FDA-approved Compounds Research Articles

Topoisomerase II as a Novel Antiviral Target against Panarenaviral Diseases.

Although many arenaviruses cause severe diseases with high fatality rates each year, treatment options are limited to off-label use of ribavirin, and a Food and Drug Administration (FDA)-approved vaccine is not available. To identify novel therapeutic candidates against arenaviral diseases, an RNA polymerase I-driven minigenome (MG) expression system for Lassa virus (LASV) was developed and optimized for high-throughput screening (HTS). Using this system, we screened 2595 FDA-approved compounds for inhibitors of LASV genome replication and identified multiple compounds including pixantrone maleate, a topoisomerase II inhibitor, as hits. Other tested topoisomerase II inhibitors also suppressed LASV MG activity. These topoisomerase II inhibitors also inhibited Junin virus (JUNV) MG activity and effectively limited infection by the JUNV Candid #1 strain, and siRNA knockdown of both topoisomerases (IIα and IIβ) restricted JUNV replication. These results suggest that topoisomerases II regulate arenavirus replication and can serve as molecular targets for panarenaviral replication inhibitors.

Machine learning driven drug repurposing strategy for identification of potential RET inhibitors against non-small cell lung cancer

Non-small cell lung cancer (NSCLC) remains the leading cause of mortality and morbidity worldwide accounting about 85% of total lung cancer cases. The receptor REarranged during Transfection (RET) plays an important role by ligand independent activation of kinase domain resulting in carcinogenesis. Presently, the treatment for RET driven NSCLC is limited to multiple kinase inhibitors. This situation necessitates the discovery of novel and potent RET specific inhibitors. Thus, we employed high throughput screening strategy to repurpose FDA approved compounds from DrugBank comprising of 2509 molecules. It is worth noting that the initial screening is accomplished with the aid of in-house machine learning model built using IC50 values corresponding to 2854 compounds obtained from BindingDB repository. A total of 497 compounds (19%) were predicted as actives by our generated model. Subsequent in silico validation process such as molecular docking, MMGBSA and density function theory analysis resulted in identification of two lead compounds named DB09313 and DB00471. The simulation study highlights the potency of DB00471 (Montelukast) as potential RET inhibitor among the investigated compounds. In the end, the half-minimal inhibitory activity of montelukast was also predicted against RET protein expressing LC-2/ad cell lines demonstrated significant anticancer activity. Collective analysis from our study highlights that montelukast could be a promising candidate for the management of RET specific NSCLC.

Transient regulation of RNA methylation in human hematopoietic stem cells promotes their homing and engraftment

Enhancing the efficiency of hematopoietic stem cell (HSC) homing and engraftment is critical for cord blood (CB) hematopoietic cell transplantation (HCT). Recent studies indicate that N6-methyladenosine (m6A) modulates the expression of mRNAs that are critical for stem cell function by influencing their stability. Here, we demonstrate that inhibition of RNA decay by regulation of RNA methylation, enhances the expression of the homing receptor chemokine C-X-C receptor-4 (CXCR4) in HSCs. We show that YTH N6-methyladenosine RNA binding protein 2 (YTHDF2), a m6A reader and FTO α-ketoglutarate dependent dioxygenase (FTO), a m6A eraser play an opposite role in this process. Through screening, we identified several FDA-approved compounds that regulate the expression of YTHDF2 and FTO in CB CD34+ cells. We show that transient downregulation of YTHDF2 or activation of FTO by using these compounds inhibits CXCR4 decay in CB HSCs and promotes their homing and engraftment. Our results demonstrate a novel regulation strategy to enhance the function of CB HSCs and provide a translational approach to enhance the clinical efficacy of HCT.

Fluorinated triphenylphosphonium analogs improve cell selectivity and invivo detection of mito-metformin.

Triphenylphosphonium (TPP+) conjugated compounds selectively target cancercells by exploiting their hyperpolarized mitochondrial membrane potential. Todate, studies have focused on modifying either the linker or the cargo of TPP+-conjugated compounds. Here, we investigated the biological effects ofdirect modification to TPP+ to improve the efficacy and detection of mito-metformin (MMe), a TPP+-conjugated probe we have shown to have promising preclinical efficacy against solid cancer cells. We designed, synthesized, and tested trifluoromethyl and methoxy MMe analogs (pCF3-MMe, mCF3-MMe, and pMeO-MMe) against multiple distinct human cancer cells. pCF3-MMe showed enhanced selectivity toward cancer cells compared to MMe, while retaining thesame signaling mechanism. Importantly, pCF3-MMe allowed quantitative monitoring of cellular accumulation via 19F-NMR invitro and invivo. Furthermore, adding trifluoromethyl groups to TPP+ reduced toxicity invivo while retaining anti-tumor efficacy, opening an avenue to de-risk these next-generation TPP+-conjugated compounds.

A multi-reference poly-conformational method for in silico design, optimization, and repositioning of pharmaceutical compounds illustrated for selected SARS-CoV-2 ligands.

This work presents a novel computational multi-reference poly-conformational algorithm for design, optimization, and repositioning of pharmaceutical compounds. The algorithm searches for candidates by comparing similarities between conformers of the same compound and identifies target compounds, whose conformers are collectively close to the conformers of each compound in the reference set. Reference compounds may possess highly variable MoAs, which directly, and simultaneously, shape the properties of target candidate compounds. The algorithm functionality has been case study validated in silico, by scoring ChEMBL drugs against FDA-approved reference compounds that either have the highest predicted binding affinity to our chosen SARS-CoV-2 targets or are confirmed to be inhibiting such targets in-vivo. All our top scoring ChEMBL compounds also turned out to be either high-affinity ligands to the chosen targets (as confirmed in separate studies) or show significant efficacy, in-vivo, against those selected targets. In addition to method case study validation, in silico search for new compounds within two virtual libraries from the Enamine database is presented. The library's virtual compounds have been compared to the same set of reference drugs that we used for case study validation: Olaparib, Tadalafil, Ergotamine and Remdesivir. The large reference set of four potential SARS-CoV-2 compounds has been selected, since no drug has been identified to be 100% effective against the virus so far, possibly because each candidate drug was targeting only one, particular MoA. The goal here was to introduce a new methodology for identifying potential candidate(s) that cover multiple MoA-s presented within a set of reference compounds.

EXTH-88. DOCETAXEL TARGETS AGGRESSIVE METHYLATION PROFILES AND SERVES AS A RADIOSENSITIZER IN HIGH-RISK MENINGIOMAS

Abstract DNA methylation profiling has emerged as a transformative prognostic tool in meningiomas, identifying distinct epigenetic subgroups that share unique clinical and biological features. Hypothesizing that methylation patterns may also reflect underlying pathogenic mechanisms, we investigated if this modality could be informative for the selection of efficacious chemotherapies in meningiomas, focusing on FDA-approved compounds that are well-tolerated in patients. Using a methylation dataset of 210 tumors, we identified 981 genes in which adjacent CpG sites were predictive of progression-free survival. Pathway enrichment of these genes nominated Docetaxel as a candidate therapeutic; a well-established taxane that is routinely used for breast, prostate, and lung cancers. Using 15 primary patient-derived cultures and 2 cell lines, we found that Docetaxel could inhibit meningioma growth at concentrations that were favorable relative to other cancers. This drug triggered apoptosis in meningiomas of all tumor grades and methylation classes, with IC50 values ranging from 0.8nm to 4.4nm in vitro. Combining Docetaxel with radiation therapy resulted in synergistic cytotoxic effects on meningioma cultures, associated with elevated markers of cell death and dsDNA breaks. We confirmed our results via orthotopic meningioma mouse models of the cell lines CH157 and IOMM-Lee, which exhibited dose-dependent improvements in mortality and tumor volume in response to Docetaxel and radiation. Our results leverage DNA methylation patterns to repurpose FDA-approved medications in the treatment of meningiomas, and suggest a clinical trial of Docetaxel with radiotherapy may be efficacious in higher-grade lesions.

Targeting notch signaling pathway in breast cancer stem cells through drug repurposing approach.

Breast cancer is recognized globally as one of the leading causes of malignant morbidity. It is a heterogeneous disease that accounts for 30 percent of all women diagnosed with cancer. To bring an anti-cancer drug from the bench to the bedside is an expensive and time-consuming process. The drug repurposing approach targets new enemies (new diseases) with old weapons (known drugs). The present study identified an FDA-approved drug targeting the γ-secretase complex involved in the Notch signaling pathway in breast cancer stem cells (BCSCs). A literature survey and in-silico study identified Venetoclax as a γ-secretase inhibitor (GSI) from 1615 FDA-approved drug compounds. In-silico docking potential of Venetoclax was better than the standard γ-secretase inhibitor RO4929097. Also, the molecular dynamics simulations of 200ns confirmed the stability of the Venetoclax-γ-secretase complex. These findings suggest that the use of Venetoclax represents a potential γ-secretase inhibitor in breast cancer stem cells. Eventually, the in vitro and clinical evaluation will be needed to confirm the potential chemopreventive and treatment effects of Venetoclax against breast cancer and breast cancer stem cells. Venetoclax appeared as the most promising drug of the 1615 FDA-approved drugs. Our in-silico findings suggest that Venetoclax may act as a γ-secretase inhibitor against the Notch signaling pathway in breast cancer stem cells.

Pixantrone Sensitizes Gram-Negative Pathogens to Rifampin.

The emergence of bacterial drug resistance poses a severe threat to global public health. In particular, antimicrobial-resistant pathogens lead to a high rate of treatment failure and significantly increase mortality. Repurposing FDA-approved compounds to sensitize superbugs to conventional antibiotics provides a promising strategy to alleviate such crises. Pixantrone (PIX) has been approved for treating aggressive B-cell non-Hodgkin's lymphoma. By high-throughput drug screening, we profiled the synergistic activity between PIX and rifampin (RFP) against Gram-negative extensively drug-resistant isolates by checkerboard assay. Mechanistic studies demonstrated that PIX impacted the flagellum assembly, induced irreversible intracellular reactive oxygen species accumulation and disrupted proton motive force. In addition, the combination of PIX with RFP possesses effective antimicrobial activity against multidrug-resistant strains in vivo without detected toxicity. Collectively, these results reveal the potential of PIX in combination with RFP as a therapy option for refractory infections caused by Gram-negative pathogens. IMPORTANCE Bacterial resistance has become increasingly serious because of the widespread use and abuse of antibiotics. In particular, the emergence of multidrug-resistant bacteria has posed a serious threat to human public health. Drug repurposing, the process of finding new uses for existing drugs, provide a promising pathway to solve antimicrobial resistance. Compared to the development of novel antibiotics, this strategy leverages well-characterized pharmacology and toxicology of known drugs and is more cost-effective.

Biological screening of a unique drug library targeting MRGPRX2.

Allergic drug reaction or drug allergy is an immunologically mediated drug hypersensitivity reaction (DHR). G-protein coupled receptors (GPCRs) are common drug targets and communicate extracellular signals that initiate cellular responses. Recent evidence shows that GPCR MRGPRX2 is of major importance in IgE-independent pseudo-allergic DHRs based on the suspected interactions between many FDA-approved peptidergic compounds and MRGPRX2. Our aim was to uncover novel MRGPRX2-selective and -potent agonists as drug candidates responsible for clinical features of pseudo-allergic DHRs. We conducted a primary high-throughput screening (HTS), coupled with mutagenesis targeting the MRGPRX2 N62S mutation, on a panel of 3,456 library compounds. We discovered pharmacologically active hit compounds as agonists of the MRGPRX2 protein according to high degrees of potency evaluated by the calcium response and validated by the degranulation assay. Using the molecular tool Forge, we also characterized the structure-activity relationship shared by identified hit compounds. The alternative allele of single nucleotide polymorphism rs10833049 (N62S) in MRGPRX2 demonstrated loss-of-function property in response to substance P and antineoplastic agent daunorubicin hydrochloride. We applied a unique assay system targeting the N62S mutation to the HTS and identified 84 MRGPRX2-selective active hit compounds representing diverse classes according to primary drug indications. The top five highly represented groups included fluoroquinolone and non-fluoroquinolone antibiotics; antidepressive/antipsychotic; antihistaminic and antineoplastic agents. We classified hit compounds into 14 clusters representing a variety of chemical and drug classes beyond those reported, such as opioids, neuromuscular blocking agents, and fluoroquinolones. We further demonstrated MRGPRX2-dependent degranulation in the human mast cell line LAD2 cells induced by three novel agonists representing the non-fluoroquinolone antibiotics (bacitracin A), anti-allergic agents (brompheniramine maleate) and tyrosine-kinase inhibitors (imatinib mesylate). Our findings could facilitate the development of interventions for personalized prevention and treatment of DHRs, as well as future pharmacogenetic investigations of MRGPRX2 in relevant disease cohorts.

High-content, arrayed compound screens with rhinovirus, influenza A virus and herpes simplex virus infections

Viruses are genetically and structurally diverse, and outnumber cells by orders of magnitude. They can cause acute and chronic infections, suppress, or exacerbate immunity, or dysregulate survival and growth of cells. To identify chemical agents with pro- or antiviral effects we conducted arrayed high-content image-based multi-cycle infection screens of 1,280 mainly FDA-approved compounds with three human viruses, rhinovirus (RV), influenza A virus (IAV), and herpes simplex virus (HSV) differing in genome organization, composition, presence of an envelope, and tropism. Based on Z’-factors assessing screening quality and Z-scores ranking individual compounds, we identified potent inhibitors and enhancers of infection: the RNA mutagen 5-Azacytidine against RV-A16; the broad-spectrum antimycotic drug Clotrimazole inhibiting IAV-WSN; the chemotherapeutic agent Raltitrexed blocking HSV-1; and Clobetasol enhancing HSV-1. Remarkably, the topical antiseptic compound Aminacrine, which is clinically used against bacterial and fungal agents, inhibited all three viruses. Our data underscore the versatility and potency of image-based, full cycle virus propagation assays in cell-based screenings for antiviral agents.

High-throughput small molecule screen identifies inhibitors of microsporidia invasion and proliferation in C. elegans.

Microsporidia are a diverse group of fungal-related obligate intracellular parasites that infect most animal phyla. Despite the emerging threat that microsporidia represent to humans and agricultural animals, few reliable treatment options exist. Here, we develop a high-throughput screening method for the identification of chemical inhibitors of microsporidia infection, using liquid cultures of Caenorhabditis elegans infected with the microsporidia species Nematocida parisii. We screen a collection of 2560 FDA-approved compounds and natural products, and identify 11 candidate microsporidia inhibitors. Five compounds prevent microsporidia infection by inhibiting spore firing, whereas one compound, dexrazoxane, slows infection progression. The compounds have in vitro activity against several other microsporidia species, including those known to infect humans. Together, our results highlight the effectiveness of C. elegans as a model host for drug discovery against intracellular pathogens, and provide a scalable high-throughput system for the identification and characterization of microsporidia inhibitors.

P062 Identification of Octenidine (dihydrochloride) inhibiting fungal filamentation by the repurposing approach

Poster session 1, September 21, 2022, 12:30 PM - 1:30 PMObjectivesHyphal formation is an important virulence factor of opportunistic pathogenic fungi and plays a vital role in invasive fungal infections. Therefore, hyphae can act as a specific target against invasive fungal infections and it is a new attempt to focus on identification of compounds inhibiting hyphal growth. Amphotericin B has potent inhibitory effect on the growth of hyphae, but its high toxicity limits its clinical use. To address this question, we performed a high-throughput screen of an FDA-approved compound library (HY-L022, MCE®) to identify compounds with mycelial inhibitory function.MethodsWe performed a high-throughput screen of an FDA-approved compounds library to identify potentially novel compounds for inhibiting hyphal growth and used amphotericin B (1.56 μm) as a positive control drug. The screening schematic is shown in Figure 1a. Firstly, we investigated the mycelial inhibitory activity of each compound at 100 μm in RPMI 1640 medium with Candida albicans SN152 strain. Secondly, micro checkboard dilution method was applied to determine the minimum hyphae-inhibiting concentration of compounds. The compound being included in the next round could inhibit the hyphal formation when its concentration was ≤12.5 μm. Lastly, we expanded medium to YPD containing 10% FBS, YPD containing 5 mm N-acetylglucosamine (GlcNAc), and Spider medium. The final Candidate compound was determined due to its minimum hyphae-inhibiting concentration was ≤3.125 μm in four mediums.ResultsWe screened a library of FDA-approved compound and identified 117 Candidate compounds that inhibit hyphal growth (≤100 μm). We excluded 14 compounds with known antifungal activity, and finally 103 compounds were included in the next step of mycelial inhibitory activity screening (Fig. 1a). We further identified that 14 of 103 Candidate compounds (red square) could significantly inhibit the growth of mycelium at a concentration not higher than 12.5 μm in RPMI 1640 medium (Fig. 1b). We then expanded the types of media that induce mycelial growth (such as YPD medium with 10% FBS, YPD medium with 5 mm GlcNAc, and Spider medium) and used amphotericin B (1.56 μm) as a positive control drug and found that Octenidine (dihydrochloride) still has a significant inhibitory effect on mycelial growth in various mycelial induction media when it is as low as 3.125 μm (Figs. 2a and b).ConclusionOur study demonstrates that Octenidine (dihydrochloride) has a potent hyphal inhibitory activity and is helpful to open the way for the development of new antifungal therapeutics targeting filamentous formation.

S3.4a The repurposing approach identifies pitavastatin (calcium) making fluconazole fungicidal by inhibiting ergosterol synthesis

S3.4 Free oral paper session, September 21, 2022, 4:45 PM - 6:15 PMObjectivesMaking fluconazole (FLC) fungicidal in combination with adjuvants is a promising strategy to avoid the emergence of FLC resistance and eliminate the persistence and recurrence of fungal infections. To address this question, we combined in vitro screening of a library of FDA-approved drugs to identify compounds for making FLC fungicidal.MethodsWe performed a high-throughput screen of an FDA-approved compound library (HY-L022, MCE®), which contains 2372 drugs, to identify potentially novel FLC synergistic lethal adjuvants using broth microdilution and dose-matrix titration assays. The abilities of candidate drugs to turn FLC from fungistatic to fungicidal were further investigated by FLC disk diffusion assays carried out by four tested strains with different FLC tolerance levels (SC5314, SN152, cmp1-aid∆/cmp1-aid∆, and ADH1p-UPC2 strains). We determined the median lethal dose (LD50) of Candidate compounds by the Up-and-Down procedure (UDP) (OECD 425, 2008) via the intraperitoneal route in adult mice and used cyclosporine A and geldanamycin as control drugs to screen FLC synergistic lethal adjuvants with lower toxicity. Finally, we constructed heterozygous deletion mutants for ergosterol synthesis-related genes to identify the mechanism of action of the synergistic lethality of pitavastatin (calcium) (PIT) and FLC (Fig. 1a).ResultsWe found that 200 compounds (≤100 μm) could make FLC (4 μg/ml) fungicidal and further confirmed that 30 compounds turned FLC (4 μg/ml) from fungistatic to fungicidal at a concentration lower than 12.5 μm by broth microdilution assays (Fig. 1b). We further identified that 12/30 compounds (≤3.125 μm) can make FLC fungicidal (≤4 μg/ml) using dose-matrix titration assays. Among these compounds, PIT can make FLC fungicidal at as low as 0.78 μm (Fig. 1c). In the FLC disk diffusion assay, we identified 8 compounds (5 μm) that were superior to or equivalent to the abilities of the control drugs to eliminate the FLC tolerance of four tested strains. It was worth noting that PIT could make FLC fungicidal against all four tested strains (Fig. 1d). The LD50 value of PIT is 103.6 mg/kg and the highest of the tested compounds. Spot assay results showed feeding exogenous 100 μm ergosterol counteracted the antifungal activity of PIT (16 μm) (Fig. 2a), but did not restore the growth defect of Tet-HMG1/hmg1∆ mutant, in which the HMG1 gene expression would be inhibited by tetracycline (Fig. 2b). This paradoxical phenotype suggests that Hmg1 is unlikely to be a target of PIT. We found four heterozygous deletion mutants increased susceptibility to PIT (Fig. 2c) and the growth defect of ERG8/erg8∆ and IDI1/idi1∆ mutants exposed to PIT can be restored by ergosterol (Fig. 2d), suggesting that Erg8 and Idi1 are potential targets of PIT.ConclusionsOur study demonstrates that PIT has a better synergistic lethal effect with FLC by inhibiting ergosterol synthesis and higher safety and suggests that PIT may be repurposed as a promising adjuvant to make FLC fungicidal and enhance the efficacy of FLC in treating invasive fungal infections caused by pathogenic fungi with high FLC tolerance.

S3.5d Identification of fungicidal activity of otilonium bromide by the repurposing approach

S3.5 Environmental exposure - risk for human fungal disease, September 21, 2022, 4:45 PM - 6:15 PM ObjectivesThe development of new antifungal drugs will help to expand the limited antifungal arsenal and curb the emergence of drug resistance. To meet the demand for novel antifungal drugs, we performed a high-throughput screen of an FDA-approved compound library (HY-L022, MCE®) and identified a promising lead antifungal compound, otilonium bromide (OTB).MethodsWe determined antifungal activity of each compound from the library and investigated the antifungal spectrum of OTB using broth microdilution assays (Fig. 1a). We tested the fungicidal effect of OTB by the spot assay and disk diffusion assay. The inhibitory effect of OTB on mycelial growth was identified by observing hyphal growth in hyphal-inducing media containing OTB. The antibiofilm activity of OTB was evaluated by XTT method. We further checked the antifungal activity of OTB in vivo by a murine C. albicans infection model, which was constructed by immunosuppression of mice with cyclophosphamide, inhibiting the intestinal microorganisms by levofloxacin (14 mg/ml), and then gavage with C. albicans cells (1 × 108 cells per mouse). A total of 24 C57 mice were randomly divided into three groups: one group was gavaged with saline, one group with 1 mg/kg fluconazole, and one group with 50 mg/kg OTB. In all 2 h after infection, drugs were given once a day for 4 consecutive days, with 15 days of observation. The death of a mouse was assessed daily and statistically analyzed by Log-rank (Mantel-Cox) test. The toxicity of OTB to human cloned colon adenocarcinoma cells was assessed with MTT method.ResultsWe found that OTB is the most promising lead antifungal molecule among FDA-approved drugs (Fig. 1a). OTB has a broad-spectrum antifungal activity with minimum inhibitory concentration for inhibiting the growth of 50% of strains (MIC50) values ranging from 0.39 to 6.25 μm (Fig. 1b). We found that OTB (≥3.5 μm) has fungicidal effect on C. albicans using spot assay (Fig. 1c). We further found that OTB (25 μg/disk) can form a clear inhibition zone, but not fluconazole (25 μg/disk) (Fig. 1d). Besides, we spotted C. albicans cells from the broth microdilution assays onto YPD solid medium and found that cells treated with OTB (≥1.56 μm) could not recover on YPD solid medium, while cells treated with FLC could (Fig. 1e). It is worth noting that OTB has inhibitory effects on filamentation and biofilm formation at 12.5 μm (Fig. 2a, b), which are key virulence factors of pathogenic fungi. Besides, OTB (50 mg/kg) significantly prolonged the median survival time from 5 days (control group) to 15 days and improved the survival rate from 0% (control group) to 62.5% (P = .0078) (Fig. 2c). Furthermore, we found that OTB exhibited relative low toxicity to mammal cells with IC50 28-57 μm (Fig. 2d), which was much higher than MIC50 against pathogenic fungi.ConclusionOur study highlights that OTB has a broad-spectrum antifungal activity with low MIC50 values and high safety in vitro and potent antifungal efficacy in vivo and will be beneficial to the treatment of devastating invasive fungal infections.

Resveratrol inhibits development of colorectal adenoma via suppression of LEF1; comprehensive analysis with connectivity map.

Although many chemopreventive studies on colorectal tumors have been reported, no effective and safe preventive agent is currently available. We searched for candidate preventive compounds against colorectal tumor comprehensively from United States Food and Drug Administration (FDA)-approved compounds by using connectivity map (CMAP) analysis coupled with in vitro screening with colorectal adenoma (CRA) patient-derived organoids (PDOs). We generated CRA-specific gene signatures based on the DNA microarray analysis of CRA and normal epithelial specimens, applied them to CMAP analysis with 1309 FDA-approved compounds, and identified 121 candidate compounds that should cancel the gene signatures. We narrowed them down to 15 compounds, and evaluated their inhibitory effects on the growth of CRA-PDOs in vitro. We finally identified resveratrol, one of the polyphenolic phytochemicals, as a compound showing the strongest inhibitory effect on the growth of CRA-PDOs compared with normal epithelial PDOs. When resveratrol was administered to ApcMin/+ mice at 15 or 30 mg/kg, the number of polyps (adenomas) was significantly reduced in both groups compared with control mice. Similarly, the number of polyps (adenomas) was significantly reduced in azoxymethane-injected rats treated with 10 or 100 mg/resveratrol compared with control rats. Microarray analysis of adenomas from resveratrol-treated rats revealed the highest change (downregulation) in expression of LEF1, a key molecule in the Wnt signaling pathway. Treatment with resveratrol significantly downregulated the Wnt-target gene (MYC) in CRA-PDOs. Our data demonstrated that resveratrol can be the most effective compound for chemoprevention of colorectal tumors, the efficacy of which is mediated through suppression of LEF1 expression in the Wnt signaling pathway.

Drug library screening identifies histone deacetylase inhibition as a novel therapeutic strategy for choriocarcinoma.

Choriocarcinoma is a rare and aggressive gynecological malignancy. The standard treatment is systemic chemotherapy as choriocarcinoma exhibits high chemosensitivity. However, refractory choriocarcinoma exhibits chemoresistance; thus, the prognosis remains very poor. This study aimed to identify novel therapeutic agents for choriocarcinoma by utilizing a drug repositioning strategy. Three choriocarcinoma cell lines (JAR, JEG-3, and BeWo) and a human extravillous trophoblast cell line (HTR-8/SVneo) were used for the analyses. The growth inhibitory effects of 1,271 FDA-approved compounds were evaluated in vitro screening assays and selected drugs were tested in tumor-bearing mice. Functional analyses of drug effects were performed based on RNA sequencing. Muti-step screening identified vorinostat, camptothecin (S, +), topotecan, proscillaridin A, and digoxin as exhibiting an anti-cancer effect in choriocarcinoma cells. Vorinostat, a histone deacetylase inhibitor, was selected as a promising candidate for validation and the IC50 values for choriocarcinoma cells were approximately 1 μM. RNA sequencing and subsequent pathway analysis revealed that the ferroptosis pathway was likely implicated, and key ferroptosis-related genes (i.e., GPX4, NRF2, and SLC3A2) were downregulated following vorinostat treatment. Furthermore, vorinostat repressed tumor growth and downregulated the expression of GPX4 and NRF2 in JAR cell-bearing mice model. Vorinostat, a clinically approved drug for the treatment of advanced primary cutaneous T-cell lymphoma, showed a remarkable anticancer effect both in vitro and in vivo by regulating the expression of ferroptosis-related genes. Therefore, vorinostat may be an effective therapeutic candidate for patients with choriocarcinoma.

Fludarabine, a Potential DNA-Dependent RNA Polymerase Inhibitor, as a Prospective Drug against Monkeypox Virus: A Computational Approach.

Monkeypox is a zoonotic contagious disease that has recently re-emerged in different countries worldwide. Due to the lack of an effective treatment that eliminates the virus, there is an urgent need to find effective drugs to stop the spread of the multi-country outbreak. The current study aimed to use computational methods to quickly identify potentially effective drugs against the Monkeypox virus (MPXV). Three MPXV proteins were targeted in this study due to their essential role in viral replication (a DNA-Dependent RNA Polymerase subunit (A6R)), a protein involved in cell entry (D8L), and a protein catalyzing the envelopment of intracellular mature virus particles (F13L). We virtually screened a library of 1615 FDA-approved compounds, utilizing different in-silico approaches including computational modeling, molecular docking, molecular dynamic (MD) simulation, and MM-GBSA. The compound Fludarabine was found to have the best docking score (−7.53 kcal/mol) in relation to the MPXV A6R protein. Additionally, Fludarabine showed in-silico activity on the D8L and F13L proteins. During the whole period of the 100 ns MD simulation, the complex of A6R and Fludarabine exhibited the best stability. This stability was reflected in a good score of MM-GBSA, with an average value of −44.62 kcal/mole in a range between −53.26 and −35.49 and a low value of standard deviation (3.76). Furthermore, Fludarabine blocked efficiently the Asn175 residue which has an important role in the attachment of the virus to a host cell. The results of this study recommend more in vitro studies on this compound, as a starting point to develop a novel treatment against MPXV.

P10.21.B Pharmacogenomics profiling of gliomas for precision medicine

Abstract Background Molecular characterization based on genomic, transcriptomic and epigenetic profiling has led to a better delineation of various glioma subtypes and highlighted the individual paths of glioma evolution upon treatment and recurrence. However, due to cellular and molecular diversity of these tumors, the pharmacological treatment of gliomas, in particular of its most malignant subtype Glioblastoma (GBM), remains a major challenge. To address this challenge, we here apply a pharmacogenomics approach, modelling the disease in matched patient-derived preclinical models and profiling the differential drug response among individual patients and glioma subtypes Material and Methods We generated a cohort of 45 Patient-Derived Orthotopic Xenografts (PDOX) from a collection of over 400 glioma patients. We used a multi-parametric approach based on genetic, transcriptomic and longitudinal profiling of patients and their matched xenografts for a comprehensive subgrouping of our glioma cohort. Based on PDOX-derived 3D tumor organoids we carried out a targeted drug screen focused on epigenetic regulators. A high throughput drug screening using an unbiased large chemical library containing a unique collection of FDA approved compounds with high pharmacological diversity is currently ongoing. Results Our glioma cohort with matched PDOX and 3D tumor organoids represents diverse subgroups of glioma patients, including a unique collection of primary and relapsed tumors from the same patient. Our preliminary drug screen analysis on 3D organoids highlights selective susceptibility to certain epigenetic inhibitors in primary disease but not in the same patient’s relapse. Results of matching genomics and functional data will be presented. Conclusion An integrated personalized approach to profile gliomas at multiple genomic and functional levels allows for pharmacogenomic subgrouping of patients for personalized treatment strategies. This analysis will allow to link genotypes to functional phenotypes and hopefully identify therapeutic options for selected glioma sub-populations.

The FDA-approved drug Auranofin has a dual inhibitory effect on SARS-CoV-2 entry and NF-κB signaling

SummaryPatients with severe COVID-19 show an altered immune response that fails to control the viral spread and suffer from exacerbated inflammatory response, which eventually can lead to death. A major challenge is to develop an effective treatment for COVID-19. NF-κB is a major player in innate immunity and inflammatory process. By a high-throughput screening approach, we identified FDA-approved compounds that inhibit the NF-κB pathway and thus dampen inflammation. Among these, we show that Auranofin prevents post-translational modifications of NF-κB effectors and their recruitment into activating complexes in response to SARS-CoV-2 infection or cytokine stimulation. In addition, we demonstrate that Auranofin counteracts several steps of SARS-CoV-2 infection. First, it inhibits a raft-dependent endocytic pathway involved in SARS-CoV-2 entry into host cells; Second, Auranofin alters the ACE2 mobility at the plasma membrane. Overall, Auranofin should prevent SARS-CoV-2 infection and inflammatory damages, offering new opportunities as a repurposable drug candidate to treat COVID-19.

Oncogenic fusion of BCAR4 activates EGFR signaling and is sensitive to dual inhibition of EGFR/HER2.

We previously reported CD63-BCAR4 fusion as a novel oncogene that significantly enhanced cell migration and metastasis in lung cancer. To identify effective inhibitors of metastatic activity induced by BCAR4 fusion, we screened a drug library of 381 FDA-approved compounds. The effect of drugs on cell migration was evaluated by monitoring wound healing. Drugs that decreased the cellular mobility of fusion-overexpressing cells compared with that of control cells were selected as candidates. Library screening revealed that erlotinib, canertinib, and lapatinib demonstrated inhibitory effects on cell migration. Activation of the EGFR signaling pathway was detected after ectopic expression of CD63-BCAR4 in normal bronchial epithelial cells, as observed by the increased phosphorylation of tyrosine residues in the EGFR protein. We also confirmed increased levels of the phosphorylated EGFR protein in resected tumors from mice injected with CD63-BCAR4 overexpressing cells. Tyrosine kinase inhibitors (TKIs) of the EGFR family significantly inhibit the migration of BCAR4 fusion-overexpressing cells and induce apoptosis at high concentrations. Among the EGFR family TKIs, canertinib, a dual EGFR/HER2 inhibitor, showed the best inhibitory effect on the migration and viability of BCAR4 fusion-overexpressing cells. We examined the effect of canertinib in vivo using a mouse xenograft model. Oral administration of canertinib to xenografted mice reduced tumor growth induced by the CD63-BCAR4 fusion gene. In addition, canertinib treatment restored E-cadherin expression and reduced the expression of epithelial–mesenchymal transition regulatory factors such as Slug and Snail. Taken together, these results suggest that EGFR/HER2 inhibitors are potential therapeutic options for BCAR4 fusion-harboring lung cancer patients, even in the absence of EGFR mutations.