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11.
Manoussos M. Konstadoulakis MD Michael Vezeridis MD Emi Hatziyianni MD Constantine P. Karakousis MD PhD Bernard Cole PhD Kirby I. Bland MD Harold J. Wanebo MD 《Annals of surgical oncology》1998,5(3):253-260
Background: Oncogenes and other molecular tumor markers that predict tumor aggressiveness may allow individualization and optimization of surgical therapy of intermediate-thickness malignant melanoma. We examined the expression of selected markers, including the HLA-DR antigen, the heat shock protein-70 (HSP-70), and the c-myc oncogene in primary melanoma and regional nodes and related these findings to metastatic potential and survival.
Methods: Forty patients with primary melanoma (1.5–4.0 mm) were studied, all of whom had prophylactic lymph node dissection and were followed for 18 months to 7 years. The primary tissue and nodes were examined using immunohistochemical techniques for the presence of HLA-DR antigen and HSP-70 protein and the expression of the c-myc oncogene.
Results: Of 40 patients, there were 23 with lesions 1 to 2.9 mm thick and 17 with lesions 3 to 4 mm thick. Nodal metastases were present in 25 of the 40 patients who had elective node dissection. HLA-DR antibody stained the primary tumor in 10 patients (25%), but there was no correlation with survival in this group. HLA-DR antibody stained the stroma and cellular infiltrates surrounding the primary tumor in 28 of 40 patients; in this group there was a correlation of HLA-DR staining of the peritumoral stroma with improved survival overall. HLA-DR staining of the peritumoral stroma also influenced survival when patients were stratified by tumor thickness groups 1 to 2.9 mm and 3 to 4 mm and presence of nodal metastases. HSP-70 was demonstrated in the primary tumor in 25% of patients, who were also shown to have significantly improved survival when compared with those whose primary tumor did not stain with HSP-70. C-myc was expressed in the primary tumor in 25%, but showed no correlation with survival. None of these proteins correlated with or predicted the presence of nodal metastases.
Conclusion: We conclude that the use of specific molecular-oncogene markers in intermediate-thickness primary melanoma may identify patients at high risk for conventional treatment failure and reduced survival who may profit from more aggressive surgery, adjuvant therapy, or both.Presented at the 48th Annual Cancer Symposium of The Society of Surgical Oncology, Boston, Massachusetts, March 23–26, 1995. 相似文献
12.
膜表达热休克蛋白70真核表达载体的构建及其对肿瘤细胞的转染 总被引:2,自引:0,他引:2
目的构建普遍适合性的膜表达热休克蛋白70(HSP70)的真核表达载体,修饰并建立HSP 70表达并结合在细胞膜表面的肿瘤细胞.方法RT-PCR法从人胚肾中获取HSP 70的cDNA,扩增成带酶切位点的目的基因.选择载体pDisplay,将目的基因插入载体多克隆酶位点中.DNA测序证实后,以脂质体转染的方法,将载体转染到黑色素瘤细胞.用G418抗性筛选获得阳性克隆.结果酶切电泳和DNA测序证实载体构建正确;目的基因的上游带信号肽序列,下游带跨膜序列.RT-PCR产物电泳、Westem Blotting、激光共聚焦显微镜和流式细胞术证实大量HSP 70表达并结合在转染的黑色素瘤细胞膜表面.结论成功地构建了膜表达HSP 70的真核表达载体;转染到黑色素瘤细胞后,细胞膜表面表达丰富的HSP70.转染细胞可以进一步制备新型瘤苗. 相似文献
13.
Inhibitory Effect of Angiogenesis Inhibitor TNP—470 on Human ACHN Renal Cell Carcinoma 总被引:2,自引:0,他引:2
Angiogenesis,the formation of new bloodvessels,is necessary for the growth of tumors andtheir metastasis.TNP- 470 is a synthetic analogueof fumagillin and has stronger antiangiogenic ac-tivity and less side- effects than fumagillin.Thiscompound has been reported to suppress the prolif-eration and metastasis of various kinds of tu-mors[1] . Using nude mice xenografts of ACHN hu-man renal cell carcinoma ( RCC) ,the presentstudyattempted to examine the action of TNP- 470 ongrowth,metastasi… 相似文献
14.
目的定量研究汉滩病毒(HTNV)体外诱导细胞热休克蛋白70(HSP70)及HSP70 mRNA的表达规律。方法以HTNV敏感细胞株Vero-E6为对象,体外实验性感染Hantaan 76—118。采用原位杂交、免疫细胞化学染色法及逆转录聚合酶链反应(RT-PCR)观察感染后72h内HSP70的表达并加以定量分析。结果与模拟感染组相比,Hantaan 76—118感染Vero-E6细胞后0.5h,HSP70 mRNA开始升高,于感染后12h达高峰,并持续高表达至72h(P<0.05)。Hantaan 76—118感染后2h可检测到HSP70蛋白表达增加,于感染后12h达高峰,并持续高表达至72h(P<0.05)。结论体外感染HTNV可诱导Vero-E6细胞产生热休克反应并表达HSP70,这种快速、持久的应激反应,可能对HSP70持续发挥其细胞保护作用具有重要意义。 相似文献
15.
目的 :探讨七氟醚预适应和缺氧预适应对乳鼠心肌细胞热休克蛋白 70表达的影响。方法 :第 2代培养心肌细胞随机分为正常对照组 (C组 )、缺氧 /复氧组 (A/R组 )、缺氧预适应组 (IP组 )和七氟醚预适应组 (S组 ) ,每组均缺氧 2h ,复氧 48h。分别取复氧 0 ,1,12 ,2 4,36和 48h的细胞 ,用免疫组化染色检测HSP70 表达并进行图象分析。结果 :在各个时间点 ,S组和IP组间的HSP70 表达均显著高于A/R组和C组 (P <0 .0 1) ,A/R组的HSP70 表达略高于C组 ,S组和IP组间的HSP70 表达差异无显著性 (P >0 .0 5 )。随着复氧时间的延长 ,S组和IP组间的HSP70 表达从 1h开始增加 ,2 4h表达最强 ,与 1h相比差异具有显著性 (P <0 .0 5 )。结论 :七氟醚预处理和缺氧预处理均可诱导乳鼠心肌细胞HSP70 在延迟相呈高表达 ,提示HSP70 参与了七氟醚预适应和缺氧预适应的延迟保护相。 相似文献
16.
浅低温对犬全脑缺血再灌注后脑组织诱导型热休克蛋白70表达的影响 总被引:1,自引:0,他引:1
目的:研究犬全脑缺血再灌时浅低温对热休克蛋白70(HSP70)表达的影响,探讨热休克蛋白在低温脑复苏中的作用。方法:采用犬心脏停跳再复苏模型。14只犬随机分成三组:非缺血对照组(n=4)、常规治疗组(n=5)和浅低温组(n=5)。用免疫组化测定脑组织内HSP70表达阳性细胞数密度和反应产物灰度值。结果:犬全脑缺血再灌后HSP70表达明显增强(P<0.01)。浅低温组HSP70表达增强比常规治疗组更明显(P<0.01)。病理损伤明显减轻。结论:浅低温能增加再灌脑组织HSP70表达,并可能是低温脑复苏机制之一。 相似文献
17.
An experimental model for canine visceral leishmaniasis 总被引:6,自引:1,他引:5
PEDRO ABRANCHES GABRIELA SANTOS-GOMES NURIT RACHAMIM† LENEA CAMPINO LIONEL F. SCHNUR‡ CHARLES L. JAFFE† 《Parasite immunology》1991,13(5):537-550
Seven mixed-breed dogs were challenged with either promastigotes or amastigotes of Leishmania donovani infantum strains recently isolated from naturally infected dogs. Different routes and numbers of parasites were utilized and each dog was monitored for at least 1 year post-infection. Anti-parasite specific antibody levels were measured by enzyme-linked immunosorbence, immunofluorescence, crossed-immune electrophoresis and Western blotting on crude antigen. Western blotting on two pure parasite proteins, dp72 and gp70-2, was also done. Mitogenic and antigen-specific stimulation of peripheral blood lymphocytes was monitored; and the haematological, clinical and parasitological parameters measured. Dogs challenged with amastigotes exhibited a more pronounced humoral response to leishmanial antigens. Only in one case was strong antigen-specific proliferation detected. Clinical signs of disease, including hypergammaglobulinaemia, enlarged lymph nodes and the presence of parasites, were also more apparent in the dogs challenged with amastigotes. None of the seven dogs died. Serum antibodies to leishmanial antigens were apparent between 1.5 to 3 months following challenge and correlated with the appearance of enlarged lymph nodes, hypergammaglobulinaemia and the presence of parasites in tissue biopsies. Serum antibodies remained chronically high in these dogs throughout the period of the study. Only one dog (1/3) challenged intravenously with promastigotes and the dog challenged intradermally with amastigotes produced transient antibody responses to leishmanial antigen. 相似文献
18.
Shunichi Takaya MD Shunzaburo Iwatsuki Takashi Noguchi Hisaaki Koie Iman Zaghloul Raman Venkataramanan Thomas E. Starzl 《Surgery today》1989,19(1):49-56
The influence of experimentally induced hepatic dysfunction on the pharmacokinetics of Cyclosporine A (CsA) was determined
in dogs. The pharmacokinetics of oral (PO) and intravenous (IV) CsA were studied before and after 70 per cent hepatectomy
or complete bile duct ligation (CBDL). Changes in liver function were monitored by serial measurements of serum bilirubin,
and by the maximum removal rate (Rmax) and plasma disappearance rate (ICG-K) of indocyanine green (ICG). Concentrations of
CsA in whole blood were measured by HPLC. Seventy per cent hepatectomy caused significant liver dysfunction: the ICG-Rmax
decreased by 47.7±7.1 per cent (mean±SD) and the ICG-K decreased by 61.3±9.7 per cent during the first week after hepatectomy.
At the same time, the systemic clearance (CLs) of IV-CsA decreased by 43.9±8.2 per cent, the area under the concentration
curve (AUC) of IV-CsA increased by 35.4±20.8 per cent and the bioavailability of CsA decreased by 26.4±14.8 per cent. CBDL
also induced significant liver dysfunction: the ICG-Rmax decreased by 39.1±12.8 per cent and the ICG-K decreased by 65.6±3.6
per cent in the second week after the operation. During the same period, the AUC of PO-CsA decreased by 69.9±10.7 per cent
and the bioavailability of CsA also decreased markedly by 73.9±15.6 per cent. These data indicate that hepatic impairment
significantly influences the pharmacokinetics of CsA, not only by the changes in intestinal absorption, but also by those
in hepatic, metabolism. Dose adjustment is therefore necessary in the presence of hepatic dysfunction in order to maintain
an adequate blood concentration of CsA without causing side effects.
This research was performed in the Department of Surgery, University of Pittsburgh Health Center, University of Pittsburgh,
USA 相似文献
19.
目的:探讨沙漠热环境负重行军血淋巴细胞HSP70的变化规律。方法:对沙漠干热环境中以不同速度和时间负重行军的54名战士和14名对照血淋巴细胞HSP70进行对比分析。结果:相同行军时间的不同行军速度间淋巴细胞HSP70有显性差异(P<0.05);3.5km/h行军3h组淋巴细胞HSP70明显高于对照和行军2h组(P<0.05):5.0km/h行军1.2h组血淋巴细胞HSP70明显高于对照和行军3h组(P<0.05)。结论:随行军速度和时间的增加,淋巴细胞HSP70增高;当行军速度和时间达到一定水平后,机体淋巴细胞HSP70明显增加。血淋巴细胞HSP70作为热损伤和热耐受的监测指标较血浆HSP70敏感。 相似文献
20.