| Objective:The study was designed to research the effect of tumor-associated macrophages (TAMs) treated by leptin in the progression of breast cancer invasion and metastasis, and to explore the possible molecular mechanism. From the study,we could provide ideas for the clinical treatment of breast cancer.Methods:1 Research has shown that TAMs was mainly contained by M2 macrophages. We first use PMA stimulated human monocytes THP1 differentiated to adherent, followed by the addition of interleukin 4 (IL-4) in the induction system stimulating cells differentiated into TAMs.2 After leptin and other factors treated TAMs, the conditioned medium was collected. We mainly test the invasion and metastasis oftumor cells by the indirect co-culture of TAMs and breast cancer cells.3 qRT-PCR and Western Blotting detect the changes of IL-18 mRNA and protein in TAMs, and analysis the mechanism of signaling pathway.IL-18 secretion levels was determined by ELISA in several cells.4 IHC to analyse the molecule CD 163 of TAMs and IL-18 indifferent progress breast cancer samples. Build nude mouse tumor model of breast cancer, inject CC1. intratumoral, to analyse the tumor growth,liver and lung metastases. Test the different expression of IL-18 treated by leptin.Results:1 The suspension of mononuclear cells induced to differentiate into adherent THP1 of M2 macrophages successfully. Identification of cell phenotype has been done by our lab.2 Through the indirect co-culture experiments of TAMs and breast cancer cells, leptin affects TAMs promote the invasion and metastasis of tumor cells, and this effect may be related with expression and secretion IL-18 in TAMs (P<0.05).3 qRT- PCR and Western Blotting showed IL-18 mRNA and protein levels were elevated in breast cancer cells and TAMs after leptin treatment (P<0.01), ELISA showed IL-18 secretion level increased of various kinds of cells (P<0.01). The IL-18 express and secrete added mainly through cell signaling pathway NF-κB in turn affect IL-18 transcription factor NF-κB1 achieved in TAMs (P<0.01); while through the mechanism of cell signal pathway PI3K/Akt acts on the transcription factor ATF-2 related in MCF-7 cells (P<0.01).4 The patient sample analysis results showed that the malignant progression related to M2 macrophages molecular markers CD 163, and IL-18 is closely related to the progression of breast cancer (P<0.05); nude mice experiments showed that after deleption of macrophages,IL-18 expression was significant low than the group of leptin treated(P<0.05). Macrophage depletion can slow down the tumor growth, reducing the incidence of lung metastases in nude.Conclusion:1 leptin promote the expression of IL-18 in TAMs and breast cancer cells.,then promote the progression of breast cancer invasion and metastasis.2 Leptin activation of NF-κB signaling pathway, regulation of transcription factor NK-κB1 of IL-18 in TAMs; in MCF-7 breast cancer cells by activating PI3K/Akt signaling pathways mainly and act on transcription factor ATF-2 cause. The results show that both the breast cancer cells and tumor-associated macrophages can produce IL-18 protein expression, but the mechanisms may be different.3 From the results of pathological tissue sections, leptin, CD 163 and IL-18 expression in metastatic breast cancer was significantly higher than mammary hyperplasia and non-metastatic breast cancer. Nude breast tumor progression findings indicate that Leptin promote breast tumor growth and metastasis in mice; After application of CCL. to deleption of macrophages, the expression of IL-18 was decreased, tumor growth and transfer were slow down. |
PDF Full Text Request