associate professor University of Debrecen, Hungary
Disclosure(s):
Peter Hajdu, PhD: No financial relationships to disclose
Introduction/Rationale: The ion channels of T lymphocytes have an important role in effector functions such as activation, cytokine production and tumor cell elimination. T cells recognize and kill cancer cells during continuous monitoring. Although tumor infiltrating lymphocytes (TILs) are able to penetrate the tumor, they cannot fulfil their effector function due to the suppressive nature of the tumor microenvironment. K+ channels, such as Kv1.3 and KCa3.1, stabilize the negative membrane potential of T cells to control Ca2+-influx through CRAC channels and Ca2+-dependent signaling. Here we determined the expression of T cell ion channels from peripheral blood of untreated cancer patients and healthy donors.
Methods: PBMCs were isolated from peripheral blood of breast, lung and prostate cancer patients and healthy donors. Cells were activated with CD3/CD28 antibodies. Whole-cell current was measured in activated CD8+ T cells using patch-clamp technique.
Results: We found that KCa3.1 expression level was lower in breast and female lung cancer patients’ CD8+ cells as compared to gender-matched controls but not in other cancer types. In CD8+ cells from prostate tumor patients the Kv1.3 conductance was significantly higher than in the control group.
Conclusion: In summary, we suppose that down-regulation of KCa3.1 functional expression in female and Kv1.3 level up-regulation male patients in blood CD8+ cells could be a reporter on the presence of malignancy, as we reported before for ovarian and head and neck cancer.
