RNA seq analysis of T cells,EpCAM CAR-T cells and rapamycin-pretreated EpCAM CAR-T cells

Purpose: Compared the differences in the transcriptome of T cells versus EpCAM CAR-T cells and EpCAM CAR-T cells versus rapamycin-pretreated EpCAM CAR-T cells.Methods: Next-generation sequencing (NGS) has revolutionized the systems-based analysis of cellular pathways. The goals of this study are to compare NGS-derived transcriptome profiling (RNA-seq) between T cells and EpCAM CAR-T cells,and between EpCAM CAR-T cells and rapamycin-pretreated EpCAM CAR-T cells. Results: RNA-seq showed that CAR-T cells significantly upregulated the expression of exhaustion markers compared to T cells. Gene Set Enrichment Analysis (GSEA) analysis showed that CAR-T cells cells were enriched for signatures of apoptosis. Compared with T cells, Kyoto Encyclopedia of Genes and Genomessignaling(KEGG) pathway analysis showed that the PI3K/AKT/mTOR signaling pathway was significantly enriched. Likewise, GSEA showed that the mTOR signaling pathway was significantly upregulated in CAR-T cells. Next, we analyzed the RNA-seq data between CAR-T cells and rapamycin-pretreated CAR-T cells. RNA-seq showed that rapamycin-treated CAR T down-regulated the expression of exhaustion markers compared with untreated CAR-T cells. GSEA analysis showed that the apoptosis-related gene set was enriched in untreated CAR-T cells.Conclusions:In vitro culture promotes the terminal differentiation of CAR-T cells.CAR-T cells present a highly activated mTOR phenotype. Rapamycin pretreatment prevents CAR-T cells terminal differentiation. Overall design: T cells versus EpCAM CAR-T cells and EpCAM CAR-T cells versus rapamycin-pretreated EpCAM CAR-T cells