To investigate liver toxicity and anti-tumor efficacy of anti-4-1BB Abs in preclinical mouse models, we first screened commercially available rat anti-murine 4-1BB Abs across different tumor types (melanoma B16-OVA and colorectal cancer CT-26) and mouse strains (B6 and Balb/c). The gene discussed is TNFRSF9; the disease is melanoma.