Data from Cross-talk between Myeloid and B Cells Shapes the Distinct Microenvironments of Primary and Secondary Liver Cancer

<div>Abstract<p>The tumor microenvironment is distinctive in primary and secondary liver cancer. B cells represent an important component of immune infiltrates. Here, we demonstrated that B cells are an important regulator in hepatocellular carcinoma (HCC) and colorectal cancer liver metastasis (CRLM) microenvironments. B cells displayed distinct developmental trajectories in HCC and CRLM. Single-cell analysis revealed that IgG⁺ plasma cells preferentially accumulated in HCC, whereas IgA⁺ plasma cells were preferentially enriched in CRLM. Mechanistically, IgG⁺ plasma cells in HCC were recruited by tumor-associated macrophages via the CXCR3–CXCL10 axis, whereas IgA⁺ plasma cells in CRLM were recruited by metastatic tumor cells via CCR10–CCL28 signaling. Functionally, IgG⁺ plasma cells preferentially promoted protumorigenic macrophages formation in HCC, and IgA⁺ plasma cells preferentially induced granulocytic myeloid-derived suppressor cells activation in CRLM. Clinically, increased infiltration of IgG⁺ plasma cells and macrophages in HCC was correlated to worse survival, whereas increased intratumoral IgA⁺ plasma cells and neutrophils in CRLM indicated poor prognosis. Taken together, this study demonstrated plasma and myeloid cell-mediated immunosuppression in HCC and CRLM, suggesting that selectively modulating primary or secondary tumor-related immunosuppressive regulatory networks might reprogram the microenvironment and provide an immunotherapeutic strategy for treating liver cancer.</p>Significance:<p>The immunomodulatory patterns of tumor-infiltrating B cells are distinct in primary and secondary liver cancer, with plasma cells mediating important physiologic processes that drive cancer progression.</p></div>