Expression Of P27～(Kip1) And CyclinD1 In Bladder Tumor

IntroductionBladder carcinoma is the most common tumor in urinary system, among which transitional cell carcinoma takes about ninety percent. It is liable to relapse and the incidence of it is increasing with years go-ing on. The bladder carcinoma has done greatly harm to peoples' health.With the breakthrough of the study on cell cycle in the recent years, the study about the relation between cell cycle and the onset; development and treatment of the malignant tumor is going deeply into as well. The cyclin and the CDK play very important roles in the cell proliferation, as well as out of control of the cell proliferation is the most prominent characteristics of tumor tissue. The cell cycle regula-tion of the eucaryote depends on the activation of the CDK. Cyclin is the positive regulator which activates CDK and CDK inhibitor (CDKI) is the negative regulator which inactivates CDK. The effects of them on CDK activity control the cell cycle transition. P27kipl is the newly found tumor inhibitor which can inhibit CDK and then inhibit the tran-sition of cell from G1 phase to S phase . The function of P27kipl in cellcycle regulation has aroused extensive attention.The present study is ready to detect the expression of cell cycle dependenting on kinase inhibitor P27kipl and cell cycle protein Dl ( cy-clin Dl) in bladder carcinoma through immunohistochemical method, analyzing the relation between them and the tumor grade or phase, and examing the correlation of the expression of these two proteins in blad-der carcinoma.MaterialsSpecimens come from The Second Affilicated Hospital, China Medical University (2000. 1 -2001. 4), 51 bladder tumor speci-mens , comparation 6 normal bladder specimens, pathologic grade by WHO; I : 12 cases, II : 25 cases, III : 14 cases. Clinical grade by UICC: superficial bladder tumor ( Tis Tl) period 23 cases, invasive bladder tumor (12 ^T4) period 28 cases . P27kipl, CyclinDl come from American Santa Crus company; DAB reagent come from Beijing Zhong Shan Biotechnic co; 10% goat serum from American Zymed company.MethodsUsing S - P method, studying the CyclinDl and P27kipl protein expression of51 bladder tumors and 6 normal bladder specimens, and the relationship between P27kipl and CyclinDl.Results(1) Positive rate of P27kipl in tumor Specimens is 47. 06% , Dif-ferent period positive rate is: Tis Tt69.56% , T2 - T428.57% , P < 0. 05, obvious difference. Grade I - II : 56. 76% , III: 21. 43%. Expression of P27kipl is different between three grades ( P < 0. 05 ). (2) Positive rate of cyclinDlin tumor Specimens is 41.17% , Different period positive rate is: Tis - Tt60.87% , T2 T425.00% , P <0.05, obvious difference. Grade I - II : 51. 35% , III: 14. 29%. Expres-sion of P27kipl is different between three grades ( P <0.05).DiscussionsIn 1994, Polyak et al found an 27KD heat -stable protein in the extraction from silent cell that named P27kipl when they studied the mechanism of intercellular contact inhibition and the stasis of cell cy-cle in G! phase induced by TGF - (3. P27 kipl can inhibit the activity of cyclinE - cdk2 compound, and has a negative regulative effect on cell cycle. The 47% aminoacids of P27kipl are similar to P57s, which lo-cates in the N - terminal and mediates the inhibition to CDK. P27kipl and P21 are homogeneous with 40% of a 60 aminoacids fragment at N -terminal similar to P21 and the structure of exons similar to P21. The N - terminal of P27kipl has a 23 aminoacids C - terminal expan-ding region which consists of the same parts with CDK phosphoration. It takes effects in feedback regulation through its target enzyme. CDK of G₁ phase is a positive and negative complex which determines whether the cell can go into or out of the cell cycle automatically. Oneof the factors is the level of CDK protein and the other is the alteration of CDK inhibitor. P27kipl is just a kind of inhibitive protein. The ex-pression of P27kipl increases in G0 - G₁ phase in common time and de-creases in S phase. P27kipl can...