GSK503 inhibits the methyltransferase activity of WT and mutant EZH2 with similar potency. In a panel of seven DLBCL cell lines, GSK503 causes growth inhibition and the effects are enhanced by ABT737 or Obatoclax.
In vivo
In C57BL6 mice immunized with SRBC, GSK503 (150 mg/kg, i.p.) reduced the level of H3K27me3 in splenocytes. In male SCID mice bearing SUDHL4 and SUDHL6 tumors, GSK503 (150 mg/kg, i.p.) inhibits tumor growth. In C57Bl/6 mice bearing murine B16-F10 tumors, GSK503 (150 mg/kg, i.p.) significantly reduces global H3K27me3 levels, inhibits tumor growth and virtually abolishes metastases formation.
