Tumor regression was also observed in vivo in xenograft tumor models (SNU-398 HCC cell-inoculated mice) that were fed an arginine-free diet and treated with a GCN2 inhibitor and senolytic compounds (such as ABT-263, a Bcl-2/Bcl-xl inhibitor) compared to control groups. The gene discussed is BCL2L1; the disease is neoplasm.