The regulatory T cell attracting chemokines CCL1, CCL22 and CCL27 are expressed in hepatocellular carcinoma and peritumoral liver tissue

Introduction:

Hepatocellular carcinoma (HCC) is a tumor strongly influenced by the immune system. Regulatory T cells (Treg) have been shown to have a negative impact on disease progression and survival.

Aim:

We aimed at analyzing expression of Treg attracting chemokines in HCC tissues.

Method:

We determined expression of the chemokines CCL1, CCL22 and CCL27 as well as the infiltration with FoxP3+ Treg and CD8+ T cells in paraffin-embedded tissue sections of 62 HCC patients.

Result:

Indeed, expression of all Treg attracting chemokines was detected in the majority of HCC tissues. Chemokine expression was generally higher in tumor stroma and peritumoral liver tissue than within the tumor. CD8+ T cells and FoxP3+ Treg were found at high levels in many tumor tissues and intratumoral infiltration by Treg positively correlated with CCL22 levels in peritumoral liver. However, no correlation of Treg numbers and expression of CCL1 and CCL27 was detected.

Conclusion:

The chemokines CCL1, CCL22 and CCL27 are expressed in HCC tissues and the peritumoral stroma and may contribute to Treg recruitment and immunosuppression. It will be interesting to investigate the capacitiy of these chemokines as drug targets for cancer therapy.