Noncoding RNAs: Regulating the crosstalk between tumor-associated macrophages and gastrointestinal cancer.

Gastrointestinal (GI) cancers, one of the most lethal cancers nowadays, have caused millions of deaths. The tumor microenvironment (TME) is a complex ecosystem containing multiple cells, such as immune cells, cancer cells, and endothelial cells. Tumor-associated macrophages (TAMs), the predominant cells infiltrating the TME, have been verified to play a crucial role in regulating tumor progression. Noncoding RNAs (ncRNAs) are involved in mediating tumor-infiltrating immune cells, including TAMs. GI cancer cells produce various ncRNAs to modulate TAM infiltration and polarization. Meanwhile, ncRNAs play a pivotal role in macrophage and cancer cell metabolic reprogramming. Furthermore, macrophages mediate the impact of ncRNAs on chemoresistance, metastasis, and progression of GI cancer. In this review, we summarize recent research advances in the crosstalk between macrophages and GI cancer regulated by ncRNAs. Moreover, we propose the promising role of ncRNAs as potential targets and prognostic biomarkers in cancer treatment, hoping to facilitate the identification of new targets for immunotherapy.