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Hypoxia-inducible factor 1alpha and vascular endothelial growth factor in Glioblastoma Multiforme:a systematic review going beyond pathologic implications
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作者 DIMITRA P.VAGELI PANAGIOTIS G.DOUKAS +5 位作者 KERASIA GOUPOU ANTONIOS D.BENOS KYRIAKI ASTARA KONSTANTINA ZACHAROULI SOTIRIS SOTIRIOU MARIA IOANNOU 《Oncology Research》 SCIE 2024年第8期1239-1256,共18页
Glioblastoma multiforme(GBM)is an aggressive primary brain tumor characterized by extensive heterogeneity and vascular proliferation.Hypoxic conditions in the tissue microenvironment are considered a pivotal player le... Glioblastoma multiforme(GBM)is an aggressive primary brain tumor characterized by extensive heterogeneity and vascular proliferation.Hypoxic conditions in the tissue microenvironment are considered a pivotal player leading tumor progression.Specifically,hypoxia is known to activate inducible factors,such as hypoxia-inducible factor 1alpha(HIF-1α),which in turn can stimulate tumor neo-angiogenesis through activation of various downward mediators,such as the vascular endothelial growth factor(VEGF).Here,we aimed to explore the role of HIF-1α/VEGF immunophenotypes alone and in combination with other prognostic markers or clinical and image analysis data,as potential biomarkers of GBM prognosis and treatment efficacy.We performed a systematic review(Medline/Embase,and Pubmed database search was completed by 16th of April 2024 by two independent teams;PRISMA 2020).We evaluated methods of immunoassays,cell viability,or animal or patient survival methods of the retrieved studies to assess unbiased data.We used inclusion criteria,such as the evaluation of GBM prognosis based on HIF-1α/VEGF expression,other biomarkers or clinical and imaging manifestations in GBM related to HIF-1α/VEGF expression,application of immunoassays for protein expression,and evaluation of the effectiveness of GBM therapeutic strategies based on HIF-1α/VEGF expression.We used exclusion criteria,such as data not reporting both HIF-1αand VEGF or prognosis.We included 50 studies investigating in total 1319 GBM human specimens,18 different cell lines or GBM-derived stem cells,and 6 different animal models,to identify the association of HIF-1α/VEGF immunophenotypes,and with other prognostic factors,clinical and macroscopic data in GBM prognosis and therapeutic approaches.We found that increased HIF-1α/VEGF expression in GBM correlates with oncogenic factors,such as miR-210-3p,Oct4,AKT,COX-2,PDGF-C,PLDO3,M2 polarization,or ALK,leading to unfavorable survival.Reduced HIF-1α/VEGF expression correlates with FIH-1,ADNP,or STAT1 upregulation,as well as with clinical manifestations,like epileptogenicity,and a favorable prognosis of GBM.Based on our data,HIF-1αor VEGF immunophenotypes may be a useful tool to clarify MRI-PET imaging data distinguishing between GBM tumor progression and pseudoprogression.Finally,HIF-1α/VEGF immunophenotypes can reflect GBM treatment efficacy,including combined first-line treatment with histone deacetylase inhibitors,thimerosal,or an active metabolite of irinotecan,as well as STAT3 inhibitors alone,and resulting in a favorable tumor prognosis and patient survival.These data were supported by a combination of variable methods used to evaluate HIF-1α/VEGF immunophenotypes.Data limitations may include the use of less sensitive detection methods in some cases.Overall,our data support HIF-1α/VEGF’s role as biomarkers of GBM prognosis and treatment efficacy. 展开更多
关键词 Glioblastoma multiforme(GBM) Astrocytoma Grade III Astrocytoma Grade IV Hypoxia-inducible factor 1alpha(HIF-1α) Vascular endothelial growth factor(VEGF)
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Transforming growth factor-β1 and vascular endothelial growth factor levels in senile acute myeloid leukemia and correlation with prognosis
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作者 Wan Li Sheng-Yu Ma Hui-Ying Zhao 《World Journal of Clinical Cases》 SCIE 2024年第20期4121-4129,共9页
BACKGROUND Acute myeloid leukemia(AML)is a disease in which immature hematopoietic cells accumulate in the bone marrow and continuously expand,inhibiting hematopoiesis.The treatment and prognosis of this disease have ... BACKGROUND Acute myeloid leukemia(AML)is a disease in which immature hematopoietic cells accumulate in the bone marrow and continuously expand,inhibiting hematopoiesis.The treatment and prognosis of this disease have always been unsatisfactory.AIM To investigate the correlation between vascular endothelial growth factor(VEGF)and transforming growth factor-β1(TGFβ1)expression and prognosis in older adults with AML.METHODS This study enrolled 80 patients with AML(AML group),including 36 with complete response(AML-CR),23 with partial response(AML-PR),and 21 with no response(AML-NR).The expression levels of VEGF and TGFβ1 were detected by reverse transcription polymerase chain reaction in bone marrow mononuclear cells isolated from 56 healthy controls.Kaplan-Meier analysis was performed to assess overall survival(OS)and progression-or disease-free survival(DFS).Prognostic risk factors were analyzed using a Cox proportional hazards model.RESULTS The AML group showed a VEGF level of 2.68±0.16.VEGF expression was lower in patients with AML-CR than those with AML-PR or AML-NR(P<0.05).TGFβ1 expression in the AML group was 0.33±0.05.Patients with AML-CR showed a higher TGFβ1 expression than those with AML-PR or AML-NR(P<0.05).VEGF and TGFβ1 expression in patients with AML was significantly correlated with the counts of leukocytes,platelets,hemoglobin,and peripheral blood immature cells(P<0.05);Kaplan-Meier survival analysis revealed that patients with high TGFβ1 expression had better OS and DFS than those with low TGFβ1 expression(P<0.05),whereas patients with low VEGF levels showed better OS and DFS than those with high VEGF levels(P<0.05).VEGF,TGFβ1,and platelet count were identified by the Cox proportional hazards model as independent risk factors for OS(P<0.05),while VEGF,TGFβ1,and white blood cell count were independent risk factors for DFS(P<0.05).CONCLUSION Decreased VEGF expression and increased TGFβ1 expression in patients with AML provide valuable references for determining and individualizing clinical treatment strategies. 展开更多
关键词 Acute myeloid leukemia Transforming growth factor1 Vascular endothelial growth factor Expression level Prognostic correlation
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Concomitant epidermal growth factor receptor mutation/c-ros oncogene 1 rearrangement in non-small cell lung cancer: A case report
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作者 Gui-Qin Peng Hai-Chi Song Wan-Yi Chen 《World Journal of Clinical Oncology》 2024年第7期945-952,共8页
BACKGROUND Epidermal growth factor receptor(EGFR)mutation and c-ros oncogene 1(ROS1)rearrangement are key genetic alterations and predictive tumor markers for non-small cell lung cancer(NSCLC)and are typically conside... BACKGROUND Epidermal growth factor receptor(EGFR)mutation and c-ros oncogene 1(ROS1)rearrangement are key genetic alterations and predictive tumor markers for non-small cell lung cancer(NSCLC)and are typically considered to be mutually exc-lusive.EGFR/ROS1 co-mutation is a rare event,and the standard treatment appr-oach for such cases is still equivocal.CASE SUMMARY Herein,we report the case of a 64-year-old woman diagnosed with lung adenocar-cinoma,with concomitant EGFR L858R mutation and ROS1 rearrangement.The patient received two cycles of chemotherapy after surgery,but the disease prog-ressed.Following 1-month treatment with gefitinib,the disease progressed again.However,after switching to crizotinib,the lesion became stable.Currently,crizotinib has been administered for over 53 months with a remarkable treatment effect.CONCLUSION The efficacy of EGFR tyrosine kinase inhibitors and crizotinib was vastly different in this NSCLC patient with EGFR/ROS1 co-mutation.This report will aid future treatment of such patients. 展开更多
关键词 Non-small cell lung cancer Epidermal growth factor receptor C-ros oncogene 1 Co-mutation Treatment strategies Case report
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Vascular endothelial growth factor pathway’s influence on bevacizumab efficacy in metastatic colorectal cancer treatment
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作者 Yuan Qin Fu-Yuan Ma +2 位作者 Zhi Zhang Chen-Hao Zhao Biao Huang 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第11期4514-4517,共4页
In this article,an article published in the World Journal of Gastrointestinal Oncology,which focuses on whether the expression of programmed death-ligand 1(PD-L1)affects the effectiveness of chemotherapy regimens,incl... In this article,an article published in the World Journal of Gastrointestinal Oncology,which focuses on whether the expression of programmed death-ligand 1(PD-L1)affects the effectiveness of chemotherapy regimens,including bevacizumab,in treating patients with colorectal cancer(CRC).Through neutralization of vascular endothelial growth factor(VEGF),bevacizumab inhibits tumor angiogenesis,impairing neovascularization and thereby depriving the tumor of essential nutrients and oxygen.Conversely,PD-L1 binding to VEGF receptor 2 promotes angiogenesis,supporting tumor vasculature.The interplay between these pathways complicates the assessment of bevacizumab’s efficacy in cancer therapy,notably in CRC,where VEGF and PD-L1 significantly affect treatment response.This review examines metastatic CRC treatment strategies,focusing on bevacizumab’s mechanism of action and the role of PD-L1 in this therapeutic context. 展开更多
关键词 BEVACIZUMAB CHEMOTHERAPY Metastatic colorectal cancer PD-1/PD-L1 axis Therapeutic approach Vascular endothelial growth factor
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Increased serum levels of soluble CD146 and vascular endothelial growth factor receptor 2 in patients with exudative age-related macular degeneration 被引量:5
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作者 Yan-Yao Liu Yue Bin +1 位作者 Xing Wang Hui Peng 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2019年第3期457-463,共7页
AIM: To investigate serum levels of soluble CD146(s CD146) and vascular endothelial growth factor receptor 2(VEGFR2) in patients with age-related macular degeneration(AMD). METHODS: Eighty-eight patients with exudativ... AIM: To investigate serum levels of soluble CD146(s CD146) and vascular endothelial growth factor receptor 2(VEGFR2) in patients with age-related macular degeneration(AMD). METHODS: Eighty-eight patients with exudative AMD and 45 sex-and age-matched healthy controls were enrolled in this study conducted in China. Serum samples was obtained from the patients with exudative AMD and from the controls. Serum sCD146 and VEGFR2 protein levels were measured using an enzyme-linked immunosorbent assay.RESULTS: We found that serum sCD146 and VEGFR2 protein levels were significantly higher in the patients with exudative AMD group than in the controls(t=3.859, P<0.001 and t=3.829, P<0.001, respectively). Serum sCD146 levels were significantly higher in patients with classic choroidal neovascularization(CNV) than in those with occult CNV(t=9.899, P<0.001). There was a significant difference in the trend for exudative AMD in the highest versus lowest quartile of circulating sCD146 levels(χ2=10.29, P=0.001). The receiver operating characteristic curve analysis showed that the area under the curve was 0.696 for s CD146(95%CI: 0.601-0.791) with an optimum diagnostic cut-off value of 157.16 ng/mL, a sensitivity of 55.7%, and a specificity of 82.2%.CONCLUSION: The serum sCD146 level increases and may be a biomarker for exudative AMD. 展开更多
关键词 AGE-RELATED MACULAR DEGENERATION soluble CD146 vascular endothelial growth factor receptor 2 serum
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Human epidermal growth factor receptor 2 expression level and combined positive score can evaluate efficacy of advanced gastric cancer
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作者 Xiao-Ting Ma Kai Ou +2 位作者 Wen-Wei Yang Bi-Yang Cao Lin Yang 《World Journal of Clinical Oncology》 2024年第5期635-643,共9页
BACKGROUND Although treatment options for gastric cancer(GC)continue to advance,the overall prognosis for patients with GC remains poor.At present,the predictors of treatment efficacy remain controversial except for h... BACKGROUND Although treatment options for gastric cancer(GC)continue to advance,the overall prognosis for patients with GC remains poor.At present,the predictors of treatment efficacy remain controversial except for high microsatellite instability.AIM To develop methods to identify groups of patients with GC who would benefit the most from receiving the combination of a programmed cell death protein 1(PD-1)inhibitor and chemotherapy.METHODS We acquired data from 63 patients with human epidermal growth factor receptor 2(HER2)-negative GC with a histological diagnosis of GC at the Cancer Hospital,Chinese Academy of Medical Sciences between November 2020 and October 2022.All of the patients screened received a PD-1 inhibitor combined with chemotherapy as the first-line treatment.RESULTS As of July 1,2023,the objective response rate was 61.9%,and the disease control rate was 96.8%.The median progression-free survival(mPFS)for all patients was 6.3 months.The median overall survival was not achieved.Survival analysis showed that patients with a combined positive score(CPS)≥1 exhibited an extended trend in progression-free survival(PFS)when compared to patients with a CPS of 0 after receiving a PD-1 inhibitor combined with oxaliplatin and tegafur as the first-line treatment.PFS exhibited a trend for prolongation as the expression level of HER2 increased.Based on PFS,we divided patients into two groups:A treatment group with excellent efficacy and a treatment group with poor efficacy.The mPFS of the excellent efficacy group was 8 months,with a mPFS of 9.1 months after excluding a cohort of patients who received interrupted therapy due to surgery.The mPFS was 4.5 months in patients in the group with poor efficacy who did not receive surgery.Using good/poor efficacy as the endpoint of our study,univariate analysis revealed that both CPS score(P=0.004)and HER2 expression level(P=0.015)were both factors that exerted significant influence on the efficacy of treatment the combination of a PD-1 inhibitor and chemotherapy in patients with advanced GC(AGC).Finally,multivariate analysis confirmed that CPS score was a significant influencing factor.CONCLUSION CPS score and HER2 expression both impacted the efficacy of immunotherapy combined with chemotherapy in AGC patients who were non-positive for HER2. 展开更多
关键词 First line Gastric cancer Human epidermal growth factor receptor 2 Programmed cell death protein 1 Progression-free survival
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Exosome-transported IncRNA H19 regulates insulin-like growth factor-1 via the H19/let-7a/insulin-like growth factor-1 receptor axis in ischemic stroke 被引量:3
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作者 Jue Wang Bin Cao +2 位作者 Yan Gao Yu-Hua Chen Juan Feng 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第6期1316-1320,共5页
LncRNA(long non-coding RNA) H19 is a transcript of the H19 gene that is expressed during embryogenesis.We previously discove red a role for circular lncRNA H19 in the onset and prognosis of cerebral ischemic stroke.In... LncRNA(long non-coding RNA) H19 is a transcript of the H19 gene that is expressed during embryogenesis.We previously discove red a role for circular lncRNA H19 in the onset and prognosis of cerebral ischemic stroke.In this study,we used serum from patients with ischemic stroke,and mouse and cell culture models to elucidate the roles of plasma and neuronal exosomes in the regulatory effect of lncRNA H19 on insulin-like growth factor-1 and its mechanism in ischemic stroke,using western blotting,quantitative real-time polymerase chain reaction,and enzyme-linked immunosorbent assays.Plasma exosomal IncRNA H19 was negatively associated with blood levels of insulin-like growth factor-1 in samples from patients with cerebral ischemic stroke.In a mouse model,levels of exosomal IncRNA H19 were positively correlated with plasma and cerebral lncRNA H19.In a cell co-culture model,we confirmed that IncRNA H19 was transported from neuro ns to astrocytes by exosomes to induce downregulation of insulin-like growth factor-1 through the H19/let-7 a/insulin-like growth factor-1 receptor axis.This study provides the first evidence for the transpo rtation of IncRNA H19 by exosomes and the relationship between IncRNA H19 and insulinlike growth factor-1. 展开更多
关键词 cerebral ischemia EXOSOMES H19 insulin-like growth factor-1 insulin-like growth factor 1 receptor ischemic stroke long non-coding RNA
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Expression of vascular endothelial growth factor and its receptors VEGFR-1 and 2 in gastrointestinal stromal tumors,leiomyomas and schwannomas 被引量:9
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作者 Toshiyuki Nakayama Yang Cheul Cho +4 位作者 Yuka Mine Ayumi Yoshizaki Shinji Naito Chun Yang Wen Ichiro Sekine 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第38期6182-6187,共6页
AIM: To investigate the role of vascular endothelial growth factor (VEGF/and its receptors VEGFR-1 and 2 in the growth and differentiation of gastrointestinal strornal tumors (GISTs). METHODS: Thirty-three GISTs,... AIM: To investigate the role of vascular endothelial growth factor (VEGF/and its receptors VEGFR-1 and 2 in the growth and differentiation of gastrointestinal strornal tumors (GISTs). METHODS: Thirty-three GISTs, 15 leiomyomas and 6 schwannomas were examined by immunohistochemistry in this study. RESULTS: VEGF protein was expressed in the cytoplasm of tumor cells, and VEGFRol and 2 were expressed both in the cytoplasm and on the membrane of all tumors. Irnrnunohistochernical staining revealed that 26 GISTs (78.8%), 9 leiornyornas (60.0%) and 3 schwannornas (50.0%/were positive for VEGF; 24 GISTs (72.7%/, 12 leiornyornas (80.0%) and 4 schwannornas (66.7%) were positive for VEGFR-1; 30 GISTs (90.9%/, 5 leiornyornas (33.3%/and 4 schwannornas (66.7%) were positive for VEGFR-2. VEGFR-2 expression was statistically different between GISTs and leiomyomas (P 〈 0.0001). However, there was no correlation between the expression of VEGF pathway componenets and the clinical risk categories. CONCLUSION: Our results suggest that the VEGF pathway may play an important role in the differentiation of GISTs, leiomyomas and schwannomas. 展开更多
关键词 Gastrointestinal stromal tumor LEIOMYOMA SCHWANNOMA Vascular endothelial growth factor Vascular endothelial growth factor receptors
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Prognostic value of vascular endothelial growth factor receptor 1 and classⅢβ-tubulin in survival for nonmetastatic rectal cancer 被引量:4
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作者 Xiang-Quan Kong Yun-Xia Huang +4 位作者 Jin-Luan Li Xue-Qing Zhang Qing-Qin Peng Li-Rui Tang Jun-Xin Wu 《World Journal of Gastrointestinal Oncology》 SCIE CAS 2018年第10期351-359,共9页
AIM To assess the long-term prognostic value of vascular endothelial growth factor receptor 1(VEGFR1)and classⅢβ-tubulin(TUBB3)mRNA expression in nonmetastatic rectal cancer.METHODS A total of 75 consecutive patient... AIM To assess the long-term prognostic value of vascular endothelial growth factor receptor 1(VEGFR1)and classⅢβ-tubulin(TUBB3)mRNA expression in nonmetastatic rectal cancer.METHODS A total of 75 consecutive patients with non-metastatic rectal cancer from March 2004 to November 2008 were analyzed retrospectively at our institute.The mRNA expressions of VEGFR1 and TUBB3 were detected by multiplex branched DNA liquid-chip technology.The Cutoff Finder application was applied to determine cutoff point of mRNA expression.SPSS software version 22.0was used for analysis.RESULTS The median follow-up was 102.7 mo(range,6-153.6).Theχ~2 and Fisher’s exact tests showed that VEGFR1expression was related to lymph node metastasis(P=0.013),while no relationships between TUBB3 and clinicopathological features were observed.Univariate analysis showed that T stage,lymph node metastasis,tumor differentiation,VEGFR1 and TUBB3 mRNA expression were correlated to overall survival(OS)(P=0.048,P=0.003,P=0.052,P=0.003 and P=0.015,respectively).Also,lymph node metastasis and VEGFR1expression independently influenced OS by multivariate analysis(P=0.027 and P=0.033).VEGFR1 expression was positively correlated with TUBB3(P=0.024).The patients with low expression of both TUBB3 and VEGFR1 presented a better OS(P=0.003).In addition,the receiver operating characteristic analysis suggested that the combination of lymph node metastasis and VEGFR1 had a more favorable prognostic value(P<0.001).CONCLUSION VEGFR1 expression and lymph node metastasis independently and jointly affect survival.Moreover,low expression of VEGFR1 and TUBB3 presented a better OS in patients with non-metastatic rectal cancer,which might serve as a potential prognostic factor. 展开更多
关键词 RECTAL cancer ClassⅢβ-tubulin VASCULAR endothelial growth factor receptor 1 Overall SURVIVAL
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Clinicopathological and prognostic significance of galectin-1 and vascular endothelial growth factor expression in gastric cancer 被引量:12
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作者 Jie Chen Su-Jun Zhou +4 位作者 Yun Zhang Guo-Qiang Zhang Tian-Zhou Zha Yi-Zhong Feng Kai Zhang 《World Journal of Gastroenterology》 SCIE CAS 2013年第13期2073-2079,共7页
AIM: To evaluate the expression of galectin-1 and vascular endothelial growth factor (VEGF) in gastric cancer and investigate their relationships with clinicopathologic factors and prognostic significance. METHODS: Ga... AIM: To evaluate the expression of galectin-1 and vascular endothelial growth factor (VEGF) in gastric cancer and investigate their relationships with clinicopathologic factors and prognostic significance. METHODS: Galectin-1 and VEGF were immunohistochemically investigated in tumor samples obtained from 214 gastric cancer patients with all tumor stages. Immunohistochemical analyses for galectin-1 and VEGF expression were performed on formalin-fixed, paraffin-embedded sections of surgical specimens. The relationship between the expression and staining intensity of galectin-1 and VEGF, clinicopathologic variables, and patient survival were analyzed. All patients underwent follow-up until cancer-related death or more than five years after tumor resection. P values < 0.05 were considered statistically significant.RESULTS: Immunohistochemical staining demonstrated that 138 of 214 gastric cancer samples (64.5%) were positive for galectin-1, and 116 out of 214 gastric cancer samples (54.2%) were positive for VEGF. There was a significant association between galectin-1 and VEGF expression; VEGF was detected in 60.1% of galectin-1-positive samples and 43.4% of galectin-1-negative samples (P < 0.05). Galectin-1 expression was associated with tumor size, tumor location, stage, lymph node metastases, and VEGF expression (all P < 0.05). VEGF expression was related to tumor size, stage, and lymph node metastases (all P < 0.05). The 5-year survival rate was 56.6% for galectin-1-positive patients and 69.2% for galectin-1-negative patients, and the prognosis for galectin-1-positive patients was significantly poorer compared with galectin-1-negative patients (χ 2 = 13.880, P = 0.000). The 5-year survival rates for VEGF-positive and VEGF-negative patients were 53.4% and 70.5%, respectively (χ2 = 4.619, P = 0.032). The overall survival rate of patients with both galectin-1 and VEGF overexpression in gastric cancer tissue samples was significantly poorer than other groups (both P < 0.05).CONCLUSION: Galectin-1 expression was positively associated with VEGF expression. Both galectin-1 and VEGF can serve as independent prognostic indicators of poor survival for gastric cancer after gastrectomy. 展开更多
关键词 GALECTIN-1 VASCULAR endothelial growth factor GASTRIC cancer Prognosis
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Streptozotocin induced diabetic retinopathy in rat and the expression of vascular endothelial growth factor and its receptor 被引量:14
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作者 Chen-Yuan Gong Bin Lu +1 位作者 Qian-Wen Hu Li-Li Ji 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2013年第5期573-577,共5页
·AIM: To establishtherat model of streptozotocin (STZ)- induced diabetic retinopathy (DR), which is the most common cause of visual loss and blindness in patients with diabetes, and observe the gene expression of... ·AIM: To establishtherat model of streptozotocin (STZ)- induced diabetic retinopathy (DR), which is the most common cause of visual loss and blindness in patients with diabetes, and observe the gene expression of vascular endothelial growth factor (VEGF) and its receptors during the development of DR. ·METHODS: A rat model of diabetes was established by intraperitoneal injection of STZ. The diabetic rats were housed for 2, 3 and 4 months after the development of diabetes. Retinal histopathological observation was performed. The retinal vessels were observed by immunofluorescence staining by CD31. The mRNA expression of VEGF, VEGF receptor 1 and 2 (VEGFR1/2) in rat retina was detected by reverse transcription - polymerase chain reaction (RT-PCR) analysis. · RESULTS: Retinal histopathological observation showed the morphological changes of inner nuclear layer (INL) and outer nuclear layer (ONL) at any time -point, and also demonstrated the increased new vessels at both 3, 4 months after the development of diabetes. The CD31 staining results showed that the number of vessels was increased in the retinas of diabetic rats at both 3 and 4 months after the development of diabetes. As compared to the normal rats, the mRNA expression of VEGF was increased in retinas of diabetic rats at 3 months after the development of diabetes, while VEGFR1 and VEGFR2 mRNA expression was increased at 2, 3 and 4 months after the development of diabetes.·CONCLUSION:Takentogether,ourresultsdemonstrated that DR was occurred at 3 months after the development of diabetes, and the mRNA expression of VEGF, VEGFR1 and VEGFR2 were increased in the process of DR. The present study further evidenced the involvement of VEGF and its receptors in the process of DR. · 展开更多
关键词 diabetic retinopathy vascular endothelial growth factor vascular endothelial growth factor receptor
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Early expressions of hypoxia-inducible factor 1alpha and vascular endothelial growth factor increase the neuronal plasticity of activated endogenous neural stem cells after focal cerebral ischemia 被引量:18
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作者 Seung Song Jong-Tae Park +4 位作者 Joo Young Na Man-Seok Park Jeong-Kil Lee Min-Cheol Lee Hyung-Seok Kim 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第9期912-918,共7页
Endogenous neural stem cells become "activated" after neuronal injury, but the activation sequence and fate of endogenous neural stem cells in focal cerebral ischemia model are little known. We evaluated the relatio... Endogenous neural stem cells become "activated" after neuronal injury, but the activation sequence and fate of endogenous neural stem cells in focal cerebral ischemia model are little known. We evaluated the relationships between neural stem cells and hypoxia-inducible factor-1α and vascular endothelial growth factor expression in a photothromobotic rat stroke model using immunohistochemistry and western blot analysis. We also evaluated the chronological changes of neural stem cells by 5-bromo-2′-deoxyuridine(BrdU) incorporation. Hypoxia-inducible factor-1α expression was initially increased from 1 hour after ischemic injury, followed by vascular endothelial growth factor expression. Hypoxia-inducible factor-1α immunoreactivity was detected in the ipsilateral cortical neurons of the infarct core and peri-infarct area. Vascular endothelial growth factor immunoreactivity was detected in bilateral cortex, but ipsilateral cortex staining intensity and numbers were greater than the contralateral cortex. Vascular endothelial growth factor immunoreactive cells were easily found along the peri-infarct area 12 hours after focal cerebral ischemia. The expression of nestin increased throughout the microvasculature in the ischemic core and the peri-infarct area in all experimental rats after 24 hours of ischemic injury. Nestin immunoreactivity increased in the subventricular zone during 12 hours to 3 days, and prominently increased in the ipsilateral cortex between 3–7 days. Nestin-labeled cells showed dual differentiation with microvessels near the infarct core and reactive astrocytes in the peri-infarct area. BrdU-labeled cells were increased gradually from day 1 in the ipsilateral subventricular zone and cortex, and numerous BrdU-labeled cells were observed in the peri-infarct area and non-lesioned cortex at 3 days. BrdU-labeled cells rather than neurons, were mainly co-labeled with nestin and GFAP. Early expressions of hypoxia-inducible factor-1α and vascular endothelial growth factor after ischemia made up the microenvironment to increase the neuronal plasticity of activated endogenous neural stem cells. Moreover, neural precursor cells after large-scale cortical injury could be recruited from the cortex nearby infarct core and subventricular zone. 展开更多
关键词 nerve regeneration brain ischemia neural stem cell neural precursor cell hypoxia-inducible factor 1α vascular endothelial growth factor MICROENVIRONMENT PHOTOTHROMBOSIS neural regeneration
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Vascular endothelial growth factor A, secreted in response to transforming growth factor-β1 under hypoxic conditions, induces autocrine effects on migration of prostate cancer cells 被引量:20
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作者 Eric Darrington Miao Zhong Bao-Han Vo Shafiq A Khan 《Asian Journal of Andrology》 SCIE CAS CSCD 2012年第5期745-751,共7页
Hypoxia and transforming growth factor-β1 (TGF-β1) increase vascular endothelial growth factor A (VEGFA) expression in a number of malignancies. This effect of hypoxia and TGF-β1 might be responsible for tumor ... Hypoxia and transforming growth factor-β1 (TGF-β1) increase vascular endothelial growth factor A (VEGFA) expression in a number of malignancies. This effect of hypoxia and TGF-β1 might be responsible for tumor progression and metastasis of advanced prostate cancer. In the present study, TGF-β1 was shown to induce VEGFA165 secretion from both normal cell lines (HPV7 and RWPE1) and prostate cancer cell lines (DU 145 and PC3). Conversely, hypoxia-stimulated VEGFA165 secretion was observed only in prostate cancer cell lines. Hypoxia induced TGF-β1 expression in PC3 prostate cancer cells, and the TGF-β1 type I receptor (ALK5) kinase inhibitor partially blocked hypoxia-mediated VEGFA16s secretion. This effect of hypoxia provides a novel mechanism to increase VEGFA expression in prostate cancer cells. Although autocrine signaling of VEGFA has been implicated in prostate cancer progression and metastasis, the associated mechanism is poorly characterized. VEGFA activity is mediated via VEGF receptor (VEGFR) 1 (Fit-l) and 2 (FIk-I/KDR). Whereas VEGFR-1 mRNA was detected in normal prostate epithelial cells, VEGFR-2 mRNA and VEGFR protein were expressed only in PC3 cells. VEGFA165 treatment induced phosphorylation of extracellular signal-regulated kinase 1/2 (ERKI/2) in PC3 cells but not in HPV7 cells, suggesting that the autocrine function of VEGFA may be uniquely associated with prostate cancer. Activation of VEGFR-2 by VEGFA165 was shown to enhance migration of PC3 cells. A similar effect was also observed with endogenous VEGFA induced by TGF-β1 and hypoxia. These findings illustrate that an autocrine loop of VEGFA via VEGFR-2 is critical for the tumorigenic effects of TGF-β1 and hypoxia on metastatic prostate cancers. 展开更多
关键词 cell migration HYPOXIA prostate cancer transforming growth factor1 (TGF-β1 vascular endothelial growth factor A(VEGFA)
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Molecular Modeling Studies of Vascular Endothelial Growth Factor Receptor Tyrosine Kinase Inhibitors Combining Molecular Docking and 3D-QSAR Methods 被引量:8
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作者 路亚阔 王娟 +2 位作者 胡勇 林勇 林治华 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2013年第5期679-694,共16页
The vascular endothelial growth factor (VEGF) and its receptor tyrosine kinases VEGFR-2 or kinase insertdomain receptor (KDR) have emerged as attractive targets for the design of novel anticancer agents. In the pr... The vascular endothelial growth factor (VEGF) and its receptor tyrosine kinases VEGFR-2 or kinase insertdomain receptor (KDR) have emerged as attractive targets for the design of novel anticancer agents. In the present work, molecular docking method combined with three dimensional quantitative structure-activity relationships (comparative molecular field analysis (CoMFA) and comparative molecular similarity indice analysis (CoMSIA)) to analyze the possible interactions between KDR and those derivatives which acted as selective inhibitors. The CoMFA and CoMSIA models gave a cross-validated coefficient Q2 of 0.713 and 0.549, non-cross-validated R2 values of 0.974 and 0.878, and predicted R2 values of 0.966 and 0.823, respectively. The 3D contour maps generated by the CoMFA and CoMSIA models were used to identify the key structural requirements responsible for the biological activity. The information obtained from 3D-QSAR and docking studies were very helpful to design novel selective inhibitors of KDR with desired activity and good chemical property. 展开更多
关键词 vascular endothelial growth factor receptor 2 (VEGFR-2) KDR inhibitor COMFA COMSIA molecular docking
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Expression of thymidine kinase mediated by a novel non-viral delivery system under the control of vascular endothelial growth factor receptor 2 promoter selectively kills human umbilical vein endothelial cells 被引量:9
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作者 Ying Wang Hui-Xiong Xu +1 位作者 Ming-De Lu Qing Tang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第2期224-230,共7页
AIM: To investigate the killing efficiency of a recombinant plasmid containing a thymidine kinase (TK) domain insert driven by the vascular endothelial growth factor receptor 2 (VEGFR2) promoter (KDR) on vascular endo... AIM: To investigate the killing efficiency of a recombinant plasmid containing a thymidine kinase (TK) domain insert driven by the vascular endothelial growth factor receptor 2 (VEGFR2) promoter (KDR) on vascular endothelial cells.METHODS: The KDR-TK fragment was extracted from pBluescript Ⅱ KDR-TK plasmid by enzymatic digestion with Xho I and Sal I. The enhanced green fluorescence protein (EGFP) carrier was extracted from pEGFP by the same procedure. The KDR-TK was inserted into the pEGFP carrier to construct pEGFP-KDR-TK. Using ultrasound irradiation and microbubble, pEGFP-KDR-TK was transferred into human umbilical vein endothelial cells (HUVECs). The transient infection rate was estimated by green fluorescent protein (GFP) expression. Transfected HUVECs, non-transfected HUVECs, and HepG2 cells were cultured in the presence of different concentrations of ganciclovir (GCV), and the killing efficacy of HSV-TK/GCV was analyzed by 3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyl tetrazolium bromide (MTT) assay. RESULTS: The recombinant pEGFP-KDR-TK was successfully constructed by inserting the KDR-TK fragment into the pEGFP carrier. Transfected HUVECs showed cytoplasmic green fluorescence, and the transient transfection rate was about 20.3%. Pools of G418-resistant cells exhibited a higher sensitivity to theprodrug/GCV compared to non-transfected HUVECs or non-transfected HepG2 cells, respectively. CONCLUSION: KDR promoter and the suicide gene/prodrug system mediated by diagnostic ultrasound combined with microbubble can significantly kill HUVECs. Such therapy may present a novel and attractive approach to target gene therapy on tumor vessels. 展开更多
关键词 MICROBUBBLE ULTRASOUND Gene therapy Vascular endothelial growth factor receptor 2 Humanumbilical vein endothelial cells
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STI571 (Glivec) suppresses the expression of vascular endothelial growth factor in the gastrointestinal stromal tumor cell line,GIST-T1 被引量:14
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作者 Toufeng Jin Hajime Nakatani +5 位作者 Takahiro Taguchi Takumi Nakano Takehiro Okabayashi Takeki Sugimoto Michiya Kobayashi Keijiro Araki 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第5期703-708,共6页
AIM: To estimate whether S-TI571 inhibits the expression of vascular endothelial growth factor (VEGF) in the gastrointestinal stromal tumor (GIST) cells. METHODS: We used GIST cell line, GIST-T1. It has a hetero... AIM: To estimate whether S-TI571 inhibits the expression of vascular endothelial growth factor (VEGF) in the gastrointestinal stromal tumor (GIST) cells. METHODS: We used GIST cell line, GIST-T1. It has a heterogenic 57-bp deletion in exon 11 to produce a mutated c-KIT, which results in constitutive activation of c-KIT. Cells were treated with/without STI571 or stem cell factor (SCF). Transcription and expression of VEGF were determined by RT-PCR and flow cytometry or Western blotting, respectively. Activated c-KIT was estimated by immunoprecipitation analysis. Cell viability was determined by PITT assay. RESULTS: Activation of c-KIT was inhibited by STI571 treatment. VEGF was suppressed at both the transcriptional and translational levels in a temporal and dose-dependent manner by STI571. SCF upregulated the expression of VEGF and it was inhibited by S-13571. STI571 also reduced the cell viability of the GIST-T1 cells, as determined by PTT assay. CONCLUSION: Activation of c-KIT in the GIST-T1 regulated the expression of VEGF and it was inhibited by ST571. STI571 has antitumor effects on the GIST cells with respect to not only the inhibition of cell growth, but also the suppression of VEGF expression. 展开更多
关键词 C-KIT Vascular endothelial growth factor(VEGF) S-13571 Gastrointestinal stromal tumor GIST-T1
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Emodin regulating excision repair cross-complementation group 1 through fibroblast growth factor receptor 2 signaling 被引量:3
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作者 Gang Chen Hong Qiu +3 位作者 Shan-Dong Ke Shao-Ming Hu Shi-Ying Yu Sheng-Quan Zou 《World Journal of Gastroenterology》 SCIE CAS 2013年第16期2481-2491,共11页
AIM: To investigate the molecular mechanisms underlying the reversal effect of emodin on platinum resistance in hepatocellular carcinoma. METHODS: After the addition of 10 μmol/L emodin to HepG2/oxaliplatin (OXA) cel... AIM: To investigate the molecular mechanisms underlying the reversal effect of emodin on platinum resistance in hepatocellular carcinoma. METHODS: After the addition of 10 μmol/L emodin to HepG2/oxaliplatin (OXA) cells, the inhibition rate (IR), 50% inhibitory concentration (IC 50 ) and reversal index (IC 50 in experimental group/IC 50 in control group) were calculated. For HepG2, HepG2/OXA, HepG2/OXA/T, each cell line was divided into a control group, OXA group, OXA + fibroblast growth factor 7 (FGF7) group and OXA + emodin group, and the final concentrations of FGF7, emodin and OXA in each group were 5 ng/mL, 10 μg/mL and 10 μmol/L, respectively. Single-cell gel electrophoresis was conducted to detect DNA damage, and the fibroblast growth factor receptor 2 (FGFR2), phosphorylated extracellular signal-regulated kinase 1/2 (p-ERK1/2) and excision repair cross-complementing gene 1 (ERCC1) protein expression levels in each group were examined by Western blotting. RESULTS: Compared with the IC50 of 120.78 μmol/L in HepG2/OXA cells, the IC 50 decreased to 39.65 μmol/L after treatment with 10 μmol/L emodin; thus, the reversal index was 3.05. Compared with the control group, the tail length and Olive tail length in the OXA group, OXA + FGF7 group and OXA + emodin group were significantly increased, and the differences were statistically significant (P < 0.01). The tail length and Olive tail length were lower in the OXA + FGF7 group than in the OXA group, and this difference was also statistically significant. Compared with the OXA + FGF7 group, the tail extent, the Olive tail moment and the percentage of tail DNA were significantly increased in the OXA + emodin group, and these differences were statistically significant (P < 0.01). In comparison with its parental cell line HepG2, the HepG2/OXA cells demonstrated significantly increased FGFR2, p-ERK1/2 and ERCC1 expression levels, whereas the expression of all three molecules was significantly inhibited in HepG2/ OXA/T cells, in which FGFR2 was silenced by FGFR2 shRNA. In the examined HepG2 cells, the FGFR2, p-ERK1/2 and ERCC1 expression levels demonstrated increasing trends in the OXA group and OXA + FGF7 group. Compared with the OXA group and OXA + FGF7 group, the FGFR2, p-ERK1/2, and ERCC1 expression levels were significantly lower in the OXA + emodin group, and these differences were statistically significant. In the HepG2/OXA/T cell line that was transfected with FGFR2 shRNA, the FGFR2, p-ERK1/2 and ERCC1 expression levels were significantly inhibited, but there were no significant differences in these expression levels among the OXA, OXA + FGF7 and OXA + emodin groups. CONCLUSION: Emodin markedly reversed OXA resistance by enhancing OXA DNA damage in HepG2/OXA cells, and the molecular mechanism was related to the inhibitory effect on ERCC1 expression being mediated by the FGFR2/ERK1/2 signaling pathway. 展开更多
关键词 HEPATOCELLULAR carcinoma EMODIN FIBROBLAST growth factor receptor 2 EXCISION repair crosscomplementation group 1 Platinum resistance EXTRACELLULAR SIGNAL-REGULATED kinase
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Interleukin-1α, 6 regulate the secretion of vascular endothelial growth factor A, C in pancreatic cancer 被引量:6
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作者 Department of Hepatobiliary Surgery (Tang RF, Zhang FR, Peng L, Wang SX, Xiao Y and Zhang M) and Department of Dermatology (Wang SX), 4th Hospital, Hebei Medical University, Shijiazhuang 050011, China 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2005年第3期460-463,共4页
Vascular endothelial growth factor (VEGF, namely VEGF-A) is an angiogenic polypeptide and VEGF-C is a lymphangiogenic polypeptide that has been implicated in cancer growth, invasion and metastasis. Several cytokines a... Vascular endothelial growth factor (VEGF, namely VEGF-A) is an angiogenic polypeptide and VEGF-C is a lymphangiogenic polypeptide that has been implicated in cancer growth, invasion and metastasis. Several cytokines and growth factors play an important part in cancer progression. These cytokines and growth factors are the principal mediators of cancer cells-stromal cell interaction , which is critical for invasion of cancer cells to the surrounding tissues and metastatic dissemination to distant organs. In this study, we studied VEGF-A, C expression in cultured human pancreatic cancer cell lines and whether the presence of VEGF-A, C in the cell lines is regulated by cytokines interleukin-lct (EL-1α), and interleukin-6 (IL-6). METHODS: We used Northern blot and Western blot methods to analyze expression of the gene and protein of VEGF-A, C in all 6 tested cell lines (ASPC-1, CAPAN-1, MIA-PaCa-2, PANC-1, COLO-357 and T3M4) respectively. To analyze what is the regulator for this VEGF-A, C expression in pancreatic cancer,we used the reverse transcription -polymerase chain reaction (RT-PCR) method to analyze VEGF-A, C expression in cultured human pancreatic cancer cell lines (CAPAN-1 and COLO-357) under the stimulation with IL-1α (10μg/L) or IL-6 (100 μg/L). RESULTS:Northern blot analysis revealed the presence of the 4.1-kb VEGF-A mRNA transcript and 2.4-kb VEGF-C mRNA transcript in all 6 tested cell lines. Immunoblotting with highly specific anti-VEGF-A, anti-VEGF-C antibody revealed the presence of a molecular weight of 43-kDa VEGF-A protein and 55-kDa VEGF-C protein in all the cell lines. RT-PCR analysis revealed the levels of the VEGF-A and VEGF-C gene were 1-2 fold and a 1-fold increase in the COLO-357 cell line by stimulation with IL-la, however, no effect was found in the CAPAN-1 cell line. The levels of the VEGF-A and VEGF-C gene were 2-5 fold and a 1-fold increase in the CAPAN-1 cell line by stimulation with IL-6, but, no effect was found in the COLO-357 cell line. CONCLUSION:These findings suggested that the expression of VEGF-A, C and their regulation by IL-1α, IL-6 in pancreatic cancer contributes to the lymphatic and distant metastasis and the disease progression. 展开更多
关键词 pancreatic cancer vascular endothelial growth factor VEGF-C CYTOKINE INTERLEUKIN-1Α INTERLEUKIN-6
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The Effect of Simvastatin on mRNA Expression of Transforming Growth Factor-β1,Bone Morphogenetic Protein-2 and Vascular Endothelial Growth Factor in Tooth Extraction Socket 被引量:10
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作者 Chang Liu Zhe Wu Hong-chen Sun 《International Journal of Oral Science》 SCIE CAS CSCD 2009年第2期90-98,共9页
Aim To determine the effect of local simvastatin application on the mRNA expression level of transforming growth factor-β1 (TGF-β1), bone morphogenetic protein-2 (BMP-2) and vascular endothelial growth factor (... Aim To determine the effect of local simvastatin application on the mRNA expression level of transforming growth factor-β1 (TGF-β1), bone morphogenetic protein-2 (BMP-2) and vascular endothelial growth factor (VEGF) in the tooth sockets of rat. Methodology Forty-eight male Wistar rats were randomly divided into experimental and control groups (n=24). Polylactic acid/polyglycolic acid copolymer carriers, with or without simvastatin, were implanted into extraction sockets of right mandibular incisors. The expression of TGF-β1, BMP-2 and VEGF mRNA was determined by in situ hybridization in the tooth extraction socket at five days, one week, two weeks and four weeks after implantation. Results The fusiform stroma cells in the tooth extraction socket began to express TGF-β1, BMP-2 and VEGF mRNA in both experimental and control groups from one week after tooth extraction until the end of experiment. The expression of TGF-131 and BMP-2 mRNA in the experimental group was significantly up-regulated after one, two and four weeks, and expression of VEGF mRNA was significantly increased after one and two weeks compared with that in the control group. Conclusion The findings indicate that local administration of simvastatin can influence alveolar bone remodeling by regulating the expression of a school of growth factors which are crucial to osteogenesis in the tooth extraction socket. 展开更多
关键词 bone morphogenetic protein-2 (BMP-2) in situ hybridization SIMVASTATIN tooth extraction socket transforming growth factor1 (TGF-β1 vascular endothelial growth factor (VEGF)
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ELEVATED SOLUBLE EPIDERMAL GROWTH FACTOR RECEPTOR LEVEL IN PITUITARY ADENOMA AND CARCINOMA 被引量:4
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作者 Yan-guoKong Zu-yuanRen Chang-baoSu Ren-zhiWang Wen-bingMa WeiLian 《Chinese Medical Sciences Journal》 CAS CSCD 2004年第3期199-202,共4页
To investigate effect of the soluble epidermal growth factor receptor (sEGFR/sErbB1) level in the periph-eral blood in development, invasiveness, apoplexy of each type of pituitary tumor. Methods The sEGFR level was d... To investigate effect of the soluble epidermal growth factor receptor (sEGFR/sErbB1) level in the periph-eral blood in development, invasiveness, apoplexy of each type of pituitary tumor. Methods The sEGFR level was determined in peripheral serum from 190 patients with pituitary diseases by enzyme linked immunosobent assay. The sEGFR levels were measured in 10 pituitary Rathke’s pouch, 18 pituitary hyperplasia, 161 pituitary adenomas including 30 microadenomas, 83 large adenomas, 48 giant adenomas, 1 pituitary carcinoma, and 28 hea-lthy controls. Results In the patients with pituitary hyperplasia, microadenoma, large adenoma, giant adenoma, and pituitary carci-noma, the sEGFR level was 188.92 ± 32.62, 209.83 ± 19.01, 333.20 ± 69.33, 405.85 ± 37.38, and 617.45 fmol/mL indepen-dently. They were all significantly higher than patients with pituitary Rathke’s pouch (156.78 ± 18.24 fmol/mL, P < 0.001) and healthy control group (159.11 ± 40.50 fmol/mL, P < 0.05). The sEGFR level in pituitary carcinoma was higher than pi-tuitary adenoma. In patients with pituitary adenoma, the sEGFR level was positive correlated to the size of pituitary adeno-mas (r = 0.998), the significant difference was observed for the sEGFR level in each group of the patients with pituitary adenomas (P < 0.001). Furthermore, in patients with pituitary ACTH-secreting microadenomas, the serum sEGFR levels in invasiveness (295.00 ± 77.80 fmol/mL) was higher than that in non-invasiveness (210.60 ± 16.4 fmol/mL, P < 0.05). In pati-ents with pituitary ACTH-secreting, PRL-secreting, GH-secreting, and non-functioning large adenomas, the serum sEGFR levels in invasiveness (407.86 ± 28.50, 399.25 ± 30.10, 386.00 ± 13.08, and 369.25 ± 36.70 fmol/mL) was higher than that in non-invasiveness (335.25 ± 63.49, 300.64 ± 47.57, 297.00 ± 61.93, and 269.30 ± 25.68 fmol/mL) respectively (P < 0.05). In patients with invasive pituitary PRL-secreting, GH-secreting, and non-functioning giant adenomas, the serum sEGFR levels not significantly different in between invasiveness (417.50 ± 35.94, 409.50 ± 69.14, and 417.50 ± 44.13 fmol/mL) and non-invasiveness (386.00 ± 49.64, 417.50 ± 44.03, and 409.51 ± 35.17 fmol/mL) (P > 0.05). In patients with pituitary large adeno-mas, the sEGFR levels in pituitary apoplexy (377.48 ± 39.18 fmol/mL) was higher than that in non-pituitary apoplexy (343.18 ± 68.17 fmol/mL, P > 0.05). Conclusions The increased level of peripheral serum sEGFR is concomitant with development, proliferous size of the adenomas in patients with pituitary adenomas. In addition, the elevated levels of serum sEGFR occur in pituitary apoplexy as clinical active tumors, and the non-invasive ACTH secreting adenomas. The sEGFR levels could be differen-tiated helpfully between pituitary adenomas and non-pituitary adenomas. These data suggest that serum sEGFR could be as a referable marker of the size and activation of proliferation in pituitary adenoma. 展开更多
关键词 pituitary adenoma pituitary carcinoma soluble epidermal growth factor receptor
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