We sought to compare chromatin accessibility to transcription factors, histone modifications, binding of CTCF (a component of the cohesin complex that regulates chromatin domain organization), and a POLR2A subunit of RNA polymerase II as indicators of molecular mechanisms that enable gene expression in the liver, where NAGS, CPS1, and citrin are highly expressed; brain, lung and stomach tissues; and cancer cell lines that model glioblastoma, glioblastoma multiforme, lung adenocarcinoma, and stomach adenocarcinoma. The gene discussed is POLR2A; the disease is lung adenocarcinoma.