LncRNA HCG11/miR-579-3p/MDM2 axis modulates malignant biological properties in pancreatic carcinoma via Notch/Hes1 signaling pathway

Involvement of circ_0029407 in Caerulein-Evoked Cytotoxicity in Human Pancreatic Cells via the miR-579-3p/TLR4/NF-κB Pathway

Acute pancreatitis (AP) is the most prevalent gastrointestinal inflammatory disease. Circular RNAs (circRNAs) are implicated in the development of AP. Here, we identified the precise action of circ_0029407 in AP development. Human pancreatic epithelial cells (HPECs) were stimulated with caerulein. Cell viability, proliferation, and apoptosis were gauged by Cell Counting Kit-8 (CCK-8), 5-ethynyl-2'-deoxyuridine (EdU), and flow cytometry assays, respectively. Circ_0029407, microRNA (miR)-579-3p, and toll-like receptor 4 (TLR4) were quantified by a qRT-PCR or western blot assay. Dual-luciferase reporter and RNA pull-down assays were performed to evaluate the direct relationship between miR-579-3p and circ_0029407 or TLR4. Our results indicated that circ_0029407 was markedly overexpressed in AP serum samples and caerulein-stimulated HPECs. Reduction of circ_0029407 attenuated caerulein-imposed HPEC damage by promoting cell proliferation and repressing cell apoptosis and inflammation. Mechanistically, circ_0029407 contained a miR-579-3p binding site, and miR-579-3p downregulation reversed the effect of circ_0029407 reduction on caerulein-imposed HPEC damage. TLR4 was identified as a direct and functional target of miR-579-3p, and TLR4 overexpression reversed the impact of miR-579-3p upregulation on attenuating caerulein-imposed HPEC damage. Moreover, circ_0029407 regulated the TLR4/nuclear factor NF-kappaB (NF-κB) signaling by acting as a competing endogenous RNA (ceRNA) for miR-579-3p. Our study suggests that circ_0029407 regulates caerulein-imposed cell injury in human pancreatic cells at least in part via the TLR4/NF-κB signaling pathway by functioning as a ceRNA for miR-579-3p.

The Expression Analysis of Long Non-coding RNAs Related to Wnt/β-Catenin Signaling in Pancreatic Cancer Patients

Background The oncogenic Wnt/β-catenin signaling plays a critical role in carcinogenesis, prognosis, and resistance to therapy. Pancreatic cancer (PC) has high mortality because of its poor prognosis. Several studies have suggested that lncRNAs are directly involved in the development and progression of PC as well as in Wnt/β-catenin signaling. In this study, we investigated and compared the expression of Wnt/β-catenin signaling-related ZFAS1 and HCG11 lncRNAs, and their targets, CTNNB1 and IGF2BP1 genes in the blood of patients with PC and healthy individuals. A total of 47 PC patients and 50 healthy individuals participated in this study. RNA was extracted from the peripheral blood samples of participants, and cDNA was synthesized. The expression level of the selected genes was quantified by real-time PCR. The expression of HCG11 lncRNA and CTNNB1 genes in patients with PC was significantly upregulated compared to healthy individuals, and the expression of the ZFAS1 lncRNA was significantly downregulated. According to the analysis of the ROC curve, the diagnostic powers of ZFAS1 and CTNNB1 in PC were 0.67 and 0.69, respectively. Altogether, the present study suggests a role for ZFAS1 and HCG11 lncRNAs and CTNNB1 and IGF2BP1 in the pathogenesis of pancreatic cancer. Moreover, the peripheral expression of these lncRNAs may be useful as potential biomarkers for PC.

Interference of MDM2 attenuates vascular endothelial dysfunction in hypertension partly through blocking Notch1/NLRP3 inflammasome pathway

BACKGROUND

Hypertension is a life-threatening disease mainly featured as vascular endothelial dysfunction. This study aims to explore the regulatory role of murine double minute 2 (MDM2) in hypertension and vascular damage.

METHODS

Mice were infused with angiotensin II (AngII) to establish a hypertension mouse model in vivo and AngII-stimulated HUVECs were constructed to simulate the damage of vascular endothelial cells in hypertension in vitro. The plasmids targeting to MDM2 was injected to mice or transfected to HUVECs. qRT-PCR and western blot were performed to detect corresponding gene expression in mice aorta. Blood pressure was measured. H&E and Masson staining were conducted to evaluate histological changes of aorta. Responses to the acetylcholine (ACh) and sodium nitroprusside (SNP) were assessed in aorta. ZO-1 expression and cell apoptosis were detected by immunofluorescence and TUNEL, respectively. Network formation ability was determined employing a tube formation.

RESULTS

MDM2 was upregulated in hypertensive mice. Knockdown of MDM2 inhibited AngII-induced high BP, histological damage, vascular relaxation to Ach, and promoted the levels of p-eNOS and ZO-1 in the aorta in hypertensive mice. MDM2 knockdown inactivated Notch1 signaling and NLRP3 inflammasome, while the inhibitory effect of MDM2 knockdown on NLRP3 inflammasome activation was partly restored by the activation of Notch1. Furthermore, knockdown of MDM2 relieved AngII-induced endothelial dysfunction in HUVECs, as well as suppressing AngII-promoted cell apoptosis. Whereas, the impacts generated by MDM2 knockdown were partly weakened by the activation of Notch1 signaling or NLRP3 inflammasome.

CONCLUSION

In summary, knockdown of MDM2 can attenuate vascular endothelial dysfunction in hypertension, which may be achieved through inhibiting the activation of Notch1 and NLRP3 inflammasome.

Hsa_circ_0031891 targets miR-579-3p to enhance HMGB1 expression and regulate PDGF-BB-induced human aortic vascular smooth muscle cell proliferation, migration, and dedifferentiation

Atherosclerosis (AS) is an underlying cause of the majority of coronary artery disease (CAD), in which proliferation, migration, and dedifferentiation of vascular smooth muscle cells (VSMCs) exert vital roles. It has been reported that circular RNAs (circRNAs) are associated with the VSMCs function. Here, we undertook to explore the biological function and mechanism of hsa_circ_0031891 in a platelet-derived growth factor-BB (PDGF-BB)-induced AS cell model. Hsa_circ_0031891 and microRNA-579-3p (miR-579-3p) levels were detected by real-time quantitative polymerase chain reaction (RT-qPCR). Cell proliferation and migration were detected using Cell Counting Kit-8 (CCK-8), 5-ethynyl-2'-deoxyuridine (EdU), wound healing, and transwell assay. Protein levels of alpha-smooth muscle actin (α-SMA), smooth muscle protein 22-α (SM22-α), Osteopontin, and High mobility group box-1 (HMGB1) were determined using western blot assay. After predicting via a variety of bioinformatics software, the binding between miR-579-3p and hsa_circ_0031891 or HMGB1 was validated using dual-luciferase reporter and RNA pull-down assays. Increased hsa_circ_0031891 and HMGB1 and reduced miR-579-3p were found in CAD patients and PDGF-BB-induced human aortic vascular smooth muscle cells (HA-VSMCs). Moreover, hsa_circ_0031891 deficiency relieved PDGF-BB-mediated HA-VSMC proliferation, migration, and dedifferentiation. Mechanically, hsa_circ_0031891 modulated HMGB1 expression via sponging miR-579-3p. Hsa_circ_0031891 boosted PDGF-BB-induced proliferation, migration, and dedifferentiation partly by regulating the miR-579-3p/HMGB1 axis, hinting at a feasible therapeutic strategy for AS.

Silencing Lnc-HES1-10 Inhibits Osteosarcoma Cells Proliferation, Invasive Ability, and Metastasis

BACKGROUND

Long noncoding RNA (LncRNA) play a vital role in the development and pathophysiology of osteosarcoma (OS). However, the LncRNA activated by HES1-10 in OS has not been furthered investigated. This present study aims to show the possible function of Lnc-HES1-10 in OS.

METHODS

Cell proliferation in vitro were assessed by the MTT assay, whereas the migration and invasion abilities of OS cell lines were measured by wound-healing migration assay and transwell invasion assay, respectively. Quantitative reverse transcriptase polymerase chain reaction and western blot analysis was used to detected the expression level of HES1-10.

RESULTS

The present study demonstrated that the Lnc-HES1-10 is overexpressed in OS and associated with poor prognosis of patients. In addition, the results revealed that Lnc-HES1-10 is overexpressed in MG63 and 143B OS cell lines and promote proliferation on both cell lines in vitro. Furthermore, migration and invasion abilities of MG63 and 143B cells are suppressed after silencing Lnc-HES1-10.

CONCLUSION

Our finding demonstrates that HES1-10 plays a crucial role in regulating OS growth and metastasis.

In Vivo and In Vitro Characterization of the RNA Binding Capacity of SETD1A (KMT2F)

For several histone lysine methyltransferases (HKMTs), RNA binding has been already shown to be a functionally relevant feature, but detailed information on the RNA interactome of these proteins is not always known. Of the six human KMT2 proteins responsible for the methylation of the H3K4 residue, two-SETD1A and SETD1B-contain RNA recognition domains (RRMs). Here we investigated the RNA binding capacity of SETD1A and identified a broad range of interacting RNAs within HEK293T cells. Our analysis revealed that similar to yeast Set1, SETD1A is also capable of binding several coding and non-coding RNAs, including RNA species related to RNA processing. We also show direct RNA binding activity of the individual RRM domain in vitro, which is in contrast with the RRM domain found in yeast Set1. Structural modeling revealed important details on the possible RNA recognition mode of SETD1A and highlighted some fundamental differences between SETD1A and Set1, explaining the differences in the RNA binding capacity of their respective RRMs.

Role of long non-coding RNAs in pancreatic cancer pathogenesis and treatment resistance- A review

Pancreatic cancer (PC) is one of the deadliest cancers associated with poor prognosis. The lack of reliable means of early cancer detection contributes to this disease's dismal prognosis. Long non-coding RNAs (LncRNAs) are protein-free RNAs produced by genome transcription; they play critical roles in gene expression regulation, epigenetic modification, cell proliferation, differentiation, and reproduction. Recent research has shown that lncRNAs play important regulatory roles in PC behaviors, in addition to their recently found functions. Several in-depth investigations have shown that lncRNAs are strongly linked to PC development and progression. Here, we discuss how lncRNAs, which are often overlooked, play many roles as regulators in the molecular mechanism underlying PC. This review also discusses the involved LncRNAs in PC pathogenesis and treatment resistance.

miR579-3p is an inhibitory modulator of neointimal hyperplasia and transcription factors c-MYB and KLF4

Neointimal hyperplasia (IH) is a common vascular pathology that typically manifests in in-stent restenosis and bypass vein graft failure. Smooth muscle cell (SMC) phenotypic switching is central to IH, both regulated by some microRNAs, yet the role of miR579-3p, a scarcely studied microRNA, is not known. Unbiased bioinformatic analysis suggested that miR579-3p was repressed in human primary SMCs treated with different pro-IH cytokines. Moreover, miR579-3p was software-predicted to target both c-MYB and KLF4 - two master transcription factors known to promote SMC phenotypic switching. Interestingly, treating injured rat carotid arteries via local infusion of miR579-3p-expressing lentivirus reduced IH 14 days after injury. In cultured human SMCs, transfection with miR579-3p inhibited SMC phenotypic switching, as indicated by decreased proliferation/migration and increased SMC contractile proteins. miR579-3p transfection downregulated c-MYB and KLF4, and luciferase assays indicated miR579-3p's targeting of the 3'UTRs of the c-MYB and KLF4 mRNAs. In vivo, immunohistochemistry showed that treatment of injured rat arteries with the miR579-3p lentivirus reduced c-MYB and KLF4 and increased SMC contractile proteins. Thus, this study identifies miR579-3p as a previously unrecognized small-RNA inhibitor of IH and SMC phenotypic switch involving its targeting of c-MYB and KLF4. Further studies on miR579-3p may provide an opportunity for translation to develop IH-mitigating new therapeutics.

Circ_0000182 promotes cholesterol synthesis and proliferation of stomach adenocarcinoma cells by targeting miR-579-3p/SQLE axis

BACKGROUND

Circular RNAs (circRNAs) or cholesterol metabolism have been demonstrated to participate in stomach adenocarcinoma (STAD) progression. However, the relationship between circRNAs and cholesterol metabolism in STAD and its underlined mechanism remain unclear.

METHODS

RNA and protein expression levels were detected by qRT-PCR and Western blot. Cell proliferation was assessed by CCK-8, EdU incorporation and colony formation assays. Total cholesterol (TC) and free cholesterol (FC) levels were measured by the corresponding kits. The relationships between circ_0000182 and miR-579-3p or squalene epoxidase (SQLE) mRNA were investigated by bioinformatics analysis, RNA-RNA pull-down, luciferase reporter and RIP assays.

RESULTS

We found that circ_0000182 expression was significantly up-regulated in both STAD tissues and cell lines, and high circ_0000182 expression was correlated with increased tumor size. Circ_0000182 promoted cell proliferation and cholesterol synthesis of STAD cells. Accordingly, cell proliferation, cholesterol synthesis and SQLE expression were significantly inhibited by circ_0000182 knockdown in STAD cells, and these effects were partly reversed by miR-579-3p inhibition or SQLE over-expression. Furthermore, we identified that circ_0000182 acted as a competing endogenous RNA (ceRNA) by sponging miR-579-3p, thereby facilitating SQLE expression, cholesterol synthesis and cell proliferation.

CONCLUSION

Circ_0000182 promotes cholesterol synthesis and proliferation of STAD cells by enhancing SQLE expression via sponging miR-579-3p.

Long non-coding RNA AL137789.1 promoted malignant biological behaviors and immune escape of pancreatic carcinoma cells

Our pre-investigation has revealed that long non-coding RNA (LncRNA) AL137789.1 has the potential to predict the survival of patients with pancreatic carcinoma (PCa). Accordingly, the mechanism underlying the implication of AL137789.1 in PCa is covered in the current study. The non-tumor and paired tumor tissues were collected. Kaplan-Meier curve was employed to estimate the survival of PCa patients with high or low expression of AL137789.1. The proliferation, migration, invasion, and cell cycle of PCa cells were determined, and the cytotoxicity of CD8⁺ T cells was evaluated as well. Levels of AL137789.1, E-cadherin, N-cadherin, and Vimentin were quantified. According to the experimental results, AL137789.1 was highly expressed in PCa and related to a poor prognosis of patients. Overexpressed AL137789.1 enhanced the proliferation, migration, and invasion of PCa cells, increased the cell population at G2/M and S phases yet decreased that in G0/G1 phase, and diminished the cytotoxicity of CD8⁺ T cells. Also, overexpressed AL137789.1 elevated levels of N-cadherin and Vimentin, while lessening E-cadherin levels. However, the silencing of AL137789.1 produced contrary effects. Collectively, lncRNA AL137789.1 plays a tumor-promotive role in PCa by enhancing the progression and immune escape.

The role of lncRNA-mediated ceRNA regulatory networks in pancreatic cancer

Non-coding RNAs (ncRNAs), which occupy the vast majority of human transcripts are known for their inability to encode proteins. NcRNAs consist of a diverse range of RNA species, including long non-coding RNAs (lncRNAs), which have significant meaning for epigenetic modification, post-transcriptional regulation of target genes, molecular interference, etc. The dysregulation of ncRNAs will mediate the pathogenesis of diverse human diseases, like cancer. Pancreatic cancer, as one of the most lethal malignancies in the digestive system that is hard to make a definite diagnosis at an early clinicopathological stage with a miserable prognosis. Therefore, the identification of potential and clinically applicable biomarker is momentous to improve the overall survival rate and positively ameliorate the prognosis of patients with pancreatic carcinoma. LncRNAs as one kind of ncRNAs exert multitudinous biological functions, and act as molecular sponges, relying on microRNA response elements (MREs) to competitively target microRNAs (miRNAs), thereby attenuating the degradation or inhibition of miRNAs to their own downstream protein-coding target genes, also thus regulating the initiation and progression of neoplasms. LncRNAs, which emerge aforementioned function are called competing endogenous RNAs (ceRNAs). Consequently, abundant research of lncRNAs as potential biomarkers is of critical significance for the molecular diagnosis, targeted therapy, as well as prognosis monitoring of pancreatic cancer.

Circ_0001093 promotes glutamine metabolism and cancer progression of esophageal squamous cell carcinoma by targeting miR-579-3p/glutaminase axis

Increasing studies indicate that circular RNAs (circRNAs) play critical roles in tumor metabolism of multiple cancers. However, the contribution of circRNAs in glutamine metabolism of esophageal squamous cell carcinoma (ESCC) remains elusive. The objective of this research was to investigate the role and mechanism of circRNA hsa_circ_0001093 (circ_0001093) in the glutamine metabolism and tumorigenesis of ESCC. Circ_0001093, microRNA-579-3p (miR-579-3p) and glutaminase (GLS) expressions in ESCC tissues and cell lines were measured by qRT-PCR, tissue array or Western blot. Cell proliferation, invasion and migration were assessed by CCK-8 or transwell assays. Glutamine consumption, glutamate and ATP production were detected by indicated assay kits. The relationships between circ_0001093 and miR-579-3p or GLS mRNA were investigated by bioinformatics analysis, RNA pull-down, luciferase reporter and RNA immunoprecipitation (RIP) assays. Here, we found that circ_0001093 expression was up-regulated in ESCC tissues and cell lines. Increased circ_0001093 expression predicted an unfavourable prognosis, and was associated with the lymph node metastasis, TNM staging and tumor size in ESCC tissues. Circ_0001093 knockdown suppressed cell proliferation, invasion, migration and glutamine metabolism of ESCC cells, while circ_0001093 over-expression showed the opposite effects. Mechanistically, circ_0001093 acted as a competing endogenous RNA (ceRNA) by sponging miR-579-3p, thereby increasing GLS expression. Furthermore, the inhibitory effects of circ_0001093 knockdown on the invasion, migration and glutamine metabolism were partly rescued by miR-579-3p inhibition or GLS over-expression in ESCC cells. Additionally, miR-579-3p expression was down-regulated in ESCC tissues, while GLS expression was up-regulated. In conclusion, this study first provides evidence that the circ_0001093/miR-579-3p/GLS regulatory network can affect glutamine metabolism and malignant phenotype of ESCC, which can further impact ESCC progression.