Expression And Clinical Significance Of MCM2 In Bladder Carcinoma

Background and Objective: As the most common malignancies of urinary system and male reproductive system in the country, Bladder cancer, with an increasing trend, is in the second place after prostate cancer in western countries. With many features, such as multicenter, easy relapse, a malignant progress trend traits, its incidence includes many factors and many steps of complex changes processes. At the present day, there is still wanting in effective preventive measures, and the treatment is primarily surgical, adding to bladder infusion Chemotherapy, but after the treatment of recurrent, patients usually exist tumor progression for easily relapse. Therefore, looking for accurate response bladder biological behaviour of tumor marker, the early detection, early diagnosis and early treatment becomes especially important. Foreign studies show, MCM2 (Minichromosome maintenance proteins 2) is a member of the family MCMs (Minichromosome maintenance proteins) which plays an important role in DNA duplicating, and existing nothing more than the cell cycle of the nucleus. MCM2, as a more ideal cell proliferation markers expresses only in proliferation cells, for this kind of feature which follows after the cell cycle changes, further more it can reflect cell's propagation liveness accurately. It can better discern normal tissue, atypical hyperplasia and tumor tissue is likely to become malignant tumor and atypical early screening of an important biological markers. This experiment Purpose that bladder carcinomas, cystitis glandularis and normal bladder tissues were detected for the expression of MCM2 by using immunohistochemistry (S-P method), then discuss its relationship between expression and pathologically classification, differentiation degree and the clinical stages and prognosis relation of bladder cancer, and expected to providing theory basis for bladder cancer early diagnosis and prognosis assessment.Materials and Methods: Forty-five cases of bladder carcinoma were collected affiliated hospital of Guilin medical Universty from 2006 to 2009. bladder carcinoma cases included twenty-nine male and sixteen female with age ranging from 45 to 76 years(mean 56 years) and divided into group G₁(14 cases), group G₂(20 cases), group G₃(11 cases), and group T₁(12 cases), group T₂(17 cases), group T₃(10 cases), group T₄(6 cases) according to WHO grading criteria and TNM staging criteria. Another, randomly extract were confirmed by pathological diagnosis twenty cases of Cystitis Glandularis and ten cases of normal bladder tissue as an experimental comparison. Forty-five cases of bladder carcinomas, twenty cases of cystitis glandularis and ten cases of normal bladder tissues were detected for the expression of MCM2 by using immunohistochemistry (S-P method) , then analyzed with clinical and pathological data.Result: By immunohistochemical staining, the expression of MCM2 in normal bladder tissues were negative, in bladder carcinom(a100%) were higher than that in cystitis glandularis(20%). The differences among normal bladder tissues, cystitis glandularis and bladder cancer were statistical significance (P<0.01). In bladder carcinoma, cells diffuse to the epithelial cell layer, the expression becoming stronger with the decrease of pathological differentiation and the disappearance of cell polar, but in cystitis glandularis, Its expression mainly in the Brunn's nest of cell proliferation area. There were statistical significances between the expression of MCM2 with the pathological grade and recurrence of bladder cancer(P<0.05). But it's uncorrelated with the clinical stage.Conclusions: The negative expression of MCM2 in normal bladder tissues may show that cells already in mature differentiation or exit the stage of proliferation. The higher expression of MCM2 in bladder cancer have relative with abnormal cell proliferation or the degree of differentiation, it's a valuable indicator to reflect the biological behavior of bladder cancer, could help the diagnosis for malignant process and prognosis. As a proliferation markers, MCM2 can distinguish the normal bladder tissues, cystitis glandularis and bladder cancer, expected to provide evaluation basis for bladder cancer and precancerous lesions of early screening and treatment.