PD-ECGF、HGF在胶质瘤中的表达及与肿瘤血管生成的关系

The expression of PD-ECGF and HGF in glioma and their relationships with tumor angiogenesis

目的探讨胶质瘤组织中血小板源性内皮细胞生长因子(PD-ECGF)、肝细胞生长因子(HGF)的表达及与肿瘤血管形成的关系。方法用逆转录聚合酶链反应(RT-PCR)测定了30例胶质瘤和6例正常脑组织的PD-ECGF mRNA水平,用NIH Image软件量化分析目标PCR条带的面积与吸光度;采用原位杂交法检测HGF mRNA的表达;用免疫组化法检测CD34的表达,计算徽血管密度(MVD),并结合临床和病理资料进行分析。结果胶质瘤组织中PD-ECGF基因呈过度表达,高级别(Ⅲ～Ⅳ级)胶质瘤组织中PD-ECGF mRNA的平均表达水平(0.73±0.18)显著高于低级别(Ⅰ～Ⅱ级)胶质瘤(0.47±0.33)及正常脑组织(0.11±0.17),三组比较差异有显著性(P=0.000);生存时间≥2年组中PD-ECGF mRNA的表达水平(0.47±0.29)低于生存时间<2年组(0.81±0.11),差异有显著性(P=0.001)。HGF mRNA在正常脑组织均未见表达,在低级别和高级别胶质瘤组织中阳性率分别为35.7%和75.0%,差异有显著性(P=0.0301;生存时间≥2年组中HGF mRNA的阳性表达率(27.8%)低于生存时间<2年组(83.3%),差异有显著性(P=0.003)。MVD在正常脑组织、低级别和高级别胶质瘤组织中分别为(8±4)个、(20±7)个和(29±6)个,差异有显著性(P=0.000);MVD和PD-ECGF mRNA、HGF mRNA之间存在显著正相关(r_1=0.390.P_1=0.033;r_2=0.514,P_2=0.004),PD-ECGF mRNA和HGF mRNA之间存在显著正相关(r=0.370,P=0.044)。结论胶质瘤中MVD比正常脑组织显著增高,显示了胶质瘤丰富血供的肿瘤血管生成特征。PD-ECGF、HGF在胶质瘤中的表达显著增强,在肿瘤血管生成中起着重要作用,能共同调节胶质瘤的血管形成,可用于判断胶质瘤的生物学行为,并对判断预后有指导意义。

Objective To investigate the expression ofplatelet-derived endothelial cell growth factor （PD-ECGF） and hepatocyte growth factor （HGF） in glioma, their relationships with tumor angiogenesis, and the significance of tumor angiogenesis in glioma. Methods Reverse transcription-polymerase chain reaction （RT-PCR） was applied to determine mRNA expressions of PD-ECGF in 30 patients with glioma and 6 normal brain tissues, and a computer software NLH Image was applied to quantitatively analyze the area and absorbance of the target PCR bands; in situ hybridization （ISH） was applied to localize the expression of HGF mRNA; immunohistochemistry was applied to detect the CD34 expression and determine microvessel density （MVD）, and analyses were made based on the combination of clinical and pathological data. Results The PD-ECGF gene was overexpressed in glioma tissues, the average expression （0.73±0.18） of PD-ECGF mRNA in high-grade glioma tissues （Grade Ⅲ- Ⅳ ） was evidently higher than that （0.47±0.33） in low-grade （Grade Ⅰ - Ⅱ ） and that （0.11 ± 0.17） in normal brain tissues, and comparisons between the three groups showed significant differences statistically （P=-0.000）; the expression （0.47±0.29） of PD-ECGF mRNA in the group with the survival time 〉1 2 years was lower than that （0.81±0.11） in the group with the survival time 〈 2 years, and differences between the two groups were significant statistically （P=0.001）. There was no expression of HGF mRNA in normal brain tissues, the positive rates of HGF mRNA in low-grade and high-grade glioma tissues were respectively 35.7% and 75.0% （P=0.030）, and the positive expression rate （27.8%） of HGF mRNA in the group with the survival time ≥ 2 years was lower than that （83.3%） in the group with the survival time 〈 2 years, differences between the two groups significant statistically （P=-0.003）. Expressions of MVD were （8±4）, （20±7） and （29±6） respectively in normal brain tissues, low-grade and high grade glioma tissues （P=-0.000）; MVD and PD-ECGF mRNA, MVD and HGF mRNA were evidently positively correlated with each other （r1=0.390, P1=0.033; r2=0.514, P2=0.004）; PD-ECGF mRNA and HGF mRNA were evidently positively correlated with each other （r=0.370, P=0.044）. Conclusion MVD in glioma is obviously higher than that in the normal brain tissue, showing the affluent blood supply feature of glioma during tumor angiogenesis. The expressions of PD-ECGF and HGF is obviously higher than that in the normal brain tissue an play an important role in tumor angiogenesis. They may regulate the microvessel formation in glioma simultaneously and can be used to determine the biologic behaviors and prognosis of glioma.