Background: SIRT7 is one of the histone deacetylases and is NAD-dependent. It forms a complex with ETS-like transcription factor 4 (ELK4), which deacetylates H3K18ac and works as a transcriptional suppressor. Overexpression of SIRT7 and deacetylation of H3K18ac have been shown to be associated with aggressive clinical behavior in some cancers, including hepatocellular carcinoma (HCC). The present study investigated the immunohistochemical expression of SIRT7, H3K18ac, and ELK4 in hepatocellular carcinoma.

Methods: A total of 278 HCC patients were enrolled in this study. Tissue microarray blocks were made from existing paraffin-embedded blocks. Immunohistochemical expressions of SIRT7, H3K18ac and ELK4 were scored and analyzed.

Results: High SIRT7 (p = .034), high H3K18ac (p = .001), and low ELK4 (p = .021) groups were associated with poor outcomes. Age < 65 years (p = .028), tumor size ≥ 5 cm (p = .001), presence of vascular emboli (p = .003), involvement of surgical margin (p = .001), and high American Joint Committee on Cancer stage (III&V) (p < .001) were correlated with worse prognoses. In multivariate analysis, H3K18ac (p = .001) and ELK4 (p = .015) were the significant independent prognostic factors.

Conclusions: High SIRT7 expression with poor overall survival implies that deacetylation of H3K18ac contributes to progression of HCC. High H3K18ac expression with poor prognosis is predicted due to a compensation mechanism. In addition, high ELK4 expression with good prognosis suggests another role of ELK4 as a tumor suppressor beyond SIRT7's helper. In conclusion, we could assume that the H3K18ac deacetylation pathway is influenced by many other factors.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5042897PMC
http://dx.doi.org/10.4132/jptm.2016.05.20DOI Listing

Publication Analysis

Top Keywords

sirt7 h3k18ac
12
h3k18ac elk4
12
h3k18ac
9
elk4
8
immunohistochemical expression
8
hepatocellular carcinoma
8
deacetylation h3k18ac
8
high sirt7
8
high h3k18ac
8
h3k18ac 001
8

Similar Publications

Mechanistic insights into SIRT7 and EZH2 regulation of cisplatin resistance in bladder cancer cells.

Cell Death Dis

December 2024

Key laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Department of Urology, Peking University Cancer Hospital & Institute, Beijing, 100142, China.

Cisplatin (CDDP) resistance has been established to significantly impact Bladder Cancer (BCa) therapy. On the other hand, the crucial regulatory involvement of SIRT7 and EZH2 in bladder cancer development is well known. Herein, the collaborative regulatory roles and underlying mechanisms of SIRT7 and EZH2 in CDDP resistance in bladder cancer were explored.

View Article and Find Full Text PDF

Diabetic kidney disease (DKD), a primary microvascular complication arising from diabetes, may result in end-stage renal disease. Epigenetic regulation of endothelial mesenchymal transition (EndMT) has been recently reported to exert function in metabolic memory and DKD. Here, we investigated the mechanism which Sirt7 modulated EndMT in human glomerular endothelial cells (HGECs) in the occurrence of metabolic memory in DKD.

View Article and Find Full Text PDF
Article Synopsis
  • Acetaminophen (APAP) is commonly used to manage pain and fever in pregnant women, but research suggests it may negatively impact fetal development, specifically oocyte formation.
  • In a study, pregnant mice were given APAP, which resulted in meiotic problems in fetal oocytes, including delays in development and defects in genetic recombination due to its metabolite, NAPQI.
  • The adverse effects on oocyte health and female fertility in offspring were counteracted by co-treatment with NAD supplements, highlighting their potential therapeutic benefits during pregnancy.
View Article and Find Full Text PDF

IGF1R-phosphorylated PYCR1 facilitates ELK4 transcriptional activity and sustains tumor growth under hypoxia.

Nat Commun

September 2023

Endoscopy Center, Department of Gastroenterology, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, China.

The proline synthesis is importantly involved in tumor growth under hypoxia, while the underlying mechanism remains to be further investigated. Here we show that pyrroline-5-carpoxylate reductase-1 (PYCR1), displaying a constant nuclear localization, is phosphorylated by nuclear IGF1R at Tyrosine 135 under hypoxia; this phosphorylation promotes the binding of PYCR1 to ELK4 and thus PYCR1 recruitment to ELK4-targeted genes promoter. Under hypoxia, ELK4-binding ability and enzymatic activity of PYCR1 are both required for ELK4-Sirt7-mediated transcriptional repression and cell growth maintenance, in which PYCR1-catalyzed NAD production stimulates the deacetylation activity of Sirt7 on H3K18ac that restrains genes transcription.

View Article and Find Full Text PDF

Disruption of sirtuin 7 in zebrafish facilitates hypoxia tolerance.

J Biol Chem

August 2023

State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China; University of Chinese Academy of Sciences, Beijing, China; The Innovation of Seed Design, Chinese Academy of Sciences, Wuhan, China. Electronic address:

SIRT7 is a member of the sirtuin family proteins with nicotinamide adenine dinucleotide (NAD)-dependent histone deacetylase activity, which can inhibit the activity of hypoxia-inducible factors independently of its enzymatic activity. However, the role of SIRT7 in affecting hypoxia signaling in vivo is still elusive. Here, we find that sirt7-null zebrafish are more resistant to hypoxic conditions, along with an increase of hypoxia-responsive gene expression and erythrocyte numbers, compared with their wildtype siblings.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!