2023, Vol. 27 ›› Issue (11): 1728-1732

Effects of epidermal growth factor receptor on proliferation, differentiation and apoptosis of mouse articular cartilage surface cells

Zhu Zhoujun1, Zhang Jiahui1, Gao Jian1, Xu Bin1, Wang Chao2, Xiang Wei2, Jia Haoruo3, Wang Guosheng1   

Abstract: BACKGROUND: Epidermal growth factor receptor is a key factor regulating the cell cycle and its downstream signaling pathway is widely involved in the regulation of various biological processes of cells.
OBJECTIVE: To isolate and culture articular cartilage surface cells from mice and to verify the effect of epidermal growth factor receptor signaling pathway on the proliferation, differentiation and apoptosis of articular cartilage surface cells.
METHODS: Articular cartilage surface cells from mice were isolated and cultured in vitro by fibronectin adhesion and enzyme digestion and identified. Passage 3 cells were separately treated with transforming growth factor α (100 μg/L), Gefitinib (10 μmol/L), and conventional medium (control group). Cell proliferation was detected by cell counting kit-8 and Ki67 gene expression was detected by RT-PCR. Cell apoptosis was induced by transforming growth factor α (25 μg/L) and AOEB staining was used to identify the apoptosis. RT-PCR was used to detect the expression of Bcl2 and Bax genes. Chondrogenic, osteogenic, and adipogenic induction were conducted for 14-21 days in each group and the mRNA expressions of Sox9, Runx2, and lipoprotein lipase were detected by RT-PCR.
RESULTS AND CONCLUSION: Articular cartilage surface cells isolated and cultured in vitro were long-shaped and positively expressed PRG4 identified by immunofluorescence. Cell counting kit-8 results showed that after treatment with transforming growth factor α, cell proliferation ability and the mRNA level of Ki67 were significantly increased (P < 0.05). AOEB staining results showed that after treatment with transforming growth factor α, the apoptotic level was significantly decreased, the mRNA level of Bcl2 was significantly increased (P < 0.05), and the mRNA level of Bax was significantly decreased (P < 0.05). RT-PCR results revealed that the mRNA level of Runx2 was significantly increased (P < 0.05) and the mRNA level of Sox9 was significantly decreased after treatment with transforming growth factor α. To conclude, the epidermal growth factor receptor signaling pathway is involved in the proliferation, differentiation, and apoptosis of articular surface chondrocytes. Epidermal growth factor receptor mediated by transforming growth factor α can promote the proliferation and osteogenic differentiation of articular cartilage surface cells and inhibit the chondrogenic differentiation and apoptosis of articular cartilage surface cells.
Key words: osteoarthritis, articular cartilage surface cell, epidermal growth factor receptor, Transforming growth factor α, proliferation, differentiation, apoptosis