Avastin联合环磷酰胺治疗神经母细胞瘤裸鼠移植瘤的研究

目的 探讨Avastin抗神经母细胞瘤(NB)裸鼠移植瘤生长的作用,以及对血清血管内皮生长因子(VEGF)水平的影响.方法 培养NB细胞并建立NB裸鼠移植瘤.用Avastin单药或与环磷酰胺(CPM)联合治疗NB裸鼠移植瘤.Avastin剂量为5 rag/kg,由尾静脉注入,每周1次;CPM75 mg/kg,仅1次.于第22天处死裸鼠,计算肿瘤体积及抑瘤率.应用抗CD34免疫组化法检测肿瘤微血管密度,ELISA法测定各组治疗结束后血清VEGF(sVEGF)水平.结果 Avastin单药治疗、CPM单药化疗、Avastin联合CPM治疗NB裸鼠移植瘤的抑瘤率分别是44.0%、38.1%、62.8%.Avastin联合CPM化疗与Avastin单药治疗和CPM单药化疗比较,差异均有统计学意义(P＜0.05).Avastin对NB血管生成的抑制率为64%.Avastin治疗后尽管裸鼠肿瘤已明显缩小,但sVEGF升高至对照组的1.9～2.4倍.结论 Avastin能抑制NB裸鼠移植瘤的生长,而且与CPM有协同抗NB作用.sVEGF不能用于监测Avastin抗瘤效果.     

Prognostic and biological role of neurotrophin-receptor TrkA and TrkB in neuroblastoma

Expression of different neurotrophin receptors of the tyrosine kinase (Trk) family plays an important role in the biology and clinical behavior of neuroblastomas (NB). Observations from several independent studies suggest that high expression of TrkA is present in NB with favorable biological features and highly correlated with patient survival, whereas TrkB is mainly expressed on unfavorable, aggressive NB with MYCN-amplification. To determine expression of Trk receptors and ligands in primary NB, we developed a reliable semiquantitative duplex RT-PCR protocol, that requires only 1 microgram RNA per tumor sample. Activation of TrkA by its ligand nerve growth factor (NGF) initiates a cascade of signaling events and promotes neuronal differentiation in vitro. Activation of TrkB by its ligand brain derived neurotrophic factor (BDNF) has been associated with proliferation and survival of NB cells. To study Trk signal transduction pathways and their biological effects in NB, we stably expressed TrkA and TrkB cDNA in the human NB cell line SH-SY5Y. Introduction of TrkA and TrkB restored responsiveness of SH-SY5Y cells to the ligands NGF and BDNF, respectively, and resulted in morphological differentiation. Expression of TrkA resulted in growth inhibition of the transfectants compared to parental cells, whereas TrkB transfectants demonstrated an increased proliferation rate. Further insight into the differences of TrkA and TrkB signaling may suggest new options for the treatment of NB. As expression of TrkA is a strong prognostic factor especially in MYCN non-amplified NB, a prospective study of Trk receptor expression using RT-PCR should be performed for German neuroblastoma patients.     

Biological stability of RNA isolated from RNAlater-treated brain tumor and neuroblastoma xenografts

BACKGROUND: Advances in molecular biological research have led to identification of prognostic factors such as Trk mRNA expression in primitive neuroectodermal tumors of the CNS and neuroblastoma. To study prospectively the importance of these prognostic factors in large groups of homogeneously treated patients, tumor specimens of good quality must be acquired, preserved, and stored at multiple institutions. Immediate freezing of tumor biopsy samples in liquid nitrogen and storage at -70 degrees C are the most commonly used method of tissue preservation for future RNA analysis. PROCEDURE: To evaluate alternative methods of preserving tissue samples for subsequent RNA analysis, we tested a new RNA stabilization solution. Using tumor tissue of two CNS tumor and one neuroblastoma human xenografts, we compared total RNA isolated from tumor tissue stored for 7 days at room temperature in stabilization solution to that of snap-frozen tissue. The quality of the RNA was studied by spectrophotometry, gel electrophoresis, RT-PCR, and gene expression profiling. RESULTS: No major differences were observed in the quality of RNA isolated from tumor samples stored at room temperature in the RNA stabilization solution compared to snap-frozen tumor samples stored at -70 degrees C. CONCLUSIONS: High-quality RNA can be prepared from tumor tissue stored at room temperature. Whenever snap freezing is not feasible, pieces of tumor tissue can be treated with RNAlater for subsequent RNA analysis. Short-term storage and shipment of well-preserved tumor tissue are clearly feasible for all institutions, thereby facilitating large multiinstitutional studies of biological prognostic factors.     

The anti-VEGF antibody bevacizumab potently reduces the growth rate of high-risk neuroblastoma xenografts

Neuroblastoma (NB) is a rapidly growing, well-vascularized childhood cancer that often presents with metastases. The overall five-year survival in NB is approximately 45% despite multimodality treatment, and therefore there is a clinical need for new therapeutic strategies. NB frequently overexpresses the angiogenic factor VEGF (vascular endothelial growth factor). The aim of this study was to investigate the effect of bevacizumab (Avastin, Genentech/Roche), a humanized anti-VEGF-A antibody, on NB growth in three different xenograft models, chosen to resemble high-risk NB. The human NB cell lines SK-N-AS, IMR-32 and SH-SY5Y, which are poorly differentiated and overexpress VEGF-A, were injected s.c. in immunodeficient mice. Bevacizumab was given intraperitoneally twice weekly at 5 mg/kg body weight, starting at a tumor volume of 0.3 mL. Bevacizumab significantly (p < 0.01-0.05) reduced NB growth in vivo without toxicity by causing a 30-63% reduction of angiogenesis, but had no effect on NB cell survival in vitro. Serum concentrations of VEGF-A increased two- to six-fold during bevacizumab therapy which did not result in faster tumor growth compared with control animals. Based on our experimental data we suggest consideration of bevacizumab in treatment of high-risk NB that does not respond to conventional therapy and that overexpresses VEGF.     

Grading procedures for neuroblastoma (author's transl)

Various procedures of practical significance for grading neuroblastoma are described. The comparability of the grading procedures was studied on the basis of a series of 75 cases of neuroblastoma. When the grading procedure of Hughes et al. was applied to the material collected at the Childhood Tumor Registry in Kiel, the proportions of the various grades of malignancy agreed with the data on the collection in Manchester. More than 50% of the cases of neuroblastoma were undifferentiated, corresponding to grade III. An anaplastic type of neuroblastoma is also described. When applying grading procedures, one has to take the possible variations in the histologic picture of neuroblastoma into consideration.     

Avastin对神经母细胞瘤株SK-N-SH增殖影响的体外研究

目的 以人神经母细胞瘤SK-N-SH细胞株为研究对象探讨Avastin对其增殖的影响及可能机制.方法测定不同 Avastin浓度对SK-N-SH细胞上清液VEGF水平的影响,对该株细胞的细胞毒作用及对其细胞周期及凋亡的影响.结果 随着Avastin浓度升高,细胞上清液中游离VEGF水平逐渐下降;在一定剂量范围内,Avastin对该株细胞无明显细胞毒性作用;不同浓度Avastin作用于该株细胞,呈时间依赖性,影响细胞周期分布.结论 Avastin可中和SK-N-SH细胞分泌的VEGF,无明显细胞毒性作用,但可影响细胞周期分布,提示Avastin与化疗药物联合应用可能有协同作用.     

三氧化二砷对人神经母细胞瘤细胞凋亡作用的影响

目的：三氧化二砷(As2O3 )通过诱导细胞凋亡和诱导细胞分化效应治疗急性早幼粒细胞白血病(APL)患者已取得很好疗效。与APL细胞相似,神经母细胞瘤(NB)细胞也是分化成熟受阻,该文对As2O3 在体外对人神经母细胞瘤细胞凋亡作用的影响及可能的机制进行探讨。方法：比色法观察As2O3 对神经母细胞瘤SK N SH细胞增殖的影响;Giemsa染色观察细胞形态学改变;Annexinⅴ/PI双染色流式细胞术检测细胞凋亡;免疫细胞化学染色方法检测bcl 2蛋白表达变化。结果：As2O3 明显抑制SK N SH细胞增殖,抑制作用呈剂量时间依赖效应,并出现细胞凋亡的形态学改变;流式细胞仪检测4. 0μmol/LAs2O3 作用SK N SH细胞72h后,早期凋亡细胞比例( 9. 9±0. 8 )%,与对照组( 3. 7±0. 2 )%相比明显增多,差异有显著性(P< 0. 05 );分别以1. 0, 2. 0,4. 0μmol/L的As2O3 处理SK N SH细胞72h后,bcl 2表达随As2O3 浓度增加呈降低趋势,bcl 2表达阳性率分别为(26. 3±8. 0)%, (15. 0±4. 5)%和(4. 8±3. 2)%,与对照组(73. 6±6. 1)%相比,差异有显著性(P<0. 01)。结论：As2O3 可在体外抑制神经母细胞瘤细胞增殖,诱导凋亡,bcl 2参与了其调节作用。     

Results of neuroblastoma treatment in Austria (1979-1984)

During the period from 1979 until 1984 55 children were registered: 4 in Evan-stage I, 13 in stage II, 16 in stage III, 18 in stage IV and 4 in stage IV-S. 39 of these 55 patients have been followed for a minimum of two years. The current two year survival rate is 10/10 in stages I and II, 6/13 in stage III, 3/14 in stage IV and 2/2 in stage IV-S. These results demonstrate but a slight improvement in patients with stage II since the last Austrian statistic 1974. Despite modern chemotherapy the chance for survival of children with stage III or IV neuroblastoma is poor and better treatment modalities should be searched for.     

131(I)-meta-iodobenzylguanidine treatment of 32 children with therapy-refractory neuroblastoma

The selective uptake and accumulation of 131J-Metaiodobenzylguanidine in neuroblastoma cells in vivo may be utilized for targeted irradiation. The experience with 32 neuroblastoma patients refractory to conventional high dose chemotherapy is reported. At diagnosis 8 patients had Evans stage III and 22 stage IV. 11/32 experienced recurrences after complete tumor disappearance and before mIBG treatment, 16/32 progressed from residual or nonresponding tumor and in 3/32 insufficient tumor regression by chemotherapy was observed. 2 children received one mIBG course each with no evidence of disease. Mean applied activity was 128 mCi per course (35-300 mCi), 360 mCi per patient (80-1033 mCi) and 19.2 mCi/kg per patient (3.2-37.9 mCi/kg), respectively. A total of 84 courses was given (mean 2.6 per patient). Pain relief was noticed in 14/14 patients with bone pain. Complete or very good partial remission was achieved in 5/32, partial remission in 11/32 and stable disease in 6/32 patients. In 8 children progression occurred and 2 patients were not evoluable. 20 children died, 12 are still alive (6 patients with initial stage IV, 6 with stage III disease). Main side effect was transient thrombocytopenia, which became more severe with increasing number of courses. We conclude that mIBG treatment is effective in some patients with refractory neuroblastoma and may be utilized in the future as front line therapy for patients achieving only incomplete regressions after high dose chemotherapy.     

Effect of combined cyclooxygenase-2 and matrix metalloproteinase inhibition on human sarcoma xenografts

PURPOSE: Sarcomas express cyclooxygenase (COX)-2, an inducible enzyme with known tumor-promoting activity. COX-2 inhibition is efficacious against many cancer types but has not been tested for human sarcomas. Matrix metalloproteinase (MMP) inhibitors also possess antiproliferative activity. Because MMP inhibitor therapy induces COX-2 expression, the authors hypothesized that the combination of COX-2 and MMP inhibitors results in a synergistic antitumor effect. METHODS: Human osteosarcoma or rhabdomyosarcoma cells were injected into athymic mice. Tumor development and growth were measured following treatment with a COX-2 inhibitor (celecoxib), an MMP inhibitor (doxycycline), or both. The tumors were analyzed for necrosis, apoptosis, cyclooxygenase activity (PGE2 production), and MMP-2 levels. RESULTS: When treatment was started prior to tumor cell implantation, doxycycline inhibited osteosarcoma tumor growth alone and in combination with celecoxib (30% and 33% reduction, respectively). An effect on osteosarcoma tumor implantation rates was noted in mice receiving doxycycline alone and in combination with celecoxib (12.5% and 6.25% reduction, respectively). Established osteosarcoma and rhabdomyosarcoma tumors were inhibited only by combination therapy (36% and 55%, respectively). A higher proportion of osteosarcoma tumors in the combination therapy group had more than 50% necrosis (3/7) when compared with control tumors (0/8). Antitumor effects did not correlate with PGE2 levels, suggesting the observed interaction with doxycycline was due to previously described non-enzymatic effects of celecoxib. CONCLUSIONS: The authors' preclinical data suggest that the combination of inexpensive, nontoxic, oral COX-2 and MMP inhibitors may be useful for the treatment of some types of solid tumors.     

E-钙黏蛋白在神经母细胞瘤上皮-间质转化中的作用

目的:研究神经母细胞瘤中E-钙黏蛋白(E-cadherin)的表达在肿瘤转化生长因子-β1(TGF-β1)诱导的上皮-间质转化(EMT)中的作用。方法:体外采用TGF-β1(1 μg/L、5 μg/L、10 μg/L)处理人神经母细胞瘤SK-N-SH细胞株,与空白对照组比较,采用荧光定量PCR及Western blot...     

Combined (111)In-pentetreotide scintigraphy and (123)I-mIBG scintigraphy in neuroblastoma provides prognostic information

BACKGROUND: High-affinity somatostatin receptors (SRs) have been characterized in neuroblastomas and may be used as target structures for in vivo detection of SR. PROCEDURE: Eighty-eight children with histologically proven neuroblastoma were investigated at diagnosis or relapse by (123)I-mIBG and (111)In-pentetreotide scintigraphy. All tumors were investigated for MYCN copy number, chromosome 1p36 status, and 68/88 also for DNA content, followed for a median follow-up of 35 months (range 1-88 months). RESULTS: SR expression was detected in 56/88 tumors and (123)I-mIBG showed positivity in 83/88. (111)In-pentetreotide was less sensitive in detecting tumor tissue than was (123)I-mIBG (64% vs. 94%, P = 0.005). Survival (SUR) and event-free survival probability (EFS) according to Kaplan-Meier was significantly better for children with positive SR scintigraphy than for the children with a negative SR scan (SUR: 90% vs. 48% at 4 years log rank P < 0.003, EFS: 83% vs. 39% at 4 years, log rank P < 0.0002). CONCLUSIONS: (123)I-mIBG scintigraphy remains the best scintigraphic method for detecting neuroblastoma tumor tissue, whereas additional SR scintigraphy is able to provide significant prognostic information with a minimum of invasiveness.     

双酚A对人神经母细胞瘤SK-N-SH细胞增殖的影响

目的探讨双酚A（BPA）对人神经母细胞瘤SK—N—SH细胞增殖的影响及其可能机制。方法SK—N—SH细胞经培养扩增后分为5组：组1，无干预（对照组）；组2，加17p雌二醇（E2）；组3，加BPA；组4，同时加E2和ICI 182，780；组5，同时加BPA和ICI182，780。分别在0h、24h、48h和72h进行光吸收度值（AV）检测，在72h进行流式细胞仪DNA增殖指数（PI）检测。结果组3的AV在24h、48h、72h均明显增加，分别是组1的1．53、1．25、1．20倍，72h时的PI是组1的1．42倍。组2的结果与组3相似。组4、5中细胞增殖受到ICI182，780的明显抑制。结论BPA能促进人神经母细胞瘤SK—N-SH细胞的体外增殖，该促增殖作用可能是通过雌激素受体依赖途径实现的。