Methylglyoxal in combination with 5-Fluorouracil elicits improved chemosensitivity in breast cancer through apoptosis and cell cycle inhibition

Synergistic anti-tumorigenic effect of diosmetin in combination with 5-fluorouracil on human colon cancer xenografts in nude mice

5-Fluorouracil (5-FU) is frequently used to treat colorectal cancer (CRC), but its clinical application is limited by its toxicity. Natural compounds have been combined with chemotherapeutic drugs to reduce chemotherapy-related toxicity. Diosmetin, a natural flavonoid, has demonstrated anticancer effects against CRC. This study investigated diosmetin's potential in combination with 5-FU using a murine model of HCT-116 colon cancer xenografts in nu/nu nude mice. HCT-116 cells were injected into the right flanks of mice, and once tumors reached a size of 50 mm3, the mice were treated with diosmetin (100 mg/kg), 5-FU (30 mg/kg), or a combination of both at two dose levels (100 + 30 mg/kg and 50 + 15 mg/kg) for 4 weeks. Blood and tumors were collected on the final day for further analysis. Mice treated with the higher combination dose exhibited the smallest tumor volume (330.91 ± 88.49 mm3). Biochemistry and histology analysis showed no toxicity or abnormalities in the liver, kidney, and heart with the combination therapy. Immunohistochemistry results revealed a notable reduction in the proliferation marker (Ki67) and inflammation marker (TLR4) in tumors from high-dose combination-treated mice. Moreover, immunofluorescence data indicated increased levels of apoptotic markers (Bax, Caspase-3, p53, p21) and downregulation of anti-apoptotic protein (Bcl-2) in the high-dose combination group. The findings suggest that 100 mg/kg of diosmetin combined with 30 mg/kg 5-FU significantly reduced tumor volume and had a less toxic effect on the heart compared to 5-FU monotherapy.

S-p-bromobenzyl-glutathione cyclopentyl diester (BBGC) as novel therapeutic strategy to enhance trabectedin anti-tumor effect in soft tissue sarcoma preclinical models

Trabectedin, approved for the treatment of soft tissue sarcoma (STS), interferes with cell division and genetic transcription processes. Due to its strong anti-tumor activity in only certain histotypes, several studies on trabectedin combinations are currently ongoing to improve its efficacy. In this study, we aimed to investigate novel potential therapeutic strategies to enhance the anti-tumor effect of trabectedin using integrated in silico, in vitro, and in vivo approaches. For in silico analysis, we screened two public datasets, GSEA M5190 and TCGA SARC. Fibrosarcoma, leiomyosarcoma, dedifferentiated, and myxoid liposarcoma cell lines were used for in vitro studies. For in vivo experiments, fibrosarcoma orthotopic murine model was developed. In silico analysis identified Glo1 as the only druggable target upregulated after trabectedin treatment and correlated with poor prognosis. The specific Glo1 inhibitor, S-p-bromobenzylglutathione cyclopentyl diester (BBGC), increased trabectedin cytotoxicity in STS cells, and restored drug sensitivity in myxoid liposarcoma cells resistant to trabectedin. Moreover, the combined treatment with BBGC and trabectedin had a synergistic antitumor effect in vivo without any additional toxicity to mice. Based on these results, we believe that BBGC warrants further investigation to evaluate its potential clinical use in combination with trabectedin.

Antiproliferative effect of indeno[1,2-d]thiazolo[3,2-a]pyrimidine analogues on IL-6 mediated STAT3 and role of the apoptotic pathway in albino Wistar rats of ethyl carbamate-induced lung carcinoma: In-silico, In-vitro, and In-vivo study

Lung cancer (LC) ranks second most prevalent cancer in females after breast cancer and second in males after prostate cancer. Based on the GLOBOCAN 2020 report, India represented 5.9% of LC cases and 8.1% of deaths caused by the disease. Several clinical studies have shown that LC occurs because of biological and morphological abnormalities and the involvement of altered level of antioxidants, cytokines, and apoptotic markers. In the present study, we explored the antiproliferative activity of indeno[1,2-d]thiazolo[3,2-a]pyrimidine analogues against LC using in-vitro, in-silico, and in-vivo models. In-vitro screening against A549 cells revealed compounds 9B (8-methoxy-5-(3,4,5-trimethoxyphenyl)-5,6-dihydroindeno[1,2-d]thiazolo[3,2-a]pyrimidine) and 12B (5-(4-chlorophenyl)-5,6-dihydroindeno[1,2-d]thiazolo[3,2-a]pyrimidine) as potential pyrimidine analogues against LC. Compounds 9B and 12B were docked with different molecular targets IL-6, Cyt-C, Caspase9, and Caspase3 using AutoDock Vina 4.1 to evaluate the binding affinity. Subsequently, in-vivo studies were conducted in albino Wistar rats through ethyl-carbamate (EC)- induced LC. 9B and 12B imparted significant effects on physiological (weight variation), and biochemical (anti-oxidant [TBAR's, SOD, ProC, and GSH), lipid (TC, TG, LDL, VLDL, and HDL)], and cytokine (IL-2, IL-6, IL-10, and IL-1β) markers in EC-induced LC in albino Wistar rats. Morphological examination (SEM and H&E) and western blotting (IL-6, STAT3, Cyt-C, BAX, Bcl-2, Caspase3, and caspase9) showed that compounds 9B and 12B had antiproliferative effects. Accordingly, from the in-vitro, in-silico, and in-vivo experimental findings, we concluded that 9B and 12B have significant antiproliferative potential and are potential candidates for further evaluation to meet the requirements of investigation of new drug application.

Modulator of TMB-associated immune infiltration (MOTIF) predicts immunotherapy response and guides combination therapy

Patients with high tumor mutational burden (TMB) levels do not consistently respond to immune checkpoint inhibitors (ICIs), possibly because a high TMB level does not necessarily result in adequate infiltration of CD8+ T cells. Using bulk ribonucleic acid sequencing (RNA-seq) data from 9311 tumor samples across 30 cancer types, we developed a novel tool called the modulator of TMB-associated immune infiltration (MOTIF), which comprises genes that can determine the extent of CD8+ T cell infiltration prompted by a certain TMB level. We confirmed that MOTIF can accurately reflect the integrity and defects of the cancer-immunity cycle. By analyzing 84 human single-cell RNA-seq datasets from 32 types of solid tumors, we revealed that MOTIF can provide insights into the diverse roles of various cell types in the modulation of CD8+ T cell infiltration. Using pretreatment RNA-seq data from 13 ICI-treated cohorts, we validated the use of MOTIF in predicting CD8+ T cell infiltration and ICI efficacy. Among the components of MOTIF, we identified EMC3 as a negative regulator of CD8+ T cell infiltration, which was validated via in vivo studies. Additionally, MOTIF provided guidance for the potential combinations of programmed death 1 blockade with certain immunostimulatory drugs to facilitate CD8+ T cell infiltration and improve ICI efficacy.

Repurposing sodium stibogluconate as an uracil DNA glycosylase inhibitor against prostate cancer using a time-resolved oligonucleotide-based drug screening platform

Repurposing drugs can significantly reduce the time and costs associated with drug discovery and development. However, many drug compounds possess intrinsic fluorescence, resulting in aberrations such as auto-fluorescence, scattering and quenching, in fluorescent high-throughput screening assays. To overcome these drawbacks, time-resolved technologies have received increasing attention. In this study, we have developed a rapid and efficient screening platform based on time-resolved emission spectroscopy in order to screen for inhibitors of the DNA repair enzyme, uracil-DNA glycosylase (UDG). From a database of 1456 FDA/EMA-approved drugs, sodium stibogluconate was discovered as a potent UDG inhibitor. This compound showed synergistic cytotoxicity against 5-fluorouracil-resistant cancer cells. This work provides a promising future for time-resolved technologies for high-throughput screening (HTS), allowing for the swift identification of bioactive compounds from previously overlooked scaffolds due to their inherent fluorescence properties.

Phytochemical profiles, antioxidant activities, and synergistic antiproliferative effects of blueberry and apple peel extracts

BACKGROUND

Blueberries and apples exhibit favorable bioactivity and health benefits as a result of their rich phytochemicals. Natural phytochemicals exist in complex forms, but there are few reports on whether have additive, synergistic or antagonistic effects between different phytochemicals. The present study aimed to elucidate the synergistic effects of blueberry extract (BE) and apple peel extract (APE) together with respect to inhibiting the proliferation of HepG2 liver cancer cells. Meanwhile, phytochemical characterization of BE and APE was conducted by HPLC, and total antioxidant activity was determined via a cellular antioxidant activity assay, oxygen radical absorption capacity assay and peroxy radical scavenging capacity assay.

RESULTS

The results showed that BE and APE were rich in phytochemicals and had potent antioxidant activities, which synergistically inhibited cell proliferation. In the bilateral combination, the dose reduction index value increased by two-fold, and the combination index value at 95% inhibition was less than 1. Additionally, BE + APE supplementation could promote the expression levels of p53 and c-myc genes. In conclusion, the BE and APE had strong antioxidant activity and exhibited synergistic inhibition against proliferation of HepG2 cells.

CONCLUSION

The present study can provide a theoretical basis for the synergistic effect of different phytochemicals in health care. © 2023 Society of Chemical Industry.

Lupeol synergizes with 5-fluorouracil to combat c-MET/EphA2 mediated chemoresistance in triple negative breast cancer

Triple-negative breast cancer (TNBC) is the most elusive subtype of breast cancer that encounters treatment dilemmas owing to the paucity of druggable targets. We found hyperactivation of c-MET and ephrin type-A receptor 2 (EphA2) in patients treated with 5FU driven chemotherapy which correlated with lower disease-free survival. However, silencing of both these genes resulted in a marked decrease in the invasive, migratory, and tumorigenic potential of TNBC cells, indicating that a dual target strategy is actionable. Lupeol is a phytochemical, with potent anticancer efficacy and minimal side effects in preclinical studies. A synergistic strategy with 5FU and Lupeol elicited promising anticancer responses in vitro, in vivo, and in patient-derived ex vivo tumor culture models. This synergistic regimen is effective, even in the presence of HGF, which mechanistically orchestrates the activation of c-MET and EphA2. These data lay the foundation for the clinical validation of this combination therapy for TNBC patients.

Glyoxalase 1 inhibitor BBGC suppresses the progression of chronic lymphocytic leukemia and promotes the efficacy of Palbociclib

Chronic lymphocytic leukemia (CLL) is a highly heterogeneous disease. Despite recent tremen-dous progress in managing CLL, the disease remains incurable with clinical therapies, and relapse is inevitable. To overcome this, new diagnostic and prognostic markers need to be investigated. We thus screened through the public database for genes with diagnostic, prognostic, and therapeutic implications in CLL. We further performed RT-qPCR and Western blot analysis to measure the candidate gene and protein expression levels, respectively, in peripheral blood mononuclear cells. Our results indicated that Glyoxalase 1 (GLO1) expression was significantly higher in patients with CLL than in healthy controls. Furthermore, cell proliferation, apoptosis, and cell cycle assay results together indicated that S-p-bromobenzylglutathione cyclopentyl diester (BBGC), an effective inhibitor of GLO1, suppresses the progression of CLL. Bioinformatics analysis revealed that GLO1 expression is closely associated with CDK4 expression in a wide variety of cancer types, and inhibition of CDK4 through silencing of genes or inhibitors can downregulate GLO1 expression. Subsequent validation experiments demonstrated that GLO1 protein levels were downregulated in MEC-1 and Jurkat cell lines after palbociclib exposure, and combination treatment of palbociclib with GLO1 inhibitor BBGC effectively delayed the growth of tumor cell lines.

Quercetin Improves the Anti-angiogenic Property of 5-Fluorouracil on the Human Umbilical Vein Endothelial Cells HUVEC Cell Line

Background: Angiogenesis provides the oxygen and nutrients needed for metastasis and tumor growth, so by inhibiting angiogenesis, metastasis to other parts of the body can be prevented at the first steps of cancer. 5-Fluorouracil (5-FU) as a common chemotherapy drug and Quercetin as a natural compound both have anti-angiogenic properties. Objectives: In the current study improvement of the anti-angiogenic property of 5-FU by combination with quercetin was investigated. Methods: After treating the cells with alone or a combination of drugs the angiogenesis, vascular endothelial growth factor receptors (VEGFRs) gene expression, migration, and viability of the cells were evaluated using chicken chorioallantoic membrane (CAM) assay, real-time RT-PCR, wound healing and MTT assay, respectively. Results: Treatment with alone 5-FU and Que led to a significant reduction in angiogenesis, VEGFR2 and VEGFR1gene expression, migration, and Cell viability. The reductions were significant in the combination state compared to alone treatment. Conclusions: The results showed that the combination treatment with Que with 5-FU enhances the anti-angiogenic property of 5-FU, so it can be proposed as a potential anti-angiogenic and as a result anti-metastatic treatment for future animal studies.

Loss of PRMT7 reprograms glycine metabolism to selectively eradicate leukemia stem cells in CML

Our group has reported previously on the role of various members of the protein arginine methyltransferase (PRMT) family, which are involved in epigenetic regulation, in the progression of leukemia. Here, we explored the role of PRMT7, given its unique function within the PRMT family, in the maintenance of leukemia stem cells (LSCs) in chronic myeloid leukemia (CML). Genetic loss of Prmt7, and the development and testing of a small-molecule specific inhibitor of PRMT7, showed that targeting PRMT7 delayed leukemia development and impaired self-renewal of LSCs in a CML mouse model and in primary CML CD34⁺ cells from humans without affecting normal hematopoiesis. Mechanistically, loss of PRMT7 resulted in reduced expressions of glycine decarboxylase, leading to the reprograming of glycine metabolism to generate methylglyoxal, which is detrimental to LSCs. These findings link histone arginine methylation with glycine metabolism, while suggesting PRMT7 as a potential therapeutic target for the eradication of LSCs in CML.

A Review of Twenty Years of Research on the Regulation of Signaling Pathways by Natural Products in Breast Cancer

Breast cancer (BC) is the second leading cause of death among women, and it has become a global health issue due to the increasing number of cases. Different treatment options, including radiotherapy, surgery, chemotherapy and anti-estrogen therapy, aromatase inhibitors, anti-angiogenesis drugs, and anthracyclines, are available for BC treatment. However, due to its high occurrence and disease progression, effective therapeutic options for metastatic BC are still lacking. Considering this scenario, there is an urgent need for an effective therapeutic strategy to meet the current challenges of BC. Natural products have been screened as anticancer agents as they are cost-effective, possess low toxicity and fewer side effects, and are considered alternative therapeutic options for BC therapy. Natural products showed anticancer activities against BC through the inhibition of angiogenesis, cell migrations, proliferations, and tumor growth; cell cycle arrest by inducing apoptosis and cell death, the downstream regulation of signaling pathways (such as Notch, NF-κB, PI3K/Akt/mTOR, MAPK/ERK, and NFAT-MDM2), and the regulation of EMT processes. Natural products also acted synergistically to overcome the drug resistance issue, thus improving their efficacy as an emerging therapeutic option for BC therapy. This review focused on the emerging roles of novel natural products and derived bioactive compounds as therapeutic agents against BC. The present review also discussed the mechanism of action through signaling pathways and the synergistic approach of natural compounds to improve their efficacy. We discussed the recent in vivo and in vitro studies for exploring the overexpression of oncogenes in the case of BC and the current status of newly discovered natural products in clinical investigations.

Ginsenoside Rh1 inhibits tumor growth in MDA-MB-231 breast cancer cells via mitochondrial ROS and ER stress-mediated signaling pathway

Ginsenoside-Rh1 (Rh1) is a ginseng-derived compound that has been reported to exert anticancer effects by regulating cell cycle arrest and apoptosis according to reactive oxygen species (ROS) production. However, the effects of Rh1 on mitochondrial dysfunction are involved in triple negative breast cancer (TNBC) cell apoptosis, and the related molecular mechanisms remain unknown. Rh1 treatment induced cell toxicity less than 50% at 50 μM. In addition, Rh1 induced apoptosis in TNBC cells through cleaved caspase-3 activation and G1/S arrest. The Rh1-treated TNBC cells showed a significant increase in mitochondrial ROS (mtROS), which in turn increased protein expression of mitochondrial molecules, such as Bak and cytochrome C, and caused the loss of mitochondrial membrane potential. Pretreatment with mitochondria-targeted antioxidant Mito-TEMPO alters the Rh1-reduced rate of mito- and glycol-ATP. Furthermore, Rh1 induces ER stress-mediated calcium accumulation via PERK/eIF2α/ATF4/CHOP pathway. Inhibition of ATF4 by siRNA transfection significantly inhibited Rh1-mediated apoptosis and calcium production. Interestingly, Mito-TEMPO treatment significantly reduced apoptosis and ER stress induced by Rh1. Finally, Rh1 at 5 mg/kg suppressed tumor growth through increased levels of ROS production, cleaved caspase-3, and ATF4 more than 5-fluorouracil treated group. Overall, our results suggest that Rh1 has potential for use in TNBC treatment.

Diosmetin Exerts Synergistic Effects in Combination with 5-Fluorouracil in Colorectal Cancer Cells

5-Fluorouracil (5-FU) is a chemotherapeutic medication commonly used to treat colorectal cancer (CRC); however, the drug-associated adverse effects and toxicity have greatly affected its clinical use. Exploring another therapeutic strategy that lowers the toxicity of 5-FU while having a synergistic effect against CRC is thus a viable option. Diosmetin, a natural flavonoid, has been shown to inhibit the proliferation of many cancer cells, including CRC cells. This study aims to investigate the synergistic effect of diosmetin and 5-FU on HCT116 and HT29 colorectal cancer cells and to explore the apoptotic activity of this combination. The MTT assay was used to assess the viability of cells treated with monotherapy and combination therapy. The combination index (CI) and dose reduction index (DRI) were calculated using the CompuSyn software (version 1.0). The SynergyFinder 2.0 software was used to calculate the synergy score, while the Combenefit software was employed to perform isobologram analysis and synergism determination. The AO/PI double staining technique was used to detect the apoptotic characteristics of cells, whereas the flow cytometry technique was used to investigate the apoptosis induction and cell cycle arrest in cells. The combination of 5-FU and diosmetin showed a synergistic effect in HCT116 cells with a mean CI value of 0.66 ± 0.4, and an additive effect in HT29 cells with a CI value of 1.0 ± 0.2. The DRI of 5-FU in HCT116 cells was three times lower in the combination therapy compared to monotherapy of 5-FU. AO/PI microscopic examination and Annexin V analysis revealed that the combination-treated cells had more apoptotic cells than the monotherapy-treated cells, which was activated mainly through intrinsic apoptosis pathway. HCT116 cell death was confirmed by mitotic arrest in the G2/M phase. Our findings suggest that 5-FU/diosmetin combination exhibits synergistic effect against HCT116 cancer cells, and potentially reduces the unfavorable adverse effect of 5-FU while enhancing the anticancer efficacy by inducing apoptosis and interrupting mitosis. Further research studies are needed to validate the combination’s anti-tumorigenic activities in a xenograft animal model.

The natural isoflavone Biochanin-A synergizes 5-fluorouracil anticancer activity in vitro and in vivo in Ehrlich solid-phase carcinoma model

Isoflavones are considered one of the most extensively studied plant-derived phytoestrogenic compounds. Of these, Biochanin A (Bio-A), a natural isoflavone abundant in cabbage, alfalfa, and red clover, has drawn a lot of attention. As reported in multiple studies, Bio-A possesses a promising anticancer activity against estrogen receptor-positive (ER+)  breast cancer. The current study investigated the working hypothesis that Bio-A could synergistically enhance the potency of 5-fluorouracil (5-FU) in ER+ breast cancer. The hypothesis was tested both in vitro on hormone receptor-positive (MCF-7) and triple-negative breast cancer cells (MDA-MB231). Additionally, in vivo studies were performed in the Ehrlich solid-phase carcinoma mouse model. The in vitro cytotoxicity studies revealed that Bio-A synergistically increased the potency of 5-FU in both MCF-7 and MDA-MB231 cell lines. The synergistic effect of 5-FU/Bio-A combination was verified in vivo. The combination therapy (where 5-FU was used at one fourth its full dose) led to a significant 75% reduction in tumor volume after two treatment cycles. This was in addition to producing a significant 2.1-fold increase in tumor necrosis area% compared to mock-treated control. In conclusion, the current study presents the first preclinical evidence for the potential merit of 5-FU/Bio-A combination for the treatment of ER+ breast cancer. The synergistic antitumor effect of Bio-A/ 5-FU combination can be, at least partly, attributed to Bio-A-mediated suppression of ER-α/Akt axis and the augmentation of 5-FU-mediated proapoptotic effects. © 2022 John Wiley & Sons, Ltd.

Active mitochondrial respiration in cancer: a target for the drug

The relative contribution of mitochondrial respiration and subsequent energy production in malignant cells has remained controversial to date. Enhanced aerobic glycolysis and impaired mitochondrial respiration have gained more attention in the metabolic study of cancer. In contrast to the popular concept, mitochondria of cancer cells oxidize a diverse array of metabolic fuels to generate a majority of the cellular energy by respiration. Several mitochondrial respiratory chain (MRC) subunits' expressions are critical for the growth, metastasis, and cancer cell invasion. Also, the assembly factors, which regulate the integration of individual MRC complexes into native super-complexes, are upregulated in cancer. Moreover, a series of anti-cancer drugs function by inhibiting respiration and ATP production. In this review, we have specified the roles of mitochondrial fuels, MRC subunits, and super-complex assembly factors that promote active respiration across different cancer types and discussed the potential roles of MRC inhibitor drugs in controlling cancer.

Baicalin; a promising chemopreventive agent, enhances the antitumor effect of 5-FU against breast cancer and inhibits tumor growth and angiogenesis in Ehrlich solid tumor

Despite considerable advances in cancer treatment, chemotherapy remains a cornerstone in breast cancer therapy. Therefore, reducing chemoresistance and adverse effects of chemotherapy is a priority. In this regard, Baicalin (BA) is the dominant natural flavonoid extracted from the roots of Scutellaria baicalensis showed fascinating antitumor activity in many types of cancers, including breast cancer. The present study aimed to explore the chemopreventive and antitumor action of baicalin alone and in combination with 5-FU in addition to its ability to enhance the antitumor effect of 5-FU on breast cancer using the Ehrlich solid tumor-mice model.

MATERIALS AND METHODS

A total of 70 female mice were divided into seven groups (1st group, saline group; 2nd group, DMSO group; 3rd group, BA+EST group; 4th group, EST group; 5th group, EST+5-FU; 6th group, EST+BA group; 7th group, EST+5-FU+BA).tumors were assessed by weight and histopathological examination. Inflammation, angiogenesis, and apoptosis were examined by ELISA, qRT-PCR, and immunohistochemical examinations.

RESULTS

showed that pre-treatment with baicalin and treatment with baicalin and/or 5-FU significantly reduced inflammation and angiogenesis indicated by suppression of NF-kB/ IL-1β and VEGF amplification loop with marked elevation in apoptosis indicated by up-regulation of apoptotic caspase-3, pro-apoptotic p53, Bax and downregulation of anti-apoptotic Bcl-2.

CONCLUSION

BA is a promising preventive or adjuvant therapy in breast cancer treatment with 5-FU mainly via cooperative inhibition of inflammation, angiogenesis, and triggering apoptotic cell death.

The "dextran-magnetic layered double hydroxide-fluorouracil" drug delivery system exerts its anti-tumor effect by inducing lysosomal membrane permeability in the process of cell death

The "dextran-magnetic layered double hydroxide-fluorouracil" (DMF) drug delivery system is a new type of pharmaceutic preparation that can cause cancer cell oncosis. In the present study, we used different experimental methods such as MTT, cycle assay, reactive oxygen species (ROS) assay, Annexin V-FITC/PI, Giemsa stainings, transmission electron microscopy, immunofluorescence staining and Western blotting to study the mechanism of expansion death by using Hydroxychloroquine (HCQ) as a positive control and 5-Fluorouracil (5-Fu) as reference. The results showed that DMF exhibited a better anti-tumor effect than 5-Fu in the process of cell death, and the pharmacological mechanism of 5-Fu was changed by its preparation DMF. The mechanism of cancer cell death induced by DMF was similar to that of HCQ. But DMF intervention did not cause a large amount of accumulation of mitochondrial reactive oxygen species, and the location of lysosomotropic LysoTracker Red (LTR) staining induced by DMF was closer to the nucleus or nuclear membrane. Lysosomal membrane permeability (LMP) and its subsequent the explosive death of cancer cells may be mainly related to the direct action of DMF with different organelles.