Integrating Primary and Metastatic scRNA–Seq and Bulk Data to Develop an Immune–Based Prognosis Signature for Colorectal Cancer

Colorectal cancer (CRC) is a highly aggressive cancer, with its treatment and prognosis particularly challenging due to metastasis. The immune response is involved in the whole process of CRC development, and immunotherapy has increasingly become a part of CRC patients’ treatment. However, comprehensive research on the immune microenvironment driving CRC metastasis remains limited. Given this limitation, we proposed a bioinformatics method to construct a metastasis–based immune prognostic model (MIPM) by integrating CRC single–cell RNA sequencing (scRNA–seq) and bulk data. Our study identified several MIPM genes significantly associated with CRC metastasis and progression. MIPM reliably predicted overall survival (OS) and tumor recurrence in CRC across eleven bulk validation datasets. Notably, MIPM could independently predict outcomes beyond traditional clinical factors such as age, sex, and stage. It showed high predictive accuracy in CRC patients treated with chemotherapy. Drug sensitivity and multifaceted immune analyses further underscored the importance of MIPM in therapeutic and immunotherapy response modulation. In conclusion, our findings have profound implications for the illustration of MIPM, which could serve as a new plausible prognostic marker for CRC patients and provide new insights for treatment strategies. The further evaluation and investigation of MIPM will enhance the prognosis and precision therapy of CRC patients.