Janus kinase (JAK) inhibitors in the treatment of neoplastic and inflammatory disorders

Discovery and biological evaluation of a novel and highly potent JAK2 inhibitor for the treatment of triple negative breast cancer

Janus kinase 2 (JAK2) is considered an attractive target for the treatment of triple-negative breast cancer (TNBC). Herein, we discovered six JAK2 inhibitors using structure-based virtual screening and molecular docking. Among them, JNN-5 was the best compound. It indicated strong inhibitory effects on JAK2 in the nanomolar range (IC50 = 0.41 ± 0.03 nM), and high selectivity for JAK2 over JAK1 and JAK3 (selectivity index (SI) > 73.17). Moreover, molecular dynamics (MD) simulation exhibited that JNN-5 bound with high stability to JAK2 JH1. Cellular assays revealed that JNN-5 displayed strong antiproliferative activities in the TNBC cell lines (MDA-MB-468, MDA-MB-213, HCC70, MDA-MB-157). JNN-5 significantly reduced the migration of HUVECs with the dose-dependence. JNN-5 had a significant inhibitory effect on multidrug-resistant MDA-MB-231/ADR (IC50 = 0.37 ± 0.02 μM). These data demonstrate that JNN-5 may be a highly effective and selective antitumor compound for the treatment of TNBC.

Cold Storage Disrupts the Proteome and Phosphoproteome Landscape in Rat Kidney Transplants

BACKGROUND

Prolonged cold storage (CS) of kidneys results in poor long-term outcomes after transplantation (Tx). We reported previously that CS of rat kidneys for 18 h before transplant impaired proteasome function, disrupted protein homeostasis, and reduced graft function. The goal of the present study was to identify the renal proteins, including phosphoproteins, that are dysregulated by this CS injury.

METHODS

Isolated donor Lewis rat kidneys were subject to 18 h CS and transplanted into recipient Lewis rats (CS + Tx). Autotransplantation (transplant with 0 h CS) or Sham (right nephrectomy) surgeries served as controls. The proteome of kidney homogenates was analyzed with tandem mass-tag mass spectrometry to identify CS-induced abnormalities in kidney grafts.

RESULTS

CS injury disrupted the renal proteome/phosphoproteome landscape in kidney grafts and dysregulated numerous signaling pathways. We identified 3217 phosphopeptides (with 1398 novel phosphosites) that were significantly dysregulated in a CS-specific manner. In particular, proteins and pathways such as complement system and mitogen-activated protein kinases, including p38MAPK, were upregulated, whereas antioxidant/metabolic pathways, such as glutathione, were suppressed in CS + Tx groups compared with autotransplantation and sham controls.

CONCLUSIONS

This study provides deeper insight into the disruption of the renal proteome/phosphoproteome caused by CS injury and provides a novel set of pathways and molecules, including p38MAPK, that can be investigated to delineate their specific role in renal transplant outcomes, ultimately improving outcomes for patients with end-stage kidney disease.

Dibromo-Edaravone Induces Anti-Erythroleukemia Effects via the JAK2-STAT3 Signaling Pathway

Acute erythroid leukemia (AEL) is a rare and aggressive hematological malignancy managed with chemotherapy, targeted therapies, and stem cell transplantation. However, these treatments often suffer from limitations such as refractoriness, high toxicity, recurrence, and drug resistance, underscoring the urgent need for novel therapeutic approaches. Dibromo-edaravone (D-EDA) is a synthetic derivative of edaravone (EDA) with unreported anti-leukemic properties. In this study, D-EDA demonstrated potent cytotoxicity against HEL cells with an IC50 value of 8.17 ± 0.43 μM using an MTT assay. Morphological analysis via inverted microscopy revealed reductions in cell number and signs of cellular crumpling and fragmentation. Flow cytometry analysis, Hoechst 33258 staining, Giemsa staining, a JC-1 assay, and a reactive oxygen species (ROS) assay showed that D-EDA induced apoptosis in HEL cells. Furthermore, D-EDA induced S-phase cell cycle arrest. Western blot analysis showed significant upregulation of key apoptosis-related proteins, including cleaved caspase-9, cleaved caspase-3, and cleaved poly ADP-ribose polymerase (PARP), alongside a reduction in Bcl-2 expression. Additionally, oncogenic markers such as c-Myc, CyclinA2, and CDK2 were downregulated, while the cell cycle inhibitor p21 was upregulated. Mechanistic studies involving molecular docking, a cellular thermal shift assay (CETSA), the caspase inhibitor Z-VAD-FMK, JAK2 inhibitor Ruxolitinib, and STAT3 inhibitor Stattic revealed that D-EDA activates the caspase cascade and inhibits the JAK2-STAT3 signaling pathway in HEL cells. In vivo, D-EDA improved spleen structure, increased the hemolysis ratio, and extended survival in a mouse model of acute erythroleukemia. In conclusion, D-EDA induces apoptosis via the caspase cascade and JAK2-STAT3 signaling pathway, demonstrating significant anti-leukemia effects in vitro and in vivo. Thus, D-EDA may be developed as a potential therapeutic agent for acute erythroleukemia.

Properties of FDA-approved small molecule protein kinase inhibitors: A 2025 update

Because of the deregulation of protein kinase action in many inflammatory diseases and cancer, the protein kinase family has become one of the most significant drug targets in the 21st century. There are 85 FDA-approved protein kinase antagonists that target about two dozen different enzymes and four of these drugs were approved in 2024 and a fifth was approved in 2025. Of these drugs, five target dual specificity protein kinases (MEK1/2), fourteen inhibit protein-serine/threonine protein kinases, twenty-one block nonreceptor protein-tyrosine kinases, and 45 target receptor protein-tyrosine kinases. The data indicate that 75 of these drugs are prescribed for the treatment of neoplasms. Seven drugs (abrocitinib, baricitinib, deucravacitinib, deuruxolitinib, ritlecitinib, tofacitinib, upadacitinib) are prescribed for the management of inflammatory diseases (atopic dermatitis, rheumatoid arthritis, psoriasis, alopecia areata, and ulcerative colitis). Of the 85 FDA-approved agents, about two dozen are used in the treatment of multiple diseases. The following four drugs received FDA approval in 2024 - deuruxolitinib (alopecia areata), ensartinib and lazertinib (non-small cell lung cancer), and tovorafenib (pediatric glioma) while mirdametinib was approved in 2025 for the treatment of type I neurofibromatosis (von Recklinghausen disease). Apart from netarsudil, temsirolimus, and trilaciclib, the approved protein kinase blockers are orally bioavailable. This article summarizes the physicochemical properties of all 85 FDA-approved small molecule protein kinase inhibitors including the molecular weight, number of hydrogen bond donors/acceptors, ligand efficiency, lipophilic efficiency, polar surface area, and solubility. A total of 39 of the 85 FDA-approved drugs have a least one Lipinski rule of 5 violation.

Nature-Inspired Anticancer Agents: The Synergy of Phytochemicals and Synthetic Analogs (2019-2024)

Cancer remains one of the most formidable global health challenges, marked by uncontrolled cell growth and division. Despite medical advancements, traditional treatments often fall short due to issues of specificity, resistance, and toxicity, compounded by the complex pathophysiology of the disease. In this context, natural products, particularly phytochemicals, have emerged as promising anticancer agents. Compounds such as vinca alkaloids, curcuminoids, flavonoids, terpenoids, polyphenols, and others have demonstrated potent anticancer properties by targeting key molecular pathways, including protein kinases, aromatase, EGFR, TNF-α, HER-2, and caspases. This review explores recent advancements in phytochemical research from 2019 to 2024 and includes natural product-inspired synthetic derivatives with enhanced therapeutic potential. A comprehensive literature survey was conducted using databases such as PubMed, Scopus, Web of Science, and Google Scholar. Keywords used included "phytochemicals," "natural products," "cancer," "anticancer agents," "kinase inhibitors," "EGFR," "HER2," "aromatase," and "synthetic analogs." Articles were selected based on relevance, recency, and impact in the field. By providing mechanistic insights and highlighting novel compounds with clinical relevance, this work underscores the critical role of phytochemicals and their derivatives in addressing current therapeutic limitations and shaping future cancer treatments.

Discovery of a Highly Potent and Selective Tyrosine Kinase 2 (TYK2) Degrader with In Vivo Therapeutic Efficacy in a Murine Psoriasis Model

Tyrosine kinase 2 (TYK2), a critical scaffolding kinase required for type I interferon, IL-12 and IL-23 cytokine signaling, represents a compelling therapeutic target for various autoimmune diseases. However, existing TYK2 inhibitors only modulate its kinase activity. Here, we report the development of a first series of CRBN-recruiting TYK2 PROTACs based on an allosteric TYK2 inhibitor. Optimization of the potency and metabolic stability identified 15t as an exceptionally potent and selective TYK2 degrader with a DC50 value of 0.42 nM and a Dmax value of 95%, which potently and selectively blocked TYK2-dependent signaling. Importantly, 15t was active in vivo and significantly suppressed TYK2-mediated pathology in a murine psoriasis model without apparent toxicity. Collectively, our study provides a potentially valuable chemical knockdown probe for subtype-selective TYK2 degradation and further understanding TYK2 scaffolding biology, demonstrating the therapeutic potential of TYK2 PROTACs in immuno-inflammatory diseases such as psoriasis.

STAT3 Signaling Pathway in Health and Disease

Signal transducer and activator of transcription 3 (STAT3) is a critical transcription factor involved in multiple physiological and pathological processes. While STAT3 plays an essential role in homeostasis, its persistent activation has been implicated in the pathogenesis of various diseases, particularly cancer, bone-related diseases, autoimmune disorders, inflammatory diseases, cardiovascular diseases, and neurodegenerative conditions. The interleukin-6/Janus kinase (JAK)/STAT3 signaling axis is central to STAT3 activation, influencing tumor microenvironment remodeling, angiogenesis, immune evasion, and therapy resistance. Despite extensive research, the precise mechanisms underlying dysregulated STAT3 signaling in disease progression remain incompletely understood, and no United States Food and Drug Administration (USFDA)-approved direct STAT3 inhibitors currently exist. This review provides a comprehensive evaluation of STAT3's role in health and disease, emphasizing its involvement in cancer stem cell maintenance, metastasis, inflammation, and drug resistance. We systematically discuss therapeutic strategies, including JAK inhibitors (tofacitinib, ruxolitinib), Src Homology 2 domain inhibitors (S3I-201, STATTIC), antisense oligonucleotides (AZD9150), and nanomedicine-based drug delivery systems, which enhance specificity and bioavailability while reducing toxicity. By integrating molecular mechanisms, disease pathology, and emerging therapeutic interventions, this review fills a critical knowledge gap in STAT3-targeted therapy. Our insights into STAT3 signaling crosstalk, epigenetic regulation, and resistance mechanisms offer a foundation for developing next-generation STAT3 inhibitors with greater clinical efficacy and translational potential.

Dual inhibition of TYK2 and PD-L1 boosts immune response in triple negative breast cancer

Recent studies have shown that Janus Kinase inhibitors can enhance the tumor therapeutic effect of immune checkpoint inhibitors. However, it remains to be studied whether TYK2 selective inhibitors can enhance the therapeutic effect of small molecule PD-L1 inhibitors in triple-negative breast cancer (TNBC). We verified the efficacy of the combination of the selective TYK2 inhibitor Deucravacitinib and the small molecule inhibitor of PD-L1, INCB086550, in two TNBC animal models: a syngeneic mouse model (4T1 with humanized PD-L1) and a peripheral blood mononuclear cell (PBMC)-humanized model (MDA-MB-231). Following that, we explored the regulation of immune cell activity in tumors by the combined treatment using flow cytometry. Finally, we validated the expression of genes related to the regulated immune cells through reverse transcription-PCR. Both animal models demonstrated that the addition of a TYK2 inhibitor to a PD-L1 inhibitor significantly enhanced the antitumor capabilities of mice with good safety profiles. The combined therapy significantly elevated the counts of T, B, and natural killer cells while concurrently diminishing myeloid-derived suppressor cells in the syngeneic model. Similarly, in the PBMC-humanized model, this therapy markedly augmented progenitor-like and proliferative precursor-like CD8 T cells, while effectively diminishing exhausted and terminally differentiated CD8 T cell populations. This enhanced antitumor effect is associated with the modulation of antitumor immune-related gene expression by the combined therapy. The combination of TYK2 inhibitors and immune checkpoint inhibitors is a potentially effective strategy for treating TNBC.

Chromosome-level genome assembly of Iodes seguinii and its metabonomic implications for rheumatoid arthritis treatment

Iodes seguinii is a woody vine known for its potential therapeutic applications in treating rheumatoid arthritis (RA) due to its rich bioactive components. Here, we achieved the first chromosome-level assembly of the nuclear genome of I. seguinii using PacBio HiFi and chromatin conformation capture (Hi-C) sequencing data. The initial assembly with PacBio data produced contigs with an N50 length of 9.71 Mb, and Hi-C data anchored these contigs into 13 chromosomes, achieving a total length of 273.58 Mb, closely matching the estimated genome size. Quality assessments, including BUSCO, long terminal repeat assembly index, transcriptome mapping rates, and sequencing coverage, confirmed the high quality, completeness, and continuity of the assembly, identifying 115.28 Mb of repetitive sequences, 1062 RNA genes, and 25,270 protein-coding genes. Additionally, we assembled and annotated the 150,599 bp chloroplast genome using Illumina sequencing data, containing 121 genes including key DNA barcodes, with maturase K (matK) proving effective for species identification. Phylogenetic analysis positioned I. seguinii at the base of the Lamiales clade, identifying significant gene family expansions and contractions, particularly related to secondary metabolite synthesis and DNA damage repair. Metabolite analysis identified 84 active components in I. seguinii, including the discovery of luteolin, with 119 targets predicted for RA treatment, including core targets like AKT1, toll-like receptor 4 (TLR4), epidermal growth factor receptor (EGFR), tumor necrosis factor (TNF), TP53, NFKB1, janus kinase 2 (JAK2), BCL2, mitogen-activated protein kinase 1 (MAPK1), and spleen-associated tyrosine kinase (SYK). Key active components such as flavonoids and polyphenols with anti-inflammatory activities were highlighted. The discovery of luteolin, in particular, underscores its potential therapeutic role. These findings provide a valuable genomic resource and a scientific basis for the development and application of I. seguinii, addressing the genomic gap in the genus Iodes and the order Icacinales and underscoring the need for further research in genomics, transcriptomics, and metabolomics to fully explore its potential.

Luteolin inhibits diffuse large B-cell lymphoma cell growth through the JAK2/STAT3 signaling pathway

Luteolin, a flavonoid present in botanical drugs, plants, and dietary sources, has demonstrated anticancer properties against various tumors, yet its role in diffuse large B-cell lymphoma (DLBCL) remains unclear. This study aimed to uncover the molecular mechanism of luteolin in DLBCL treatment using a combination of in vitro and in vivo experiments and computational analysis. Human DLBCL cell lines U2932 and OCI-LY10 were utilized to assess luteolin's impact on cell growth, apoptosis, cell cycle progression, and the modulation of JAK2/STAT3 pathway proteins. In vivo, a U2932 tumor-bearing nude mice model was employed to evaluate luteolin's antitumor efficacy and its effects on JAK2/STAT3 pathway protein expression. Additionally, molecular dynamics simulations were conducted to explore the interaction between luteolin and JAK2. The findings revealed that luteolin significantly suppressed cell proliferation, induced apoptosis, and arrested the cell cycle at the G2/M phase in both cell lines. In the mouse model, luteolin effectively inhibited tumor growth and downregulated the expression of phosphorylated JAK2 and STAT3 without altering the total protein levels of JAK2 and STAT3. Computational analysis indicated stable binding of luteolin to JAK2. Collectively, these results suggest that luteolin's anti-DLBCL activity may be mediated through the regulation of the JAK2/STAT3 signaling pathway, positioning it as a potential therapeutic agent for DLBCL.

Tyrosine kinase 2 inhibitors: Synthesis and applications in the treatment of autoimmune diseases

Janus kinase (JAK), a class of non-receptor tyrosine kinases, are essential in modulating the cytokine signaling cascade of cytokines associated with immune responses. Despite their potential in the treatment of autoimmune diseases, JAK inhibitors are associated with safety concerns, regarding cytokine suppression and significant side effects. Tyrosine kinase 2 (TYK2), a prominent member of the JAK family, is central to the signaling of interleukins (ILs) and interferons (IFNs), such as IL-12, IL-23 and IFNs. Targeted TYK2 inhibitors that specifically target the Janus Homology 1 (JH1) and pseudokinase (JH2) domains show enhanced specificity. JH1 acts as an ATP-competitive inhibitor, while JH2 acts as an allosteric regulator, contributing to reduced systemic side effects and improved therapeutic outcomes in clinical settings. This review summarizes the recent advances on the synthetic strategies of TYK2 inhibitors and their applications in the treatment of autoimmune diseases.

Small Molecules, Big Results: How JAK Inhibitors Have Transformed the Treatment of Patients with IBD

Small molecule Janus kinase (JAK) inhibitors have revolutionized the management of ulcerative colitis (UC) and Crohn's disease (CD) through their low immunogenicity, safety, and consistent pharmacologic response that are superior to existing therapeutic options. In this perspective, we highlight existing evidence supporting the use of currently approved JAK inhibitors (upadacitinib, tofacitinib, and filgotinib) for UC or CD, additionally emphasizing the evidence for their use in related autoimmune conditions such as rheumatoid arthritis and spondyloarthropathies. Our perspective concludes with a review of the existing comparative effectiveness literature, which positions JAK inhibitors, particularly upadacitinib, favorably compared with other biologic therapies. This perspective is paired with a companion publication highlighting the origins and development of JAK inhibitors and a more in-depth review of their pathophysiologic mechanisms.

Mechanisms and therapeutic prospect of the JAK-STAT signaling pathway in liver cancer

Liver cancer (LC) poses a significant global health challenge due to its high incidence and poor prognosis. Current systemic treatment options, such as surgery, chemotherapy, radiofrequency ablation, and immunotherapy, have shown limited effectiveness for advanced LC patients. Moreover, owing to the heterogeneous nature of LC, it is crucial to uncover more in-depth pathogenic mechanisms and develop effective treatments to address the limitations of the existing therapeutic modalities. Increasing evidence has revealed the crucial role of the Janus kinase (JAK)-signal transducer and activator of transcription (STAT) pathway in the pathogenesis of LC. The specific mechanisms driving the JAK-STAT pathway activation in LC, participate in a variety of malignant biological processes, including cell differentiation, evasion, anti-apoptosis, immune escape, and treatment resistance. Both preclinical and clinical investigations on the JAK-STAT pathway inhibitors have exhibited potential in LC treatment, thereby opening up avenues for the development of more targeted therapeutic strategies for LC. In this study, we provide an overview of the JAK-STAT pathway, delving into the composition, activation, and dynamic interplay within the pathway. Additionally, we focus on the molecular mechanisms driving the aberrant activation of the JAK-STAT pathway in LC. Furthermore, we summarize the latest advancements in targeting the JAK-STAT pathway for LC treatment. The insights presented in this review aim to underscore the necessity of research into the JAK-STAT signaling pathway as a promising avenue for LC therapy.

Research progress on the pathogenesis of psoriasis and its small molecule inhibitors

Psoriasis is a prevalent chronic systemic immune disease characterized by T-cellmediated hyperproliferation of keratinized cells. Among its various manifestations, plaque-type psoriasis is the most common. Treatment options for psoriasis encompass topical medications, biological therapies, phototherapy techniques, and others. However, traditional treatments are associated with numerous side effects. In contrast, targeted therapy has garnered increasing attention due to its high selectivity, strong safety profile, and favorable therapeutic outcomes. Patients with psoriasis lesions exhibit elevated levels of proinflammatory cytokines compared with the general population. These proinflammatory cytokines have been implicated in mediating psoriasis pathogenesis by inducing keratinocyte proliferation through multiple signaling pathways within the body. This study will delve into the Janus kinase-signal transducers and activators of transcription, phosphatidylinositol 3 kinase (PI3K)-protein kinase B (PKB, also known as AKT), and nuclear factor Kappa-light-chain-enhancer of activated B cells signaling pathways to elucidate their roles in mediating psoriasis pathogenesis. In addition, we will summarize potential targets relevant to the treatment of psoriasis and discuss the design and activity assessment of their inhibitors. It also provides new insights for further in-depth study of psoriasis and development of novel molecularly targeted inhibitors.

Kinase-Bench: Comprehensive Benchmarking Tools and Guidance for Achieving Selectivity in Kinase Drug Discovery

Developing selective kinase inhibitors remains a formidable challenge in drug discovery because of the highly conserved structural information on adenosine triphosphate (ATP) binding sites across the kinase family. Tailoring docking protocols to identify promising kinase inhibitor candidates for optimization has long been a substantial obstacle to drug discovery. Therefore, we introduced "Kinase-Bench," a pioneering benchmark suite designed for an advanced virtual screen, to improve the selectivity and efficacy of kinase inhibitors. Our comprehensive data set includes 6875 selective ligands and 422,799 decoys for 75 kinases, using extensive bioactivity and structural data from the ChEMBL database and decoys generated by the Directory of Useful Decoys-Enhanced version. Our benchmarking sets and retrospective case studies were designed to provide useful guidance in discovering selective kinase inhibitors. We employed a Glide High-Throughput Virtual Screen and Standard Precision complemented by three scoring functions and customized protein-ligand interaction filters that target specific kinase residue interactions. These innovations were successfully implemented in our virtual screen efforts targeting JAK1 inhibitors, achieving selectivity against its family member, TYK2. Consequently, we identified novel potential hits: Compound 2 (JAK1 IC50: 980.5 nM, TYK2 IC50: 4.5 μM) and the approved pan-AKT inhibitor Capivasertib (JAK1 IC50: 275.9 nM, TYK2 IC50: 10.9 μM). Using the Kinase-Bench protocol, both compounds demonstrated substantial JAK1 selectivity, making them strong candidates for further investigation. Our pharmaceutical results underscore the utility of tailored virtual screen protocols in identifying selective kinase inhibitors with substantial implications for rational drug design. Kinase-Bench offers a robust toolset for selective kinase drug discovery with the potential to effectively guide future therapeutic strategies effectively.

Repigmentation in non-segmental vitiligo using the Janus kinase inhibitor upadacitinib, a retrospective case series

Vitiligo is the most frequently diagnosed depigmentation disease, affecting nearly 0.5-2% of individuals worldwide. This disorder is characterized by melanocyte loss, which results in skin and hair depigmentation. Psychological problems are common in patients, especially in those with the involvement of the face and hands. Several studies have recently focused on the use of JAK inhibitors for vitiligo treatment. However, studies on the selective JAK1 inhibitor upadacitinib for vitiligo treatment are limited. This study aimed to assess the efficacy and safety of upadacitinib in the treatment of vitiligo. This retrospective case series included five patients diagnosed with non-segmental vitiligo who were treated with upadacitinib for 4 months or longer. Disease severity was assessed using the Vitiligo Area Scoring Index (VASI). Five patients took 15 mg of upadacitinib orally for 4 consecutive months, and all achieved repigmentation. The plasma collected from the peripheral blood of the four patients showed that the CXCL9 level dropped after upadacitinib treatment. However, the CXCL10 level did not change significantly using enzyme-linked immunosorbent assay (ELISA). Flow cytometry revealed that the ratio of CD4 + CD3+/CD8 + CD3 + T cells in the blood samples tended to decrease through the treatment. And the Th1-like Tregs (CD4 + Foxp3 + IFN-γ + Tregs) were also downregulated in the peripheral blood. In conclusion, the JAK1 inhibitor upadacitinib was found to be effective and safe for treating non-segmental vitiligo.

Medicinal chemistry perspective of JAK inhibitors: synthesis, biological profile, selectivity, and structure activity relationship

JAK-STAT signalling pathway was discovered more than quarter century ago. The JAK-STAT pathway protein is considered as one of the crucial hubs for cytokine secretion which mediates activation of different inflammatory, cellular responses and hence involved in different etiological factors. The various etiological factors involved are haematopoiesis, immune fitness, tissue repair, inflammation, apoptosis, and adipogenesis. The presence of the active mutation V617K plays a significant role in the progression of the JAK-STAT pathway-related disease. Consequently, targeting the JAK-STAT pathway could be a promising therapeutic approach for addressing a range of causative factors. In this current review, we provided a comprehensive discussion for the in-detail study of anatomy and physiology of the JAK-STAT pathway which contributes structural domain rearrangement, activation, and negative regulation associated with the downstream signaling pathway, relationship between different cytokines and diseases. This review also discussed the recent development of clinical trial entities. Additionally, this review also provides updates on FDA-approved drugs. In the current investigation, we have classified recently developed small molecule inhibitors of JAK-STAT pathway according to different chemical classes and we emphasized their synthetic routes, biological evaluation, selectivity, and structure-activity relationship.

Deciphering the therapeutic potential of Myeloid-Specific JAK2 inhibition in acute respiratory distress syndrome

Acute respiratory distress syndrome (ARDS) is a life-threatening condition characterized by severe inflammation and pulmonary dysfunction. Despite advancements in critical care, effective pharmacological interventions for ARDS remain elusive. While Janus kinase 2 (JAK2) inhibitors have emerged as an innovative treatment for numerous autoinflammatory diseases, their therapeutic potential in ARDS remains unexplored. In this study, we investigated the contribution of JAK2 and its underlying mechanisms in ARDS utilizing myeloid-specific JAK2 knockout murine models alongside a pharmacological JAK2 inhibitor. Notably, myeloid-specific JAK2 knockout led to a notable attenuation of ARDS induced by intratracheal administration of LPS, accompanied by reduced levels of neutrophils and inflammatory cytokines in bronchoalveolar lavage fluid (BALF) and lung tissue. Intriguingly, the ameliorative effects were abolished upon the depletion of monocyte-derived alveolar macrophages (Mo-AMs) rather than tissue-resident alveolar macrophages (TR-AMs). JAK2 deficiency markedly reversed LPS-induced activation of STAT5 in macrophages. Remarkably, pharmacological JAK2 inhibition using baricitinib failed to substantially alleviate neutrophils infiltration, implying that specific inhibition of JAK2 in Mo-AMs is imperative for ARDS amelioration. Collectively, our data suggest that JAK2 may mitigate ARDS progression through the JAK2 pathway in Mo-AMs, underscoring JAK2 in alveolar macrophages, particularly Mo-AMs, as a promising therapeutic target for ARDS treatment.

Clinical pharmacokinetic characteristics of Jaktinib in subjects with hepatic impairment in a phase I trial

Jaktinib is a novel Janus kinase (JAK) inhibitor, and a phase I clinical trial of single-dose Jaktinib was conducted in a population of subjects with hepatic impairment to assess the safety, tolerability, and pharmacokinetic characteristics of Jaktinib. The patients were administered orally with 100 mg Jaktinib on day 1 in all the mild hepatic impairment group (mild group, n = 8), moderate hepatic impairment group (moderate group, n = 8) and normal hepatic function group (normal group, n = 8), and the blood samples were collected for later analysis. The mild to moderate hepatic impairment affected the metabolism of Jaktinib, which may lead to accumulation of original Jaktinib. The pharmacokinetic characteristics of the metabolites (ZG0244 and ZG0245) of Jaktinib were also analyzed. The exposure of Jaktinib is approximately 2-fold in patients with mild and moderate hepatic impairment than normal hepatic function. No serious adverse events occurred. In summary, a dosage reduction is recommended for patients with mild or moderate hepatic impairment. Further investigations for the dose adjustment in mild/moderate hepatic impairment will be considered. Trial registration number: NCT04993404.

Two cases of eosinophilic pustular folliculitis successfully treated with abrocitinib

Eosinophilic pustular folliculitis (EPF) is a rare, non-infectious, inflammatory disease characterized by an eosinophil-dominated infiltrate within and around pilosebaceous units. Sometimes, EPF manifests with eruptions in follicle-free areas, although it is not common, and treatment may be difficult. In this case study we report two patients with refractory EPF who presented with eruptions of both classic follicle areas and follicle-free areas. These two patients were successfully treated with abrocitinib after treatment failure with several traditional therapies, such as indomethacin, steroids, and cyclosporin. One patient achieved complete remission at week 4 and the other at week 1, with no reported adverse effects. Therefore, we believe that abrocitinib may be a viable and safe therapeutic option for refractory EPF.

Chinese medicine in the treatment of chronic hepatitis B: The mechanisms of signal pathway regulation

Chronic hepatitis B (CHB) is a chronic inflammatory disease of the liver caused by infection with the hepatitis B virus (HBV), which in later stages can lead to the development of end-stage liver diseases such as cirrhosis and hepatocellular carcinoma in severe cases, jeopardizing long-term quality of life, with a poor prognosis, and placing a serious financial burden on many families around the world. The pathogenesis of the disease is complex and closely related to the immune function of the body, which has not yet been fully elucidated. The development of chronic hepatitis B is closely related to the involvement of various signaling pathways, such as JAK/STAT, PI3K/Akt, Toll-like receptor, NF-κB and MAPK signaling pathways. A large number of studies have shown that Chinese medicine has obvious advantages in anti-hepatitis B virus, and it can effectively treat the disease by modulating relevant signaling pathways, strengthening immune resistance and defense, and inhibiting inflammatory responses, and certain research progress has been made, but there is still a lack of a comprehensive review on the modulation of relevant signaling pathways in Chinese medicine for the treatment of CHB. Therefore, this article systematically combed and elaborated the relevant literature on the modulation of relevant signaling pathways by traditional Chinese medicine in recent years, with a view to providing new ideas for the treatment of CHB and further drug development.

Efficacy and Potential Mechanisms of Naringin in Atopic Dermatitis

Atopic dermatitis (AD) is one of the most prevalent chronic inflammatory skin diseases. Topical treatments are recommended for all patients regardless of severity, making it essential to develop an effective topical AD treatment with minimal side effects; We investigated the efficacy of topical application of naringin in AD and explored the possible mechanisms using an AD mouse model induced by 1-chloro-2,4-dinitrobenzene (DNCB). Clinical, histological, and immunological changes related to AD and Janus kinase (JAK)-signal transducer and activator of transcription (STAT) signaling proteins in the skin tissues were measured as outcomes; Naringin treatment resulted in a significant improvement in dermatitis severity score and reduced epidermal thickness and mast cell count in the skin (p < 0.05). Naringin also demonstrated the ability to inhibit DNCB-induced changes in interleukin (IL) 4, chemokine (C-C motif) ligand (CCL) 17, CCL22, IL1β, interferon-gamma (IFN-γ), and tumor necrosis factor-alpha (TNF-α) levels by quantitative real-time polymerase chain reaction (qRT-PCR) and IL13 by enzyme-linked immunosorbent assay (ELISA) (p < 0.05). Western blot results exhibited the decreased JAK1, JAK2, STAT1, STAT3, phospho-STAT3, and STAT6 expression in the naringin-treated groups (p < 0.05); The findings of this study suggest that topical naringin may effectively improve the symptoms of AD and could be used as a therapeutic agent for AD.

From pre-clinical efficacy to promising clinical trials that delay Type 1 diabetes

Recent advancements in immunology and islet biology have unveiled remarkable prospects for the postponement of Type 1 diabetes (T1D) through the strategic modulation of the immune system. In this Perspective, we discuss the pharmaceutical strides achieved, traversing from pre-clinical validation to the execution of impactful clinical trials. We begin with the initial investigations involving cyclosporine and glucocorticoids in rodent models, such as the non-obese diabetic (NOD) mouse, which guided early clinical trials. We then discuss the pre-clinical studies using suitable mouse models that eventually led to contemporary clinical trials targeting immune cell functionality and cytokine signaling pathways. Collectively, these discoveries promote the exciting paradigm of immune system modulation to mitigate autoimmunity, which continues to broaden. Notably, the use of baricitinib, a potent JAK1/2 inhibitor, and teplizumab, an anti-CD3 monoclonal antibody, represent discrete methodologies converging upon a singular outcome: the preservation of islet beta-cell functionality. The latter interventional strategies build on the original idea that tempering specific facets of the immune system will generate therapeutic benefit. Enthusiasm from these discoveries stems from efficacy with reduced side effects when compared with past approaches. The success of therapeutic intervention(s) in pre-clinical studies, combined with knowledge about stages of progression to clinical T1D, have ultimately encouraged the design of more successful clinical trials targeting highly specific populations at risk. Collectively, these findings instill a profound sense of optimism, suggesting that the prevention and even reversal of T1D may soon be within reach.

Systematic review of Janus kinases inhibitors for rheumatoid arthritis: methodology, reporting, and quality of evidence evaluation

Objective

To evaluate the methodological, reporting and evidence quality of systematic reviews or meta-analyses of Janus kinases (JAK) inhibitors for the treatment of rheumatoid arthritis (RA).

Methods

Our study systematically retrieved reviews from various databases, spanning from inception to June 2024. Two evaluators independently assessed the methodological, reporting, and evidence quality of each review using the AMSTAR-2 and PRIAMA2020 tools. The evidence quality was evaluated according to GRADE criteria. Six aspects were evaluated: publication year, study type, homogeneity, risk of publication bias, AMSTAR-2 methodology, and PRIAMA2020 reporting quality. Excel 2016 facilitated conversion of scores into radar plots.

Results

Following stringent selection criteria, a total of 18 relevant studies were identified. The AMSTAR-2 scores ranged from 4 to 13 points, with five studies rated as low quality and the remaining 13 as critically low quality. All studies encompassed populations, interventions, controls, and outcome measures, demonstrating commendable integrity. However, there is room for improvement in study protocol development and registration, comprehensive search strategies, inclusion and exclusion criteria, conflict of interest disclosure, and discussion of heterogeneity. PRIAMA2020 assessments ranged from 14.5 to 21 points, with two studies scoring below 15 points due to increased bias risk from data transformation and sensitivity analysis. Notably, all reviews (100%) adhered to PRIAMA2020 guidelines for certain items but none met all criteria. GRADE evaluation included 446 outcome measures, with 158 of moderate, 156 of low, and 132 of very low quality, indicating JAK inhibitors is effective in improving RA. According to radar chart, the average rank score was 13.13. One study achieved a balanced score across all dimensions, while 11 exceeded the average, five showed significant differences in PRIAMA2020 scores, and four in AMSTAR two scores.

Conclusion

Despite summarizing the efficacy and safety of JAK inhibitors in treating RA, the included studies exhibited poor methodological and reporting quality, along with low-quality evidence overall. Therefore, caution is warranted among decision-makers regarding the use of JAK inhibitors in RA treatment. Urgent requirements include high-quality, multicenter studies investigating JAK inhibitors for RA.

Systematic Review registration

https://www.crd.york.ac.uk/PROSPERO, identifier 413415.

Tetrastigma hemsleyanum polysaccharide ameliorated ulcerative colitis by remodeling intestinal mucosal barrier function via regulating the SOCS1/JAK2/STAT3 pathway

Ulcerative colitis (UC) is characterized by a chronic and protracted course and often leads to a poor prognosis. Patients with this condition often experience postoperative complications, further complicating the management of their condition. Tetrastigma hemsleyanum polysaccharide (THP) has demonstrated considerable potential as a treatment for inflammatory bowel disease. However, its underlying mechanism in the treatment of UC remains unclear. This study systematically and comprehensively investigated the effects of THP on dextran sulfate-induced UC mice and illustrated its specific mechanism of action. The colon and spleen in UC mice were restored after THP treatment. The levels of key markers, such as secretory immunoglobulin A, β-defensin, and mucin-2 were increased, collagen deposition and epithelial cell apoptosis were decreased. Notably, THP administration led to increased levels of Ki67 and tight junction proteins in colon tissue and reduced colon tissue permeability. THP contributed to the restored balance of intestinal flora. Furthermore, THP downregulated the expressions of the proinflammatory cytokines interleukin (IL)-6, tumor necrosis factor (TNF)-α, and IL-17 and promoted those of the regulatory factors forkhead box protein P3. It also exerted anti-inflammatory effects by promoting suppressor of cytokine signaling (SOCS1) expression and inhibiting the Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) signaling pathway. Our results demonstrated that THP had an efficacy comparable to that of JAK inhibitor in treating UC. In addition, THP might play a role in UC therapy through modulation of the SOCS1/JAK2/STAT3 signaling pathway and remodeling of the intestinal mucosal barrier.

Enhancement of vincristine sensitivity in retinoblastoma through Janus kinase inhibition by ruxolitinib

Chemotherapy remains the main approach conserving vision during the treatment of retinoblastoma, the most prevalent eye cancer in children. Unfortunately, the development of chemoresistance stands as the primary reason for treatment failure. Within this study, we showed that prolonged exposure to vincristine led to heightened expression of JAK1 and JAK2 in retinoblastoma cells, while the other members of the JAK family exhibited no such changes. Employing a genetic intervention, we demonstrated the efficacy of depleting either JAK1 or JAK2 in countering vincristine-resistant retinoblastoma cells. In addition, the dual depletion of both JAK1 and JAK2 produced a more potent inhibitory outcome compared to the depletion of either gene alone. We further demonstrated that ruxolitinib, a small molecular inhibitor of JAK1/2, effectively reduced viability and colony formation in vincristine-resistant retinoblastoma cells. It also acts synergistically with vincristine in retinoblastoma cells regardless of inherent cellular and genetic heterogeneity. The effectiveness of ruxolitinib as standalone treatment against chemoresistant retinoblastoma, as well as its combination with vincristine, was validated in multiple retinoblastoma mouse models. Importantly, mice exhibited favorable tolerance to ruxolitinib administration. We confirmed that the underlying mechanism of ruxolitinib's action in chemoresistant retinoblastoma cells is the inhibition of Janus kinase/signal transducer and activator of transcription (JAK/STAT) signaling. Our study reveals that the underlying mechanism driving ruxolitinib's impact on chemoresistant retinoblastoma cells is the inhibition of JAK/STAT signaling. This study reveals the contribution of JAK1/2 to the development of chemoresistance in retinoblastoma and underscores the effectiveness of targeting JAK1/2 as a strategy to sensitize retinoblastoma to chemotherapy.

Strategic pathway analysis for dual management of epilepsy and comorbid depression: a systems biology perspective

Depression is a common psychiatric comorbidity among patients with epilepsy (PWE), affecting more than a third of PWE. Management of depression may improve quality of life of epileptic patients. Unfortunately, available antidepressants worsen epilepsy by reducing the seizure threshold. This situation demands search of new safer target for combined directorate of epilepsy and comorbid depression. A system biology approach may be useful to find novel pathways/markers for the cure of both epilepsy and associated depression via analyzing available genomic and proteomic information. Hence, the system biology approach using curated 64 seed genes involved in temporal lobe epilepsy and mental depression was applied. The interplay of 600 potential proteins was revealed by the Disease Module Detection (DIAMOnD) Algorithm for the treatment of both epilepsy and comorbid depression using these seed genes. The gene enrichment analysis of seed and diamond genes through DAVID suggested 95 pathways. Selected pathways were refined based on their syn or anti role in epilepsy and depression. In conclusion, total 8 pathways and 27 DIAMOnD genes/proteins were finally deduced as potential new targets for modulation of selected pathways to manage epilepsy and comorbid depression.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40203-024-00208-1.

Deciphering the molecular mechanism of NLRP3 in BPA-mediated toxicity: Implications for targeted therapies

Bisphenol-A (BPA), a pervasive industrial chemical used in polymer synthesis, is found in numerous consumer products including food packaging, medical devices, and resins. Detectable in a majority of the global population, BPA exposure occurs via ingestion, inhalation, and dermal routes. Extensive research has demonstrated the adverse health effects of BPA, particularly its disruption of immune and endocrine systems, along with genotoxic potential. This review focuses on the complex relationship between BPA exposure and the NOD-like receptor protein 3 (NLRP3) inflammasome, a multiprotein complex central to inflammatory disease processes. We examine how BPA induces oxidative stress through the generation of intracellular free radicals, subsequently activating NLRP3 signaling. The mechanistic details of this process are explored, including the involvement of signaling cascades such as PI3K/AKT, JAK/STAT, AMPK/mTOR, and ERK/MAPK, which are implicated in NLRP3 inflammasome activation. A key focus of this review is the wide-ranging organ toxicities associated with BPA exposure, including hepatic, renal, gastrointestinal, and cardiovascular dysfunction. We investigate the immunopathogenesis and molecular pathways driving these injuries, highlighting the interplay among BPA, oxidative stress, and the NLRP3 inflammasome. Finally, this review explores the emerging concept of targeting NLRP3 as a potential therapeutic strategy to mitigate the organ toxicities stemming from BPA exposure. This work integrates current knowledge, emphasizes complex molecular mechanisms, and promotes further research into NLRP3-targeted interventions.

Study on tissue distribution, metabolite profiling, and excretion of [14C]-labeled flonoltinib maleate in rats

Flonoltinib Maleate (FM) is a dual-target inhibitor that selectively suppresses Janus kinase 2/FMS-like tyrosine kinase 3 (JAK2/FLT3), which is currently in phase I/IIa clinical trial in China for the treatment of myeloproliferative neoplasms (MPNs). In this research, we used [14C]-labeled FM (14C-FM) to investigate the distribution, metabolism, and excretion of FM in rats using High-Performance Liquid Chromatography coupled with High-Resolution Mass Spectrometry/Radioactivity Monitoring (HPLC-HRMS/RAM) and liquid scintillation counter. The results revealed that FM displayed widespread distribution in rats. Furthermore, FM demonstrated rapid clearance without any observed risk of organ toxicity attributed to accumulation. Profiling of FM metabolites in rat plasma, feces, urine, and bile identified a total of 17 distinct metabolites, comprising 7 phase I metabolites and 10 phase II metabolites. The major metabolic reactions involved oxygenation, dealkylation, methylation, sulfation, glucuronidation and glutathione conjugation. Based on these findings, a putative metabolic pathway of FM in rats was proposed. The overall recovery rate in the excretion experiment ranged from 93.04 % to 94.74 %. The results indicated that FM undergoes extensive hepatic metabolism in SD rats, with the majority being excreted through bile as metabolites and ultimately eliminated via feces. A minor fraction of FM (<10 %) was excreted through renal excretion in the form of urine. Integration of the current results with previous pharmacokinetic investigations of FM in rats and dogs enables a comprehensive elucidation of the in vivo ADME processes and characteristics of FM, thereby establishing a solid foundation for subsequent clinical investigations of FM.

The long coiled-coil protein NECC2 regulates oxLDL-induced endothelial oxidative damage and exacerbates atherosclerosis development in apolipoprotein E -/- mice

Oxidized low density lipoprotein (oxLDL)-induced endothelial oxidative damage promotes the development of atherosclerosis. Caveolae play an essential role in maintaining the survival and function of vascular endothelial cell (VEC). It is reported that the long coiled-coil protein NECC2 is localized in caveolae and is associated with neural cell differentiation and adipocyte formation, but its role in VECs needs to be clarified. Our results showed NECC2 expression increased in the endothelium of plaque-loaded aortas and oxLDL-treated HUVECs. Down-regulation of NECC2 by NECC2 siRNA or compound YF-307 significantly inhibited oxLDL-induced VEC apoptosis and the adhesion factors expression. Remarkably, inhibition of NECC2 expression in the endothelium of apoE-/- mice by adeno-associated virus (AAV)-carrying NECC2 shRNA or compound YF-307 alleviated endothelium injury and restricted atherosclerosis development. The immunoprecipitation results confirmed that NECC2 interacted with Tyk2 and caveolin-1(Cav-1) in VECs, and NECC2 further promoted the phosphorylation of Cav-1 at Tyr14 b y activating Tyk2 phosphorylation. On the other hand, inhibiting NECC2 levels suppressed oxLDL-induced phosphorylation of Cav-1, uptake of oxLDL by VECs, accumulation of intracellular reactive oxygen species and activation of NF-κB. Our findings suggest that NECC2 may contribute to oxLDL-induced VEC injury and atherosclerosis via modulating Cav-1 phosphorylation through Tyk2. This work provides a new concept and drug target for treating atherosclerosis.

Ruxolitinib induces apoptosis and pyroptosis of anaplastic thyroid cancer via the transcriptional inhibition of DRP1-mediated mitochondrial fission

Anaplastic thyroid carcinoma (ATC) has a 100% disease-specific mortality rate. The JAK1/2-STAT3 pathway presents a promising target for treating hematologic and solid tumors. However, it is unknown whether the JAK1/2-STAT3 pathway is activated in ATC, and the anti-cancer effects and the mechanism of action of its inhibitor, ruxolitinib (Ruxo, a clinical JAK1/2 inhibitor), remain elusive. Our data indicated that the JAK1/2-STAT3 signaling pathway is significantly upregulated in ATC tumor tissues than in normal thyroid and papillary thyroid cancer tissues. Apoptosis and GSDME-pyroptosis were observed in ATC cells following the in vitro and in vivo administration of Ruxo. Mechanistically, Ruxo suppresses the phosphorylation of STAT3, resulting in the repression of DRP1 transactivation and causing mitochondrial fission deficiency. This deficiency is essential for activating caspase 9/3-dependent apoptosis and GSDME-mediated pyroptosis within ATC cells. In conclusion, our findings indicate DRP1 is directly regulated and transactivated by STAT3; this exhibits a novel and crucial aspect of JAK1/2-STAT3 on the regulation of mitochondrial dynamics. In ATC, the transcriptional inhibition of DRP1 by Ruxo hampered mitochondrial division and triggered apoptosis and GSDME-pyroptosis through caspase 9/3-dependent mechanisms. These results provide compelling evidence for the potential therapeutic effectiveness of Ruxo in treating ATC.

Integrative Multiomics Profiling Unveils the Protective Function of Ulinastatin against Dextran Sulfate Sodium-Induced Colitis

Ulcerative colitis is an inflammatory bowel disease with multiple pathogeneses. Here, we aimed to study the therapeutic role of ulinastatin (UTI), an anti-inflammatory bioagent, and its associated mechanisms in treating colitis. Dextran sulfate sodium was administrated to induce colitis in mice, and a subgroup of colitis mice was treated with UTI. The gut barrier defect and inflammatory manifestations of colitis were determined via histological and molecular experiments. In addition, transcriptomics, metagenomics, and metabolomics were employed to explore the possible mechanisms underlying the effects of UTI. We found that UTI significantly alleviated the inflammatory manifestations and intestinal barrier damage in the mice with colitis. Transcriptome sequencing revealed a correlation between the UTI treatment and JAK-STAT signaling pathway. UTI up-regulated the expression of SOCS1, which subsequently inhibited the phosphorylation of JAK2 and STAT3, thus limiting the action of inflammatory mediators. In addition, 16S rRNA sequencing illustrated that UTI maintained a more stable intestinal flora, protecting the gut from dysbiosis in colitis. Moreover, metabolomics analysis demonstrated that UTI indeed facilitated the production of some bile acids and short-chain fatty acids, which supported intestinal homeostasis. Our data provide evidence that UTI is effective in treating colitis and support the potential use of UTI treatment for patients with ulcerative colitis.

Properties of FDA-approved small molecule protein kinase inhibitors: A 2024 update

Owing to the dysregulation of protein kinase activity in many diseases including cancer, this enzyme family has become one of the most important drug targets in the 21st century. There are 80 FDA-approved therapeutic agents that target about two dozen different protein kinases and seven of these drugs were approved in 2023. Of the approved drugs, thirteen target protein-serine/threonine protein kinases, four are directed against dual specificity protein kinases (MEK1/2), twenty block nonreceptor protein-tyrosine kinases, and 43 inhibit receptor protein-tyrosine kinases. The data indicate that 69 of these drugs are prescribed for the treatment of neoplasms. Six drugs (abrocitinib, baricitinib, deucravacitinib, ritlecitinib, tofacitinib, upadacitinib) are used for the treatment of inflammatory diseases (atopic dermatitis, rheumatoid arthritis, psoriasis, alopecia areata, and ulcerative colitis). Of the 80 approved drugs, nearly two dozen are used in the treatment of multiple diseases. The following seven drugs received FDA approval in 2023: capivasertib (HER2-positive breast cancer), fruquintinib (metastatic colorectal cancer), momelotinib (myelofibrosis), pirtobrutinib (mantle cell lymphoma, chronic lymphocytic leukemia, small lymphocytic lymphoma), quizartinib (Flt3-mutant acute myelogenous leukemia), repotrectinib (ROS1-positive lung cancer), and ritlecitinib (alopecia areata). All of the FDA-approved drugs are orally effective with the exception of netarsudil, temsirolimus, and trilaciclib. This review summarizes the physicochemical properties of all 80 FDA-approved small molecule protein kinase inhibitors including the molecular weight, number of hydrogen bond donors/acceptors, polar surface area, potency, solubility, lipophilic efficiency, and ligand efficiency.

An Antiherpesviral Host-Directed Strategy Based on CDK7 Covalently Binding Drugs: Target-Selective, Picomolar-Dose, Cross-Virus Reactivity

The repertoire of currently available antiviral drugs spans therapeutic applications against a number of important human pathogens distributed worldwide. These include cases of the pandemic severe acute respiratory coronavirus type 2 (SARS-CoV-2 or COVID-19), human immunodeficiency virus type 1 (HIV-1 or AIDS), and the pregnancy- and posttransplant-relevant human cytomegalovirus (HCMV). In almost all cases, approved therapies are based on direct-acting antivirals (DAAs), but their benefit, particularly in long-term applications, is often limited by the induction of viral drug resistance or side effects. These issues might be addressed by the additional use of host-directed antivirals (HDAs). As a strong input from long-term experiences with cancer therapies, host protein kinases may serve as HDA targets of mechanistically new antiviral drugs. The study demonstrates such a novel antiviral strategy by targeting the major virus-supportive host kinase CDK7. Importantly, this strategy focuses on highly selective, 3D structure-derived CDK7 inhibitors carrying a warhead moiety that mediates covalent target binding. In summary, the main experimental findings of this study are as follows: (1) the in vitro verification of CDK7 inhibition and selectivity that confirms the warhead covalent-binding principle (by CDK-specific kinase assays), (2) the highly pronounced antiviral efficacies of the hit compounds (in cultured cell-based infection models) with half-maximal effective concentrations that reach down to picomolar levels, (3) a particularly strong potency of compounds against strains and reporter-expressing recombinants of HCMV (using infection assays in primary human fibroblasts), (4) additional activity against further herpesviruses such as animal CMVs and VZV, (5) unique mechanistic properties that include an immediate block of HCMV replication directed early (determined by Western blot detection of viral marker proteins), (6) a substantial drug synergism in combination with MBV (measured by a Loewe additivity fixed-dose assay), and (7) a strong sensitivity of clinically relevant HCMV mutants carrying MBV or ganciclovir resistance markers. Combined, the data highlight the huge developmental potential of this host-directed antiviral targeting concept utilizing covalently binding CDK7 inhibitors.

Cost in the United States of FDA-approved small molecule protein kinase inhibitors used in the treatment of neoplastic and non-neoplastic diseases

Because genetic alterations including mutations, overexpression, translocations, and dysregulation of protein kinases are involved in the pathogenesis of many illnesses, this enzyme family is the target of many drug discovery programs worldwide. The FDA has approved 80 small molecule protein kinase inhibitors with 77 drugs orally bioavailable. The data indicate that 69 of these medicinals are approved for the management of neoplasms including solid tumors such as breast and lung cancer as well as non-solid tumors such as leukemia. Moreover, the remaining 11 drugs target non-neoplastic diseases including psoriasis, rheumatoid arthritis, and ulcerative colitis. The cost of drugs was obtained from www.pharmacychecker.com using the FDA label to determine the dosage and number of tablets required per day. This methodology excludes any private or governmental insurance coverage, which would cover the entire cost or more likely a fraction of the stated price. The average monthly cost for the treatment of neoplastic diseases was $17,900 with a price of $44,000 for futibatinib (used to treat cholangiocarcinomas with FGFR2 fusions) and minimum of $5100 for binimetinib (melanoma). The average monthly cost for the treatment of non-neoplastic diseases was $6800 with a maximum of $17,000 for belumosudil (graft vs. host disease) and a minimum of $200 for netarsudil eye drops (glaucoma). There is a negative correlation of the cost of the drugs and the incidence of the targeted disease. Many of these agents are or were designated as orphan drugs meaning that there are fewer than 200,000 potential patients in the United States.

IL-6/JAK2-dependent G6PD phosphorylation promotes nucleotide synthesis and supports tumor growth

OBJECTIVE

Tumor cells hijack inflammatory mechanisms to promote their own growth. IL-6 is one of the major cytokines, and is frequently upregulated in tumors. The pentose phosphate pathway (PPP) generates the indispensable building blocks to produce various nucleotides. Here we aimed to determine whether and how PPP is timely tuned in response to IL-6 to support tumor growth.

METHODS

Protein expression was examined by immunoblot. Protein interaction was examined by immunoprecipitation. Tumor cell proliferation in in vitro culture was examined by BrdU assay and colony formation assay. Tumor cell proliferation in mouse xenograft model was examined by Ki-67 staining.

RESULTS

Here we show that the metabolic flux of PPP and enzymatic activity of glucose-6-phosphate dehydrogenase (G6PD) is rapidly induced under IL-6 treatment, without obvious changes in G6PD expression level. Mechanistically, Janus kinase 2 (JAK2) phosphorylates G6PD Y437 under IL-6 treatment, which accentuates G6PD enzymatic activity by promoting G6PD binding with its substrate G6P. Further, JAK2-dependent G6PD Y437 phosphorylation is required for IL-6-induced nucleotide biosynthesis and tumor cell proliferation, and is associated with the progression of oral squamous cell carcinoma.

CONCLUSIONS

Our findings report a new mechanism implicated in the crosstalk between tumor cells and inflammatory microenvironment, by which JAK2-dependent activation of G6PD governs nucleotide synthesis to support tumor cell proliferation, thereby highlighting its value as a potential anti-tumor target.

Recent advances in the structural biology of tyrosine kinases

The past few years have seen exciting discoveries in the area of tyrosine kinase structural biology including the first high resolution models of full-length receptor tyrosine kinases and new mechanistic insights into the structural mechanisms of receptor tyrosine kinase activation. Despite being a mature area of research, the application of new technologies continues to advance our understanding. In this article we highlight a selection of recent studies that illustrate the current areas of research interest, focussing in particular on the exciting progress made possible by cryo-electron-microscopy. These new discoveries may herald a wave of new design ideas for therapeutics acting through novel mechanisms.

Intracellular spatiotemporal metabolism in connection to target engagement

The metabolism in eukaryotic cells is a highly ordered system involving various cellular compartments, which fluctuates based on physiological rhythms. Organelles, as the smallest independent sub-cell unit, are important contributors to cell metabolism and drug metabolism, collectively designated intracellular metabolism. However, disruption of intracellular spatiotemporal metabolism can lead to disease development and progression, as well as drug treatment interference. In this review, we systematically discuss spatiotemporal metabolism in cells and cell subpopulations. In particular, we focused on metabolism compartmentalization and physiological rhythms, including the variation and regulation of metabolic enzymes, metabolic pathways, and metabolites. Additionally, the intricate relationship among intracellular spatiotemporal metabolism, metabolism-related diseases, and drug therapy/toxicity has been discussed. Finally, approaches and strategies for intracellular spatiotemporal metabolism analysis and potential target identification are introduced, along with examples of potential new drug design based on this.

Progress on the Pharmacological Targeting of Janus Pseudokinases

The Janus kinases (JAKs) are key components of the JAK-STAT signaling pathway and are involved in myriad physiological processes. Though they are the molecular targets of many FDA-approved drugs, these drugs manifest adverse effects due in part to their inhibition of the requisite JAK kinase activity. However, the JAKs uniquely possess an integrated pseudokinase domain (JH2) that regulates the adjacent kinase domain (JH1). The therapeutic targeting of JH2 domains has been less thoroughly explored and may present an avenue to modulate the JAKs without the adverse effects associated with targeting the adjacent JH1 domain. The potential of this strategy was recently demonstrated with the FDA approval of the TYK2 JH2 ligand deucravacitinib for treating plaque psoriasis. In this light, the structure and targetability of the JAK pseudokinases are discussed, in conjunction with the state of development of ligands that bind to these domains.

Network pharmacological analysis on the mechanism of Coix seed decoction for osteoarthritis of the knee

Based on network pharmacology methods, we explored the mechanism of the classic Chinese medicine formula Coix seed decoction (CSD) in treating knee osteoarthritis (KOA). We searched each single drug in the CSD in the traditional Chinese medicine systematic pharmacology database in turn to obtain information on the active ingredients and target proteins of the CSD, and obtain the name of the genes corresponding to the target proteins through the UniProt database. We collected KOA-related genes from DisGeNET, GeneCards, comparative toxicogenomics database, and MalaCards database. The Venny online tool identified potential therapeutic targets by intersecting CSD and KOA target genes, while gene ontology and Kyoto encyclopedia of genes and genomes analysis was performed using the Oebiotech Cloud Platform. A protein-protein interaction network was established using the String database; a "CSD-active ingredient-target gene-KOA" network plot was constructed using Cytoscape 3.9.1 software and screened for key targets and hub targets. Finally, molecular docking was performed for hub genes with high Degree values. A total of 227 effective target genes for CSD and 8816 KOA-related target genes were obtained, as well as 191 cross-target genes for CSD and KOA. We screened 37 key gene targets and identified the top 10 hub target genes in descending order of Degree value using protein-protein interaction and Cytoscape 3.9.1 software (TNF, IL-6, MMP-9, IL-1β, AKT-1, VEGFα, STAT-3, PTGS-2, IL-4, TP53). Gene ontology analysis showed that the biological process of CSD treatment of KOA mainly involves cytokine-mediated signaling pathway, negative regulation of apoptotic process, cellular response to hypoxia, cellular response to cadmium ion, response to estradiol, and extrinsic apoptotic signaling pathway in absence of ligand. Kyoto encyclopedia of genes and genomes analysis revealed major signaling pathways including Cellular senescence, TNF signaling pathway, and PI3K-Akt signaling pathway. The molecular docking results show that the core components bind well to the core targets. In conclusion, CSD may exert therapeutic effects on KOA by inhibiting pathological processes such as inflammatory response, apoptosis, cellular senescence, and oxidative stress.

Small molecule protein kinase inhibitors approved by regulatory agencies outside of the United States

Owing to genetic alterations and overexpression, the dysregulation of protein kinases plays a significant role in the pathogenesis of many autoimmune and neoplastic disorders and protein kinase antagonists have become an important drug target. Although the efficacy of imatinib in the treatment of chronic myelogenous leukemia in the United States in 2001 was the main driver of protein kinase inhibitor drug discovery, this was preceded by the approval of fasudil (a ROCK antagonist) in Japan in 1995 for the treatment of cerebral vasospasm. There are 21 small molecule protein kinase inhibitors that are approved in China, Japan, Europe, and South Korea that are not approved in the United Sates and 75 FDA-approved inhibitors in the United States. Of the 21 agents, eleven target receptor protein-tyrosine kinases, eight inhibit nonreceptor protein-tyrosine kinases, and two block protein-serine/threonine kinases. All 21 drugs are orally bioavailable or topically effective. Of the non-FDA approved drugs, sixteen are prescribed for the treatment of neoplastic diseases, three are directed toward inflammatory disorders, one is used for glaucoma, and fasudil is used in the management of vasospasm. The leading targets of kinase inhibitors approved by both international regulatory agencies and by the FDA are members of the EGFR family, the VEGFR family, and the JAK family. One-third of the 21 internationally approved drugs are not compliant with Lipinski's rule of five for orally bioavailable drugs. The rule of five relies on four parameters including molecular weight, number of hydrogen bond donors and acceptors, and the Log of the partition coefficient.

Investigating the risk of deep vein thrombosis with JAK inhibitors: a disproportionality analysis using FDA Adverse Event Reporting System Database (FAERS)

BACKGROUND

Janus kinase (JAK) inhibitors are immune-modulating medications used to treat conditions including rheumatoid arthritis, COVID-19, ulcerative colitis, atopic dermatitis, myelofibrosis, and polycythemia Vera. However, these medications have been associated with higher incidence of deep vein thrombosis. The objective of this study was to investigate potential safety signals for DVT associated with JAK inhibitors using disproportionality analysis from the FDA Adverse Event Reporting System (FAERS) database.

RESEARCH DESIGN AND METHODS

The authors retrospectively investigated case/non-case analysis using Openvigil 2.1-MedDRA-v24 (2004Q1 to 2022Q4). The preferred term used was 'deep vein thrombosis,' and the drugs included were baricitinib, tofacitinib, and upadacitinib. Reporting odds ratio, proportional reporting ratio, and information component were used to detect signals.

RESULTS

Overall 114,005 AE reports related to JAK inhibitors were identified, of which 647 reports (baricitinib - 169, tofacitinib - 425, and upadacitinib - 53) associated with DVT were obtained from FAERS. On analysis, baricitinib and tofacitinib had greater signal strength for age group of 65-100 years and all three had the highest signal strength for male gender.

CONCLUSIONS

Our study identified signals for DVT with baricitinib, tofacitinib, and upadacitinib. Further research using well-designed epidemiological data is needed to validate these results.

Ruxolitinib Treatment During Myelofibrosis Leads to Cutaneous Mycobacterium marinum Infection: A Case Report

Mycobacterium marinum is an atypical bacterium, and skin infections caused by it are relatively rare, usually occurring in workers engaged in seafood processing and housewives who clean and prepare fish for consumption. The infection often occurs after the skin is punctured by fish scales, spines, etc. The JAK/STAT signaling pathway is closely related to the human immune response to infections. Therefore, JAK inhibitors may induce and exacerbate various infections in clinical practice. This article reports a case of mycobacterium marinum skin infection in the left upper limb of a female patient with chronic idiopathic myelofibrosis during treatment with ruxolitinib. The patient denied being punctured or scratched by fish scales or spines. Clinical manifestations included multiple infiltrative erythemas and subcutaneous nodules in the thumb and forearm. Histopathological examination showed infiltration of mixed acute and chronic inflammatory cells in the subcutaneous tissue. The diagnosis was ultimately confirmed by NGS sequencing. The patient was cured after taking moxifloxacin and clarithromycin for 10 months. Infection is a common adverse reaction of JAK inhibitors, but no literature has reported on mycobacterium marinum skin infections occurring during JAK inhibitor treatment, which is relatively rare. As the clinical application of JAK inhibitors becomes more widespread, the skin infections they cause may present in various forms and require the attention of clinicians.

Small molecule inhibitors of RORγt for Th17 regulation in inflammatory and autoimmune diseases

As a ligand-dependent transcription factor, retinoid-associated orphan receptor γt (RORγt) that controls T helper (Th) 17 cell differentiation and interleukin (IL)-17 expression plays a critical role in the progression of several inflammatory and autoimmune conditions. An emerging novel approach to the therapy of these diseases thus involves controlling the transcriptional capacity of RORγt to decrease Th17 cell development and IL-17 production. Several RORγt inhibitors including both antagonists and inverse agonists have been discovered to regulate the transcriptional activity of RORγt by binding to orthosteric- or allosteric-binding sites in the ligand-binding domain. Some of small-molecule inhibitors have entered clinical evaluations. Therefore, in current review, the role of RORγt in Th17 regulation and Th17-related inflammatory and autoimmune diseases was highlighted. Notably, the recently developed RORγt inhibitors were summarized, with an emphasis on their optimization from lead compounds, efficacy, toxicity, mechanisms of action, and clinical trials. The limitations of current development in this area were also discussed to facilitate future research.

Evolving cognition of the JAK-STAT signaling pathway: autoimmune disorders and cancer

The Janus kinase (JAK) signal transducer and activator of transcription (JAK-STAT) pathway is an evolutionarily conserved mechanism of transmembrane signal transduction that enables cells to communicate with the exterior environment. Various cytokines, interferons, growth factors, and other specific molecules activate JAK-STAT signaling to drive a series of physiological and pathological processes, including proliferation, metabolism, immune response, inflammation, and malignancy. Dysregulated JAK-STAT signaling and related genetic mutations are strongly associated with immune activation and cancer progression. Insights into the structures and functions of the JAK-STAT pathway have led to the development and approval of diverse drugs for the clinical treatment of diseases. Currently, drugs have been developed to mainly target the JAK-STAT pathway and are commonly divided into three subtypes: cytokine or receptor antibodies, JAK inhibitors, and STAT inhibitors. And novel agents also continue to be developed and tested in preclinical and clinical studies. The effectiveness and safety of each kind of drug also warrant further scientific trials before put into being clinical applications. Here, we review the current understanding of the fundamental composition and function of the JAK-STAT signaling pathway. We also discuss advancements in the understanding of JAK-STAT-related pathogenic mechanisms; targeted JAK-STAT therapies for various diseases, especially immune disorders, and cancers; newly developed JAK inhibitors; and current challenges and directions in the field.

JAK1 Pseudokinase V666G Mutant Dominantly Impairs JAK3 Phosphorylation and IL-2 Signaling

Overactive Janus kinases (JAKs) are known to drive leukemia, making them well-suited targets for treatment. We sought to identify new JAK-activating mutations and instead found a JAK1-inactivating pseudokinase mutation, V666G. In contrast to other pseudokinase mutations that canonically lead to an active kinase, the JAK1 V666G mutation led to under-activation seen by reduced phosphorylation. To understand the functional role of JAK1 V666G in modifying kinase activity we investigated its influence on other JAK kinases and within the Interleukin-2 pathway. JAK1 V666G not only inhibited its own activity, but its presence could inhibit other JAK kinases. These findings provide new insights into the potential of JAK1 pseudokinase to modulate its own activity, as well as of other JAK kinases. Thus, the features of the JAK1 V666 region in modifying JAK kinases can be exploited to allosterically inhibit overactive JAKs.

Deucravacitinib is an allosteric TYK2 protein kinase inhibitor FDA-approved for the treatment of psoriasis

Psoriasis is a heterogeneous, inflammatory, autoimmune skin disease that affects up to 2% of the world's population. There are many treatment modalities including topical medicines, ultraviolet light therapy, monoclonal antibodies, and several oral medications. Cytokines play a central role in the pathogenesis of this disorder including TNF-α, (tumor necrosis factor-α) IL-17A (interleukin-17A), IL-17F, IL-22, and IL-23. Cytokine signaling involves transduction mediated by the JAK-STAT pathway. There are four JAKS (JAK1/2/3 and TYK2) and six STATS (signal transducer and activators of transcription). Janus kinases contain an inactive JH2 domain that is aminoterminal to the active JH1 domain. Under basal conditions, the JH2 domain inhibits the activity of the JH1 domain. Deucravacitinib is an orally effective N-trideuteromethyl-pyridazine derivative that targets and stabilizes the TYK2 JH2 domain and thereby blocks TYK2 JH1 activity. Seven other JAK inhibitors, which target the JAK family JH1 domain, are prescribed for the treatment of neoplastic and other inflammatory diseases. The use of deuterium in the trimethylamide decreases the rate of demethylation and slows the production of a metabolite that is active against a variety of targets in addition to TYK2. A second unique aspect in the development of deucravacitinib is the targeting of a pseudokinase domain. Deucravacitinib is rather specific for TYK2 and its toxic effects are much less than those of the other FDA-approved JAK inhibitors. The successful development of deucravacitinib may stimulate the development of additional pseudokinase ligands for the JAK family and for other kinase families as well.