Hes1 directs cell division, in part, by repressing Pten expression in mouse (Wong et al. 2012), in human large cell neuroendocrine carcinoma (Nasgashio et al. 2011), and in regenerating Clara cells of wild-type lungs (Xing et al. 2012). Here, HES1 is linked to large cell neuroendocrine carcinoma.