Anthropogenic selection enhances cancer evolution in Tasmanian devil tumours

The Tasmanian Devil Facial Tumour Disease (DFTD) provides a unique opportunity to elucidate the long-term effects of natural and anthropogenic selection on cancer evolution. Since first observed in 1996, this transmissible cancer has caused local population declines by >90%. So far, four chromosomal DFTD variants (strains) have been described and karyotypic analyses of 253 tumours showed higher levels of tetraploidy in the oldest strain. We propose that increased ploidy in the oldest strain may have evolved in response to effects of genomic decay observed in asexually reproducing organisms. In this study, we focus on the evolutionary response of DFTD to a disease suppression trial. Tumours collected from devils subjected to the removal programme showed accelerated temporal evolution of tetraploidy compared with tumours from other populations where no increase in tetraploid tumours were observed. As ploidy significantly reduces tumour growth rate, we suggest that the disease suppressi...塔斯马尼亚恶魔面部肿瘤病（Tasmanian Devil Facial Tumour Disease，DFTD）为阐明自然与人为选择对癌症演化的长期影响提供了独特契机。自1996年首次被发现以来，这种传染性癌症已导致其局部种群数量下降超过90%。迄今已报道4种染色体型DFTD毒株，对253份肿瘤样本开展的核型分析显示，历史最悠久的毒株呈现出更高水平的四倍体化。我们推测，该古老毒株的倍性升高，或许是为了适应无性繁殖生物中观测到的基因组衰退效应而演化形成。本研究聚焦DFTD对疾病抑制试验的演化响应。相较于未观测到四倍体肿瘤占比上升的其他种群的肿瘤样本，接受移除项目的袋獾所采集的肿瘤样本，其四倍体化的时序演化进程显著加快。鉴于倍性可显著降低肿瘤生长速率，我们认为该疾病抑制...