Obama H, Obama K, Takemoto M, Soejima Y, Shirahama T, Ohi Y, Yoshida H, Qzawa M, Muramatsu T, Maruyama I
Department of Biochemistry, Kagoshima University, Japan.
Anticancer Res. 1999 Mar-Apr;19(2A):1143-7.
Thrombomodulin (TM) is an endothelial thrombin receptor which acts as a natural anticoagulant through inactivation of the procoagulant activity of thromin. In the present study, we demonstrated that TM is expressed on the urinary bladder epithelium. The cell line BOY established from human transitional cell carcinoma of the urinary bladder also expressed the TM message (3.7kb). These cells express an 85 kDa TM protein which is identical in size to that of MEG-01, a human megakaryoblastic cell line, reported previously. We also ascertained the expression and localization of TM in the human urinary bladder by immunohistochemical staining. TM was localized in the membranes of the transitional epithelium and the cytoplasmic region of umbrella cells. The expression of TM in the transitional epithelium increased with worsening pathological status of cystitis. Based on these results, we concluded that TM is expressed in the urinary bladder. Further, soluble TM in urine may be partially derived from the urinary bladder. At present, the physiological significance of TM expression in the urinary bladder remains to be elucidated.
血栓调节蛋白（TM）是一种内皮凝血酶受体，它通过使凝血酶的促凝活性失活而发挥天然抗凝剂的作用。在本研究中，我们证明TM在膀胱上皮细胞中表达。从人膀胱移行细胞癌建立的细胞系BOY也表达TM信息（3.7kb）。这些细胞表达一种85kDa的TM蛋白，其大小与先前报道的人巨核母细胞系MEG-01的TM蛋白相同。我们还通过免疫组织化学染色确定了TM在人膀胱中的表达和定位。TM定位于移行上皮细胞膜和伞细胞的细胞质区域。随着膀胱炎病理状态的恶化，移行上皮中TM的表达增加。基于这些结果，我们得出结论，TM在膀胱中表达。此外，尿液中的可溶性TM可能部分来源于膀胱。目前，TM在膀胱中表达的生理意义仍有待阐明。
