https://tw.voicetube.com/everyday/20171026

英文：

It's frequently the case that new drugs, which work on these lab-grown cells, will fail in clinical trials with real patients. One of the complexities of aggressive tumors is that they can have multiple populations of slightly different cancerous cells.

常有的是，新藥能作用在實驗室培養出的細胞，卻在人體測試階段時失去效用。惡性腫瘤的複雜性在於它能分裂出許多有些微差異的癌細胞群。