抄録
Immunohistochemical localization of E-cadherin, α-catenin, β-catenin, integrin α6 and laminin was compared in highly metastatic hamster squamous cell carcinomas termed O-1N. The tumors grew expansively until 4 weeks (expansive stage) and later showed diffuse invasion and induction of stroma which was rich in vascular vessels (invasive stage). Vascular invasion by tumor cell nests was encountered most often in the middle zone at the invasive stage. The size of tumor cell nests remained small in the peripheral zone in all periods, whereas it was significantly larger in the middle and central zones. E-cadherin and laminin expressions were reduced in the periphery, but not in the middle zone. Tumor cell nests penetrated into the vascular lumen without losing expression of adhesion molecules. The results indicate reduced expression of adhesion molecules could be a sign for high invasive and metastatic potency of a tumor, but it is not an essential prerequisite for vascular invasion.
