2'-O,4'-C-methylene bridged nucleic acid (2',4'-BNA) is a nucleic acid analogue that has high affinity binding to its complementary RNA. Peroxisome proliferator-activated receptor (PPAR) y belongs to the nuclear hormone receptor superfamily and is a drug target in the treatment of type 2 diabetes. Here, we show the antisense effects of 2',4'-BNA oligonucleotides against PPARy in the human monocytic leukaemia cell line THP-1 and the human colorectal tumor cell line HCT116.