Abstract: Objective To investigate the profile of microRNA expression in tumor associated macrophage (TAM). Methods An xenograft mouse model was established by using mouse breast cancer cell line 4T1. TAM were isolated from the tumor tissue. The microRNA expression profile was detected by using a microRNA chip assay. The result of chip assay was validated by real-time PCR and analyzed by bioinformatics. The peritoneal macrophage was used as control. Results There were significant changes in 59 microRNAs’ expression in TAM compared with the negative control. Among these microRNAs, 23 microRNAs’ expression was up regulated and 36 microRNAs down regulated. These microRNAs participate in the regulation of various signaling pathways. Conclusion Profile of microRNA expression and bioinformatics analysis suggested microRNA plays an important role in regulation of TAM differentiation.

Key words: microRNA, tumor associated macrophage, chip, bioinformatics