Gene Diagnosis/Therapy of Oral Cancer Targetted for Autocrine Growth Factor and Angiogenic Factor Genes

血管生成是肿瘤发生的必要先决条件。肿瘤血管生成受多种血管生成因子的调控。在目前发现的几种血管生成因子中，肝素结合生长因子FGF-2被认为是最有可能诱导肿瘤血管生成的候选因子。肝素结合蛋白17 （HBp17/FGF- bp）是FGF家族中一个17kda的新型结合蛋白。这种结合蛋白以非共价和可逆的方式与HBGFs结合。HBp17与FGF-2结合可介导固定FGF-2从细胞外基质释放。因此HBp17以旁分泌方式参与血管生成。本研究采用免疫组化技术，在口腔正常黏膜、不同程度发育不良及鳞状细胞癌组织中观察到FGF-2和HBp17的共定位。FGF-2和HBp17的表达评分随着上皮异常增生的严重程度而升高，在严重异常增生中表达评分最高，且两者之间具有高度相关性(P=0…045)在口腔肿瘤发生的所有阶段。FGF-2和HBp17的表达也与MVD有显著相关性（P=0.045）。但与TNM分期及复发时间无相关性（P < 0.05）。我们的研究结果表明，血管生成因子FGF-2和HBp17可能为诱导肿瘤血管生成提供相同的必要调节信号。肝素结合血管生成因子（FGF-2和HBp17）和MVD在严重非典型增生阶段的最高表达评分提示了新型抗血管生成治疗策略的潜在靶点。我们通过RT-PCR研究了两种FGFR3变体FGFR3- iiib和FGFR3- iiic在口腔鳞状细胞癌和正常口腔上皮细胞中的转录水平。正如预期的那样，FGFR3-IIIb变体是上皮谱系的特征，是唯一在恶性和非恶性上皮组织中表达的形式。我们对71例OSCC样本的FGFR3编码区进行了PCR-SSCP分析。异常迁移带序列显示71例OSCC中有44例（62%）存在单核苷酸取代。G697C突变在受体的第二激酶区域产生半胱氨酸残基。FGFR3目前似乎是口腔鳞状细胞癌中最常见的突变癌基因：在60%以上的病例中发生突变。FGFR3似乎介导相反的信号，作为骨生长的负调节因子，并在几种肿瘤类型中作为致癌基因。少

Angiogenesis is an essential pre-requisit for tumorigenesis.Tumor angiogenesis is regulated by many angiogenic factors. Among the several angiogenic factors identified to date, heparin binding growth factor FGF-2 has been regarded as the most likely candidate for the induction of tumor angiogenesis. Heparin binding protein 17 (HBp17/FGF-BP) is a 17 KDa novel binding fox FGF family. This binding protein binds with HBGFs in a non-covalent and reversible manner. Binding of HBp17 with FGF-2 mediates the release of immobilized FGF-2 from the extracellular matrix. Thus HBp17 participates in angiogenesis in paracrine manner. In this study by using immunohistochemical technique co-localization of FGF-2 and HBp17 was observed in oral tissues including normal mucosa, dysplasia of different degrees and squamous cell carcinoma (SCC). The expression score for FGF-2 and HBp17 became higher with the severity of epithelial dysplasia and highest in severe dysplasia and had high correlation between (P=0 … More .045) at all stages of oral tumorigenesis. The expression of FGF-2 and HBp17 also showed significant association with MVD (P=0.045). But it did not correlate with TNM stages or recurrence interval (P>0.05). Our results demonstrated that angiogenic factors FGF-2 and HBp17 might provide the equal essential regulatory signals needed for the induction of tumor angiogenesis. The highest expression score of heparin binding angiogeric factors (FGF-2 and HBp17) and MVD in the severe dysplasia stage indicated the potential point of target for novel anti-angiogenic therapeutic strategies.We have studied transcript levels of the two FGFR3 variants, FGFR3-IIIb and FGFR3-IIIc by RT-PCR in oral squamous cell carcinomas and normal oral epithelial cells. As expected, the FGFR3-IIIb variant, characteristic of the epithelial lineage, was the only form expressed in both malignant and non-malignant epithelial tissues. We performed PCR-SSCP analysis of the coding region of FGFR3 of 71 OSCC samples. The sequences of abnormally migrating bands revealed single nucleotide substitution in 44 of 71 OSCC (62%). G697C mutation create cysteine residue in the 2nd kinase domain of the receptor.FGFR3 currently appears to be the most frequently mutated oncogene in oral squamous cell carcinomas : it is mutated in more than 60% of cases. FGFR3 seems to mediate opposite signals, acting as a negative regulator of growth in bone and as an oncogene in several tumor types. Less