OSMI-2 is a cell-permeable inhibitor of O-linked N-acetylglucosamine transferase (OGT).

In ?HCT116 cells,OSMI-2 ?treatment reduces O-GlcNAc levels at short treatment times (<8h).?However, O-GlcNAc levels begins to recover at longer treatment times with OSMI-2.?A decrease in HCF-1 cleavage products and the appearance of uncleaved HCF-1 in cells treated with OSMI-2 ?is observed.?Because OGT knockdown is known to decrease cell proliferation, the effects of OSMI-2 on cell growth in culture over 96h is also monitored.?Although there is no evidence of apoptosis, the reduced growth of cells over time is observed, consistent with the knockdown results.?A time course performed with 20 μM OSMI-2 shows reciprocal changes in the abundance of OGT and OGA, with a particularly large increase in OGT;?this may explain the recovery in O-GlcNAc levels with OSMI-2.?At 24h where O-GlcNAc levels fully recovered[1].