BMI1/NF-κB axis remodeling TAMs phenotype promotes the malignant biological behavior of oral squa-mous cell carcinoma
Objective:To investigate the impact of BMI1 expression in OSCC on the recruitment and differentiation of tumor-associat-ed macrophages(TAMs).Methods:BMI1 expression in 519 cases of OSCC tissues and 44 normal controls was analyzed using online datasets of GEPIA 2.0,and validated in 3 cases of OSCC samples and controls by qRT-PCR and western blotting.The function of BMI1/NF-κB axis during OSCC carcinogenesis was investigated by CCK8 assays,wound healing test and transwell assays.Macrophage phenotypes and recruitment were determined using qRT-PCR and western blotting following coculture of the cells with human monocyte cells(THP-1)by OSCC conditioned medium.Moreover,a cell line-derived xenograft(CDX)model was used to detect the effect of BMI1 on tumor growth in vivo.Results:Compared with the normal tissues and cells,the expression level of BMI1 in OSCC tissues and cells was significantly upregulated.BMI1 knockdown impaired the proliferation,migration,and invasion abilities of OSCC cell lines in NF-κB-dependent manner.Furthermore,OSCC cells with high BMI1 expression inhibited the migration of THP-1 cells,promoted M2-like macrophage polarization through NF-κB pathway in vitro.Xenograft experiments further confirmed the inhibitory effect of BMI1 knockdown on the tumorigenesis ability of OSCC cells in vivo.Conclusion:BMI1 promotes M2-like polarization by regulating NF-κB and may be used as a potential therapeutic target for antitumor immunity.