Integrated Single Cell Analysis Reveals An Atlas of Tumor Associated Macrophages in Hepatocellular Carcinoma.

Hepatocellular carcinoma (HCC), one of the most prevalent cancers globally, is closely associated with tumor-associated macrophages (TAMs), including monocyte-derived macrophages and liver-resident Kupffer cells. Understanding TAM heterogeneity at the cellular level is crucial for developing effective HCC prevention and treatment strategies. In this study, we conducted an integrated single-cell analysis of four cohorts (GSE140228, GSE125449, GSE149614 and GSE156625) to elucidate the TAM landscape in HCC. We identified 284 gene markers, termed Panmyeloid markers, that characterize myeloid cells within this context. Our analysis distinguished six clusters of monocyte-derived macrophages (Macro1-Macro6) and four clusters of Kupffer cells (Kupffer1-Kupffer4). Notably, CXCL10 + macrophages and MT1G + Kupffer cells, predominantly located within tumor tissues, exhibited distinct functional characteristics relevant to HCC. We also explored cellular communication between TAMs and T cells, uncovering potential signaling pathways such as the CXCL10/CXCL11-CXCR3 and CXCL12-CXCR4 networks. These findings enhance our understanding of TAMs in HCC and open new avenues for targeted therapeutic interventions.