不同位点磷酸化Src酪氨酸激酶与食管鳞状细胞癌的关系

Objective To determine the relationship between phospholation of Src tyrosine kinase at different sites and esophageal squamous cell carcinoma (ESCC). Methods Thirty cases of ESCC paraffin-embedded tissue blocks and 3 cases of fresh ESCC tissue samples were collected, and human ESCC TE1 cells were cultured. The protein expression level of phosphorylation of Src tyrosine kinase at different sites was detected by using immunohistochemical staining, Western blotting and immunofluorescence. Results Py416Src protein expression level was higher than Py527Src in ESCC (P＜0.05). Conclusion Phosphorylation of Src tyrosine kinase at different sites plays a critical role in pathogenesis of ESCC.     

不同位点磷酸化Src酪氨酸激酶与食管鳞状细胞癌的关系

Objective To determine the relationship between phospholation of Src tyrosine kinase at different sites and esophageal squamous cell carcinoma (ESCC). Methods Thirty cases of ESCC paraffin-embedded tissue blocks and 3 cases of fresh ESCC tissue samples were collected, and human ESCC TE1 cells were cultured. The protein expression level of phosphorylation of Src tyrosine kinase at different sites was detected by using immunohistochemical staining, Western blotting and immunofluorescence. Results Py416Src protein expression level was higher than Py527Src in ESCC (P＜0.05). Conclusion Phosphorylation of Src tyrosine kinase at different sites plays a critical role in pathogenesis of ESCC.     

Tollip参与Src家族酪氨酸激酶Fyn在人食管鳞状细胞癌中负调控机制

目的 探讨人食管鳞状细胞癌中Tollip对Src家族酪氨酸激酶Fyn表达的负调控机制.方法 收集3例新鲜食管鳞状细胞癌组织(ESCC)和食管正常黏膜上皮组织(UNR),采用免疫印迹法分析Tollip蛋白表达水平的变化.同时转染人Tollip质粒DNA人TE1细胞株中观察其对Fyn表达的影响.结果　免疫印迹结果　显示食管鳞癌组织Tollip蛋白表达低于食管正常黏膜组织.转染Tollip质粒DNA可以降低人食管鳞状细胞癌TE1细胞中Fyn的表达.结论 Tollip可能是人食管鳞状细胞癌中Src家族酪氨酸激酶ryn的负调控因子,在食管鳞状细胞癌的发生发展过程中起重要作用.

Abstract：

Objective To determine the relationship between Src family tyrosine kinases Fyn expression and Toll-interacting protein ( Tollip ) in human esophageal squamous cell carcinoma ( ESCC ).Methods The Tollip expression was detected in 3 cases of ESCC and compared to the unremarkable epithelium by Western blotting. Tollip plasmid DNA ( 1 μg) was transfected into TE1 cells and the Fyn/Tollip expression was examined by Western blotting. Results The Tollip expression level was lower in ESCC group than in UNR group. Tollip decreased Fyn protein expression in TE1 cells. Conclusion Tollip may act as a negative regulator of Fyn in human ESCC, and play an important role in human ESCC progress.     

Srcasm负调控Src家族酪氨酸激酶Fyn在人食管鳞状细胞癌TE1细胞株中的表达

目的 观察人食管鳞状细胞癌TE1细胞株中Srcasm对Src家族酪氨酸激酶Fyn表达的影响.方法 分别转染0、0.25、0.5、1.0、2.0 μg人Srcasm质粒DNA入TE1细胞株中观察其对Fyn表达的影响.结果 转染Srcasm质粒DNA可以降低人食管鳞状细胞癌TE1细胞中Fyn的表达,且呈剂量依赖性.结论 人食管鳞状细胞癌中Srcasm可能是Src家族酪氨酸激酶Fyn的负调控因子,在食管鳞状细胞癌的发生发展过程中起重要作用.     

Src家族酪氨酸激酶Fyn在人食管鳞状细胞癌中的表达

目的 探讨食管鳞状细胞癌组织中Fyn的表达水平及其意义.方法 收集13例食管鳞状细胞癌组织(ESCC)和10例食管正常黏膜上皮组织(UNR),采用免疫组织化学法和免疫印迹法分析食管鳞状细胞癌组织及食管正常黏膜组织Fyn蛋白表达水平的变化.结果 免疫组织化学染色显示食管鳞状细胞癌组织中Fyn蛋白表达水平(9.68±2.31)高于食管正常黏膜组织中染色指数(3.21±1.25),差异有统计学意义(P<0.01).免疫印迹结果亦显示食管鳞癌组织中Fyn蛋白表达强于食管正常黏膜组织.结论 Fyn蛋白在食管鳞状细胞癌组织中高表达,提示Fyn基因在食管鳞状细胞癌的发生发展过程中可能起重要作用.     

胆管细胞癌酪氨酸激酶激活及其磷酸化酶分布

目的:探讨胆管细胞癌组织酪氨酸磷酸化信号通路变化及相关分子情况,以寻找新的治疗靶点。方法:免疫亲和、LC-MS/MS分析识辨胆管癌病人(n=23)750多种不同蛋白质中1 000多个酪氨酸磷酸化位点。结果:胆管细胞癌在DDR1、EPHA2、EGFR和ROS1表现最高水平酪氨酸激酶磷酸化,高表达DDR1、EPHA2、ROS1酪氨酸激酶活性(n=18,78%),低表达或不表达RTK活性(n=5,22%);癌旁组织EGFR、AXL、EPHB4和PDGFRA表现出最高水平酪氨酸磷酸化;肿瘤组织和癌旁组织磷酸化蛋白种类分布类似。结论:胆管细胞癌组织中酪氨酸激酶激活,DDR1、EPHA2、EGFR和ROS1酪氨酸激酶活性比癌旁组织高表达,可能致胆管细胞癌的发生。     

食管鳞状细胞癌组织中酪氨酸激酶受体B和脑源性神经生长因子蛋白及mRNA的表达及意义

目的 探讨酪氨酸激酶受体B( TrkB)和脑源性神经生长因子(BDNF)蛋白及mRNA在食管鳞状细胞癌(ESCC)组织中的表达及其意义.方法 应用免疫组织化学及原位杂交法检测59例ESCC、27例癌旁不典型增生组织及36例正常食管黏膜组织中TrkB和BDNF蛋白及mRNA的表达.结果 ESCC组织中TrkB蛋白及mRNA的阳性表达率分别为71.2％和64.4％,显著高于癌旁不典型增生组织(阳性率分别为48.1％和33.3％)及正常食管黏膜组织(阳性率均为0.0％),组间比较差异有统计学意义(P＜0.05);此外,BDNF蛋白和mRNA在ESCC组织中的阳性表达率分别为76.3％和69.5％,也显著高于癌旁不典型增生组织(阳性率分别为55.6％和40.7％)及正常食管黏膜组织(阳性率均为0.0％),组间比较差异有统计学意义(P＜0.05).TrkB和BDNF蛋白及mRNA的表达均与ESCC的分化程度、浸润深度和淋巴结转移密切相关(P＜0.05).进一步相关分析结果显示,TrkB mRNA和蛋白的表达均与BDNF mRNA和蛋白的表达呈正相关(P＜0.05).结论 TrkB和BDNF蛋白及mRNA表达与ESCC的发生、发展和转移密切相关.     

食管鳞状细胞癌EMMPRIN蛋白的表达及临床意义

目的 探讨食管鳞状细胞癌（ESCC）中细胞外基质金属蛋白酶诱导因子（EMMPRIN）蛋白的表达及临床意义。方法 免疫组织化学染色法检测85例ESCC、18例癌旁不典型增生（AH）、38例癌旁“正常”鳞状上皮（NSEBC）和15例正常食管鳞状上皮（NSE）中EMMPRIN蛋白的表达。结果ESCC、AH、NSEBC和NSE中EMMPRIN蛋白的阳性率分别为80％（68／85）、39％（7／18）、66％（25／38）和20％（3／15）；ESCC中EMMPRIN蛋白阳性率高于非癌肿组织（P＜0．01，r=0．35）且阳性细胞分布区域不同；高、中度分化组ESCC中EMMPRIN蛋白阳性率高于低分化组（P＜0．01，r=0．29）；ESCC中EMMPRIN蛋白的表达与肿瘤浸润食管壁的深度、临床分期和淋巴结转移均无明显相关（P＞0．05）。结论 EMMPRIN蛋白在ESCC组织的表达与在非癌肿组织的表达存在显著不同，且它与癌肿的组织分化程度有密切关系。     

Polo样激酶1和细胞分裂周期蛋白20表达及其与食管鳞状细胞癌生物学行为的关系

目的:探讨Polo样激酶1(PLK1)和细胞分裂周期分子20(CDC20)与食管鳞状细胞癌(ESCC)生物学行为的关系。方法:收集2016年2月至2020年10月诸城市人民医院、解放军第九七○医院和菏泽牡丹人民医院(菏泽市中心医院)病理确诊的65例ESCC患者的癌组织和对应癌旁组织标本,采用免疫组织化学法检测PLK1蛋...     

细胞分裂周期蛋白42mRNA和蛋白在食管鳞癌中的表达及其病理生物学意义

目的 探讨细胞分裂周期蛋白42(Cdc42)在食管鳞状细胞癌(ESCC)中的表达及其与临床病理参数间的关系.方法 应用实时荧光定量-聚合酶链反应(qRT-PCR)、蛋白免疫印迹和免疫组织化学方法,从mRNA和蛋白两个水平检测ESCC中Cdc42的表达,并分析其与临床病理参数的关系.结果 22对新鲜ESCC与癌旁正常组织中,Cdc42 mRNA在ESCC中的表达量(0.21±0.14)显著高于其在癌旁正常组织中(0.16±0.12)的表达(P＜0.05);Cdc42蛋白在ESCC中的表达量(0.83±0.35)高于其在癌旁正常组织中(0.75±0.24)的表达;在175对ESCC中,Cdc42蛋白的阳性表达率为73.7%(129/175),高于其在配对的癌旁正常组织中的表达62.9%(110/175,P＜0.05).此外,Cdc42的表达与ESCC患者的年龄、淋巴结转移及分化程度明显相关(P＜0.05).结论 Cdc42可能参与ESCC发生及转移的过程.

Abstract：

Objective To explore the expression of cell division cycle 42 (Cdc42) in human esophageal squamous cell carcinoma (ESCC) and investigate the association between Cdc42 and clinicopathological parameters. Methods The expression levels of Cdc42 mRNA and protein in ESCC and corresponding adjacent normal tissues were detected by real-time fluorescent quantitative polymerase chain reaction ( qRT-PCR), Western blotting and immunohistochemistry, respectively. The correlations between Cdc42 expression and clinicopathological parameters were analyzed. Results The expression of Cdc42 mRNA was significantly higher in ESCC tissues (0. 21 ± 0. 14 ) than that in corresponding controls (0. 16 ±0. 12) (t test,P ＜0. 05). The protein expression of Cdc42 was significantly higher in ESCC tissues (0. 83 ± 0. 35 ) than that in corresponding controls ( 0. 75 ± 0. 24). Immunohistochemistry revealed that 73.7% (129/175) of the ESCC samples had higher expression of Cdc42 protein than the corresponding controls[62. 9% (110/175) (χ2 test, P ＜ 0. 05 )]. Cdc42 expression level was correlated with age,lymphoid node metastasis and differentiation ( P all ＜ 0. 05 ), but not with the clinicopathological features,such as gender, ethnicity and macroscopical types (P ＞ 0. 05 ). Conclusion The higher expression of Cdc42 played a certain role in the carcinogenesis and metastasis of ESCC.     

Cbp recruitment of Csk into lipid rafts is critical to c‐Src kinase activity and bone resorption in osteoclasts

A tyrosine kinase, c‐Src, that plays an indispensable role in ruffled border formation and bone resorption is constitutively active in osteoclasts. However, to date, the molecular mechanism underlying increased c‐Src activity in osteoclasts is unknown. To address this, we first examined the expression levels and subcellular localization of Csk, a negative regulatory kinase for c‐Src. We found that the expression level of Csk in osteoclasts was comparable with that of other tissues. However, in osteoclasts, Csk was hardly localized in lipid rafts, where c‐Src is highly expressed. Interestingly, expression of Cbp, which recruits Csk into lipid rafts through physical interaction with Csk, was very low in osteoclasts compared with other tissues. To understand the importance of Cbp in osteoclasts, we introduced Cbp into osteoclasts using an adenovirus gene delivery system. Introduction of Cbp stimulated recruitment of Csk into lipid rafts and suppressed c‐Src activity in a dose‐dependent manner. Furthermore, introduction of Cbp markedly inhibited formation of actin rings and bone‐resorbing activity in osteoclasts. In addition, treatment with RANKL and overexpression of TRAF6 or NFAT2 inhibited Cbp expression in the osteoclastogenic cell line RAW264.7 along with osteoclastic differentiation. NFAT2 overexpression also inhibited Cbp expression in spleen macrophages. Collectively, our results indicate that reduction in Cbp expression is responsible for maintaining high c‐Src activity in osteoclasts. These findings contribute to an understanding of the unique regulatory system for c‐Src in osteoclasts. © 2010 American Society for Bone and Mineral Research     

Src as a therapeutic target in men with prostate cancer and bone metastases

While responsive to androgen ablation in its early stages, prostate cancer eventually becomes castration‐resistant and metastasizes preferentially to bone. Once this happens, the disease carries considerable morbidity and is incurable. The process of bone metastasis involves a complex interplay between tumour and bone tissue. The eventual characteristic clinical presentation of disorganized osteoblastic bone lesions is preceded by a facilitatory osteoblastic phase; an osteoblastic component then continues to underlie the process. Increasing evidence has shown a ubiquitous role for Src (a proto‐oncogene tyrosine‐protein kinase) in multiple tumour and bone‐signalling processes involved in prostate tumour progression, driving proliferation, survival, migration and transition to androgen‐independent growth. It is also intimately involved in positively regulating osteoclast physiology. As such, this molecule represents an attractive target for managing progressing prostate cancer. Encouraging results have been obtained in preclinical and clinical studies using Src inhibitors like AZD0530 and dasatinib. Both compounds reduced markers of bone resorption, in patients with cancer and those with advanced castration‐resistant prostate cancer, respectively. Moreover, because Src is central to many mechanisms thought to be responsible for the development of castration resistance, adding Src inhibitors to a treatment regimen might reverse this phenomenon. As a result, many Src inhibitors are in preclinical development. This review explores Src inhibition as a strategy for managing bone metastasis in prostate cancer, with a particular focus on targeting the critical osteoclastic response. Other emerging and novel approaches are also considered.     

Osteopontin Expression in Squamous Cell Cancer of the Esophagus

BACKGROUND: The purpose of this study was to better understand the role of osteopontin (OPN) in esophageal squamous cell carcinoma (ESCC) by comparing the OPN mRNA level in ESCC tumor tissue and matched normal tissue and by determining the prognostic significance of the gene expression. METHODS: Initially, by an oligo-nucleotide microarray hybridization technique, OPN expressions were found to consistently elevate at least twofold in three ESCC tissues compared with their adjacent normal ones. Subsequently, the expression of OPN mRNA was detected by real-time QRT-PCR among the 58 fresh surgical ESCC specimens. The clinical information was obtained by chart review. RESULTS: OPN mRNA expression was detectable in 58 of 58 (100%) tumor specimens and 57 of 58 (98.3%) nonmalignant esophageal specimens. OPN expression was higher in tumor tissue than in the matched normal tissue in 54 of 58 (93.1%) individual cases. The overall median mRNA expression level of OPN was approximately 8.8-fold higher in tumor tissues (4.1; range: 0.02-247) compared with matched normal esophageal tissues (0.5; range, 0.0-21.4; p < 0.001). Overexpression of OPN mRNA was significantly associated with clinical stage (p = 0.01). The more severe the clinical stage (from I-II, III, to IV) was the higher frequency of overexpression of OPN mRNA. No significant associations were found between overexpression of OPN mRNA and the patients' survival (p = 0.27). DISCUSSION: Our findings suggest OPN is associated with esophageal tumorigenesis and progression, but not patients' survival.     

A novel inhibitor of the tyrosine kinase Src suppresses phosphorylation of its major cellular substrates and reduces bone resorption in vitro and in rodent models in vivo.

The tyrosine kinase Src has been implicated in the process of osteoclast-mediated bone resorption. Here, we describe a novel class of Src inhibitors, substituted 5,7-diphenyl-pyrrolo[2,3-d]pyrimidines, and characterize one of them, CGP77675, in vitro and in models of bone resorption in vivo. In vitro, CGP77675 inhibited phosphorylation of peptide substrates and autophosphorylation of purified Src (concentration producing half-maximal inhibition [IC50] values 5-20 and 40 nmol/L, respectively). The compound was selective toward other protein kinases: the Src IC50 value was lower than those for Cdc2 (>500-fold), epidermal growth factor (EGF) receptor (7.5-fold), and vascular endothelial growth factor receptor (>50-fold), and for v-Abl (15-fold) and focal adhesion kinase (Fak) (>25-fold). The Src kinase family members Lck and Yes were inhibited with IC50 values 20-fold higher than or equal to Src. To measure the inhibition of cellular Src activity, we identified the major tyrosine-phosphorylated proteins in an Src-overexpressing cell line IC8.1 as Src, Fak, and paxillin. CGP77675 potently inhibited tyrosine phosphorylation of the Src substrates Fak and paxillin, but had much less effect on Src (IC50 values 0.3, 0.5, and 5.7 micromol/L). The phosphorylation of Src in IC8.1 cells reflected phosphorylation of the negative regulatory tyrosine 527 (Y527); thus, the inhibitor was selective against the Y527 C-terminal Src kinase Csk. In osteoblastic MC3T3-E1 cells, CGP77675 inhibited signaling induced by PDGF at the receptor level, but not signaling by EGF, basic fibroblast growth factor, insulin-like growth factor-1, and phorbol 12-myristate 13-acetate. The effect of CGP77675 on bone resorption was evaluated in vitro and in vivo. The parathyroid hormone-induced bone resorption in rat fetal long bone cultures was inhibited with an IC50 of 0.8 micromol/L. CGP77675 dose-dependently reduced the hypercalcemia induced in mice by interleukin-1beta and partly prevented bone loss and microarchitectural changes in young ovariectomized rats, showing that the protective effect on bone was exerted via the inhibition of bone resorption. Thus, specific Src family kinase inhibitors may be useful for the treatment of diseases associated with elevated bone loss.     

Ischemia reperfusion-induced dynamic changes of protein tyrosine phosphorylation during human lung transplantation

BACKGROUND: We have recently demonstrated that more than 20% of lung cells undergo apoptosis within the first 2 hr of graft reperfusion after human lung transplantation. It has been found that changes of protein tyrosine phosphorylation are involved in the regulation of apoptosis in various cell types. METHODS: To determine the protein tyrosine phosphorylation status and related biochemistry changes, lung tissue biopsies were collected from six human lung transplant procedures after cold ischemic preservation (2-5 hr at 4 degrees C), after completing the implantation procedure (approximately 1 hr), and 1 or 2 hr after graft reperfusion. Western blotting was performed to determine protein tyrosine phosphorylation and several signal transduction proteins. Protein tyrosine kinase (PTK) and protein tyrosine phosphatase (PTP) activities were also measured. RESULTS: Protein tyrosine phosphorylation was significantly increased after lung implantation and before reperfusion, and significantly decreased during the first 2 hr of graft reperfusion. The activity of Src PTKs was reduced by 50% during graft reperfusion, which was associated with a decrease of Src proteins and human actin filament associated protein, a cofactor for Src activation. PTP activity significantly decreased after lung implantation and remained at a low level 1 hr after reperfusion. After 2 hr of reperfusion, however, PTP activity returned to the basal level. CONCLUSION: These dynamic changes of PTK and PTP likely explain the observed alterations of protein tyrosine phosphorylation. The significant decrease in protein tyrosine phosphorylation may be related to the observed apoptotic cell death during human lung transplantation.     

Inhibition of Src tyrosine kinase and effect on outcomes in a new in vivo model of surgically induced brain injury

OBJECT: Brain tissue at the periphery of a neurosurgical resection site is vulnerable to injury by a variety of mechanisms including direct trauma, edema, hemorrhage, retractor stretch, and electrocautery. The goal in the present study was to develop an in vivo model of surgically induced brain injury and to test an Src tyrosine kinase inhibitor for neuroprotective properties in this model. METHODS: The authors developed a new surgically induced brain injury model in rats. This model involves resection of part of the frontal lobe. Sprague-Dawley male rats weighing between 300 and 350 g were divided randomly into four groups: Group 1, surgical injury with vehicle treatment; Group 2, surgical injury after treatment with PP1 (an Src tyrosine kinase inhibitor with known neuroprotective properties); Group 3, sham surgery; and Group 4, control. Postoperative assessment included blood-brain barrier (BBB) permeability studies, and histological, immunohistochemical, and Western blot analyses. The authors found that surgical injury caused localized edema and disruption of the BBB compared with findings in the sham surgery group. Treatment with PP1 was associated with decreased edema, decreased breakdown of the BBB, decreased expression of both vascular endothelial growth factor and phosphorylated extracellular signal-regulated kinase 1 and 2, and preservation of ZO-1 expression. CONCLUSIONS: In this study the authors describe a simple and reproducible in vivo animal model of surgically induced brain injury. Pretreatment with PP1 results in improved outcomes in this model, which suggests a possible role for Src tyrosine kinase inhibitors as preoperative therapy for planned neurosurgical procedures.     

Ischemia-reperfusion decreases protein tyrosine phosphorylation and p38 mitogen-activated protein kinase phosphorylation in rat lung transplants.

BACKGROUND: Dramatic alterations of protein tyrosine phosphorylation have been found during the ischemia-reperfusion (IR) period of human lung transplantation. IR also induces activation of p38 mitogen-activated protein kinase (p38) in the heart and kidney. The objective of the present study was to determine whether these changes exist in a rat single-lung transplant model for further mechanistic investigations. METHODS: Isogeneic lung transplantation was performed from Lewis (LEW) to LEW rats, whereas allogeneic transplantation was from LEW to Brown Norway (BN) rats. Blood gases and peak airway pressure were monitored. Lung tissues were collected after 6 hours of cold ischemic preservation, after 30 minutes of warm ischemia for lung implantation, and after 2 hours of reperfusion. Protein tyrosine kinase (PTK) and phosphatase (PTP) activities were measured. Protein tyrosine phosphorylation, Src PTK and p38 expression and p38 phosphorylation were examined by western blotting. RESULTS: In both iso- and allografts, the lung function of transplants was very well preserved. Protein tyrosine phosphorylation, PTK and PTP activities were decreased significantly after 2 hours of reperfusion. Src protein level and phosphorylation of p38 were reduced after 2 hours of reperfusion. CONCLUSIONS: During the early IR period of lung transplantation, decreased protein tyrosine phosphorylation may be involved in apoptosis and other biologic changes. The lack of p38 activation suggests that activity of mitogen-activated protein kinase pathways in the lung transplantation setting may be different from other IR processes.     

Contribution of Src tyrosine kinase to cerebral vasospasm after subarachnoid hemorrhage

OBJECT: Mitogen-activated protein kinase (MAPK) has been implicated in cerebral vasospasm after subarachnoid hemorrhage (SAH). This study was conducted to investigate whether Src tyrosine kinase, an upstream regulator of MAPK, is involved in cerebral vasospasm. METHODS: An established canine double-hemorrhage model was used. Twenty-four dogs were divided into four groups: control, vehicle-treated, Src inhibitor PP2-treated, and Src inhibitor damnacanthal-treated groups. Vehicle (dimethyl sulfoxide), PP2, or damnacanthal was injected daily into the cisterna magna of 18 dogs at 3 to 6 days after induction of SAH. Angiography was performed on Day 0 (the day on which the first blood injection was administered to induce SAH) and on Day 7. Western blot analysis of Src and MAPK activation in basilar arteries (BAs) collected on Day 7 post-SAH was performed. Severe vasospasm was observed in the BAs of vehicle-treated dogs. Mild vasospasm was observed in all dogs treated with Src inhibitors. Phosphorylated Src and MAPK were increased after SAH and activation of these kinases in the BAs was abolished by PP2 and damnacanthal. CONCLUSIONS: The tyrosine kinase Src is an important upstream regulator of MAPK, and inhibition of Src might offer a new therapy in the management of cerebral vasospasm.