Comparison of methods for evaluating drug-drug interaction

Pancreatic cancer organoid-screening captures personalized sensitivity and chemoresistance suppression upon cytochrome P450 3A5-targeted inhibition

Cytochrome P450 3A5 (CYP3A5) has been proposed as a predictor of therapy response in subtypes of pancreatic ductal adenocarcinoma cancer (PDAC). To validate CYP3A5 as a therapeutic target, we developed a high-content image organoid-based screen to quantify the phenotypic responses to the selective inhibition of CYP3A5 enzymatic activity by clobetasol propionate (CBZ), using a cohort of PDAC-derived organoids (PDACOs). The chemoresistance of PDACOs to a panel of standard-of-care drugs, alone or in combination with CBZ, was investigated. PDACO pharmaco-profiling revealed CBZ to have anti-cancer activity that was dependent on the CYP3A5 level. In addition, CBZ restored chemo-vulnerability to cisplatin in a subset of PDACOs. A correlative proteomic analysis established that CBZ caused the suppression of multiple cancer pathways sustained by or associated with a mutant form of p53. Limiting the active pool of CYP3A5 enables targeted and personalized therapy to suppress pro-oncogenic mechanisms that fuel chemoresistance in some PDAC tumors.

Pentagalloyl Glucose (PGG) Exhibits Anti-Cancer Activity against Aggressive Prostate Cancer by Modulating the ROR1 Mediated AKT-GSK3β Pathway

Androgen-receptor-negative, androgen-independent (ARneg-AI) prostate cancer aggressively proliferates and metastasizes, which makes treatment difficult. Hence, it is necessary to continue exploring cancer-associated markers, such as oncofetal Receptor Tyrosine Kinase like Orphan Receptor 1 (ROR1), which may serve as a form of targeted prostate cancer therapy. In this study, we identify that Penta-O-galloyl-β-D-glucose (PGG), a plant-derived gallotannin small molecule inhibitor, modulates ROR1-mediated oncogenic signaling and mitigates prostate cancer phenotypes. Results indicate that ROR1 protein levels were elevated in the highly aggressive ARneg-AI PC3 cancer cell line. PGG was selectively cytotoxic to PC3 cells and induced apoptosis of PC3 (IC50 of 31.64 µM) in comparison to normal prostate epithelial RWPE-1 cells (IC50 of 74.55 µM). PGG was found to suppress ROR1 and downstream oncogenic pathways in PC3 cells. These molecular phenomena were corroborated by reduced migration, invasion, and cell cycle progression of PC3 cells. PGG minimally and moderately affected RWPE-1 and ARneg-AI DU145, respectively, which may be due to these cells having lower levels of ROR1 expression in comparison to PC3 cells. Additionally, PGG acted synergistically with the standard chemotherapeutic agent docetaxel to lower the IC50 of both compounds about five-fold (combination index = 0.402) in PC3 cells. These results suggest that ROR1 is a key oncogenic driver and a promising target in aggressive prostate cancers that lack a targetable androgen receptor. Furthermore, PGG may be a selective and potent anti-cancer agent capable of treating ROR1-expressing prostate cancers.

Effects of okadaic acid, azaspiracid-1, yessotoxin and their binary mixtures on human intestinal Caco-2 cells

Phycotoxins are responsible for foodborne intoxications. Symptoms depend on the ingested toxins but mostly imply gastro-intestinal and neurological disorders. Importantly, humans are exposed to combinations of several phycotoxins, resulting in possible mixture effects. Most previous studies, however, have been focused on single toxin effects. Thus, the aim of this study was to examine the effects of binary mixtures of three main phycotoxins, okadaic acid (OA), azaspiracid-1 (AZA1) and yessotoxin (YTX), on human intestinal Caco-2 cells. The focus was placed on cell viability studies and inflammation responses using a multi-parametric approach to assess cell population (nuclei staining), cell metabolism/viability (reductase activity and lysosomal integrity), and release of inflammation markers (e.g., interleukins). Mixture effects were evaluated using the concentration addition (CA) and independent action (IA) models. Our assays show that none of the toxins had an impact on the cell population in the tested concentration range. Only OA modulated reductase activity, while all three toxins had strong effects on lysosomal integrity. Furthermore, all toxins triggered the release of interleukin 8 (IL-8), with OA being most potent. Mixture effect analysis showed additivity in most cases. However, supra-additivity was observed in regards to IL-6 and IL-8 release for combinations implying high concentrations of OA. This study extends the knowledge on mixture effects of phycotoxins in human cells.

Receptor tyrosine kinase-like orphan receptor 1 inhibitor strictinin exhibits anti-cancer properties against highly aggressive androgen-independent prostate cancer

Aim

It is important to identify anti-cancer compounds that can inhibit specific molecular targets to eradicate androgen-receptor negative (ARneg), androgen-independent (AI) prostate cancer, which is an aggressive form of prostate cancer with limited treatment options. The goal of this study was to selectively target prostate cancer cells that have high levels of oncogenic protein Receptor tyrosine kinase-like orphan receptor 1 (ROR1) by using strictinin, a small molecule ROR1 inhibitor.

Methods

The methods performed in this study include western blots, methyl thiazolyl tetrazolium (MTT) proliferation assays, phosphatidylserine apoptosis assays, apoptosis flow cytometry (Annexin V, caspase 3/7), migration scratch assays, Boyden chamber invasion assays, and cell cycle flow cytometry.

Results

Strictinin was most lethal against PC3 [half-maximal drug inhibitory concentration (IC50) of 277.2 µmol/L], an ARneg-AI cell type that expresses the highest levels of ROR1. Strictinin inhibited ROR1 expression, downstream phosphatidylinositol 3-kinase (PI3K)-protein kinase B (AKT)-glycogen synthase kinase 3beta (GSK3β) pro-survival signaling, and epithelial-to-mesenchymal transition markers in PC3 cells. Additionally, strictinin decreased PC3 cell migration and invasion, while increasing S-phase cell cycle arrest. In ARneg-AI DU145 cells, strictinin inhibited ROR1 expression and modulated downstream AKT-GSK3β signaling. Furthermore, strictinin exhibited anti-migratory, anti-invasive, but minimal pro-apoptotic effects in DU145 cells likely due to DU145 having less ROR1 expression in comparison to PC3 cells. Throughout the study, strictinin minimally impacted the phenotype of normal prostatic epithelial cells RWPE-1 (IC50 of 658.5 µmol/L). Strictinin was further identified as synergistic with docetaxel [combination index (CI) = 0.311] and the combination therapy was found to reduce the IC50 of strictinin to 38.71 µmol/L in PC3 cells.

Conclusions

ROR1 is an emerging molecular target that can be utilized for treating prostate cancer. The data from this study establishes strictinin as a potential therapeutic agent that targets ARneg-AI prostate cancer with elevated ROR1 expression to reduce the migration, invasion, cell cycle progression, and survival of prostate cancer.

Delineating the interplay between oncogenic pathways and immunity in anaplastic Wilms tumors

Wilms tumors are highly curable in up to 90% of cases with a combination of surgery and radio-chemotherapy, but treatment-resistant types such as diffuse anaplastic Wilms tumors pose significant therapeutic challenges. Our multi-omics profiling unveils a distinct desert-like diffuse anaplastic Wilms tumor subtype marked by immune/stromal cell depletion, TP53 alterations, and cGAS-STING pathway downregulation, accounting for one-third of all diffuse anaplastic cases. This subtype, also characterized by reduced CD8 and CD3 infiltration and active oncogenic pathways involving histone deacetylase and DNA repair, correlates with poor clinical outcomes. These oncogenic pathways are found to be conserved in anaplastic Wilms tumor cell models. We identify histone deacetylase and/or WEE1 inhibitors as potential therapeutic vulnerabilities in these tumors, which might also restore tumor immunogenicity and potentially enhance the effects of immunotherapy. These insights offer a foundation for predicting outcomes and personalizing treatment strategies for aggressive pediatric Wilms tumors, tailored to individual immunological landscapes.

Therapeutic Advantage of Targeting PRMT5 in Combination with Chemotherapies or EGFR/HER2 Inhibitors in Triple-Negative Breast Cancers

Purpose

Triple-negative breast cancer (TNBC) is the most aggressive breast cancer subgroup characterized by a high risk of resistance to chemotherapies and high relapse potential. TNBC shows inter-and intra-tumoral heterogeneity; more than half expresses high EGFR levels and about 30% are classified as HER2-low breast cancers. High PRMT5 mRNA levels are associated with poor prognosis in TNBC and inhibiting PRMT5 impairs the viability of subsets of TNBC cell lines and delays tumor growth in TNBC mice models. TNBC patients may therefore benefit from a treatment targeting PRMT5. The aim of this study was to assess the therapeutic benefit of combining a PRMT5 inhibitor with different chemotherapies used in the clinics to treat TNBC patients, or with FDA-approved inhibitors targeting the HER family members.

Methods

The drug combinations were performed using proliferation and colony formation assays on TNBC cell lines that were sensitive or resistant to EPZ015938, a PRMT5 inhibitor that has been evaluated in clinical trials. The chemotherapies analyzed were cisplatin, doxorubicin, camptothecin, and paclitaxel. The targeted therapies tested were erlotinib (EGFR inhibitor), neratinib (EGFR/HER2/HER4 inhibitor) and tucatinib (HER2 inhibitor).

Results

We found that PRMT5 inhibition synergized mostly with cisplatin, and to a lesser extent with doxorubicin or camptothecin, but not with paclitaxel, to impair TNBC cell proliferation. PRMT5 inhibition also synergized with erlotinib and neratinib in TNBC cell lines, especially in those overexpressing EGFR. Additionally, a synergistic interaction was observed with neratinib and tucatinib in a HER2-low TNBC cell line as well as in a HER2-positive breast cancer cell line. We noticed that synergy can be obtained in TNBC cell lines that were resistant to PRMT5 inhibition alone.

Conclusion

Altogether, our data highlight the therapeutic potential of targeting PRMT5 using combinatorial strategies for the treatment of subsets of TNBC patients.

The neuroprotective effects of the combined extract of mulberry fruit and mulberry leaf against hydrogen peroxide-induced cytotoxicity in SH-SY5Y Cells

The prevalence of dementia is increasing, and most of the causes are related to neuronal cell death. Unfortunately, no effective strategy is available for protecting against this condition. Based on the use of the synergistic concept together with the positive modulation effect of both mulberry fruit and mulberry leaf on dementia, we hypothesized that the combined extract of mulberry fruit and mulberry leaf (MFML) should mitigate neuronal cell death. Neuronal cell damage was induced in SH-SY5Y cells by exposure to hydrogen peroxide at a dose of 200 μM. SH-SY5Y cells were given MFML at doses of 62.5 and 125 μg/mL before induced cytotoxicity. Then, the cell viability was determined via MTT assay, and the possible underlying mechanisms were investigated via the alterations of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), malondialdehyde (MDA), nuclear factor-κB (NF-κB), and tumor necrosis factor-alpha (TNF-α), together with apoptotic factors including (B-cell lymphoma 2) BCL2, Casapase-3 and Caspase-9. The results showed that MFML significantly enhanced cell viability. It also significantly decreased MDA level, NF-κB, TNF-α, Casapase-3, Caspase-9, but increased SOD, GSH-Px and BCL2. These data demonstrated the neuroprotective effect of MFML. The possible underlying mechanisms might occur partly via the improvement of the inappropriate apoptotic mechanisms via BCL2, Casapase-3 and Caspase-9 together with the decrease in neurodegeneration induced by the reduction of inflammation and oxidative stress. In conclusion, MFML is a potential neuroprotectant candidate against neuronal cell injury. However, toxicity, animal studies, and clinical trials are essential to confirm these benefits.

A novel designed membrane-active peptide for the control of foodborne Salmonella enterica serovar Typhimurium

The main cause of non-typhoidal Salmonella (NTS) infection in humans is ingestion of contaminated animal-derived foods such as eggs, poultry and dairy products. These infections highlight the need to develop new preservatives to increase food safety. Antimicrobial peptides (AMPs) have the potential to be further developed as food preservative agents and join nisin, the only AMP currently approved, for use as a preservative in food. Acidocin J1132β, a bacteriocin produced by probiotic Lactobacillus acidophilus, displays no toxicity to humans, however it exhibits only low and narrow-spectrum antimicrobial activity. Accordingly, four peptide derivatives (A5, A6, A9, and A11) were modified from acidocin J1132β by truncation and amino acid substitution. Among them, A11 showed the most antimicrobial activity, especially against S. Typhimurium, as well as a favorable safety profile. It tended to form an α-helix structure upon encountering negatively charged-mimicking environments. A11 caused transient membrane permeabilization and killed bacterial cells through membrane depolarization and/or intracellular interactions with bacterial DNA. A11 maintained most of its inhibitory effects when heated, even when exposed to temperatures up to 100 °C. Notably, it inhibited drug-resistant S. Typhimurium and its monophasic variant strains. Furthermore, the combination of A11 and nisin was synergistic against drug-resistant strains in vitro. Taken together, this study indicated that a novel antimicrobial peptide derivative (A11), modified from acidocin J1132β, has the potential to be a bio-preservative to control S. Typhimurium contamination in the food industry.

Combination of marine bioactive compounds and extracts for the prevention and treatment of chronic diseases

Background

In recent years, marine-based functional foods and combination therapy are receiving greater recognition for their roles in healthy lifestyle applications and are being investigated as viable and effective strategies for disease treatment or prevention.

Aim of the review

This review article presents and discusses the relevant scientific publications that have studied the synergistic and additive effects of natural marine bioactive compounds and extract combinations with anti-obesity, anti-inflammatory, antioxidant, and chemopreventive activities in the last two decades. The paper presents the mechanism of action and health benefits of developed combinations and discusses the limitation of the studies. Furthermore, it recommends alternatives and directions for future studies. Finally, it highlights the factors for developing novel combinations of marine bioactive compounds.

Key scientific concepts of review

Combination of marine bioactive compounds or extracts affords synergistic or additive effects by multiple means, such as multi-target effects, enhancing the bioavailability, boosting the bioactivity, and neutralizing adverse effects of compounds in the mixture. For the development of marine-based combinations, there are key points for consideration and issues to address: knowledge of the mechanism of action of individual compounds and their combinations, optimum ratio and dosing of compounds, and experimental models must all be taken into account. Strategies to increase the number and diversity of marine combinations, and further development of marine-based functional foods, are available. However, only a small number of natural marine bioactive combinations have been assessed, and most research has been focused on fish oil and carotenoid synergy. Therefore, more research and resources should be spent on developing novel marine bioactive combinations as functional foods and nutraceuticals.

Commensal bacteria of the lung microbiota synergistically inhibit inflammation in a three-dimensional epithelial cell model

Patients with chronic lung disease suffer from persistent inflammation and are typically colonized by pro-inflammatory pathogenic bacteria. Besides these pathogens, a wide variety of commensal species is present in the lower airways but their role in inflammation is unclear. Here, we show that the lung microbiota contains several species able to inhibit activation of the pro-inflammatory NF-κB pathway and production of interleukin 8 (IL-8), triggered by lipopolysaccharide (LPS) or H₂O₂, in a physiologically relevant three-dimensional (3D) lung epithelial cell model. We demonstrate that the minimal dose needed for anti-inflammatory activity differs between species (with the lowest dose needed for Rothia mucilaginosa), and depends on the type of pro-inflammatory stimulus and read out. Furthermore, we evaluated synergistic activity between pairs of anti-inflammatory bacteria on the inhibition of the NF-κB pathway and IL-8 secretion. Synergistic anti-inflammatory activity was observed for 4/10 tested consortia. These findings indicate that various microbiota members can influence lung inflammation either alone or as a consortium. This information can contribute to a better understanding of the lung microbiota in chronic lung disease development and process, and could open up new avenues for treatment.

Fixed Dose Versus Loose Dose: Analgesic Combinations

Combinations of drugs may be fixed (two or more entities in a single product) or loose (two or more agents taken together but as individual agents) to help address multimechanistic pain. The use of opioids plus nonopioids can result in lower opioid consumption without sacrificing analgesic benefits. Drug combinations may offer additive or synergistic benefits. A variety of fixed-dose combination products are available on the market such as diclofenac plus thiocolchicoside, acetaminophen and caffeine, acetaminophen and opioid, ibuprofen and acetaminophen, tramadol and acetaminophen, and others. Fixed-dose combination products offer predictable pharmacokinetics and pharmacodynamics, known adverse events, and can reduce the pill burden. However, they are limited to certain drug combinations and doses; loose dosing allows prescribers the versatility to meet individual patient requirements as well as the ability to titrate as needed. Not all drug combinations offer synergistic benefits, which depend on the drugs and their doses. Certain drugs offer dual mechanisms of action in a single molecule, such as tapentadol, and these may further be used in combination with other analgesics. New technology allows for co-crystal productions of analgesic agents which may further improve drug characteristics, such as bioavailability. Combination analgesics are important additions to the analgesic armamentarium and may offer important benefits at lower doses than monotherapy.

3,4-Dicaffeoylquinic Acid from the Medicinal Plant Ilex kaushue Disrupts the Interaction Between the Five-Fold Axis of Enterovirus A-71 and the Heparan Sulfate Receptor

While infections by enterovirus A71 (EV-A71) are generally self-limiting, they can occasionally lead to serious neurological complications and death. No licensed therapies against EV-A71 currently exist. Using anti-virus-induced cytopathic effect assays, 3,4-dicaffeoylquinic acid (3,4-DCQA) from Ilex kaushue extracts was found to exert significant anti-EV-A71 activity, with a broad inhibitory spectrum against different EV-A71 genotypes. Time-of-drug-addition assays revealed that 3,4-DCQA affects the initial phase (entry step) of EV-A71 infection by directly targeting viral particles and disrupting viral attachment to host cells. Using resistant virus selection experiments, we found that 3,4-DCQA targets the glutamic acid residue at position 98 (E98) and the proline residue at position 246 (P246) in the 5-fold axis located within the VP1 structural protein. Recombinant viruses harboring the two mutations were resistant to 3,4-DCQA-elicited inhibition of virus attachment and penetration into human rhabdomyosarcoma (RD) cells. Finally, we showed that 3,4-DCQA specifically inhibited the attachment of EV-A71 to the host receptor heparan sulfate (HS), but not to the scavenger receptor class B member 2 (SCARB2) and P-selectin glycoprotein ligand-1 (PSGL1). Molecular docking analysis confirmed that 3,4-DCQA targets the 5-fold axis to form a stable structure with the E98 and P246 residues through noncovalent and van der Waals interactions. The targeting of E98 and P246 by 3,4-DCQA was found to be specific; accordingly, HS binding of viruses carrying the K242A or K244A mutations in the 5-fold axis was successfully inhibited by 3,4-DCQA.The clinical utility of 3,4-DCQA in the prevention or treatment of EV-A71 infections warrants further scrutiny. IMPORTANCE The canyon region and the 5-fold axis of the EV-A71 viral particle located within the VP1 protein mediate the interaction of the virus with host surface receptors. The three most extensively investigated cellular receptors for EV-A71 include SCARB2, PSGL1, and cell surface heparan sulfate. In the current study, a RD cell-based anti-cytopathic effect assay was used to investigate the potential broad spectrum inhibitory activity of 3,4-DCQA against different EV-A71 strains. Mechanistically, we demonstrate that 3,4-DCQA disrupts the interaction between the 5-fold axis of EV-A71 and its heparan sulfate receptor; however, no effect was seen on the SCARB2 or PSGL1 receptors. Taken together, our findings show that this natural product may pave the way to novel anti-EV-A71 therapeutic strategies.

Integrated in silico - in vitro strategy for the discovery of potential xanthine oxidase inhibitors from Egyptian propolis and their synergistic effect with allopurinol and febuxostat

Xanthine oxidase (XO) has been well-recognized as a validated target for the treatment of hyperuricemia and gout. Currently, there are two drugs in clinical use that shut down XO overactivity, allopurinol and febuxostat; however, detrimental side effects restrict their applications. Propolis is a unique natural adhesive biomass of structurally variable and biologically active metabolites that exert remarkable health benefits. Moreover, combination drug therapy has become a promising pharmacotherapeutic strategy directed for reformulating existing drugs into new combination entities with potentiating therapeutic impacts. In this study, computer-aided molecular docking and MD simulations accompanied by biochemical testing were used for mining novel pharmacologically active chemical entities from Egyptian propolis to combat hyperuricemia. Further, with a view to decrease the potential toxicity of synthetic drugs and enhance efficacy, propolis hits were subjected to combination analysis with each of allopurinol and febuxostat. More specifically, Glide docking was utilized for a structure-based virtual screening of in-house datasets comprising various Egyptian propolis metabolites. Rosmarinic acid, luteolin, techtochrysin and isoferulic acid were the most promising virtual hits. In vitro XO inhibitory assays demonstrated the ability of these hits to significantly inhibit XO in a dose-dependent manner. Molecular docking and MD simulations revealed a cooperative binding mode between the discovered hits and standard XO inhibitors within the active site. Subsequently, the most promising hits were tested in a fixed-ratio combination setting with allopurinol and febuxostat separately to assess their combined effects on XO catalytic inhibition. The binary combination of each techtochrysin and rosmarinic acid with febuxostat displayed maximal synergy at lower effect levels. In contrast, individually, techtochrysin and rosmarinic acid with allopurinol cooperated synergistically at high dose levels. Taken together, the suggested strategy seems imperative to ensure a steady supply of new therapeutic options sourced from Egyptian propolis to regress the development of hyperuricemia.

Morphological Characterization of Antibiotic Combinations

Combination therapies are common in many therapeutic contexts, including infectious diseases and cancer. A common approach for evaluating combinations in vitro is to assess effects on cell growth as synergistic, antagonistic, or neutral using "checkerboard" experiments to systematically sample combinations of agents in multiple doses. To further understand the effects of antibiotic combinations, we employed high-content imaging to study the morphological changes caused by combination treatments in checkerboard experiments. Using an automated, unsupervised image analysis approach to group morphologies, and an "expert-in-the-loop" to annotate them, we attributed the heterogeneous morphological changes ofEscherichia coli cells to varying doses of both single-agent and combination treatments. We identified patterns of morphological change, including morphological potentiation, competition, and the emergence of unexpected morphologies. We found these frequently did not correlate with synergistic or antagonistic effects on viability, suggesting morphological approaches may provide a distinctive signature of the biological interaction between compounds over a range of conditions. Among the unexpected morphologies we observed, there were transitional changes associated with intermediate doses of compounds and uncharacterized phenotypes associated with well-studied antibiotics. Our approach exemplifies how unsupervised image analysis and expert knowledge can be combined to reckon with complex phenotypic changes arising from combination screening, dose titrations, or polypharmacology. In this way, quantification of morphological diversity across treatment conditions could aid in analysis and prioritization of complementary pairings of antibiotic agents by more closely capturing the true signature of the integrated cellular response.

Persister control by leveraging dormancy associated reduction of antibiotic efflux

Persistent bacterial infections do not respond to current antibiotic treatments and thus present a great medical challenge. These conditions have been linked to the formation of dormant subpopulations of bacteria, known as persister cells, that are growth-arrested and highly tolerant to conventional antibiotics. Here, we report a new strategy of persister control and demonstrate that minocycline, an amphiphilic antibiotic that does not require active transport to penetrate bacterial membranes, is effective in killing Escherichia coli persister cells [by 70.8 ± 5.9% (0.53 log) at 100 μg/mL], while being ineffective in killing normal cells. Further mechanistic studies revealed that persister cells have reduced drug efflux and accumulate more minocycline than normal cells, leading to effective killing of this dormant subpopulation upon wake-up. Consistently, eravacycline, which also targets the ribosome but has a stronger binding affinity than minocycline, kills persister cells by 3 logs when treated at 100 μg/mL. In summary, the findings of this study reveal that while dormancy is a well-known cause of antibiotic tolerance, it also provides an Achilles’ heel for controlling persister cells by leveraging dormancy associated reduction of drug efflux.

Bacterial persister cells are dormant phenotypic variants that are highly tolerant to most antibiotics; and thus, present a major challenge to infection control. This motivated us to develop new strategies that can specifically target the persister population. It is known that persister formation is associated with reduced membrane potential and cellular activities. Thus, we hypothesize that persister cells have reduced drug efflux compared to normal cells and accumulate more antimicrobial agents that can penetrate the membranes of persister cells. By testing this hypothesis, we developed a new set of criteria for selecting persister control agents and demonstrated effective control of Escherichia coli persister cells by minocycline, rifamycin SV, and eravacycline. Our results revealed that these agents are more effective against persister cells than normal cells and the killing occurred during persister wake-up. Collectively, these results demonstrate a new strategy for persister control by leveraging dormancy associated changes in bacterial physiology. The findings may contribute to future drug discovery and the treatment of persistent infections.

The PKN1- TRAF1 signaling axis as a potential new target for chronic lymphocytic leukemia

TRAF1 is a pro-survival adaptor molecule in TNFR superfamily (TNFRSF) signaling. TRAF1 is overexpressed in many B cell cancers including refractory chronic lymphocytic leukemia (CLL). Little has been done to assess the role of TRAF1 in human cancer. Here we show that the protein kinase C related kinase Protein Kinase N1 (PKN1) is required to protect TRAF1 from cIAP-mediated degradation during constitutive CD40 signaling in lymphoma. We show that the active phospho-Thr774 form of PKN1 is constitutively expressed in CLL but minimally detected in unstimulated healthy donor B cells. Through a screen of 700 kinase inhibitors, we identified two inhibitors, OTSSP167, and XL-228, that inhibited PKN1 in the nanomolar range and induced dose-dependent loss of TRAF1 in RAJI cells. OTSSP167 or XL-228 treatment of primary patient CLL samples led to a reduction in TRAF1, pNF-κB p65, pS6, pERK, Mcl-1 and Bcl-2 proteins, and induction of activated caspase-3. OTSSP167 synergized with venetoclax in inducing CLL death, correlating with loss of TRAF1, Mcl-1, and Bcl-2. Although correlative, these findings suggest the PKN1-TRAF1 signaling axis as a potential new target for CLL. These findings also suggest the use of the orally available inhibitor OTSSP167 in combination treatment with venetoclax for TRAF1 overexpressing CLL.

Pan-RAF inhibitor LY3009120 is highly synergistic with low-dose cytarabine, but not azacitidine, in acute myeloid leukemia with RAS mutations

Alterations in RAS oncogenes have been implicated in various types of cancer, including acute myeloid leukemia (AML). Considering that currently, there are no targeted therapies for patients with RAS-mutated AML despite the poor outcomes, RAF may be a potential target for AML. In this study, we first analyzed the efficacy of different MAPK inhibitors in AML cell lines. We found that LY3009120, a pan-RAF inhibitor, significantly decreased cell survival in RAS-mutated AML cell lines. We then investigated the synergistic effects of LY3009120 with either cytarabine or azacitidine. We found that the combination of low-dose cytarabine and LY3009120 showed a synergistic effect in NRAS-mutated HL-60 cells and KRAS-mutated NB4 cells. This effect was caused by a decrease in proliferation, induction of apoptosis, and cell growth arrest through a decrease in phosphorylated MEK and ERK along with a cytotoxic response occurring specifically for the RAS mutation of the pan-RAF inhibitor LY3009120. In addition, we confirmed that combination treatment with low-dose cytarabine and LY3009120 led to an increase in apoptosis in primary AML cells. Our findings indicate that combination therapy with pan-RAF inhibitor LY3009120 and low-dose cytarabine may be a promising treatment strategy for RAS-mutated AML.

Water-soluble tocopherol derivatives inhibit SARS-CoV-2 RNA-dependent RNA polymerase

The recent emergence of a novel coronavirus, SARS-CoV-2, has led to the global pandemic of the severe disease COVID-19 in humans. While efforts to quickly identify effective antiviral therapies have focused largely on repurposing existing drugs ^1-4 , the current standard of care, remdesivir, remains the only authorized antiviral intervention of COVID-19 and provides only modest clinical benefits ⁵ . Here we show that water-soluble derivatives of α-tocopherol have potent antiviral activity and synergize with remdesivir as inhibitors of the SARS-CoV-2 RNA-dependent RNA polymerase (RdRp). Through an artificial-intelligence-driven in silico screen and in vitro viral inhibition assay, we identified D-α-tocopherol polyethylene glycol succinate (TPGS) as an effective antiviral against SARS-CoV-2 and β-coronaviruses more broadly that also displays strong synergy with remdesivir. We subsequently determined that TPGS and other water-soluble derivatives of α-tocopherol inhibit the transcriptional activity of purified SARS-CoV-2 RdRp and identified affinity binding sites for these compounds within a conserved, hydrophobic interface between SARS-CoV-2 nonstructural protein 7 and nonstructural protein 8 that is functionally implicated in the assembly of the SARS-CoV-2 RdRp ⁶ . In summary, we conclude that solubilizing modifications to α-tocopherol allow it to interact with the SARS-CoV-2 RdRp, making it an effective antiviral molecule alone and even more so in combination with remdesivir. These findings are significant given that many tocopherol derivatives, including TPGS, are considered safe for humans, orally bioavailable, and dramatically enhance the activity of the only approved antiviral for SARS-CoV-2 infection ^7-9 .

G-quadruplexes mark alternative lengthening of telomeres

About 10-15% of all human cancer cells employ a telomerase-independent recombination-based telomere maintenance method, known as alternative lengthening of telomere (ALT), of which the full mechanism remains incompletely understood. While implicated in previous studies as the initiating signals for ALT telomere repair, the prevalence of non-canonical nucleic acid structures in ALT cancers remains unclear. Extending earlier reports, we observe higher levels of DNA/RNA hybrids (R-loops) in ALT-positive (ALT+) compared to telomerase-positive (TERT+) cells. Strikingly, we observe even more pronounced differences for an associated four-stranded nucleic acid structure, G-quadruplex (G4). G4 signals are found at the telomere and are broadly associated with telomere length and accompanied by DNA damage markers. We establish an interdependent relationship between ALT-associated G4s and R-loops and confirm that these two structures can be spatially linked into unique structures, G-loops, at the telomere. Additionally, stabilization of G4s and R-loops cooperatively enhances ALT-activity. However, co-stabilization at higher doses resulted in cytotoxicity in a synergistic manner. Nuclear G4 signals are significantly and reproducibly different between ALT+ and TERT+ low-grade glioma tumours. Together, we present G4 as a novel hallmark of ALT cancers with potential future applications as a convenient biomarker for identifying ALT+ tumours and as therapeutic targets.

A Quantitative Pharmacology Model of Exosome-Mediated Drug Efflux and Perturbation-Induced Synergy

Exosomes, naturally occurring vesicles secreted by cells, are undergoing development as drug carriers. We used experimental and computational studies to investigate the kinetics of intracellular exosome processing and exosome-mediated drug efflux and the effects of exosome inhibition. The experiments used four human-breast or ovarian cancer cells, a cytotoxic drug paclitaxel (PTX), two exosome inhibitors (omeprazole (OME), which inhibits exosome release, and GW4869 (GW), which inhibits synthesis of sphingolipid ceramide required for exosome formation), LC-MS/MS analysis of PTX levels in exosomes, and confocal microscopic study of endocytic transport (monitored using fluorescent nanoparticles and endocytic organelle markers). In all four cells, exosome production was enhanced by PTX but diminished by OME or GW (p < 0.05); the PTX enhancement was completely reversed by OME or GW. Co-treatment with OME or GW simultaneously reduced PTX amount in exosomes and increased PTX amount and cytotoxicity in exosome-donor cells (corresponding to >2-fold synergy as indicated by curve shift and uncertainty envelope analyses). This synergy is consistent with the previous reports that OME co-administration significantly enhances the taxane activity in tumor-bearing mice and in patients with triple negative metastatic breast cancer. The experimental results were used to develop a quantitative pharmacology model; model simulations revealed the different effects of the two exosome inhibitors on intracellular PTX processing and subcellular distribution.

In Vitro Synergistic Inhibition of HT-29 Proliferation and 2H-11 and HUVEC Tubulogenesis by Bacopaside I and II Is Associated with Ca2+ Flux and Loss of Plasma Membrane Integrity

We previously showed how triterpene saponin bacopaside (bac) II, purified from the medicinal herb Bacopa monnieri, induced cell death in colorectal cancer cell lines and reduced endothelial cell migration and tube formation, and further demonstrated a synergistic effect of a combination of bac I and bac II on the inhibition of breast cancer cell line growth. Here, we assessed the effects of bac I and II on the colorectal cancer HT-29 cell line, and mouse (2H-11) and human umbilical vein endothelial cell (HUVEC) lines, measuring outcomes including cell viability, proliferation, migration, tube formation, apoptosis, cytosolic Ca²⁺ levels and plasma membrane integrity. Combined bac I and II, each applied at concentrations below IC₅₀ values, caused a synergistic reduction of the viability and proliferation of HT-29 and endothelial cells, and impaired the migration of HT-29 and tube formation of endothelial cells. A significant enhancement of apoptosis was induced only in HUVEC, although an increase in cytosolic Ca²⁺ was detected in all three cell lines. Plasma membrane integrity was compromised in 2H-11 and HUVEC, as determined by an increase in propidium iodide staining, which was preceded by Ca²⁺ flux. These in vitro findings support further research into the mechanisms of action of the combined compounds for potential clinical use.

Baicalein Inhibits Streptococcus mutans Biofilms and Dental Caries-Related Virulence Phenotypes

Dental caries, the most common oral disease, is a major public healthcare burden and affects more than three billion people worldwide. The contemporary understanding of the need for a healthy microbiome and the emergence of antimicrobial resistance has resulted in an urgent need to identify compounds that curb the virulence of pathobionts without microbial killing. Through this study, we have demonstrated for the first time that 5,6,7-trihydroxyflavone (Baicalein) significantly downregulates crucial caries-related virulence phenotypes in Streptococcus mutans. Baicalein significantly inhibited biofilm formation by Streptococcus mutans UA159 (MBIC50 = 200 μM), without significant growth inhibition. Notably, these concentrations of baicalein did not affect the commensal S. gordonii. Strikingly, baicalein significantly reduced cell surface hydrophobicity, autoaggregation and acid production by S. mutans. Mechanistic studies (qRT-PCR) showed downregulation of various genes regulating biofilm formation, surface attachment, quorum sensing, acid production and competence. Finally, we demonstrate the potential translational value of baicalein by reporting synergistic interaction with fluoride against S. mutans biofilms.

Transcriptomics analysis of hepatotoxicity induced by the pesticides imazalil, thiacloprid and clothianidin alone or in binary mixtures in a 28-day study in female Wistar rats

Co-occurrence of pesticide residues in food commodities raises a potential safety issue as their mixture effects on human health are largely unknown. In a previous study, we reported the toxicological effects (pathology and histopathology) of imazalil (IMZ), thiacloprid (THI), and clothianidin (CTD) alone and in binary mixtures in a 28-day oral gavage study in female Wistar rats. Five dose levels (up to 350 mg/kg body weight/day) ranging from a typical toxicological reference value to a clear effect dose were applied. In the present study, we undertook a transcriptomics analysis of rat livers by means of total RNA sequencing (RNA-Seq). Bioinformatic data analysis involving Ingenuity Pathway Analysis (IPA) was used to gain mechanistic information on hepatotoxicity-related pathways affected after treatment with the pesticides, alone and in mixtures. Our data show that 2986 genes were differentially regulated by CTD while IMZ and THI had effects on 194 and 225 genes, respectively. All three individual compounds shared a common subset of genes whose network is associated with xenobiotic metabolism and nuclear receptor activation. Similar networks were retrieved for the mixtures. Alterations in the expression of individual genes were in line with the assumption of dose addition. Our results bring new insight into the hepatotoxicity mechanisms of IMZ, THI, and CTD and their mixtures.

Identifying side effects of commonly used drugs in the treatment of Covid 19

To increase the success in Covid 19 treatment, many drug suggestions are presented, and some clinical studies are shared in the literature. There have been some attempts to use some of these drugs in combination. However, using more than one drug together may cause serious side effects on patients. Therefore, detecting drug-drug interactions of the drugs used will be of great importance in the treatment of Covid 19. In this study, the interactions of 8 drugs used for Covid 19 treatment with 645 different drugs and possible side effects estimates have been produced using Graph Convolutional Networks. As a result of the experiments, it has been found that the hematopoietic system and the cardiovascular system are exposed to more side effects than other organs. Among the focused drugs, Heparin and Atazanavir appear to cause more adverse reactions than other drugs. In addition, as it is known that some of these 8 drugs are used together in Covid-19 treatment, the side effects caused by using these drugs together are shared. With the experimental results obtained, it is aimed to facilitate the selection of the drugs and increase the success of Covid 19 treatment according to the targeted patient.

Rosmarinic acid exhibits broad anti-enterovirus A71 activity by inhibiting the interaction between the five-fold axis of capsid VP1 and cognate sulfated receptors

Enterovirus A71 (EV-A71), a positive-stranded RNA virus of the Picornaviridae family, may cause neurological complications or fatality in children. We examined specific factors responsible for this virulence using a chemical genetics approach. Known compounds from an anti-EV-A71 herbal medicine, Salvia miltiorrhiza (Danshen), were screened for anti-EV-A71. We identified a natural product, rosmarinic acid (RA), as a potential inhibitor of EV-A71 by cell-based antiviral assay and in vivo mouse model. Results also show that RA may affect the early stage of viral infection and may target viral particles directly, thereby interfering with virus-P-selectin glycoprotein ligand-1 (PSGL1) and virus-heparan sulfate interactions without abolishing the interaction between the virus and scavenger receptor B2 (SCARB2). Sequencing of the plaque-purified RA-resistant viruses revealed a N104K mutation in the five-fold axis of the structural protein VP1, which contains positively charged amino acids reportedly associated with virus-PSGL1 and virus-heparan sulfate interactions via electrostatic attraction. The plasmid-derived recombinant virus harbouring this mutation was confirmed to be refractory to RA inhibition. Receptor pull-down showed that this non-positively charged VP1-N104 is critical for virus binding to heparan sulfate. As the VP1-N104 residue is conserved among different EV-A71 strains, RA may be useful for inhibiting EV-A71 infection, even for emergent virus variants. Our study provides insight into the molecular mechanism of virus-host interactions and identifies a promising new class of inhibitors based on its antiviral activity and broad spectrum effects against a range of EV-A71.

Effect of Interaction between 17β-Estradiol, 2-Methoxyestradiol and 16α-Hydroxyestrone with Chromium (VI) on Ovary Cancer Line SKOV-3: Preliminary Study

Ovarian cancer is the leading cause of death from gynecologic malignancies. Some estrogens, as well as xenoestrogens, such as chromium (VI) (Cr(VI)), are indicated as important pathogenic agents. The objective of this study was to evaluate the role of estradiol and some its metabolites upon exposure to the metalloestrogen Cr(VI) in an in vitro model. The changes in cell viability of malignant ovarian cancer cells (SKOV-3 resistant to cisplatin) exposed to 17β-estradiol (E2) and its two metabolites, 2-methoxyestradiol (2-MeOE2) and 16α-hydroxyestrone (16α-OHE1), upon exposure to potassium chromate (VI) and its interactions were examined. The single and mixed models of action, during short and long times of incubation with estrogens, were applied. The different effects (synergism and antagonism) of estrogens on cell viability in the presence of Cr(VI) was observed. E2 and 16α-OHE1 caused a synergistic effect after exposure to Cr(VI). 2-MeOE2 showed an antagonistic effect on Cr(VI). The examined estrogens could be ranked according to the most protective effect or least toxicity in the order: 2-MeOE2 > E2 > 16α-OHE1. Early pre-incubation (24 h or 7 days) of cells with estrogens caused mostly an antagonistic effect-protective against the toxic action of Cr(VI). The beneficial action of estrogens on the toxic effect of Cr(VI), in the context of the risk of ovarian cancer, seems to be important and further studies are needed.

Evaluation of the Combination of Azithromycin and Naphthoquine in Animal Malaria Models

Combination therapy using drugs with different mechanisms of action is the current state of the art in antimalarial treatment. However, except for artemisinin-based combination therapies, only a few other combinations are now available. Increasing concern regarding the emergence and spread of artemisinin resistance in Plasmodium falciparum has led to a need for the development of new antimalarials. Moreover, the efficacy of current available chemoprophylaxis is compromised by drug resistance and noncompliance due to intolerable adverse effects or complicated dosing regimens.

Enhanced antitumor effect of alectinib in combination with cyclin-dependent kinase 4/6 inhibitor against RET-fusion-positive non-small cell lung cancer cells

Rearranged during transfection (RET) fusion-positive non-small cell lung cancer (NSCLC) accounts for 1% of lung adenocarcinoma. Although small molecule agents with RET kinase inhibitory activity such as alectinib, vandetanib, and cabozantinib have been clinically evaluated in RET-fusion-positive NSCLC, an effective monotherapy regimen has not been established. We explored agents to use in combination with alectinib to enhance the antitumor effect of alectinib against RET-fusion cells. Cell proliferation under co-treatment with alectinib plus each of six chemotherapeutic agents or six molecularly targeted agents was evaluated in vitro. The combination effect was analyzed by IC₅₀ isobologram and combination index using LC-2/ad and Ba/F3-KIF5B-RET cells. The in vivo combination effect was investigated in a Ba/F3-KIF5B-RET xenograft model. The phosphorylation levels of proteins regulating proliferation were measured by immunoblotting. Palbociclib, a CDK4/6 inhibitor, showed the greatest synergy against LC-2/ad cells in the isobologram analysis and combination index. This synergistic effect was also observed against Ba/F3-KIF5B-RET cells. Another CDK4/6 inhibitor, abemaciclib, also showed a synergistic effect. In vivo, the combination of alectinib plus palbociclib showed a more enhanced antitumor effect than each single agent in a mouse xenograft model with transplanted Ba/F3-KIF5B-RET cells. This combination suppressed the phosphorylation of S6 and Rb more intensely than did either single agent in both LC-2/ad and Ba/F3-KIF5B-RET cell lines, both in vitro and in vivo. Combination therapy with alectinib plus the CDK4/6 inhibitor enhanced the antitumor effect against RET-fusion-positive cells in vitro and in vivo.

Assessment of STAT5 as a potential therapy target in enzalutamide-resistant prostate cancer

Despite enzalutamide's efficacy in delaying the progression of metastatic castration-resistant prostate cancer (CRPC), resistance to this anti-androgen inevitably occurs. Several studies have revealed that the signal transducer and activator of transcription (STAT) 5 plays a role in tumour progression and development of drug resistance such as enzalutamide. Data mining revealed heterogeneous expression of STAT5 in enzalutamide-treated mCRPC patients and enzalutamide-resistant prostate cancer (PCa). Isobologram analysis revealed that the STAT5 inhibitor pimozide combined with enzalutamide has? additive and synergistic inhibitory effects on cell viability in the used models. Functional analysis with siRNA-mediated STAT5 knockdown yielded divergent results. The LNCaP-derived cell line MR49F could be resensitised to enzalutamide by siRNA-mediated STAT5b-knock-down. In contrast, neither STAT5a nor STAT5b knockdown resensitised enzalutamide-resistant LAPC4-EnzaR cells to enzalutamide. In conclusion, our results indicate that STAT5 may be a possible target in a subgroup of enzalutamide-resistant PCa. However, based on the data presented here, a general role of STAT5 in enzalutamide-resistance and its potential as a therapeutic target could not be shown.

An Artemisinin-Derivative-(NHC)Gold(I) Hybrid with Enhanced Cytotoxicity through Inhibition of NRF2 Transcriptional Activity

A family of hybrid complexes combining two biologically active motifs, an artemisinin derivative and a cationic bis(NHC)-gold(I) unit, has been synthesized. One of these complexes, 2 a, has been analyzed by single-crystal X-ray diffraction. 2 a shows strong anticancer activities on a large panel of human cancer cell models (prostate, breast, lung, liver, bladder, bone, acute and chronic myeloid leukemias) with GI₅₀ values in the nm range, together with a high selectivity. An original and distinctive mechanism of action, that is, through inhibition of the redox antioxidant NRF2 transcription factor (strongly associated with aggressiveness and resistance to cancer therapies) has been evidenced. 2 a could remarkably sensitize to sorafenib in HepG2 liver cells, in which dysregulated NRF2 signaling is linked to primary and acquired drug resistance. 2 a also inhibited NF-κB and HIF transcriptional activities, which are also associated with progression and resistance in cancer. Our findings provide evidence that hybrid (NHC)gold(I) compounds represent a new class of organometallic hybrid molecules that may yield new therapeutic agents.

Curcumin Sensitizes Kidney Cancer Cells to TRAIL-Induced Apoptosis via ROS Mediated Activation of JNK-CHOP Pathway and Upregulation of DR4

Tumour necrosis factor-related apoptosis-inducing ligand (TRAIL), is a selective anticancer cytokine capable of exerting a targeted therapy approach. Disappointingly, recent research has highlighted the development of TRAIL resistance in cancer cells, thus minimising its usefulness in clinical settings. However, several recent studies have demonstrated that cancer cells can be sensitised to TRAIL through the employment of a combinatorial approach, utilizing TRAIL in conjunction with other natural or synthetic anticancer agents. In the present study, the chemo-sensitising effect of curcumin on TRAIL-induced apoptosis in renal carcinoma cells (RCC) was investigated. The results indicate that exposure of kidney cancer ACHN cells to curcumin sensitised the cells to TRAIL, with the combination treatment of TRAIL and curcumin synergistically targeting the cancer cells without affecting the normal renal proximal tubular epithelial cells (RPTEC/TERT1) cells. Furthermore, this combination treatment was shown to induce caspase-dependent apoptosis, inhibition of the proteasome, induction of ROS, upregulation of death receptor 4 (DR4), alterations in mitogen-activated protein kinase (MAPK) signalling and induction of endoplasmic reticulum stress. An in vivo zebrafish embryo study demonstrated the effectiveness of the combinatorial regime to inhibit tumour formation without affecting zebrafish embryo viability or development. Overall, the results arising from this study demonstrate that curcumin has the ability to sensitise TRAIL-resistant ACHN cells to TRAIL-induced apoptosis.

Multilayer capsules encapsulating nimbin and doxorubicin for cancer chemo-photothermal therapy

Layer-by-layer (LbL) assembled poly(allylamine hydrochloride) (PAH) and poly(methacrylic acid) (PMA) microcapsules were designed to incorporate gold nanorods (NRs) and co-encapsulate and release two drugs for cancer therapy. Calcium carbonate (CaCO₃) microparticles modified with preformed NRs were used as sacrificial templates for the fabrication of hollow PAH/PMA/NR capsules incorporated with NRs. The hollow capsules were found to be 4.5 ± 0.5 µm in size and appeared with uniformly distributed NRs in the interior of the capsules. The morphology of the capsules transformed from pore free continuous structure to porous structure under laser light irradiation at 808 nm and 0.5 W cm^-2. The encapsulation experiments showed that the hydrophilic drug (doxorubicin hydrochloride, Dox) was encapsulated in the interior of the capsules while the hydrophobic drug (nimbin, NB) was entrapped in the porous polymeric network of the layer components. The encapsulation efficiency was found to be 30% for both Dox and NB. The release experiments showed an initial burst release followed by sustained release up to 3 h. Notably, the release was completed within 30 min under NIR irradiation at 808 nm. The estimated IC₅₀ values against THP-1 cells were 75 and 1.8 µM for NB and Dox, respectively. The dual drug loaded capsules showed excellent anticancer activity against THP-1 cells under NIR light exposure in in-vitro experiments. Thus, such remotely addressable dual-drug loaded capsules with the provision for encapsulation of natural drugs demonstrate high potential for use as theranostics in cancer therapy.

Cancer prevention and treatment using combination therapy with natural compounds

Introduction: Naturally occurring compounds play an essential role in the prevention and treatment of various cancers. There are more than 100 plant and animal based natural compounds currently in clinical use.Areas covered: 1) The importance of natural products combinations in the prevention and treatment of cancer, 2) the need to maximize efficacy while minimizing side effects when using natural product combinations, and 3) specifics related to plant and animal derived natural products, as well as agents derived from natural products. Therapies using natural compounds that have been investigated, their rationale, mechanism of action and findings are reviewed. When the data warrant it, combined interventions that appear to increase efficacy (compared with monotherapy) while minimizing toxicity have been highlighted. Pubmed was used to search for relevant publications.Expert opinion: Combination therapy with natural compounds has the potential to be more effective than single agent therapy. Similar to pharmacologic agents, the goal is to maximize efficacy while mimimizing potential side effects. There is an increasing research focus on the development of agents derived from natural products, with notable successes already achieved from the effort.

Effect of methyl jasmonate and 3-bromopyruvate combination therapy on mice bearing the 4 T1 breast cancer cell line

Cancer cells apply the Warburg pathway to meet their increased metabolic demands caused by their rapid growth and proliferation and also creates an acidic environment to promote cancer cell invasion. 3-bromopyruvate (3-BrP) as an anti-cancer agent disrupts glycolytic pathway. Moreover, one of the mechanism of actions of Methyl Jasmonate (MJ) is interference in glycolysis. Hence, the aim of this study was to evaluate MJ and 3-BrP interaction. MTT assay was used to determine IC50 and synergistic concentrations. Combination index was applied to evaluate the drug- drug interaction. Human tumor xenograft breast cancer mice was used to evaluate drug efficacy in vivo. Tumor size was considered as a drug efficacy criterion. In addition to drug efficacy, probable side effects of these drugs including hepatotoxicity, renal failure, immunotoxicity, and losing weight were evaluated. Serum alanine aminotransferase and aspartate aminotransferase for hepatotoxicity, serum urea and creatinine level for the possibility of renal failure and changes in body weight were measured to evaluate drug toxicity. IL10 and TGFβ secretion in supernatant of isolated splenocytes from treated mice were assessed to check immunotoxicity. 3-BrP synergistically augmented the efficacy of MJ in the specific concentrations. This polytherapy was more effective than monotherapy of 3-BrP, MJ, and also surprisingly cyclophosphamide as a routine treatment for breast cancer in the tumor bearing mice. These results have been shown by decrease in tumor volume and increase of tumor growth inhibition percentage. This combination therapy didn't have any noticeable side effects on kidney, liver, and immune system and body weight.

A Combination of Rosa Canina Extracts and Gold Complex Favors Apoptosis of Caco-2 Cells by Increasing Oxidative Stress and Mitochondrial Dysfunction

Given the alarming increase in colorectal cancer (CRC) worldwide, novel therapies are urgently needed. Plant-derived extracts have gained considerable interest in the last years due to their strong anticancer effect mediated by their unique bioactive compounds. Specifically, rosehips from Rosa canina have been successfully tested against several cancer models, including colon cancer. Moreover, gold derivatives are a promising alternative to the current platinum-based drugs commonly used in CRC chemotherapy due to their lack of affinity for DNA. Herein we have investigated the antitumor potential of a drug combination made of acidic polyphenols extracted from R. canina and the gold complex (Au(C≡C-2-NC₅H₄) (PTA)) in Caco-2 cell line as a model of CRC. The combination triggered strong apoptosis mediated by a blockage of the autophagic flux, which might be a consequence of a reactive oxygen species (ROS) increase and mitochondrial dysfunctionality. Our results suggest that the clinical application of plant polyphenols might enhance the anticancer effect of metallodrugs and reduce drug exposure time and therefore its side effects.

Bacopasides I and II Act in Synergy to Inhibit the Growth, Migration and Invasion of Breast Cancer Cell Lines

Bacopaside (bac) I and II are triterpene saponins purified from the medicinal herb Bacopa monnieri. Previously, we showed that bac II reduced endothelial cell migration and tube formation and induced apoptosis in colorectal cancer cell lines. The aim of the current study was to examine the effects of treatment with combined doses of bac I and bac II using four cell lines representative of the breast cancer subtypes: triple negative (MDA-MB-231), estrogen receptor positive (T47D and MCF7) and human epidermal growth factor receptor 2 (HER2) positive (BT-474). Drug treatment outcome measures included cell viability, proliferation, cell cycle, apoptosis, migration, and invasion assays. Relationships were analysed by one- and two-way analysis of variance with Bonferroni post-hoc analysis. Combined doses of bac I and bac II, each below their half maximal inhibitory concentration (IC50), were synergistic and reduced the viability and proliferation of the four breast cancer cell lines. Cell loss occurred at the highest dose combinations and was associated with G2/M arrest and apoptosis. Migration in the scratch wound assay was significantly reduced at apoptosis-inducing combinations, but also at non-cytotoxic combinations, for MDA-MB-231 and T47D (p < 0.0001) and BT-474 (p = 0.0003). Non-cytotoxic combinations also significantly reduced spheroid invasion of MDA-MB-231 cells by up to 97% (p < 0.0001). Combining bac I and II below their IC50 reduced the viability, proliferation, and migration and invasiveness of breast cancer cell lines, suggesting synergy between bac I and II.

Sorbus domestica Leaf Extracts and Their Activity Markers: Antioxidant Potential and Synergy Effects in Scavenging Assays of Multiple Oxidants

Sorbus domestica leaves are a traditionally used herbal medicine recommended for the treatment of oxidative stress-related diseases. Dry leaf extracts (standardized by LC-MS/MS and LC-PDA) and nine model activity markers (polyphenols), were tested in scavenging assays towards six in vivo-relevant oxidants (O2•-, OH•, NO•, H2O2, ONOO-, HClO). Ascorbic acid (AA) and Trolox (TX) were used as positive standards. The most active extracts were the diethyl ether and ethyl acetate fractions with activities in the range of 3.61-20.03 µmol AA equivalents/mg, depending on the assay. Among the model compounds, flavonoids were especially effective in OH• scavenging, while flavan-3-ols were superior in O2•- quenching. The most active constituents were quercetin, (-)-epicatechin, procyanidins B2 and C1 (3.94-24.16 µmol AA/mg), but considering their content in the extracts, isoquercitrin, (-)-epicatechin and chlorogenic acid were indicated as having the greatest influence on extract activity. The analysis of the synergistic effects between those three compounds in an O2•- scavenging assay demonstrated that the combination of chlorogenic acid and isoquercitrin exerts the greatest influence. The results indicate that the extracts possess a strong and broad spectrum of antioxidant capacity and that their complex composition plays a key role, with various constituents acting complementarily and synergistically.

Synergy and antagonism in natural product extracts: when 1 + 1 does not equal 2

Covering: 2000 to 2019 According to a 2012 survey from the Centers for Disease Control and Prevention, approximately 18% of the U.S. population uses natural products (including plant-based or botanical preparations) for treatment or prevention of disease. The use of plant-based medicines is even more prevalent in developing countries, where for many they constitute the primary health care modality. Proponents of the medicinal use of natural product mixtures often claim that they are more effective than purified compounds due to beneficial "synergistic" interactions. A less-discussed phenomenon, antagonism, in which effects of active constituents are masked by other compounds in a complex mixture, also occurs in natural product mixtures. Synergy and antagonism are notoriously difficult to study in a rigorous fashion, particularly given that natural products chemistry research methodology is typically devoted to reducing complexity and identifying single active constituents for drug development. This report represents a critical review with commentary about the current state of the scientific literature as it relates to studying combination effects (including both synergy and antagonism) in natural product extracts. We provide particular emphasis on analytical and Big Data approaches for identifying synergistic or antagonistic combinations and elucidating the mechanisms that underlie their interactions. Specific case studies of botanicals in which synergistic interactions have been documented are also discussed. The topic of synergy is important given that consumer use of botanical natural products and associated safety concerns continue to garner attention by the public and the media. Guidance by the natural products community is needed to provide strategies for effective evaluation of safety and toxicity of botanical mixtures and to drive discovery in botanical natural product research.

5-Oxo-1-[(2,3,6,7-tetramethoxy-9-phenanthrenyl)methyl]-L-proline Inhibits Hepatitis C Virus Entry

Hepatitis C virus (HCV) is the major causative agent of chronic liver diseases, including liver cirrhosis and hepatocellular carcinoma. The recent development of highly effective direct-acting antivirals (DAAs) has revolutionized the treatment of HCV patients. However, these DAAs are exorbitantly expensive for the majority of HCV patients worldwide. Moreover, these drugs still show genotypic difference in cure rate and have some resistant-associated variants. Tylophorine, a natural compound derived from Tylophora indica plants, is known to have anti-inflammatory and anti-cancerous growth activities. In the present study, we showed that two tylophorine intermediates, 5-Oxo-1-[(2,3,6,7-tetramethoxy-9-phenanthrenyl) methyl]-L-proline (O859585) and 2,3,6,7-tetramethoxy-9-phenanthrenecarboxylic acid (T298875), displayed anti-HCV activity with an EC₅₀ of 38.25 µM for T298875 and 29.11~35.3 µM for O859585 in various HCV genotypes. We demonstrated that O859585 efficiently blocked HCV attachment by neutralizing free viral particles without affecting other stages of the HCV life cycle and interferon stimulation. O859585 interrupted binding between HCV E2 and CD81. Of note, co-treatment of O859585 with either interferon alpha (IFNα) or sofosbuvir exerted either an additive or synergistic antiviral activity in HCV-infected cells with no measurable effect on cell viability. Most importantly, O859585 in combination with IFNα and sofosbuvir exhibited synergistic effects on anti-HCV activity in primary human hepatocytes. Collectively, these data suggest that O859585 may be a novel antiviral agent for HCV therapy.

4,5-Diaryl 3(2H)Furanones: Anti-Inflammatory Activity and Influence on Cancer Growth

Apart from their anti-inflammatory action, COX inhibitors have gathered the interest of many scientists due to their potential use for the treatment and prevention of cancer. It has been shown that cyclooxygenase inhibitors restrict cancer cell growth and are able to interact with known antitumor drugs, enhancing their in vitro and in vivo cytotoxicity. The permutation of hydrophilic and hydrophobic aryl groups in COX inhibitors leads to cardinal changes in the biological activity of the compounds. In the present study, thirteen heterocyclic coxib-like 4,5-diarylfuran-3(2H)-ones and their annelated derivatives—phenanthro[9,10-b]furan-3-ones—were synthesized and studied for anti-inflammatory and COX-1/2 inhibitory action and for their cytotoxic activity on the breast cancer (MCF-7) and squamous cell carcinoma (HSC-3) cell lines. The F-derivative of the –SOMe substituted furan-3(2H)-ones exhibited the best activity (COX-1 IC₅₀ = 2.8 μM, anti-inflammatory activity (by carrageenan paw edema model) of 54% (dose 0.01 mmol/kg), and MCF-7 and HSC-3 cytotoxicity with IC₅₀ values of 10 μM and 7.5 μM, respectively). A cytotoxic effect related to the COX-1 inhibitory action was observed and a synergistic effect with the anti-neoplastic drugs gefitinib and 5-fluorouracil was found. A phenanthrene derivative exhibited the best synergistic effect with gefitinib.

Inhibition of aerobic glycolysis enhances the anti-tumor efficacy of Zoptarelin Doxorubicin in triple-negative breast cancer cells

AIM

A characteristic of cancer cells including triple-negative breast cancers (TNBC) is an increased aerobic glycolysis for ATP production representing a selective therapeutic target. More than 70% of TNBC express gonadotropin-releasing hormone receptors (GnRH-R). These receptors can be used for targeted chemotherapy with cytotoxic GnRH agonists such as Zoptarelin Doxorubicin, in which doxorubicin is covalently linked to [D-Lys⁶ ]GnRH. In this study, we have analyzed whether inhibition of aerobic glycolysis can enhance the antitumor efficacy of GnRH-R-targeted chemotherapy using Zoptarelin Doxorubicin.

METHODS

Triple-negative breast cancers cell lines MDA-MB-231 and HCC1806 were treated with Zoptarelin Doxorubicin, glycolysis inhibitor 2-deoxy-D-glucose (2DG) or the combination of both agents. Cell viability was measured using Alamar blue. Induction of apoptosis was quantified by measurement of loss of mitochondrial membrane potential. In vivo experiments were performed using nude mice bearing xenografted MDA-MB-231 tumors.

RESULTS

Treatment of TNBC cells with Zoptarelin Doxorubicin or with 2DG resulted in a significant decrease of cell viability and a significant increase of apoptosis. Treatment with Zoptarelin Doxorubicin in combination with 2DG resulted in significantly reduced viability and enhanced apoptosis compared with single-agent treatments. Combinational index (CI) analysis revealed the co-treatment effect as a synergistic. The antitumor effects of Zoptarelin Doxorubicin or 2DG were confirmed in nude mice. The tumor reducing effects of Zoptarelin Doxorubicin were enhanced by combination with 2DG.

CONCLUSION

The glycolytic phenotype of TNBC can be used to improve antitumor therapies. Co-treatment of Zoptarelin Doxorubicin with glycolysis inhibitor 2DG might be a suitable therapeutic option for GnRH receptor-positive TNBC.

Allosteric Modulators of Sigma-1 Receptor: A Review

Allosteric modulators of sigma-1 receptor (Sig1R) are described as compounds that can increase the activity of some Sig1R ligands that compete with (+)-pentazocine, one of the classic prototypical ligands that binds to the orthosteric Sig1R binding site. Sig1R is an endoplasmic reticulum membrane protein that, in addition to its promiscuous high-affinity ligand binding, has been shown to have chaperone activity. Different experimental approaches have been used to describe and validate the activity of allosteric modulators of Sig1R. Sig1R-modulatory activity was first found for phenytoin, an anticonvulsant drug that primarily acts by blocking the voltage-gated sodium channels. Accumulating evidence suggests that allosteric Sig1R modulators affect processes involved in the pathophysiology of depression, memory and cognition disorders as well as convulsions. This review will focus on the description of selective and non-selective allosteric modulators of Sig1R, including molecular structure properties and pharmacological activity both in vitro and in vivo, with the aim of providing the latest overview from compound discovery approaches to eventual clinical applications. In this review, the possible mechanisms of action will be discussed, and future challenges in the development of novel compounds will be addressed.

Statistical assessment and visualization of synergies for large-scale sparse drug combination datasets

BACKGROUND

Drug combinations have the potential to improve efficacy while limiting toxicity. To robustly identify synergistic combinations, high-throughput screens using full dose-response surface are desirable but require an impractical number of data points. Screening of a sparse number of doses per drug allows to screen large numbers of drug pairs, but complicates statistical assessment of synergy. Furthermore, since the number of pairwise combinations grows with the square of the number of drugs, exploration of large screens necessitates advanced visualization tools.

RESULTS

We describe a statistical and visualization framework for the analysis of large-scale drug combination screens. We developed an approach suitable for datasets with large number of drugs pairs even if small number of data points are available per drug pair. We demonstrate our approach using a systematic screen of all possible pairs among 108 cancer drugs applied to melanoma cell lines. In this dataset only two dose-response data points per drug pair and two data points per single drug test were available. We used a Bliss-based linear model, effectively borrowing data from the drug pairs to obtain robust estimations of the singlet viabilities, consequently yielding better estimates of drug synergy. Our method improves data consistency across dosing thus likely reducing the number of false positives. The approach allows to compute p values accounting for standard errors of the modeled singlets and combination viabilities. We further develop a synergy specificity score that distinguishes specific synergies from those arising with promiscuous drugs. Finally, we developed a summarized interactive visualization in a web application, providing efficient access to any of the 439,000 data points in the combination matrix ( http://www.cmtlab.org:3000/combo_app.html ). The code of the analysis and the web application is available at https://github.com/arnaudmgh/synergy-screen .

CONCLUSIONS

We show that statistical modeling of single drug response from drug combination data can help determine significance of synergy and antagonism in drug combination screens with few data point per drug pair. We provide a web application for the rapid exploration of large combinatorial drug screen. All codes are available to the community, as a resource for further analysis of published data and for analysis of other drug screens.

The Phenolic compound Kaempferol overcomes 5-fluorouracil resistance in human resistant LS174 colon cancer cells

Resistance to 5-Fluorouracil chemotherapy is a major cause of therapeutic failure in colon cancer cure. Development of combined therapies constitutes an effective strategy to inhibit cancer cells and prevent the emergence of drug resistance. For this purpose, we investigated the anti-tumoral effect of thirteen phenolic compounds, from the Tunisian quince Cydonia oblonga Miller, alone or combined to 5-FU, on the human 5-FU-resistant LS174-R colon cancer cells in comparison to parental cells. Our results showed that only Kaempferol was able to chemo-sensitize 5-FU-resistant LS174-R cells. This phenolic compound combined with 5-FU exerted synergistic inhibitory effect on cell viability. This combination enhanced the apoptosis and induced cell cycle arrest of both chemo-resistant and sensitive cells through impacting the expression levels of different cellular effectors. Kaempferol also blocked the production of reactive oxygen species (ROS) and modulated the expression of JAK/STAT3, MAPK, PI3K/AKT and NF-κB. In silico docking analysis suggested that the potent anti-tumoral effect of Kaempferol, compared to its two analogs (Kaempferol 3-O-glucoside and Kampferol 3-O-rutinoside), can be explained by the absence of glucosyl groups. Overall, our data propose Kaempferol as a potential chemotherapeutic agent to be used alone or in combination with 5-FU to overcome colon cancer drug resistance.

Mechanisms and the clinical relevance of complex drug-drug interactions

As a result of an increasing aging population, the number of individuals taking multiple medications simultaneously has grown considerably. For these individuals, taking multiple medications has increased the risk of undesirable drug–drug interactions (DDIs), which can cause serious and debilitating adverse drug reactions (ADRs). A comprehensive understanding of DDIs is needed to combat these deleterious outcomes. This review provides a synopsis of the pharmacokinetic (PK) and pharmacodynamic (PD) mechanisms that underlie DDIs. PK-mediated DDIs affect all aspects of drug disposition: absorption, distribution, metabolism and excretion (ADME). In this review, the cells that play a major role in ADME and have been investigated for DDIs are discussed. Key examples of drug metabolizing enzymes and drug transporters that are involved in DDIs and found in these cells are described. The effect of inhibiting or inducing these proteins through DDIs on the PK parameters is also reviewed. Despite most DDI studies being focused on the PK effects, DDIs through PD can also lead to significant and harmful effects. Therefore, this review outlines specific examples and describes the additive, synergistic and antagonistic mechanisms of PD-mediated DDIs. The effects DDIs on the maximum PD response (E_max) and the drug dose or concentration (EDEC₅₀) that lead to 50% of E_max are also examined. Significant gaps in our understanding of DDIs remain, so innovative and emerging approaches are critical for overcoming them.

Combination of lutetium-177 labelled anti-L1CAM antibody chCE7 with the clinically relevant protein kinase inhibitor MK1775: a novel combination against human ovarian carcinoma

Background

Protein kinase inhibitors (PKIs) are currently tested in clinical studies (phase I-III) as an alternative strategy against (recurrent) ovarian cancer. Besides their anti-tumour efficacy, several PKIs have also shown radiosensitizing effects when combined with external beam radiation. Based on these results we asked if the addition of PKIs offers a therapeutic opportunity to improve radioimmunotherapy (RIT) against ovarian cancer. Five PKIs (alisertib, MK1775, MK2206, saracatinib, temsirolimus) were chosen for cytotoxicity screenings based on their current clinical trials in the treatment of ovarian cancer and their influence on cell cycle regulation and DNA damage repair pathways. We combined selected PKIs with ¹⁷⁷Lu-labelled anti-L1CAM monoclonal antibody chCE7 for our investigations.

Methods

PKIs cytotoxicity was determined via cell colony-forming assays. Biomarker of DNA double-strand breaks (DSBs, γH2A.X) was analysed by western blot and fluorescence microscopy. Flow cytometric measurements were performed to evaluate levels of apoptosis based on mono- or combination treatments. The best combination was used for in vivo combination therapy studies in nude mice with SKOV3ip and IGROV1 human ovarian cancer xenografts. Bonferroni correction was used to determine statistical significance for multiple comparisons.

Results

The highest cytotoxicity against both cell lines was observed for MK1775 and alisertib. Combinations including ¹⁷⁷Lu-labelled mAb chCE7 and MK1775 decreased ¹⁷⁷Lu-DOTA-chCE7 IC₆₀-values 14-fold, compared to 6-fold, when the radioimmunoconjugate was combined with alisertib. The most effective PKI MK1775 was further evaluated and demonstrated synergistic effects in combination with ¹⁷⁷Lu-DOTA-chCE7 against IGROV1 cells. Significantly higher amounts of DSBs were detected in IGROV1 cells after combination (91%) compared to either treatment alone (MK1775: 52%; radioimmunoconjugate: 72%; p < 0.0125). Early-apoptosis was significantly enhanced in IGROV1 cells correlating with induced DSBs (¹⁷⁷Lu-DOTA-chCE7: 8%, MK1775: 28%, ¹⁷⁷Lu-DOTA-chCE7 + MK1775: 40%, p < 0.0125). Immunohistochemistry analysis of γH2A.X expression levels after therapy in SKOV3ip xenografts revealed a high sensitivity of the tumour cells to MK1775 and a high radioresistance. A prominent effect of tumour growth inhibition of the RIT and of the combination therapy was observed in vivo in a late stage IGROV1 xenograft model.

Conclusions

Our results warrant further evaluation of combination of MK1775 and radioimmunotherapy.

Electronic supplementary material

The online version of this article (10.1186/s12885-018-4836-1) contains supplementary material, which is available to authorized users.

The role of miRNAs 34a, 146a, 320a and 542 in the synergistic anticancer effects of methyl 2-(5-fluoro-2-hydroxyphenyl)-1H- benzo[d]imidazole-5-carboxylate (MBIC) with doxorubicin in breast cancer cells

Combination Index (CI) analysis suggested that MBIC and doxorubicin synergistically inhibited up to 97% of cell proliferation in ER⁺/PR⁺MCF-7 and triple negative MDA-MB-231 breast cancer cell lines. Moreover, treatment of the breast cancer cells with the combined drugs resulted in lower IC₅₀ values in contrast to the individual drug treatment. Small noncoding microRNAs (miRNA) may function as non-mutational gene regulators at post-transcriptional level of protein synthesis. In the present study, the effect of the combined treatment of MBIC and doxorubicin on the expression level of several miRNAs including miR-34a, miR-146a, miR-320a and miR-542 were evaluated in MCF-7 and MDA-MB-231 breast cancer cell lines. These miRNAs have the potential to alter the protein level of survivin, the anti-apoptotic protein and reduce the metastatic activity in human breast cancer cell lines by interfering with the nuclear accumulation of NF-κB. Our results demonstrated the several fold changes in expression of miRNAs, which is drug and cell line dependent. This finding demonstrated a functional synergistic network between miR-34a, miR-320a and miR-542 that are negatively involved in post-transcriptional regulation of survivin in MCF-7 cells. While in MDA-MB-231 cells, changes in expression level of miR-146a was correlated with inhibition of the nuclear translocation of NF-κB. The overall result suggested that alteration in protein level and location of survivin and NF-κB by miR-34a, miR-320a, miR-146a and miR-542, remarkably influenced the synergistic enhancement of combined MBIC and doxorubicin in treatment of aggressive and less aggressive human breast cancer cell lines.