Long noncoding RNA SENCR facilitates the progression of acute myeloid leukemia through the miR-4731-5p/IRF2 pathway

BACKGROUND

Acute myeloid leukemia (AML) is a type of hematological tumor caused by malignant clone hematopoietic stem cells. The relationship between lncRNAs and tumor occurrence and progression has been gaining attention. Research has shown that Smooth muscle and endothelial cell-enriched migration/differentiation-associated lncRNA (SENCR) is abnormally expressed in various diseases, whereas its role in AML is still poorly understood.

METHODS

The expression of SENCR, microRNA-4731-5p (miR-4731-5p) and Interferon regulatory factor 2 (IRF2) were measured using qRT-PCR. The proliferation, cycle and apoptosis of AML cells with or without knockdown of SENCR were detected by CCK-8 assay, EdU assay, flow cytometry, western blotting and TUNEL assay, respectively. Consistently, SENCR knockdown was impaired the AML progression in immunodeficient mice. In addition, the binding of miR-4731-5p to SENCR or IRF2 was confirmed by luciferase reporter genes assay. Finally, rescue experiments were conducted to confirm the role of SENCR/miR-4731-5p/IRF2 axis in AML.

RESULTS

SENCR is highly expressed in AML patients and cell lines. The patients with high SENCR expression had poorer prognosis compared with those with low SENCR expression. Interestingly, knockdown of SENCR inhibits the growth of AML cells. Further results demonstrated that the reduction of SENCR slows the progression of AML in vivo. SENCR could function as a competing endogenous RNA (ceRNA) to negatively regulate miR-4731-5p in AML cells. Furthermore, IRF2 was validated as a direct target gene of miR-4731-5p in AML cells.

CONCLUSIONS

Our findings underscore the important role of SENCR in regulating the malignant phenotype of AML cells by targeting the miR-4731-5p/IRF2 axis.

LncRNA SENCR overexpression attenuated the proliferation, migration and phenotypic switching of vascular smooth muscle cells in aortic dissection via the miR-206/myocardin axis

BACKGROUND AND AIMS

Smooth muscle and endothelial cell-enriched migration/differentiation-associated lncRNA (SENCR) has been reported to be associated with some cardiovascular diseases; however, its function and exact molecular mechanism in aortic dissection (AD) remain undefined. Thus, we investigated the effects of SENCR on AD and its potential mechanisms.

METHODS AND RESULTS

SENCR expression in aortic media specimens from AD patients was detected by quantitative real-time PCR (qPCR). The roles of SENCR in vascular smooth muscle cell (VMSC) proliferation and migration as well as in the regulation of contractile phenotype genes were studied using CCK-8, wound healing, Transwell, qPCR and Western blot assays. Dual-luciferase reporter assays were performed to identify the regulatory correlation between SENCR, miR-206 and myocardin. Furthermore, mouse AD models were constructed with ApoE^-/- mice, and the effect of upregulated SENCR on phenotypic switching in the AD model was detected using hematoxylin and eosin (H&E) staining and immunohistochemistry (IHC) assays. SENCR overexpression inhibited VSMC proliferation, migration and synthetic phenotype-related gene expression; decreased miR-206 expression; increased myocardin expression; and suppressed rupture of the aortic media in mice. SENCR knockdown had the opposite effects. Our results further suggested that miR-206 upregulation could reverse the inhibitory roles of SENCR upregulation and that myocardin upregulation could restore the function of SENCR upregulation in VSMCs. Dual-luciferase reporter assays confirmed that SENCR regulated miR-206, which directly targeted myocardin in VSMCs.

CONCLUSION

SENCR overexpression suppressed VMSC proliferation and migration, maintained the contractile phenotype and suppressed aortic dilatation via the miR-206/myocardin axis.

Long Non-Coding RNAs Gene Variants as Molecular Markers for Diabetic Retinopathy Risk and Response to Anti-VEGF Therapy

Background

Long non-coding RNAs (lncRNAs) play essential roles in molecular diagnosis and therapeutic response in several diseases.

Purpose

For the first time, we aimed to evaluate the association of four lncRNAs TUG1 (rs7284767G/A), MIAT (rs1061540T/C), MALAT1 (rs3200401C/T), and SENCR (rs12420823C/T) variants with susceptibility to diabetic retinopathy (DR), disease severity, and early therapeutic response to intravitreous anti-vascular endothelial growth factor aflibercept therapy.

Patients and Methods

This case-control study enrolled 126 adult patients with type 2 diabetes. TaqMan assays using Real-Time PCR were run for genotyping. Multivariable regression analyses were applied to assess the role of each polymorphism after the adjustment of covariates.

Results

Carriers of TUG1 A/G and MIAT T/C and C/C genotypes were more likely to develop DR [OR=3.15 (95% CI=1.15–8.64), and OR=4.31 (95% CI=1.78–10.47)], while MALAT1 T/C conferred protection (OR=0.40, 95% CI=0.16–0.99). For TUG1, MALAT1, MIAT, and SENCR genotype combinations, GTCT and GCCC had a higher disease risk (P=0.012). For disease severity, MIAT T/T homozygosity was associated with higher DR grade [33.3% (T/T) vs 10% (C/C) and 4.2% (C/T) carriers, P=0.012]. Otherwise, patients with the SENCR T variant exhibited better pre-treatment best-corrected visual acuity level (p=0.021). Following aflibercept administration, carrying the TUG1 A or MIAT T/C was associated with a poor therapeutic response (OR=5.02, 95% CI=1.60–15.76, and OR=10.23, 95% CI=1.51–69.15, respectively).

Conclusion

The lncRNAs TUG1 (rs7284767G/A) and MIAT (rs1061540T/C) were associated with increased DR susceptibility and poor response to aflibercept treatment, while MALAT1 (rs3200401C/T) conferred protection to DR. These genetic determinants could be useful in DR risk stratification and pharmacogenetics after validation in large-scale studies.

11q24.2q24.3 microdeletion in two families presenting features of Jacobsen syndrome, without intellectual disability: Role of FLI1, ETS1, and SENCR long noncoding RNA

This report presents two families with interstitial 11q24.2q24.3 deletion, associated with malformations, hematologic features, and typical facial dysmorphism, observed in Jacobsen syndrome (JS), except for intellectual disability (ID). The smallest 700 Kb deletion contains only two genes: FLI1 and ETS1, and a long noncoding RNA, SENCR, narrowing the minimal critical region for some features of JS. Consistent with recent literature, it adds supplemental data to confirm the crucial role of FLI1 and ETS1 in JS, namely FLI1 in thrombocytopenia and ETS1 in cardiopathy and immune deficiency. It also supports that combined ETS1 and FLI1 haploinsufficiency explains dysmorphic features, notably ears, and nose anomalies. Moreover, it raises the possibility that SENCR, a long noncoding RNA, could be responsible for limb defects, because of its early role in endothelial cell commitment and function. Considering ID and autism spectrum disorder, which are some of the main features of JS, a participation of ETS1, FLI1, or SENCR cannot be excluded. But, considering the normal neurodevelopment of our patients, their role would be either minor or with an important variability in penetrance. Furthermore, according to literature, ARHGAP32 and KIRREL3 seem to be the strongest candidate genes in the 11q24 region for other Jacobsen patients.

Current status and strategies of long noncoding RNA research for diabetic cardiomyopathy

Long noncoding RNAs (lncRNAs) are endogenous RNA transcripts longer than 200 nucleotides which regulate epigenetically the expression of genes but do not have protein-coding potential. They are emerging as potential key regulators of diabetes mellitus and a variety of cardiovascular diseases. Diabetic cardiomyopathy (DCM) refers to diabetes mellitus-elicited structural and functional abnormalities of the myocardium, beyond that caused by ischemia or hypertension. The purpose of this review was to summarize current status of lncRNA research for DCM and discuss the challenges and possible strategies of lncRNA research for DCM. A systemic search was performed using PubMed and Google Scholar databases. Major conference proceedings of diabetes mellitus and cardiovascular disease occurring between January, 2014 to August, 2018 were also searched to identify unpublished studies that may be potentially eligible. The pathogenesis of DCM involves elevated oxidative stress, myocardial inflammation, apoptosis, and autophagy due to metabolic disturbances. Thousands of lncRNAs are aberrantly regulated in DCM. Manipulating the expression of specific lncRNAs, such as H19, metastasis-associated lung adenocarcinoma transcript 1, and myocardial infarction-associated transcript, with genetic approaches regulates potently oxidative stress, myocardial inflammation, apoptosis, and autophagy and ameliorates DCM in experimental animals. The detail data regarding the regulation and function of individual lncRNAs in DCM are limited. However, lncRNAs have been considered as potential diagnostic and therapeutic targets for DCM. Overexpression of protective lncRNAs and knockdown of detrimental lncRNAs in the heart are crucial for defining the role and function of lncRNAs of interest in DCM, however, they are technically challenging due to the length, short life, and location of lncRNAs. Gene delivery vectors can provide exogenous sources of cardioprotective lncRNAs to ameliorate DCM, and CRISPR–Cas9 genome editing technology may be used to knockdown specific lncRNAs in DCM. In summary, current data indicate that LncRNAs are a vital regulator of DCM and act as the promising diagnostic and therapeutic targets for DCM.

Association of the rs555172 polymorphism in SENCR long non-coding RNA and atherosclerotic coronary artery disease

Introduction: Variants in long non-coding RNAs (lncRNAs) have been implicated as potential biomarkers in prediction of complex disorders such as coronary artery disease (CAD). Studies considering the impact of the SENCR antisense lncRNAs on CAD have not established yet in Iranian population. This study aimed to investigate the association between SENCR rs555172 polymorphism and CAD in south Iranian population.

Methods: Amplification refractory mutation system-polymerase chain reaction (ARMS-PCR) was performed to determine the allele and the genotype distribution of SENCR lncRNA polymorphism in 150 patients with CAD compared with 149 healthy controls through this hospital-based case-control study.

Results: The frequency of AA, AG, and GG genotypes in cases were 32.7%, 44.7%, and 22.6%, and in controls were 26.8%, 49%, and 24.2%, respectively. Association was not found with any of the genotypes in comparison of cases and controls. The allelic frequencies did not differ between cases and controls. Cross-tabulating the population based on the gender, the frequency of the GG genotype was significantly higher among women of the case group compared to men. The difference was not seen in the control group between two sexes.

Conclusion: The results suggested that the SENCR gene polymorphism did not confer susceptibility to CAD.