Gene expression profiling of Dox-activable K-ras mutation in human primary bronchial epithelial cell line

We constructed a primary lung cell model to permit regulated expression of KRASG12D. To do this, we leveraged a non-transformed, immortalized, human primary bronchial epithelial cell line (HBEC; hTert, CDK4, TP53 knockdown) that remains anchorage dependent and do not develop tumors when implanted into mice. We next modified these cells by stably integrating a regulatable KRASG12D allele, iKRASG12D, such that physiological expression of mutant KRAS is activated upon addition of doxycycline. The HBEC-iKRAS (WT) cell line and HBEC-iKRASG12D (MUT) cell line were propagated with or without Doxycycline (500ng/ml) respectively. RNA profiling of HBEC-iKRASG12D and HBEC-iKRASWT cells revealed widespread changes for HBECs harboring the activated KRAS allele in the presence of Dox. Within the KRASG12D-induced genes, the Molecular Signatures Database identified the oncogenic RAS signature as a top-enriched gene set. Upregulation of Ras signaling in Dox-treated HBEC-iKRASG12D cells was also supported by a significant overlap with a KRAS signature previously characterized by Singh et al. Gene expression microarray analyses were performed on Dox vs. no Dox in HBEC-iKRAS (WT) cell line and HBEC-iKRASG12D (MUT) cell line. multiple group comparisons