Ectopic ERK expression induces phenotypic conversion of C10 cells and alters DNA methyltransferase expression.

BACKGROUND

Many lung carcinogens activate mitogen activated protein kinase (MAPK) pathways and DNA methyltransferases (DNMTs) are under investigation as therapeutic targets for lung cancer. Our goal is to determine whether C10 type II alveolar epithelial cells are a sensitive model to investigate ERK-dependent transformation and DNMT expression patterns in experimental lung cancer.

FINDINGS: Ectopic expression of an extracellular signal regulated kinase (ERK)-green fluorescent protein (ERK1-GFP) induces acquisition of growth in soft agar that is selectively associated with latent effects on the expression of DNA methyl transferases (DNMT1 and 3b), xeroderma pigmentosum complementation group A (XPA), DNA-dependent protein kinase catalytic subunit (DNA-PKcs), increased phosphatase activity and enhanced sensitivity to 5-azacytidine (5-azaC)-mediated toxicity, relative to controls.

CONCLUSIONS

Ectopic expression of ERK alone is sufficient to promote phenotypic conversion of C10 cells associated with altered DNMT expression patterns and sensitivity to DNMT inhibitor. This model may have applications for predicting sensitivity to DNMT inhibitors.