Identification and early detection of oral cancer by the use of anti-EGF-receptor monoclonal antibody.

近年来，关于肿瘤发生机制的研究表明，生长因子受体的功能障碍可能是导致细胞生长异常的关键。事实上，许多癌基因编码的受体蛋白，和特定的上调或下调的生长因子，如表皮生长因子（EGF）的受体已被可视化在致癌过程中，目前的研究一直集中在建立工作的检测方法，定量的EGF受体作为一个有用的标志物细胞膜内的群体的特异性增加上皮肿瘤。本方法利用特异性的抗EGF受体单克隆抗体进行强化，可望保证临床早期检测（IgG#528），由Dr.T.Kawamoto首先制备，最终建立的方法是基于亲和素-生物素比色反应，而不使用放射性同位素，如125-但在准确度和灵敏度方面与常规放射免疫分析法相当。从100 mg湿重的肿瘤组织样品开始，本方法能够通过因子2来表示和定量受体群体的可估计差异，而以前在组织切片水平的组织化学判断中为10-100。此外，该方法是简单和快速进行。在实验室条件下，100个样本的检测可在一天内完成，该方法现已成功应用于包括口腔上皮肿瘤在内的多个样本的检测，并被认为是有用的早期检测。该方法在准确性和灵敏度方面的改进有望满足早期发现肿瘤和建立受体水平与肿瘤恶性程度或转移水平之间的工作相关性的要求。

Recent view on oncogenic mechanism assigns the malfunction of growth factor- receptors as possible key to induce an anomalous control of the cellular growth. In fact, a number of oncogenes code receptor proteins, and specific up or down regulation of the receptors for growth factors such as epidermal growth factor(EGF) has consequently been visualized during oncogenic processes.The present research has been focused on establishment of the working assay method quantitating the specific increase of intramembrane population of EGF receptor as an useful marker for epithelial tumors. The clinical early detection is expected to be assured when fortified by the present method utilizing specific anti-EGF receptor monoclonal antibody(IgG #528) as first prepared by Dr.T.Kawamoto, one of the investigators.The method finally established is based on the avidin-biotin colorimetric reaction without employing radioisotope such as 125-I but comparable enough to the conventional radioimmunoassay method in respect of the accuracy and the sensitivity. Starting with tumor tissue sample of 100 mg wet weight, the present method is capable of signifying and quantitating the estimable difference of the receptor population by the factor 2, compared to 10-100 in the former histochemical judgement in the tissue slice level. Furthermore, the method is simple and rapid to carry out. Assay for 100 samples can be completed within one day in facilitated laboratory conditions.The method has now been successfully applied for a number of samples including oral epithelial tumors and considered to be useful for the early detection. The hopeful improvement of the method in raising both the accuracy and the sensitivity could meet the requirement to detect the tumors in much earlier stage and to estblish the working corelation between the assayed receptor level and the tumor malignancy or the metastasis level.