Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) main protease (Mpro) autocatalytically releases itself out of the viral polyprotein to form a fully active mature dimer in a manner that is not fully understood. Here, we introduce several tools to help elucidate differences between cis (intramolecular) and trans (intermolecular) proteolytic processing and to evaluate inhibition of precursor Mpro. We found that many mutations at the P1 position of the N-terminal autoprocessing site do not block cis autoprocessing but do inhibit trans processing. Notably, substituting the WT glutamine at the P1 position with isoleucine retains Mpro in an unprocessed precursor form that can be purified and further studied. We also developed a cell-based reporter assay suitable for compound library screening and evaluation in HEK293T cells. This assay can detect both overall Mpro inhibition and the fraction of uncleaved precursor form of Mpro through separable fluorescent signals. We observed that inhibitory compounds preferentially block mature Mpro. Bofutrelvir and a novel compound designed in-house showed the lowest selectivity between precursor and mature Mpro, indicating that inhibition of both forms may be possible. Additionally, we observed positive modulation of precursor activity at low concentrations of inhibitors. Our findings help expand understanding of the SARS-CoV-2 viral life cycle and may facilitate development of strategies to target precursor form of Mpro for inhibition or premature activation of Mpro.
- MeSH
- Antiviral Agents * pharmacology chemistry MeSH
- COVID-19 Drug Treatment MeSH
- HEK293 Cells MeSH
- Protease Inhibitors pharmacology chemistry MeSH
- Coronavirus 3C Proteases * metabolism antagonists & inhibitors chemistry genetics MeSH
- Humans MeSH
- Mutation MeSH
- Drug Discovery * methods MeSH
- Proteolysis MeSH
- SARS-CoV-2 * enzymology drug effects metabolism genetics MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
BACKGROUND: Presensitized patients with circulating donor-specific antibodies (DSAs) before transplantation are at risk for antibody-mediated rejection (AMR). Peritransplant desensitization mitigates but does not eliminate the alloimmune response. We examined the possibility that subthreshold AMR activity undetected by histology could be operating in some early biopsies. METHODS: Transcriptome of kidney allograft biopsies performed within the first month in presensitized patients (DSA+) who had received desensitization and did not develop active/probable AMR by histology (R-) was compared with biopsies showing active/probable AMR (R+/DSA+). As negative controls, biopsies without rejection by histology in patients without DSA at transplantation were used (R-/DSA-). RNA sequencing from biopsies selected from the biobank was used in cohort 1 (n = 32) and microarray, including the molecular microscope (Molecular Microscope Diagnostic System [MMDx]) algorithm, in recent cohort 2 (n = 30). RESULTS: The transcriptome of R-/DSA+ was similar to R+/DSA+ as these groups differed in 14 transcripts only. Contrarily, large differences were found between both DSA+ groups and negative controls. Fast gene set enrichment analyses showed upregulation of the immune system in both DSA+ groups (gene ontology terms: adaptive immune response, humoral immune response, antigen receptor-mediated signaling, and B-cell receptor signaling or complement activation) when compared with negative controls. MMDx assessment in cohort 2 classified 50% of R-/DSA+ samples as AMR and found no differences in AMR molecular scores between R+ and R- DSA+ groups. In imlifidase desensitization, MMDx series showed a gradual increase in AMR scores over time. CONCLUSIONS: Presensitized kidney transplant recipients exhibited frequent molecular calls of AMR in biopsy-based transcript diagnostics despite desensitization therapy and negative histology.
- Publication type
- Journal Article MeSH
A double primary colorectal cancer (CRC) in a familial setting signals a high risk of CRC. In order to identify novel CRC susceptibility genes, we whole-exome sequenced germline DNA from nine persons with a double primary CRC and a family history of CRC. The detected variants were processed by bioinformatics filtering and prioritization, including STRING protein-protein interaction and pathway analysis. A total of 150 missense, 19 stop-gain, 22 frameshift and 13 canonical splice site variants fulfilled our filtering criteria. The STRING analysis identified 20 DNA repair/cell cycle proteins as the main cluster, related to genes CHEK2, EXO1, FAAP24, FANCI, MCPH1, POLL, PRC1, RECQL, RECQL5, RRM2, SHCBP1, SMC2, XRCC1, in addition to CDK18, ENDOV, ZW10 and the known mismatch repair genes. Another STRING network included extracellular matrix genes and TGFβ signaling genes. In the nine whole-exome sequenced patients, eight harbored at least two candidate DNA repair/cell cycle/TGFβ signaling gene variants. The number of families is too small to provide evidence for individual variants but, considering the known role of DNA repair/cell cycle genes in CRC, the clustering of multiple deleterious variants in the present families suggests that these, perhaps jointly, contributed to CRC development in these families.
- MeSH
- Adult MeSH
- Genetic Predisposition to Disease * MeSH
- Colorectal Neoplasms * genetics MeSH
- Middle Aged MeSH
- Humans MeSH
- DNA Repair genetics MeSH
- Pedigree MeSH
- Exome Sequencing * methods MeSH
- Aged MeSH
- Germ-Line Mutation * MeSH
- Check Tag
- Adult MeSH
- Middle Aged MeSH
- Humans MeSH
- Male MeSH
- Aged MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
Clinical trials frequently include multiple end points that mature at different times. The initial report, typically based on the primary end point, may be published when key planned co-primary or secondary analyses are not yet available. Clinical Trial Updates provide an opportunity to disseminate additional results from studies, published in JCO or elsewhere, for which the primary end point has already been reported.SEQUOIA (ClinicalTrials.gov identifier: NCT03336333) is a phase III, randomized, open-label trial that compared the oral Bruton tyrosine kinase inhibitor zanubrutinib to bendamustine plus rituximab (BR) in treatment-naïve patients with chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL). The initial prespecified analysis (median follow-up, 26.2 months) and subsequent analysis (43.7 months) found superior progression-free survival (PFS; the primary end point) in patients who received zanubrutinib compared with BR. At a median follow-up of 61.2 months, median PFS was not reached in zanubrutinib-treated patients; median PFS was 44.1 months in BR-treated patients (hazard ratio [HR], 0.29; one-sided P = .0001). Prolonged PFS was seen with zanubrutinib versus BR in patients with mutated immunoglobulin heavy-chain variable region (IGHV) genes (HR, 0.40; one-sided P = .0003) and unmutated IGHV genes (HR, 0.21 [95% CI, 0.14 to 0.33]; one-sided P < .0001). Median overall survival (OS) was not reached in either treatment arm; estimated 60-month OS rates were 85.8% and 85.0% in zanubrutinib- and BR-treated patients, respectively. No new safety signals were detected. Adverse events were as expected with zanubrutinib; rate of atrial fibrillation was 7.1%. At a median follow-up of 61.2 months, the results supported the initial SEQUOIA findings and suggested that zanubrutinib was a favorable treatment option for untreated patients with CLL/SLL.
- MeSH
- Bendamustine Hydrochloride * administration & dosage therapeutic use MeSH
- Leukemia, Lymphocytic, Chronic, B-Cell * drug therapy mortality MeSH
- Progression-Free Survival MeSH
- Adult MeSH
- Middle Aged MeSH
- Humans MeSH
- Follow-Up Studies MeSH
- Piperidines therapeutic use administration & dosage adverse effects MeSH
- Antineoplastic Combined Chemotherapy Protocols * therapeutic use adverse effects MeSH
- Pyrazoles * therapeutic use administration & dosage adverse effects MeSH
- Pyrimidines * therapeutic use administration & dosage adverse effects MeSH
- Rituximab * administration & dosage therapeutic use adverse effects MeSH
- Aged, 80 and over MeSH
- Aged MeSH
- Check Tag
- Adult MeSH
- Middle Aged MeSH
- Humans MeSH
- Male MeSH
- Aged, 80 and over MeSH
- Aged MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
- Clinical Trial, Phase III MeSH
- Multicenter Study MeSH
- Randomized Controlled Trial MeSH
- Comparative Study MeSH
Cancer immunotherapy is increasingly used in clinical practice, but its success rate is reduced by tumor escape from the immune system. This may be due to the genetic instability of tumor cells, which allows them to adapt to the immune response and leads to intratumoral immune heterogeneity. The study investigated spatial immune heterogeneity in the tumor microenvironment and its possible drivers in a mouse model of tumors induced by human papillomaviruses (HPV) following immunotherapy. Gene expression was determined by RNA sequencing and mutations by whole exome sequencing. A comparison of different tumor areas revealed heterogeneity in immune cell infiltration, gene expression, and mutation composition. While the mean numbers of mutations with every impact on gene expression or protein function were comparable in treated and control tumors, mutations with high or moderate impact were increased after immunotherapy. The genes mutated in treated tumors were significantly enriched in genes associated with ECM metabolism, degradation, and interactions, HPV infection and carcinogenesis, and immune processes such as antigen processing and presentation, Toll-like receptor signaling, and cytokine production. Gene expression analysis of DNA damage and repair factors revealed that immunotherapy upregulated Apobec1 and Apobec3 genes and downregulated genes related to homologous recombination and translesion synthesis. In conclusion, this study describes the intratumoral immune heterogeneity, that could lead to tumor immune escape, and suggests the potential mechanisms involved.
- MeSH
- Immunotherapy * methods MeSH
- Papillomavirus Infections immunology virology MeSH
- Humans MeSH
- Disease Models, Animal * MeSH
- Mutation * MeSH
- Mice, Inbred C57BL MeSH
- Mice MeSH
- Tumor Microenvironment * immunology MeSH
- Gene Expression Regulation, Neoplastic MeSH
- Exome Sequencing MeSH
- Tumor Escape genetics MeSH
- Animals MeSH
- Check Tag
- Humans MeSH
- Mice MeSH
- Female MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
Impaired fibroblast growth factor receptor (FGFR) signaling is associated with many human conditions, including growth disorders, degenerative diseases, and cancer. Current FGFR therapeutics are based on chemical inhibitors of FGFR tyrosine kinase activity (TKIs). However, FGFR TKIs are limited in their target specificity as they generally inhibit all FGFRs and other receptor tyrosine kinases. In the search for specific inhibitors of human FGFR1, we identified VZ23, a DNA aptamer that binds to FGFR1b and FGFR1c with a KD of 55 nM and 162 nM, respectively, but not to the other FGFR variants (FGFR2b, FGFR2c, FGFR3b, FGFR3c, FGFR4). In cells, VZ23 inhibited the activation of downstream FGFR1 signaling and FGFR1-mediated regulation of cellular senescence, proliferation, and extracellular matrix homeostasis. Consistent with the specificity toward FGFR1 observed in vitro, VZ23 did not inhibit FGFR2-4 signaling in cells. We show that the VZ23 inhibits FGFR1 signaling in the presence of cognate fibroblast growth factor (FGF) ligands and its inhibitory activity is linked to its capacity to form unusual G-quadruplex structure. Our data suggest that targeting FGFR1 with DNA aptamers could be an effective alternative to TKIs for treating impaired FGFR1 signaling in human craniosynostoses.
- Publication type
- Journal Article MeSH
Bardet-Biedl syndrome (BBS) is a pleiotropic ciliopathy caused by dysfunction of the BBSome, a cargo adaptor essential for export of transmembrane receptors from cilia. Although actin-dependent ectocytosis has been proposed to compensate defective cargo retrieval, its molecular basis remains unclear, especially in relation to BBS pathology. In this study, we investigated how actin polymerization and ectocytosis are regulated within the cilium. Our findings reveal that ciliary CDC42, a RHO-family GTPase triggers in situ actin polymerization, ciliary ectocytosis, and cilia shortening in BBSome-deficient cells. Activation of the Sonic Hedgehog pathway further enhances CDC42 activity specifically in BBSome-deficient cilia. Inhibition of CDC42 in BBSome-deficient cells decreases the frequency and duration of ciliary actin polymerization events, causing buildup of G protein coupled receptor 161 (GPR161) in bulges along the axoneme during Sonic Hedgehog signaling. Overall, our study identifies CDC42 as a key trigger of ciliary ectocytosis. Hyperactive ciliary CDC42 and ectocytosis and the resulting loss of ciliary material might contribute to BBS disease severity.
- MeSH
- Actins * metabolism MeSH
- Bardet-Biedl Syndrome metabolism genetics pathology MeSH
- cdc42 GTP-Binding Protein * metabolism genetics MeSH
- Cilia * metabolism MeSH
- Humans MeSH
- Mice MeSH
- Hedgehog Proteins * metabolism MeSH
- Receptors, G-Protein-Coupled metabolism genetics MeSH
- Signal Transduction * MeSH
- Animals MeSH
- Check Tag
- Humans MeSH
- Mice MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
INTRODUCTION: The E3 ubiquitin ligase Cbl-b is a novel target in immune-oncology, with critical roles in regulating T-cell activation and signaling pathways. By facilitating the ubiquitination and degradation of key signaling proteins, Cbl-b modulates immune responses, maintaining immune homeostasis and preventing unwarranted T-cell proliferation. The therapeutic potential of Cbl-b as a cancer immunotherapy target is underscored by its contribution to an immunosuppressive tumor microenvironment, with efforts currently underway to develop small-molecule inhibitors. AREAS COVERED: We reviewed the small molecules, and antibody-drug conjugates targeting Cbl-b from 2018 to 2024. The patents were gathered through publicly available databases and analyzed with in-house developed cheminformatic workflow, described within the manuscript. EXPERT OPINION: Targeting Cbl-b presents a promising approach in immuno-oncology, offering a novel pathway to potentiate the immune system's ability to combat cancer beyond PDL1/PD1 inhibition. The development and clinical advancement of Cbl-b inhibitors, as evidenced by the ongoing trials, mark a significant step toward harnessing this target for therapeutic benefits. Overall, the strategic inhibition of Cbl-b holds substantial promise for improving cancer immunotherapy outcomes, heralding a new era in the fight against cancer.
- MeSH
- Adaptor Proteins, Signal Transducing MeSH
- Molecular Targeted Therapy * MeSH
- Immunoconjugates pharmacology MeSH
- Immunotherapy * methods MeSH
- Humans MeSH
- Tumor Microenvironment * immunology MeSH
- Neoplasms * immunology drug therapy MeSH
- Patents as Topic * MeSH
- Antineoplastic Agents pharmacology MeSH
- Proto-Oncogene Proteins c-cbl * immunology antagonists & inhibitors MeSH
- Signal Transduction drug effects MeSH
- T-Lymphocytes immunology drug effects MeSH
- Drug Development * MeSH
- Animals MeSH
- Check Tag
- Humans MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Review MeSH
Treatment of gingival fibroblasts with PDL extracellular vesicles results in promotion of Wnt signalling pathway and osteogenic differentiation. PDL secretome shows selective wound healing and matrix remodelling which can have implications for future periodontal regenerative strategies.
- MeSH
- Cell Differentiation MeSH
- Extracellular Vesicles * physiology MeSH
- Fibroblasts physiology MeSH
- Gingiva cytology MeSH
- Wound Healing physiology MeSH
- Humans MeSH
- Osteogenesis physiology MeSH
- Periodontal Ligament * cytology physiology MeSH
- Regeneration * physiology MeSH
- Wnt Signaling Pathway physiology MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
Heavy metals are naturally occurring components of the Earth's crust and persistent environmental pollutants. Human exposure to heavy metals occurs via various pathways, including inhalation of air/dust particles, ingesting contaminated water or soil, or through the food chain. Their bioaccumulation may lead to diverse toxic effects affecting different body tissues and organ systems. The toxicity of heavy metals depends on the properties of the given metal, dose, route, duration of exposure (acute or chronic), and extent of bioaccumulation. The detrimental impacts of heavy metals on human health are largely linked to their capacity to interfere with antioxidant defense mechanisms, primarily through their interaction with intracellular glutathione (GSH) or sulfhydryl groups (R-SH) of antioxidant enzymes such as superoxide dismutase (SOD), catalase, glutathione peroxidase (GPx), glutathione reductase (GR), and other enzyme systems. Although arsenic (As) is believed to bind directly to critical thiols, alternative hydrogen peroxide production processes have also been postulated. Heavy metals are known to interfere with signaling pathways and affect a variety of cellular processes, including cell growth, proliferation, survival, metabolism, and apoptosis. For example, cadmium can affect the BLC-2 family of proteins involved in mitochondrial death via the overexpression of antiapoptotic Bcl-2 and the suppression of proapoptotic (BAX, BAK) mechanisms, thus increasing the resistance of various cells to undergo malignant transformation. Nuclear factor erythroid 2-related factor 2 (Nrf2) is an important regulator of antioxidant enzymes, the level of oxidative stress, and cellular resistance to oxidants and has been shown to act as a double-edged sword in response to arsenic-induced oxidative stress. Another mechanism of significant health threats and heavy metal (e.g., Pb) toxicity involves the substitution of essential metals (e.g., calcium (Ca), copper (Cu), and iron (Fe)) with structurally similar heavy metals (e.g., cadmium (Cd) and lead (Pb)) in the metal-binding sites of proteins. Displaced essential redox metals (copper, iron, manganese) from their natural metal-binding sites can catalyze the decomposition of hydrogen peroxide via the Fenton reaction and generate damaging ROS such as hydroxyl radicals, causing damage to lipids, proteins, and DNA. Conversely, some heavy metals, such as cadmium, can suppress the synthesis of nitric oxide radical (NO·), manifested by altered vasorelaxation and, consequently, blood pressure regulation. Pb-induced oxidative stress has been shown to be indirectly responsible for the depletion of nitric oxide due to its interaction with superoxide radical (O2·-), resulting in the formation of a potent biological oxidant, peroxynitrite (ONOO-). This review comprehensively discusses the mechanisms of heavy metal toxicity and their health effects. Aluminum (Al), cadmium (Cd), arsenic (As), mercury (Hg), lead (Pb), and chromium (Cr) and their roles in the development of gastrointestinal, pulmonary, kidney, reproductive, neurodegenerative (Alzheimer's and Parkinson's diseases), cardiovascular, and cancer (e.g. renal, lung, skin, stomach) diseases are discussed. A short account is devoted to the detoxification of heavy metals by chelation via the use of ethylenediaminetetraacetic acid (EDTA), dimercaprol (BAL), 2,3-dimercaptosuccinic acid (DMSA), 2,3-dimercapto-1-propane sulfonic acid (DMPS), and penicillamine chelators.
- MeSH
- Antioxidants metabolism MeSH
- Bioaccumulation MeSH
- Environmental Pollutants toxicity MeSH
- Humans MeSH
- Oxidative Stress * drug effects MeSH
- Metals, Heavy * toxicity MeSH
- Environmental Exposure adverse effects MeSH
- Animals MeSH
- Check Tag
- Humans MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Review MeSH
