Differential Immune Landscape of Hepatocellular Carcinoma Suggests Potential role of Macrophages in Hepatocarcinogenesis

Objectives: To investigate immune cell densities in tumor microenvironment of hepatocellular carcinoma.

Methods: This cross-sectional study was conducted during 2017-2019 at the Dow University of Health Sciences Karachi. A total of 42 subsequent patients undergoing liver biopsy/resection and diagnosed with hepatocellular carcinoma were included in the study. Moreover, a total of 10 control tissues were also included. In order to investigate immune cells densities in hepatocellular carcinoma, immunohistochemistry was performed using antibodies including α-MPO(neutrophils), α-CD-68(macrophages), α-CD-3(T-cells), α-CD-20(B-cells), α-CD-4(CD4+ T-cells) and α-CD-8(CD8+ T-cells). Quantification of immune cells/mm2 was performed as per the College of American Pathologists’ guidelines. Data were analyzed using SPSS version 21. A p-value of 0.05 was considered significant at all times.

Results: We report significantly increased infiltration of macrophages (mean macrophages= 306.57/mm2, p-value<0.05), moderately significant infiltration of neutrophils (p-value=0.06) and B-cells (p-value=0.07) while no significant infiltration of CD4+T-cells (p- value=0.31), and CD8+T-cells (p-value=0.39) in tumour microenvironment of patients with hepatocellular carcinoma.

Conclusion: We provide evidence for increased macrophage infiltration in liver cancer microenvironment suggesting a potential role of these cells in hepatocarcinogenesis.