Specific chemotherapy for pancreato-biliary tract cancer with conjugate of anti-neural cell adhesion molecule antibody and anticancer drug

本研究的目的是为神经细胞粘附分子（NCAM）阳性的胰胆管癌的神经浸润发展一种特异性的化疗方式。采用溴化氰法将抗癌药物丝裂霉素C（MMC）与抗NCAM单克隆抗体（MoAb）共价结合形成偶联物。与相同浓度的MMC溶液相比，偶联物的细胞毒活性保持在66%至95%。偶联物与NCAM阳性胆管癌细胞的结合活性与三种抗NCAM单抗的结合活性相当。因此，本研究制备的偶联物似乎是一种潜在的有用工具，用于针对具有NCAM表达的胆道癌的免疫靶向特异性化疗。为了研究偶联物对肿瘤的分布和抗癌活性，用免疫组织化学染色检测了人肿瘤、胆管细胞癌、胆管癌和胆管癌的NCAM表达。（CCC-1、CCC-2）和胆管癌（TGGK、GGK）的裸鼠移植瘤模型。然而，未检测到NCAM表达。用抗NCAM单克隆抗体与抗鼠IgG抗体偶联后，用流式细胞术检测NCAM抗原的表达，结果显示：在人肝癌细胞系HUCCT 1、HUH 28中，NCAM的表达水平均不明显（胆管细胞癌），PK-1，PK-9为进一步研究NCAM基因在胰腺癌、CaR-1、RCM-1中的表达，需要建立稳定的NCAM阳性胰腺癌细胞系。

The aim of this study was to develope a specific chemotherapy modality for the perineural invasion of neural cell adhesion molecule (NCAM) positive pancreato-biliary tract cancer. An anti-cancer drug Mitomycin C (MMC) was covalently bound to anti-NCAM monoclonal antibody (MoAb) to form a conjugate using a cyanogen bromide method. The cytotoxic activity of the conjugate was maintained at 66 to 95% compared with the same concentration of MMC solution. The binding activity of the conjugate to the NCAM positive bile duct cancer was proved to be the same level as that of tree anti-NCAM MoAb. The conjugate prepared in this study therefore appeared to be a potentially useful tool for immunotargeting specific chemotherapy against biliary tract cancer with NCAM expression.To investigate the distribution and the anticancer activity of the conjugate to the tumor, NCAM expression was examined with immunohistochemical staining for human cancers, cholangiocellular carcinoma (CCC-1, CCC-2) and bile duct carcinoma (TGGK,GGK) in tumor bearing nude mice. However, NCAM expression was not detected. Expression of NCAM antigen was studied with flow-cytometry by using anti-NCAM MoAb following anit-mouse immunoglobulin G (IgG) antibody coupled with FITC.No significant level of NCAM expression was revealed in several human cancer cell lines including HUCCT1, HUH28 (cholangiocellular carcinoma), PK-1, PK-9 (pancreatic cancer) and CaR-1, RCM-1 (rectal cancer).To proceed this study, stable NCAM positive cancer cell line should be established with transfection of NCAM cDNA into human pancreato-biliary tract cancer cell line.