急性白血病患者血清VEGF及VEGFR-2的临床研究

目的：探讨急性白血病（AL）患者血清中血管内皮生长因子（VEGF）及其受体2（VEGFR-2）的表达水平与临床的关系,以及血管新生在AL发病中的作用。方法：采用双抗体夹心ELISA法检测20例健康志愿者与39例AL初发患者未治时血清VEGF及VEGFR-2的含量,及25例获得完全缓解后的AL患者血清VEGF及VEGFR-2的水平;同时留取39例AL初发患者骨髓液涂片,进行瑞特染色后检测骨髓原始和幼稚细胞水平。结果：血清VEGF、VEGFR-2在AL初发组的含量明显高于正常对照组,尤其在未缓解组,P〈0.05;急性非淋巴细胞白血病（ANLL）和急性淋巴细胞白血病（ALL）之间血清VEGF、VEGFR2的水平差异无统计学意义（P〉0.05）;25例完全缓解的AL患者,其缓解前、后的血清VEGF、VEGFR2水平均高于正常对照组,差异有统计学意义（P〈0.05）,同时缓解后较缓解前血清VEGF、VEGFR2水平也明显下降（P〈0.05）;血清VEGF、VEGFR2的含量与患者骨髓中原始幼稚细胞水平有一定的相关性（均P〈0.05）。结论：提示AL患者有血管新生的存在,且血清VEGF及VEGFR-2水平与病情的特征以及预后的判断有一定的相关性。     

急性白血病骨髓中的血管生成的研究

目的 研究血管生成在急性白血病发病，预后中的作用。方法 应用免疫组化法检测30例初治急性白血病患者的骨髓活检组织治疗前后微血管密度（MVD）及血管内皮生长因子（VEGF）的变化。结果 初治急性白血病患者骨髓病理组织中的MVD和VEGF阳性率明显高于正常对照组；骨髓完全缓解后其MVD及VEGF阳性率明显下降，与正常对照组无显著性差异；治疗后未完全缓解组的MVD及VEGF阳性率较治疗前无显著性下降。结论 急性白血病骨髓中存在血管生成，可能与急性白血病的预后有关。     

急性白血病患者血清可溶性Fas和ICAM-1的检测及其与化疗相关性的探讨

目的检测急性白血病(AL)患者血清中可溶性Fas(sFas)和可溶性ICAM-1(sI-CAM-1)水平,探讨sFas与sICAM-1水平的改变与化疗的相关性。方法采用酶联免疫吸附实验检测58例急性白血病患者化疗前后血清sFas与sICAM-1的水平。结果化疗前AL患者血清sFas与sICAM-1水平均高于正常对照组;化疗后获得骨髓缓解的AL患者血清sFas与sICAM-1的水平显著低于化疗前,但未获缓解者血清sFas与sICAM-1的水平与化疗前无差异;不论是化疗前还是化疗后、获得缓解或未获得缓解的AL患者血清sFas水平与sICAM-1的水平呈正相关。结论AL患者血清sFas与sICAM-1水平升高是白血病细胞逃避机体免疫攻击的重要机制;其分泌水平的升高或降低与白血病细胞对化疗药物是敏感或耐受相关,也可能与化疗药物通过一种或多种机制作用于FasL/Fas或(和)ICAM-1/LFA-1信号途径相关。     

沙立度胺治疗急性白血病近期临床疗效观察

目的 探讨沙立度胺(反应停)在治疗急性白血病(AL)中的作用。方法 38例AL中,初治27例,随机分为常规化疗加反应停治疗(A)组和常规化疗(B)组。复治11例,列为C组,全部应用化疗加反应停。用Ⅷ因子相关抗原和CD34单抗免疫组化染色的方法,观察患者治疗前后骨髓微血管密度(MVD)。用ELISA的方法测定患者治疗前后血清血管内皮细胞生长因子(VEGF)的浓度。反应停起始剂量200mg/d,每1周增加50mg/d,直到400-500mg／d,应用4-6个月。结果 两组初治病例的完全缓解(CR)率和有效率：CR 部分缓解(PR)及达CR所需疗程数用或不用反应停均无差异,其CR率和有效率分别为57．1％和53．8％及78．6％和76．9％。复治组CR率27．3％,有效率54．5％。A、B两组CR患者随访6个月,A组复发率较低。患者MVD、VEGF治疗前与正常对照组相比差异非常显著(P＜0．001)。治疗前VEGF水平与疗效呈负相关。用反应停组无特殊的不良反应。结论 反应停治疗可维持AL患者的持续缓解状态,减少复发。在AL的治疗中加用反应停是合理的新的治疗策略。     

急性白血病患者血清血管内皮细胞生长因子测定及临床意义

目的探讨血管内皮细胞生长因子(VEGF)在急性白血病(AL)患者中的表达和临床意义.方法采用双抗体夹心ELISA法检测了41例AL初发患者(ANLL32例,其中是M14例、M24例、M38例、M44例、M512例和ALL9例)血清VEGF含量,并且检测了其中10例获得完全缓解后的AL患者血清VEGF水平;同时留取41例AL初发患者和10例获得完全缓解后AL患者骨髓涂片,进行瑞特染色后检测骨髓原始和幼稚细胞百分率.结果血清VEGF在ANLL和ALL中分别是(807.76±347.04)ng/L、(998.18±387.80)ng/L,均高于正常对照组(461.43±127.05)ng/L,均P＜0.01;ANLL和ALL之间血清VEGF水平差异无统计学意义(P＞0.05);10例完全缓解的AL患者,其血清VEGF含量为(495.28±102.79)ng/L明显低于初发时(1263.44±490.39)ng/L,P＜0.01;AL缓解组血清VEGF含量与其骨髓中原始幼稚白细胞百分率具有一定相关性,r=0.57,P＜0.01.结论血清VEGF在AL患者中明显升高,且血清VEGF水平与病情和预后密切相关.     

急性髓系白血病及骨髓增生异常综合征患者血管内皮生长因子表达的研究

目的了解血管内皮生长因子(VEGF)在急性髓系白血病(AML)和骨髓增生异常综合征(MDS)中血管新生的作用。方法用ELISA法检测20例AML及24例MDS患者骨髓单个核细胞培养上清VEGF的表达。结果AML患者骨髓细胞VEGF的水平(267.35～412.30ng/L)高于对照组(128.17ng/L),化疗后完全缓解组的VEGF水平明显下降(P<0.05)化疗后未缓解组的VEGF水平与治疗前比较无显著下降(P>0.05)。MDS高危型(RAEB或RAEBt)中VEGF水平与低危型(RA或RAS)及对照组相比均明显升高(P<0.05),其中RAEBt与AML患者相比差异无显著性(P>0.05)。结论AML及高危型MDS患者骨髓中存在血管新生,VEGF在AML及MDS发病中起着重要作用,VEGF的表达与MDS病程进展有关。     

急性白血病患者血管内皮生长因子及其受体表达的动态观察

目的探讨急性白血病(AL)患者治疗前后骨髓中血管内皮生长因子(VEGF)及其受体的表达差异以及这种表达与血管生成的相关性.方法应用EnVision免疫组织化学二步法,检测122例次成人AL患者骨髓中造血细胞VEGF及其两种特异性受体fms-样酪氨酸激酶受体(Flt-1)、激酶插入嵌合受体(KDR)蛋白的表达情况.结果化疗后获得完全缓解(CR)的患者,其VEGF、KDR蛋白的表达在治疗前为6.0(3.3～12.0)和5.3(3.3～8.0),获CR后为5.3(3.3～9.0)和2.0(1.0～4.0)差异有显著性(P<0.05;P<0.01),而在化疗后未获得CR患者中的表达差异无显著性.在缓解后复发患者中的表达又升高到初发时的水平.各组初发患者Flt-1的表达水平与对照组之间差异无显著性,但CR期Flt-1的表达水平在CR组为3.3(1.7～5.3),复发组为3.3(2.0～5.3)与初发及对照组差异有显著性(P<0.01).微血管数处于高水平组的VEGF及KDR表达显著高于微血管处于低水平组者(P<0.01).骨髓原始细胞与急性髓系白血病(AML)初发患者VEGF和KDR的表达之间成正相关(r=0.429,0.359;P=0.005,0.02);与急性淋巴细胞白血病(ALL)初发患者VEGF的表达之间成正相关(r=0.522,P=0.03).结论 VEGF及其两种特异性细胞受体Flt-1, KDR在造血细胞及血管内皮细胞中表达.提示VEGF可能是白血病细胞的一种自分泌因子,同时作为一种旁分泌因子调控患者骨髓中的血管新生反应.VEGF及其细胞受体KDR可能构成抗血管新生和抗白血病治疗的新靶点.     

VEGF在白血病患者血清中的表达及意义

采用ELISA法测定40例白血病患者治疗前后血管内皮生长因子(VEGF)的表达,并与对照组进行比较,同时检测骨髓幼稚细胞水平,分析VEGF与白血病类型、病情及预后的关系.结果 显示,白血病患者的血清VEGF水平明显高于正常对照组(P<0.05),血清VEGF水平与白血病病情正相关.认为检测血清中VEGF的表达对白血病的诊断、治疗和预后的判断有一定意义.     

多发性骨髓瘤患者骨髓微血管密度和血清β2-微球蛋白检测的临床意义

目的检测多发性骨髓瘤(MM)患者骨髓中血管新生的状态,探讨骨髓微血管密度(MVD)和β2-微球蛋白(β2-MG)与MM发展的关系。方法应用改良的塑料包埋骨髓活组织病理切片和免疫组织化学染色检测患者骨髓MVD;胶乳增强免疫透射比浊法测定MM患者血清β2-MG。结果初诊MM患者骨髓MVD明显高于正常对照组(P<0.01),与国际预后分期(ISS)及血清β2-MG相关(P<0.01),随临床分期的增加依次增高(P<0.01)。与治疗前相比,MM治疗有效组骨髓MVD水平明显下降(P<0.01),治疗无效组差异无统计学意义(P>0.05)。结论骨髓MVD及血清β2-MG检测可作为MM患者体内瘤负荷、预后及疗效判断的指标,骨髓血管新生在MM发生、发展过程中发挥重要作用,抗血管新生治疗可能成为治疗MM的新策略。     

急性白血病抗血管新生治疗中的护理

为探讨抑制血管新生在治疗急性白血病 (AL)中的护理方法 ,将 2 7例初治患者随机分为常规化疗组(B组 )及联用反应停组 (A组 )两组。 11例复治患者 (C组 )均联用化疗药物及反应停。用 因子相关抗原和 CD3 4单抗免疫组化染色的方法 ,观察患者治疗前后骨髓微血管密度 (MVD)。用 EL ISA的方法测定患者治疗前后血清血管内皮细胞生长因子 (VEGF)的浓度。反应停剂量 2 0 0～ 5 0 0 mg/ d,连用 4～ 6个月。结果两组初治病例的疗效无差异 ,复治组 CR率 2 7.2 7% ,A、B两组 CR患者随访 6个月 ,A组复发率较低。患者 MVD、VEGF治疗前与对照组 (15例健康体检正常者 )相比 ,差异非常显著 (P<0 .0 0 1)     

Role of the microenvironment in promoting angiogenesis in acute myeloid leukemia

Angiogenesis is a crucial event in the survival and progression of solid tumors. To determine whether angiogenesis in acute myeloid leukemia (AML) is an intrinsic property of leukemic cells, the vascularity of bone marrow biopsies was determined. Bone marrow vascularity in newly diagnosed or post-chemotherapy AML patients was increased 4-fold (P < 0.01) and 8.7-fold (P < 0.01), respectively, relative to controls. Vascular endothelial growth factor (VEGF) expression by AML blast cells was assessed by immunohistochemistry, and bone marrow cell supernatants were assayed for secretion of VEGF, fibroblast growth factor-2 (FGF-2), and endostatin by enzyme-linked immunosorbent assay. Diffuse cytoplasmic and strong extracellular VEGF immunoreactivity was seen in bone marrow aspirates from AML patients, but not controls. In contrast, there was no difference in the levels of VEGF, FGF-2, and endostatin secreted by mononuclear cells cultured from bone marrows of AML patients compared to normal controls following two days of culture in vitro. Total angiogenic potential of bone marrow cell supernatants was assessed by endothelial sprouting in vitro and by a chick chorioallantoic membrane assay. No differences were found between 2-day conditioned medium from normal and AML bone marrow mononuclear cells in either assay. Our data show a discrepancy between bone marrow vascularity and VEGF expression in vivo and VEGF expression and angiogenesis from 2-day conditioned medium ex vivo. This suggests that angiogenesis in AML likely represents a response to microenvironmental factors in vivo, rather than being an intrinsic property of leukemic cells.     

Increased angiogenesis in the bone marrow of patients with acute myeloid leukemia

The importance of angiogenesis for the progressive growth and viability of solid tumors is well established. In contrast, only few data are available for hematologic neoplasms. To investigate the role of angiogenesis in acute myeloid leukemia (AML), bone marrow biopsies from 62 adults with newly diagnosed, untreated AML (day 0) were evaluated. Further studies were done after the completion of remission induction chemotherapy (day 16 of induction chemotherapy, n = 21; complete remission, n = 20). Microvessels were scored in at least 3 areas (x500 field, 0.126 mm(2)) of the highest microvessel density in representative sections of each bone marrow specimen using immunohistochemistry for von Willebrand factor and thrombomodulin. Microvessel counts were significantly higher in patients with AML (n = 62) compared with control patients (n = 22): median (interquartile range) 24.0 (21.0-27.8)/x500 field vs 11.2 (10. 0-12.0)/x500 field, respectively (P <.001). On day 16 of induction chemotherapy, microvessel density was reduced by 60% (44-66) (P <. 001) in hypoplastic marrows without residual blasts, in contrast to only 17% (0-37) reduction in hypoplastic marrows with >/= 5% residual blasts (P <.001 for the difference between both groups). Bone marrow biopsies taken at the time of complete remission displayed a microvessel density in the same range as the controls. In conclusion, there is evidence of increased microvessel density in the bone marrow of patients with AML, which supports the hypothesis of an important role of angiogenesis in AML. Furthermore, these findings suggest that antiangiogenic therapy might constitute a novel strategy for the treatment of AML. (Blood. 2000;95:2637-2644)     

血管内皮生长因子、环氧化酶-2在急性白血病中的表达及其与血管新生的关系

目的探讨血管内皮生长因子（VEGF）、环氧化酶-2（COX-2）在急性白血病（AL）的表达及与血管新生的关系。方法应用酶联免疫吸附试验（EHSA）测定23例AL初发未治,21例完全缓解（CR）,18例复发患者血清中VEGF、COX-2的含量,并与正常对照组比较。结果AL初发未治组、复发组患者血清VEGF、COX-2的含量明显高于正常对照组,差异有统计学意义（P〈0．01）;CR组患者血清VEGF、COX-2的含量较初发未治组明显下降,与正常对照组比较,差异无统计学意义（P〉0．05）;复发组血清VEGF、COX-2的含量明显高于CR组,差异有统计学意义（P〈0．01）。结论VEGF、COX-2与AL的发生、发展密切相关,COX-2可能通过上调VEGF促进AL的血管新生及发生、发展,抗VEGF和COX-2有望成为白血病治疗新的靶点。     

Bone marrow angiogenesis in aplastic anemia – a study of CD 34 and VEGF expression in bone marrow biopsies

Abstract

Introduction: Bone marrow function and the growth of hemopoietic cells depends on an intact microvasculature. A pivotal regulator of angiogenesis is vascular endothelial growth factor (VEGF). Our study assesses VEGF expression and microvessel density (MVD) in the bone marrow of patients with aplastic anemia (AA).

Materials and method: Bone marrow specimens from 25 patients with AA and 15 controls were studied. MVD was calculated on sections stained immunohistochemically for CD34. Subsequently, all the cases were studied for VEGF expression.

Results: Bone marrow MVD in patients with AA was significantly lower than that in controls (p<0·01). There was a significant MVD difference between severe AA and moderate AA (p<0·05). VEGF expression was also significantly lower in AA cases compared to controls (p<0·05).

Conclusion: Our data show that AA is associated with reduced angiogenesis and reduced VEGF expression. Defective angiogenesis may result in or aggravate bone marrow aplasia in AA patients. There are limited studies on this aspect. More studies to confirm the present hypothesis might pave the way for new treatment options in AA.     

Study of prognostic significance of marrow angiogenesis assessment in patients with de novo acute leukemia

Abstract

Background

Angiogenesis is the highly ordered formation of new blood vessels from pre-existing vessels. It is seen throughout growth, in wound healing, menses, and is important in cancer, where pro- and antiangiogenic signals can be released by cancer cells, endothelial cells, stromal cells, blood, and the extracellular matrix.

Aim of the study is to use standardized method for counting blood vessels to verify the significance and prognostic value of assessing marrow angiogenesis at diagnosis of de novo acute leukemia.

Subjects and methods

The study included 70 newly diagnosed acute leukemia cases and a control group composed of 35 bone marrow biopsy sections obtained from breast cancer patients. Examination of CD34 immunohistochemically stained sections for the assessment of marrow angiogenesis by quantification of its microvessel density (MVD).

Results

MVD was significantly increased in acute leukemia patients in comparison to control group (P-value <0.001). Increased MVD was associated with unfavorable outcome.

Conclusion

The study demonstrated an evidence of increased angiogenesis in acute leukemia detected by high bone marrow MVD which may play a significant role in leukemic process. Understanding its role may help in designing new therapeutic strategies for acute leukemia.     

Endostatin serum level in acute myeloid leukemia

Increased levels of tumor angiogenesis have been demonstrated in variety of solid tumors and hematological malignancies including acute myeloid leukemia (AML). The aim of the study was to evaluate serum level of endostatin in newly diagnosed patients with AML before chemotherapy and after achieving complete remission (CR). Serum samples from 68 adult patients (28 females and 40 males, median age 42 years, range 21-83 years) with AML had been taken before chemotherapy was administered. In addition 21 out of 68 patient were analyzed again after achieving CR. Endostatin levels were measured using ChemiKine sandwich ELISA kit (Chemicon International). Twelve samples from healthy volunteers (5 females and 7 males, median age 40 years; range 35-65 years) were evaluated as the control. Endostatin serum levels were significantly higher in untreated AML patients than in the normal controls. In AML patients baseline endostatin levels were significantly lower than in CR. We did not found any correlation between white cell count or percentage of blasts in the bone marrow and endostatin level. Moreover endostatin levels did not differ statistically among AML FAB subgroups. Increased endostatin plasma levels may reflect intensity of inhibition of angiogenesis and may by useful in prognosis of CR in AML. Chemotherapy can modulate the regulation of angiogenesis in AML patients.     

Increased expression of vascular endothelial growth factor in bone marrow of multiple myeloma patients

Background: Angiogenesis (neovascularization) is a multistep process in which new blood vessels grow from existing vessels. Angiogenesis is associated with the growth, dissemination, and metastasis of solid tumors. There is increasing evidence that neovascularization may be important in hematological malignancies. Several studies suggest that vascular endothelial growth factor (VEGF) is one of the most important cytokines responsible for the development, maintenance, and progression of multiple myeloma (MM) by promoting bone marrow angiogenesis. A high serum concentration of VEGF has been reported in MM patients. The aim of this study was to evaluate the expression of VEGF in the bone marrow of MM patients. Methods: Eighteen paraffin-embedded bone marrow core biopsy specimens from newly diagnosed patients with MM were evaluated. In addition, 10 bone marrow core biopsy specimens from adult patients without evidence of malignancy were used as controls. Bone marrow sections were stained immunohistochemically for VEGF. Results: Our data show that multiple myeloma is associated with an increased expression of VEGF in the bone marrow. Conclusions: Our observation supports previous studies suggesting that angiogenesis may play a role in the pathophysiology of hematopoietic malignancies. The clinical significance of this phenomenon needs further investigation. However, this study provides rationale for the use of angiogenesis inhibitors in MM therapy.