandrographolide (DA) has been shown to have anti-cancer activity in a variety of cancers, but it has not been reported in GC. Firstly, we obtained data on DA target genes, GC-related genes, and differentially expressed genes (DEGs) from the PharmMapper, GeneCards, and GEO databases, respectively. Then, the STRING database was used to construct the protein-protein interaction network of intersection genes, and Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses of intersection genes were performed. Finally, 8 hub target genes were identified by analyzing their expression and prognostic survival, and molecular docking between the hub genes and DA was performed. In this study, 293 DA drug target genes, 11,366 GC-related genes, and 3184 DEGs were identified. Gene Ontology and KEGG analysis showed that the intersection genes of DA targets and GC-related genes were mainly related to cancer pathways involving apoptosis and cell adhesion. The intersection genes of DEGs, DA targets, and GC-related genes were also mainly related to cancer pathways involving chemical carcinogenesis, and drug metabolism. The molecular docking results showed that the 8 hub target genes had an apparent affinity for DA, which could be used as potential targets for DA treatment of GC. The results of this study show that the molecular mechanism by which DA inhibits GC metastasis involves multiple target genes. It may play an essential role in inhibiting the invasion and metastasis of GC by regulating the expression and polymorphism of hub target genes, such as MMP9, MMP12, CTSB, ESRRG, GSTA1, ADHIC, CA2, and AKR1C2.

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.

Mechanism of epithelial-mesenchymal transition in cancer and its regulation by natural compounds

Epithelial-mesenchymal transition (EMT) is a complex process with a primordial role in cellular transformation whereby an epithelial cell transforms and acquires a mesenchymal phenotype. This transformation plays a pivotal role in tumor progression and self-renewal, and exacerbates resistance to apoptosis and chemotherapy. EMT can be initiated and promoted by deregulated oncogenic signaling pathways, hypoxia, and cells in the tumor microenvironment, resulting in a loss-of-epithelial cell polarity, cell-cell adhesion, and enhanced invasive/migratory properties. Numerous transcriptional regulators, such as Snail, Slug, Twist, and ZEB1/ZEB2 induce EMT through the downregulation of epithelial markers and gain-of-expression of the mesenchymal markers. Additionally, signaling cascades such as Wnt/β-catenin, Notch, Sonic hedgehog, nuclear factor kappa B, receptor tyrosine kinases, PI3K/AKT/mTOR, Hippo, and transforming growth factor-β pathways regulate EMT whereas they are often deregulated in cancers leading to aberrant EMT. Furthermore, noncoding RNAs, tumor-derived exosomes, and epigenetic alterations are also involved in the modulation of EMT. Therefore, the regulation of EMT is a vital strategy to control the aggressive metastatic characteristics of tumor cells. Despite the vast amount of preclinical data on EMT in cancer progression, there is a lack of clinical translation at the therapeutic level. In this review, we have discussed thoroughly the role of the aforementioned transcription factors, noncoding RNAs (microRNAs, long noncoding RNA, circular RNA), signaling pathways, epigenetic modifications, and tumor-derived exosomes in the regulation of EMT in cancers. We have also emphasized the contribution of EMT to drug resistance and possible therapeutic interventions using plant-derived natural products, their semi-synthetic derivatives, and nano-formulations that are described as promising EMT blockers.

Anticancer applications of phytochemicals in gastric cancer: Effects and molecular mechanism

Gastric cancer (GC) is the fourth most common malignant cancer and is a life-threatening disease worldwide. Phytochemicals have been shown to be a rational, safe, non-toxic, and very promising approach to the prevention and treatment of cancer. It has been found that phytochemicals have protective effects against GC through inhibiting cell proliferation, inducing apoptosis and autophagy, suppressing cell invasion and migration, anti-angiogenesis, inhibit Helicobacter pylori infection, regulating the microenvironment. In recent years, the role of phytochemicals in the occurrence, development, drug resistance and prognosis of GC has attracted more and more attention. In order to better understand the relationship between phytochemicals and gastric cancer, we briefly summarize the roles and functions of phytochemicals in GC tumorigenesis, development and prognosis. This review will probably help guide the public to prevent the occurrence and development of GC through phytochemicals, and develop functional foods or drugs for the prevention and treatment of gastric cancer.

Dual role of quercetin in enhancing the efficacy of cisplatin in chemotherapy and protection against its side effects: a review

Chemotherapy has opened a new window in cancer therapy. However, the resistance of cancer cells has dramatically reduced the efficacy of chemotherapy. Cisplatin is a chemotherapeutic agent and its potential in cancer therapy has been restricted by resistance of cancer cells. As a consequence, the scientists have attempted to find new strategies in elevating chemotherapy efficacy. Due to great anti-tumour activity, naturally occurring compounds are of interest in polychemotherapy. Quercetin is a flavonoid with high anti-tumour activity against different cancers that can be used with cisplatin to enhance its efficacy and also are seen to sensitise cancer cells into chemotherapy. Furthermore, cisplatin has side effects such as nephrotoxicity and ototoxicity. Administration of quercetin is advantageous in reducing the adverse effects of cisplatin without compromising its anti-tumour activity. In this review, we investigate the dual role of quercetin in enhancing anti-tumour activity of cisplatin and simultaneous reduction in its adverse effects.

Telomerase inhibitor MST-312 and quercetin synergistically inhibit cancer cell proliferation by promoting DNA damage

Quercetin is a natural flavonoid with well-established anti-proliferative activities against a variety of cancers. Telomerase inhibitor MST-312 also exhibits anti-proliferative effect on various cancer cells independent of its effect on telomere shortening. However, due to their low absorption and toxicity at higher doses, their clinical development is limited. In the present study, we examine the synergistic potential of their combination in cancer cells, which may result in a decrease in the therapeutic dosage of these compounds. We report that MST-312 and quercetin exhibit strong synergism in ovarian cancer cells with combination index range from 0.2 to 0.7. Co-treatment with MST-312 and quercetin upregulates the DNA damage and augments apoptosis when compared to treatment with either compound alone or a vehicle. We also examined the effect of these compounds on the proliferation of normal ovarian surface epithelial cells (OSEs). MST-312 has a cytoprotective impact in OSEs at lower dosages, but is inhibitory at higher doses. Quercetin did not affect the OSEs proliferation at low concentrations while at higher concentrations it is inhibitory. Notably, combination of MST-312 and quercetin had no discernible impact on OSEs. These observations have significant implications for future efforts towards maximizing efficacy in cancer therapeutics as this co-treatment specifically affects cancer cells and reduces the effective dosage of both the compounds.

Single-cell RNA-seq recognized the initiator of epithelial ovarian cancer recurrence

Epithelial ovarian cancers (EOCs) are sensitive to chemotherapy but will ultimately relapse and develop drug resistance. The origin of EOC recurrence has been elusive due to intra-tumor heterogeneity. Here we performed single-cell RNA sequencing (scRNA-seq) in 13,369 cells from primary, untreated peritoneal metastasis, and relapse tumors. We used time-resolved analysis to chart the developmental sequence of cells from the metastatic tumors, then traced the earliest replanting cells back to the primary tumors. We discovered seven distinct subpopulations in primary tumors where the CYR61⁺ "stress" subpopulation was identified as the relapse-initiators. Furthermore, a subpopulation of RGS5⁺ cancer-associated fibroblasts (CAFs) was found to strongly support tumor metastasis. The combined CYR61/RGS5 expression scores significantly correlated with the relapse-free-survival of EOC patients and can be used as predictors of EOC recurrence. Our study provides insights into the mechanism of EOC recurrence and presents CYR61⁺ relapse-initiating cells as potential therapeutic targets to prevent EOC relapse.

Current Advances and Outlook in Gastric Cancer Chemoresistance: A Review

BACKGROUND

Surgical resection of the lesion is the standard primary treatment of gastric cancer. Unfortunately, most patients are already in the advanced stage of the disease when they are diagnosed with gastric cancer. Alternative therapies, such as radiation therapy and chemotherapy, can achieve only very limited benefits. The emergence of cancer drug resistance has always been the major obstacle to the cure of tumors. The main goal of modern cancer pharmacology is to determine the underlying mechanism of anticancer drugs.

OBJECTIVE

Here, we mainly review the latest research results related to the mechanism of chemotherapy resistance in gastric cancer, the application of natural products in overcoming the chemotherapy resistance of gastric cancer, and the new strategies currently being developed to treat tumors based on immunotherapy and gene therapy.

CONCLUSION

The emergence of cancer drug resistance is the main obstacle in achieving alleviation and final cure for gastric cancer. Mixed therapies are considered to be a possible way to overcome chemoresistance. Natural products are the main resource for discovering new drugs specific for treating chemoresistance, and further research is needed to clarify the mechanism of natural product activity in patients. .

Polyphenols as adjunctive treatments in psychiatric and neurodegenerative disorders: Efficacy, mechanisms of action, and factors influencing inter-individual response

The pathophysiology of psychiatric and neurodegenerative disorders is complex and multifactorial. Polyphenols possess a range of potentially beneficial mechanisms of action that relate to the implicated pathways in psychiatric and neurodegenerative disorders. The aim of this review is to highlight the emerging clinical trial and preclinical efficacy data regarding the role of polyphenols in mental and brain health, elucidate novel mechanisms of action including the gut microbiome and gene expression, and discuss the factors that may be responsible for the mixed clinical results; namely, the role of interindividual differences in treatment response and the potentially pro-oxidant effects of some polyphenols. Further clarification as part of larger, well conducted randomized controlled trials that incorporate precision medicine methods are required to inform clinical efficacy and optimal dosing regimens.

Ampelopsin Suppresses Stem Cell Properties Accompanied by Attenuation of Oxidative Phosphorylation in Chemo- and Radio-Resistant MDA-MB-231 Breast Cancer Cells

Ampelopsin, also known as dihydromyricetin, is a commonly found flavonoid in medicinal plants. The cancer stem cell (CSC) population is a promising target for triple-negative breast cancer (TNBC). In this study, flavonoid screening was performed in the established MDA-MB-231/IR cell line, which is enriched in CSCs. Ampelopsin suppressed the proliferation and colony formation of stem cell-rich MDA-MB-231/IR, while inducing their apoptosis. Importantly, ampelopsin displayed an inhibitory impact on the stemness features of MDA-MB-231/IR cells, demonstrated by decreases in mammosphere formation, the CD44⁺/CD24^-/low population, aldehyde dehydrogenase activity, and the levels of stem cell markers (e.g., CD44, MRP1, β-catenin, and KLF4). Ampelopsin also suppressed the epithelial-mesenchymal transition, as evidenced by decreases in migration, invasion capacity, and mesenchymal markers, as well as an increase in the epithelial marker E-cadherin. Moreover, ampelopsin significantly impaired oxidative phosphorylation by reducing the oxygen consumption rate and adenosine triphosphate production in MDA-MB-231/IR cells. Notably, ampelopsin treatment significantly reduced the levels of the phosphorylated forms of IκBα and NF-κB p65, as well as the levels of tumor necrosis factor (TNF)-α-stimulated phosphorylation of IκBα and NF-κB p65. These results demonstrated that ampelopsin prevents the TNF-α/NF-κB signaling axis in breast CSCs.

Effect of Quercetin on ABCC6 Transporter: Implication in HepG2 Migration

Quercetin is a member of the flavonoid group of compounds, which is abundantly present in various dietary sources. It has excellent antioxidant properties and anti-inflammatory activity and is very effective as an anti-cancer agent against various types of tumors, both in vivo and in vitro. Quercetin has been also reported to modulate the activity of some members of the multidrug-resistance transporters family, such as P-gp, ABCC1, ABCC2, and ABCG2, and the activity of ecto-5′-nucleotidase (NT5E/CD73), a key regulator in some tumor processes such as invasion, migration, and metastasis. In this study, we investigated the effect of Quercetin on ABCC6 expression in HepG2 cells. ABCC6 is a member of the superfamily of ATP-binding cassette (ABC) transporters, poorly involved in drug resistance, whose mutations cause pseudoxanthoma elasticum, an inherited disease characterized by ectopic calcification of soft connective tissues. Recently, it has been reported that ABCC6 contributes to cytoskeleton rearrangements and HepG2 cell motility through purinergic signaling. Gene and protein expression were evaluated by quantitative Reverse-Transcription PCR (RT-qPCR) and western blot, respectively. Actin cytoskeleton dynamics was evaluated by laser confocal microscopy using fluorophore-conjugated phalloidin. Cell motility was analyzed by an in vitro wound-healing migration assay. We propose that ABCC6 expression may be controlled by the AKT pathway as part of an adaptative response to oxidative stress, which can be mitigated by the use of Quercetin-like flavonoids.

Circulating Tumour Cells as Prognostic Biomarkers in Colorectal Cancer: A Systematic Review

Despite therapeutic advances, colorectal cancer (CRC) is still one of the deadliest cancers, partly due to local recurrence and metastatic disease. Tumour cells that spread by gaining access to peripheral blood are called circulating tumour cells (CTCs). These may be present before there are any clinical signs, but can be detected within blood samples. CTCs from patients with CRC may be isolated in a laboratory for characterization and multiple analyses. In this review, we focus on the prognostic potential of CTCs detection, by evaluating the reported progress and applications of such analyses. Our search found 77 relevant studies that reported CTC detection in CRC. Both cell count and features were reported as promising prognosis biomarkers. Since CTCs are rare and can lose their differentiation, new tools are being developed to improve detection. CTCs may have potential as prognostic biomarkers for CRC in terms of survival prediction, anticipating chemotherapy resistance, and surgical planning. CTCs are not yet used in clinical practice, and further investigations are required in order to better frame their practical value.

Effect of Quercetin on ABCC6 Transporter: Implication in HepG2 Migration

Quercetin is a member of the flavonoid group of compounds, which is abundantly present in various dietary sources. It has excellent antioxidant properties and anti-inflammatory activity and is very effective as an anti-cancer agent against various types of tumors, both in vivo and in vitro. Quercetin has been also reported to modulate the activity of some members of the multidrug-resistance transporters family, such as P-gp, ABCC1, ABCC2, and ABCG2, and the activity of ecto-5′-nucleotidase (NT5E/CD73), a key regulator in some tumor processes such as invasion, migration, and metastasis. In this study, we investigated the effect of Quercetin on ABCC6 expression in HepG2 cells. ABCC6 is a member of the superfamily of ATP-binding cassette (ABC) transporters, poorly involved in drug resistance, whose mutations cause pseudoxanthoma elasticum, an inherited disease characterized by ectopic calcification of soft connective tissues. Recently, it has been reported that ABCC6 contributes to cytoskeleton rearrangements and HepG2 cell motility through purinergic signaling. Gene and protein expression were evaluated by quantitative Reverse-Transcription PCR (RT-qPCR) and western blot, respectively. Actin cytoskeleton dynamics was evaluated by laser confocal microscopy using fluorophore-conjugated phalloidin. Cell motility was analyzed by an in vitro wound-healing migration assay. We propose that ABCC6 expression may be controlled by the AKT pathway as part of an adaptative response to oxidative stress, which can be mitigated by the use of Quercetin-like flavonoids.

Chondroitin sulfate-based nanoparticles for enhanced chemo-photodynamic therapy overcoming multidrug resistance and lung metastasis of breast cancer

As a major therapeutic approach for cancer treatment, the effectiveness of chemotherapy is challenged by multidrug resistance (MDR). Herein, we fabricated novel redox-responsive, chondroitin sulfate-based nanoparticles that could simultaneously deliver quercetin (chemosensitizer), chlorin e6 (photosensitizer) and paclitaxel (chemotherapeutic agent) to exert enhanced chemo-photodynamic therapy for overcoming MDR and lung metastasis of breast cancer. In vitro cell study showed that nanoparticles down-regulated the expression of P-glycolprotein (P-gp) on MCF-7/ADR cells and thereby improved the anticancer efficacy of PTX against MCF-7/ADR cells. Moreover, NIR laser irradiation could induce nanoparticles to generate cellular reactive oxygen species (ROS), leading to mitochondrial membrane potential loss, and meanwhile facilitating lysosomal escape of drugs. Importantly, the novel nanoplatform exhibited effective in vivo MDR inhibition and anti-metastasis efficacy through enhanced chemo-photodynamic therapy. Thus, the study suggested that the multifunctional nanoplatform had good application prospect for effective breast cancer therapy.

Potentially Bioaccessible Phenolics from Mung Bean and Adzuki Bean Sprouts Enriched with Probiotic-Antioxidant Properties and Effect on the Motility and Survival of AGS Human Gastric Carcinoma Cells

Gastric digests from mung (MBS) and adzuki (ABS) bean sprouts enriched with probiotic Lactobacillus plantarum 299v were tested for their antioxidant potential, as well as antiproliferative and antimotility properties, in human stomach cancer cells (AGS). The digest of ABS contained quercetin and kaempferol derivates, while kaempferol and apigenin derivates were dominant in MBS. Compared to the controls, the probiotic-rich sprouts had a higher antioxidant potential—by 13% and 9%, respectively. Adzuki bean sprouts decreased the viability of AGS already at low concentrations (25% motility inhibitions). MBS and ABS displayed dose-independent cytostatic effects. The ABS extracts decreased the proliferation of AGS more effectively than the MBS extracts—0.2‰ ABS exerted c.a. 70% of inhibitions. Moreover, the phytochemicals from the probiotic-rich sprouts considerably reduced this activity. The increased vinculin level, the apoptotic shape of cell nuclei, and the reduced cell motility and proliferation indicate that the extracts exhibited cytostatic and cytotoxic activity.

Defying Multidrug Resistance! Modulation of Related Transporters by Flavonoids and Flavonolignans

Multidrug resistance (MDR) is a major challenge for the 21th century in both cancer chemotherapy and antibiotic treatment of bacterial infections. Efflux pumps and transport proteins play an important role in MDR. Compounds displaying inhibitory activity toward these proteins are prospective for adjuvant treatment of such conditions. Natural low-cost and nontoxic flavonoids, thanks to their vast structural diversity, offer a great pool of lead structures with broad possibility of chemical derivatizations. Various flavonoids were found to reverse both antineoplastic and bacterial multidrug resistance by inhibiting Adenosine triphosphate Binding Cassette (ABC)-transporters (human P-glycoprotein, multidrug resistance-associated protein MRP-1, breast cancer resistance protein, and bacterial ABC transporters), as well as other bacterial drug efflux pumps: major facilitator superfamily (MFS), multidrug and toxic compound extrusion (MATE), small multidrug resistance (SMR) and resistance-nodulation-cell-division (RND) transporters, and glucose transporters. Flavonoids and particularly flavonolignans are therefore highly prospective compounds for defying multidrug resistance.

Phenethyl Isothiocyanate Suppresses Stemness in the Chemo- and Radio-Resistant Triple-Negative Breast Cancer Cell Line MDA-MB-231/IR Via Downregulation of Metadherin

Resistance to chemotherapy and radiation therapy is considered a major therapeutic barrier in breast cancer. Cancer stem cells (CSCs) play a prominent role in chemo and radiotherapy resistance. The established chemo and radio-resistant triple-negative breast cancer (TNBC) cell line MDA-MB-231/IR displays greater CSC characteristics than the parental MDA-MB-231 cells. Escalating evidence demonstrates that metadherin (MTDH) is associated with a number of cancer signaling pathways as well as breast cancer therapy resistance, making it an attractive therapeutic target. Kaplan–Meier plot analysis revealed a correlation between higher levels of MTDH and shorter lifetimes in breast cancer and TNBC patients. Moreover, there was a positive correlation between the MTDH and CD44 expression levels in The Cancer Genome Atlas breast cancer database. We demonstrate that MTDH plays a pivotal role in the regulation of stemness in MDA-MB-231/IR cells. Knockdown of MTDH in MDA-MB-231/IR cells resulted in a reduction in the CSC population, aldehyde dehydrogenase activity, and major CSC markers, including β-catenin, CD44⁺, and Slug. In addition, MTDH knockdown increased reactive oxygen species (ROS) levels in MDA-MB-231/IR cells. We found that phenethyl isothiocyanate (PEITC), a well-known pro-oxidant phytochemical, suppressed stemness in MDA-MB-231/IR cells through ROS modulation via the downregulation of MTDH. Co-treatment of PEITC and N-Acetylcysteine (a ROS scavenger) caused alterations in PEITC induced cell death and CSC markers. Moreover, PEITC regulated MTDH expression at the post-transcriptional level, which was confirmed using cycloheximide, a protein synthesis inhibitor.

Methanol Extract of Aerial Parts of Pavetta indica L. Enhances the Cytotoxic Effect of Doxorubicin and Induces Radiation Sensitization in MDA-MB-231 Triple-Negative Breast Cancer Cells

Pavetta indica L. is used in traditional medicine for the treatment of various diseases including hemorrhoids, headache, urinary conditions, ulcerated nose, and dropsy. However, no study has evaluated the anticancer effect of P. indica L. In this study, we found that a methanol extract of the leaves and branches of P. indica L. (MEPI) caused cellcycle arrest at the sub-G1 phase and induced apoptosis, as indicated by the activation of caspase-8, -3, -7, and c-PARP. Western blotting revealed that MEPI significantly reduced the levels of markers of the epithelial-mesenchymal transition, such as Vimentin, Snail, Slug, and matrix metallopeptidase 9. Notably, the expression of multidrug resistance-associated protein 1 in triple negative breast cancer (TNBC) was significantly decreased by MEPI. Moreover, the co-treatment with MEPI and doxorubicin resulted in a synergistic reduction in cell viability. MEPI also induced radiation sensitization of TNBC cells. Gas chromatography-mass spectrometry analysis revealed that 5,6-dehydrokawain (DK) is the major constituent of MEPI. Interestingly, DK exerted significant anti-invasive and anti-metastatic effects. Our results provide a strong rationale for investigating the molecular mechanisms of action of MEPI in TNBC.

Nobiletin Enhances Chemosensitivity to Adriamycin through Modulation of the Akt/GSK3β/β⁻Catenin/MYCN/MRP1 Signaling Pathway in A549 Human Non-Small-Cell Lung Cancer Cells

Drug resistance is a major problem in the treatment of non-small-cell lung cancer (NSCLC). In this study, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis was performed to identify the differentially expressed genes in Adriamycin (ADR)-resistant NSCLC A549/ADR cells compared with parental A549 cells. Among the tested phytochemicals, nobiletin (NBT) is able to overcome the ADR resistance of A549/ADR cells. NBT treatment decreased the expression of a neuroblastoma-derived MYC (MYCN) and multidrug resistance-associated protein 1 (MRP1) as well as downregulating Akt, GSK3β, and β-catenin. Consistent with these results, NBT treatment resulted in the accumulation of intracellular ADR. A combination index (CI) assay confirmed the synergistic effect of combined treatment with NBT and ADR in reducing the viability of A549/ADR cells (CI = 0.152). Combined treatment with NBT and ADR enhanced apoptosis in A549/ADR cells, as evidenced by increased caspase-3 activation, poly (ADP-ribose) polymerase (PARP) cleavage, and sub-G1 population compared to treatment with ADR alone. In vivo experiments using a mouse xenograft model revealed that combination therapy with NBT and ADR significantly reduced tumor volume by 84.15%. These data suggest that NBT can sensitize ADR-induced cytotoxicity against A549/ADR cells by inhibiting MRP1 expression, indicating that NBT could serve as an effective adjuvant agent for ADR-based chemotherapy in lung cancer.

Multidisciplinary Investigations on Galphimia glauca: A Mexican Medicinal Plant with Pharmacological Potential

Galphimia glauca (Cav.) Kuntze is an important endemic plant species, which possesses many medicinal properties and has been used in the Mexican traditional medicine for its sedative, anxiolytic, anticonvulsant, antiasthmatic and antiallergic properties. The therapeutic properties of this plant are mainly due to the presence of diverse bioactive compounds such as flavonoids, triterpenoids, and phenolics. Several triterpenoids and flavonoids compounds have been isolated and identified. Modern studies have demonstrated many biological activities such as anti-inflammatory, antidiarrheal, gastroenteritis, antimalarial and cytotoxic activities. Nevertheless, many studies are restricted to the crude extract, and many bioactive compounds are yet to be identified and validated according to its traditional use. However, its commercial exploitation and use are highly limited due to the non-availability of enough plant material and lack of knowledge about its agronomical practices. Moreover, the misinterpretation and mislabeling of closely related species of the genus Galphimia Cav. as G. glauca or G. gracilis is a common problem for its rigorous scientific study and commercial exploitation. The present review provides comprehensive knowledge based on the available scientific literature. To the best of our knowledge, this is the first review on G. glauca. This comprehensive information will certainly provide a guide for the better understanding and utilization of G. glauca for its scientific and industrial exploitation.