Evaluation of T cell-mediated antitumor immune response in liver tumors - an approach using tumor and peripheral blood samples

Abstract

Introduction: Hepatocellular carcinoma (HCC) and cholangiocarcinoma (CCA) are primary malignancies of the liver. The identification of highly diverse tumor-infiltrating leukocyte (TIL) subsets, and their distinct functions in the tumor niche, has been an important development in onco-immunology. The aim of this study is to identify potential correlations between tumor type and stage and T cell-mediated antitumor immune responses in patients with these malignancies. Method: Peripheral blood (PB) and tumor samples (TS) were colected from 14 patients with HCC (64±16.8 years) and 5 with CC (62±18.2 years) when performed a surgical resection. Five controls used were (52±3.9 years). PB and TS were processed for the analysis of cytokine production (IL-17 and IFN-γ) by T lymphocytes using flow cytometry. Results: HCC biopsies show a higher percentage of infiltrated immune cells vs. CC (p< 0.05). However, the proportion of TCD8 is higher in CC (p< 0.05). It is interesting to note that in the same patient, tumor-infiltrating TCD4 has a higher percentage of cells producing IFNγ and IL-17, compared to TCD4 from PB (p< 0.05). In PB, the percentage of TCD4 IFNγ+ IL-17+ and TCD8 IL-17+ is decreased in HC and CC vs. control group (p< 0.05). Conclusions: The analysis of the cytokines production profile in HCC and CC allows to understand the important role of immune system in this type of tumors. Moreover, the interaction between immune system components and tumor cells can contribute to the identification of new mechanisms of development and survival of tumors under the immune system action.