Dysregulation of the Urothelial Cancer Associated 1 Long Noncoding RNA Promotes Proliferation of Vascular Smooth Muscle Cells by Modulating Expression of P27KIP1/CDK2

Silencing of UCA1 attenuates the ox-LDL-induced injury of human umbilical vein endothelial cells via miR-873-5p/MAPK8 axis

LncRNA UCA1 plays a vital role in cardiovascular diseases. Endothelial cell dysfunction is a prerequisite for atherosclerosis (AS) development. However, the pathophysiological role of UCA1 in endothelial cell dysfunction induced by ox-LDL remains obscure. Here, we observed that UCA1 was upregulated in the sera of patients with AS and ox-LDL-treated endothelial cells. UCA1 knockdown dramatically reduced the cell apoptosis induced by ox-LDL and the production of pro-inflammatory cytokines and ROS in endothelial cells. Mechanistically, we found that UCA1 directly targeted miR-873-5p. UCA1 knockdown increased, while UCA1 overexpression decreased the expression of miR-873-5p. Further, we found that mitogen-activated protein kinase 8 (MAPK8) was a downstream target gene of miR-873-5p. MAPK8 overexpression or miR-873-5p knockdown reduced the enhancement of ox-LDL-induced cell apoptosis, oxidative stress, and pro-inflammatory cytokine production conferred by UCA1 knockdown. In conclusion, UCA1 can protect Human Umbilical Vein Endothelial Cells from ox-LDL-induced injury via the miR-873-5p/MAPK8 axis.

An Unanticipated Modulation of Cyclin-Dependent Kinase Inhibitors: The Role of Long Non-Coding RNAs

It is now definitively established that a large part of the human genome is transcribed. However, only a scarce percentage of the transcriptome (about 1.2%) consists of RNAs that are translated into proteins, while the large majority of transcripts include a variety of RNA families with different dimensions and functions. Within this heterogeneous RNA world, a significant fraction consists of sequences with a length of more than 200 bases that form the so-called long non-coding RNA family. The functions of long non-coding RNAs range from the regulation of gene transcription to the changes in DNA topology and nucleosome modification and structural organization, to paraspeckle formation and cellular organelles maturation. This review is focused on the role of long non-coding RNAs as regulators of cyclin-dependent kinase inhibitors’ (CDKIs) levels and activities. Cyclin-dependent kinases are enzymes necessary for the tuned progression of the cell division cycle. The control of their activity takes place at various levels. Among these, interaction with CDKIs is a vital mechanism. Through CDKI modulation, long non-coding RNAs implement control over cellular physiology and are associated with numerous pathologies. However, although there are robust data in the literature, the role of long non-coding RNAs in the modulation of CDKIs appears to still be underestimated, as well as their importance in cell proliferation control.

Inhibition of LOXL1-AS1 alleviates oxidative low-density lipoprotein induced angiogenesis via downregulation of miR-590-5p mediated KLF6/VEGF signaling pathway

Increasing evidences have confirmed that long non-coding RNA LOXL1-AS1 functions in multiple human diseases. Here, we aim to explore the function and mechanism of LOXL1-AS1 in modulating oxidized low-density lipoprotein (ox-LDL)-induced angiogenesis of endothelial cells (ECs). Presently, we found that LOXL1-AS1 and KLF6 were upregulated in ECs treated by Ox-LDL in a dose- and time-dependent manner while miR-590-5p was downregulated. Overexpression of LOXL1-AS1 aggravated Ox-LDL mediated ECs proliferation and migration, and promoted angiogenesis both in vitro and in vivo. On the contrary, enhancing miR-590-5p or inhibiting LOXL1-AS1 level led to suppressive effects on the proliferation, migration and angiogenesis of ECs. Moreover, LOXL1-AS1 upregulation promoted the expression of vascular endothelial growth factor (VEGF), MMPs (including MMP2, MMP9, and MMP14) and also activated VEGF/VEGFR2/PI3K/Akt/eNOS pathway. Mechanistically, LOXL1-AS1 works as a competitive endogenous RNA (ceRNA) by sponging miR-590-5p, which targeted at the 3'-untranslated region (3'UTR) of KLF6. Additionally, the proliferation, migration, and angiogenesis of ECs were elevated following KLF6 upregulation. By detecting the expression of LOXL1-AS1 and miR-590-5p in the serum of healthy donors and atherosclerosis patients, it was found that LOXL1-AS1 was upregulated in atherosclerosis patients (compared with healthy donors) and had a negative relationship with miR-590-5p. Taken together, LOXL1-AS1 promoted Ox-LDL induced angiogenesis via regulating miR-590-5p-modulated KLF6/VEGF signaling pathway. The LOXL1-AS1-miR-590-5p axis exerts a novel role in the progression of atherosclerosis.

Inhibition of LOXL1-AS1 alleviates oxidative low-density lipoprotein induced angiogenesis via downregulation of miR-590-5p mediated KLF6/VEGF signaling pathway

Increasing evidences have confirmed that long non-coding RNA LOXL1-AS1 functions in multiple human diseases. Here, we aim to explore the function and mechanism of LOXL1-AS1 in modulating oxidized low-density lipoprotein (ox-LDL)-induced angiogenesis of endothelial cells (ECs). Presently, we found that LOXL1-AS1 and KLF6 were upregulated in ECs treated by Ox-LDL in a dose- and time-dependent manner while miR-590-5p was downregulated. Overexpression of LOXL1-AS1 aggravated Ox-LDL mediated ECs proliferation and migration, and promoted angiogenesis both in vitro and in vivo. On the contrary, enhancing miR-590-5p or inhibiting LOXL1-AS1 level led to suppressive effects on the proliferation, migration and angiogenesis of ECs. Moreover, LOXL1-AS1 upregulation promoted the expression of vascular endothelial growth factor (VEGF), MMPs (including MMP2, MMP9 and MMP14) and also activated VEGF/VEGFR2/PI3K/Akt/eNOS pathway. Mechanistically, LOXL1-AS1 works as a competitive endogenous RNA (ceRNA) by sponging miR-590-5p, which targeted at the 3'-untranslated region (3'UTR) of KLF6. Additionally, the proliferation, migration and angiogenesis of ECs were elevated following KLF6 upregulation. By detecting the expression of LOXL1-AS1 and miR-590-5p in the serum of healthy donors and atherosclerosis patients, it was found that LOXL1-AS1 was upregulated in atherosclerosis patients (compared with healthy donors) and had a negative relationship with miR-590-5p. Taken together, LOXL1-AS1 promoted Ox-LDL induced angiogenesis via regulating miR-590-5p-modulated KLF6/VEGF signaling pathway. The LOXL1-AS1-miR-590-5p axis exerts a novel role in the progression of atherosclerosis.

Circular RNA circUBR4 regulates ox-LDL-induced proliferation and migration of vascular smooth muscle cells through miR-185-5p/FRS2 axis

Circular RNAs (circRNAs) have been reported to play vital roles in atherosclerosis. However, the precise roles of circUBR4 in atherosclerosis remain unclear. The purpose of this study is to investigate the regulatory roles of circUBR4 in atherosclerosis. The expression levels of circUBR4, miR-185-5p, and Fibroblast growth factor receptor substrate 2 (FRS2) were analyzed by real-time quantitative polymerase chain reaction (RT-qPCR) assay. Human vascular smooth muscle cells (VSMCs) were treated with oxidized low-density lipoprotein (ox-LDL) to mimic atherosclerosis condition in vitro. Cell proliferation was determined by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl-2H-tetrazol-3-ium bromide (MTT), colony-forming, and 5-ethynyl-2'-deoxyuridine (EdU) assays. Wound healing and transwell assays were used to assess cell migration. The interaction relationship between miR-185-5p and circUBR4 or FRS2 was confirmed by dual-luciferase reporter and RNA pull-down assays. CircUBR4 was overexpressed in atherosclerosis patients and VSMCs treated with ox-LDL, and the knockdown of circUBR4 abolished ox-LDL-induced enhanced effects on the proliferation and migration of VSMCs. MiR-185-5p, interacted with FRS2, was a target of circUBR4 in VSMCs. The silencing of miR-185-5p reversed the effects caused by circUBR4 knockdown on ox-LDL-induced VSMCs. In addition, overexpression of miR-185-5p suppressed the proliferation and migration of VSMCs by targeting FRS2. CircUBR4 contributed to ox-LDL-induced VSMC proliferation and migration through up-regulating FRS2 via miR-185-5p.

Knockdown of lncRNA ABHD11-AS1 Suppresses the Tumorigenesis of Pancreatic Cancer via Sponging miR-1231

Background

Pancreatic cancer ranks first among the most aggressive malignancies. Long non-coding RNA (LncRNA) ABHD11-AS1 is known to be upregulated in pancreatic cancer. However, the mechanism by which ABHD11-AS1 mediates the tumorigenesis of pancreatic cancer remains unclear.

Methods

Gene and protein expressions in pancreatic cancer cells were detected by qRT-PCR and Western blot, respectively. Cell viability was measured by CCK-8 assay. Cell apoptosis and cycle were tested by flow cytometry. In addition, cell migration and invasion were tested by wound healing and transwell assay, respectively. The correlation between ABHD11-AS1, miR-1231 and cyclin E1 was confirmed by dual-luciferase report and RNA pull-down. Finally, xenograft mice model was established to investigate the role of ABDH-AS1 in pancreatic cancer in vivo.

Results

ABHD11-AS1 was found to be negatively correlated with the survival rate of patients with pancreatic cancer. ABHD11-AS1 silencing significantly inhibited the proliferation and induced the apoptosis of pancreatic cancer cells. Additionally, knockdown of ABHD11-AS1 greatly inhibited the migration and invasion of pancreatic cancer cells. Meanwhile, ABHD11-AS1 bound to miR-1231 and cyclin E1 was found to be the target of miR-1231. Moreover, ABHD11-AS1 knockdown-induced G1 arrest in pancreatic cancer cells was reversed by miR-1231 antagomir. Finally, knockdown of ABHD11-AS1 obviously inhibited the tumor growth of pancreatic cancer in vivo.

Conclusion

ABHD11-AS1 silencing significantly inhibited the tumorigenesis of pancreatic cancer in vitro and in vivo. Thus, ABHD11-AS1 may serve as a potential target for the treatment of pancreatic cancer.