Relationship of cellular adhesive molecules and angiogenesis with oral squamous cell carcinoma.

e -钙粘蛋白表达的缺失已被证明与许多类型癌症的侵袭和转移有关。我们从口腔鳞状细胞癌（SCC）中建立了E-cadherin阳性（HOC719-PE）和阴性（HOC719-NE）克隆。HOC719-PE细胞表现为上皮形态，细胞膜表达E-cadherin，而HOC719-NE细胞表现为成纤维形态，细胞膜不表达E-cadherin。在侵袭实验和三维培养中，HOC719-NE细胞的侵袭能力明显高于HOC719-PE细胞。这些细胞表达了相似水平的a-连环蛋白和b-连环蛋白mrna。然而，HOC719-NE细胞，而不是HOC719-PE细胞，强烈表达螺，这是一种参与上皮细胞向间充质表型分化的转录因子。在其他SCC细胞中进一步观察到蜗牛和E-cadherin的反向表达，包括HOC313和我们之前报道的未表达E-cadherin蛋白的TSU细胞。结果表明，蜗牛的表达对于获得更多侵袭性和转移性SCC表型具有关键作用，我们在这里报道的克隆将为理解上皮细胞向间充质SCC细胞转变的机制提供有用的工具。血管生成是指现有血管系统的新生血管。血管生成在肿瘤生长和转移中的重要性已被描述。人们认为抑制血管生成可以抑制肿瘤的生长和转移。在这些概念的基础上，人们研究了许多抗血管生成药物，使用抗血管生成药物进行新的化疗是有希望的。在这项研究中，我们展示了口腔鳞状细胞癌（SCC）细胞衍生的条件培养基的血管生成活性和几种已知诱导这些细胞血管生成的生长因子的表达。然后，我们研究了最有希望的抗血管生成药物之一TNP-470对严重联合免疫缺陷（SCID）小鼠和培养的口服SCCs生长的影响。tnf -470可抑制SCID小鼠皮下接种的口腔SCC细胞HSC-2的生长，并呈剂量依赖性。免疫组织化学观察到TNP-470治疗后癌组织周围微血管减少。在高剂量（50mg/kg） TNP-470治疗期间，除了短暂的体重减轻外，未观察到明显的副作用。tnf -470对22种细胞均有抑制作用，包括7种口腔SCC细胞，12种其他癌细胞、成纤维细胞、正常上皮角质形成细胞和内皮细胞。然而，内皮细胞对TNP-470的敏感性比其他细胞高1000倍以上。tnf -470对内皮细胞和口腔SCC细胞均有诱导细胞周期阻滞的作用，但SCC细胞所需的浓度是内皮细胞的1000倍。使用[^3H]-TNP-470结合实验显示，内皮细胞和其他细胞之间TNP-470受体的数量和亲和力没有显著差异。在内皮细胞和其他细胞中发现了类似水平的蛋氨酸氨基肽酶2（MetAP-2）基因表达，TNP-470已被报道与之结合。这些结果表明，tnf -470等抗血管生成药物治疗口腔癌可能是一种有效的新疗法，并提示tnf -470对内皮细胞的特异性抑制可能不是由于其受体数量和对tnf -470的亲和力较高，而是由于tnf -470的特异性靶分子的存在。少

The loss of E-cadherin expression has been shown to correlate to the invasion and metastasis of many types of carcinomas. We estab Iished E-cadherin positive(HOC719-PE)and negative(HOC719-NE)clones from an oral squamous cell carcinoma(SCC). HOC719-PE cells showed epithelial morphology with E-cadherin expression in the cell membrane, whereas HOC719-NE cells demonstrated fibro blastic morphology without E-cadherin expression. In invasion assay and three dimensional culture, HOC719-NE showed much higher invasivce ability than HOC719-PE cells. These cells expressed similar levels of mRNAs for a- and b-catenin. However, HOC719-NE cells, but not HOC719-PE cells, showed strong expression of snail, a transcription factor implicated in the di erentiation of epithelial cells into mesenchymal phenotype. This reverse expression of snail and E-cadherin was further observed in other SCC cells including HOC313, and TSU cells that we previously reported to show no expression of E-cadherin protein. The … More se results indicated that the expression of snail has a key role for the acquisition of more invasive and metastatic phenotypes of SCC and the clones we reported here will be useful tools for understanding the mechanism of the transition from epithelial to mesenchymal SCC cells.Angiogenesis refers to neovascularization from the existing vascular system. The importance of angiogenesis in cancer growth and metastasis has been described. It is thought that inhibition of angiogenesis will result in the inhibition of cancer growth and metastasis. On the basis of these concepts, many anti-angiogenic agents have been investigated and new chemotherapies using anti-angiogenic agents are promising. In this study, we showed the angiogenic activities of conditioned media derived from oral squamous cell carcinoma(SCC)cells and expression of several growth factors which are known to induce the angiogenesis in these cells. Then, we examined the effects of TNP-470, one of the most promising anti-angiogenic agents, on the growth of oral SCCs in severe combined immunodefi cient(SCID)mice and inculture.The growth of oral SCC cells, HSC-2, inoculated subcutaneously in SCID mice was inhibited in a dose dependent manner by the treat ment with TNP-470. A reduction of microvessels surrounding cancer tissue treated with TNP-470 was observed by immunohistochemistry. Significant side effects were not observed except for the transient weight loss during the period of treatment with high dose(50mg/kg)of TNP-470. TNP-470 inhibited the growth of all of the 22 kinds of cells including 7 oral SCC cells, and 12 other cancer cells, fibroblasts, normal epithelial keratinocytes and endothelial cells. However, the sensitivity of endothelial cells to TNP-470 was more than 1000 times higher than those of all other cells. G _1arrest on cell cycle was induced both in endothelial cells and oral SCC cells by the treatment with TNP-470, although 1000 times more concentration was needed for SCC cells compared with endothelial cells. Binding assay using[^3H]-TNP-470 revealed that there were no significant differences of numbers or affinities of receptors for TNP-470 between endothelial cells and othercells. Similar levels of the gene expression of methionine aminopeptidase 2(MetAP-2), which TNP-470 has been reported to bind, was seen in the endothelial cells and other cells.These results indicated that the treatment with anti-angiogenic agents such as TNP-470 may be effective as a new therapy for oral cancer and suggested that the specific infibition of endothelial cells by TNP-470 may be not due to the higher receptor number and affinity for TNP-470, but due to the existence of specific target molecules of TNP-470. Less