Effect of amino acid restriction diet (SARD) combined with anti-PD-L1 on gene expression of cecum orthotopic CT26 tumors.

Since both endogenous synthesis in tumor cells and bacterial sulfur reduction activities are sources of H2S in colon cancer microenvironment, in addition to using CBS -/+ mice, we also investigated the roles of reducing H2S through adopting a sulfur amino acid restriction diet (SARD) (0.15% methionine and 0% cystine) on immunotherapy (anti-PD-L1) of colon cancer. Tumor bulk sequencing was performed in cecum orthotopic CT26 tumors collected from IgG and anti-PD-L1 treated mice both receiving normal diet and SARD. Comparative gene expression profiling analysis of RNA-seq data for 4 groups of cecum orthotopic CT26 tumors (ND + IgG, SARD + IgG, ND + anti-PD-L1, SARD + anti-PD-L1).