Relationship between metastasis of canine malignant melanoma and membrane glycoprotein AD-1 (CD 63)

犬恶性黑色素瘤是一种恶性程度较高的肿瘤，具有生长迅速、局部侵袭广、转移早、对化疗和放疗耐药、转移较早等特点。在小鼠中，已知膜糖蛋白AD-1或CD63在原发灶中出现，而在转移灶中消失，因此可能在肿瘤转移的机制中发挥作用。为阐明AD-1在犬恶性黑色素瘤转移中的作用，本实验首先建立了犬恶性黑色素瘤细胞系。建立了4株不同增殖方式和对裸鼠移植能力不同的口腔黏膜和皮肤来源的细胞株，并用其中一株细胞制备了抗AD-1的单抗。结果获得了两种抗体。一种只对黑色素瘤细胞起反应，另一种对黑色素瘤和肥大细胞瘤细胞都有反应，已知这两种细胞含有AD-1。遗憾的是，目前尚不清楚这些抗体是否是AD-1的特异性抗体。这两种抗体被用于手术中获得的自发性犬黑色素瘤组织的组织化学。结果表明，前者对原发灶或转移灶均有反应；在某些标本中，原发灶呈阳性，而在转移灶组织中呈阴性；在其他组织中，原发灶组织呈阳性，原发灶组织呈阴性。这可能表明这种抗凝剂识别一些可能与转移有关的物质，但可能与AD-1无关。这些单抗识别的物质及其在肿瘤转移机制中的作用还需要进一步的研究。

Canine malignant melanoma has been known to be quite malignant with rapid growth, wide local invasion, early metastasis, resistant to chemotherapy and radiotherapy and quite early metastasis. In mice, membrane glycoprotein, AD-1 or CD 63, has been known that it appears in the primary lesion but disappears in the metastatic lesion, therefore may play a role in the mechanism of the tumor metastasis. The purpose of this study is to clarify the role of AD-1 in the metastasis of canine malignant melanoma.In the first experiment, establishment of melanoma cell lines from the canine patients were conducted. Four cell lines originated from the oral membrane and skin with different proliferation manner and transplantability to nude mice were established.Using one of these cells, production of the monoclonal antibody to AD-1 was conducted. As a result, two antibodies were obrtained. One reacted only to melanoma cells and the other reacted to both melanoma and mastocytoma cells, which are known to have AD-1. Unfortunately it is still not demonstrated whether these antibodies are specific to AD-1.These two antibodies were used for the histochemistry of spontaneous canine melanoma tissues obtained at surgery. As a result, the former antibody reacted to either primary or metastatic lesions ; in some specimens, positive in the primary tissues and negative in the metastatic tissues, whereas in other tissues, positive in the metastatic tissues and negative in the primary tissues. This may suggest this antigody recognizes some of the substance which may relate to metastasis, but perhaps not to AD-1 . Further study will be needed to clarify the substance recognized by these monoclonal antibodies and its role in the mechanism of metastasis in this tumor.