Amine Mechanism Of Tumor Associated Macrophages Interact With Cells Lymphoma And Lenalidomide

BackgroundTumor-associated Macrophage (TAM) is a very important part of the tumor microenvironment. These cells show a remarkable degree of phenotypic and functional plasticity during tumor development. Macrophages play an important role in both tumor initiation and various key steps in growth and metastasis. Several studies have demonstrated that macrophage infiltration is correlated with poor prognosis in patients with different kinds of lymphoma. Targeting TAMs may represent a novel therapeutic strategy against cancer.Objectives1. To explore the effects of lymphoma cells on the differentiation of monocytes from peripheral blood and the effects of TAMs on proliferation of lymphoma cells in vitro. Then investigate the difference between the newly diagnosed lymphoma patients and healthy volunteers.2. To investigate the impact of anti-cancer drug Lenalidomide on the differentiation of monocytes to TAMs and its function in the tumor microenvironment.Methods1. Blood samples were obtained from19newly diagnosed lymphoma patients and8healthy volunteers. Monocytes from peripheral blood were directly co-cultured with lymphoma cell HUT-78by using Transwell apparatus in vitro. Expression of the markers of TAM(CD68and CD163) were tested by Flow Cytometry to analyse the proportion of differentiated TAMs. By making growth curve of HUT-78cells, testing IL-10and VEGF level in the co-culture system and detecting STAT3activation state of HUT-78cells, the function of TAM was also evaluated. Newly diagnosed lymphoma patients were compared with healthy volunteers.2. The peripheral blood mononuclear cells (PBMCs) of the patients and healthy controls were also co-cultured with lymphoma cell HUT-78, using the same methods as above to explore the impact of anti-cancer drug Lenalidomide on the differentiation of monocytes to TAMs and its function in the tumor microenvironment.Results1.The proportion of CD68(+),CD163(+) and CD68&CD163(+) cells were significantly up-regulated after co-cultured with HUT-78lymphoma cells in both patients and healthy controls. There was no statistical significance on the increasing degree between patients and health controls.2. TAMs differentiated from peripheral blood monocytes showed no significant promotion or inhibition of the growth of co-cultured lymphoma cells.3. For patients, the IL-10and VEGF level were significantly lower in the co-culture group than the addition of the two single culture groups (P<0.01). For healthy controls, there was no significant difference between these two.4. For patients, expression of the STAT3was generally lower in the co-culture group than in the lymphoma cell single culture group, however there was no statistical significance. Expression of the STAT3was significantly lower in patients than in healthy controls (P<0.05)5. For patients, treatment with Lenalidomide in the PBMC and HUT-78co-culture system significantly decreased the proportion of CD68(+), CD163(+) and CD68&CD163(+) cells (P<0.01), the proportion of CD68&CD163(+) in CD68(+) which represents the proportion of M2macrophage was also significantly decreased (P<0.01). For control group, the proportion of CD68(+),CD163(+) and CD68&CD163(+) cells were significantly decreased (P<0.01), but the proportion of CD68&CD163(+)in CD68(+) showed no significant decrease (p=0.114)6. For patients, treatment with Lenalidomide significantly decreased the IL-10and VEGF level in the co-culture system (IL-10P=0.003, VEGF P=0.018), TGF-β1was also generally decreased with no statistical significance. For control group, IL-10level was significantly decreased after treatment with Lenalidomide, but the degree was lower in healthy controls than in patients, VEGF and TGF-β llevel showed no significant decrease in the control group.7. For patients, expression of STAT3in the co-cultured HUT-78lymphoma cell was generally down-regulated, but there was no statistical significance. For healthy control, treatment with Lenalidomide showed no effect on the expression of STAT3.Conclusions1. Lymphoma cells can promote the differentiation of monocytes to macrophages with M2-like phenotype. There was no difference on the promoting degree between patients and health controls.2. The TAMs differentiated from patients’monocytes which significantly down-regulated levels of IL-10and VEGF of the co-culture system and the expression of STAT3of co-cultured HUT-78lymphoma cells, exhibited functions more like M1macrophages. In contrast, TAM differentiated from monocytes of healthy controls showed no such effects on the co-culture system.3. For patients, Lenalidomide significantly inhibited the differentiation of monocytes to macrophages with M2-like phenotype in the co-culture system. For healthy controls, Lenalidomide could only inhibit the differentiation of monocytes, but had no significant effects on the proportion of M2macrophages.4. For patients, Lenalidomide could down-regulate levels of IL-10, VEGF and TGF-β1of the co-culture system and the expression of STAT3of co-cultured HUT-78cells to varying degrees. However, Lenalidomide showed no such effects or much weaker effects in the control group.