Radiation could induce DNA damage,cell death,and changes of tumor phenotype and tumor microenvironment leading to the regulation of immune response.Immune checkpoint signaling pathways are involved in the immune tolerance of anti-microorganism responses and thus limit tissue damage.In the anti-tumor immune response,these pathways are associated with anti-functional activation of specific cytotoxic T cells and also enhance the inhibition effect of immune response,which always result in immune escape.Blockade of the immune checkpoint signaling pathways benefits to the anti-tumor inmune responses and could delay tumor progress.As a result,the combination treatment of radiotherapy and immune checkpoint biockade has attracted more attentions in clinical application.This paper reviews the recent research progresses in the radiation effect of immune system,the regulation of immune checkpoints and the combination treatment of radiotherapy and immune checkpoint blockade in tumor therapy,trying to arouse some new clues in cancer therapy.

Autophagy occurs in all types of eukaryotic cells, which has a rigid connection with the normal or abnormal development of cells and is associated with many diseases. There're lots of molecular control elements and multiple signaling pathways involved in regulating autophagy. As a form of type Ⅱ programmed cell death, autophagy participates in maintaining cell homeostasis and pathogenesis of various of diseases through interacting with apoptotic pathway. Recent studies show that autophagy has effects on the occurrence and development of tumor cells through influencing on cell cycle, apoptosis-associated factors and angiogenesis.

Objective: To identify the differentially expressed genes (DEGs) between hepatocellular carcinoma (HCC) tissues and normal liver tissues by bioinformatic methods, and to explore the intrinsic mechanism of these candidate genes involving in the occurrence and development of HCC from transcriptome level as well as the clinical significance of their associations with the prognosis of HCC patients. Methods: Gene expression profiles of GSE45267, GSE64041, GSE84402 and TCGA were downloaded from GEO (Gene Expression Omnibus) and TCGA(The Cancer GenomeAtlas), respectively. R software and Bioconductor packages were used to identify the DEGs between HCC tissues and para-cancer tissues, and then Gene Ontology (GO) Enrichment analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, Protein-Protein Interaction (PPI) network analysis and survival analysis were performed. Results: Forty-six up-regulated genes and 154 down-regulated genes were screened out,and GO enrichment analysis showed that these DEGs were mainly related to cell division, proliferation, cycle regulation, oxidation-reduction process and certain metabolic pathways. KEGG pathway analysis revealed that DEGs were mainly involved in tryptophan metabolism, retinol metabolism and other metabolic pathways as well as p53 pathway. Over-expression of a panel of up-regulated genes (CCNA2, CDK1, DLGAP5, KIF20A, KPNA2 and MELK) was shown to be significantly negatively correlated with the prognosis of HCC patients in the TCGA dataset (all P<0.01). Conclusion: A set of up-regulated hub genes that are negatively correlated with prognosis will provide potential guiding value for the clinical research on the diagnosis and treatment of HCC.