Chronic myeloid leukaemia with soft tissue mass formed by mature granulocytes.

Extramedullary lesions in patients with chronic myeloid leukaemia (CML) suggest progression to the blast phase because such lesions generally consist of immature granulocytes. We here report a case of an extramedullary mass formed by mature granulocytes during the chronic phase of CML. A 60-year-old woman who had discontinued treatment for CML with dasatinib of her own accord several years ago presented to our hospital with a complaint of right thigh pain. She had a mass on her right leg, which was located on her right thigh and was elastic, soft and fist-sized. Blood tests and the bone marrow findings were compatible with the chronic phase of CML, and a CT-guided needle biopsy showed an infiltrate containing numerous mature neutrophils and foam cells. The mass disappeared with dasatinib alone, without antibacterial agents or drainage.Although the detailed pathogenesis of mass formation with mature granulocytes in the chronic phase of CML has not been elucidated, the clinical course of the current case highlights the importance of prompt biopsy, pathological examination and the early initiation of appropriate treatment.

Magnetic Rubber@Ni-Co layered double hydroxide derived from ZIF-67 template as nanostructured sorbent; application in determination of anticancer drugs in plasma samples.

In this study, a magnetic three-dimensional nano-composite based on Rubber-Fe3O4@Ni-Co Layered double hydroxide derived from ZIF-67 template was synthesized by a hydrothermal method. The proposed nano-composite was used as a sorbent for the enrichment of trace amounts of anti-cancer drugs (dasatinib and erlotinib hydrochloride) from plasma samples followed by determination using high-performance liquid chromatographic analysis (HPLC-UV). The synthesized nano-sorbent was characterized by X-ray diffraction, field emission scanning electron microscopy, Fourier transform infrared spectroscopy, vibrating-sample magnetometer, Brunauer-Emmett-Teller surface analysis, Barrett-Joyner-Halenda pore size analysis and energy dispersive X-ray spectroscopy. Under optimal experimental conditions, factors affecting on extraction efficiency such as pH, ionic strength, extraction temperature and time, desorption solvent and time, the limit of detection (LODs) and the limit of quantification (LOQs) were obtained as 0.6, 2 µg/L for both of dasatinib and erlotinib, respectively. Also, linear range of the method were 2-500 and 2-1000 µg/L for dasatinib and erlotinib, respectively. Relative standard deviations (RSD%) for the repeatability of extraction on sorbent to sorbent were obtained as 3.59, 1.97 %, and one sorbent reusability were investigated and relative standard deviation values were obtained 5.35, 3.30 % for dasatinib and erlotinib, respectively.

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.

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.

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.

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.

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.

[Treatment status of tyrosine kinase inhibitor for newly-diagnosed chronic myeloid leukemia: a domestic multi-centre retrospective real-world study].

Objective: To retrospectively analyze the treatment status of tyrosine kinase inhibitors (TKI) in newly diagnosed patients with chronic myeloid leukemia (CML) in China. Methods: Data of chronic phase (CP) and accelerated phase (AP) CML patients diagnosed from January 2006 to December 2022 from 77 centers, ≥18 years old, and receiving initial imatinib, nilotinib, dasatinib or flumatinib-therapy within 6 months after diagnosis in China with complete data were retrospectively interrogated. The choice of initial TKI, current TKI medications, treatment switch and reasons, treatment responses and outcomes as well as the variables associated with them were analyzed. Results: 6 893 patients in CP (n=6 453, 93.6%) or AP (n=440, 6.4%) receiving initial imatinib (n=4 906, 71.2%), nilotinib (n=1 157, 16.8%), dasatinib (n=298, 4.3%) or flumatinib (n=532, 7.2%) -therapy. With the median follow-up of 43 (IQR 22-75) months, 1 581 (22.9%) patients switched TKI due to resistance (n=1 055, 15.3%), intolerance (n=248, 3.6%), pursuit of better efficacy (n=168, 2.4%), economic or other reasons (n=110, 1.6%). The frequency of switching TKI in AP patients was significantly-higher than that in CP patients (44.1% vs 21.5%, P<0.001), and more AP patients switched TKI due to resistance than CP patients (75.3% vs 66.1%, P=0.011). Multi-variable analyses showed that male, lower HGB concentration and ELTS intermediate/high-risk cohort were associated with lower cytogenetic and molecular responses rate and poor outcomes in CP patients; higher WBC count and initial the second-generation TKI treatment, the higher response rates; Ph(+) ACA at diagnosis, poor PFS. However, Sokal intermediate/high-risk cohort was only significantly-associated with lower CCyR and MMR rates and the poor PFS. Lower HGB concentration and larger spleen size were significantly-associated with the lower cytogenetic and molecular response rates in AP patients; initial the second-generation TKI treatment, the higher treatment response rates; lower PLT count, higher blasts and Ph(+) ACA, poorer TFS; Ph(+) ACA, poorer OS. Conclusion: At present, the vast majority of newly-diagnosed CML-CP or AP patients could benefit from TKI treatment in the long term with the good treatment responses and survival outcomes.

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.

Senolytics ameliorate the failure of bone regeneration through the cell senescence-related inflammatory signalling pathway.

Stress-induced premature senescent (SIPS) cells induced by various stresses deteriorate cell functions. Dasatinib and quercetin senolytics (DQ) can alleviate several diseases by eliminating senescent cells. α-tricalcium phosphate (α-TCP) is a widely used therapeutic approach for bone restoration but induces bone formation for a comparatively long time. Furthermore, bone infection exacerbates the detrimental prognosis of bone formation during material implant surgery due to oral cavity bacteria and unintentional contamination. It is essential to mitigate the inhibitory effects on bone formation during surgical procedures. Little is known that DQ improves bone formation in Lipopolysaccharide (LPS)-contaminated implants and its intrinsic mechanisms in the study of maxillofacial bone defects. This study aims to investigate whether the administration of DQ ameliorates the impairments on bone repair inflammation and contamination by eliminating SIPS cells. α-TCP and LPS-contaminated α-TCP were implanted into Sprague-Dawley rat calvaria bone defects. Simultaneously, bone formation in the bone defects was investigated with or without the oral administration of DQ. Micro-computed tomography and hematoxylin-eosin staining showed that senolytics significantly enhanced bone formation at the defect site. Histology and immunofluorescence staining revealed that the levels of p21- and p16-positive senescent cells, inflammation, macrophages, reactive oxygen species, and tartrate-resistant acid phosphatase-positive cells declined after administering DQ. DQ could partially alleviate the production of senescent markers and senescence-associated secretory phenotypes in vitro. This study indicates that LPS-contaminated α-TCP-based biomaterials can induce cellular senescence and hamper bone regeneration. Senolytics have significant therapeutic potential in reducing the adverse osteogenic effects of biomaterial-related infections and improving bone formation capacity.

Development of combination therapies with BTK inhibitors and dasatinib to treat CNS-infiltrating E2A-PBX1+/preBCR+ ALL.

ABSTRACT: The t(1;19) translocation, encoding the oncogenic fusion protein E2A (TCF3)-PBX1, is involved in acute lymphoblastic leukemia (ALL) and associated with a pre-B-cell receptor (preBCR+) phenotype. Relapse in patients with E2A-PBX1+ ALL frequently occurs in the central nervous system (CNS). Therefore, there is a medical need for the identification of CNS active regimens for the treatment of E2A-PBX1+/preBCR+ ALL. Using unbiased short hairpin RNA (shRNA) library screening approaches, we identified Bruton tyrosine kinase (BTK) as a key gene involved in both proliferation and dasatinib sensitivity of E2A-PBX1+/preBCR+ ALL. Depletion of BTK by shRNAs resulted in decreased proliferation of dasatinib-treated E2A-PBX1+/preBCR+ cells compared with control-transduced cells. Moreover, the combination of dasatinib with BTK inhibitors (BTKi; ibrutinib, acalabrutinib, or zanubrutinib) significantly decreased E2A-PBX1+/preBCR+ human and murine cell proliferation, reduced phospholipase C gamma 2 (PLCG2) and BTK phosphorylation and total protein levels and increased disease-free survival of mice in secondary transplantation assays, particularly reducing CNS-leukemic infiltration. Hence, dasatinib with ibrutinib reduced pPLCG2 and pBTK in primary ALL patient samples, including E2A-PBX1+ ALLs. In summary, genetic depletion and pharmacological inhibition of BTK increase dasatinib effects in human and mouse with E2A-PBX1+/preBCR+ ALL across most of performed assays, with the combination of dasatinib and BTKi proving effective in reducing CNS infiltration of E2A-PBX1+/preBCR+ ALL cells in vivo.

Interaction of the chemotherapeutic agent oxaliplatin and the tyrosine kinase inhibitor dasatinib with the organic cation transporter 2.

Oxaliplatin (OHP) is effective in colorectal cancer treatment but induces peripheral neurotoxicity (OHP-induced peripheral neurotoxicity, OIPN), diminishing survivor quality of life. Organic cation transporter 2 (OCT2) is a key OHP uptake pathway in dorsal root ganglia. Competing for OCT2-mediated OHP uptake, such as with the tyrosine kinase inhibitor dasatinib, may mitigate OHP side effects. We investigated OHP and dasatinib interaction with OCT2 in human embryonic kidney 293 (HEK293) cells expressing OCT2 within a 10-3 to 10-7 M concentration range. Uptake competition experiments using fluorescent organic cation 4-(4-dimethylaminostyryl)-N-methylpyridinium (ASP+, 1 µM) and mass spectrometry (MS) to determine cellular platinum content indicated that OHP (100 µM) is an OCT2 substrate, mediating OHP cellular toxicity. ASP+ and MS analysis revealed dasatinib as a non-transported inhibitor of hOCT2 (IC50 = 5.9 µM) and as a regulator of OCT2 activity. Dasatinib reduced transporter Vmax, potentially via Y544 phosphorylation suppression. MS analysis showed cellular dasatinib accumulation independent of hOCT2. Although 3 µM dasatinib reduced 100 µM OHP accumulation in hOCT2-HEK293 cells, co-incubation with dasatinib and OHP did not prevent OHP toxicity, possibly due to dasatinib-induced cell viability reduction. In summary, this study demonstrates OHP as an OCT2 substrate and dasatinib as a non-transported inhibitor and regulator of OCT2, offering potential for OIPN mitigation.

Frontline combination of dasatinib and low-intensity chemotherapy in adults with de novo Philadelphia chromosome-positive acute lymphoblastic leukemia.

BACKGROUND: Studies on dasatinib-based low-intensity induction regimens and post-remission strategies are limited in China. Therefore, we conducted a single-center phase 2 trial in newly diagnosed adult patients with Philadelphia chromosome-positive (Ph+) acute lymphoblastic leukemia (ALL) to establish the efficacy and safety of this treatment approach. RESEARCH DESIGN AND METHODS: Patients received one month of dasatinib plus low-intensity chemotherapy and two months of dasatinib monotherapy for induction, followed by a single course of high-dose methotrexate for consolidation. Subsequently, they underwent allogeneic hematopoietic stem cell transplantation (allo-HSCT) or tyrosine kinase inhibitor (TKI)-based treatment for maintenance therapy between October 2015 and August 2022. RESULTS: Twenty-two patients were enrolled. Median age was 45 years (range, 20-71). The rates of major and complete molecular responses in the third month were 18.2% and 40.9% respectively. With a median follow-up of 15 months (range, 5-89), the estimated 3-year disease-free survival (DFS) and overall survival (OS) were 52.4% and 73.2%, respectively. The TKI-based cohort had a significantly poorer DFS (p = 0.014) and OS (p = 0.008) than the allo-HSCT cohort. CONCLUSIONS: Our results suggest that dasatinib-based low-intensity chemotherapy is safe and effective as an induction strategy in the Chinese population. Allo-HSCT plays a crucial role in the long-term outcomes of patients with Ph+ ALL. CLINICAL TRIAL REGISTRATION: The trial was registered at ClinicalTrials.gov as NCT02690922.

[The Effect and Safety of Flumatinib in Patients with Chronic Myelogenous Leukemia Failed First-and Second-line Treatment].

OBJECTIVE: To analyze the efficacy and safety of flumatinib, a second-generation tyrosine kinase inhibitor (TKI) independently developed in China, in patients with chronic myelogenous leukemia in chronic phase (CML-CP) who falied first-line and second-line treatment. METHODS: The clinical data of 30 CML-CP patients treated with flumatinib in Lianyungang First People's Hospital from January 2020 to September 2022 were collected retrospectively. Among them, 15 patients who received imatinib first-line treatment but failed treatment were included in the second-line group, and the other 15 patients who failed second-line treatment with nilotinib or dasatinib were included in the third-line group. The hematological and molecular responses of the patients in the two groups at 3, 6 and 12 months of treatment, and the event-free survival (EFS) and adverse reactions of patients at the end of follow-up were statistical analyzed. RESULTS: At 3, 6, and 12 months of treatment, 10, 11, and 12 patients in the second line group achieved major molecular response (MMR), which was higher than that of 3, 4, and 5 patients in the third line group (P =0.010, P =0.011, P =0.010). At 3 months of treatment, 12 and 13 patients achieved complete hematological response (CHR) and early molecular response (EMR) in the second-line group, which was higher than that of 9 and 13 patients in the third-line group, but the difference between the two groups was not statistically significant (P =0.232, P =1.000); At 6 and 12 months of treatment, 6 and 7 patients in the second-line group achieved MR4.5, which were higher than of 3 and 2 cases in the third-line group, but the difference was not statistically significant (P =0.427, P =0.713). The hematological adverse reactions of patients in the second-line group during treatment the period were mainly grade 1-2 thrombocytopenia and anemia, and no grade 3-4 of adverse reactions occurred. In the third-line group, there were 2 cases of grade 1-2 thrombocytopenia, grade 1-2 anemia and white blood cell 3 cases were reduced each, 1 case of grade 3-4 anemia, 2 cases of grade 3-4 neutropenia. The non-hematological adverse reactions in the second-line group were rash (2 cases), headache (1 case), diarrhea (1 case), fatigue (1 case), limb pain (1 case). There were 1 cases of diarrhea, 1 cases of nausea, and 1 cases of edema in the third-line group. There was no statistical significance in hematological and non-hematological adverse reactions between the two groups of patients (P >0.05). At the end of follow-up, the EFS rate of patients in the second-line group was higher than that in the third-line group (100% vs 93.3%), but the difference was not statistically significant (P =0.317). CONCLUSION: The second-generation TKI flumatinib independently developed in China, has good curative effect and safety for CML-CP patients who failed first-line and second-line treatment.

[Discontinuation of tyrosine kinase inhibitors before epiphyseal closure leading to improved short stature in pediatric chronic myelogenous leukemia].

A 3-year-old boy was referred to our hospital with splenomegaly. Blood tests revealed hyperleukocytosis and bone marrow examination showed major BCR::ABL1 fusion, leading to the diagnosis of chronic myelogenous leukemia (CML). Due to intolerance, the tyrosine kinase inhibitor (TKI) was changed from imatinib to dasatinib to nilotinib. The patient achieved molecular remission but became markedly short in stature, measuring 129.3 cm (height standard deviation score [SDS] -3.3) at the age of 12. TKI therapy was discontinued at age 12 years and 10 months, which was 9 years and 8 months after the start of TKI and 1 year and 6 months after achievement of MR4.0, as discontinuation before epiphyseal closure would not improve short stature. At 2 years and 6 months after discontinuation, the patient's height improved to 156.1 cm (SDS-2.0) without relapse. Growth suppression by TKIs is a problem in the management of pediatric CML. This case illustrates how improvement in severe short stature can be achieved by discontinuing TKI therapy before epiphyseal closure.

Cellular senescence of granulosa cells in the pathogenesis of polycystic ovary syndrome.

Polycystic ovary syndrome (PCOS) is one of the most common endocrine disorders in women of reproductive age, but its pathology has not been fully characterized and the optimal treatment strategy remains unclear. Cellular senescence is a permanent state of cell-cycle arrest that can be induced by multiple stresses. Senescent cells contribute to the pathogenesis of various diseases, owing to an alteration in secretory profile, termed 'senescence-associated secretory phenotype' (SASP), including with respect to pro-inflammatory cytokines. Senolytics, a class of drugs that selectively eliminate senescent cells, are now being used clinically, and a combination of dasatinib and quercetin (DQ) has been extensively used as a senolytic. We aimed to investigate whether cellular senescence is involved in the pathology of PCOS and whether DQ treatment has beneficial effects in patients with PCOS. We obtained ovaries from patients with or without PCOS, and established a mouse model of PCOS by injecting dehydroepiandrosterone. The expression of the senescence markers p16INK4a, p21, p53, γH2AX, and senescence-associated ß-galactosidase and the SASP-related factor interleukin-6 was significantly higher in the ovaries of patients with PCOS and PCOS mice than in controls. To evaluate the effects of hyperandrogenism and DQ on cellular senescence in vitro, we stimulated cultured human granulosa cells (GCs) with testosterone and treated them with DQ. The expression of markers of senescence and a SASP-related factor was increased by testosterone, and DQ reduced this increase. DQ reduced the expression of markers of senescence and a SASP-related factor in the ovaries of PCOS mice and improved their morphology. These results indicate that cellular senescence occurs in PCOS. Hyperandrogenism causes cellular senescence in GCs in PCOS, and senolytic treatment reduces the accumulation of senescent GCs and improves ovarian morphology under hyperandrogenism. Thus, DQ might represent a novel therapy for PCOS.

Enhancement of NETosis by ACE2-cross-reactive anti-SARS-CoV-2 RBD antibodies in patients with COVID-19.

BACKGROUND: High levels of neutrophil extracellular trap (NET) formation or NETosis and autoantibodies are related to poor prognosis and disease severity of COVID-19 patients. Human angiotensin-converting enzyme 2 (ACE2) cross-reactive anti-severe acute respiratory syndrome coronavirus 2 spike protein receptor-binding domain (SARS-CoV-2 RBD) antibodies (CR Abs) have been reported as one of the sources of anti-ACE2 autoantibodies. However, the pathological implications of CR Abs in NET formation remain unknown. METHODS: In this study, we first assessed the presence of CR Abs in the sera of COVID-19 patients with different severity by serological analysis. Sera and purified IgG from CR Abs positive COVID-19 patients as well as a mouse monoclonal Ab (mAb 127) that can recognize both ACE2 and the RBD were tested for their influence on NETosis and the possible mechanisms involved were studied. RESULTS: An association between CR Abs levels and the severity of COVID-19 in 120 patients was found. The CR Abs-positive sera and IgG from severe COVID-19 patients and mAb 127 significantly activated human leukocytes and triggered NETosis, in the presence of RBD. This NETosis, triggered by the coexistence of CR Abs and RBD, activated thrombus-related cells but was abolished when the interaction between CR Abs and ACE2 or Fc receptors was disrupted. We also revealed that CR Abs-induced NETosis was suppressed in the presence of recombinant ACE2 or the Src family kinase inhibitor, dasatinib. Furthermore, we found that COVID-19 vaccination not only reduced COVID-19 severity but also prevented the production of CR Abs after SARS-CoV-2 infection. CONCLUSIONS: Our findings provide possible pathogenic effects of CR Abs in exacerbating COVID-19 by enhancing NETosis, highlighting ACE2 and dasatinib as potential treatments, and supporting the benefit of vaccination in reducing disease severity and CR Abs production in COVID-19 patients.

The Differential Effect of Senolytics on SASP Cytokine Secretion and Regulation of EMT by CAFs.

The tumor microenvironment (TME) plays an essential role in tumor progression and in modulating tumor response to anticancer therapy. Cellular senescence leads to a switch in the cell secretome, characterized by the senescence-associated secretory phenotype (SASP), which may regulate tumorigenesis. Senolytic therapy is considered a novel anticancer strategy that eliminates the deleterious effects of senescent cells in the TME. Here, we show that two different types of senolytic drugs, despite efficiently depleting senescent cells, have opposite effects on cancer-associated fibroblasts (CAFs) and their ability to regulate epithelial-mesenchymal transition (EMT). We found that senolytic drugs, navitoclax and the combination of dasatinib/quercetin, reduced the number of spontaneously senescent and TNF-induced senescent CAFs. Despite the depletion of senescent cells, the combination of dasatinib/quercetin versus navitoclax increased the secretion of the SASP pro-inflammatory cytokine IL-6. This differential effect correlated with the promotion of enhanced migration and EMT in MC38 colorectal cancer cells. Our results demonstrate that some senolytics may have side effects unrelated to their senolytic activity and may promote tumorigenesis. We argue for more careful and extensive studies of the effects of senolytics on various aspects of tumor progression and tumor resistance to therapy before the senolytic strategy is implemented in the clinic.

An electrochemical sensor based on carbon nanofiber and molecular imprinting strategy for dasatinib recognition.

Herein, we proposed a new approach to design a MIP-based electrochemical sensor with carbon nanofiber (CNF), which could improve its conductivities as well as electrode sensitivity and successful detection of dasatinib (DAS). CNFs are capable of forming high porosity with significant interconnected porous networks. The poly(2-hydroxyethyl-methacrylate-N-methacryloyl-L-tyrosine) (PHEMA-MATyr) copolymer was synthesized in the presence of both CNF and DAS by photopolymerization. After optimization of the parameters, the modified MIP-based electrochemical sensor demonstrated the ability to determine the DAS in the linear working range of 1.0 × 10-14-1.0 × 10-13 M for the standard solution and commercial serum samples with a LOD of 1.76 × 10-15 and 2.46 × 10-15, respectively. Good linearity for DAS was observed with correlation coefficients (r) of 0.996 and 0.997 for the standard solution and commercial serum samples, respectively. The recoveries of the DAS ranged from 99.45 % to 99.53 % for the tablet dosage form and commercial serum samples, with average relative standard deviations below 1.96 % in both cases. The proposed modified sensor demonstrated significant sensitivity and selectivity for the rapid determination of DAS in commercial serum samples and tablet form.