Oxidative lipid damage by naringenin selectively sensitizes chronic myeloid leukemia cell lines and patient samples to Bcr-Abl tyrosine kinase inhibitors.

Chronic myeloid leukemia (CML) treatment with Bcr-Abl tyrosine kinase inhibitors (TKIs) has significantly improved patient outcomes, yet challenges such as drug resistance and persistence of leukemic stem cells persist. This study explores the potential of naringenin, a natural flavonoid, to enhance the efficacy of Bcr-Abl TKIs in CML therapy. We showed that naringenin reduces viability of a panel of CML cell lines regardless of varying cellular origin and genetic mutations, and acts synergistically with dasatinib and ponatinib. Importantly, naringenin is effective in targeting blast crisis CML CD34+ cells by decreasing their colony formation, self-renewal and viability. Compared to CML, naringenin is significantly less effective against normal bone marrow (NBM) counterparts. In addition, naringenin significantly enhances the inhibitory effects of dasatinib in CML but not NBM CD34+ cells. Mechanism studies showed that naringenin's inhibitory effects were associated with the induction of oxidative stress and lipid damage, as evidenced by increased reactive oxygen species (ROS) and malondialdehyde (MDA) levels. Notably, naringenin upregulated genes related to mitochondrial biogenesis while downregulating antioxidant defense genes. Pretreatment with α-tocopherol, which inhibits lipid-mediated ROS production, completely abolished the ROS increase and restored cell viability, indicating that lysosomal lipid peroxidation plays a crucial role in naringenin's mechanism of action. In a CML xenograft mouse model, the combination of naringenin and dasatinib resulted in remarkably more tumor growth suppression compared to single drug alone. Importantly, this combination was well-tolerated, with no adverse effects on body weight observed. These findings suggest that naringenin, by inducing oxidative lipid damage, enhances the anti-leukemic effects of Bcr-Abl TKIs, offering a promising therapeutic strategy for CML.

Computational insights into inhibiting EphA2: Integrating structure-based virtual screening, docking, and molecular dynamics simulations for small molecule discovery.

Elevated expression and dysfunction of ephrin type A receptor-2 (EphA2) have been implicated in the initiation and progression of cancer, metastasis, and unfavorable clinical outcomes. A promising strategy to counteract this dysregulation involves the development of small-molecule inhibitors that target EphA2. Our study focuses on this objective. To initiate Structure-Based Virtual Screening (SBVS), we leveraged an advanced online platform, the Mcule database, which houses an extensive collection of millions of chemical compounds. Using drug similarity filters, we efficiently identified ten thousand potential hits. By further refining the selection through toxicity profiling, we prudently narrowed down the candidates to a more manageable set of 100 molecules. Using the Mcule Single Click, DockThor, and SwissDock tools, we conducted multi-scoring docking assessments of thirty-seven compounds that satisfied the ADME standards. A comprehensive evaluation of Gibbs binding free energy terms, as derived from these docking tools, facilitated the identification of top-ranking docking hits. Remarkably, among the known inhibitors, dasatinib displayed the most robust binding to EphA2 with an average ΔG of -9.0 kcal/mol. Intriguingly, alternatives have emerged in recent years. Notably, small molecules such as Mcule-1579910267 (ΔG: -9.3 kcal/mol), Mcule-1893218381 (ΔG: -9.2 kcal/mol), Mcule-3981378344 (ΔG: -9.3 kcal/mol), and Mcule-8617639093 (ΔG: -9.1 kcal/mol) exhibited a notably strong binding affinity to EphA2, rivaling dasatinib. Subsequently, the four leading ligands along with dasatinib were selected for the MD simulations. Our rigorous analyses during the MD simulation phase encompassing RMSD, RMSF, SASA, ΔGsolv, and Rg underscored the favorable stability of Mcule-8617639093. This compelling evidence ultimately signifies the potential for selective EphA2 inhibition.

A SRC-slug-TGFß2 signaling axis drives poor outcomes in triple-negative breast cancers.

BACKGROUND: Treatment options for the Triple-Negative Breast Cancer (TNBC) subtype remain limited and the outcome for patients with advanced TNBC is very poor. The standard of care is chemotherapy, but approximately 50% of tumors develop resistance. METHODS: We performed gene expression profiling of 58 TNBC tumor samples by microarray, comparing chemosensitive with chemoresistant tumors, which revealed that one of the top upregulated genes was TGFß2. A connectivity mapping bioinformatics analysis predicted that the SRC inhibitor Dasatinib was a potential pharmacological inhibitor of chemoresistant TNBCs. Claudin-low TNBC cell lines were selected to represent poor-outcome, chemoresistant TNBC, for in vitro experiments and in vivo models. RESULTS: In vitro, we identified a signaling axis linking SRC, AKT and ERK2, which in turn upregulated the stability of the transcription factors, Slug and Snail. Slug was shown to repress TGFß2-antisense 1 to promote TGFß2 signaling, upregulating cell survival via apoptosis and DNA-damage responses. Additionally, an orthotopic allograft in vivo model demonstrated that the SRC inhibitor Dasatinib reduced tumor growth as a single agent, and enhanced responses to the TNBC mainstay drug, Epirubicin. CONCLUSION: Targeting the SRC-Slug-TGFß2 axis may therefore lead to better treatment options and improve patient outcomes in this highly aggressive subpopulation of TNBCs.

In our study, we focused on a particular subtype of aggressive breast cancer called Triple-Negative Breast Cancer (TNBC). We investigated a complex series of events that contribute to poor outcomes in this disease and uncovered a crucial signaling cascade driving tumor growth and progression.At the core of this signaling cascade are three key proteins: SRC, AKT, and ERK2. Together, they form a pathway that activates a transcription factor called Slug. Transcription factors act like molecular switches, controlling the expression of genes. Once Slug is activated, it strongly suppresses genes that would normally restrict cell growth and cell spread.One of the genes downregulated by Slug is TGFB2-AS1. This product of the TGFB2-AS1 gene normally controls levels of its target protein called TGF-beta2 (TGFB2), a protein which has roles in cell growth, cell migration and differentiation. Slug downregulation of TGFB2-AS1 results in higher TGFB2 levels, and this in turn contributes to the uncontrolled growth and spread of cancer cells. TGFB2, and other proteins in this pathway (SRC, AKT, ERK2, and a Slug interactor called LSD1) all maintain the stability of Slug, meaning that Slug levels remain high and drive the aggressive features of this subtype of breast cancer.Overall, our research sheds light on the intricate molecular mechanisms driving aggressive TNBC. It also identifies potential targets for future therapies, aimed at disrupting this harmful signaling pathway and potentially improving patient outcomes for this disease.

A comprehensive single-cell RNA transcriptomic analysis identifies a unique SPP1+ macrophages subgroup in aging skeletal muscle.

Senescence of skeletal muscle (SkM) has been a primary contributor to senior weakness and disability in recent years. The gradually declining SkM function associated with senescence has recently been connected to an imbalance between damage and repair. Macrophages (Mac) are involved in SkM aging, and different macrophage subgroups hold different biological functions. Through comprehensive single-cell transcriptomic analysis, we first compared the metabolic pathways and biological functions of different types of cells in young (Y) and old (O) mice SkM. Strikingly, the Mac population in mice SkM was also explored, and we identified a unique Mac subgroup in O SkM characterized by highly expressed SPP1 with strong senescence and adipogenesis features. Further work was carried out on the metabolic and biological processes for these Mac subgroups. Besides, we verified that the proportion of the SPP1+ Mac was increased significantly in the quadriceps tissues of O mice, and the senotherapeutic drug combination dasatinib + quercetin (D + Q) could dramatically reduce its proportion. Our study provides novel insight into the potential role of SPP1+ Mac in SkM, which may serve as a senotherapeutic target in SkM aging.

Effects of intermittent senolytic therapy on bone metabolism in postmenopausal women: a phase 2 randomized controlled trial.

Preclinical evidence demonstrates that senescent cells accumulate with aging and that senolytics delay multiple age-related morbidities, including bone loss. Thus, we conducted a phase 2 randomized controlled trial of intermittent administration of the senolytic combination dasatinib plus quercetin (D + Q) in postmenopausal women (n = 60 participants). The primary endpoint, percentage changes at 20 weeks in the bone resorption marker C-terminal telopeptide of type 1 collagen (CTx), did not differ between groups (median (interquartile range), D + Q -4.1% (-13.2, 2.6), control -7.7% (-20.1, 14.3); P = 0.611). The secondary endpoint, percentage changes in the bone formation marker procollagen type 1 N-terminal propeptide (P1NP), increased significantly (relative to control) in the D + Q group at both 2 weeks (+16%, P = 0.020) and 4 weeks (+16%, P = 0.024), but was not different from control at 20 weeks (-9%, P = 0.149). No serious adverse events were observed. In exploratory analyses, the skeletal response to D + Q was driven principally by women with a high senescent cell burden (highest tertile for T cell p16 (also known as CDKN2A) mRNA levels) in which D + Q concomitantly increased P1NP (+34%, P = 0.035) and reduced CTx (-11%, P = 0.049) at 2 weeks, and increased radius bone mineral density (+2.7%, P = 0.004) at 20 weeks. Thus, intermittent D + Q treatment did not reduce bone resorption in the overall group of postmenopausal women. However, our exploratory analyses indicate that further studies are needed testing the hypothesis that the underlying senescent cell burden may dictate the clinical response to senolytics. ClinicalTrials.gov identifier: NCT04313634 .

Syngeneic mouse model of YES-driven metastatic and proliferative hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is a disease of high unmet medical need that has become a global health problem. The development of targeted therapies for HCC has been hindered by the incomplete understanding of HCC pathogenesis and the limited number of relevant preclinical animal models. We recently unveiled a previously uncharacterized YES kinase (encoded by YES1)-dependent oncogenic signaling pathway in HCC. To model this subset of HCC, we established a series of syngeneic cell lines from liver tumors of transgenic mice expressing activated human YES. The resulting cell lines (referred to as HepYF) were enriched for expression of stem cell and progenitor markers, proliferated rapidly, and were characterized by high SRC family kinase (SFK) activity and activated mitogenic signaling pathways. Transcriptomic analysis indicated that HepYF cells are representative of the most aggressive proliferation class G3 subgroup of HCC. HepYF cells formed rapidly growing metastatic tumors upon orthotopic implantation into syngeneic hosts. Treatment with sorafenib or the SFK inhibitor dasatinib markedly inhibited the growth of HepYF tumors. The new HepYF HCC cell lines provide relevant preclinical models to study the pathogenesis of HCC and test novel small-molecule inhibitor and immunotherapy approaches.

Influence of Tyrosine Kinase Inhibitors and Everolimus on TGFß1 and TGF-ß Receptor 2 in Squamous Cell Carcinoma Cells.

BACKGROUND/AIM: Transforming growth factor-ß (TGF-ß) plays a significant role in the formation of different cancer subtypes. There is evidence that TGF-ß pathways promote cancerogenic cell characteristics but also have tumor-suppressor capabilities. The tyrosine kinase inhibitors nilotinib, dasatinib, erlotinib, gefitinib, and everolimus are approved as targeted therapies for several tumor entities, including head and neck squamous cell carcinoma (HNSCC). This study aimed to investigate the effects of these substances on the expression levels of TGFß1 and TGF-ß receptor type 2 (TGFßR2) in HPV-negative and HPV-positive SCC cell cultures. MATERIALS AND METHODS: Expression patterns of TGFß1 and TGFßR2 were determined using enzyme-linked immunosorbent assay (ELISA) in three HNSCC cell lines (i.e., HNSCC-11A, HNSCC-14C, and CERV196). These cells were incubated with nilotinib, dasatinib, erlotinib, gefitinib, and everolimus (20 µmol/l) and compared to a chemonaive control. An assessment of concentration levels was conducted after 24, 48, 72, and 96 h of treatment. RESULTS: Statistically significant changes in the expression levels of TGFß1 and TGFßR2 were found in all tested cell cultures (p<0.05) compared to the negative control. An increase in TGFß-R2 expression was detected after treatment with most of the tested tyrosine kinase inhibitors, whereas a reduction in TGFß1 was observed. The addition of everolimus had the opposite effect on both TGFßR2 and TGF-B1- expression. CONCLUSION: Expression of TGFß1 and TGFßR2 was detected in all cultured HNSCC cell lines. Nilotinib, dasatinib, erlotinib, gefitinib, and everolimus had an impact on the expression levels of TGFß1 and TGFßR2 in vitro.

ASP210: a potent oligonucleotide-based inhibitor effective against TKI-resistant CML cells.

Clinical experience with tyrosine kinase inhibitors (TKIs) over the past two decades has shown that, despite the apparent therapeutic benefit, nearly 30% of patients with chronic myelogenous leukemia (CML) display primary resistance or intolerance to TKIs, and approximately 25% of those treated are forced to switch TKIs at least once during therapy due to acquired resistance. Safe and effective treatment modalities targeting leukemic clones that escape TKI therapy could hence be game changers in the professional management of these patients. Here, we aimed to investigate the efficacy of a novel therapeutic oligonucleotide of unconventional design, called ASP210, to reduce BCR-ABL1 mRNA levels in TKI-resistant CML cells, with the assumption of inducing their apoptosis. Imatinib- and dasatinib-resistant sublines of BCR-ABL1-positive MOLM-7 and CML-T1 cells were established and exposed to 0.25 and 2.5 µM ASP210 for 10 days. RT-qPCR showed a remarkable reduction of the target mRNA level by >99% after a single application. Cell viability was monitored daily by trypan blue staining. In response to the lack of driver oncoprotein BCR-ABL1, TKI-resistant CML cells underwent apoptosis regardless of the presence of the clinically relevant T315I mutation by day 5 after redosing with ASP210. The effect was selective for cancer cells, indicating a favorable safety profile for this therapeutic modality. Furthermore, the spontaneous uptake and high intracellular concentrations of ASP210 suggest its potential to be effective at relatively low doses. The present findings suggest that ASP210 is a promising therapeutic avenue for patients with CML who fail to respond to TKI therapy.NEW & NOTEWORTHY Effective treatment modalities targeting leukemic clones that escape tyrosine kinase inhibitor (TKI) therapy could be game changers in the professional management of patients displaying primary resistance, intolerance, or acquired resistance to TKIs. Although delivering authentic innovations today is more complex than ever, we developed a highly potent and safe oligonucleotide-based modality against BCR-ABL1 mRNA named ASP210 that effectively induces cell death in BCR-ABL1-positive TKI-resistant cells while sparing BCR-ABL1-negative healthy cells.

Dasatinib promotes muscle differentiation and disrupts normal muscle regeneration.

Dasatinib is one of the second-generation tyrosine kinase inhibitors used to treat chronic myeloid leukemia and has a broad target spectrum, including KIT, PDGFR, and SRC family kinases. Due to its broad drug spectrum, dasatinib has been reported at the basic research level to improve athletic performance by eliminating senescent cell removal and to have an effect on muscle diseases such as Duchenne muscular dystrophy, but its effect on myoblasts has not been investigated. In this study, we evaluated the effects of dasatinib on skeletal muscle both under normal conditions and in the regenerating state. Dasatinib suppressed the proliferation and promoted the fusion of C2C12 myoblasts. During muscle regeneration, dasatinib increased the gene expressions of myogenic-related genes (Myod, Myog, and Mymx), and caused abnormally thin muscle fibers on the CTX-induced muscle injury mouse model. From these results, dasatinib changes the closely regulated gene expression pattern of myogenic regulatory factors during muscle differentiation and disrupts normal muscle regeneration. Our data suggest that when using dasatinib, its effects on skeletal muscle should be considered, particularly at regenerating stages.

SRC inhibition enables formation of a growth suppressive MAGI1-PP2A complex in isocitrate dehydrogenase-mutant cholangiocarcinoma.

Intrahepatic cholangiocarcinoma (ICC) is an aggressive bile duct malignancy that frequently exhibits isocitrate dehydrogenase (IDH1/IDH2) mutations. Mutant IDH (IDHm) ICC is dependent on SRC kinase for growth and survival and is hypersensitive to inhibition by dasatinib, but the molecular mechanism underlying this sensitivity is unclear. We found that dasatinib reduced p70 S6 kinase (S6K) and ribosomal protein S6 (S6), leading to substantial reductions in cell size and de novo protein synthesis. Using an unbiased phosphoproteomic screen, we identified membrane-associated guanylate kinase, WW, and PDZ domain containing 1 (MAGI1) as an SRC substrate in IDHm ICC. Biochemical and functional assays further showed that SRC inhibits a latent tumor-suppressing function of the MAGI1-protein phosphatase 2A (PP2A) complex to activate S6K/S6 signaling in IDHm ICC. Inhibiting SRC led to activation and increased access of PP2A to dephosphorylate S6K, resulting in cell death. Evidence from patient tissue and cell line models revealed that both intrinsic and extrinsic resistance to dasatinib is due to increased phospho-S6 (pS6). To block pS6, we paired dasatinib with the S6K/AKT inhibitor M2698, which led to a marked reduction in pS6 in IDHm ICC cell lines and patient-derived organoids in vitro and substantial growth inhibition in ICC patient-derived xenografts in vivo. Together, these results elucidated the mechanism of action of dasatinib in IDHm ICC, revealed a signaling complex regulating S6K phosphorylation independent of mTOR, suggested markers for dasatinib sensitivity, and described a combination therapy for IDHm ICC that may be actionable in the clinic.

Targeted Clearance of Senescent Cells Via Engineered Extracellular Vesicles Reprograms Tumor Immunosuppressive Microenvironment.

Unravelling the mechanisms for the immunosuppressive tumor microenvironment and developing corresponding therapeutic strategies are of great importance to improve the cancer immunotherapy. This study has revealed that there are abundant senescent cells accumulated in the colon cancer tissue, which contributes greatly to the immunosuppressive microenvironment. Oral delivery of Dasatinib and Quercetin (D+Q) eliminates the senescent cells with compromised efficiency due to the poor tumor penetration and short half-life. To improve the efficacy of senescent cell clearance, this work has developed an extracellular vesicle (EV) based senolytic strategy. The engineered senolytic EVs have anti-GPNMB (a senescent cell surface marker) displayed on the surface and D+Q loaded on the membrane. In a syngeneic mouse model, senolytic EVs efficiently and selectively eradicate the senescent cells and in turn unleashes the antitumor immunity. With the antitumor immunity boosted, cancer growth is inhibited and the survival is prolonged. In summary, this work has illuminated that senescent cells contribute to the immunosuppressive microenvironment in colon cancer and proposes a novel strategy to conquer the problem by EV-based senolytics.

A physiologically-based pharmacokinetic precision dosing approach to manage dasatinib drug-drug interactions.

Dasatinib, a second-generation tyrosine kinase inhibitor, is approved for treating chronic myeloid and acute lymphoblastic leukemia. As a sensitive cytochrome P450 (CYP) 3A4 substrate and weak base with strong pH-sensitive solubility, dasatinib is susceptible to enzyme-mediated drug-drug interactions (DDIs) with CYP3A4 perpetrators and pH-dependent DDIs with acid-reducing agents. This work aimed to develop a whole-body physiologically-based pharmacokinetic (PBPK) model of dasatinib to describe and predict enzyme-mediated and pH-dependent DDIs, to evaluate the impact of strong and moderate CYP3A4 inhibitors and inducers on dasatinib exposure and to support optimized dasatinib dosing. Overall, 63 plasma profiles from perorally administered dasatinib in healthy volunteers and cancer patients were used for model development. The model accurately described and predicted plasma profiles with geometric mean fold errors (GMFEs) for area under the concentration-time curve from the first to the last timepoint of measurement (AUClast) and maximum plasma concentration (Cmax) of 1.27 and 1.29, respectively. Regarding the DDI studies used for model development, all (8/8) predicted AUClast and Cmax ratios were within twofold of observed ratios. Application of the PBPK model for dose adaptations within various DDIs revealed dasatinib dose reductions of 50%-80% for strong and 0%-70% for moderate CYP3A4 inhibitors and a 2.3-3.1-fold increase of the daily dasatinib dose for CYP3A4 inducers to match the exposure of dasatinib administered alone. The developed model can be further employed to personalize dasatinib therapy, thereby help coping with clinical challenges resulting from DDIs and patient-related factors, such as elevated gastric pH.

Combination of Dasatinib and Quercetin alleviates heat stress-induced cognitive deficits in aged and young adult male mice.

OBJECTIVE: Dasatinib and quercetin (D & Q) have demonstrated promise in improving aged-related pathophysiological dysfunctions in humans and mice. Herein we aimed to ascertain whether the heat stress (HS)-induced cognitive deficits in aged or even young adult male mice can be reduced by D & Q therapy. METHODS: Before the onset of HS, animals were pre-treated with D & Q or placebo for 3 consecutive days every 2 weeks over a 10-week period. Cognitive function, intestinal barrier permeability, and blood-brain barrier permeability were assessed. RESULTS: Compared to the non-HS young adult male mice, the HS young adult male mice or the aged male mice had significantly lesser extents of the exacerbated stress reactions, intestinal barrier disruption, endotoxemia, systemic inflammation and oxidative stress, blood-brain barrier disruption, hippocampal inflammation and oxidative stress, and cognitive deficits evaluated at 7 days post-HS. All the cognitive deficits and other syndromes that occurred in young adult HS mice or in aged HS mice were significantly attenuated by D & Q therapy (P < 0.01). Compared to the young adult HS mice, the aged HS mice had significantly (P < 0.01) higher severity of cognitive deficits and other related syndromes. CONCLUSIONS: First, our data show that aged male mice are more vulnerable to HS-induced cognitive deficits than those of the young adult male mice. Second, we demonstrate that a combination of D and Q therapy attenuates cognitive deficits in heat stressed aged or young adult male mice via broad normalization of the brain-gut-endotoxin axis function.

Mix and Shake: A Mild Way to Drug-Loaded Lysozyme Nanoparticles.

Biocompatible nanoparticles as drug carriers can improve the therapeutic efficiency of hydrophobic drugs. However, the synthesis of biocompatible and biodegradable polymeric nanoparticles can be time-consuming and often involves toxic solvents. Here, a simple method for protein-based stable drug-loaded particles with a narrow polydispersity is introduced. In this process, lysozyme is mixed with hydrophobic drugs (curcumin, ellipticine, and dasatinib) and fructose to prepare lysozyme-based drug particles of around 150 nm in size. Fructose is mixed with the drug to generate nanoparticles that serve as templates for the lysozyme coating. The effect of lysozyme on the physicochemical properties of these nanoparticles is studied by transmission electron microscopy (TEM) and scattering techniques (e.g., dynamic light scattering (DLS) and small-angle X-ray scattering (SAXS)). We observed that lysozyme significantly stabilized the curcumin fructose particles for 7 days. Moreover, additional drugs, such as ellipticine and dasatinib, can be loaded to form dual-drug particles with narrow polydispersity and spherical morphology. The results also reveal that lysozyme dual ellipticine/dasatinib curcumin particles enhance the cytotoxicity and uptake on MCF-7 cells, RAW 264.7 cells, and U-87 MG cells due to the larger and rigid hydrophobic core. In summary, lysozyme in combination with fructose and curcumin can serve as a powerful combination to form protein-based stable particles for the delivery of hydrophobic drugs.

Co-assembly of cisplatin and dasatinib in hyaluronan nanogel to combat triple negative breast cancer with reduced side effects.

Treatment for triple negative breast cancer (TNBC) remains a huge challenge due to the lack of targeted therapeutics and tumor heterogenicity. Cisplatin (Cis) have demonstrated favorable therapeutic response in TNBC and thus is used together with various kinase inhibitors to fight the heterogenicity of TNBC. The combination of Cis with SRC inhibitor dasatinib (DAS) has shown encouraging anti-TNBC efficacy although the additive toxicity was commonly observed. To overcome the severe side effects of this Cis involved therapy, here we co-encapsulated Cis and DAS into a self-assembled hyaluronan (HA) nanogel (designated as HA/Cis/DAS (HCD) nanogel) to afford the TNBC targeted delivery by using the 4T1 mouse model. The acquired HCD nanogel was around 181 nm in aqueous solution, demonstrating the pharmacological activities of both Cis and DAS. Taking advantages of HA's targeting capability towards CD44 that is overexpressed on many TNBC cells, the HCD could well maintain the anticancer efficacy of the Cis and DAS combination, significantly increase the maximum tolerated dose and relieve the renal toxicity in vivo. The current HCD nanogel provides a potent strategy to improve the therapeutic outcome of Cis and DAS combination and thus representing a new targeted treatment option for TNBC.

Senolytic combination of dasatinib and quercetin attenuates renal damage in diabetic kidney disease.

BACKGROUND: Senolytic combination of dasatinib and quercetin (DQ) is the most studied senolytics drugs used to treat various age-related diseases. However, its protective activity against diabetic kidney disease (DKD) and underlying mechanisms are uncertain. PURPOSE: To investigate the functions and potential mechanisms of the senolytics DQ on DKD. METHODS: Diabetic db/db mice were administrated DQ or transfected with over-expressed PPARα or shPPARα vector. The positive control group was administered irbesartan. Renal function and fibrotic changes in kidney tissue were tested. Single-cell RNA-seq (scRNA-seq) was conducted to analyze the differential transcriptome between the diabetic and control mice. Molecular docking simulation was used to assess the combination of DQ and potential factors. Moreover, tubular epithelial cells under high-glucose (HG) conditions were incubated with DQ and transfected with or without over-expressed PPARα/siPPARα vector. RESULTS: DQ significantly improved renal function, histopathological and fibrotic changes, alleviated lipid deposition, and increased ATP levels in mice with DKD. DQ reduced multiple fatty acid oxidation (FAO) pathway-related proteins and up-regulated PPARα in db/db mice. Overexpression of PPARα upregulated the expression of PPARα-targeting downstream FAO pathway-related proteins, restored renal function, and inhibited renal fibrosis in vitro and in vivo. Moreover, molecular docking and dynamics simulation analyses indicated the nephroprotective effect of DQ via binding to PPARα. Knockdown of PPARα reversed the effect of DQ on the FAO pathway and impaired the protective effect of DQ during DKD. CONCLUSION: For the first time, DQ was found to exert a renal protective effect by binding to PPARα and attenuating renal damage through the promotion of FAO in DKD.

Multiaction Pt(IV) Prodrugs Releasing Cisplatin and Dasatinib Are Potent Anticancer and Anti-Invasive Agents Displaying Synergism between the Two Drugs.

Herein, we describe the general design, synthesis, characterization, and biological activity of new multitargeting Pt(IV) prodrugs that combine antitumor cisplatin and dasatinib, a potent inhibitor of Src kinase. These prodrugs exhibit impressive antiproliferative and anti-invasive activities in tumor cell lines in both two-dimensional (2D) monolayers of cell cultures and three-dimensional (3D) spheroids. We show that the cisplatin moiety and dasatinib in the investigated Pt(IV) complexes are both involved in the mechanism of action in MCF7 breast cancer cells and act synergistically. Thus, combining dasatinib and cisplatin into one molecule, compared to using individual components in a mix, may bring several advantages, such as significantly higher activity in cancer cell lines and higher selectivity for tumor cells. Most importantly, Pt(IV)-dasatinib complexes hold significant promise for potential anticancer therapies by targeting epithelial-mesenchymal transition, thus preventing the spread and metastasis of tumors, a value unachievable by a simple combination of both individual components.

Nanoformulation of dasatinib cannot overcome therapy resistance of pancreatic cancer cells with low LYN kinase expression.

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) is one of the most difficult to treat tumors. The Src (sarcoma) inhibitor dasatinib (DASA) has shown promising efficacy in preclinical studies of PDAC. However, clinical confirmation could not be achieved. Overall, our aim was to deliver arguments for the possible reinitiating clinical testing of this compound in a biomarker-stratifying therapy trial for PDAC patients. We tested if the nanofunctionalization of DASA can increase the drug efficacy and whether certain Src members can function as clinical predictive biomarkers. METHODS: Methods include manufacturing of poly(vinyl alcohol) stabilized gold nanoparticles and their drug loading, dynamic light scattering, transmission electron microscopy, thermogravimetric analysis, Zeta potential measurement, sterile human cell culture, cell growth quantification, accessing and evaluating transcriptome and clinical data from molecular tumor dataset TCGA, as well as various statistical analyses. RESULTS: We generated homo-dispersed nanofunctionalized DASA as an AuNP@PVA-DASA conjugate. The composite did not enhance the anti-growth effect of DASA on PDAC cell lines. The cell model with high LYN expression showed the strongest response to the therapy. We confirm deregulated Src kinetome activity as a prevalent feature of PDAC by revealing mRNA levels associated with higher malignancy grade of tumors. BLK (B lymphocyte kinase) expression predicts shorter overall survival of diabetic PDAC patients. CONCLUSIONS: Nanofunctionalization of DASA needs further improvement to overcome the therapy resistance of PDAC. LYN mRNA is augmented in tumors with higher malignancy and can serve as a predictive biomarker for the therapy resistance of PDAC cells against DASA. Studying the biological roles of BLK might help to identify underlying molecular mechanisms associated with PDAC in diabetic patients.

Targeting pathological cells with senolytic drugs reduces seizures in neurodevelopmental mTOR-related epilepsy.

Cortical malformations such as focal cortical dysplasia type II (FCDII) are associated with pediatric drug-resistant epilepsy that necessitates neurosurgery. FCDII results from somatic mosaicism due to post-zygotic mutations in genes of the PI3K-AKT-mTOR pathway, which produce a subset of dysmorphic cells clustered within healthy brain tissue. Here we show a correlation between epileptiform activity in acute cortical slices obtained from human surgical FCDII brain tissues and the density of dysmorphic neurons. We uncovered multiple signatures of cellular senescence in these pathological cells, including p53/p16 expression, SASP expression and senescence-associated ß-galactosidase activity. We also show that administration of senolytic drugs (dasatinib/quercetin) decreases the load of senescent cells and reduces seizure frequency in an MtorS2215F FCDII preclinical mouse model, providing proof of concept that senotherapy may be a useful approach to control seizures. These findings pave the way for therapeutic strategies selectively targeting mutated senescent cells in FCDII brain tissue.

High throughput screening identifies dasatinib as synergistic with trametinib in low grade serous ovarian carcinoma.

BACKGROUND: Low grade serous ovarian carcinoma (LGSOC) is a distinct histotype of ovarian cancer characterised high levels of intrinsic chemoresistance, highlighting the urgent need for new treatments. High throughput screening in clinically-informative cell-based models represents an attractive strategy for identifying candidate treatment options for prioritisation in clinical studies. METHODS: We performed a high throughput drug screen of 1610 agents across a panel of 6 LGSOC cell lines (3 RAS/RAF-mutant, 3 RAS/RAF-wildtype) to identify novel candidate therapeutic approaches. Validation comprised dose-response analysis across 9 LGSOC models and 5 high grade serous comparator lines. RESULTS: 16 hits of 1610 screened compounds were prioritised for validation based on >50% reduction in nuclei counts in over half of screened cell lines at 1000 nM concentration. 11 compounds passed validation, and the four agents of greatest interest (dasatinib, tyrosine kinase inhibitor; disulfiram, aldehyde dehydrogenase inhibitor; carfilzomib, proteasome inhibitor; romidepsin, histone deacetylase inhibitor) underwent synergy profiling with the recently approved MEK inhibitor trametinib. Disulfiram demonstrated excellent selectivity for LGSOC versus high grade serous ovarian carcinoma comparator lines (P = 0.003 for IC50 comparison), while the tyrosine kinase inhibitor dasatinib demonstrated favourable synergy with trametinib across multiple LGSOC models (maximum zero interaction potency synergy score 46.9). The novel, highly selective Src family kinase (SFK) inhibitor NXP900 demonstrated a similar trametinib synergy profile to dasatinib, suggesting that SFK inhibition is the likely driver of synergy. CONCLUSION: Dasatinib and other SFK inhibitors represent novel candidate treatments for LGSOC and demonstrate synergy with trametinib. Disulfiram represents an additional treatment strategy worthy of investigation.