Kobayashi et al generated cell lines in vitro from primary xenografted CRC tumour samples and found that LGR5+-sorted cells more efficiently formed colonies in Matrigel and tumours in vivo, compared with LGR5− cells.70 However, following exposure to drugs such as irinotecan, 5FU, or oxaliplatin, LGR5+ cells converted to drug-resistant LGR5− cells with reduced proliferative capacity. The gene discussed is LGR5; the disease is neoplasm.