摘要
ObjectiveTo observe the effect of Banxia Xiexintang containing intestinal absorption solution (BXCIAS) on migration and invasion of polymorphonuclear myeloid-derived suppressor cells (PMN-MDSCs) in gastric cancer microenvironment. MethodThe complex solution (containing 0.63 g·mL-1 crude drug) was prepared. Gastric cancer cells were subjected to non-contact co-culture with PMN-MDSCs in Transwell chamber to create gastric cancer microenvironment. Cell counting kit-8 (CCK-8) assay was used to screen the optimal intervention concentration and time of BXCIAS on PMN-MDSCs for subsequent experiment. The blank group, model group, FAK inhibitor group, and BXCIAS groups (26%, 18%, and 10%) were designed. Scratch assay and Transwell assay were employed to detect the migration and invasion ability of PMN-MDSCs, and enzyme-linked immunosorbent assay (ELISA) to measure the expression of vascular endothelial cell growth factor (VEGF) and matrix metalloproteinase-9 (MMP-9) in tumor microenvironment. The expression levels of PMN-MDSCs pathway-related proteins FAK, phosphorylated (p)-FAK, protein tyrosine kinase (Src), and p-Src were detected by Western blot. ResultThe inhibition rates of PMN-MDSCs by 5%, 50%, 75%, and 100% BXCIAS at 48 h were higher than those at 24 h (P<0.05, P<0.01). The inhibition rate of PMN-MDSCs by 50% BXCIAS at 72 h was lower than that at 48 h (P<0.01), and the inhibition rates by 5% and 100% BXCIAS at 72 h were higher than those at 48 h (P<0.05, P<0.01). There was no significant difference in the inhibition rate by other concentration levels at 48 h. The half-maximal inhibitory concentration (IC50) at 48 h was 18.09%, indicating that 18% BXCIAS and 48 h were the optimal concentration and time, respectively. The migration distance of PMN-MDSCs was large (P<0.01), and the number of migrating and invading cells increased (P<0.01) in the mode group compared with those in the blank group. Compared with model group, FAK inhibitor and BXCIAS at different concentration decreased the migration distance of PMN-MDSCs (P<0.01), and the number of migrating and invading cells (P<0.01), especially the 26% BXCIAS (P<0.01). The expression of PMN-MDSCs pathway-related proteins FAK, p-FAK, Src and p-Src (P<0.01) and the expression of VEGF and MMP-9 (P<0.01) were higher in the model group than in the blank group. Compared with model group, FAK inhibitor and BXCIAS (26%, 18%, 10%) decreased the expression of FAK, p-FAK, and Src (P<0.01), and FAK inhibitor and 18% BXCIAS reduced the expression of p-Src (P<0.01), and the expression of VEGF and MMP-9 (P<0.01). ConclusionBXCIAS can inhibit the migration and invasion of PMN-MDSCs by down-regulating the expression of FAK, p-FAK, Src, and p-Src proteins in the FAK signaling pathway of PMN-MDSCs in gastric cancer microenvironment.
摘要
ObjectiveTo observe the effect of Banxia Xiexintang (BXT)-containing intestinal absorption solution on the apoptosis of polymorphonuclear myeloid-derived suppressor cells (PMN-MDSCs) in gastric cancer microenvironment. MethodBXT-containing intestinal absorption solution was prepared, and gastric cancer cells and PMN-MDSCs were non-contact co-cultured in Transwell chamber to establish gastric cancer microenvironment. Cell counting kit-8 (CCK-8) assay was used to screen the optimal intervention concentration and time of 0-100% BXT-containing intestinal absorption solution prepared by 0.63 g·mL-1 reconstitution solution. Cells were classified into blank group, model group, oxaliplatin group (10 mg·L-1), and BXT (26%, 18%, 10% BXT-containing intestinal absorption solution) group, and the apoptosis of PMN-MDSCs was detected by flow cytometry. The expression of apoptosis-related B-cell lymphoma 2 (Bcl-2), Bcl-2-associated X protein (Bax), and cysteine-aspartic acid protease-3 (Caspase-3) in PMN-MDSCs was detected by Western blot. ResultAfter treatment for 24 h and 48 h, the PMN-MDSCs-inhibiting rate was increased by 5%, 50%, 75%, and 100% BXT-containing intestinal absorption solution compared with that in the blank group (P<0.05, P<0.01). At 72 h, the PMN-MDSCs-inhibiting rate by 50% BXT-containing intestinal absorption solution was lower than that at 48 h (P<0.01), and the PMN-MDSCs-inhibiting rate by 5%, 75%, and 100% BXT-containing intestinal absorption solution showed no significant difference from that at 48 h. Moreover, the half-maximal inhibitory concentration (IC50) at 48 h was 18.40%. Thus, 18% BXT-containing intestinal absorption solution and 48 h were the optimal intervention concentration and time. The survival rate of PMN-MDSCs in model group was higher than that in the blank group (P<0.05), and the apoptosis rate was lower than that in the blank group (P<0.05). Compared with model group, BXT containing intestinal absorption solution lowered the survival rate and raised apoptosis rate of PMN-MDSCs (P<0.05), particularly the 26% BXT-containing intestinal absorption solution (P<0.05). The expression of Bax and Caspase-3 in PMN-MDSCs was lower in the model group than in the blank group (P<0.05), and the expression of Bcl-2 was higher in the model group than in the blank group (P<0.05). The expression of Caspase-3 in PMN-MDSCs increased (P<0.05) and the expression of Bcl-2 decreased (P<0.05) in oxaliplatin group and BXT group compared with those in the model group. The expression of Bax rose in oxaliplatin group and BXT group (10% BXT-containing intestinal absorption solution) (P<0.05). ConclusionBXT can induce the apoptosis of PMN-MDSCs by regulating the expression of apoptosis-related proteins Bax, Caspase-3, and Bcl-2 in gastric cancer microenvironment.