p21^WAF1/CIP1在视网膜母细胞瘤中的表达及意义

目的探讨p21^WAF1/CIP1在视网膜母细胞瘤（RB）中的表达及其与肿瘤的病理分期、组织分型、浸润深度的关系。方法利用免疫组织化学法检测p21^WAF1/CIP1在46例RB组织和15例正常视网膜组织中的表达。结果p21^WAF1/CIP1主要表达于细胞核及细胞浆内,在RB中的阳性表达率为47.83%,与正常视网膜组织相比差异有统计学意义（P=0.007）,并随肿瘤病理分期的进展而下降,与组织分型和浸润深度有关（P〈0.05）。结论p21^WAF1/CIP1在RB的发生发展过程中起重要作用,表达的下降与肿瘤恶化及预后不良相关。

Expression of p21WAF1/CIP1 in retinoblastoma and its significance

Objective p21^WAF1/CIP1 is an inhibiting gene of cellular cycle. Researches demonstrated a closely relationship between p21^WAF1/CIP1 expression and many tumors. Present study was to investigate the expression of p21^WAF1/CIP1 in retinoblastoma （RB） and explore the relationship of its expression with clinicopathological parameters. Methods Forty-six RB specimens were obtained during the surgery and divided into I - V stagus of RB according to the criteria of R-E. Fifteen normal retinal tissues were collected from the donator of corneal transplantation. Expression of p21^WAF1/CIP1 in RB and normal retina were examined using immunohistochemistry. The percentage of p21^WAF1/CIP1 positive cells was scored based on Immunochemical Reactive System, and the staining status was scored based on color intensity. The positive result was identified as the product of positive cell score and p21^WAF1/CIP1 color intensity score. The relationship of expression of p21^WAF1/CIP1 with RB stage, histological phenotype and infiltration depth were investigated. The prognosis of immunochemistry was performed by double blindness method. Results The p21^WAF1/CIP1 was positively expressed mainly in cellular nucleus and cytoplasm, p21^WAF1/CIP1 was positively expressed in 47.83% of RB specimens; whereas 86.67% normal retinal tissues expressed p21^WAF1/CIP1, showing a statistically significant difference between them（χ^2 = 6. 980, P = 0. 007 ）. The positive ratio of p21^WAF1/CIP1 was remarkably decreased with the advancement of stagmg（χ^2 = 12. 821 ,P = 0. 017）. The cell number of p21^WAF1/CIP1 expression was significantly increased in differentiated RB specimen compared with undifferentiated RB specimens（χ^2 =4.76,P = 0. 023 ）, and the same tendency was found in optical nerve infiltrated specimens compared with non-optical nerve infiltrated specimens （χ^2 = 4.45, P = 0. 030 ）. Conclusion p21^WAF1/CIP1 plays an important role in genesis and development of RB, and the decrease of its expression has a closely relat