NK, NKT and Invariant-NKT Cells in Tumor Draining Lymph Nodes of Patients with Breast Cancer

Background: NK (natural killer) and NKT (natural killer T) cells, as components of innate immune system, play a crucial role in tumor progression and dissemination. Objective: To investigate the percentages of NK cells, NKT cells, iNKT (invariant natural killer T) cells, total T lymphocytes as well as activated T lymphocytes, in tumor draining lymph nodes (TDLNs) of patients with breast cancer (BC) and their association with different clinic-pathological features of the patients. Methods: Axillary lymph nodes were obtained from 30 Iranian women with breast cancer. After routine pathological evaluations, mononuclear cells were separated from their lymph nodes and incubated with appropriate fluorochrome conjugated monoclonal antibodies specific for CD3, HLA-DR, CD16/56, and Vα24Jα18-TCR. Data were collected on a four-color flow cytometer and analyzed by CellQuest software. Results: The mean percentages of NK (CD3-CD16/56+), NKT (CD3+CD16/56+) and iNKT (Vα24Jα18-TCR+) cells in TDLNs mononuclear cells of BC patients were 2.04%, 2.44% and 0.1%, respectively. A significant decrease in the percentages of NK and iNKT subsets in patients with grade I was observed compared to grade III (p=0.03 and p=0.01, respectively). Moreover, NK cells were increased in patients with grade III of BC compared to grade II (p= 0.003). Conclusion: The increase in the percentage of NK and iNKT cells in TDLNs of patients with higher grade of BC might suggest a suppressive phenotype for these cells in breast cancer, which merit more functional investigation.