Experimental Study Of The Effect Of TGFBI Knockdown On The Biological Behavior And MAPK/ERK Pathways Of Keloid Fibroblasts

Background and purpose: Keloid is a tumor-like pathological scar whose formation is associated with abnormal proliferation of fibroblasts and excessive deposition of extracellular matrix(ECM).Transforming growth factor beta induced(TGFBI)has been studied as a tumor-promoting gene in various malignancies,such as breast cancer,malignant melanoma,and osteosarcoma.TGFBI promotes tumor cell proliferation,migration,invasion,and metastasis in these diseases.Also,it acts as a connective tissue protein that can cause excessive ECM deposition by promoting cell-ECM interactions.The mitogen-activated protein kinase/extracellular signal-regulated kinase(MAPK/ERK)signaling pathway is a classical pathway in the pathogenesis of keloids.It is mainly responsible for regulating biological behaviors such as cell proliferation,migration,and cell differentiation.However,whether TGFBI can play a role in keloid fibroblasts biological behavior and MAPK/ERK signaling pathway is unclear.Objective: This study aims to find new ways to treat keloids by analyzing the expression of TGFBI in keloid tissues and cells and whether it can influence cell biological behavior and the MAPK/ERK signaling pathway.Methods: Normal skin fibroblasts(NFs)were extracted by harvesting normal skin excised after abdominoplasty and circumcision,and keloid fibroblasts(KFs)were extracted from discarded keloid tissue excised by surgery.Western blotting(WB)and real-time fluorescence quantitative PCR(q PCR)experiments were performed to detect the expression of TGFBI in NFs and KFs.The experimental group was transfected with TGFBI-targeted si RNA to knock down the TGFBI expression level in KFs,while the blanked si RNA-transfected KFs served as the control group.The changes in the proliferation ability of KFs after TGFBI knockdown were observed based on the results of the cck8 assay and clone formation assay;the migration ability of KFs after TGFBI knockdown was determined by scratch assay and transwell assay;the effect of TGFBI on apoptosis of KFs was analyzed using flow cytometry.Finally,the expression levels of collagen and fibrotic proteins,as well as the expression of MAPK pathway-related proteins,were evaluated by WB experiments.Results: 1.The m RNA and protein expression levels of TGFBI were significantly higher in KFs compared to normal fibroblasts;2.Knockdown of TGFBI inhibited the proliferation and migration of KFs and promoted apoptosis;3.Knockdown TGFBI reduces the expression levels of collagen and fibrotic related proteins of KFs;4.Knockdown of TGFBI reduced the expression of MAPK/ERK-related proteins.Conclusion: TGFBI promoted the migration,proliferation,fibrosis and the synthesis of collagen in the extracellular matrix of KFs,and inhibited apoptosis.At the same time,promoted the expression of related proteins of the MAPK/ERK signaling pathway.It can suggest that TGFBI may be a potential therapeutic target for the treatment of keloid disease.