Long Non-Coding RNA CASC7 Promotes Proliferation and Inhibits Apoptosis of Hepatocellular Carcinoma Cells via Downregulating miR-340-5p CASC7/miR-340-5p Axis in Hepatocellular Carcinoma

Background: Hepatocellular carcinoma (HCC) is a common malignant tumor worldwide with a poor prognosis. Amounting studies revealed that long non-coding RNAs (lncRNAs) show important roles in various biological processes. The purpose of this study was to explore the biological function and potential molecular mechanism of CASC7 in HCC. Methods: CASC7 expression in HCC cell lines was detected by qRT-PCR. The expressions of CASC7 and miR-340-5p were changed by transfection of miR-340-5p mimic, the CASC7 overexpression and knockdown plasmids. The interaction between CASC7 and miR-340-5p was assessed by a Dual-Luciferase reporter assay. The biological functions of CASC7 were evaluated by CCK-8, colony formation assay, ROS assay kit, immunofluorescence and flow cytometry (FCM). Results: CASC7 was upregulated in HCC cell lines. CASC7 overexpression significantly promoted cell proliferation, as well as inhibited apoptosis and oxidative stress. In contrast, CASC7 knockdown could reverse these above changes. The result of the Dual-luciferase reporter assay revealed that CASC7 directly targeted miR-340-5p and negatively regulated its expression. In addition, CASC7 promoted proliferation and inhibited apoptosis of HCC cells through activating Nrf2 pathway by downregulating miR-340-5p. Conclusions: In summary, CASC7 promotes HCC tumorigenesis and progression through the Nrf2 pathway by targeting miR-340-5p, which may provide a new target for therapy of HCC.

Emerging Role of Exosomal Long Non-coding RNAs in Spaceflight-Associated Risks in Astronauts

During spaceflight, astronauts are exposed to multiple unique environmental factors, particularly microgravity and ionizing radiation, that can cause a range of harmful health consequences. Over the past decades, increasing evidence demonstrates that the space environment can induce changes in gene expression and RNA processing. Long non-coding RNA (lncRNA) represent an emerging area of focus in molecular biology as they modulate chromatin structure and function, the transcription of neighboring genes, and affect RNA splicing, stability, and translation. They have been implicated in cancer development and associated with diverse cardiovascular conditions and associated risk factors. However, their role on astronauts’ health after spaceflight remains poorly understood. In this perspective article, we provide new insights into the potential role of exosomal lncRNA after spaceflight. We analyzed the transcriptional profile of exosomes isolated from peripheral blood plasma of three astronauts who flew on various Shuttle missions between 1998–2001 by RNA-sequencing. Computational analysis of the transcriptome of these exosomes identified 27 differentially expressed lncRNAs with a Log2 fold change, with molecular, cellular, and clinical implications.

Long Non-coding RNA: Insight Into Mechanisms of Alzheimer's Disease

Alzheimer's disease (AD), a heterogeneous neurodegenerative disorder, is the most common cause of dementia accounting for an estimated 60–80% of cases. The pathogenesis of AD remains unclear, and no curative treatment is available so far. Increasing evidence has revealed a vital role of non-coding RNAs (ncRNAs), especially long non-coding RNAs (lncRNAs), in AD. LncRNAs contribute to the pathogenesis of AD via modulating amyloid production, Tau hyperphosphorylation, mitochondrial dysfunction, oxidative stress, synaptic impairment and neuroinflammation. This review describes the biological functions and mechanisms of lncRNAs in AD, indicating that lncRNAs may provide potential therapeutic targets for the diagnosis and treatment of AD.

High-grade ovarian cancer associated H/ACA snoRNAs promote cancer cell proliferation and survival

ABSTRACT Small nucleolar RNAs (snoRNAs) are an omnipresent class of non-coding RNAs involved in the modification and processing of ribosomal RNA (rRNA). As snoRNAs are required for ribosome production, the increase of which is a hallmark of cancer development, their expression would be expected to increase in proliferating cancer cells. However, assessing the nature and extent of snoRNAs’ contribution to cancer biology has been largely limited by difficulties in detecting highly structured RNA. In this study, we used a dedicated midsize non-coding RNA (mncRNA) sensitive sequencing technique to accurately survey the snoRNA abundance in independently verified high-grade serous ovarian carcinoma (HGSC) and serous borderline tumour (SBT) tissues. The results identified SNORA81, SNORA19 and SNORA56 as an H/ACA snoRNA signature capable of discriminating between independent sets of HGSC, SBT and normal tissues. The expression of the signature SNORA81 correlates with the level of ribosomal RNA (rRNA) modification and its knockdown inhibits 28S rRNA pseudouridylation and accumulation leading to reduced cell proliferation and migration. Together our data indicate that specific subsets of H/ACA snoRNAs may promote tumour aggressiveness by inducing rRNA modification and synthesis.

A Review on the Role of SPRY4-IT1 in the Carcinogenesis

Sprouty RTK signaling antagonist 4-intronic transcript 1 (SPRY4-IT1) is a long non-coding RNA (lncRNA) encoded by a gene located on 5q31.3. This lncRNA has a possible role in the regulation of cell growth, proliferation, and apoptosis. Moreover, since SPRY4-IT1 controls levels of lipin 2, it is also involved in the biosynthesis of lipids. During the process of biogenesis, SPRY4-IT1 is produced as a primary transcript which is then cleaved to generate a mature transcript which is localized in the cytoplasm. SPRY4-IT1 has oncogenic roles in diverse tissues. A possible route of participation of SPRY4-IT1 in the carcinogenesis is through sequestering miRNAs such as miR-101-3p, miR‐6882‐3p and miR-22-3p. The sponging effect of SPRY4-IT1 on miR-101 has been verified in colorectal cancer, osteosarcoma, cervical cancer, bladder cancer, gastric cancer and cholangiocarcinoma. SPRY4-IT1 has functional interactions with HIF-1α, NF-κB/p65, AMPK, ZEB1, MAPK and PI3K/Akt signaling. We explain the role of SPRY4-IT1 in the carcinogenesis according to evidence obtained from cell lines, xenograft models and clinical studies.