Circadian clock component PER2 negatively regulates CD4+ T cell IFN-γ production in ulcerative colitis.

Period circadian clock 2 (PER2) is involved in the pathogenesis of various inflammatory and autoimmune diseases. However, there are gaps in our understanding of the role of PER2 in regulating CD4+ T cells beyond its time-keeping function in ulcerative colitis (UC) pathogenesis. Our findings revealed PER2 was predominantly expressed in CD4+ T cells, while it was significantly decreased in the inflamed mucosa and peripheral blood CD4+ T cells of UC patients compared with that in Crohn's disease (CD) patients and healthy controls (HC). Notably, PER2 expression was significantly recovered in UC patients in remission (R-UC) compared to that in active UC patients (A-UC) but not in CD patients. It was negatively correlated with the Ulcerative Colitis Endoscopic Index of Severity (UCEIS), Crohn's Disease Activity Index (CDAI), Simple Endoscopic Score for Crohn's disease (SES-CD), and C-reactive protein (CRP), respectively. Overexpression of PER2 markedly inhibited IFN-γ production in UC CD4+ T cells. RNA-seq analysis showed that overexpression of PER2 could repress the expression of a disintegrin and metalloproteinase 12 (ADAM12), a costimulatory molecule that determines Th1 cell fate. Mechanistically, cleavage under targets and tagmentation (CUT&Tag) analysis revealed that PER2 down-regulated ADAM12 expression by reducing its binding activity, thereby suppressing IFN-γ production in UC CD4+ T cells. Additionally, our data further demonstrated that ADAM12 was upregulated in CD4+ T cells and inflamed mucosa of A-UC patients compared to HC. Our study reveals a critical role of PER2 in regulating CD4+ T cell differentiation and highlights its potential as a therapeutic target for UC treatment.

Tumor-suppressor p53 specifically binds to miR-29c-3p and reduces ADAM12 expression in hepatocellular carcinoma.

BACKGROUND: Hepatocellular carcinoma (HCC) is an extremely aggressive malignant tumor associated with high migratory and invasive potential. The present study intends to explore regulatory mechanism of p53/microRNA (miR)-29c-3p/A disintegrin and metalloproteinase 12 (ADAM12) axis in HCC based on clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) technology. METHODS: Putative miR-29c-3p binding sites on ADAM12 3'UTR were verified by a luciferase assay. The binding affinity of p53 to miR-29c-3p was assessed based on CRISPR/Cas9 technology to construct a p53 knockout (p53-/-) HCCLM3 cell line. Furthermore, the effect of p53/miR-29c-3p/ADAM12 was assessed on maligant phenotypes in vitro and tumor formation and metastasis in nude mice. RESULTS: ADAM12 was highly expressed but miR-29c-3p was poorly expressed in HCC. miR-29c-3p inhibited migratory and invasive abilities of HCC cells by targeting ADAM12 expression. p53 was found to target and upregulate miR-29c-3p, thus downregulating ADAM12 and conferring inhibitory effect on HCC cell activities. Moreover, ADAM12 knockout or p53 overexpression reduced HCC tumor formation and metastasis, which were reversed by further silencing of miR-29c-3p. CONCLUSION: The identification of the p53/miR-29c-3p/ADAM12 axis in migration and invasion of HCC may potentially further our understanding of mechanisms underpinning HCC, and also bear translational value as novel molecular targets.

The Role of LINC00284 in the Development of Thyroid Cancer via Its Regulation of the MicroRNA-30d-5p-Mediated ADAM12/Notch Axis.

Thyroid cancer is a commonly diagnosed endocrine malignancy with increasing incidence worldwide. Long noncoding RNAs (lncRNAs) are known to function in the invasion and metastasis of thyroid cancer. According to the GSE66783 microarray dataset, long intergenic nonprotein coding RNA 284 (LINC00284) is aberrantly upregulated in thyroid cancer tissues. However, information regarding the specific role of LINC00284 in thyroid cancer remains elusive. Therefore, the current study set out to determine the role of LINC00284 in the development of thyroid cancer, along with an investigation of the underlying molecular mechanism. In parallel with the microarray data from GSE66783, LINC00284 was observed to be expressed at high levels in thyroid cancer cell lines. Moreover, loss-of-function experiments revealed that the downregulation of LINC00284 reduced aldehyde dehydrogenase (ALDH) activity and thyroid cancer cell proliferation, colony formation, and invasiveness, which promoted cell apoptosis. Mechanistically, using dual-luciferase reporter, RNA pull-down, and RNA immunoprecipitation (RIP) assays, LINC00284 was identified to competitively bind to microRNA-30d-5p (miR-30d-5p), which was observed to be expressed at low levels in thyroid cancer tissues and cells and directly targets the oncogene a disintegrin and metalloproteinase 12 (ADAM12). Overexpression of miR-30d-5p exerted tumor-suppressive effects on the malignant activity of thyroid cancer cells, changes that were reversed by LINC00284 overexpression or ADAM12 overexpression. Furthermore, LINC00284 activated the Notch signaling pathway by competitively binding to miR-30d-5p and increasing the expression of ADAM12. Finally, by performing in vivo experiments, we found that LINC00284 silencing or miR-30d-5p overexpression suppressed the tumorigenic ability of thyroid cancer cells and that overexpression of miR-30d-5p inhibited the LINC00284-induced tumorigenesis of thyroid cancer cells. Collectively, our findings indicate that LINC00284 competitively binds to miR-30d-5p and activates the ADAM12-dependent Notch signaling pathway, thereby promoting the development of thyroid cancer.

Role of genetics in peripheral arterial disease outcomes; significance of limb-salvage quantitative locus-1 genes.

Peripheral artery disease is a major health care problem with significant morbidity and mortality. Humans with peripheral artery disease exhibit two major and differential clinical manifestations - intermittent claudication and critical limb ischemia. Individuals with intermittent claudication or critical limb ischemia have overlapping risk factors and objective measures of blood flow. Hence, we hypothesized that variation in genetic make-up may be an important determinant in the severity of peripheral artery disease. Previous studies have identified polymorphism in genes, contributing to extent of atherosclerosis but much less is known about polymorphisms associated with genes that can influence peripheral artery disease severity. This review outlines some of the progress made up-to-date to unravel the molecular mechanisms underlining differential peripheral artery disease severity. By exploring the recovery phenotype of different mouse strains following experimental peripheral artery disease, our group identified the limb salvage-associated quantitative trait locus 1 on mouse chromosome 7 as the first genetic modifier of perfusion recovery and tissue necrosis phenotypes. Furthermore, a number of genes within LSq-1, such as ADAM12, IL-21Rα, and BAG3 were identified as genetic modifiers of peripheral artery disease severity that function through preservation of endothelial and skeletal muscle cells during ischemia. Taken together, these studies suggest manipulation of limb salvage-associated quantitative trait locus 1 genes show great promise as therapeutic targets in the management of peripheral artery disease. Impact statement Peripheral artery disease (PAD) is a major health care problem with significant morbidity and mortality. Individuals with similar atherosclerosis burden do display different severity of disease. This review outlines some of the progress made up-to-date in unraveling the molecular mechanisms underlining differential PAD severity with a focus on the role of the Limb Salvage-associated Quantitative trait locus 1 (LSq-1), a key locus in adaptation to ischemia in PAD.

ADAM12 and PAPP-A: Candidate regulators of trophoblast invasion and first trimester markers of healthy trophoblasts.

Proper placental development and function is crucial for a healthy pregnancy, and there has been substantial research to identify markers of placental dysfunction for the early detection of pregnancy complications. Low first-trimester levels of a disintegrin and metalloproteinase 12 (ADAM12) and pregnancy-associated plasma protein-A (PAPP-A) have been consistently associated with the subsequent development of preeclampsia and fetal growth restriction. These molecules are both metalloproteinases secreted by the placenta that cleave insulin-like growth factor binding proteins (IGFBPs), although ADAM12 also has numerous other substrates. Recent work has identified ADAM12, and particularly its shorter variant, ADAM12S, as a regulator of the migration and invasion of trophoblasts into the lining of the uterus, a critical step in normal placental development. While the mechanisms underlying this regulation are not yet clear, they may involve the liberation of heparin-binding EGF-like growth factor (HB-EGF) and/or IGFs from IGFBPs. In contrast, there has been relatively little functional work examining PAPP-A or the IGFBP substrates of ADAM12 and PAPP-A. Understanding the functions of these markers and the mechanisms underlying their association with disease could improve screening strategies and enable the development of new therapeutic interventions.

A disintegrin and metalloproteinase 12 (ADAM12) localizes to invasive trophoblast, promotes cell invasion and directs column outgrowth in early placental development.

During pregnancy, stromal- and vascular-remodeling trophoblasts serve critical roles in directing placental development acquiring pro-invasive characteristics. The A Disintegrin and Metalloproteinase (ADAM) family of multifunctional proteins direct cellular processes across multiple organ systems via their intrinsic catalytic, cell adhesive and intracellular signaling properties. ADAM12, existing as two distinct splice variants (ADAM12L and ADAM12S), is highly expressed in the human placenta and promotes cell migration and invasion in several tumor cell lines; however, its role in trophoblast biology is unknown. In this study, ADAM12 was localized to anchoring trophoblast columns in first trimester placentas and to highly invasive extracellular matrix-degrading trophoblasts in placental villous explants. The importance of ADAM12 in directing trophoblast invasion was tested using loss-of and gain-of-function strategies, where siRNA-directed knockdown of ADAM12 inhibited trophoblast cell invasion while over-expression promoted migration and invasion in two trophoblastic cell models. In placental villous explant cultures, siRNA-directed loss of ADAM12 significantly dampened trophoblast column outgrowth. Additionally, we provide functional evidence for the ADAM12S variant in promoting trophoblast invasion and column outgrowth through a mechanism requiring its catalytic activity. This is the first study to assign a function for ADAM12 in trophoblast biology, where ADAM12 may play a central role regulating the behavior of invasive trophoblast subsets in early pregnancy. This study also underlines the importance of ADAM12L and ADAM12S in directing cell motility in normal developmental processes outside of cancer, specifically highlighting a potentially important function of ADAM12S in directing early placental development.

Expression and clinical significance of a disintegrin and metalloproteinase-12 and proliferating cell nuclear antigen in bladder carcinoma / 中国综合临床

Objective To investigate the expression of a dismtegnn and metalloproteinase-12 (ADAM12) and proliferating cell nuclear antigen (PCNA) in human bladder carcinoma,and to explore their correlation with different grades and stages of bladder cancer.Methods Biopsies of 12 normal bladder and 43 bladder tumors were performed.And immunohistochemistry was conducted to detect the expression of ADAM12 and PCNA in the biopsies.Results Positive expression signals of ADAM12 were detected significantly higher inthe bladder cancer biopsies than that in the normal ones (Z =4.879,P ＜ 0.05),and the expression level of ADAM-12 in lower histological grade was significantly higher than that in the moderate and higher histological grades (x2 =22.3685,P ＜ 0.01).Positive expression signals of PCNA were detected significantly higher in the bladder cancer biopsies than that in the normal ones (Z =4.879,P ＜ 0.05)).Those with lower histological grade had a higher expression level of PCNA when compared with the moderate and higher histological grades (x2 =10.665,P =0.0137).The expression of ADAM-12 was positively correlated with PCNA in bladder cancer (r =1.000,P ＜ 0.0001).Conclusion The over expression of ADAM12 and PCNA maybe play an important role in development of the bladder tumors.And ADAM12 may be a promising biomarker of bladder cancer in the clinical behavior.