HMGA1 Aggravates Oxidative Stress Injury and Inflammatory Responses in IL-1β-Induced Primary Chondrocytes through the JMJD3/ZEB1 Axis

INTRODUCTION

Osteoarthritis (OA) is associated with oxidative stress injury (OSI) and inflammatory responses in chondrocytes. This study sought to explore the mechanism of high mobility group A1 (HMGA1) in interleukin-1beta (IL-1β)-induced OSI and inflammatory responses in primary chondrocytes.

METHODS

Primary chondrocytes were cultured and treated with IL-1β to establish an OA-cell model. Levels of HMGA1, Jumonji domain-containing 3 (JMJD3), and ZEB1 in cells were determined by real-time quantitative polymerase chain reaction and Western blot analysis. Cell viability, contents of tumor necrosis factor-α, IL-6, and IL-10, reactive oxygen species level, and glutathione peroxidase activity were assessed by the cell counting kit-8 assay, enzyme-linked immunosorbent assay, and assay kits. Enrichment levels of HMGA1 on the JMJD3 promoter and enrichment levels of JMJD3 and trimethylated histone H3 at lysine 27 (H3K27me3) on the ZEB1 promoter region were determined by chromatin immunoprecipitation. Functional rescue experiments were performed to analyze the impact of ZEB1 and JMJD3 on IL-1β-induced chondrocytes.

RESULTS

IL-1β treatment induced HMGA1 upregulation, OSI, and inflammatory responses in chondrocytes. HMGA1 downregulation reduced IL-1β-induced OSI and inflammatory responses in chondrocytes. Mechanically, HMGA1 was bound to the JMJD3 promoter to promote JMJD3 transcription, and JMJD3 induced demethylation of H3K27me3 on the ZEB1 promoter to promote ZEB1 transcription. Overexpression of JMJD3 or ZEB1 neutralized the protective role of silencing HMGA1 in IL-1β-induced chondrocytes.

CONCLUSION

HMGA1 aggravated IL-1β-induced OSI and inflammatory responses in chondrocytes through the promotion of JMJD3 and ZEB1.

High Mobility Group A1 (HMGA1): Structure, Biological Function, and Therapeutic Potential

High mobility group A1 (HMGA1) is a nonhistone chromatin structural protein characterized by no transcriptional activity. It mainly plays a regulatory role by modifying the structure of DNA. A large number of studies have confirmed that HMGA1 regulates genes related to tumours in the reproductive system, digestive system, urinary system and haematopoietic system. HMGA1 is rare in adult cells and increases in highly proliferative cells such as embryos. After being stimulated by external factors, it will produce effects through the Wnt/β-catenin, PI3K/Akt, Hippo and MEK/ERK pathways. In addition, HMGA1 also affects the ageing, apoptosis, autophagy and chemotherapy resistance of cancer cells, which are linked to tumorigenesis. In this review, we summarize the mechanisms of HMGA1 in cancer progression and discuss the potential clinical application of targeted HMGA1 therapy, indicating that targeted HMGA1 is of great significance in the diagnosis and treatment of malignancy.

RETRACTED: Pancreatic cancer cells-derived exosomal long non-coding RNA CCAT1/microRNA-138-5p/HMGA1 axis promotes tumor angiogenesis

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). This article has been retracted at the request of the Editor-in-Chief. Concern was raised about the reliability of the Western blot results in Figs. 2B and 5I+J, which appear to have the same eyebrow shaped phenotype as many other publications tabulated here (https://docs.google.com/spreadsheets/d/149EjFXVxpwkBXYJOnOHb6RhAqT4a2llhj9LM60MBffM/edit#gid=0). In addition, Fig. 4B appears to show a digital composition of xenografted tumors. The journal requested the corresponding author comment on these concerns and provide the raw data. However the authors were not able to satisfactorily fulfil this request and therefore the Editor-in-Chief decided to retract the article.

High mobility group A1 expression shows negative correlation with recurrence time in patients with glioblastoma multiforme

The aim of this study was to explore the difference in high mobility group A1 (HMGA1) expression and isocitrate dehydrogenase (IDH) 1 R132H point mutation in initial and recurrent glioblastoma multiforme (GBM), and to further identify whether the expression of HMGA1 has a role in the malignant progression of GBM. Paired initial and recurrent GBM specimens from the same patient were evaluated using immunohistochemical analysis. The association between HMGA1 expression and progression-free survival time (PFST) was analyzed. Three patients were confirmed with IDH-1 R132H mutations in both initial and recurrent groups (3/25, 12%). There was a significant difference in HMGA1 expression between initial and recurrent GBM (P=0.002), and patients with tumors expressing HMGA1 at higher level had a significantly shorter PFST (7.3 months versus 11.1months; P=0.044). Our study indicates that recurrent GBM express HMGA1 at a higher level and that HMGA1 overexpressoin is associated with shorter PFST in patients with GBM. These findings suggest that HMGA1 potentially plays an important role in the treatment of GBM.