B lymphocytes: The unknown soldier in the HCC microenvironment

In the concept of immunogenic cancer such as hepatocellular carcinoma (HCC), analysis and studying tumor-infiltrating lymphocytes (TILs) seems to be informative to predict cancer clinical outcomes. Most of TILs contemporary studies aim at T cells as they’re responsible for targeting and killing tumor cells, but T cells cannot work alone. The role of B cells, the other part of lymphocytes, is often ignored. B cells are identified with different densities and within different locations in different stages of HCC. In addition, the functional interaction between infiltrated B cells and T cells in HCC is documented correlating their densities with higher patient survival. B cells constitute the main part of the tertiary lymphocytic structures which their role to guide the clinical decision is arising.

Studying tumor-infiltrating B cells has not been a focal area in TIL research as the prognostic benefits of related publications are less convincing about the clear role of B cells. Depending on the immune contexture, B cells infiltrate into tumor tissue differentiating to different subpopulations to create an immunosuppressive or supportive environment.

In our study, we are tracking B cells in different regions of HCC by immunohistochemical detection of CD20, a marker of naïve and memory B cells. In addition, we investigate functional interactions of B cells with T cells correlating with the pathological condition of the patient. This study could elucidate the role of B cells in HCC and open the door for more specific studies on B cells subsets reinvigorating the immune picture of liver cancer.