“pre-linitis”状態における癌細胞の特性―癌細胞の粘液形質ならびに細胞増殖活性

Mucinous Phenotype and Activity of Cell Proliferation in the Linitis-type of Gastric Cancer Cell

要旨　linitis型の増殖因子とそのレセプターに関する検討，更に，粘液形質に関する検討を免疫組織学的に行い，“pre-linitis”状態について言及した．その中で，"pre-linitis"状態として胃底腺領域にできるⅡc-like型あるいはMénétrier型のsm massiveからmp癌が，linitis型の初期変化として重要であることと，線維化の完成にTGF-βRIIの異常と癌細胞の粘液形質からみた脱分化が関与することを示したが，今回，われわれが分類したlinitis型が必ずしも中村の指摘するlinitis plasticaと同じであるとは言えない．われわれが示した体部領域にびまん性に浸潤するlinitis型もまた，中村の定義するlinitis plasticaへの道のmile stoneあるいはその一部を見ているのかもしれない．今回の検討結果は，そういう可能性も含んだ中で，体部領域に拡がる硬化型びまん性癌と潰瘍型癌とを両極に組織学的に細分類し，両者の同質性と異質性をみたものにすぎないと考えている．

　The aim of the present study was to describe the prelinitis states in gastric cancer. Therefore, we tested immunohistochemical staining for transforming growth factor-β (TGF-β), its receptor, and mucinous phenotype using immunohistochemistry. In addition, we determined the definition of linitis-type gastric cancer according to Nakamura's reports in which it is thought to be derived from ulcer-negative lesion in the fundic gland area. Its histological character was poorly differentiated adenocarcinoma and signet-ring cell carcinoma (undifferentiated type: por2) with diffuse invasion and dense fibrosis transmurally.

　The ratio of TGF-β to TGF-β type Ⅱ receptor (TGF-β RII) was low in Ⅱc-like type and Ménétrier type advanced gastric cancer in the fundic gland area. This result was similar to that found in linitis-type gastric cancer. Therefore, Ⅱc-like type and Ménétrier type of gastric cancer in the fundic gland area may be considered as one of the pre-linitis states of gastric cancer. The mutation of TGF-βRII had a bearing on the formation of dense fibrosis and varied dedifferentiation in linitis-type gastric cancer.

　We concluded that a close association might exist between evolution of initis-type gastric cancer and TGFβ RII mutation, and dedifferentiation and transforma-tion of mucinous phenotype might also be given rise to as a consequence.