SOX9 and non-small cell lung carcinoma: To test whether direct binding of N1ICD to these RBP-Jκ binding sites in the human Sox9 promoter is necessary for induction of Sox9 expression in human NSCLC, we used a luciferase reporter under the control of a 1 kb-fragment of the Sox9 promoter, transiently expressed in the Sox9-low H1838 cells.