Bmi1 mediated migration, invasion and proliferation of stem cells of tongue squamous cell carcinoma

doi:10.19438/j.cjoms.2018.02.002

Abstract

Abstract: PURPOSE: To investigate the mechanism of Bmi1 mediating migration, invasion and proliferation of stem cells of tongue squamous cell carcinoma (TSCC). METHODS: SP (side population cell, SP) and non-SP (non-side population cell) cells were sorted by FCM using Hoechst33342 method. Transwell assay was performed to detect migration and invasion of SP cells after Bmi1 knockdown. Sphere forming assay was conducted to detect sphere forming rate of SP cells after Bmi1 knockdown. Colony forming assay was used to detect colony forming rate of SP cells after Bmi1 knockdown. CCK8 assay was used to detect proliferation of SP cells after Bmi1 knockdown. Western blot assay was used to detect expression of invasion and metastasis related genes (SOD2 and Slug) and stem cell markers (ABCG2 and Nanog) in SP cells after Bmi1 knockdown. The data was analyzed using SPSS 17.0 software package. RESULTS: After knockdown of Bmi1 in SP cells, migration and invasion were significantly inhibited compared to control siRNA transfection. SP cells transfected with Bmi1 siRNA displayed significantly decreased sphere formation and colony formation compared to the cells transfected with control siRNA. The proliferation of SP cells was significantly inhibited after transfection with Bmi1 siRNA. The expression of SOD2, Slug and stem cell markers (ABCG2, Nanog) in SP cells were significantly decreased after transfection with Bmi1 siRNA. CONCLUSIONS: Bmi1 knockdown inhibited migration, invasion and proliferation of cancer stem cells in TSCC.

Key words: Tongue squamous cell carcinoma, Cancer stem cell, Bmi1, Migration, Invasion

CLC Number:

R739.8

HE Qian-ting, TANG Lei-le, SUN Jing-jing, LU Zhi-yuan, WANG An-xun. Bmi1 mediated migration, invasion and proliferation of stem cells of tongue squamous cell carcinoma[J]. China Journal of Oral and Maxillofacial Surgery, 2018, 16(2): 102-107.

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