The methyltransferase nsp16 is a key enzyme that catalyses coronavirus replication. In this study, we virtually screened 1577 FDA-approved drugs against nsp16 of SARS-CoV-2, SARS-CoV-1, and MERS-CoV to identify compounds potentially serving as pan-coronavirus inhibitors. Microscale thermophoresis (MST) was used to verify the in-silico results obtained by virtual drug screening, followed by molecular docking and molecular dynamics simulation to test the binding affinities between the target and the candidates. Finally, the candidates were tested against a clinical isolate of SARS-CoV-2 in cell culture. The MST binding assay and molecular docking results showed that four of the candidates showed strong binding affinities to nsp16 of one or two coronaviruses. Nilotinib and simeprevir interacted with nsp16 protein of all three coronaviruses, viz., SARS-CoV-2, SARS-CoV-1, and MERS-CoV, suggesting their potential to act as pan-coronavirus inhibitors. The drugs inhibited the virus with IC₅₀ values ranging between 8.34 and 36.1 µM when tested against a clinical isolate of SARS-CoV-2 in cell culture.

Crohn’s disease is an inflammatory bowel disease (IBD) that currently lacks satisfactory treatment options. Therefore, new targets for new drugs are urgently needed to combat this disease. In the present study, we investigated the transcriptomics-based mRNA expression of intestinal biopsies from patients with Crohn’s disease. We compared the mRNA expression profiles of the ileum and colon of patients with those of healthy individuals. A total of 72 genes in the ileum and 33 genes in the colon were differentially regulated. Among these, six genes were overexpressed in both tissues, including IL1B, TCL1A, HCAR3, IGHG1, S100AB, and OSM. We further focused on OSM/oncostatin M. To confirm the responsiveness of intestinal tissues from patients with Crohn’s disease to oncostatin M inhibition, we examined the expression of the oncostatin M using immunohistochemistry in patient biopsies as well as in kindlin-1^−/− and kindlin-2^−/− knockout mice, which exhibit an inflammatory bowel disease (IBD) phenotype, and found strong oncostatin M expression in all samples examined. Next, we conducted a drug-repurposing study using the supercomputer MOGON and bioinformatic methods. A total of 13 candidate compounds out of 1577 FDA-approved drugs were identified by PyRx-based virtual drug screening and AutoDock-based molecular docking. Their lowest binding energies (LBEs) ranged from −10.46 (±0.08) to −8.77 (±0.08) kcal/mol, and their predicted inhibition constants (pK_i) ranged from 21.62 (±2.97) to 373.78 (±36.78) nM. Ecamsule has an interesting stereostructure with two C₂-symmetric enantiomers (1S,4R-1′S,4′R and 1R,4S-1′R,4′S) (1a and 1b) and one meso diastereomer (1S,4R-1′R,4′S) (1c). These three stereoisomers showed strong, albeit differing, binding affinities in molecular docking. As examined by nuclear magnetic resonance and polarimetry, the 1S,4R-1′S,4′R isomer was the stereoisomer present in our commercially available preparations used for microscale thermophoresis. Ecamsule (1a) was chosen for in vitro validation using recombinant oncostatin M and microscale thermophoresis. Considerable dissociation constants were obtained for ecamsule after three repetitions with a K_d value of 11.36 ± 2.83 µM. Subsequently, we evaluated, by qRT-PCR, the efficacy of ecamsule (1a) as a potential drug that could prevent oncostatin M activation by inhibiting downstream inflammatory marker genes (IL6, TNFA, and CXCL11). In conclusion, we have identified oncostatin M as a promising new drug target for Crohn’s disease through transcriptomics and ecamsule as a potential new drug candidate for Crohn’s disease through a drug-repurposing approach both in silico and in vitro.

Background/Objectives: The most abundant flavonoid, quercetin, which is mostly found as glycosides, is widely distributed in plants. Quercetin is rapidly metabolized, having a short half-life in the blood circulation, and forms its conjugates by undergoing ring cleavage of the benzopyranone ring system. Despite its fast clearance in the body, quercetin was demonstrated to have clinically anti-inflammatory, cardioprotective, antidiabetic, and anti-obesity activities. This study aimed to determine whether quercetin itself or its metabolites are responsible for these activities. Methods: We performed molecular docking of 27 metabolites, including quercetin itself, against ten inflammation-related proteins in silico. We then conducted microscale thermophoresis (MST) of selected metabolites towards the NLRP3 inflammasome. Results: Overall, Phase II metabolites yielded better binding energies compared to the metabolites formed by degradation. MST results revealed that isorhamnetin, the 4-O-methylated metabolite of quercetin, gave the best results, with a binding affinity (K_D value) of 16.12 ± 5.16 µM, even better than quercetin itself, which has a binding affinity of 44.84 ± 4.21 µM. Glucuronide metabolites of quercetin (isorhamnetin 3-O-glucuronide, quercetin 7-O-glucuronide, and quercetin 3-O-glucuronide) were found to bind to the inflammasome protein with low binding affinities, whereas small degradation products (hippuric acid and 3,4-dihydroxytoluene) did not bind at all. Conclusions: These results suggest that Phase II metabolites, specifically isorhamnetin, may contribute more significantly to the biological activity of quercetin than the parent compound, however, degradation products appear inactive.

Targeting epigenetics is a new strategy to treat cancer and develop novel epigenetic drugs with anti-tumor activity. DNA methyltransferases transfer the methyl group from S-adenosyl-L-methionine (SAM) to the cytosine residue in a CpG island, leading to the transcription silencing of the gene. Hypermethylation can frequently be observed in several tumor types. Hence, the inhibition of DNMT1 has become a novel approach to cure cancer. In this study, virtual screening and molecular docking were performed for more than 11,000 ligands from the ZINC15 database to discover new hypomethylation agents. Four candidate compounds were further tested for their effects on DNMT1 in silico and in vitro. Compounds 2 and 4 showed the best DNMT1 inhibitory activity, but only compound 4 was able to inhibit the growth of several cancer cell lines. The hypomethylation of the luciferase gene by compound 4 was verified by a CMV- luciferase assay using KG-1 cells. Additionally, compound 4 suppressed cell migration in a dose- and time-dependent manner in the wound healing assay. Moreover, cell cycle analyses demonstrated that compound 4 arrested CCRF-CEM cells and MDA-MB-468 cells in the G0/G1 phase. Also, compound 4 significantly induced early and late apoptosis in a dose-dependent manner. In conclusion, we introduce compound 4 as a novel DNMT1 inhibitor with anticancer activity.

Background/Objectives: Hepatocellular carcinoma (HCC) is challenging to treat with chemotherapy. Immunotherapy has shown moderate responses in inflammatory and immunosuppressive tumor environments. Hepatic cytochrome P450 monooxygenases (CYPs) play a crucial role in xenobiotic and drug metabolism, as well as lipid and steroid metabolism. We aimed to investigate whether CYP expression and various parameters of the innate and adaptive immune system are prognostic factors for the survival of HCC patients. Methods: HCC biopsies (n = 370) from The Cancer Genome Atlas (TCGA) database were analyzed using Kaplan–Meier statistics and the KMPlotter algorithm. Parameters such as immune cell infiltration, DNA mutation rates, and neoantigen load were selected for survival analysis and subjected to hierarchical cluster analysis. The expression of candidate CYP genes in tumors was compared to that in normal liver tissues. Furthermore, tumor infiltration of innate immune cells (basophilic and eosinophilic granulocytes, natural killer cells), adaptive immune cells (CD4+ memory and CD8+ cytotoxic T cells, regulatory T cells, type 1 and type 2 helper T cells), and mesenchymal stem cells was examined. Results: High expression of CYP19A1 and CYP26B1 was associated with shorter survival, whereas high expression of CYP3A5, CYP3A43, CYP7A1, and CYP27A1 was linked to longer survival. Mutation rates combined with CYP expression showed a correlation with five out of six CYP genes, while a high neoantigen load produced less definitive results. A specific cluster exhibiting high CYP expression and immune cell counts or mutation/neoantigen rates was associated with shorter survival, while another cluster was linked to longer survival. Conclusions: CYPs involved in the metabolic regulation of HCC, including CYP3A5, CYP3A43, CYP7A1, CYP19A1, CYP26B1, and CYP27A1, were found to have prognostic value for patient survival. Combined signatures that include CYP expression, mutational rates, and immune cell infiltration into tumors further enhanced the prognostic value for patient survival. This suggests that CYPs may influence the creation of a tumor-specific metabolic microenvironment that impacts immune functions. These combined signatures could be utilized for patient stratification to personalize tumor treatment and develop novel combination therapies aimed at optimizing treatment outcomes, such as combining transarterial chemoembolization (TACE) with immune checkpoint inhibitors.

Background: Telomerase is a ribonucleic multimeric reverse transcriptase complex protecting the chromosomal ends from erosion and thereby from cellular senescence. The prognostic value of the components of this complex and their interrelationships with the immune system are not well understood. Objectives: We aimed to examine 15 telomerase-related genes across 7489 tumor samples from the TCGA database. Methods: The mRNA expression of these genes was analyzed using Kaplan–Meier statistics and hierarchical clustering analyses, alone or in combination with tumor infiltration counts for 11 immune cell types. As an additional analysis, univariable and multivariable Cox regression analyses have been performed. Results: Thirteen of 21 tumor types showed significant associations between gene expression in tumors and survival times of patients. Most gene correlations were found in hepatocellular carcinoma and renal clear cell carcinoma. In hepatocellular carcinoma, a high expression of DKC1, NHP2, GAR1, WRAP53, and ACD was associated with shorter survival. In renal clear cell carcinoma, TERT, DKC1, and PARN correlated with shorter survival, and NAF1, TERF2, POT1, and TINF2 with longer survival. DKC1 was the only gene significantly associated with poor prognosis in both tumor types. The telomerase-related genes correlated with patterns of immune cell infiltration, which influenced the survival of patients. The associations of mutation burden and neoantigen load with survival varied depending on the gene and patient groups. In renal clear cell carcinoma, TERT, DKC1, and PARN showed strong interactions with immune cell infiltration and neoantigen load. Conclusions: The combination of telomerase-related gene expression and immune-cell infiltration was associated with overall survival in hepatocellular carcinoma and renal clear cell carcinoma and warrants further evaluation as prognostic markers.