Analysis of peripheral immune cell typing in breast cancer lung metastasis model of miR-155 knockout mice / 中国免疫学杂志

ABSTRACT

Objective:To establish a mouse model of breast cancer lung metastasis with miR-155 knockout(miR155-/-)mice,and to compare the difference of peripheral blood immune cell typing between miR155-/-mice and C57BL/6J wide-type(WT)mice.Methods:Bioinformatics analysis was used to explore the expression level of miR-155 in breast cancer tissues and peripheral serum,and its relationship with prognosis.Mouse model of lung metastasis of breast cancer was established by tail vein injection;peripheral blood was collected for flow cytometry,and the immune cell typing was analyzed;the lung tissues were collected for immunohisto-chemical detection to observe the tumor metastasis.Results:Percentage of T lymphocytes and monocytes in peripheral blood of miR155-/-mice was significantly decreased compared with WT mice(P<0.05),percentage of myeloid inhibitory cells(MDSCs)was increased significantly(P<0.05),in which the proportion of monocyte subsets(M-MDSC)was significantly decreased(P<0.05),while the proportion of granulocyte subsets(G-MDSC)was significantly increased(P<0.05).In lung metastasis model of breast can-cer,percentage of T lymphocytes in peripheral blood of miR155-/-mice was significantly higher compared with WT mice,while per-centage of NK cells was decreased significantly(P<0.05),percentage of neutrophil was significantly decreased(P<0.001),propor-tion of Th cells in T lymphocytes was significantly decreased(P<0.05),proportion of M-MDSCs was significantly decreased(P<0.01),while proportion of G-MDSCs was significantly increased(P<0.01).Conclusion:Deletion of miR-155 gene leads to significant differences in peripheral immune cell typing,making mice more susceptible to lung metastasis of breast cancer.