A review on potential heterocycles for the treatment of glioblastoma targeting receptor tyrosine kinases

Glioblastoma,the most aggressive form of brain tumor,poses significant challenges in terms of treatment success and patient survival.Current treatment modalities for glioblastoma include radiation therapy,surgical intervention,and chemotherapy.Unfortunately,the median survival rate remains dishearteningly low at 12–15 months.One of the major obstacles in treating glioblastoma is the recurrence of tumors,making chemotherapy the primary approach for secondary glioma patients.However,the efficacy of drugs is hampered by the presence of the blood-brain barrier and multidrug resistance mechanisms.Consequently,considerable research efforts have been directed toward understanding the underlying signaling pathways involved in glioma and developing targeted drugs.To tackle glioma,numerous studies have examined kinase-downstream signaling pathways such as RAS-RAF-MEKERK-MPAK.By targeting specific signaling pathways,heterocyclic compounds have demonstrated efficacy in glioma therapeutics.Additionally,key kinases including phosphatidylinositol 3-kinase(PI3K),serine/threonine kinase,cytoplasmic tyrosine kinase(CTK),receptor tyrosine kinase(RTK)and lipid kinase(LK)have been considered for investigation.These pathways play crucial roles in drug effectiveness in glioma treatment.Heterocyclic compounds,encompassing pyrimidine,thiazole,quinazoline,imidazole,indole,acridone,triazine,and other derivatives,have shown promising results in targeting these pathways.As part of this review,we propose exploring novel structures with low toxicity and high potency for glioma treatment.The development of these compounds should strive to overcome multidrug resistance mechanisms and efficiently penetrate the blood-brain barrier.By optimizing the chemical properties and designing compounds with enhanced drug-like characteristics,we can maximize their therapeutic value and minimize adverse effects.Considering the complex nature of glioblastoma,these novel structures should be rigorously tested and evaluated for their efficacy and safety profiles.

Advances in MET tyrosine kinase inhibitors in gastric cancer

Gastric cancer is among the most frequently occurring cancers and a leading cause of cancer-related deaths globally.Because gastric cancer is highly heterogenous and comprised of different subtypes with distinct molecular and clinical characteristics,the management of gastric cancer calls for better-defined,biomarker-guided,molecular-based treatment strategies.MET is a receptor tyrosine kinase mediating important physiologic processes,such as embryogenesis,tissue regeneration,and wound healing.However,mounting evidence suggests that aberrant MET pathway activation contributes to tumour proliferation and metastasis in multiple cancer types,including gastric cancer,and is associated with poor patient outcomes.As such,MET-targeting therapies are being actively developed and promising progress has been demonstrated,especially with MET tyrosine kinase inhibitors.This review aims to briefly introduce the role of MET alterations in gastric cancer and summarize in detail the current progress of MET tyrosine kinase inhibitors in this disease area with a focus on savolitinib,tepotinib,capmatinib,and crizotinib.Building on current knowledge,this review further discusses existing challenges in MET alterations testing,possible resistance mechanisms to MET inhibitors,and future directions of MET-targeting therapies.

Risk of hepatitis B virus reactivation in oncological patients treated with tyrosine kinase inhibitors:A case report and literature analysis

Hepatitis B virus(HBV)reactivation(HBVr)represents a severe and potentially life-threatening condition,and preventive measures are available through blood test screening or prophylactic therapy administration.The assessment of HBVr traditionally considers factors such as HBV profile,including hepatitis B surface antigen(HBsAg)and antibody to hepatitis B core antigen,along with type of medication(chemotherapy;immunomodulants).Nevertheless,consideration of possible patient’s underlying tumor and the specific malignancy type(solid or hematologic)plays a crucial role and needs to be assessed for decision-making process.

Diabetes and high-glucose could upregulate the expression of receptor for activated C kinase 1 in retina

BACKGROUND Diabetic retinopathy(DR)is a major ocular complication of diabetes mellitus,leading to visual impairment.Retinal pigment epithelium(RPE)injury is a key component of the outer blood retinal barrier,and its damage is an important indicator of DR.Receptor for activated C kinase 1(RACK1)activates protein kinase C-ε(PKC-ε)to promote the generation of reactive oxygen species(ROS)in RPE cells,leading to apoptosis.Therefore,we hypothesize that the activation of RACK1 under hypoxic/high-glucose conditions may promote RPE cell apoptosis by modulating PKC-ε/ROS,thereby disrupting the barrier effect of the outer blood retinal barrier and contributing to the progression of DR.AIM To investigate the role and associated underlying mechanisms of RACK1 in the development of early DR.METHODS In this study,Sprague-Dawley rats and adult RPE cell line-19(ARPE-19)cells were used as in vivo and in vitro models,respectively,to explore the role of RACK1 in mediating PKC-εin early DR.Furthermore,the impact of RACK1 on apoptosis and barrier function of RPE cells was also investigated in the former model.RESULTS Streptozotocin-induced diabetic rats showed increased apoptosis and upregulated expression of RACK1 and PKC-εproteins in RPE cells following a prolonged modeling.Similarly,ARPE-19 cells exposed to high glucose and hypoxia displayed elevated mRNA and protein levels of RACK1 and PKC-ε,accompanied by an increases in ROS production,apoptosis rate,and monolayer permeability.However,silencing RACK1 significantly downregulated the expression of PKC-εand ROS,reduced cell apoptosis and permeability,and protected barrier function.CONCLUSION RACK1 plays a significant role in the development of early DR and might serve as a potential therapeutic target for DR by regulating RPE apoptosis and barrier function.

Detection of LAMA2 c.715C>G:p.R239G mutation in a newborn with raised creatine kinase: A case report

BACKGROUND We report a rare case of primary clinical presentation featuring elevated creatine kinase(CK)levels in a neonate,which is associated with the LAMA2 gene.In this case,a heterozygous mutation in exon5 of the LAMA2 gene,c.715C>G(resulting in a change of nucleotide number 715 in the coding region from cytosine to gua-nine),induced an amino acid alteration p.R239G(No.239)in the patient,repre-senting a missense mutation.This observation may be elucidated by the neonatal creatine monitoring mechanism,a phenomenon not previously reported.CASE SUMMARY We analysed the case of a neonate presenting solely with elevated CK levels who was eventually discharged after supportive treatment.The chief complaint was identification of increased CK levels for 15 d and higher CK values for 1 d.Ad-mission occurred at 18 d of age,and despite prolonged treatment with creatine and vitamin C,the elevated CK levels showed limited improvement.Whole exo-me sequencing revealed the presence of a c.715C>G mutation in LAMA2 in the newborn,correlating with a clinical phenotype.However,the available informa-tion offers insufficient evidence for clinical pathogenicity.CONCLUSION Mutations in LAMA2 are associated with the clinical phenotype of increased neonatal CK levels,for which no specific treatment exists.Whole genome sequen-cing facilitates early diagnosis.

Wheat kinase TaSnRK2.4 forms a functional module with phosphatase TaPP2C01 and transcription factor TaABF2 to regulate drought response

SNF1-related protein kinase 2(SnRK2)family members are essential components of the plant abscisic acid(ABA)signaling pathway initiated by osmotic stress and triggering a drought stress response.This study characterized the molecular properties of TaSnRK2.4 and its function in mediating adaptation to drought in Triticum aestivum.Transcripts of TaSnRK2.4 were upregulated upon drought and ABA signaling and associated with drought-and ABA-responsive cis-elements ABRE and DRE,and MYB and MYC binding sites in the promoter as indicated by reporter GUS protein staining and activity driven by truncations of the promoter.Yeast two-hybrid,BiFC,and Co-IP assays indicated that TaSnRK2.4 protein interacts with TaPP2C01 and an ABF transcription factor(TF)TaABF2.The results suggested that TaSnRK2.4 forms a functional TaPP2C01-TaSnRK2.4-TaABF2 module with its upstream and downstream partners.Transgene analysis revealed that TaSnRK2.4 and TaABF2 positively regulate drought tolerance whereas TaPP2C01 acts negatively by modulating stomatal movement,osmotic adjustment,reactive oxygen species(ROS)homeostasis,and root morphology.Expression analysis,yeast one-hybrid,and transcriptional activation assays indicated that several osmotic stress-responsive genes,including TaSLAC1-4,TaP5CS3,TaSOD5,TaCAT1,and TaPIN4,are regulated by TaABF2.Transgene analysis verified their functions in positively regulating stomatal movement(TaSLAC1-4),proline accumulation(TaP5CS3),SOD activity(TaSOD5),CAT activity(TaCAT1),and root morphology(TaPIN4).There were high correlations between plant biomass and yield with module transcripts in a wheat variety panel cultivated under drought conditions in the field.Our findings provide insights into understanding plant drought response underlying the SnRK2 signaling pathway in common wheat.

Vaccinia-related kinase 2 variants differentially affect breast cancer growth by regulating kinase activity

Genetic information is transcribed from genomic DNA to mRNA,which is then translated into threedimensional proteins.mRNAs can undergo various post-transcriptional modifications,including RNA editing that alters mRNA sequences,ultimately affecting protein function.In this study,RNA editing was identified at the 499th base(c.499)of human vaccinia-related kinase 2(VRK2).This RNA editing changes the amino acid in the catalytic domain of VRK2 from isoleucine(with adenine base)to valine(with guanine base).Isoleucine-containing VRK2 has higher kinase activity than the valine-containing VRK2,which leads to an increase in tumor cell proliferation.Earlier we reported that VRK2 directly interacts with dystrobrevin-binding protein(dysbindin)and results in reducing its stability.Herein,we demonstrate that isoleucine-containing VRK2 decreases the level of dysbindin than valinecontaining VRK2.Dysbindin interacts with cyclin D and thereby regulates its expression and function.The reduction in the level of dysbindin by isoleucine-containing VRK2 further enhances the cyclin D expression,resulting in increased tumor growth and reduction in survival rates.It has also been observed that in patient samples,VRK2 level was elevated in breast cancer tissue compared to normal breast tissue.Additionally,the isoleucine form of VRK2 exhibited a greater increase in breast cancer tissue.Therefore,it is concluded that VRK2,especially dependent on the 167th variant amino acid,can be one of the indexes of tumor progression and proliferation.

Navigating treatment resistance:Janus kinase inhibitors for ulcerative colitis

The management of refractory ulcerative colitis(UC)and acute severe UC(ASUC)is challenging due to the lack of standardized approaches in cases resistant to multiple treatments.In this editorial,I investigate the efficacy and safety of Janus kinase inhibitors,particularly upadacitinib and tofacitinib,in controlling severe and refractory disease.I highlight a notable case report by Xu et al,which explores the case of a patient with primary nonresponse to two classes of biologics and two fecal microbiota transplants who exhibited a remarkable response to upadacitinib.Furthermore,I discuss the use of tofacitinib in refractory UC and ASUC,either as monotherapy or in combination with biologics,which has shown promising response rates.Additionally,emerging evidence of upadacitinib efficacy in ASUC is presented.Overall,these cases emphasize the complex nature of managing refractory ASUC and the potential of small-molecule therapies to achieve remission.Further research is needed to refine treatment strategies for patients with treatment-resistant UC.

Loss of monopolar spindle-binding protein 3B expression promotes colorectal cancer malignant behaviors by activation of target of rapamycin kinase/autophagy signaling

BACKGROUND Monopolar spindle-binding protein 3B(MOB3B)functions as a signal transducer and altered MOB3B expression is associated with the development of human cancers.AIM To investigate the role of MOB3B in colorectal cancer(CRC).METHODS This study collected 102 CRC tissue samples for immunohistochemical detection of MOB3B expression for association with CRC prognosis.After overexpression and knockdown of MOB3B expression were induced in CRC cell lines,changes in cell viability,migration,invasion,and gene expression were assayed.Tumor cell autophagy was detected using transmission electron microscopy,while nude mouse xenograft experiments were performed to confirm the in-vitro results.RESULTS MOB3B expression was reduced in CRC vs normal tissues and loss of MOB3B expression was associated with poor CRC prognosis.Overexpression of MOB3B protein in vitro attenuated the cell viability as well as the migration and invasion capacities of CRC cells,whereas knockdown of MOB3B expression had the opposite effects in CRC cells.At the molecular level,microtubule-associated protein light chain 3 II/I expression was elevated,whereas the expression of matrix metalloproteinase(MMP)2,MMP9,sequestosome 1,and phosphorylated mechanistic target of rapamycin kinase(mTOR)was downregulated in MOB3B-overexpressing RKO cells.In contrast,the opposite results were observed in tumor cells with MOB3B knockdown.The nude mouse data confirmed these in-vitro findings,i.e.,MOB3B expression suppressed CRC cell xenograft growth,whereas knockdown of MOB3B expression promoted the growth of CRC cell xenografts.CONCLUSION Loss of MOB3B expression promotes CRC development and malignant behaviors,suggesting a potential tumor suppressive role of MOB3B in CRC by inhibition of mTOR/autophagy signaling.

Navigating the complex terrain of hepatitis B virus reactivation in the era of Bruton tyrosine kinase inhibitors

In this editorial,we offer a summary of the risk associated with hepatitis B reactivation(HBVr)in the setting of both solid and hematologic malignancies treated with Bruton tyrosine kinase(BTK)inhibitors,with insights derived from current studies.Furthermore,we emphasize the critical need for a framework regarding robust risk evaluation in patients undergoing such treatments.This framework is essential for identifying those at increased risk of HBVr,enabling healthcare providers to implement proactive measures to prevent reactivation and ensure the safe administration of BTK inhibitor therapy.

Primary anaplastic lymphoma kinase-positive large B-cell lymphoma of the left bulbar conjunctiva: A case report

BACKGROUND Anaplastic lymphoma kinase(ALK)-positive large B-cell lymphoma(LBCL)is an aggressive and rare variant of diffuse LBCL.Herein,we report an uncommon case of stage IE extranodal ALK-positive LBCL initially originating in the bulbar con-junctiva.CASE SUMMARY A 63-year-old woman presented with a mass in the left bulbar conjunctiva that had persisted for six months,accompanied by swelling and pain that had per-sisted for 3 d.Eye examination revealed an 8 mm slightly elevated pink mass in the lower conjunctival sac of the left eye.Microscopically,the tumor was com-posed of large immunoblastic and plasmablastic large lymphoid cells with scattered anaplastic or multinucleated large cells.Immunophenotypically,the neoplastic cells were positive for ALK,CD10,CD138,Kappa,MUM1,BOB.1,OCT-2,CD4,CD45,EMA,CD79a,CD38,and AE1/AE3,and negative for CD20,PAX5,Lambda,BCL6,CD30 and all other T-cell antigens.The results of gene rearrangement tests showed monoclonal IGH/IGK/IGL and TCRD rearran-gements.Fluorescence in situ hybridization studies did not reveal any BCL2,BCL6 or MYC rearrangements.Furthermore,Epstein-Barr virus was not detected by in situ hybridization in the lesions.Based on the histopathological and imaging examinations,the neoplasm was classified as stage IE ALK-positive LBCL.No further treatments were administered.At the 6,15,and 21 mo postoperative follow-up visits,the patient was in good condition,without obvious discomfort.This case represents the first example of primary extranodal ALK-positive LBCL presenting as a bulbar conjunctival mass,which is extremely rare and shares morphological and immunohistochemical features with a variety of other neo-plasms that can result in misdiagnosis.CONCLUSION Awareness of the condition presented in this case report is necessary for early and accurate diagnosis and appropriate treatment.

Bibliometric analysis of phosphoglycerate kinase 1 expression in breast cancer and its distinct upregulation in triple-negative breast cancer

BACKGROUND Phosphoglycerate kinase 1(PGK1)has been identified as a possible biomarker for breast cancer(BC)and may play a role in the development and advancement of triple-negative BC(TNBC).AIM To explore the PGK1 and BC research status and PGK1 expression and mecha-nism differences among TNBC,non-TNBC,and normal breast tissue.METHODS PGK1 and BC related literature was downloaded from Web of Science Core Co-llection Core Collection.Publication counts,key-word frequency,cooperation networks,and theme trends were analyzed.Normal breast,TNBC,and non-TNBC mRNA data were gathered,and differentially expressed genes obtained.Area under the summary receiver operating characteristic curves,sensitivity and specificity of PGK1 expression were determined.Kaplan Meier revealed PGK1’s prognostic implication.PGK1 co-expressed genes were explored,and Gene Onto-logy,Kyoto Encyclopedia of Genes and Genomes,and Disease Ontology applied.Protein-protein interaction networks were constructed.Hub genes identified.RESULTS PGK1 and BC related publications have surged since 2020,with China leading the way.The most frequent keyword was“Expression”.Collaborative networks were found among co-citations,countries,institutions,and authors.PGK1 expression and BC progression were research hotspots,and PGK1 expression and BC survival were research frontiers.In 16 TNBC vs non-cancerous breast and 15 TNBC vs non-TNBC datasets,PGK1 mRNA levels were higher in 1159 TNBC than 1205 non-cancerous breast cases[standardized mean differences(SMD):0.85,95%confidence interval(95%CI):0.54-1.16,I²=86%,P<0.001].PGK1 expression was higher in 1520 TNBC than 7072 non-TNBC cases(SMD:0.25,95%CI:0.03-0.47,I²=91%,P=0.02).Recurrence free survival was lower in PGK1-high-expression than PGK1-low-expression group(hazard ratio:1.282,P=0.023).PGK1 co-expressed genes were concentrated in ATP metabolic process,HIF-1 signaling,and glycolysis/gluconeogenesis pathways.CONCLUSION PGK1 expression is a research hotspot and frontier direction in the BC field.PGK1 may play a strong role in promoting cancer in TNBC by mediating metabolism and HIF-1 signaling pathways.

MicroRNA-298 determines the radio-resistance of colorectal cancer cells by directly targeting human dual-specificity tyrosine(Y)-regulated kinase 1A

BACKGROUND Radiotherapy stands as a promising therapeutic modality for colorectal cancer(CRC);yet,the formidable challenge posed by radio-resistance significantly undermines its efficacy in achieving CRC remission.AIM To elucidate the role played by microRNA-298(miR-298)in CRC radio-resistance.METHODS To establish a radio-resistant CRC cell line,HT-29 cells underwent exposure to 5 gray ionizing radiation that was followed by a 7-d recovery period.The quantification of miR-298 levels within CRC cells was conducted through quantitative RT-PCR,and protein expression determination was realized through Western blotting.Cell viability was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and proliferation by clonogenic assay.Radio-induced apoptosis was discerned through flow cytometry analysis.RESULTS We observed a marked upregulation of miR-298 in radio-resistant CRC cells.MiR-298 emerged as a key determinant of cell survival following radiation exposure,as its overexpression led to a notable reduction in radiation-induced apoptosis.Intriguingly,miR-298 expression exhibited a strong correlation with CRC cell viability.Further investigation unveiled human dual-specificity tyrosine(Y)-regulated kinase 1A(DYRK1A)as miR-298’s direct target.CONCLUSION Taken together,our findings underline the role played by miR-298 in bolstering radio-resistance in CRC cells by means of DYRK1A downregulation,thereby positioning miR-298 as a promising candidate for mitigating radioresistance in CRC.

Advanced Lung Adenocarcinoma with EGFR 19-del Mutation Transformed into SCC after EGFR-tyrosine Kinase inhibitors Treatment:A Case report

BACKGROUND Epidermal growth factor receptor tyrosine kinase inhibitors(EGFR-TKIs)significantly improve the survival of patients with Epidermal growth factor receptor(EGFR)sensitive mutations in non-small cell lung cancer(NSCLC).CASE SUMMARY A 67-year-old female patient in advanced lung adenocarcinoma suffered from drug resistance after EGFR-TKIs treatment.Secondary pathological tissue biopsy confirmed squamous cell carcinoma(SCC)transformation.Patients inevitably encountered drug resistance issues after receiving EGFR-TKIs treatment for a certain period of time,while EGFR-TKIs can significantly improve the survival of patients with EGFR-sensitive mutations in NSCLC.Notably,EGFR-TKIs resistance includes primary and acquired.Pathological transformation is one of the mechanisms of acquired resistance in EGFR-TKIs,with SCC transformation being relatively rare.Our results provide more detailed results of the patient’s diagnosis and treatment process on SCC transformation after EGFR-TKIs treatment for lung adenocarcinoma.CONCLUSION Squamous cell carcinoma transformation is one of the acquired resistance mechanisms of EGFR-TKIs in advanced lung adenocarcinoma with EGFR mutations.

Polo-like kinase 1 as a biomarker predicts the prognosis and immunotherapy of breast invasive carcinoma patients

Invasive breast carcinoma(BRCA)is associated with poor prognosis and high risk of mortality.Therefore,it is critical to identify novel biomarkers for the prognostic assessment of BRCA.Methods:The expression data of polo-like kinase 1(PLK1)in BRCA and the corresponding clinical information were extracted from TCGA and GEO databases.PLK1 expression was validated in diverse breast cancer cell lines by quantitative real-time polymerase chain reaction(qRT-PCR)and western blotting.Single sample gene set enrichment analysis(ssGSEA)was performed to evaluate immune infiltration in the BRCA microenvironment,and the random forest(RF)and support vector machine(SVM)algorithms were used to screen for the hub infiltrating cells and calculate the immunophenoscore(IPS).The RF algorithm and COX regression model were applied to calculate survival risk scores based on the PLK1 expression and immune cell infiltration.Finally,a prognostic nomogram was constructed with the risk score and pathological stage,and its clinical potential was evaluated by plotting calibration charts and DCA curves.The application of the nomogram was further validated in an immunotherapy cohort.Results:PLK1 expression was significantly higher in the tumor samples in TCGA-BRCA cohort.Furthermore,PLK1 expression level,age and stage were identified as independent prognostic factors of BRCA.While the IPS was unaffected by PLK1 expression,the TMB and MATH scores were higher in the PLK1-high group,and the TIDE scores were higher for the PLK1-low patients.We also identified 6 immune cell types with high infiltration,along with 11 immune cell types with low infiltration in the PLK1-high tumors.A risk score was devised using PLK1 expression and hub immune cells,which predicted the prognosis of BRCA patients.In addition,a nomogram was constructed based on the risk score and pathological staging,and showed good predictive performance.Conclusions:PLK1 expression and immune cell infiltration can predict post-immunotherapy prognosis of BRCA patients.

Bruton’s tyrosine kinase inhibitors in primary central nervous system lymphoma:New hopes on the horizon

In this editorial,we comment on the article by Wang et al.This manuscript explores the potential synergistic effects of combining zanubrutinib,a novel oral inhibitor of Bruton’s tyrosine kinase,with high-dose methotrexate(HD-MTX)as a therapeutic intervention for primary central nervous system lymphoma(PCNSL).The study involves a retrospective analysis of 19 PCNSL patients,highlighting clinicopathological characteristics,treatment outcomes,and genomic biomarkers.The results indicate the combination’s good tolerance and strong antitumor activity,with an 84.2%overall response rate.The authors emphasize the potential of zanubrutinib to modulate key genomic features of PCNSL,particularly mutations in myeloid differentiation primary response 88 and cluster of differentiation 79B.Furthermore,the study investigates the role of circulating tumor DNA in cerebrospinal fluid for disease surveillance and treatment response monitoring.In essence,the study provides valuable insights into the potential of combining zanubrutinib with HD-MTX as a frontline therapeutic regimen for PCNSL.The findings underscore the importance of exploring alternative treatment modalities and monitoring genomic and liquid biopsy markers to optimize patient outcomes.While the findings suggest promise,the study’s limitations should be considered,and further research is needed to establish the clinical relevance of this therapeutic approach for PCNSL.

炙马钱子对重症肌无力小鼠血清MMP-3及抗MuSK抗体影响

目的探讨炙马钱子通过调节基质金属蛋白酶3(MMP-3)致使重症肌无力发病机制。方法45只8周雄性C57BL/6J小鼠,麻醉后,随机抽取37只模型组小鼠,共用40μg的肌肉特异性酪氨酸激酶(MuSK)乳化在100μL磷酸盐缓冲溶液(PBS)和100μL完全弗氏佐剂(CFA)腹腔、后脚注射,剩余8只正常组注射100μL PBS和100μL CFA佐剂,并24 h内注射环磷酰胺(300 mg/kg,溶解在0.9%的生理盐水中配置成10 mg/mL的终浓度)抑制免疫抵抗。30 d补充注射1次,通过小鼠体征及行为学等观察确定造模周期。在造模成功当天,将小鼠随机分为正常组、模型组、炙马钱子组、AG490组,每组8只,炙马钱子组予炙马钱子250 mg/(kg·d)连续灌胃30 d;AG490组予炙马钱子250 mg/(kg·d)连续灌胃30 d,AG4905 mg/(kg·d)连续腹腔注射30 d;正常组和模型组灌胃等量0.9%的生理盐水。采用酶联免疫吸附(ELISA)法检测血清MuSK滴度,蛋白质印迹法(Western blot)检测各组神经肌肉接头处中MMP-3的蛋白表达水平。结果MuSK滴度水平:正常组MuSK滴度水平最低(3.23±1.89);与模型组比较,炙马钱子组、AG490组血清MuSK滴度显著降低[(242.12±24.69)、(133.68±27.27)比(856.93±32.44),P<0.05],且随着给药时间的延长,炙马钱子组、AG490组MuSK滴度水平逐渐下降。MMP-3的蛋白表达水平:正常组MMP-3的蛋白表达水平最低(1.00±0.07);与模型组比较,炙马钱子组、AG490组MMP-3的蛋白表达水平逐渐下降[(1.60±0.10)、(1.27±0.13)比(2.30±0.11),P<0.05]。结论炙马钱子可能通过使MMP-3合成减少,降低MuSK抗体,达到治疗重症肌无力的作用。

Genome-wide identification of the mitogen-activated protein kinase kinases in pear and their functional analysis in response to black spot

The mitogen-activated protein kinase(MAPK)cascade is crucial to plant growth,development,and stress responses.MAPK kinases(MAPKK)play a vital role in linking upstream MAPKK kinases(MAPKKK)with the downstream MAPK.Black spot is one of the most serious fungal diseases of pear which is an important part of the fruit industry in China.The MAPKK genes have been identified in many plants,however,none has been reported in pear(Pyrus bretschneideri).In order to explore whether MAPK gene of pear is related to black spot disease,we designed this experiment.The present study investigated eight putative PbrMAPKK genes obtained from the Chinese white pear genome.The phylogenetic analysis revealed that PbrMAPKK genes were divided into A,B,C,and D groups.These PbrMAPKK genes are randomly distributed on 7 out of 17 chromosomes and mainly originated from the whole-genome duplication(WGD)event.The expression analysis of PbrMAPKK genes in seven pear tissues and the leaves of susceptible and resistant varieties after Alternaria alternata infection by quantitative real-time PCR(qRT-PCR)identified seven candidate genes associated with resistance.Furthermore,virus-induced gene silencing(VIGS)indicated that PbrMAPKK6 gene enhanced resistance to pear black spot disease in pear.

c-Abl kinase at the crossroads of healthy synaptic remodeling and synaptic dysfunction in neurodegenerative diseases

Our ability to learn and remember depends on the active formation,remodeling,and elimination of synapses.Thus,the development and growth of synapses as well as their weakening and elimination are essential for neuronal rewiring.The structural reorganization of synaptic complexes,changes in actin cytos keleton and organelle dynamics,as well as modulation of gene expression,determine synaptic plasticity.It has been proposed that dys regulation of these key synaptic homeostatic processes underlies the synaptic dysfunction observed in many neurodegenerative diseases.Much is known about downstream signaling of activated N-methyl-D-aspartate andα-amino-3-hydroxy-5-methyl-4-isoazolepro pionate receptors;howeve r,other signaling pathways can also contribute to synaptic plasticity and long-lasting changes in learning and memory.The non-receptor tyrosine kinase c-Abl(ABL1)is a key signal transducer of intra and extracellular signals,and it shuttles between the cyto plasm and the nucleus.This review focuses on c-Abl and its synaptic and neuronal functions.Here,we discuss the evidence showing that the activation of c-Abl can be detrimental to neurons,promoting the development of neurodegenerative diseases.Nevertheless,c-Abl activity seems to be in a pivotal balance between healthy synaptic plasticity,regulating dendritic spines remodeling and gene expression after cognitive training,and synaptic dysfunction and loss in neurodegenerative diseases.Thus,c-Abl genetic ablation not only improves learning and memory and modulates the brain genetic program of trained mice,but its absence provides dendritic spines resiliency against damage.Therefo re,the present review has been designed to elu cidate the common links between c-Abl regulation of structural changes that involve the actin cytos keleton and organelles dynamics,and the transc riptional program activated during synaptic plasticity.By summarizing the recent discove ries on c-Abl functions,we aim to provide an overview of how its inhibition co uld be a potentially fruitful treatment to improve degenerative outcomes and delay memory loss.

Overexpression of mitogen-activated protein kinase phosphatase-1 in endothelial cells reduces blood-brain barrier injury in a mouse model of ischemic stroke

Ischemic stroke can cause blood-brain barrier(BBB)injury,which worsens brain damage induced by stroke.Abnormal expression of tight junction proteins in endothelial cells(ECs)can increase intracellular space and BBB leakage.Selective inhibition of mitogen-activated protein kinase,the negative regulatory substrate of mitogen-activated protein kinase phosphatase(MKP)-1,improves tight junction protein function in ECs,and genetic deletion of MKP-1 aggravates ischemic brain injury.However,whether the latter affects BBB integrity,and the cell type-specific mechanism underlying this process,remain unclear.In this study,we established an adult male mouse model of ischemic stroke by occluding the middle cerebral artery for 60 minutes and overexpressed MKP-1 in ECs on the injured side via lentiviral transfection before stroke.We found that overexpression of MKP-1 in ECs reduced infarct volume,reduced the level of inflammatory factors interleukin-1β,interleukin-6,and chemokine C-C motif ligand-2,inhibited vascular injury,and promoted the recovery of sensorimotor and memory/cognitive function.Overexpression of MKP-1 in ECs also inhibited the activation of cerebral ischemia-induced extracellular signal-regulated kinase(ERK)1/2 and the downregulation of occludin expression.Finally,to investigate the mechanism by which MKP-1 exerted these functions in ECs,we established an ischemic stroke model in vitro by depriving the primary endothelial cell of oxygen and glucose,and pharmacologically inhibited the activity of MKP-1 and ERK1/2.Our findings suggest that MKP-1 inhibition aggravates oxygen and glucose deprivation-induced cell death,cell monolayer leakage,and downregulation of occludin expression,and that inhibiting ERK1/2 can reverse these effects.In addition,co-inhibition of MKP-1 and ERK1/2 exhibited similar effects to inhibition of ERK1/2.These findings suggest that overexpression of MKP-1 in ECs can prevent ischemia-induced occludin downregulation and cell death via deactivating ERK1/2,thereby protecting the integrity of BBB,alleviating brain injury,and improving post-stroke prognosis.