Mechanism of A549 Cell Apoptosis and Immune Regulating Effect of BRNP on Tumor- bearing Mice

In this study, the immune activity and mechanism of the antitumor activity of Brassica rapa L. polysaccharides were investigated in vitro. BRNP inhibited the growth of human lung adenocarcinoma cell line A549 by changing the cell morphology, reducing the number of cells, promoting apoptosis, and increasing the content of Caspase-3. BRNP enhanced the secretion of immune factors IL-2, IL-6, IL-12, and TNF-α in the serum and spleen of A549 tumor-carrying mice and thus participated in immune regulation. HE staining showed that the pathological state of each dose of BRNP in the turnip group was reduced, and some cells were necrotic compared with the model group. Immunohistochemical results showed that apoptosis was promoted by down-regulating the expression of the Bcl-2 protein and up-regulating the expression of the Bax protein. The assay kit showed that the level of caspase-3 increased in mice, which may be the mechanism of promoting apoptosis.