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The genetic program that drives tumor metastasis and the mode and timing of its initiation are of great practical significance to clinical management. Modern technical advances open new opportunities for gaining useful relevant information. Gene expression profiles of histologically‐verified viable tissue from lymph node metastases were compared with those of matched primary breast cancers from 10 different patients, among samples from over 400 cases, using high‐throughput oligonucleotide arrays comprising probes for 22,000 genes. It was observed that metastases have very similar expression signatures to their parent tumors. However, detailed computational analysis revealed that a small number of genes were consistently differentially expressed between 100% of tumors and metastases, suggesting that these are mechanistically important. Lists of such candidate genes, of potential clinical interest, are provided. We interpret these results in the framework of a meta‐analysis of previous investigations by others and ourselves and of existing clinical knowledge on the behavior of human tumors. The collective data show that metastases resemble their primary tumors but the signatures obtained in different studies are not sufficiently reproducible or informative to be prognostically useful, although they do give valuable insights into the pathogenesis and biology of human tumor metastasis. The findings indicate that the genetic program encoding metastasis is implemented progressively over time although, occasionally, this evolution can occur rapidly, early in the life of the neoplasm. The important clinical significance of this deduction is that, in most patients, early detection provides time for appropriate therapeutic intervention to be effective in obstructing metastasis. 相似文献
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CD44分子属于黏附分子家族中的一员,其CD44的异常表达与乳腺癌的发生、发展和转移密切相关。近年来研究表明乳腺癌干细胞表面高度表达CD44分子,针对CD44分子与乳腺癌干细胞关系的研究,将为乳腺癌的临床治疗提供新的靶点。 相似文献
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Choroid plexus papillomas (CPPs) are typically considered as benign tumors, with a favorable long-term prognosis. Drop metastasis of CPP into the spinal subarachnoid space is rare. We report a 42-year-old woman who presented with headache and back pain 6 years after removal of a posterior fossa CPP. Magnetic resonance imaging revealed mass lesions in the lumbosacral subarachnoid space and recurrent intracranial tumor. The lesions were resected and histologically diagnosed was CPP. We consider that CPP can spread via cerebrospinal fluid pathways and cause spinal drop metastasis. Therefore, it is necessary to evaluate the whole spinal axis and to perform periodic follow-up examinations in patients with CPP. 相似文献
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内乳淋巴结在乳腺癌治疗中的重要性 总被引:2,自引:0,他引:2
目的探讨乳腺癌术后内乳淋巴结复发的原因,强调内乳淋巴结在乳腺癌治疗中的重要性。方法回顾性分析40例以内乳淋巴结转移为首先复发的女性乳腺癌患者的临床资料、初发病时的临床特征、手术方式、术后病理分期以及治疗经过。结果40例患者内乳淋巴结复发与患者年龄、经期状况、手术方式无关(P>0.05)。而与原发肿瘤直径、部位、腋窝淋巴结阳性数、临床病理分期相关(P<0.05)。结论位于乳腺内侧区、中央区的大块肿瘤(>3cm),腋窝淋巴结阳性数多(>3),且临床病理分期晚(IIb IIIab)的乳腺癌患者,内乳淋巴结转移机率较高,须加强术后综合治疗。 相似文献
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目的探讨口腔鳞状细胞癌颈淋巴转移范围和临床病理因素间的关系。方法对26例已存在颈淋巴转移的原发口腔癌患者,进行颈淋巴转移范围和患者的临床病理资料的统计分析,寻找影响转移范围的主要因素。结果单因素分析发现,肿瘤生长方式和分化程度与转移范围相关。多因素分析显示,肿瘤生长方式(浸润型)和肿瘤转移范围相关。结论对颈淋巴已有转移的口腔癌患者,若原发灶为浸润性生长,肿瘤倾向于更大范围的转移。对已有颈淋巴转移的口腔癌患者,颈淋巴清扫术范围的制定,主要考虑肿瘤生长方式,适当考虑肿瘤发病部位、厚度、大小和细胞的分化程度,可以不考虑患者年龄和性别。 相似文献
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We report a rare case of advanced renal cell carcinoma in apatient who showed complete resolution of metastases to thelung and bones after nephrectomy, partial jejunectomy and subsequentalpha-interferon therapy. The patient was a 54-year-old manwhose right lung and left femur metastases were detected beforenephrectomy. In the seventh week after nephrectomy, a partialjejunectomy was carried out because of the obstructive ileuscaused by intraluminal multiple metastases of the jejunum. Apathological fracture of the metastasized right humerus occurredsubsequently. After four months of intramuscular alpha-interferonadministration (3x106 units/day), however, x-rays revealed thecomplete disappearance of the metastatic lung shadow and a solidunion of the humerus, and there were no tumor cells in the femurspecimen resected at the subsequent reconstruction surgery ofthe left leg. Seven years have passed from onset, and the patientis still alive and disease free. 相似文献
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肿瘤转移相关蛋白在甲状腺乳头状腺癌伴淋巴结转移组织中的原位表达研究 总被引:1,自引:0,他引:1
利用免疫组化ABC法,研究甲状腺乳头状腺癌,甲状腺腺瘤和正常甲状腺组织中的肿瘤转移相关基因蛋白CD44v6,EGFR,转移抑制基因nm23-H1和抑癌基因p53蛋白的原位表达。结果发现CD44v6和EGFR表达上调与肿瘤转移密切相关(P<0.05,P<0.01),而nm23-H1的表达与肿瘤转移抑制密切相关(P<0.01)。这提示肿瘤转移相关基因和转移抑制基因之间的表达失衡是甲状腺乳头状腺癌易发生转移的重要原因。 相似文献
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Reduced Expression of nm23 Is Associated with Metastasis of Human Gastric Carcinomas 总被引:7,自引:0,他引:7
Reduced expression of nm23 gene is implicated in high metastatic potential In a variety of malignancies. To elucidate the role of nm23 in human gastric carcinomas, we examined loss of heterozygosity (LOH) of nm23 gene by Southern blotting, nm23 mRNA expression by Northern blotting and nm23 protein expression by Western blotting as well as immunohistochemistry in both primary and metastatic tumors. LOH of nm23 gene was found in 2 (8%) out of the 23 informative gastric carcinomas. Twenty-two (84%) out of the 26 cases expressed nm23 mRNA at higher levels in primary tumor tissue than in corresponding non-neoplastic mucosa. No obvious correlation was observed between clinico-pathological features and LOH of nm23 gene or nm23 mRNA expression. On the other hand, 52% of the gastric carcinomas showed reduction of nm23 immunoreactivity in the metastatic tumor of regional lymph nodes, as compared to the primary tumor. Interestingly, 71% of the gastric carcinomas showed weaker nm23 immunoreactivity in the liver metastasis than in the primary tumor. These results suggest that nm23 overexpression is linked with development of gastric carcinomas and the decrease in expression of nm23 participates in metastasis. 相似文献