Search Results (137)

Although PD-1/PD-L1 inhibitors have transformed cancer immunotherapy, a substantial proportion of patients derive no clinical benefit due to resistance driven by the tumour microenvironment (TME). Transforming growth factor-β (TGF-β) is a key immunosuppressive cytokine implicated in this resistance. Several bifunctional antibodies that co-target PD-1 and TGF-β signalling have entered clinical trials and shown encouraging efficacy, but the mechanistic basis of their synergy is not fully understood. Here, we engineered 015s, a bifunctional fusion antibody that simultaneously targets murine PD-1 and TGF-β and evaluated its antitumour efficacy and mechanistic impact in pre-clinical models. Antibody 015s exhibited high affinity, dual target binding, and the effective inhibition of PD-1 and TGF-β signalling. In vivo, 015s significantly suppressed tumour growth compared with anti-mPD-1 or TGF-β receptor II (TGF-βRII) monotherapy. When combined with the CD24-targeted ADC, 015s produced even greater antitumour activity and achieved complete tumour regression. Mechanistic studies demonstrated that 015s significantly reduced tumour cell migration and invasion, reversed epithelial–mesenchymal transition (EMT), decreased microvascular density, and attenuated collagen deposition within the TME. Antibody 015s also decreased bioactive TGF-β1 and increased intratumoural IFN-γ, creating a more immunostimulatory milieu. These findings support further development of PD-1/TGF-β bifunctional antibodies for cancers with high TGF-β activity or limited response to immune checkpoint blockade. Full article

This study aimed to investigate the tyrosine kinase inhibitor Nintedanib and its potential role in reversing epithelial–mesenchymal transition (EMT) induced by transforming growth factor beta 2 (TGF-β2) in retinal pigment epithelial (RPE) cells, along with its therapeutic potential using a mouse model of subretinal fibrosis. We hypothesized that the blockade of angiogenesis promoting and fibrosis inducing signaling using the receptor tyrosine kinase inhibitor Nintedanib (OfevTM) can prevent or reverse EMT both in vitro and in our in vivo model of subretinal fibrosis. Primary human retinal pigment epithelial cells (phRPE) and adult retinal pigment epithelial cell line (ARPE-19) cells were treated with TGF-β210 ng/mL for two days followed by four days of Nintedanib (1 µM) incubation. Epithelial and mesenchymal phenotypes were assessed by morphological examination, quantitative real-time polymerase chain reaction(qPCR) (ZO-1, Acta2, FN, and Vim), and immunocytochemistry (ZO-1, vimentin, fibronectin, and αSMA). Metabolites were measured using luciferase-based assays. Extracellular acidification and oxygen consumption rates were measured using the Seahorse XF system. Metabolic-related genes (GLUT1, HK2, PFKFB3, CS, LDHA, LDHB) were evaluated by qPCR. A model of subretinal fibrosis using the two-stage laser-induced method in C57BL/6J mice assessed Nintedanib’s therapeutic potential. Fibro-vascular lesions were examined 10 days later via fluorescence angiography and immunohistochemistry. Both primary and ARPE-19 RPE stimulated with TGF-β2 upregulated expression of fibronectin, αSMA, and vimentin, and downregulation of ZO-1, consistent with morphological changes (i.e., elongation). Glucose consumption, lactate production, and glycolytic reserve were significantly increased in TGF-β2-treated cells, with upregulation of glycolysis-related genes (GLUT1, HK2, PFKFB3, CS). Nintedanib treatment reversed TGF-β2-induced EMT signatures, down-regulated glycolytic-related genes, and normalized glycolysis. Nintedanib intravitreal injection significantly reduced collagen-1+ fibrotic lesion size and Isolectin B4+ neovascularization and reduced vascular leakage in the two-stage laser-induced model of subretinal fibrosis. Nintedanib can induce Mesenchymal-to-Epithelial Transition (MET) in RPE cells and reduce subretinal fibrosis through metabolic reprogramming. Nintedanib can therefore potentially be repurposed to treat retinal fibrosis. Full article

The transforming growth factor-β (TGF-β) signaling pathway is involved in various cellular functions, including immunological response, extracellular matrix formation, differentiation, growth and development, and cell cycle regulation. The TGF β receptor type 1 (TGF-βR1) has emerged as a key component of this pathway, exhibiting significant overexpression in diverse malignancies, including hepatocellular carcinoma, gastric cancer, breast cancer, and colon cancer. Multiple therapeutic targets have been identified for the TGF-β signaling pathway, encompassing antibodies, ligand traps, vaccines, antisense oligonucleotides, and small-molecule TGF-βR1 kinase inhibitors. This review delineates the structural and functional characteristics of the small-molecule TGF-βR1 kinase inhibitors. The inhibitors discussed herein are categorized based on shared pharmacophoric features, notably a five-membered heterocyclic ring linked to three distinct features (R1, R2, and R3). These features interact with amino acids within the selectivity pocket, hinge region, or solvent-exposed area, respectively. These insights contribute to a clearer understanding of the structural requirements for selective TGF-βR1 inhibition. The presented findings in this review article offer a valuable foundation for future drug discovery efforts targeting the TGF-β signaling pathway. Full article

Background: Although endothelial mesenchymal transition (EndMT) has been characterized as a basic process in embryogenesis, EndMT is the mechanism that accelerates the development of cardiovascular diseases, including heart failure, aging, and complications of diabetes or hypertension as well. Endothelial cells lose their distinct markers and take on a mesenchymal phenotype during EndMT, expressing distinct products. Methods: In this study, type 1 Diabetes mellitus (T1DM) was induced in rats with streptozotocin (STZ) by intraperitoneal injection at a 60 mg/kg dose. Diabetic rats were randomly divided into two groups, namely, control and diabetic rats, for 4 weeks. Heart, aorta, and plasma samples were collected at the end of 4 weeks. Sequentially, biochemical parameters, cytokines, reactive oxygen species (ROS), protein expression of EndMT markers (Chemokine C-X-C motif ligand-1 (CXCL-1), vimentin, citrullinated histone H3 (H3Cit), α-smooth muscle actin (α-SMA), and transforming growth factor beta (TGF-β) and versican), components of the extracellular matrix (matrix metalloproteinase 2 (MMP-2), tissue inhibitor of metalloproteinase-1(TIMP-1), and discoidin domain tyrosine kinase receptor 2 (DDR-2)) were detected by ELISA or Western blot, respectively. Results: Cytokines and ROS were increased in diabetic hearts, which induced partial EndMT. Among EndMT markers, histone citrullination, α-SMA, and CXCL-1 were increased; vimentin was decreased in DM. The endothelial marker endothelin-1 was significantly higher in the aortas of DM rats. Interestingly, TGF-β showed a significant decrease in the diabetic heart, plasma, and aorta. Additionally, MMP-2/TIMP-1 levels also decreased in DM. Conclusions: To sum up, the identification of molecules and regulatory pathways involved in EndMT provided novel therapeutic approaches for cardiac pathophysiological conditions. Full article

Hypertension-induced cardiac remodeling is a complex process driven by interconnected molecular and cellular mechanisms that culminate in hypertensive myocardium, characterized by ventricular hypertrophy, fibrosis, impaired angiogenesis, and myocardial dysfunction. This review discusses the histomorphometric changes in capillary density, fibrosis, and mast cells in the hypertensive myocardium and delves into the roles of key regulatory systems, including the apelinergic system, vascular endothelial growth factor (VEGF)/VEGF receptor (VEGFR) pathways, and nitric oxide (NO)/nitric oxide synthase (NOS) signaling in the pathogenesis of hypertensive heart disease (HHD). Capillary rarefaction, a hallmark of HHD, contributes to myocardial ischemia and fibrosis, underscoring the importance of maintaining vascular integrity. Targeting capillary density (CD) through antihypertensive therapy or angiogenic interventions could significantly improve cardiac outcomes. Myocardial fibrosis, mediated by excessive collagen deposition and influenced by fibroblast growth factor-2 (FGF-2) and transforming growth factor-beta (TGF-β), plays a pivotal role in the structural remodeling of hypertensive myocardium. While renin–angiotensin–aldosterone system (RAAS) inhibitors show anti-fibrotic effects, more targeted therapies are needed to address fibrosis directly. Mast cells, though less studied in humans, emerge as critical regulators of cardiac remodeling through their release of pro-fibrotic mediators such as histamine, tryptase, and FGF-2. The apelinergic system emerges as a promising therapeutic target due to its vasodilatory, anti-fibrotic, and cardioprotective properties. The system counteracts the deleterious effects of the RAAS and has demonstrated efficacy in preclinical models of hypertension-induced cardiac damage. Despite its potential, human studies on apelin analogs remain limited, warranting further exploration to evaluate their clinical utility. VEGF signaling plays a dual role, facilitating angiogenesis and compensatory remodeling during the early stages of arterial hypertension (AH) but contributing to maladaptive changes when dysregulated. Modulating VEGF signaling through exercise or pharmacological interventions has shown promise in improving CD and mitigating hypertensive cardiac damage. However, VEGF inhibitors, commonly used in oncology, can exacerbate AH and endothelial dysfunction, highlighting the need for therapeutic caution. The NO/NOS pathway is essential for vascular homeostasis and the prevention of oxidative stress. Dysregulation of this pathway, particularly endothelial NOS (eNOS) uncoupling and inducible NOS (iNOS) overexpression, leads to endothelial dysfunction and nitrosative stress in hypertensive myocardium. Strategies to restore NO bioavailability, such as tetrahydrobiopterin (BH₄) supplementation and antioxidants, hold potential for therapeutic application but require further validation. Future studies should adopt a multidisciplinary approach to integrate molecular insights with clinical applications, paving the way for more personalized and effective treatments for HHD. Addressing these challenges will not only enhance the understanding of hypertensive myocardium but also improve patient outcomes and quality of life. Full article

Studies have consistently shown that long-wave ultraviolet A (UVA) radiation triggers skin photoaging, which is evident as reduced elasticity, a loss of firmness, and signs of aging. There is an urgent need to investigate photoaging mechanisms to devise protective strategies against UVA. The present study aimed to explore the effects of recombinant type XVII collagen on UVA-induced skin aging and uncover its molecular mechanisms, thereby laying a solid theoretical foundation for precise treatments and prevention. We therefore modeled photoaging damage in HaCaT cells and evaluated collagen-related protein and gene expression levels via western blot analysis and real-time quantitative polymerase chain reaction analysis. Immunofluorescent staining was also used to assess collagen secretion and basement membrane protein expression. Recombinant type XVII collagen significantly boosted type IV and type XVII collagen, laminin alpha 5, and integrin β1 production, thus counteracting UVA-induced collagen decline. The polymerase chain reaction analysis revealed matrix metalloproteinase (MMP) downregulation and tissue inhibitor of metalloproteinase (TIMP) upregulation. Modulating the transforming growth factor (TGF)-β/Smad and epidermal growth factor receptor (EGFR)/mitogen-activated protein kinase (MAPK)/activator protein-1 (AP-1) pathways suppressed photoaging. Together, our findings suggest that recombinant type XVII collagen ameliorates UVA-induced damage by reversing MMP and TIMP gene expression, thereby preventing collagen degradation and enhancing basement membrane secretion. These results offer a theoretical basis for potent anti-photoaging products, thus paving the way for innovative solutions against UVA-induced skin aging. Full article

Diabetes is associated with an increased risk of thromboembolism. However, the effects of apixaban, a factor Xa inhibitor on diabetic nephropathy, remain unknown. Six-week-old Wistar rats received a single 60 mg/kg intraperitoneal injection of streptozotocin to produce a model of type 1 diabetes. Type 1 diabetic and non-diabetic control rats were treated with or without apixaban orally for 8 weeks, and blood and kidneys were obtained for biochemical, real-time reverse transcription-polymerase chain reaction (RT-PCR) and morphological analyses. Although apixaban treatment did not affect glycemic or lipid parameters, it significantly (p < 0.01) inhibited the increases in advanced glycation end products (AGEs), the receptor for AGEs (RAGE) mRNA and protein levels, 8-hydroxy-2′-deoxyguanosine (8-OHdG), and NADPH oxidase-driven superoxide generation in diabetic rats at 14 weeks old. Compared with non-diabetic rats, gene and protein expression levels of monocyte chemoattractant protein-1 (MCP-1), vascular cell adhesion molecule-1 (VCAM-1), transforming growth factor-β (TGF-β), connective tissue growth factor (CTGF), and fibronectin were increased in 14-week-old diabetic rats, which were associated with enhanced renal expression of kidney injury molecule-1 (KIM-1) and Mac-3, increased extracellular matrix accumulation in the kidneys, and elevated urinary excretion levels of protein and KIM-1, all of which were significantly inhibited by the treatment with apixaban. Urine KIM-1 levels were significantly (p < 0.01) and positively correlated with AGEs (r = 0.690) and 8-OHdG (r = 0.793) in the kidneys and serum 8-OHdG levels (r = 0.823). Our present findings suggest that apixaban could ameliorate renal injury in streptozotocin-induced type 1 diabetic rats partly by blocking the AGE-RAGE-oxidative stress axis in diabetic kidneys. Full article

Immunotherapy has shown limited efficacy in prostate cancer, largely due to low tumor immunogenicity, sparse tumor-infiltrating lymphocytes, and a suppressive microenvironment. Recent therapeutic strategies aim to boost immune responses and counteract immunosuppressive factors through interventions such as immune checkpoint inhibitors, immunogenic cell death-inducing therapies, and the targeted blockade of pathways like that of transforming growth factor-β. Vaccine-based approaches, potent immune adjuvants, and engineered chimeric antigen receptor (CAR) T cells are also being investigated to overcome local immune inhibitory signals. Advancements in imaging, multi-omic profiling, and liquid biopsies offer promising avenues for real-time monitoring, better patient selection, and precision treatment. This review provides an overview of the key immunosuppressive features of prostate cancer, current immunotherapeutic modalities, and emerging strategies to transform “cold” tumors into more responsive “hot” targets. By integrating these approaches, we may achieve more durable clinical benefits for patients with advanced or metastatic prostate cancer. Full article

Background: Chondrosarcoma (CS) is a highly aggressive primary malignant bone tumor for which there are no effective systemic treatments. We assessed aspartate β-hydroxylase (ASPH) as a potential treatment target. ASPH is a transforming cell surface receptor, but its role in chondrosarcoma has not been evaluated. Our goals were to analyze the expression of ASPH in conventional chondrosarcoma, evaluate its utility as a biomarker, and determine if ASPH inhibition diminishes tumor progression in a preclinical model. Methods: An annotated tissue microarray was constructed with conventional chondrosarcoma tissues. ASPH expression was quantified with immunohistochemistry. A small molecule inhibitor (SMI) designed to inhibit ASPH activity was evaluated in two CS cell lines with intact ASPH expression and after knockout. Cell viability, invasion, and matrix metalloproteinase (MMP) expression were measured. A mouse xenograft chondrosarcoma model was used to evaluate the effect of the SMI on tumor growth, MMP activity in tumors, and lung metastatic burden. Results: Higher ASPH scores were associated with a greater risk of death and metastasis. The SMI decreased CS cell proliferation, invasion, and secretion of MMPs in vitro, and the effects were lost after ASPH knockout. In vivo, systemic administration of the SMI decreased tumor growth, MMP activity and content in xenograft tumors, and lung metastatic burden. Conclusions: These data validate ASPH as a biomarker in CS and as a factor in the metastatic phenotype. Systemic treatment with an SMI directed against ASPH inhibits tumor progression in a preclinical model, suggesting that ASPH-targeted therapy may be a new treatment strategy for chondrosarcoma expressing ASPH. Full article

Primary pulmonary hypertension (PPH), now known as pulmonary arterial hypertension (PAH), has induced significant treatment breakthroughs in the past decade. Treatment has focused on improving patient survival and quality of life, and delaying disease progression. Current therapies are categorized based on targeting different pathways known to contribute to PAH, including endothelin receptor antagonists (ERAs), phosphodiesterase-5 inhibitors (PDE-5 inhibitors), prostacyclin analogs, soluble guanylate cyclase stimulators, and activin signaling inhibitors such as Sotatercept. The latest addition to treatment options is soluble guanylate cyclase stimulators, such as Riociguat, which directly stimulates the nitric oxide pathway, facilitating vasodilation. Looking to the future, advancements in PAH treatment focus on precision medicine involving the sub-stratification of patients through a deep characterization of altered Transforming Growth Factor-β(TGF-β) signaling and molecular therapies. Gene therapy, targeting specific genetic mutations linked to PAH, and cell-based therapies, such as mesenchymal stem cells, are under investigation. Besides prevailing therapies, emerging PH treatments target growth factors and inflammation-modulating pathways, with ongoing trials assessing their long-term benefits and safety. Hence, this review explores current therapies that delay progression and improve survival, as well as future treatments with curative potential. Full article

Endothelial–mesenchymal transition (EnMT) is the transversion of endothelial cells to mesenchymal cells under certain physiological or pathological conditions. When EnMT occurs in the corneal endothelium, corneal endothelial cells (CECs) lose their normal function and thus cannot maintain corneal clarity. Studies have shown that the mechanism of EnMT in CECs involves the transforming growth factor-β (TGF-β) signaling pathway, and one of the important inhibitors of the TGF-β/Smad2/3 pathway is sirtuin-1 (SIRT1). In this study, we used a rat model of corneal endothelium injury and TGF-β1-treated human CECs to induce EnMT, aiming to explore whether SIRT1 activation inhibits corneal EnMT in vivo and in vitro. SIRT1 was activated and suppressed using resveratrol (RSV) and EX527, respectively. The endothelial markers and mesenchymal markers were measured by immunofluorescence and Western blot assays. Co-immunoprecipitation was used to detect the interaction between SIRT1 and Smad2/3. The results showed that after mechanical injury, the group treated with RSV-activated SIRT1 regained corneal transparency and recovered from edema faster than the control group. Moreover, RSV-activated SIRT1 downregulated the expression levels of alpha smooth muscle actin (α-SMA), vimentin, and Snail and upregulated the expression levels of E-cadherin and Na⁺/K⁺-ATPase both in vivo and in vitro, but these effects were reversed when SIRT1 was inhibited by EX527. SIRT1 also upregulated the expression levels of TGF-β receptor 1 and phosphorylated Smad2/3. The interaction between SIRT1 and Smad2/3 in vitro was confirmed by co-immunoprecipitation. Overall, our results indicate that SIRT1 activation inhibits corneal EnMT via the TGF-β/Smad2/3 pathway, which may be a potential therapeutic target for corneal endothelium dysfunction. Full article

Pancreatic ductal adenocarcinoma (PDAC) has an extremely poor prognosis, due in part to early invasion and metastasis, which in turn involves epithelial–mesenchymal transition (EMT) of the cancer cells. Prompted by the discovery that two PDAC cell lines of the quasi-mesenchymal subtype (PANC-1, MIA PaCa-2) exhibit neuroendocrine differentiation (NED), we asked whether NED is associated with EMT. Using real-time PCR and immunoblotting, we initially verified endogenous expressions of various NED markers, i.e., chromogranin A (CHGA), synaptophysin (SYP), somatostatin receptor 2 (SSTR2), and SSTR5 in PANC-1 and MIA PaCa-2 cells. By means of immunohistochemistry, the expressions of CHGA, SYP, SSTR2, and the EMT markers cytokeratin 7 (CK7) and vimentin could be allocated to the neoplastic ductal epithelial cells of pancreatic ducts in surgically resected tissues from patients with PDAC. In HPDE6c7 normal pancreatic duct epithelial cells and in epithelial subtype BxPC-3 PDAC cells, the expression of CHGA, SYP, and neuron-specific enolase 2 (NSE) was either undetectable or much lower than in PANC-1 and MIA PaCa-2 cells. Parental cultures of PANC-1 cells exhibit EM plasticity (EMP) and harbor clonal subpopulations with both M- and E-phenotypes. Of note, M-type clones were found to display more pronounced NED than E-type clones. Inducing EMT in parental cultures of PANC-1 cells by treatment with transforming growth factor-β1 (TGF-β1) repressed epithelial genes and co-induced mesenchymal and NED genes, except for SSTR5. Surprisingly, treatment with bone morphogenetic protein (BMP)-7 differentially affected gene expressions in PANC-1, MIA PaCa-2, BxPC-3, and HPDE cells. It synergized with TGF-β1 in the induction of vimentin, SNAIL, SSTR2, and NSE but antagonized it in the regulation of CHGA and SSTR5. Phospho-immunoblotting in M- and E-type PANC-1 clones revealed that both TGF-β1 and, surprisingly, also BMP-7 activated SMAD2 and SMAD3 and that in M- but not E-type clones BMP-7 was able to dramatically enhance the activation of SMAD3. From these data, we conclude that in EMT of PDAC cells mesenchymal and NED markers are co-regulated, and that mesenchymal–epithelial transition (MET) is associated with a loss of both the mesenchymal and NED phenotypes. Analyzing NED in another tumor type, small cell carcinoma of the ovary hypercalcemic type (SCCOHT), revealed that two model cell lines of this disease (SCCOHT-1, BIN-67) do express CDH1, SNAI1, VIM, CHGA, SYP, ENO2, and SSTR2, but that in contrast to BMP-7, none of these genes was transcriptionally regulated by TGF-β1. Likewise, in BIN-67 cells, BMP-7 was able to reduce proliferation, while in SCCOHT-1 cells this occurred only upon combined treatment with TGF-β and BMP-7. We conclude that in PDAC-derived tumor cells, NED is closely linked to EMT and TGF-β signaling, which may have implications for the therapeutic use of TGF-β inhibitors in PDAC management. Full article

Sepsis remains an important healthcare challenge. The lungs are often affected in sepsis, resulting in acute lung injury characterized by inflammation. Mechanisms involving lipopolysaccharide (LPS) stimulation of toll-like receptor (TLR) signaling with induction of proinflammatory pathways have been implicated in this process. To date, however, studies targeting these pathways have failed to improve outcomes. We have found that LPS may also promote lung injury through the activation of α4 nicotinic acetylcholine receptors (α4 nAChRs) in immune cells. We observed increased expression of α4 nAChRs in human THP-1 monocytic cells exposed to LPS (100 ng/mL, 24 h). We also observed that LPS stimulated the expression of other relevant genes, including tumor necrosis factor-α, interleukin-1β, plasminogen activator inhibitor-1, the solute carrier family 7 member 11, extracellular superoxide dismutase, and transforming growth factor-β1. Of interest, dihydro-β-erythroidine hydrobromide (DHβE), a specific chemical inhibitor of α4 nAChRs, inhibited the LPS-induced expression of these genes. We generated mice with a global knockout mutation of the α4 nAChR subunit in the C57BL/6 background using CRISPR/Cas9 technology. The lungs of these LPS-treated animals demonstrated a reduction in the expression of the above-mentioned genes when compared with the lungs of wild-type animals. In support of the role of oxidative stress, we observed that LPS induced expression of the cystine transporter Slc7a11 in both THP-1 cells and in wild-type mouse lungs. The effects of LPS on THP-1 cells were blocked by the thiol antioxidant N-acetylcysteine and mimicked by redox stress. Importantly, the induction of IL-1β by redox stress was inhibited by the α4 nAChR inhibitor DHβE. Finally, we showed that LPS stimulated calcium influx in THP-1 cells, which was blocked by the α4 nAChR inhibitor. Our observations suggest that LPS promotes lung injury by stimulating redox stress, which activates α4 nAChR signaling and drives proinflammatory cytokine expression. Full article

Background: The spike protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is crucial to viral entry and can cause cardiac injuries. Toll-like receptor 4 (TLR4) and NOD-, LPR-, and pyrin-domain-containing 3 (NLRP3) inflammasome are critical immune system components implicated in cardiac fibrosis. The spike protein activates NLRP3 inflammasome through TLR4 or angiotensin-converting enzyme 2 (ACE2) receptors, damaging various organs. However, the role of spike protein in cardiac fibrosis in humans, as well as its interactions with NLRP3 inflammasomes and TLR4, remain poorly understood. Methods: We utilized scratch assays, Western blotting, and immunofluorescence to evaluate the migration, fibrosis signaling, mitochondrial calcium levels, reactive oxygen species (ROS) production, and cell morphology of cultured human cardiac fibroblasts (CFs) treated with spike (S1) protein for 24 h with or without an anti-ACE2 neutralizing antibody, a TLR4 blocker, or an NLRP3 inhibitor. Results: S1 protein enhanced CFs migration and the expressions of collagen 1, α-smooth muscle actin, transforming growth factor β1 (TGF-β1), phosphorylated SMAD2/3, interleukin 1β (IL-1β), and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB). S1 protein increased ROS production but did not affect mitochondrial calcium content and cell morphology. Treatment with an anti-ACE2 neutralizing antibody attenuated the effects of S1 protein on collagen 1 and TGF-β1 expressions. Moreover, NLRP3 (MCC950) and NF-kB inhibitors, but not the TLR4 inhibitor TAK-242, prevented the S1 protein-enhanced CFs migration and overexpression of collagen 1, TGF-β1, and IL-1β. Conclusion: S1 protein activates human CFs by priming NLRP3 inflammasomes through NF-κB signaling in an ACE2-dependent manner. Full article

Studies conducted on animal models have identified several therapeutic targets for myelofibrosis, the most severe of the myeloproliferative neoplasms. Unfortunately, many of the drugs which were effective in pre-clinical settings had modest efficacy when tested in the clinic. This discrepancy suggests that treatment for this disease requires combination therapies. To rationalize possible combinations, the efficacy in the Gata1^low model of drugs currently used for these patients (the JAK1/2 inhibitor Ruxolitinib) was compared with that of drugs targeting other abnormalities, such as p27kip1 (Aplidin), TGF-β (SB431542, inhibiting ALK5 downstream to transforming growth factor beta (TGF-β) signaling and TGF-β trap AVID200), P-selectin (RB40.34), and CXCL1 (Reparixin, inhibiting the CXCL1 receptors CXCR1/2). The comparison was carried out by expressing the endpoints, which had either already been published or had been retrospectively obtained for this study, as the fold change of the values in the corresponding vehicles. In this model, only Ruxolitinib was found to decrease spleen size, only Aplidin and SB431542/AVID200 increased platelet counts, and with the exception of AVID200, all the inhibitors reduced fibrosis and microvessel density. The greatest effects were exerted by Reparixin, which also reduced TGF-β content. None of the drugs reduced osteopetrosis. These results suggest that future therapies for myelofibrosis should consider combining JAK1/2 inhibitors with drugs targeting hematopoietic stem cells (p27Kip1) or the pro-inflammatory milieu (TGF-β or CXCL1). Full article