中文摘要：

目的：寻找人肾透明细胞癌（clear cell renal cell carcinoma,ccRCC）中CD99转移相关选择性剪接异构体,探讨CD99选择性剪接异构体表达与ccRCC转移的关系。方法：通过选择性剪接数据库（alternative splicing database,ASD）对CD99基因可能存在的选择性剪接异构体进行预测。运用自行设计的5对特异性引物,采用RT-PCR技术,在转移组织、发生及未发生转移的癌组织、癌旁组织的各混合样本中检测6种预测异构体的表达,再对电泳所获条带进行克隆、测序。在各个组织样本中检测CD99Ⅰ、CD99Ⅱ和新型CD99选择性剪接异构体（CD99-Ⅲ）的表达。结果：从6种预测异构体中筛选出一种新型异构体（CD99-Ⅲ）。该异构体在转移组织中表达率（8/9）高于未发生转移的原发癌组织（10/21,P〈0.05）。CD99Ⅰ型在样本中均表达,CD99Ⅱ型在发生转移的原位癌组织中表达率（6/9）远高于未转移的原发癌组织（3/21,P=0.008）。结论：CD99-Ⅲ为一种新型选择性剪接异构体,且CD99Ⅱ型、CD99-Ⅲ的表达可能与ccRCC的转移进展有关。

英文摘要：

Objective：To identify the metastasis associated splice variants of CD99 and investigate the mRNA expression of the splice variants in clear cell renal cell carcinoma（ccRCC） tissues, so as to investigate its relationship with the initiation and progression of ceRCC. Methods： Alternative Splicing Database was used to predict the splice variants of CD99. The six predicted splice variants of CD99 were identified in the metastatic tissues, primary ccRCCs and normal tissues adjacent to cancer by using self-designed primer sets,and were cloned into vectors and sequenced. The mRNA expression of CD99 type Ⅰ ,CD99 type Ⅱ , and CD99-Ⅲ were detected in 9 metastatic tissues and their corresponding cancer tissues, 21 primary ccRCCs and normal tissues adjacent to cancer by RT-PCR. Results： A new isoform of CD99 （CD99-Ⅲ） was identified, which was detected in 8 of the 9 metastatic tissues, a ratio significantly higher than that in the primary ccRCCs without metastasis （10 out of 21 ,P〈0.05）. The results revealed that the transcripts of CD99 type I was present in all of the ccRCC specimens tested; CD99 type Ⅱ was detected in 6 of 9 metastatic corresponding primary cancer tissues,a ratio significantly higher than that in cancer tissues without metastasis（3 out of 21,P=0. 008） . Conclusion： CD99 type Ⅱ and CD99-Ⅲ, a novel splice variant of CD99, may be associated with the initiation and progression of ccRCC.