scholarly journals BRD4 is a novel therapeutic target for liver fibrosis

2015 ◽  
Vol 112 (51) ◽  
pp. 15713-15718 ◽  
Author(s):  
Ning Ding ◽  
Nasun Hah ◽  
Ruth T. Yu ◽  
Mara H. Sherman ◽  
Chris Benner ◽  
...  

Liver fibrosis is characterized by the persistent deposition of extracellular matrix components by hepatic stellate cell (HSC)-derived myofibroblasts. It is the histological manifestation of progressive, but reversible wound-healing processes. An unabated fibrotic response results in chronic liver disease and cirrhosis, a pathological precursor of hepatocellular carcinoma. We report here that JQ1, a small molecule inhibitor of bromodomain-containing protein 4 (BRD4), a member of bromodomain and extraterminal (BET) proteins, abrogate cytokine-induced activation of HSCs. Cistromic analyses reveal that BRD4 is highly enriched at enhancers associated with genes involved in multiple profibrotic pathways, where BRD4 is colocalized with profibrotic transcription factors. Furthermore, we show that JQ1 is not only protective, but can reverse the fibrotic response in carbon tetrachloride-induced fibrosis in mouse models. Our results implicate that BRD4 can act as a global genomic regulator to direct the fibrotic response through its coordinated regulation of myofibroblast transcription. This suggests BRD4 as a potential therapeutic target for patients with fibrotic complications.

Reports ◽  
2021 ◽  
Vol 4 (2) ◽  
pp. 17
Author(s):  
Vikrant Rai ◽  
Devendra K. Agrawal

Hepatocellular carcinoma (HCC), accounting for more than 90% of cases of primary liver cancer, is the third most common cause of cancer-related death worldwide. Chronic inflammation precedes the development of cirrhosis and HCC. TREM (triggering receptor expressed on myeloid cell)-1 is an inflammatory marker and amplifier of inflammation that signals through PI3K and ERK1/2 to activate transcription factors, resulting in increased secretion of pro-inflammatory cytokines, causing chronic inflammation and predisposing the liver to carcinogenesis. Thus, targeting TREM-1 in HCC might be a potential therapeutic target. A low level of vitamin D has been associated with chronic inflammation and poor prognosis in HCC. Thus, we evaluated the effect of vitamin D on TREM-1 expression in the HCC cell line. Additionally, the effects of high mobility group box-1, lipopolysaccharide, and transcription factor PU.1 on the expression of TREM-1 in normal liver cells and HCC cells have been investigated in the presence and absence of vitamin D. The results showed increased expression of TREM-1 in HCC cells and with IL-6, TNF-α, LPS, and rHMGB-1 and decreased expression with calcitriol. Calcitriol also attenuated the effect of IL-6, TNF-α, LPS, and rHMGB-1 on TREM-1. Calcitriol treatment attenuated the proliferation, migration, and invasion of HCC cells. These results (in vitro) provide molecular and biochemical evidence that calcitriol significantly attenuates the expression of mediators of inflammation, and thus might be used therapeutically together with conventional treatment to delay the progression of HCC. Additionally, the negative regulation of TREM-1 by PU.1 suggests PU.1 as a potential therapeutic target.


2018 ◽  
Vol 38 (1) ◽  
Author(s):  
Jin-yan Wang ◽  
Qian Zhang ◽  
Dan-dan Wang ◽  
Wei Yan ◽  
Huan-huan Sha ◽  
...  

MiRNAs, small non-coding RNA molecules, were recognized to be associated with the incidence and development of diverse neoplasms. MiRNAs were small non-coding RNAs that could regulate post-transcriptional level by binding to 3′-UTR of target mRNAs. Amongst which, miR-29a was demonstrated that it had significant impact on oncogenicity in various neoplasms through binding to critical genes which enhanced or inhibited the progression of cancers. MiR-29a participated in kinds of physiological and pathological processes, including virus replication, cell proliferation, differentiation, apoptosis, fibrosis, angiogenesis, tumorigenicity, metastasis, drug-resistance, and so on. According to its sufficient sensitivity and specificity, many studies showed that miR-29a might serve as a potential therapeutic target and promising biomarker in various tumors. In this review, we discussed the functions of miR-29a and its potential application in the diagnosis, treatment and stages of carcinoma, which could provide additional insight to develop a novel therapeutic strategy.


Oncotarget ◽  
2017 ◽  
Vol 8 (37) ◽  
pp. 61327-61337 ◽  
Author(s):  
Junqing Wang ◽  
Yunyun Zhou ◽  
Xiaochun Fei ◽  
Xunhua Chen ◽  
Rui Chen ◽  
...  

Oncotarget ◽  
2015 ◽  
Vol 6 (27) ◽  
pp. 24163-24177 ◽  
Author(s):  
Dong-Sheng Zhou ◽  
Hong-Bo Wang ◽  
Zhong-Guo Zhou ◽  
Yao-Jun Zhang ◽  
Qian Zhong ◽  
...  

Author(s):  
Yousef M.O. Alhammad ◽  
Maithri M. Kashipathy ◽  
Anuradha Roy ◽  
Jean-Philippe Gagné ◽  
Peter McDonald ◽  
...  

ABSTRACTSevere acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and other SARS-like-CoVs encode 3 tandem macrodomains within non-structural protein 3 (nsp3). The first macrodomain, Mac1, is conserved throughout CoVs, and binds to and hydrolyzes mono-ADP-ribose (MAR) from target proteins. Mac1 likely counters host-mediated anti-viral ADP-ribosylation, a posttranslational modification that is part of the host response to viral infections. Mac1 is essential for pathogenesis in multiple animal models of CoV infection, implicating it as a virulence factor and potential therapeutic target. Here we report the crystal structure of SARS-CoV-2 Mac1 in complex with ADP-ribose. SARS-CoV-2, SARS-CoV and MERS-CoV Mac1 exhibit similar structural folds and all 3 proteins bound to ADP-ribose with low μM affinities. Importantly, using ADP-ribose detecting binding reagents in both a gel-based assay and novel ELISA assays, we demonstrated de-MARylating activity for all 3 CoV Mac1 proteins, with the SARS-CoV-2 Mac1 protein leading to a more rapid loss of substrate compared to the others. In addition, none of these enzymes could hydrolyze poly-ADP-ribose. We conclude that the SARS-CoV-2 and other CoV Mac1 proteins are MAR-hydrolases with similar functions, indicating that compounds targeting CoV Mac1 proteins may have broad anti-CoV activity.IMPORTANCESARS-CoV-2 has recently emerged into the human population and has led to a worldwide pandemic of COVID-19 that has caused greater than 900 thousand deaths worldwide. With, no currently approved treatments, novel therapeutic strategies are desperately needed. All coronaviruses encode for a highly conserved macrodomain (Mac1) that binds to and removes ADP-ribose adducts from proteins in a dynamic post-translational process increasingly recognized as an important factor that regulates viral infection. The macrodomain is essential for CoV pathogenesis and may be a novel therapeutic target. Thus, understanding its biochemistry and enzyme activity are critical first steps for these efforts. Here we report the crystal structure of SARS-CoV-2 Mac1 in complex with ADP-ribose, and describe its ADP-ribose binding and hydrolysis activities in direct comparison to SARS-CoV and MERS-CoV Mac1 proteins. These results are an important first step for the design and testing of potential therapies targeting this unique protein domain.


Sign in / Sign up

Export Citation Format

Share Document