Han Bo, Mehra Rohit, Dhanasekaran Saravana M, Yu Jindan, Menon Anjana, Lonigro Robert J, Wang Xiaosong, Gong Yusong, Wang Lei, Shankar Sunita, Laxman Bharathi, Shah Rajal B, Varambally Sooryanarayana, Palanisamy Nallasivam, Tomlins Scott A, Kumar-Sinha Chandan, Chinnaiyan Arul M
Michigan Center for Translational Pathology, University of Michigan Medical School, Ann Arbor, Michigan 48109, USA.
Cancer Res. 2008 Sep 15;68(18):7629-37. doi: 10.1158/0008-5472.CAN-08-2014.
Recurrent gene fusions involving E26 transformation-specific (ETS) transcription factors ERG, ETV1, ETV4, or ETV5 have been identified in 40% to 70% of prostate cancers. Here, we used a comprehensive fluorescence in situ hybridization (FISH) split probe strategy interrogating all 27 ETS family members and their five known 5' fusion partners in a cohort of 110 clinically localized prostate cancer patients. Gene rearrangements were only identified in ETS genes that were previously implicated in prostate cancer gene fusions including ERG, ETV1, and ETV4 (43%, 5%, and 5%, respectively), suggesting that a substantial fraction of prostate cancers (estimated at 30-60%) cannot be attributed to an ETS gene fusion. Among the known 5' gene fusion partners, TMPRSS2 was rearranged in 47% of cases followed by SLC45A3, HNRPA2B1, and C15ORF21 in 2%, 1%, and 1% of cases, respectively. Based on this comprehensive FISH screen, we have made four noteworthy observations. First, by screening the entire ETS transcription factor family for rearrangements, we found that a large fraction of prostate cancers (44%) cannot be ascribed to an ETS gene fusion, an observation which will stimulate research into identifying recurrent non-ETS aberrations in prostate cancers. Second, we identified SLC45A3 as a novel 5' fusion partner of ERG; previously, TMPRSS2 was the only described 5' partner of ERG. Third, we identified two prostate-specific, androgen-induced genes, FLJ35294 and CANT1, as 5' partners to ETV1 and ETV4. Fourth, we identified a ubiquitously expressed, androgen-insensitive gene, DDX5, fused in frame with ETV4, leading to the expression of a DDX5-ETV4 fusion protein.
在40%至70%的前列腺癌中已发现涉及E26转化特异性(ETS)转录因子ERG、ETV1、ETV4或ETV5的复发性基因融合。在此,我们采用了一种全面的荧光原位杂交(FISH)分裂探针策略,在110例临床局限性前列腺癌患者队列中检测了所有27个ETS家族成员及其5个已知的5'融合伴侣。基因重排仅在先前与前列腺癌基因融合有关的ETS基因中被发现,包括ERG、ETV1和ETV4(分别为43%、5%和5%),这表明相当一部分前列腺癌(估计为30%-60%)不能归因于ETS基因融合。在已知的5'基因融合伴侣中,TMPRSS2在47%的病例中发生重排,其次是SLC45A3、HNRPA2B1和C15ORF21,分别在2%、1%和1%的病例中发生重排。基于这一全面的FISH筛查,我们有四点值得注意的观察结果。第一,通过筛查整个ETS转录因子家族的重排情况,我们发现很大一部分前列腺癌(44%)不能归因于ETS基因融合,这一观察结果将推动对前列腺癌中复发性非ETS异常的鉴定研究。第二,我们鉴定出SLC45A3是ERG的一个新的5'融合伴侣;此前,TMPRSS2是ERG唯一被描述的5'伴侣。第三,我们鉴定出两个前列腺特异性、雄激素诱导基因FLJ35294和CANT1,分别作为ETV1和ETV4的5'伴侣。第四,我们鉴定出一个普遍表达、雄激素不敏感基因DDX5与ETV4框内融合,导致DDX5-ETV4融合蛋白的表达。