5-Octyl-α-ketoglutarate (5-Octyl 2-oxopentanedioate) is a cell-permeable substrate for lysine demethylase. 5-Octyl-α-ketoglutarate is related to protein demethylation, inhibits cell proliferation of wtCRBN expressing cells, and also enhances Lenalidomide (HY-A0003)-induced sensitivity and inhibits myeloma (MM) ) drug resistance of cells. When myeloma (MM) cells undergo glutamine-dependent proliferation, α-ketoglutarate increases glutamine catabolism to promote protein demethylation^[1].