Similarly, co-culture of T-ALL samples with MS5 cells in which ERK1 and/or ERK2 were silenced (shERK1/2 MS5 cells) resulted in a significant increase in blast cell proliferation compared to control co-cultures (shCTL MS5; Fig 2C and Supplementary Fig S3). The gene discussed is MAPK1; the disease is acute lymphoblastic leukemia.