Expression of ISG15 in colorectal cancer and exploration of its mechanism of action

Interferon Stimulated Gene 15 (ISG15), as the first interferon-stimulated gene identified, has a close relationship with the occurrence and development of many malignant tumors. However, its expression and mechanism of action in colorectal cancer (CRC) are still unclear. In this study, we verified that the expression of ISG15 was significantly elevated in CRC cells and tissues by bioinformatics analysis and experiments, and was associated with poor prognosis of CRC patients. Functional enrichment analysis revealed that ISG15 differentially expressed genes were primarily enriched in the mTOR pathway, the IL-6/JAK/STAT3 pathway, and other cancer-related pathways. In vitro and in vivo experiments confirmed that ISG15 possesses the ability to promote the proliferation, migration, and invasion of colorectal cancer cells. Transcriptome sequencing data indicated that ISG15 differentially expressed genes were primarily enriched in the mTOR signaling pathway, adhesion plaques, and other cancer-related pathways. Protein level analysis confirmed that ISG15 could influence the autophagy level of colorectal cancer cells.