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.

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.

Modulatory Effect of Rg_1 on the Activity of ProteinTyrosine Kinase of Lymphocytes in the Elderly

The effect of Rg1,a saponin extracted froin Panax ginseng, on the phenotype,receptor and the activity of protein tyrosine kinase (PTK) of lymphocytes isolated from 7 healthy oldpersons were studied. The CD25, CD45RA and CD45RO phenotypes of lymphocytes were 4eter-mined by indirect immunofluorescence technique. The percentage of CD25, CD45RA and CD45ROpositive lymphocytes was 38.3%±17.3%, 46.0% 15.1%, and 52.6%±14.1% respectively after incu-bation with PHA (5 μ±/ml) for 72 hours. However, there were 58.0%±12.5%, CD25, 64.1% ± 12.4%,CD45RA, and 74.0%±8.0%, CD45RO positive cells in the presence of Rg, ( 1μg/ml) along with PHA(5 μg/ml) over the sanie period of incubation. A significant increase was induced by Rgi (P<0.05).The activities of PTK in the cytoplasm and membrane of lymphocytes were measured by ELISAmcthod after incubation with PHA or PHA+Rg1. The absorbance value of PTK activity in cytoplasmafter 72 hr incubation was 0. 120±0.020 in PHA group, but 0. 1 38±0.015 in PHA+Rg1 group. In thelymphocyte membrane, it was 0.374± 0.060 in PHA group and 0.403 ± 0.008 in PHA+Rg1 group(P<0.001). These results showed that Rgi significantly arid simultaneously increased both the PT Kactivity and the expression of phenotype of lymphocytes.

EFFECT OF ACTIVE COMPOUNDS ISOLATED FROM PTERIS SEMIPINNATA L ON DNA TOPOISOMERASES AND TYROSINE PROTEIN KINASE AND EXPRESSION OF C-MYC IN LUNG ADENOCARCINOMA CELLS

Objective: To study the effect of active compound 6F and A from Pteris semipinnata L.(PsL) on the activities of DNA topoisomerase (TOPO) I and II, activities of cytosolic and membrane TPK, and expression of oncogene c-myc in lung adenocarcinoma cells. Methods: The effect of compound 6F and A on activities of cytosolic and membrane TPK was measured by scintillation counting; the effect of compound A on expression of oncogene c-myc was determined by flow cytometry indirect fluorimetry. Results: compound 6F and A could inhibit the activities of TOPO I, and they strongly inhibited the TOPO II in 0.01 mg/L and 10.0 mg/L respectively. Compound A slightly inhibited the activities of membrane TPK, but not the cytosolic one. Compound A could inhibit the expression of oncogene c-myc. Conclusion: Topoisomerases are target of compound 6F and A. Compound A could slightly inhibit the activities of TPK, and showed an inhibitory effect on the expression of oncogene c-myc.

ABNORMAL PROTEIN TYROSINE KINASES ASSOCIATED WITH HUMAN HAEMATOLOGICAL MALIGNANCIES

Objective: To survey the role of protein tyrosine kinases (PTKs) in the pathogenesis of several hematopoietic malignancies. Methods: By reviewing the published laboratory and clinical studies on PTK-related oncoproteins and their causative role in some leukemias and lymphomas. Results: Protein tyrosine kinases are key participants in signal transduction pathways that regulate cellular growth, activation and differentiations. Aberrant PTK activity resulting from gene mutation (often accompanying chromosome translocation) plays an etiologic role in several clonal hematopoietic malignancies. For example, the PTK product of the BCR-ABL fusion gene resulting from the t (9; 22) translocation exhibits several fold higher tyrosine kinase activity than the product of the ABL gene. Evidence suggests that the BCR-ABL oncoprotein alone is sufficient to case chronic myelogenous leukemia (CML) and other Ph positive acute leukemia. PTK over-activity resulting from chromosomal translocations creating TEL-ABL, TEL-JAK2 and TEL-PDGFRβ fusion proteins plays an important role in the pathogenesis of other types of leukemia. Another example occurs in anaplastic large cell lymphoma (ALCL). Experimental and clinical evidences indicate that translocations involving ALK gene on chromosome 2p23, most commonly resulting in an NPM-ALK fusion oncogene, result in constitutive activation of ALK and cause ALCL. This group of lymphomas is now named ALK positive lymphoma or ALKoma. Conclusion: Genetic lesions creating aberrant fusion proteins that result in excessive PTK activity are increasingly being recognized as central to the pathogenesis of hemotopoietic malignancies. These chimeric PTK molecules represent attractive disease-specific targets against which new classes therapeutic agents are being developed.

Effects of insulin receptor tyrosine protein kinase on insulin resistance after scalding in rats

After the rats were inflicted with 30% TBSA full thickness scalding on their back, the changes of insulin receptor tyrosine protein kinase (IRTPK) were studied on the 4th day postscalding with the phosphorylation of exogenous substrates stimulated with hepatic and muscular plasma membrane in order to explore the possible molecular mechanism of insulin resistance after thermal injury. It was found that insulin resistance appeared in the early stage postscalding while the basic value of phosphorylation of exogenous substrates stimulated with hepatic and muscular plasma membrane was increased and the activity of IPTPK to insulin stimulation was greatly suppressed as compared with the control. These facts suggest that the impaired responses of IRTPK to insulin stimulation may affect the down-stream signal transmission of the insulin receptors and then the signal coupling pathwayfor glucose transmembranous transportation and glycogen synthesis mediated by IRTPK is obstructed and insulinresistance develops.

Modulation of protein tyrosine phosphorylation in gastric mucosa during re-epithelization processes

AIM:To investigate the role of protein tyrosine phosphorylation in gastric wound formation and repair following ulceration. METHODS:Gastric lesions were induced in rats using restraint cold stress.To investigate the effect of oxidative and nitrosative cell stress on tyrosine phosphorylation during wound repair,total activity of protein tyrosine kinase(PTK),protein tyrosine phosphatase (PTP),antioxidant enzymes,nitric oxide synthase (NOS), 2',5'-oligoadenylate synthetase,hydroxyl radical and zinc levels were assayed in parallel. RESULTS:Ulcer provocation induced an immediate decrease in tyrosine kinase(40% in plasma membranes and 56% in cytosol,(P<0.05) and phosphatase activity (threefold in plasma membranes and 3.3-fold in cytosol),followed by 2.3-2.4-fold decrease (P<0.05) in protein phosphotyrosine content in the gastric mucosa. Ulceration induced no immediate change in superoxide dismutase (SOD) activity,30% increase (P<0.05) in catalase activity,2.3-fold inhibition (P<0.05) of glutathione peroxidase,3.3-fold increase (P<0.05) in hydroxyl radical content,and 2.3-fold decrease (P<0.05) in zinc level in gastric mucosa.NOS activity was three times higher in gastric mucosa cells after cold stress. Following ulceration,PTK activity increased in plasma membranes and reached a maximum on day 4 after stress (twofold increase,P<0.05),but remained inhibited(1.6-3-fold decrease on days 3,4 and 5,P<0.05) in the cytosol.Tyrosine phosphatases remained inhibited both in membranes and cytosol(1.5-2.4-fold,P< 0.05).NOS activity remained increased on days 1,2 and 3(3.8-,2.6-,2.2-fold,respectively,P<0.05).Activity of SOD increased 1.6 times(P<0.05)days 4 and 5 after stress.Catalase activity normalized after day 2. Glutathione peroxidase activity and zinc level decreased (3.3-and 2-fold,respectively,P<0.05)on the last day. Activity of 2',5'-oligoadenylate synthethase increased 2.8-fold (P<0.05) at the beginning,and 1.6-2.3-fold (P<0.05) during ulcer recuperation,and normalized on day 5,consistent with slowing of inflammation processes. CONCLUSION:These studies show diverse changes in total tyrosine kinase activity in gastric mucosa during the recovery process.Oxidative and nitrosative stress during lesion formation might lead to the observed reduction in tyrosine phosphorylation during ulceration.

Protein tyrosine phosphatase 1B regulates migration of ARPE-19 cells through EGFR/ERK signaling pathway

AIMTo evaluate whether protein tyrosine phosphatase 1B (PTP1B) contributed to initiate human retinal pigment epithelium cells (A)-19 migration and investigate the signaling pathways involved in this process.METHODSARPE-19 cells were cultured and treated with the siRNA-PTP1B. Expression of PTP1B was confirmed by quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR). AG1478 [a selective inhibitor of epidermal growth factor receptor (EGFR)] and PD98059 (a specific inhibitor of the activation of mitogen-activated protein kinase) were used to help to determine the PTP1B signaling mechanism. Western blot analysis verified expression of EGFR and extracellular signal-regulated kinase (ERK) in ARPE-19 cells. The effect of siRNA-PTP1B on cell differentiation was confirmed by immunostaining for &#x003b1;-smooth muscle actin (&#x003b1;-SMA) and qRT-PCR. Cell migration ability was analyzed by transwell chamber assay.RESULTSThe mRNA levels of PTP1B were reduced by siRNA-PTP1B as determined by qRT-PCR assay. SiRNA-PTP1B activated EGFR and ERK phosphorylation. &#x003b1;-SMA staining and qRT-PCR assay demonstrated that siRNA-PTP1B induced retinal pigment epithelium (RPE) cells to differentiate toward better contractility and motility. Transwell chamber assay proved that PTP1B inhibition improved migration activity of RPE cells. Treatment with AG1478 and PD98059 abolished siRNA-PTP1B-induced activation of EGFR and ERK, &#x003b1;-SMA expression and cell migration.CONCLUSIONPTP1B inhibition promoted myofibroblast differentiation and migration of ARPE-19 cells, and EGFR/ERK signaling pathway played important role in migration process.

Evolution of breast cancer therapeutics: Breast tumour kinase's role in breast cancer and hope for breast tumour kinase targeted therapy

There have been significant improvements in the detection and treatment of breast cancer in recent decades. However, there is still a need to develop more effective therapeutic techniques that are patient specific with reduced toxicity leading to further increases in patients' overall survival; the ongoing progress in understanding recurrence, resistant and spread also needs to be maintained. Better understanding of breast cancer pathology, molecular biology and progression as well as identification of some of the underlying factors involved in breast cancer tumourgenesis and metastasis has led to the identification of novel therapeutic targets. Over a number of years interest has risen in breast tumour kinase(Brk) also known as protein tyrosine kinase 6; the research field has grown and Brk has been described as a desirable therapeutic target in relation to tyrosine kinase inhibition as well as disruption of its kinase independent activity. This review will outline the current "state of play" with respect to targeted therapy for breast cancer, as well as discussing Brk's role in the processes underlying tumour development and metas-tasis and its potential as a therapeutic target in breast cancer.

Current and future treatment of anaplastic lymphoma kinase-rearranged cancer

Aberrant forms of the anaplastic lymphoma kinase(ALK) are involved in the pathogenesis of several types of cancer, including anaplastic large cell lymphoma, non-small-cell lung cancer(NSCLC), inflammatory myofibroblastic tumors, colorectal cancer, neuroblastoma and others. In general, the ALK catalytic domain is rearranged and fused to a dimerization domain encoded by an unrelated gene. Less frequently, full-length ALK is activated by point mutations. The common theme is unregulated firing of ALK downstream signalling, leading to uncontrolled cell division and increased cell survival. ALK-driven tumors can be treated with Crizotinib, an orally available dual ALK/MET inhibitor, currently approved for advanced ALK-positive NSCLCs. Crizotinibtreated patients achieve high response rates, with an excellent toxicity profile. However, drug-resistant disease often develops, particularly in NSCLC patients. The processes leading to drug resistance include both ALKdependent(point mutations or gene amplification), as well as ALK-independent mechanisms, which are here briefly discussed. Recently, Ceritinib has been approved for Crizotinib-refractory NSCLC, further extending patients' survival, but resistance again emerged. Novel ALK kinase inhibitors are currently under clinical development, showing great promise for improved efficacy in drugresistance disease. It is opinion of the author that drugresistance is likely to arise under any treatment, due to intrinsic heterogeneity and adaptability of cancer. To prevent or delay this phenomenon, we need to treat less advanced disease, with drugs that are rapidly effective in order not to allow enough time for tumor evolution, and we want to have more and more drugs with nonoverlapping resistance profiles, for subsequent lines of targeted therapy. Finally, the use of drug combinations may exponentially decrease the chances of resistance.

Effect of quercetin on activities of protein kinase C and tyrosine protein kinase from HL-60 cells

目的：研究槲皮素（Ｑｕｅ）对ＨＬ６０细胞中细胞溶质和胞膜蛋白激酶Ｃ（ＰＫＣ）、酪氨酸蛋白激酶（ＴＰＫ）活性的影响．方法：活细胞数的计数用苔盼兰拒染法；用组蛋白ⅢＳ、［γ３２Ｐ］ＡＴＰ与ＰＫＣ酶液一起保温测定ＰＫＣ活性；用聚谷氨酸·酪氨酸（４∶１）多肽）、［γ３２Ｐ］ＡＴＰ与ＴＰＫ酶液一起保温测定ＴＰＫ活性．结果：Ｑｕｅ对ＨＬ６０细胞的增殖有抑制作用，呈剂量依赖关系，处理４８小时后，其ＩＣ５０为２９（２２－３７）μｍｏｌ·Ｌ－１；在体外，Ｑｕｅ能强烈抑制细胞溶质ＰＫＣ和胞膜ＴＰＫ活性，其ＩＣ５０分别为：３１（２０－４８）μｍｏｌ·Ｌ－１，２４（１３－４５）μｍｏｌ·Ｌ－１，但不影响胞膜ＰＫＣ和细胞溶质ＴＰＫ活性．结论：这为Ｑｕｅ对癌细胞的生长有抑制作用与其抑制ＰＫＣ和／或ＴＰＫ有关提供了直接证据．

Treatment time influences the effects of a low-frequency pulsed electric field on synthesis of tyrosine hydroxylase and dopamine in PC12 cells

BACKGROUND： Electromagnetic radiation can influence dopamine （DA） synthesis in brain tissues or ceils, but electromagnetic frequencies, intensities, and radiation time can produce different effects. In addition, the signal pathway by which electromagnetic radiation influences DA synthesis remains controversial. OBJECTIVE： To determine tyrosine hydroxylase （TH） expression in PC12 cells and DA levels in cell culture media after different periods of low-frequency pulsed electric field （LF-PEF） stimulation, and to determine how LF-PEF signaling stimulates TH synthesis using inhibitors. DESIGN, TIME AND SETTING： A parallel, controlled, cell experiment was performed at the Laboratory of Cell Biology, School of Life Science, East China Normal University, between January and October 2006. MATERIALS： PC12 cells were purchased from the Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, China. Nerve growth factor was purchased from PeproTech, USA. The protein kinase A inhibitor, H-89, and mitogen-activated protein kinase kinase inhibitor, U0126, were purchased from Sigma, USA. METHODS： （1） Following routine culture in Dulbecco＇s modified eagle medium, primary PC12 cells were stimulated under LF-PEF （pulse frequency 50.Hz, pulse width 20 μs, peak field strength 1 V/m） for 5, 10, 15, 20, and 30 minutes. （2） Inhibitors （H-89 or U0126, 1 μmol/L） were added 30 minutes before LF-PEF stimulation for 10 minutes. MAIN OUTCOME MEASURES： （1） TH expression was determined by Western blot in PC12 cells at 0.5, 1,2, 3, and 4 days after LF-PEF stimulation. Similarly, DA was measured by high-performance liquid chromatography in media at 2, 3, 4, or 5 days after LF-PEE （2） TH expression was detected 1 day after H-89 or U0126 treatment and LF-PEE RESULTS： （1） Short-term LF-PEF stimulation （5 and 10 minutes） increased TH expression and media DA levels after short-term culture （2 days） （P 〈 0.01）, but both parameters decreased with longer culture （3 4 days） （P 〈 0.01）. Long-term LF-PEF stimulation （15, 20, or 30 minutes） decreased TH and DA synthesis, followed by a rapid increase （P 〈 0.01）. （2） H89 could completely inhibit TH expression in PC12 cells stimulated by LF-PEF for 10 minutes, while the inhibition rate of U0126 was 53.2%. CONCLUSION： Short-term LF-PEF first promotes then inhibits, while long-term LF-PEF first inhibits then promotes, TH and DA synthesis. LF-PEF stimulation regulates TH expression primarily by activating protein kinase A to regulate DA synthesis.

慢性肾小球肾炎患者MCP-1和sFlt-1表达与肾功能及预后的相关性研究

目的:分析慢性肾小球肾炎患者血清单核细胞趋化蛋白-1(MCP-1)和可溶性血管内皮细胞生长因子受体1(sFlt-1)水平变化及其与肾功能和预后的关系。方法:纳入2018-01—2020-03本院收治的慢性肾小球肾炎患者122例(研究组),选取同时期本院体检健康者128例(对照组)。研究组依据肾功能损害情况分为A组(肾功能正常16例)、B组(轻中度肾功能损害88例)、C组(重度肾功能损害18例);根据随访结局,将患者分为肾功能衰竭组(22例)和病情缓解组(100例)。采用酶联免疫吸附法(ELISA)检测受试者MCP-1、sFlt-1水平。采用全自动生化分析仪检测所有受试者血尿素氮(BUN)、血肌酐(Scr)水平,采用慢性肾脏疾病流行病学合作研究公式(CKD-EPI)估算肾小球滤过率(eGFR)。Pearson法分析MCP-1、sFlt-1与BUN、Scr、eGFR的相关性。采用受试者工作特征(ROC)曲线评价血清MCP-1、sFlt-1水平预测慢性肾小球肾炎患者预后的价值。结果:与对照组相比,研究组MCP-1、sFlt-1、BUN、Scr水平较高(P<0.05),eGFR较低(P<0.05)。C组BUN、Scr、MCP-1、sFlt-1水平明显高于A组、B组(P<0.05),B组BUN、Scr、MCP-1、sFlt-1水平明显高于A组(P<0.05)。Pearson相关性分析显示,MCP-1与BUN、Scr均呈正相关(P<0.05),与eGFR呈负相关(P<0.05),sFlt-1与BUN、Scr均呈正相关(P<0.05),与eGFR呈负相关(P<0.05)。与病情缓解组相比,肾功能衰竭组患者清中MCP-1、sFlt-1水平较高(P<0.05)。ROC分析显示,血清MCP-1、sFlt-1水平预测慢性肾小球肾炎患者预后的AUC分别为0.967、0.965,MCP-1联合sFlt-1预测慢性肾小球肾炎患者预后的AUC为0.984,灵敏度100.00%,特异度94.00%。结论:慢性肾小球肾炎患者血清MCP-1、sFlt-1水平明显上升,可作为患者预后评估的潜在生物学指标。

西藏地区结直肠癌免疫治疗和靶向治疗相关分子标志物的检测及意义

目的研究西藏地区结直肠癌中SWI/SNF相关、基质相关、肌动蛋白依赖性染色质调节因子A亚科成员4(SMARCA4)/Brahma相关基因1、V-raf鼠类肉瘤病毒癌基因同源物B(BRAF)、P53、程序性死亡受体1(PD-1)及程序性死亡配体1(PD-L1)免疫组织化学表达和BRAF、神经营养因子酪氨酸受体激酶(NTRK)基因改变情况,为西藏地区结直肠癌患者的靶向治疗及免疫治疗提供依据。方法收集2015年1月至2021年7月西藏自治区人民医院经手术切除病理确诊为结直肠癌病例64例,全部病例均进行SMARCA4、BRAF、P53、PD-1、PD-L1免疫组织化学染色和NTRK1、NTRK2、NTRK3融合基因荧光原位杂交检测及BRAF V600E基因突变PCR检测。结果64例结直肠癌病例男女比例1.21∶1,平均年龄(56.59±13.27)岁;46例(71.88%)位于结肠,18例(28.12%)位于直肠;60例(93.75%)为腺癌,4例(6.25%)为其他类型;11例(17.19%)为T1或T2期,53例(82.81%)为T3或T4期;24例(37.50%)出现淋巴结转移。免疫组织化学方面,64例中1例(1.56%)SMARCA4部分肿瘤细胞表达减弱或缺失,4例(6.25%)BRAF肿瘤细胞阳性表达,35例(54.69%)P53为突变型表达;45例(70.31%)PD-1肿瘤相关免疫细胞阳性比例分数<10%,19例(29.69%)≥10%;52例(81.25%)PD-L1联合阳性分数<10,12例(18.75%)≥10。64例NTRK1、NTRK2、NTRK3融合基因检测均为阴性;4例(6.25%)检测到BRAF V600E基因突变;1例SMARCA4表达缺失病例未检测到SMARCA4基因改变。PD-L1的表达与错配修复缺陷/高度微卫星不稳定和PD-1的高表达呈显著正相关(χ^(2)=10.223,P=0.001;χ^(2)=11.979,P=0.001)。结论西藏地区结直肠癌中较少出现SMARCA4表达减弱或缺失及NTRK融合基因改变,少数病例有BRAF V600E基因突变,Pan-TRK和BRAF免疫组织化学可作为NTRK融合基因及BRAF基因突变的初筛方法。错配修复缺陷/高度微卫星不稳定的病例中更容易出现PD-L1蛋白高表达,这部分患者有望获益于免疫治疗。P53突变与PD-L1表达无相关性,PD-1的高表达和PD-L1的高表达呈正相关。

右美托咪定调节JAK2/STAT3信号通路对老年胸腔镜患者术后认知功能的影响

目的探讨右美托咪定调节蛋白络氨酸激酶2(JAK2)/信号转导子与激活子3(STAT3)信号通路对老年胸腔镜患者术后认知功能的影响。方法前瞻性选取2020年8月至2023年6月于邯郸市第一医院行胸腔镜手术的老年患者96例,按随机数字表法分为观察组和对照组,每组各48例。观察组患者在全身麻醉插管后持续泵注右美托咪定,对照组给予等量0.9%氯化钠溶液泵注,术毕前30 min停止泵注。比较两组患者术前及术后1、3、5 d时认知功能[简易精神状态检查量表(MMSE)],术前及术后1 d时JAK2/STAT3信号通路相关蛋白(JAK2、P-JAK2和P-STAT3)水平,麻醉诱导前(T 0)、诱导5 min时(T 1)、术毕(T 2)及拔管时(T 3)血流动力学[平均动脉压(MAP)、心率]变化和不良反应发生率。结果观察组术后1、3 d的MMSE评分分别为(26.70±1.24)、(27.24±1.53)分,均显著高于对照组[(25.15±1.16)、(26.71±1.46)分],差异均有统计学意义(P<0.05)。观察组术后1 d的JAK2、P-JAK2、P-STAT3水平分别为0.31±0.07、0.43±0.08、0.37±0.07,均显著低于对照组(0.42±0.09、0.48±0.12、0.44±0.09),差异均有统计学意义(P<0.05)。观察组T 3时心率、MAP水平分别为(82.31±8.43)次/min、(87.43±9.01)mmHg,均显著低于对照组[(86.03±8.74)次/min、(92.41±9.64)mmHg],差异均有统计学意义(P<0.05)。两组患者不良反应发生率比较,差异无统计学意义(P>0.05)。结论右美托咪定可减少老年胸腔镜患者术后认知功能障碍的发生,这可能与JAK2/STAT3信号通路是氧化应激信号通路之一有关。

Role of protein tyrosine kinase in IL-1β induced activation of mitogen- activated protein kinase in fibroblast-like synoviocytes of rheumatoid arthritis

Obejctives To study mitogen activated protein kinase (MAPKs) activation in fibroblast like synoviocytes (FLS) of rheumatoid arthritis (RA) under the stimulation of IL 1β, and to elucidate the role of protein tyrosine kinase (PTK) in the activation of MAPKs Methods Primary cultures of RA FLS were used Western blot was applied to examine transient changes in protein tyrosine phosphorylation status and MAPKs activation in RA FLS stimulated with IL 1β at various doses, and over different periods Genistein, the specific PTK inhibitor, was used to evaluate the inhibitory role in activation of MAPKs by IL 1β Results IL 1β transiently increased protein tyrosine phosphorylation, and activated the MAPKs cascades (mainly ERK 2, JNK 2 and P 38 ) in RA FLS There was no obvious difference in MAPKs activation among different doses of IL 1β (1?IU/ml,10?IU/ml, 100?IU/ml), but the peak activation of ERK 2, JNK 2 and P 38 took place at 5?min, 15?min and 1?min, respectively, after stimulation with IL 1β The activation of ERK 2 was inhibited by genistein, but the inhibitory role on that of JNK and P 38 was relatively weak Conclusions During signal transduction of IL 1β in RA FLS, tyrosine phosphorylation was increased transiently, the MAPKs cascade was activated in a few minutes, and there was heterogenicity in the activation among three subfamily members PTK had a role in the activation of ERK, but had weak effects on that of JNK and P 38

Mechanism involved in the modulation of photoreceptor-specific cyclic nucleotidegated channel by the tyrosine kinase adapter protein Grb14

We recently found that growth factor receptor-bound(Grb)protein 14 is a novel physiological modulator of photoreceptor specific cyclic nucleotide-gated channel alpha subunit(CNGA1).Grb14 promotes the CNG channel closure through its Ras-associating(RA)domain.In the current study we show that this RA domain-mediated inhibition of rod CNG channel is electrostatic in nature.Grb14 competes with cGMP for the CNGA1 binding pocket and electrostatically interacts with Arg^(559) through a negatively chargedβ-turn at its RA domain.Moreover,the three Glu residues(180–182)in Grb14 are absolutely critical for electrostatic interaction with the cGMP binding pocket and resultant inhibition.Our study also demonstrates that substitution of Lys^(140) for Ala or in combination with polyglutamte mutants of Grb14 results in a significantly reduced binding with CNGA1.These results suggest that in addition to Glu^(180–182) and Lys^(140),other residues in Grb14 may be involved in the electrostatic interaction with CNGA1.The RA domain is highly conserved among the members of Grb7 family of proteins,which includes Grb7,Grb10 and Grb14.Further,only Grb14 is able to modulate the channel activity,but not Grb7 and Grb10.All together,it suggests the existence of a divergence in RA domains among the members of the Grb7 family.

MiR-28-5p靶向DOK4对口腔鳞状细胞癌细胞增殖的影响

目的探讨微小RNA(miR)-28-5p通过靶向酪氨酸激酶下游蛋白4(DOK4)对口腔鳞状细胞癌细胞增殖的调控作用。方法下载癌症基因组图谱(TCGA)口腔癌数据库,分析miR-28-5p、DOK4与口腔鳞状细胞癌临床表型的关系;转染miR-28-5p模拟物(mimics)、miR-28-5p抑制剂(inhibitor)及对照物(NC)、pcDNA3.1-DOK4及空载体(Vector)、DOK4干扰序列(siDOK4)。CCK-8法和克隆集落形成实验检测口腔鳞状细胞癌的细胞增殖能力;检测各组细胞的抗氧化能力和细胞活性氧(ROS)含量;双荧光素酶报告基因实验验证miR-28-5p与DOK4的靶向关系;观察DOK4过表达对细胞增殖和口腔鳞状细胞癌裸鼠移植瘤生长的影响。结果生物信息学分析显示,相较于癌旁口腔组织,miR-28-5p在口腔鳞状细胞癌组织中表达上调,DOK4 mRNA下调(P<0.05);临床分期Ⅳ期、M 1期、G 3~G 4分级患者miR-28-5p水平高于临床分期Ⅰ~Ⅲ期、M 0期、G 1~G 2分级者(P<0.05);临床分期Ⅳ期、N 1期、G_(3)~G_(4)分级患者DOK4 mRNA水平低于临床分期Ⅰ~Ⅲ期、N 0期、G_(1)~G_(2)分级者(P<0.05);DOK4高表达组无进展生存期和总生存期均高于DOK4低表达组(P<0.05)。与miR-NC组比较,miR-28-5p inhibitor组miR-28-5p水平、细胞活性和集落形成数降低(P<0.05)。与miR-NC组比较,miR-28-5p mimics组DOK4 mRNA和蛋白表达水平降低(P<0.05);与Vector组比较,DOK4过表达组细胞和移植瘤组织中DOK4 mRNA和蛋白表达升高,细胞活性、集落形成数、肿瘤体积及重量降低(P<0.05);与miR-28-5p inhibitor组比较,miR-28-5p inhibitor+siDOK4组的DOK4 mRNA和蛋白表达水平降低,细胞增殖活性、集落形成数、还原型烟酰胺腺嘌呤二核苷酸/烟酰胺腺嘌呤二核苷酸(NADPH/NADP+)、谷胱甘肽/氧化性谷胱甘肽(GSH/GSSG)升高,ROS含量降低(P<0.05)。结论miR-28-5p在口腔鳞状细胞癌中表达上调,通过靶向抑制DOK4表达,降低ROS水平,促进细胞增殖。

基于BDNF/TrkB/CREB通路研究六味地黄丸对丙戊酸钠诱导的孤独症谱系障碍模型仔鼠的作用机制

目的基于脑源性神经营养因子(brain-derived neurotrophic factor,BDNF)/酪氨酸激酶受体B(tyrosine kinase receptor B,TrkB)/cAMP反应元件结合蛋白(cAMP response element binding protein,CREB)通路,探讨六味地黄丸对丙戊酸钠(sodium valproate,VPA)诱导的孤独症谱系障碍(autism spectrum disorder,ASD)仔鼠的作用机制。方法将13只SD孕鼠随机分为两组,其中10只孕鼠在第12.5天时腹腔注射VPA溶液(600 mg·kg^(-1))为VPA组,另外3只孕鼠注射等体积生理盐水为对照组。第21天对两组雄性仔鼠开展行为学检测,筛选出符合ASD疾病模型的仔鼠30只,随机分为模型组(等体积生理盐水),维生素D组(1480 IU·kg^(-1)),六味地黄丸高(3 g·kg^(-1))、中(1.5 g·kg^(-1))、低(0.75 g·kg^(-1))剂量组,每组6只。正常雄性仔鼠6只,设为空白组(等体积生理盐水)。各组仔鼠连续灌胃14 d,1次/d,给药后再次开展行为学检测。尼氏染色观察各组仔鼠海马组织神经元形态学变化,比色法检测各组仔鼠海马组织中谷氨酸(glutamic acid,GLU)、γ-氨基丁酸(gamma-aminobutyric acid,GABA)含量;qRT-PCR检测各组仔鼠海马组织中BDNF、TrkB、CREB mRNA相对表达。结果与对照组比较,VPA组仔鼠体质量、身长、尾长更小(P<0.05)。与空白组比较,模型组社交障碍症状明显(P<0.01),焦虑障碍症状明显(P<0.01),重复刻板行为增多(P<0.05或P<0.01),海马神经元结构损伤,GLU升高(P<0.01)、GABA下降(P<0.01),BDNF、TrkB、CREB mRNA表达降低(P<0.05或P<0.01);与模型组比较,维生素D组及六味地黄丸中、低剂量组仔鼠社交能力增强(P<0.05或P<0.01),焦虑障碍减轻(P<0.05或P<0.01),重复刻板行为减少(P<0.01或P<0.05),海马神经元结构明显复原,GLU下降(P<0.01),BDNF、TrkB、CREB mRNA表达增加(P<0.05或P<0.01),六味地黄丸中、低剂量组GABA上升(P<0.05或P<0.01)。结论六味地黄丸能显著改善VPA诱导的ASD仔鼠行为表现,增强海马组织神经元的再生与修复,其机制可能与平衡GLU、GABA水平,上调仔鼠海马组织中BDNF/TrkB/CREB的表达有关。

神经生长因子及其受体在高原牦牛与平原黄牛端脑中的比较分析

为探究神经生长因子(NGF)及其高亲和力受体酪氨酸蛋白激酶A(TrkA)在高原牦牛(Bos grunniens)与平原黄牛(Bos taurus)端脑组织中表达与分布的差异,本研究采集不同海拔地区的成年牦牛与黄牛端脑不同组织(n=5),利用免疫组织化学技术(IHC)、实时荧光定量PCR(qRT-PCR)以及蛋白免疫印迹技术(WB)对NGF和TrkA在牦牛与黄牛端脑各区中的定位特征及表达水平进行比较。IHC结果显示,两种因子在牦牛与黄牛端脑各区中的分布与定位特征基本一致,主要在神经元胞质、神经胶质细胞及血管内壁中表达,其蛋白免疫阳性反应强度整体表现为牦牛高于黄牛。qRT-PCR结果显示,牦牛的NGF基因表达量在额叶皮质、大脑白质及枕叶皮质中低于黄牛或无差异,在其余区域中显著高于黄牛(P<0.05);TrkA基因表达量仅在大脑白质中与黄牛无显著差异,其余区域中显著高于黄牛(P<0.05)。WB结果显示,牦牛的NGF蛋白表达量仅在大脑白质中低于黄牛,其余区域均显著高于黄牛(P<0.05);牦牛的TrkA蛋白表达量在额叶皮质、大脑白质及枕叶皮质中低于黄牛或无差异,其余区域中显著高于黄牛(P<0.05)。综上,两种因子在牦牛端脑部分组织表达上调可能与低氧刺激有关,推测二者在低氧条件下协同发挥内源性神经保护作用,以维持动物机体正常的生理活动。本研究结果为进一步探究NGF和TrkA在牦牛低氧适应性方面发挥作用提供了理论依据。