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.

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.

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.

Optimal sequential therapy using tyrosine kinase inhibitors as the first-line treatment in patients with metastatic renal cell carcinoma: A nationwide multicenter study

Objective:The purpose of the study was to identify the best sequence of therapy beginning with a tyrosine kinase inhibitor(TKI)as the first-line therapy for patients with metastatic renal cell carcinoma(mRCC)in terms of overall survival(OS),progression-free survival(PFS),and rates of discontinuation and adverse effects during the treatment period.Methods:This is a retrospective,nationwide multicenter study of patients with mRCC after diagnosis at 10 different tertiary medical centers in Korea from January 1992 to December 2017.We focused on patients at either“favorable”or“intermediate”risk according to the International mRCC Database Consortium criteria,and they were followed up(median 335 days).Finally,a total of 1409 patients were selected as the study population.We generated a Cox proportional hazard model adjusted for covariates,and the different therapy schemes were statistically tested in terms of OS as well as PFS.In addition,frequencies of discontinuation and adverse events were compared among the therapy schemes.Results:Of the primary patterns of treatment sequences(24 sequences),“sunitinib epazopanib”and“sunitinibeeverolimuseimmunotherapy”showed the most beneficial results in both OS and PFS with significantly lower hazards than“sunitinib”,which is the most commonly treated agent in Korea.Considering that the“TKIeTKI”structure showed relatively higher discontinuation rates with higher adverse effects,the overall beneficial sequence would be“sunitinibeeverolimuseimmunotherapy”.Conclusion:Among several sequential therapy starting with TKIs,“sunitinibeeverolimuse immunotherapy”was found to be the best scheme for mRCC patients with“favorable”or“intermediate”risks.

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.

Piperlongumine in combination with EGFR tyrosine kinase inhibitors for the treatment of lung cancer cells

Objectives:EGFR tyrosine kinase inhibitor(EGFR-TKI)therapies such as erlotinib and gefitinib are approved for the treatment of non-small cell lung cancer(NSCLC).However,the high incidence of acquired resistance to these EGFR-TKIs may preclude their effectiveness.Piperlongumine(PPL),an extract from the long pepper fruit(Piper longum),has been shown to possess anticancer properties.The purpose of the study was to investigate piperlongumine as an anticancer agent and to study a combination treatment approach with EGFR-TKIs against lung cancer cells.Methods:Anticancer efficacy of PPL,erlotinib(ERL),gefitinib(GEF),and cisplatin(CIS)were investigated in H1299 and H1975 cell lines.Cells were treated with PPL,ERL,GEF,and CIS alone,and in combination,cell viability was determined after 72 h.The mechanism of PPL-induced cytotoxicity was investigated via reactive oxygen species(ROS)induction,and apoptosis induction using acridine orange/ethidium bromide staining and flow cytometry.The effect of treatment on EGFR-mediated oncogenic signaling was investigated by immunoblotting for mitogenic and apoptotic markers.Results:PPL exhibited a potent cytotoxic effect in H1299 and H1975 cells compared to ERL,GEF,and CIS.Combination treatments of PPL with GEF and ERL showed significant reductions in cancer cells compared to control in both cell lines,which were associated with apoptotic induction,but without significant ROS induction.Compared to control,PPL with GEF significantly increased apoptotic cell death in H1975as confirmed with flow cytometry.Treatment with PPL alone and in combination induced anti-mitogenic and apoptotic responses at the molecular level.Conclusion:PPL sensitized lung cancer cells to EGFR-TKI and induced potent cytotoxic effects at low concentrations.

Protein tyrosine phosphatase non-receptor Ⅱ:A possible biomarker of poor prognosis and mediator of immune evasion in hepatocellular carcinoma

BACKGROUND The incidence of primary liver cancer is increasing year by year.In 2022 alone,more than 900000 people were diagnosed with liver cancer worldwide,with hepatocellular carcinoma(HCC)accounting for 75%-85%of cases.HCC is the most common primary liver cancer.China has the highest incidence and mortality rate of HCC in the world,and it is one of the malignant tumors that seriously threaten the health of Chinese people.The onset of liver cancer is occult,the early cases lack typical clinical symptoms,and most of the patients are already in the middle and late stage when diagnosed.Therefore,it is very important to find new markers for the early detection and diagnosis of liver cancer,improve the therapeutic effect,and improve the prognosis of patients.Protein tyrosine phosphatase non-receptor 2(PTPN2)has been shown to be associated with colorectal cancer,triple-negative breast cancer,non-small cell lung cancer,and prostate cancer,but its biological role and function in tumors remain to be further studied.AIM To combine the results of relevant data obtained from The Cancer Genome Atlas(TCGA)to provide the first in-depth analysis of the biological role of PTPN2 in HCC.METHODS The expression of PTPN2 in HCC was first analyzed based on the TCGA database,and the findings were then verified by immunohistochemical staining,quantitative real-time polymerase chain reaction(qRT-PCR),and immunoblotting.The value of PTPN2 in predicting the survival of patients with HCC was assessed by analyzing the relationship between PTPN2 expression in HCC tissues and clinicopathological features.Finally,the potential of PTPN2 affecting immune escape of liver cancer was evaluated by tumor immune dysfunction and exclusion and immunohistochemical staining.RESULTS The results of immunohistochemical staining,qRT-PCR,and immunoblotting in combination with TCGA database analysis showed that PTPN2 was highly expressed and associated with a poor prognosis in HCC patients.Kyoto Encyclopedia of Genes and Genomes enrichment analysis showed that PTPN2 was associated with various pathways,including cancer-related pathways,the Notch signaling pathway,and the MAPK signaling pathway.Gene Set Enrichment Analysis showed that PTPN2 was highly expressed in various immune-related pathways,such as the epithelial mesenchymal transition process.A risk model score based on PTPN2 showed that immune escape was significantly enhanced in the high-risk group compared with the low-risk group.CONCLUSION This study investigated PTPN2 from multiple biological perspectives,revealing that PTPN2 can function as a biomarker of poor prognosis and mediate immune evasion in HCC.

Clinical significance of upregulated Rho GTPase activating protein 12 causing resistance to tyrosine kinase inhibitors in hepatocellular carcinoma

BACKGROUND Hepatocellular carcinoma(HCC)is a major health challenge with high incidence and poor survival rates in China.Systemic therapies,particularly tyrosine kinase inhibitors(TKIs),are the first-line treatment for advanced HCC,but resistance is common.The Rho GTPase family member Rho GTPase activating protein 12(ARHGAP12),which regulates cell adhesion and invasion,is a potential therapeutic target for overcoming TKI resistance in HCC.However,no studies on the expression of ARHGAP12 in HCC and its role in resistance to TKIs have been reported.AIM To unveil the expression of ARHGAP12 in HCC,its role in TKI resistance and its potential associated pathways.METHODS This study used single-cell RNA sequencing(scRNA-seq)to evaluate ARHGAP12 mRNA levels and explored its mechanisms through enrichment analysis.CellChat was used to investigate focal adhesion(FA)pathway regulation.We integrated bulk RNA data(RNA-seq and microarray),immunohistochemistry and proteomics to analyze ARHGAP12 mRNA and protein levels,correlating with clinical outcomes.We assessed ARHGAP12 expression in TKI-resistant HCC,integrated conventional HCC to explore its mechanism,identified intersecting FA pathway genes with scRNA-seq data and evaluated its response to TKI and immunotherapy.RESULTS ARHGAP12 mRNA was found to be highly expressed in malignant hepatocytes and to regulate FA.In malignant hepatocytes in high-score FA groups,MDK-[integrin alpha 6(ITGA6)+integrinβ-1(ITGB1)]showed specificity in ligand-receptor interactions.ARHGAP12 mRNA and protein were upregulated in bulk RNA,immunohistochemistry and proteomics,and higher expression was associated with a worse prognosis.ARHGAP12 was also found to be a TKI resistance gene that regulated the FA pathway.ITGB1 was identified as a crossover gene in the FA pathway in both scRNA-seq and bulk RNA.High expression of ARHGAP12 was associated with adverse reactions to sorafenib,cabozantinib and regorafenib,but not to immunotherapy.CONCLUSION ARHGAP12 expression is elevated in HCC and TKI-resistant HCC,and its regulatory role in FA may underlie the TKI-resistant phenotype.

Present and prospect of transarterial chemoembolization combined with tyrosine kinase inhibitor and PD-1 inhibitor for unresectable hepatocellular carcinoma

In this editorial,we comment on the article(World J Gastrointest Oncol 2024;16:1236-1247),which is a retrospective study of transarterial chemoembolization(TACE)combined with multi-targeted tyrosine kinase inhibitor(TKI)and programmed cell death protein-1(PD-1)inhibitor for the treatment of unresectable hepatocellular carcinoma(HCC).Herein,we focus specifically on the mechanisms of this triple therapy,administration sequence and selection of each medication,and implications for future clinical trials.Based on the interaction mechanisms between medications,the triple therapy of TACE+TKI+PD-1 is proposed to complement the deficiency of each monotherapy,and achieve synergistic antitumor effects.Although this triple therapy has been evaluated by several retrospective trials,it is still controversial whether the triple therapy achieves better clinical benefits,due to the flawed study design and heterogeneity in medications.In addition,the administration sequence,which may greatly affect the clinical benefit,needs to be fully considered at clinical decision-making for obtaining better prognosis.We hope that this editorial could contribute to the design and optimization of future trials.

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.

Pan-TRK positive uterine sarcoma in immunohistochemistry without neurotrophic tyrosine receptor kinase gene fusions:A case report

BACKGROUND The classification of uterine sarcomas is based on distinctive morphological and immunophenotypic characteristics,increasingly supported by molecular genetic diagnostics.Data on neurotrophic tyrosine receptor kinase(NTRK)gene fusionpositive uterine sarcoma,potentially aggressive and morphologically similar to fibrosarcoma,are limited due to its recent recognition.Pan-TRK immunohistochemistry(IHC)analysis serves as an effective screening tool with high sensitivity and specificity for NTRK-fusion malignancies.CASE SUMMARY We report a case of a malignant mesenchymal tumor originating from the uterine cervix,which was pan-TRK IHC-positive but lacked NTRK gene fusions,accompanied by a brief literature review.A 55-year-old woman presented to the emergency department with abdominal pain and distension,exhibiting significant ascites and multiple solid pelvic masses.Pelvic examination revealed a tumor encompassing the uterine cervix,extending to the vagina and uterine corpus.A punch biopsy of the cervix indicated NTRK sarcoma with positive immunochemical pan-TRK stain.However,subsequent next generation sequencing revealed no NTRK gene fusion,leading to a diagnosis of poorly differentiated,advanced-stage sarcoma.CONCLUSION The clinical significance of NTRK gene fusion lies in potential treatment with TRK inhibitors for positive sarcomas.Identifying such rare tumors is crucial due to the potential applicability of tropomyosin receptor kinase inhibitor treatment.

Advanced lung adenocarcinoma with EGFR 19-del mutation transforms into squamous cell carcinoma after EGFR tyrosine kinase inhibitor treatment

In this editorial we comment on the article by Ji et al.We focus specifically on the EGFR tyrosine kinase inhibitor(EGFR-TKI)treatment and the development of drug resistance to EGFR-TKIs.

KAT7/HMGN1 signaling epigenetically induces tyrosine phosphorylation-regulated kinase 1A expression to ameliorate insulin resistance in Alzheimer’s disease

BACKGROUND Epidemiological studies have revealed a correlation between Alzheimer’s disease(AD)and type 2 diabetes mellitus(T2D).Insulin resistance in the brain is a common feature in patients with T2D and AD.KAT7 is a histone acetyltransferase that participates in the modulation of various genes.AIM To determine the effects of KAT7 on insulin patients with AD.METHODS APPswe/PS1-dE9 double-transgenic and db/db mice were used to mimic AD and diabetes,respectively.An in vitro model of AD was established by Aβstimulation.Insulin resistance was induced by chronic stimulation with high insulin levels.The expression of microtubule-associated protein 2(MAP2)was assessed using immunofluorescence.The protein levels of MAP2,Aβ,dual-specificity tyrosine phosphorylation-regulated kinase-1A(DYRK1A),IRS-1,p-AKT,total AKT,p-GSK3β,total GSK3β,DYRK1A,and KAT7 were measured via western blotting.Accumulation of reactive oxygen species(ROS),malondialdehyde(MDA),and SOD activity was measured to determine cellular oxidative stress.Flow cytometry and CCK-8 assay were performed to evaluate neuronal cell death and proliferation,respectively.Relative RNA levels of KAT7 and DYRK1A were examined using quantitative PCR.A chromatin immunoprecipitation assay was conducted to detect H3K14ac in DYRK1A.RESULTS KAT7 expression was suppressed in the AD mice.Overexpression of KAT7 decreased Aβaccumulation and MAP2 expression in AD brains.KAT7 overexpression decreased ROS and MDA levels,elevated SOD activity in brain tissues and neurons,and simultaneously suppressed neuronal apoptosis.KAT7 upregulated levels of p-AKT and p-GSK3βto alleviate insulin resistance,along with elevated expression of DYRK1A.KAT7 depletion suppressed DYRK1A expression and impaired H3K14ac of DYRK1A.HMGN1 overexpression recovered DYRK1A levels and reversed insulin resistance caused by KAT7 depletion.CONCLUSION We determined that KAT7 overexpression recovered insulin sensitivity in AD by recruiting HMGN1 to enhance DYRK1A acetylation.Our findings suggest that KAT7 is a novel and promising therapeutic target for the resistance in AD.

Receptor tyrosine kinase-like orphan receptor 1:A novel antitumor target in gastrointestinal cancers

Receptor tyrosine kinase-like orphan receptor 1(ROR1)is a member of the type I receptor tyrosine kinase family.ROR1 is pivotal in embryonic development and cancer,and serves as a biomarker and therapeutic target.It has soluble and membrane-bound subtypes,with the latter highly expressed in tumors.ROR1 is conserved throughout evolution and may play a role in the development of gastrointestinal cancer through multiple signaling pathways and molecular mechanisms.Studies suggest that overexpression of ROR1 may increase tumor invasiveness and metastasis.Additionally,ROR1 may regulate the cell cycle,stem cell characteristics,and interact with other signaling pathways to affect cancer progression.This review explores the structure,expression and role of ROR1 in the development of gastrointestinal cancers.It discusses current antitumor strategies,outlining challenges and prospects for treatment.

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.

Effect of a novel tyrosine kinase inhibitor nintedanib on bFGF and VEGF concentrations in a rabbit retinal vein occlusion model

AIM:To evaluate whether a novel tyrosine kinase inhibitor nintedanib could inhibit basic fibroblast growth factor(bFGF)and vascular endothelial growth factor(VEGF)simultaneously for retinal vascular disease in vivo.METHODS:After a laser induced rabbit retinal vein occlusion(RVO)model was made,0.5 mg of nintedanib was injected intravitreally in the left eye on the third day while the right eye was as a control.Intracameral samples were taken on the day before laser treatment and days 1,3,7,14,21,and 28 after treatment.Enzyme-linked immunosorbent assay(ELISA)was used to test the bFGF and VEGF-A concentrations in the aqueous humor.RESULTS:Both bFGF and VEGF-A rose significantly on the third day after laser treatment in both eyes.In the control eye the bFGF concentration peaked on the 14th day while the VEGF-A concentration dropped rapidly soon after the third day.After nintadanib injection in the study eye,both bFGF and VEGF-A showed a significant reduction on the 4th day(7th day after laser treatment)when compared to the control eye,and kept on low level in the following several weeks.CONCLUSION:Intravitreal injection of nintedanib can inhibit the expression of bFGF and VEGF in the process of RVO model to a certain extent,which is expected to become a new method for the treatment of retinal vascular diseases or fibrotic diseases.

Tyrosine kinase inhibitors and human epidermal growth factor receptor-2 positive breast cancer

The body of evidence investigating human epidermal growth factor receptor-2(HER2)directed therapy in patients with breast cancer(BC)has been growing within the last decade.Recently,the use of tyrosine kinase inhibitors(TKIs)has been of particular interest in the treatment of human malignancies.This literature commentary is intended to highlight the most recent findings associated with the widely-studied TKI agents and their clinical significance in improving the outcomes of HER2 positive BC.

Rituximab combined with Bruton tyrosine kinase inhibitor to treat elderly diffuse large B-cell lymphoma patients: Two case reports

BACKGROUND Diffuse large B-cell lymphoma(DLBCL)is a common aggressive non-Hodgkin's lymphoma(NHL),accounting for 30%-40%of adult NHLs.This report aims to explore the efficacy and safety of rituximab combined with Bruton tyrosine kinase inhibitors(BTKis)in the treatment of elderly patients with DLBCL.CASE SUMMARY The clinical data of two elderly patients with DLBCL who received rituximab combined with BTKi in our hospital were retrospectively analyzed,and the literature was reviewed.The patients were treated with chemotherapy using the R-miniCHOP regimen for two courses.Then,they received rituximab in combination with BTKi.CONCLUSION The treatment experience in these cases demonstrates the potential efficacy of rituximab combined with BTKi to treat elderly DLBCL patients,thus providing a new treatment strategy.

N-methyl-D-aspartate receptors mediate diphosphorylation of extracellular signal-regulated kinases through Src family tyrosine kinases and Ca^2＋/calmodulin-dependent protein kinase Ⅱ in rat hippocampus after cerebral ischemia

Objective： Extracellular signal-regulated kinases （ERKs） can be activated by calcium signals. In this study, we investigated whether calcium-dependent kinases were involved in ERKs cascade activation after global cerebral ischemia. Methods Cerebral ischemia was induced by four-vessel occlusion, and the calcium-dependent proteins were detected by immunoblot. Results Lethal-simulated ischemia significantly resulted in ERKs activation in N-methyl-D-aspartate （NMDA） receptor-dependent manner, accompanying with differential upregulation of Src kinase and Ca^2＋/calmodulin-dependent protein kinase Ⅱ （CaMKⅡ） activities. With the inhibition of Src family tyrosine kinases or CaMKⅡ by administration of PP2 or KN62, the phosphorylation of ERKs was impaired dramatically during post-ischemia recovery. However, ischemic challenge also repressed ERKs activity when Src kinase was excessively activated. Conclusions Src family tyrosine kinases and CaMKⅡ might be involved in the activation of ERKs mediated by NMDA receptor in response to acute ischemic stimuli in vivo, but the intense activation of Src kinase resulted from ischemia may play a reverse role in the ERKs cascade.

Role of spleen tyrosine kinase in liver diseases

Spleen tyrosine kinase (SYK),a non-receptor tyrosine kinase,is expressed in most hematopoietic cells and non-hematopoietic cells and play a crucial role in both immune and non-immune biological responses.SYK mediate diverse cellular responses via an immune-receptor tyrosine-based activation motifs (ITAMs)-dependent signalling pathways,ITAMs-independent and ITAMs-semidependent signalling pathways.In liver,SYK expression has been observed in parenchymal (hepatocytes) and non-parenchymal cells (hepatic stellate cells and Kupffer cells) and found to be positively correlated with the disease severity.The implication of SYK pathway has been reported in different liver diseases including liver fibrosis,viral hepatitis,alcoholic liver disease,non-alcoholic steatohepatitis and hepatocellular carcinoma.Antagonism of SYK pathway using kinase inhibitors have shown to attenuate the progression of liver diseases thereby suggesting SYK as a highly promising therapeutic target.This review summarizes the current understanding of SYK and its therapeutic implication in liver diseases.