PILOT--INVASION REGULATED BY FIBRONECTIN AND RECEPTORS

细胞外基质是肿瘤细胞侵袭和迁移的重要调控成分。具体来说，纤维连接蛋白（FN）的V区选择性剪接对这些进展很重要，因为只有含有该区域的FN微小蛋白（V+H和V+H-）在体外诱导鳞状细胞癌（SCC）细胞的侵袭和迁移增加。相比之下，当V+H-FN蛋白处理时，原代正常角质形成细胞和成纤维细胞发生凋亡。在成纤维细胞中，这种机制是由硫酸软骨素蛋白聚糖介导的，可能是由α - 4整合素介导的，可能是由caspase-1和-3介导的caspase级联，p53和c-myc的改变以及pp125 FAK的降低介导的。这些数据表明，致瘤性使SCC细胞绕过凋亡途径，在V+H-蛋白的作用下呈现侵袭性和迁移性表型。据推测，SCC细胞对V+H-蛋白的反应增加了迁移表型。假设SCC细胞通过细胞表面蛋白聚糖和整合素受体对FN的V区选择性剪接做出反应，从而增加了细胞的侵袭和迁移，这两种受体启动的信号转导途径不同于初级非转化受体，后者启动的信号转导途径不同于初级非表面受体，参与介导含有V的FN片段诱导的迁移和侵袭的增加。具体来说，确定硫酸皂素蛋白聚糖和α 4整合素是否参与了这种侵袭和迁移机制，因为这些受体调节了成纤维细胞中含有v的FN片段引发的凋亡途径。(2)研究含v的FN片段介导SCC细胞迁移和侵袭增加的信号反应。具体来说，确定p53和c-myc是否像在原代细胞中一样被调节。这些研究将有助于解释细胞-基质相互作用的一些基本机制和调节肿瘤细胞生物学的信号机制。此外，由于鳞状细胞癌是最常见的恶性口腔肿瘤类型，占口腔癌相关死亡的主要部分，这些研究可能为治疗干预提供潜在有用的途径。

The extracellular matrix is an important regulatory component of tumor cell invasion and migration. Specifically, the alternatively spliced V region of fibronectin (FN) is important to these progresses since only FN miniproteins (V+H and V+H-) containing this region induce increased invasion and migration of squamous cell carcinoma (SCC) cells in vitro. In contrast, primary normal keratinocytes and fibroblasts undergo apoptosis when treated with the V+H-FN protein. In fibroblasts, this mechanism is mediated by chondroitin sulfate proteoglycans, possibly by the alpha 4 integrin, by a caspase cascade involving caspase-1 and -3, by alterations in p53 and c-myc, and by a concomitant decrease in pp125 FAK. These data suggest that tumorigenicity has enabled SCC cells to bypass the apoptotic pathway and instead take on an invasive and migratory phenotype in response to the V+H- protein. It is hypothesized that SCC cells undergo increased migratory phenotype in response to the V+H- protein. It is hypothesized that SCC cells undergo increased invasion and migration in response to the alternatively spliced V region of FN via cell surface proteoglycan and integrin receptors, which initiate a signal transduction pathway that differs from that in primary non- transformed receptors, which initiate a signal transduction pathway that differs from that in primary non-surface receptor(s) involved in mediating increased migration and invasion induced by the V-containing FN fragments. Specifically, determine whether condroitin sulfate proteoglycans and the alpha4 integrin are involved in this mechanism of invasion and migration, since these receptors regulate the apoptotic pathway triggered by the V-containing FN fragment in fibroblasts. (2) Examine the SCC cell signaling response involved in mediating increased migration and invasion induced by the V-containing FN fragments. Specifically, determine whether p53 and c-myc are modulated as in the primary cells. These studies will help explain some of the basic mechanisms underlying the cell-matrix interactions and signaling mechanism that regulate tumor cell biology. In addition, since squamous cell carcinoma is the most common type of malignant oral neoplasm, accounting for a major portion of deaths related to oral cancer, these studies may provide potentially useful avenues for therapeutic intervention.