ABSTRACT
Reticulocalbin 1 (RCN1), a calcium-binding protein located in the endoplasmic reticulum (ER) lumen, contains six conserved regions. Its main functions include maintaining intracellular homeostasis and regulating cell proliferation and apoptosis, and it plays an important role in the development of various tumours. However, the exact function of RCN1 in oral squamous cell carcinoma (OSCC) is not fully understood. Therefore, the aim of this study was to investigate the effects of RCN1 on the biological behaviour of OSCC and the regulation of tumour-associated macrophage (TAM) polarization. The expression of RCN1 in OSCC and normal oral mucosa was evaluated through bioinformatics analysis and immunohistochemical staining. The growth, migration, and invasion of OSCC cells were observed after knockdown of RCN1 using CCK-8 and Transwell assays. Apoptosis was detected by flow cytometry. The effect of tumour cell-derived RCN1 on the polarization of THP-1 macrophages was investigated by establishing a coculture model of THP-1 macrophages and OSCC cells. Additionally, changes in the expression levels of relevant proteins were detected using Western blotting. The upregulation of RCN1 in tumour tissues compared to normal oral mucosal tissues is associated with a poor prognosis and can be utilized as a prognostic indicator for OSCC. Knockdown of RCN1 inhibited the proliferation, migration, and invasion of OSCC cells. Additionally, knockdown of RCN1 in Cal-27 and SCC-25 cells resulted in inhibition of the M2 polarization of THP-1 macrophages. RCN1 knockdown inhibits OSCC progression and M2 macrophage polarization. Targeting RCN1 may be a promising approach for OSCC treatment.
Subject(s)
Carcinoma, Squamous Cell , Head and Neck Neoplasms , Mouth Neoplasms , Humans , Carcinoma, Squamous Cell/pathology , Cell Line, Tumor , Cell Movement/genetics , Cell Proliferation/genetics , Gene Expression Regulation, Neoplastic , Head and Neck Neoplasms/pathology , Macrophages/metabolism , Mouth Neoplasms/pathology , Squamous Cell Carcinoma of Head and Neck/pathologyABSTRACT
INTRODUCTION: EP300 is considered to be a cancer suppressor gene that plays a role in tumor development, but some studies have reported that it is not an oral squamous cell carcinoma suppressor gene, because there was neither epigenetic inactivation of the gene nor a mutation resulting in functional impairment. However, there is no relevant study on whether EP300 is the exact carcinogenic effect and its mechanisms of carcinogenic effects in oral squamous cell carcinoma. METHODS: Western blot analysis and quantitative real time polymerase chain reaction experiments verified the protein and mRNA expression of EP300 in oral squamous cell carcinoma; The effects of EP300 knockout on glucose consumption and lactic acid production were detected by glycolysis experiments; The relationship between pathway-related proteins and EP300 was verified by bioinformatics analysis and co-immunoprecipitation experiment. RESULTS: Our experimental results confirm that the protein and mRNA of EP300 are highly expressed in oral squamous cell carcinoma, and after knocking out the EP300, the glycolysis ability, invasion, migration, and other biological functions of oral squamous cell carcinoma, are inhibited at the same time. Pathway-related experiments have confirmed that EP300 plays a role in promoting cancer through the transforming growth factor-beta receptor II (TGF-ßRII)/EP300/Smad4 cascade pathway. CONCLUSION: EP300 plays a carcinogenic role in OSCC showed that the TGF-ßRII/EP300/Smad4 cascade pathway is involved in oral squamous cell carcinoma.
