PDCD1 and hepatocellular carcinoma: The transcriptomics data and metabolomics data of the ZS-SEQ-HCC cohort as well as the transcriptomics data of the ZS-PD1-HCC cohort have been uploaded to the National Center for Biotechnology Information Gene Expression Omnibus (https://www.ncbi.nlm.nih.gov/geo/), with an accession number of GSE195952.