RARA and acute myeloid leukemia: Cell line/primary blasts (12 primary AML patients, U937, THP-1, NB4, and NB4-derived ATRA-resistant cell lines NB4-MR2, NB4-LR1, and NB4-LR2, as well as NB4FLAG-RARα and U937FLAG-RARα cell lines with stable expression of FLAG-RAR-α.