Itoi T, Yamana K, Bilim V, Takahashi K, Tomita F
Division of Molecular Oncology, Department of Signal Transduction Research, Graduate School of Medical and Dental Sciences, Niigata University, Asahimachi 1-757, Niigata 951-8510, Japan.
Br J Cancer. 2004 Jan 12;90(1):200-5. doi: 10.1038/sj.bjc.6601454.
Previously, we reported that Bcl-2 was frequently expressed in renal cell carcinoma (RCC) specimens, but p53 mutation was a rare event. However, it was unclear whether Bcl-2 positivity was associated with the clinicopathological characteristics and prognosis in RCC. Therefore, we investigated the expression of Bcl-2 protein and its roles in 101 RCC specimens. In addition, the proliferation index (PI), apoptotic index (AI), caspase-3 and p53 expression were examined. The immunohistochemical method was applied for Bcl-2, caspase-3 and p53 protein expression. To investigate the proliferation activity and apoptosis of tumour cells, PI and AI were calculated based on Ki-67 and terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labelling (TUNEL)-positive cells, respectively. Bcl-2 expression was detected in 72 out of 101 (71.3%) specimens. Bcl-2 positivity was inversely correlated with PI (P<0.0001) and AI (P=0.0074). Furthermore, Bcl-2 positivity was significantly correlated with better survival (P=0.0014), and was associated with lower stage (P=0.0301) and grade (P=0.0020). In RCC, frequent Bcl-2 expression was correlated with favourable character without higher PI and AI. Thus, Bcl-2 expression might be applied as a novel predictor of better prognosis in RCC patients.
此前，我们报道过Bcl-2在肾细胞癌（RCC）标本中经常表达，但p53突变却是罕见事件。然而，尚不清楚Bcl-2阳性是否与RCC的临床病理特征及预后相关。因此，我们研究了101例RCC标本中Bcl-2蛋白的表达及其作用。此外，还检测了增殖指数（PI）、凋亡指数（AI）、半胱天冬酶-3和p53的表达。采用免疫组化方法检测Bcl-2、半胱天冬酶-3和p53蛋白的表达。为了研究肿瘤细胞的增殖活性和凋亡情况，分别基于Ki-67和末端脱氧核苷酸转移酶介导的dUTP-生物素缺口末端标记法（TUNEL）阳性细胞计算PI和AI。在101例标本中有72例（71.3%）检测到Bcl-2表达。Bcl-2阳性与PI（P<0.0001）和AI（P=0.0074）呈负相关。此外，Bcl-2阳性与更好的生存率显著相关（P=0.0014），并与较低分期（P=0.0301）和分级（P=0.0020）相关。在RCC中，频繁的Bcl-2表达与良好特征相关，且PI和AI不高。因此，Bcl-2表达可能作为RCC患者预后较好的一种新的预测指标。
