A study of cytokeratin in human normal bladder epithelium and bladder carcinoma cell lines

ヒト正常膀胱上皮細胞および膀胱腫瘍細胞において, 細胞骨格の構成要素であるサイトケラチンの形態を抗ケラチンモノクローナル抗体を用いた免疫蛍光法により検討した.正常膀胱上皮のサイトケラチンは細い均一な太さの線維で, 細胞質内を直線状に走り, かつ均等に分布していたが, 腫瘍細胞では, サイトケラチンに太さの大小不同, 蛇行, 細胞内分布の不均等などの変化が認められた.各膀胱腫瘍継代培養細胞のヌードマウス移植における組織学的形態とサイトケラチンの形態変化とを対比し, 膀胱腫瘍細胞の組織学的悪性度とサイトケラチン線維の変化の強さとが比較的併行している所見を得たNormal epithelial and carcinoma cells of human bladder were investigated for the cytokeratin which is one of the intermediate filaments and comprises cytoskeleton using the immunofluorescence method. Carcinoma cell lines used were JTC-30, JTC-32, HUB-41 and T-24. In normal urothelium, keratin fibers were fine and straight with unchanged diameter and distributed regularly in the cytoplasm. By contrast, keratin fibers in bladder carcinoma cells were kinked and changed in diameter and were distributed irregularly in the cytoplasm. The above findings were most obvious in T-24 which formed undifferentiated carcinoma when transplanted to nude mice, and keratin fibers were dominantly located in the perinuclear area. The changes of keratin fibers appeared to be parallel to the grade of histological anaplasia of the tumor formed by implantation of bladder carcinoma cell line cells to nude mice. These observations suggest that the morphology of cytokeratin is a useful indicator for evaluating the grade of malignancy in transitional cell carcinoma