Thus, the significant positive correlation between high DEC1 expression and high tumour grade that we describe, an association that has been reported in lung cancers (Giatromanolaki et al, 2003) is in accordance with its induction by HIF (Bos et al, 2001) and Stra13's ability to repress differentiation in embryogenesis and adipocytes (Boudjelal et al, 1997; Yun et al, 2002). Here, BHLHE40 is linked to lung carcinoma.