CD274 and melanoma: There was no evidence that GNV-RNAs enhanced anti-PD-L1 mediated therapy against B16F10 melanoma, but gut metabolites from GNV-RNAs fed specific-pathogen-free (SPF) hFB mice recovered the activity of GNV-RNAs mediated enhancing of anti-PD-L1 therapy against melanoma growth and lung metastasis (Fig. 6D).