Abstract
Colorectal cancer (CRC), one of the most prevalent and lethal malignancies of digestive system, continues to impose a substantial burden on global health due to its high morbidity and mortality. Tumor microenvironment (TME) is a critical regulator for CRC progression and therapeutic response, but the in-depth understanding on the relationship of TME with CRC remains to be elucidated. In this study, we leveraged single-cell RNA sequencing (scRNA-seq) and bulk RNA-seq data to dissect the immune heterogeneity in CRC patients. The differential expression genes analysis, functional enrichment analysis, random forest analysis and the Least Absolute Shrinkage and Selection Operator method were used to construct a molecular immune prognostic model. The molecular model demonstrated robust performance in stratifying patients based on their immune microenvironment characteristics. The experimental results showed that TIMP1 was highly expressed in CRC. Knockdown of TIMP1 gene significantly inhibited RKO cell proliferation and invasion. By integrating scRNA-seq and bulk RNA-seq data, we developed a new prognostic model that effectively predicts clinical outcomes in patients with CRC and identifies TIMP1 as a promising prognostic biomarker for CRC.