The present invention improves the extremely simple and less invasive therapy that does not cause serious side effects and radiation exposure by the agent and attacks the tumor cells, and is used for therapy that enables radical cure. The purpose is to provide an agent. According to the present invention, by utilizing the EPR effect specific to tumor cells, the tumor cells are covered with the tissues by fine particles that permeate only the tumor blood vessels and accumulate and settle in the tumor, and do not release the angiogenesis inducing factor. After passing through the gap between 50 nm to 500 nm of tumor vascular endothelial cells, which does not separate and move the tumor cells with improved motility in the oxygen state, and adheres to the tumor cells and extracellular matrix near the gap, Provided is a tumor sealant characterized by biodegradation.本発明は、剤による重篤な副作用や放射線被爆がなく、腫瘍細胞を兵糧攻めにするという極めてシンプルで侵襲性の低い療法を改善して、根治を可能とする療法に使用される腫瘍封止剤を提供することを目的とする。本発明によれば、腫瘍細胞に特異的なＥＰＲ効果を利用し、腫瘍血管のみを透過し腫瘍に集積し定着する微粒子により腫瘍細胞を組織ごと覆い、血管新生誘導因子を放出させず、また低酸素状態で運動性が向上した腫瘍細胞も分離して他の場所へ移動させない、５０ｎｍから５００ｎｍの腫瘍血管内皮細胞の間隙を透過し、該間隙近くの腫瘍細胞及び細胞外マトリックスに付着した後、生体内分解することを特徴とする腫瘍封止剤を提供する。
