Effect of Natural Killer Cells on Human Breast Cancer Cell Line and Its Mechanism
Different from traditional chemotherapy, NK cell adoptive immunotherapy has a lower incidence of severe toxicity, better tolerance, and can improve the quality of life and prolong the survival period of patients. NK cells play an important role in innate and acquired immunity. In this paper, the phenotype of natural killer (NK) cells expanded in vitro was observed, and the killing effect and mechanism of NK cells on different breast cancer cell lines were discussed. The average contents of NK cells, natural killer T cells (NKT cells) and T lymphocytes were (73.5 ± 11.2)%, (18.7 ± 10.6)%, (4.2 ± 0.7)%, respectively. The positive rates of NKG2D, NKp30, NKp44 and dnaX helper molecule 1 (DNAM-1) were (81.3 ± 5.1)%, (82.1 ± 5.4)%, (21.6 ± 2.5)% and (81.3 ± 3.7)%, respectively. The killing rates of NK cells to MDA-MB231 and MCF-7 breast cancer cells were (60.5 ± 1.0)% and (62.5 ± 3.2)% respectively. After amplification, NK cells express some activated molecules, which can kill breast cancer cells. The increased antitumor activity of NK cells may be related to the high expression of these activated molecules.