MiR-494-3p promotes PI3K/AKT pathway hyperactivation and human hepatocellular carcinoma progression by targeting PTEN

Down-expression of miR-494-3p in senescent osteocyte-derived exosomes inhibits osteogenesis and accelerates age-related bone loss via PTEN/PI3K/AKT pathway

Aims

To investigate the effects of senescent osteocytes on bone homeostasis in the progress of age-related osteoporosis and explore the underlying mechanism.

Methods

In a series of in vitro experiments, we used tert-Butyl hydroperoxide (TBHP) to induce senescence of MLO-Y4 cells successfully, and collected conditioned medium (CM) and senescent MLO-Y4 cell-derived exosomes, which were then applied to MC3T3-E1 cells, separately, to evaluate their effects on osteogenic differentiation. Furthermore, we identified differentially expressed microRNAs (miRNAs) between exosomes from senescent and normal MLO-Y4 cells by high-throughput RNA sequencing. Based on the key miRNAs that were discovered, the underlying mechanism by which senescent osteocytes regulate osteogenic differentiation was explored. Lastly, in the in vivo experiments, the effects of senescent MLO-Y4 cell-derived exosomes on age-related bone loss were evaluated in male SAMP6 mice, which excluded the effects of oestrogen, and the underlying mechanism was confirmed.

Results

The CM and exosomes collected from senescent MLO-Y4 cells inhibited osteogenic differentiation of MC3T3-E1 cells. RNA sequencing detected significantly lower expression of miR-494-3p in senescent MLO-Y4 cell-derived exosomes compared with normal exosomes. The upregulation of exosomal miR-494-3p by miRNA mimics attenuated the effects of senescent MLO-Y4 cell-derived exosomes on osteogenic differentiation. Luciferase reporter assay demonstrated that miR-494-3p targeted phosphatase and tensin homolog (PTEN), which is a negative regulator of the phosphoinositide 3-kinase (PI3K)/AKT pathway. Overexpression of PTEN or inhibition of the PI3K/AKT pathway blocked the functions of exosomal miR-494-3p. In SAMP6 mice, senescent MLO-Y4 cell-derived exosomes accelerated bone loss, which was rescued by upregulation of exosomal miR-494-3p.

Conclusion

Reduced expression of miR-494-3p in senescent osteocyte-derived exosomes inhibits osteogenic differentiation and accelerates age-related bone loss via PTEN/PI3K/AKT pathway.

Systematic computational hunting for small RNAs derived from ncRNAs during dengue virus infection in endothelial HMEC-1 cells

In recent years, a population of small RNA fragments derived from non-coding RNAs (sfd-RNAs) has gained significant interest due to its functional and structural resemblance to miRNAs, adding another level of complexity to our comprehension of small-RNA-mediated gene regulation. Despite this, scientists need more tools to test the differential expression of sfd-RNAs since the current methods to detect miRNAs may not be directly applied to them. The primary reasons are the lack of accurate small RNA and ncRNA annotation, the multi-mapping read (MMR) placement, and the multicopy nature of ncRNAs in the human genome. To solve these issues, a methodology that allows the detection of differentially expressed sfd-RNAs, including canonical miRNAs, by using an integrated copy-number-corrected ncRNA annotation was implemented. This approach was coupled with sixteen different computational strategies composed of combinations of four aligners and four normalization methods to provide a rank-order of prediction for each differentially expressed sfd-RNA. By systematically addressing the three main problems, we could detect differentially expressed miRNAs and sfd-RNAs in dengue virus-infected human dermal microvascular endothelial cells. Although more biological evaluations are required, two molecular targets of the hsa-mir-103a and hsa-mir-494 (CDK5 and PI3/AKT) appear relevant for dengue virus (DENV) infections. Here, we performed a comprehensive annotation and differential expression analysis, which can be applied in other studies addressing the role of small fragment RNA populations derived from ncRNAs in virus infection.

Serum microRNA Profiles and Pathways in Hepatitis B-Associated Hepatocellular Carcinoma: A South African Study

The incidence and mortality of hepatocellular carcinoma (HCC) in Sub-Saharan Africa is projected to increase sharply by 2040 against a backdrop of limited diagnostic and therapeutic options. Two large South African-based case control studies have developed a serum-based miRNome for Hepatitis B-associated hepatocellular carcinoma (HBV-HCC), as well as identifying their gene targets and pathways. Using a combination of RNA sequencing, differential analysis and filters including a unique molecular index count (UMI) ≥ 10 and log fold change (LFC) range > 2: <-0.5 (p < 0.05), 91 dysregulated miRNAs were characterized including 30 that were upregulated and 61 were downregulated. KEGG analysis, a literature review and other bioinformatic tools identified the targeted genes and HBV-HCC pathways of the top 10 most dysregulated miRNAs. The results, which are based on differentiating miRNA expression of cases versus controls, also develop a serum-based miRNA diagnostic panel that indicates 95.9% sensitivity, 91.0% specificity and a Youden Index of 0.869. In conclusion, the results develop a comprehensive African HBV-HCC miRNome that potentially can contribute to RNA-based diagnostic and therapeutic options.

Targeting EGFR/PI3K/AKT/mTOR Signaling in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) poses a significant global health concern, with its incidence steadily increasing. The development of HCC is a multifaceted, multi-step process involving alterations in various signaling cascades. In recent years, significant progress has been made in understanding the molecular signaling pathways that play central roles in hepatocarcinogenesis. In particular, the EGFR/PI3K/AKT/mTOR signaling pathway in HCC has garnered renewed attention from both basic and clinical researchers. Preclinical studies in vitro and in vivo have shown the effectiveness of targeting the key components of this signaling pathway in human HCC cells. Thus, targeting these signaling pathways with small molecule inhibitors holds promise as a potential therapeutic option for patients with HCC. In this review, we explore recent advancements in understanding the role of the EGFR/PI3K/AKT/mTOR signaling pathway in HCC and assess the effectiveness of targeting this signaling cascade as a potential strategy for HCC therapy based on preclinical studies.

Prenatal and Neonatal Bone Health: Updated Review on Early Identification of Newborns at High Risk for Osteopenia

Bone health starts with maternal health and nutrition, which influences bone mass and density already in utero. The mechanisms underlying the effect of the intrauterine environment on bone health are partly unknown but certainly include the 'foetal programming' of oxidative stress and endocrine systems, which influence later skeletal growth and development. With this narrative review, we describe the current evidence for identifying patients with risk factors for developing osteopenia, today's management of these populations, and screening and prevention programs based on gestational age, weight, and morbidity. Challenges for bone health prevention include the need for new technologies that are specific and applicable to pregnant women, the foetus, and, later, the newborn. Radiofrequency ultrasound spectrometry (REMS) has proven to be a useful tool in the assessment of bone mineral density (BMD) in pregnant women. Few studies have reported that transmission ultrasound can also be used to assess BMD in newborns. The advantages of this technology in the foetus and newborn are the absence of ionising radiation, ease of use, and, above all, the possibility of performing longitudinal studies from intrauterine to extrauterine life. The use of these technologies already in the intrauterine period could help prevent associated diseases, such as osteoporosis and osteopenia, which are characterised by a reduction in bone mass and degeneration of bone structure and lead to an increased risk of fractures in adulthood with considerable social repercussions for the related direct and indirect costs.

Downregulation of microRNA‑494 inhibits cell proliferation in lung squamous cell carcinoma via the induction of PUMA‑α‑mediated apoptosis

Increased evidence has shown that abnormal microRNA (miRNA) plays pivotal roles in numerous types of cancer. However, their expression, function and mechanism in lung squamous cell carcinoma (LSCC) remains to be fully elucidated. The aim of the present study was to investigate the suppressive role of miR-494 in LSCC progression and elucidate its regulatory mechanism. By analyzing expression profiles of miRNAs in LSCC tissues using miRNA microarray, it was revealed that miR-494 was significantly upregulated in 22 pairs of LSCC tissues. Subsequently, reverse transcription-quantitative PCR was performed to determine the expression of miR-494 and p53-upregulated-modulator-of-apoptosis-α (PUMA-α). Western blot analysis was conducted to examine protein levels. Dual-luciferase reporter assay was used to confirm the binding between miR-494 and PUMA-α. Annexin V-fluoresceine isothiocyanate/propidium iodide staining and CCK-8 assays were employed to determine cell apoptosis and cell viability, respectively. It was also revealed that miR-494 was highly expressed in LSCC cell lines compared with that in 16HBE cells. Further experiments confirmed that knockdown of miR-494 reduced cell viability and induced LSCC apoptosis. Bioinformatics analysis predicted that miR-494 could potentially target PUMA-α; also known as Bcl-2-binding component 3, a pro-apoptotic factor, and an inverse correlation between the expression of miR-494 and PUMA-α mRNA levels in LSCC tissues was found. Furthermore, PUMA-α inhibition could reverse the promoting effect of miR-494 knockdown on apoptosis in LSCC cells. Taken together, these findings demonstrated that miR-494 functions as an oncogene by targeting PUMA-α in LSCC, and miR-494 may serve as a novel therapeutic target for treating LSCC.

The Multifunctional Protein Syntenin-1: Regulator of Exosome Biogenesis, Cellular Function, and Tumor Progression

Syntenin acts as an adaptor and scaffold protein through its two PSD-95, Dlg, and ZO-1 (PDZ) domains, participating in multiple signaling pathways and modulating cellular physiology. It has been identified as an oncogene, promoting cancer development, metastasis, and angiogenesis in various carcinomas. Syntenin-1 is also associated with the production and release of exosomes, small extracellular vesicles that play a significant role in intercellular communication by containing bioactive molecules such as proteins, lipids, and nucleic acids. The trafficking of exosomes involves a complex interplay of various regulatory proteins, including syntenin-1, which interacts with its binding partners, syndecan and activated leukocyte cell adhesion molecule (ALIX). Exosomal transfer of microRNAs, a key cargo, can regulate the expression of various cancer-related genes, including syntenin-1. Targeting the mechanism involving the regulation of exosomes by syntenin-1 and microRNAs may provide a novel treatment strategy for cancer. This review highlights the current understanding of syntenin-1's role in regulating exosome trafficking and its associated cellular signaling pathways.

Extracellular vesicles: an emerging player in retinal homeostasis

Extracellular vesicles (EVs) encompass secreted membrane vesicles of varied sizes, including exosomes (-30-200 nm) and microvesicles (MVs) that are ∼100-1,000 nm in size. EVs play an important role in autocrine, paracrine, and endocrine signaling and are implicated in myriad human disorders including prominent retinal degenerative diseases, like age related macular degeneration (AMD) and diabetic retinopathy (DR). Studies of EVs in vitro using transformed cell lines, primary cultures, and more recently, induced pluripotent stem cell derived retinal cell type(s) (e.g., retinal pigment epithelium) have provided insights into the composition and function of EVs in the retina. Furthermore, consistent with a causal role of EVs in retinal degenerative diseases, altering EV composition has promoted pro-retinopathy cellular and molecular events in both in vitro and in vivo models. In this review, we summarize the current understanding of the role of EVs in retinal (patho)physiology. Specifically, we will focus on disease-associated EV alterations in specific retinal diseases. Furthermore, we discuss the potential utility of EVs in diagnostic and therapeutic strategies for targeting retinal diseases.

Cardiomyocyte-specific Peli1 contributes to the pressure overload-induced cardiac fibrosis through miR-494-3p-dependent exosomal communication

Cardiac fibrosis is an essential pathological process in pressure overload (PO)-induced heart failure. Recently, myocyte-fibroblast communication is proven to be critical in heart failure, in which, pathological growth of cardiomyocytes (CMs) may promote fibrosis via miRNAs-containing exosomes (Exos). Peli1 regulates the activation of NF-κB and AP-1, which has been demonstrated to engage in miRNA transcription in cardiomyocytes. Therefore, we hypothesized that Peli1 in CMs regulates the activation of cardiac fibroblasts (CFs) through an exosomal miRNA-mediated paracrine mechanism, thereby promoting cardiac fibrosis. We found that CM-conditional deletion of Peli1 improved PO-induced cardiac fibrosis. Moreover, Exos from mechanical stretch (MS)-induced WT CMs (WT MS-Exos) promote activation of CFs, Peli1^-/- MS-Exos reversed it. Furthermore, miRNA microarray and qPCR analysis showed that miR-494-3p was increased in WT MS-Exos while being down regulated in Peli1^-/- MS-Exos. Mechanistically, Peli1 promoted miR-494-3p expression via NF-κB/AP-1 in CMs, and then miR-494-3p induced CFs activation by inhibiting PTEN and amplifying the phosphorylation of AKT, SMAD2/3, and ERK. Collectively, our study suggests that CMs Peli1 contributes to myocardial fibrosis via CMs-derived miR-494-3p-enriched exosomes under PO, and provides a potential exosomal miRNA-based therapy for cardiac fibrosis.

LncRNA LINC00534 regulates cell proliferation and migration via the miR-494-3p/PTEN axis in HTR-8/SVneo cells

BACKGROUND

LncRNA LINC00534 has been found to be differentially expressed in placental tissue samples of preeclampsia (PE), but the exact mechanism is still unclear.

METHODS

In vitro assays were carried out in HTR-8/SVneo cells using various methods, including cell counting kit-8 (CCK-8), transwells, flow cytometry, and Western blotting (WB) and quantitative polymerase chain reaction. RNA pull-down and bioinformatics analysis were applied to examine other potential underlying mechanisms involved.

RESULTS

We found that there was a high expression of LINC00534 in the placental tissues of patients with PE. LINC00534 overexpression (OE) significantly inhibited cell proliferation and migration as well as accelerated cell apoptosis in HTR8/SVneo cells. The knockdown of LINC00534 produced an opposite trend. Mechanistically, LINC00534 promoted the expressions of PTEN (Phosphatase and tensin homolog) through decreasing miR-494-3p. Further rescue studies showed that LINC00534 played a role by targeting mir-494-3p, which controlled the growth and migration of HTR-8/SVneo trophoblast cells via regulating PTEN/PI3K/AKT (Phosphatidylinositol3-kinase/protein kinase B). Moreover, lncRNA pull-down assay identified 198 potential bound proteins for LINC00534. Those proteins were mostly involved in RNA processing and modification, posttranslational modification, protein turnover, and chaperones.

CONCLUSION

Overall, by suppressing HTR8/SVneo cell growth and migration via the miR-494-3p/PTEN axis and other mechanisms, LINC00534 offers new insight into PE pathogenesis.

Extracellular Polysaccharide from Rhizopus nigricans Inhibits Hepatocellular Carcinoma via miR-494-3p/TRIM36 Axis and Cyclin E Ubiquitination

BACKGROUND AND AIMS

This study was designed to uncover the mechanism for extracellular polysaccharide (EPS1-1)-mediated effects on hepatocellular carcinoma (HCC) development.

METHODS

HCC cells were treated with EPS1-1, miR-494-3p mimic, sh-TRIM36, and pcDNA3.1-TRIM36. The levels of miR-494-3p and TRIM36 were measured in normal hepatocytes, THLE-2, and HepG2 and HuH7HCC cell lines, along with the protein expression of cyclin D/E and p21. The proliferation, cell cycle, and apoptosis of HCC cells were assayed. The interactions between miR-494-3p and TRIM36, and between TRIM36 and cyclin E were assessed. Finally, the expression and localization of TRIM36 and cyclin E were monitored, and tumor apoptosis was detected, in tumor xenograft model.

RESULTS

EPS1-1 suppressed HCC cell proliferation and cyclin D/E expression and promoted apoptosis and p21 expression. miR-494-3p was upregulated and TRIM36 was downregulated in HCC cells. Transfection with miR-494-3p mimic or sh-TRIM36 facilitated HCC cell proliferation and the expression of cyclin D/E protein but they inhibited apoptosis and p21 expression in the presence of EPS1-1. Overexpression of TRIM36 further consolidated EPS1-1-mediated inhibition of HCC proliferation, cyclin D/E, and the promotion of apoptosis and p21 expression. Those effects were reversed by miR-494-3p overexpression. TRIM36 was a target gene of miR-494-3p, and TRIM36 induced cyclin E ubiquitination. EPS1-1 suppressed cyclin E expression, promoted TRIM36 expression and tumor apoptosis, all of which were abrogated by increasing the expression of miR-494-3p in vivo.

CONCLUSIONS

EPS1-1 protected against HCC by limiting its proliferation and survival through the miR-494-3p/TRIM36 axis and by inducing cyclin E ubiquitination.

Six MicroRNA Prognostic Models for Overall Survival of Lung Adenocarcinoma

Objective

The purpose of this study is to screen for microRNAs (miRNAs) associated with the prognosis of lung adenocarcinoma (LUAD) and to explore its prognosis and effects on the tumor microenvironment in patients with LUAD.

Methods

Gene expression data, miRNA expression data, and clinical data for two different databases, TCGA-LUAD and CPTAC-3 LUAD, were downloaded from the GDC database. The miRNA prognosis of LUAD was filtered by the Cox proportional hazard model and the Least Absolute Shrinkage and Selection Operator (LASSO) regression model. The performance of the model was validated by time-dependent receiver operating characteristics (ROC) curves. Possible biological processes associated with the miRNAs target gene were analyzed through Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG). Finally, the prognostic model was scored by risk, divided into high- and low-risk groups by median, and the differences in the immersion level of 21 immune cells in the high- and low-risk groups were assessed. To gain a deeper understanding of the underlying mechanism behind the model, the two most important miRNAs in the model, miR-195-3p and miR-5571-5p, were selected for HPA database validation and ceRNA network construction.

Results

Of the 209 variance expressions identified in the screening analysis, 145 were upregulated and 64 were downregulated by miRNAs. The prognostic models of six miRNA genes were obtained: miR-195-3p, miR-5571-5p, miR-584-3p, miR-494-3p, miR-4664-3p, and miR-1293. These six genes were significantly associated with survival rates in LUAD patients. In particular, miR-1293, miR-195-3p, and miR-5571-5p are highly correlated with OS. The higher expression of miR-195-3p and miR-5571-5p, the better survival of LUAD OS is, and these two miRNA expressions contribute the most to the model. Finally, after sorting the risk scores calculated from low to high using the prognostic model, the patients with higher scores had shorter survival time and higher frequency of death, and there were significant differences in the immersion levels of 21 immune cells in the high- and low-risk groups. ceRNA network analysis found that TM9SF3 was regulated by miR-195-3p and was highly expressed in the tissues of LUAD patients, and the prognosis of the patients was poor.

Conclusions

miR-195-3p, miR-5571-5p, miR-584-3p, miR-494-3p, miR-4664-3p, and miR-1293 may be used as new biomarkers for prognosis prediction of LUAD. Our results also identified a lncRNA MEG3/miR-195-3p/RAB1A/TM9SF3 regulatory axis, which may also play an important role in the progression of LUAD. Further study needs to be conducted to verify this result.

miR-494-3p Promotes Erastin-Induced Ferroptosis by Targeting REST to Activate the Interplay between SP1 and ACSL4 in Parkinson’s Disease

Background

Ferroptosis is a type of iron-dependent programmed cell death. Ferroptosis has been shown to be a significant factor for the pathogenesis of Parkinson's disease (PD). However, the mechanism involved in ferroptosis has not been fully elucidated in PD.

Methods

Repressor element-1 silencing transcription factor (REST) and specificity protein 1 (SP1) expressions were monitored by qRT-PCR. Cell viability, reactive oxygen species (ROS), and mitochondrial injury were validated by CCK-8, flow cytometry, and transmission electron microscope. The levels of neurons-related proteins and ferroptosis-associated proteins were identified by western blot and immunofluorescence assays. The interaction between miR-494-3p and REST or SP1 and ACSL4 was analyzed by luciferase, chromatin immunoprecipitation, or EMSA assay.

Results

Erastin could dose-dependently induce neuron injury and ferroptosis of LUHMES cells. miR-494-3p overexpression induced ROS production, mitochondrial damage, ferroptosis, and neuron injury in erastin-induced LUHMES cells. Likewise, miR-494-3p inhibition had the opposite effects. We also showed that REST was a target gene of miR-494-3p and could repress erastin-induced ferroptosis, neuron injury, ROS, and mitochondrial injury via SP1 in LUHMES cells. Moreover, we demonstrated that SP1 could interact with ACSL4. We also confirmed that miR-494-3p could aggravate the pathological changes of substantia nigra and corpus striatum in the MPTP-induced PD mouse model.

Conclusion

miR-494-3p significantly promotes ferroptosis by regulating the REST/SP1/ACSL4 axis in PD. Thus, our results open potential therapeutic targets for PD.

Biomarkers and Genetic Markers of Hepatocellular Carcinoma and Cholangiocarcinoma-What Do We Already Know

Simple Summary

Hepatocellular carcinoma and cholangiocarcinoma continue to remain a serious threat. In this review, we describe the most common biomarkers and genetic markers currently used in the diagnosis of hepatocellular carcinoma and cholangiocarcinoma. It can be observed that biomarkers and genetic markers might be applied in various parts of diagnosis including screening tests in a high-risk group, non-invasive detection, control of therapy, treatment selection, and control of recurrence. Also, it can be seen that nowadays there is a need for more specific markers that would improve the detection in early or very early stages of both types of cancers and further research should be focused on it.

Abstract

Hepatocellular carcinoma (HCC) is the most common primary liver cancer with an increasing worldwide mortality rate. Cholangiocarcinoma (CCA) is the second most common primary liver cancer. In both types of cancers, early detection is very important. Biomarkers are a relevant part of diagnosis, enabling non-invasive detection and control of cancer recurrence, as well as in the application of screening tests in high-risk groups. Furthermore, some of these biomarkers are useful in controlling therapy and treatment selection. Detection of some markers presents higher sensitivity and specificity in combination with other markers when compared with a single detection. Some gene aberrations are also prognostic markers in the two types of cancers. In the following review, we discuss the most common biomarkers and genetic markers currently being used in the diagnosis of hepatocellular carcinoma and cholangiocarcinoma.

Syntenin-1-mediated small extracellular vesicles promotes cell growth, migration, and angiogenesis by increasing onco-miRNAs secretion in lung cancer cells

Small extracellular vesicles (sEVs) play a pivotal role in tumor progression by mediating intercellular communication in the tumor microenvironment (TME). Syntenin-1 induces malignant tumor progression in various types of human cancers, including human lung cancer and regulates biogenesis of sEVs. However, the function of syntenin-1-regulated sEVs and miRNAs in sEVs remains to be elucidated. In the present study, we aimed to demonstrate the role of oncogenic Ras/syntenin-1 axis in the release of sEVs and elucidate the function of syntenin-1-mediated miRNAs in sEVs in lung cancer progression. The results revealed that oncogenic Ras promoted the release of sEVs by inducing syntenin-1 expression; disruption of syntenin-1 expression impaired the release of sEVs as well as sEV-mediated cancer cell migration and angiogenesis. Moreover, we identified three miRNAs, namely miR-181a, miR-425-5p, and miR-494-3p, as onco-miRNAs loaded into syntenin-1-dependent sEVs. Remarkably, miR-494-3p was highly abundant in sEVs and its release was triggered by syntenin-1 expression and oncogenic Ras. Ectopic expression of the miR-494-3p mimic enhanced the migration and proliferation of lung cancer cells as well as tube formation in endothelial cells; however, the miR-494-3p inhibitor blocked sEV-mediated effects by targeting tyrosine-protein phosphatase nonreceptor type 12 (PTPN12), a tumor suppressor. sEVs promoted tumor growth and angiogenesis by downregulating PTPN12 expression; however, the miR-494-3p inhibitor significantly suppressed these effects in vivo, confirming that miR-494-3p acts as a major onco-miRNA loaded into lung cancer cell-derived sEVs. Eventually, the oncogenic Ras/syntenin-1 axis may induce cancer progression by increasing miR-494-3p loading into sEVs in lung cancer cells in the TME.

Antitumor Effect of Regorafenib on MicroRNA Expression in Hepatocellular Carcinoma Cell Lines

Hepatocellular carcinoma (HCC) is the most common primary malignancy of the liver and is one of the leading causes of cancer-related deaths worldwide. Regorafenib, a multi-kinase inhibitor, is used as a second-line treatment for advanced HCC. Here, we aimed to investigate the mechanism of the antitumor effect of regorafenib on HCC and evaluate altered microRNA (miRNA) expression. Cell proliferation was examined in six HCC cell lines (HuH-7, HepG2, HLF, PLC/PRF/5, Hep3B, and Li-7) using the Cell Counting Kit-8 assay. Xenografted mouse models were used to assess the effects of regorafenib in vivo. Cell cycle analysis, western blotting analysis, and miRNA expression analysis were performed to identify the antitumor inhibitory potential of regorafenib on HCC cells. Regorafenib suppressed proliferation in HuH-7 cell and induced G0/G1 cell cycle arrest and cyclin D1 downregulation in regorafenib-sensitive cells. During miRNA analysis, miRNA molecules associated with the antitumor effect of regorafenib were found. Regorafenib suppresses cell proliferation and tumor growth in HCC by decreasing cyclin D1 via alterations in intracellular and exosomal miRNAs in HCC.

Golgi phosphoprotein 3 promotes angiogenesis and sorafenib resistance in hepatocellular carcinoma via upregulating exosomal miR-494-3p

Background

Golgi phosphoprotein 3 (GOLPH3) has been frequently reported as an oncoprotein in a variety of tumors. However, its role in the cancer-associated intercellular signaling communication has not yet been explored. This study aimed at exploring whether GOLPH3 regulates angiogenesis and sorafenib resistance via exosomal mechanisms in hepatocellular carcinoma (HCC).

Methods

In vivo assays were performed to elucidate the function of GOLPH3 in HCC. Exosomes of HCC cells were isolated by differential centrifugation, and then measured and quantified using nanoparticle tracking analysis (NTA), BCA assay, western blot (WB), and transmission electron microscopy (TEM). Differentially expressed miRNAs in exosome were analyzed and verified through small RNA sequencing (sRNA-seq) and reverse-transcription polymerase chain reaction (RT-PCR). In addition, a series of in vitro assays were performed to determine the function of exosomes and miR-494-3p in HCC. The candidate target gene of miR-494-3p was identified by bioinformatics prediction and dual-luciferase reporter assay.

Results

Downregulation of GOLPH3 expression could suppress angiogenesis and enhance sorafenib sensitivity in HCC. Exosomes derived from GOLPH3 overexpression HCC cells promoted the angiogenesis ability of HUVECs and induced sorafenib resistance in HCC cells. A total of 13 differentially expressed miRNAs between negative control and GOLPH3 knockdown group were found in exosomes. However, GOLPH3 was only associated with miR-494-3p expression level in exosomes derived from HCC cells without affecting total cellular miR-494-3p content. Results confirmed that exosomal miR-494-3p promotes angiogenesis of HUVECs and sorafenib resistance in HCC cells through directly targeting PTEN.

Conclusions

HCC cells with high expression levels of GOLPH3 could promote angiogenesis and sorafenib resistance by enhancing exosomal miR-494-3p secretion to recipient HUVECs and HCC cells, respectively.

MicroRNA-494-3p prevents liver fibrosis and attenuates hepatic stellate cell activation by inhibiting proliferation and inducing apoptosis through targeting TRAF3

INTRODUCTION AND OBJECTIVES

Alcoholic hepatitis (AH) is characterized by high morbidity and mortality. MicroRNA-494-3p is possibly involved in the regulation of cancers, but its role in AH has been rarely studied.

MATERIALS AND METHODS

AH mice model and primarily cultured mice hepatic stellate cells (HSCs) model were constructed. Levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were analyzed by ELISA. Expressions of miRNAs, HSC activation-related proteins and fibrosis-related protein were analyzed by qRT-PCR and Western blot. Cell counting kit, colony formation and flow cytometry assays were used to detect cell viability, proliferation and apoptosis, respectively. The relationship between TNF receptor-associated factor 3 (TRAF3) and miR-494-3p was predicted and verified by TargetScan and dual-luciferase assay, respectively. Results of the above experiments were verified by rescue experiments using TRAF3.

RESULTS

Liver damage and miRNA expression were observed in AH mice, and AST and ALT levels were increased in serum of AH mice. MiR-494-3p was reduced in AH liver tissues, and it decreased the levels of α-SMA and fibrosis-related proteins. HSCs were isolated, and activating HSCs or upregulating miR-494-3p had a regulatory effect on the levels of miR-494-3p, HSC activation-related proteins and fibrosis-related proteins as well as cell viability, proliferation and apoptosis. In addition, miR-494-3p targeted TRAF3 and inhibited TRAF3 expression, while overexpressed TRAF3 promoted TRAF3 expression and rescued the regulatory effect of miR-494-3p on the levels of related proteins as well as cell viability, proliferation and apoptosis.

CONCLUSIONS

This study provided a novel mechanistic comprehension of the anti-fibrotic effect of miR-494-3p.

Specific miRNAs Change After 3 Months of GH treatment and Contribute to Explain the Growth Response After 12 Months

CONTEXT

There is growing evidence of the role of epigenetic regulation of growth, and miRNAs potentially play a role.

OBJECTIVE

The aim of this study is to identify changes in circulating miRNAs following GH treatment in subjects with isolated idiopathic GH deficiency (IIGHD) after the first 3 months of treatment, and verify whether these early changes can predict growth response.

DESIGN AND METHODS

The expression profiles of 384 miRNAs were analyzed in serum in 10 prepubertal patients with IIGHD (5 M, 5 F) at two time points before starting GH treatment (t-3, t0), and at 3 months on treatment (t+3). MiRNAs with a fold change (FC) >+1.5 or <-1.5 at t+3 were considered as differentially expressed. In silico analysis of target genes and pathways led to a validation step on 8 miRNAs in 25 patients. Clinical and biochemical parameters were collected at baseline, and at 6 and 12 months. Simple linear regression analysis and multiple stepwise linear regression models were used to explain the growth response.

RESULTS

Sixteen miRNAs were upregulated and 2 were downregulated at t+3 months. MiR-199a-5p (p = 0.020), miR-335-5p (p = 0.001), and miR-494-3p (p = 0.026) were confirmed to be upregulated at t+3. Changes were independent of GH peak values at testing, and levels stabilized after 12 months. The predicted growth response at 12 months was considerably improved compared with models using the common clinical and biochemical parameters.

CONCLUSIONS

MiR-199a-5p, miR-335-5p, and miR-494-3p changed after 3 months of GH treatment and likely reflected both the degree of GH deficiency and the sensitivity to treatment. Furthermore, they were of considerable importance to predict growth response.

Circ_0000745 promotes acute lymphoblastic leukemia progression through mediating miR-494-3p/NET1 axis

BACKGROUND

Circular RNAs (circRNAs) have shown important regulatory roles in tumorigenesis. However, the role and working mechanism of circ_0000745 in acute lymphoblastic leukemia (ALL) development remain largely unclear.

METHODS

The expression of circ_0000745, sperm antigen with calponin homology and coiled-coil domains 1 (SPECC1), microRNA-494-3p (miR-494-3p), and neuroepithelial cell transforming 1 (NET1) messenger RNA (mRNA) and protein was analyzed by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and Western blot assay. Flow cytometry was performed to assess cell apoptosis and cell cycle progression. Extracellular acidification rate (ECAR) was assessed to analyze cell glycolysis. Cell viability was analyzed by 3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide (MTT) assay. Ferroptosis was assessed through measuring the intracellular levels of iron and lipid reactive oxygen species (ROS). Dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay were conducted to validate the interaction between miR-494-3p and circ_0000745 or NET1.

RESULTS

Circ_0000745 expression was elevated in ALL patients and cell lines. Circ_0000745 knockdown restrained cell cycle progression and glycolysis and triggered cell apoptosis and ferroptosis. Circ_0000745 acted as a molecular sponge for miR-494-3p in ALL cells. miR-494-3p silencing partly diminished circ_0000745 knockdown-induced anti-tumor effects in ALL cells. NET1 was a target of miR-494-3p, and miR-494-3p overexpression-induced anti-tumor influences were partly counteracted by the accumulation of NET1 in ALL cells. Circ_0000745 can positively regulate NET1 expression by sponging miR-494-3p in ALL cells.

CONCLUSION

Circ_0000745 contributed to ALL development partly by binding to miR-494-3p to induce NET1 expression.0020.

miRNA-425-5p enhances diffuse large B cell lymphoma growth by targeting PTEN

BACKGROUND

At present, cancer is one of the greatest threats to mankind, and is associated with the highest rates of morbidity and comorbidity. Recently, the advancements in molecular biology have led to an in-depth understanding of the underlying pathophysiology, which may further impact the lead time in the context of early discovery and effective therapy of cancer. Therefore, the present study proposes a better understanding of the role of micro(miR)-425-5p in diffuse large B-cell lymphoma (DLBC).

METHODS

qRT-PCR was carried out to detect the relevant proteins, miRNA and mRNA RNA gene expression in DLBC cells. The effect of miR-425-5p on DLBC growth was examined by CCK-8 and colony formation assays. The binding relationship between genes was verified by dual-luciferase reporter gene assay.

RESULTS

We demonstrated how the over-expression of miR-425-5p can lead to increased progression of DLBC by increasing the cellular proliferation rate and colony-forming ability. Additionally, we also found that the expression of miR-425-5p could be significantly inhibited on the basis of phosphatase and tensin homolog (PTEN) signaling pathways.

CONCLUSIONS

The present study concludes that miR-425-5p is responsible for the oncogenic progression and relapse of DLBC tumorigenesis via PTEN/PI3K signaling, which can thus be effectively used to achieve better therapeutic outcomes.

Transthyretin Suppressed Tumor Progression in Nonsmall Cell Lung Cancer by Inactivating MAPK/ERK Pathway

Background: Lung malignancy is a main source of disease passing all throughout the planet, whereas the transthyretin (TTR) is a specific biomarker for clinical diagnosis. However, its role in lung malignancy stays to be obscure. Materials and Methods: In the current examination, the authors made an endeavor to research impact of abnormal expression of TTR on nonsmall cell lung carcinoma (NSCLC) by overexpression or knockdown of TTR. To further explore the instruments' fundamental mechanism part of TTR in NSCLC, several signal pathways were searched and verified. To confirm the effect of TTR overexpression on tumors, in vivo experiments were conducted. Result: It was found that upregulated TTR clearly stifled cell proliferation, migration, invasion, and expanded apoptosis. Significant suppression of phosphor-extracellular signal-regulated kinase (ERK) was observed in TTR-treated NSCLC cells, implying that TTR was important for cellular progress by regulating mitogen-activated protein kinase/ERK signaling pathway. In in vivo experiment, overexpression of TTR promoted cell apoptosis and inhibited tumor growth. Conclusion: Overall, the results suggest that TTR has a potential antitumor effect in human NSCLC progression, which provides theoretical basis for the diagnosis and treatment of NSCLC. Above all, further understanding of TTR was useful for clinical care. Clinical Trial Registration Number: 2016-08.

MiRNA-494-3p Regulates Bupivacaine-Induced Neurotoxicity by the CDK6-PI3K/AKT Signaling

Bupivacaine (BUP) is a long-acting amide local anesthetic that may induce strong neurotoxicity and neurological complications. In this study, we elucidate the influence of microRNA-494-3p (miR-494-3p) in BUP-induced neurotoxicity in primary mouse hippocampal neuronal cells. In this study, primary hippocampal neurons were isolated from neonatal C57BL/6 mice. The isolated neurons were treated with various doses of BUP. MTT assay was conducted to analyze neuronal viability. Gene expression measurement was done by RT-qPCR. The impact of miR-494-3p in BUP-mediated neural injury was examined using TUNEL, flow cytometry, western blotting, and ROS activity detection. The regulatory relationship between miR-494-3p and cyclin-dependent kinases 4 and 6 (CDK6) was identified using a luciferase reporter assay. BUP treatment led to neurotoxicity and miR-494-3p upregulation in primary cultured hippocampal neurons. Functionally, miR-494-3p depletion alleviated neuronal apoptosis and oxidative damage induced by BUP. We verified that miR-494-3p targeted and negatively modulated CDK6. MiR-494-3p depletion also activated PI3K/AKT signaling by elevating CDK6 expression in BUP-treated neurons. Furthermore, CDK6 knockdown or PI3K/AKT inactivation attenuated the neuroprotective role of miR-494-3p depletion. Silencing miR-494-3p exerts neuroprotective function in hippocampal neuronal cells against BUP-induced injury by the CDK6-PI3K/AKT pathway.

Bioinformatics Analysis Predicts hsa_circ_0026337/miR-197-3p as a Potential Oncogenic ceRNA Network for Non-small Cell Lung Cancers

BACKGROUND

Circular RNAs (circRNAs) play an essential role in developing tumors, but their role in non-small cell lung cancer (NSCLC) is unclear. Thus, the present study explored the possible molecular mechanism of circRNAs in NSCLC.

METHODS

Three circular RNA (circRNA) microarray datasets were downloaded from the Gene Expression Omnibus (GEO) database. Differential expressions of circRNAs (DECs) were identified in NSCLC tissue and compared to adjacent healthy tissue. The online cancer-specific circRNA database (CSCD) was used for the analysis of the DECs function. Protein-protein interaction (PPI) network, Kyoto Encyclopedia of Genes and Genomes (KEGG), Gene Ontology (GO), Cytoscape, and UALCAN were used to predict the critical nodes and perform patient survival analysis, respectively. The interaction between the DECs, the predicted miRNAs, and hub genes was also determined. Finally, the circRNA-miRNA-mRNA network was established.

RESULTS

The expression of hsa_circ_0049271, hsa_circ_0026337, hsa_circ_0043256, and hsa_circ_0008234 was decreased in NSCLC tissues. The Encyclopedia of RNA Interactomes (ENCORI) and CSCD database results showed that hsa_circ_0026337 was found to sponge with miR-1193, miR-197-3p, miR-3605-5p, miR-433-3p, and miR-652-3p, and hsa_circ_0043256 to sponge with miR-1252-5p, miR-494-3p, and miR-558, respectively. Subsequently, 100 mRNAs were predicted to bind with these seven miRNA response elements (MREs). The GO analysis and KEGG pathway revealed that these 100 MREs might be involved in "histone deacetylase binding" and "cellular senescence". PPI network and Cytoscape identified the top ten hub genes. Survival analysis data showed that the low expression of hsa_circ_0026337 was significantly associated with shortened survival time in NSCLC (P=0.037), which increased the expression level of hsa-miR-197-3p, thereby inhibiting the translation of specific proteins.

CONCLUSION

This study examined the circRNA-miRNA-mRNA regulatory network associated with NSCLC and explored the potential functions of DECs in the network to elucidate the mechanisms underlying disease progression in NSCLC.

Attacking the PI3K/Akt/mTOR signaling pathway for targeted therapeutic treatment in human cancer

Cancer is the second leading cause of human death globally. PI3K/Akt/mTOR signaling is one of the most frequently dysregulated signaling pathways observed in cancer patients that plays crucial roles in promoting tumor initiation, progression and therapy responses. This is largely due to that PI3K/Akt/mTOR signaling is indispensable for many cellular biological processes, including cell growth, metastasis, survival, metabolism, and others. As such, small molecule inhibitors targeting major kinase components of the PI3K/Akt/mTOR signaling pathway have drawn extensive attention and been developed and evaluated in preclinical models and clinical trials. Targeting a single kinase component within this signaling usually causes growth arrest rather than apoptosis associated with toxicity-induced adverse effects in patients. Combination therapies including PI3K/Akt/mTOR inhibitors show improved patient response and clinical outcome, albeit developed resistance has been reported. In this review, we focus on revealing the mechanisms leading to the hyperactivation of PI3K/Akt/mTOR signaling in cancer and summarizing efforts for developing PI3K/Akt/mTOR inhibitors as either mono-therapy or combination therapy in different cancer settings. We hope that this review will facilitate further understanding of the regulatory mechanisms governing dysregulation of PI3K/Akt/mTOR oncogenic signaling in cancer and provide insights into possible future directions for targeted therapeutic regimen for cancer treatment, by developing new agents, drug delivery systems, or combination regimen to target the PI3K/Akt/mTOR signaling pathway. This information will also provide effective patient stratification strategy to improve the patient response and clinical outcome for cancer patients with deregulated PI3K/Akt/mTOR signaling.

Epigenetic Contribution and Genomic Imprinting Dlk1-Dio3 miRNAs in Systemic Lupus Erythematosus

Systemic lupus erythematosus (SLE) is a multifactorial autoimmune disease that afflicts multiple organs, especially kidneys and joints. In addition to genetic predisposition, it is now evident that DNA methylation and microRNAs (miRNAs), the two major epigenetic modifications, are critically involved in the pathogenesis of SLE. DNA methylation regulates promoter accessibility and gene expression at the transcriptional level by adding a methyl group to 5' cytosine within a CpG dinucleotide. Extensive evidence now supports the importance of DNA hypomethylation in SLE etiology. miRNAs are small, non-protein coding RNAs that play a critical role in the regulation of genome expression. Various studies have identified the signature lupus-related miRNAs and their functional contribution to lupus incidence and progression. In this review, the mutual interaction between DNA methylation and miRNAs regulation in SLE is discussed. Some lupus-associated miRNAs regulate DNA methylation status by targeting the DNA methylation enzymes or methylation pathway-related proteins. On the other hand, DNA hyper- and hypo-methylation are linked with dysregulated miRNAs expression in lupus. Further, we specifically discuss the genetic imprinting Dlk1-Dio3 miRNAs that are subjected to DNA methylation regulation and are dysregulated in several autoimmune diseases, including SLE.

Integrated Genomic and Transcriptomic Analysis reveals key genes for predicting dual-phenotype Hepatocellular Carcinoma Prognosis

Dual-phenotype hepatocellular carcinoma (DPHCC) expresses both hepatocyte and cholangiocyte markers, and is characterized by high recurrence and low survival rates. The underlying molecular mechanisms of DPHCC pathogenesis are unclear.

We performed whole exome sequencing and RNA sequencing of three subtypes of HCC (10 DPHCC, 10 CK19-positive HCC, and 14 CK19-negative HCC), followed by integrated bioinformatics analysis, including somatic mutation analysis, mutation signal analysis, differential gene expression analysis, and pathway enrichment analysis. Cox proportional hazard regression analyses were applied for exploring survival related characteristics.

We found that mutated genes in DPHCC patients were associated with carcinogenesis and immunity, and the up-regulated genes were mainly enriched in transcription-related and cancer-related pathways, and the down-regulated genes were mainly enriched in immune-related pathways. CXCL9 was selected as the hub gene, which is associated with immune cells and survival prognosis. Our results showed that low CXCL9 expression was significantly associated with poor prognosis, and its expression was significantly reduced in DPHCC samples.

In conclusion, we explored the molecular mechanisms governing DPHCC development and progression and identified CXCL9, which influences the immune microenvironment and prognosis of DPHCC and might be new clinically significant biomarkers for predicting prognosis.

Noncoding RNAs Associated with Therapeutic Resistance in Pancreatic Cancer

Therapeutic resistance is an inevitable impediment towards effective cancer therapies. Evidence accumulated has shown that the signaling pathways and related factors are fundamentally responsible for therapeutic resistance via regulating diverse cellular events, such as epithelial-to-mesenchymal transition (EMT), stemness, cell survival/apoptosis, autophagy, etcetera. Noncoding RNAs (ncRNAs) have been identified as essential cellular components in gene regulation. The expression of ncRNAs is altered in cancer, and dysregulated ncRNAs participate in gene regulatory networks in pathological contexts. An in-depth understanding of molecular mechanisms underlying the modulation of therapeutic resistance is required to refine therapeutic benefits. This review presents an overview of the recent evidence concerning the role of human ncRNAs in therapeutic resistance, together with the feasibility of ncRNAs as therapeutic targets in pancreatic cancer.

Effects of propofol on cardiac function and miR-494 expression in rats with hepatic ischemia/reperfusion injury

OBJECTIVE

This study aimed to investigate the effects of propofol on cardiac function and miR-494 expression in rats with hepatic ischemia/reperfusion (I/R) injury.

METHODS

Forty healthy adult male Sprague-Dawley rats were allocated to the sham operation group and three hepatic I/R injury groups. The I/R injury groups included I/R injury only (I/R group), treatment with propofol (propofol group), and treatment with propofol + overexpressed miR-494 (propofol+miR-494 group). Apoptosis of myocardial cells and changes in cardiac function indices, including left ventricular end-diastolic diameter, left ventricular end-systolic diameter, and left ventricular posterior wall thickness, as well as changes in miR-494, were monitored.

RESULTS

The apoptotic rate of myocardial cells in the I/R group was higher, cardiac function was deteriorated, and miR-494 levels were elevated compared with the sham group. The apoptotic rate was lower, cardiac function was improved, and miR-494 levels were suppressed in the propofol group compared with the I/R group. The apoptotic rate was higher, cardiac function was deteriorated, and miR-494 levels were elevated in the propofol+miR-494 group compared with the propofol group.

CONCLUSION

Propofol plays a vital role in preventing myocardial cell apoptosis and improvement of cardiac function by suppressing miR-494 in a hepatic I/R injury rat model.

LncRNA WT1-AS/miR-494-3p Regulates Cell Proliferation, Apoptosis, Migration and Invasion via PTEN/PI3K/AKT Signaling Pathway in Non-Small Cell Lung Cancer

Background

Non-small cell lung cancer (NSCLC) is one of the most common malignancies with the highest morbidity and mortality worldwide. Long non-coding RNAs (lncRNAs) are recently recognized as noteworthy regulators of different tumors, counting NSCLC. However, the biological functions and regulatory mechanism of lncRNA WT1-AS in NSCLC progression still stay uninvestigated.

Methods

WT1-AS and miR-494-3p levels in NSCLC cell lines were detected by real-time quantitative polymerase chain reaction (RT-qPCR). In the current study, the regulatory effects of WT1-AS/miR-494-3p axis on cellular behaviors of NSCLC cell lines (A549 and NCI-H1975) were evaluated by a variety of methods. Cell counting kit-8 (CCK-8) and EDU assays were adopted to assess NSCLC cell proliferation. Tunnel staining and flow cytometry assay were applied to determine cell apoptosis and cell cycle distribution. Besides, cell migration and invasion abilities were analyzed by performing wound healing and transwell assays. Meanwhile, the levels of key proteins related to NSCLC cell apoptosis and PTEN/PI3K/AKT pathway were examined using Western blot assay. In addition, luciferase reporter assays were used to determine the interaction between WT1-AS and miR-494-3p or miR-494-3p and PTEN.

Results

Visibly downregulated WT1-AS in NSCLC cell lines was obtained from Broad Institute Cancer Cell Line Encyclopedia (CCLE) database and further verified by performing RT-qPCR. Besides, miR-494-3p was the downstream target gene of WT1-AS and obviously upregulated miR-494-3p in NSCLC cell lines was confirmed. WT1-AS overexpression suppressed cell proliferation, migration and invasion abilities while enhanced cell apoptosis of A549 and NCI-H1975 cells. Furthermore, upregulation of miR-494-3p distinctly reversed these inhibitory effects of WT1-AS overexpression on the tumorigenesis and progression of NSCLC. In addition, WT1-AS promoted PTEN expression and thereby inhibited activation of PI3K/AKT pathway by sponging miR-494-3p.

Conclusion

To conclude, lncRNA WT1-AS impeded cell proliferation, migration, invasion but accelerated cell apoptosis via negatively regulating miR-494-3p to mediate PTEN/PI3K/AKT pathway in NSCLC.

Circular RNA circ_0081001 knockdown enhances methotrexate sensitivity in osteosarcoma cells by regulating miR-494-3p/TGM2 axis

BACKGROUND

Circular RNAs (circRNAs) have been shown to participate in the chemoresistance and tumorigenesis of multiple cancers. The purpose of this research was to investigate the function of circ_0081001 in methotrexate (MTX) resistance of osteosarcoma (OS) and its potential molecular mechanism.

METHODS

The expression of circ_0081001, cytochrome P450 family 51 subfamily A member 1 (CYP51A1), and miR-494-3p was detected by qRT-PCR. Cell viability, apoptosis, migration, and invasion were evaluated by Cell Counting Kit-8 (CCK-8) assay, flow cytometry, and transwell assay, respectively. Western blot (WB) assay was used to measure the protein levels of cleaved-caspase3 (cleaved-casp3), E-cadherin, N-cadherin, and transglutaminase-2 (TGM2). The interaction between miR-494-3p and circ_0081001 or TGM2 was predicted by bioinformatics analysis and verified using the dual-luciferase reporter assay. The mice xenograft model was established to investigate the roles of circ_0081001 in MTX resistance of OS in vivo.

RESULTS

Circ_0081001 and TGM2 were upregulated, and miR-494-3p was downregulated in MTX-resistant OS tissues and cells. Moreover, circ_0081001 interference enhanced cell sensitivity to MTX through promoting apoptosis and inhibiting cell viability and metastasis in vitro. Furthermore, circ_0081001 was identified as a molecular sponge of miR-494-3p to upregulate TGM2 level. In addition, circ_0081001 knockdown inhibited MTX resistance via upregulating miR-494-3p and downregulating TGM2. Besides, circ_0081001 downregulation improved MTX sensitivity of OS in vivo.

CONCLUSION

Knockdown of circ_0081001 enhanced MTX sensitivity of OS cells through downregulating TGM2 by sponging miR-494-3p, elucidating a novel regulatory mechanism for chemoresistance of OS and providing a potential circRNA-targeted therapy for OS.

MicroRNA-494-3p inhibits formation of fast oxidative muscle fibres by targeting E1A-binding protein p300 in human-induced pluripotent stem cells

MYOD-induced microRNA-494-3p expression inhibits fast oxidative myotube formation by downregulating myosin heavy chain 2 (MYH2) in human induced pluripotent stem cells (hiPSCs) during skeletal myogenesis. However, the molecular mechanisms regulating MYH2 expression via miR-494-3p remain unknown. Here, using bioinformatic analyses, we show that miR-494-3p potentially targets the transcript of the E1A-binding protein p300 at its 3'-untranslated region (UTR). Myogenesis in hiPSCs with the Tet/ON-myogenic differentiation 1 (MYOD1) gene (MyoD-hiPSCs) was induced by culturing them in doxycycline-supplemented differentiation medium for 7 days. p300 protein expression decreased after transient induction of miR-494-3p during myogenesis. miR-494-3p mimics decreased the levels of p300 and its downstream targets MYOD and MYH2 and myotube formation efficiency. p300 knockdown decreased myotube formation efficiency, MYH2 expression, and basal oxygen consumption rate. The binding of miR-494-3p to the wild type p300 3'-UTR, but not the mutated site, was confirmed using luciferase assay. Overexpression of p300 rescued the miR-494-3p mimic-induced phenotype in MyoD-hiPSCs. Moreover, miR-494-3p mimic reduced the levels of p300, MYOD, and MYH2 in skeletal muscles in mice. Thus, miR-494-3p might modulate MYH2 expression and fast oxidative myotube formation by directly regulating p300 levels during skeletal myogenesis in MyoD-hiPSCs and murine skeletal muscle tissues.

Effects of Erbuzhuyu Decoction Combined with Acupuncture on Endometrial Receptivity Are Associated with the Expression of miR-494-3p

Background/Aim

Erbuzhuyu decoction (EBZYD) is a traditional Chinese medicine (TCM) formula and has been used in infertility treatment. Meanwhile, acupuncture is also used to treat female infertility. However, it is unclear whether EBZYD combined with acupuncture has better therapeutic effect. The aim of this study was to explore the effect of EBZYD combined with acupuncture and investigate its mechanism in superovulation mice.

Methods

The mice received the treatment of EBZYD, acupuncture, EBZYD combined with acupuncture, or miR-494-3p agomir combined with EBZYD and acupuncture. The blastocysts' number, endometrial microstructure, and endometrial thickness were observed, followed by the detection of endometrial receptivity-related factors, PI3K/Akt/mTOR pathway-related proteins, and miR-494-3p expression using quantitative real-time polymerase chain reaction (qRT-PCR) or western blot. Luciferase reporter assay was performed to confirm the targeting relationship between HOXA10 and miR-494-3p.

Results

EBZYD combined with acupuncture treatment could increase the number of blastocysts, pinopodes, endometrial thickness, and the expression of endometrial receptivity-related factors, and the treatment effect of EBZYD combined with acupuncture was better than EBZYD or acupuncture alone. In addition, EBZYD combined with acupuncture treatment activated PI3K/Akt/mTOR pathway and inhibited the expression of miR-494-3p. HOXA10 is one of the target genes of miR-494-3p. Overexpression of miR-494-3p reversed the therapeutic effect of EBZYD combined with acupuncture and suppressed the expression of HOXA10 and the activity of PI3K/Akt/mTOR pathway.

Conclusion

This study suggests that EBZYD combined with acupuncture could improve endometrial receptivity in superovulation mice via miR-494-3p/HOXA10 axis.

miRNA-425-5p enhances lung cancer growth via the PTEN/PI3K/AKT signaling axis

Background

miRNAs regulate a multitude of cellular processes and their aberrant regulation is linked to human cancer. However, the role of miR-425-5p in lung cancer (LCa) is still largely unclear. Here, we explored the role of miR-425-5p during LCa tumorigenesis.

Methods

Cell proliferation was evaluated by cell counting Kit-8 and colony formation assay. Western blot and real-time PCR were accordingly used to detect the relevant proteins, miRNA and gene expression. Luciferase reporter assays were used to illustrate the interaction between miR-425-5p and PTEN.

Results

We demonstrate that miR-425-5p is overexpressed in LCa tissue and enhances the proliferative and colony formation capacity of the LCa cell lines A549 and NCI-H1299. Through predictive binding assays, PTEN was identified as a direct gene target and its exogenous expression inhibited the pro-cancer effects of miR-425-5p. Through its ability to down-regulate PTEN, miR-425-5p activated the PI3K/AKT axis.

Conclusion

We conclude that miR-425-5p promotes LCa tumorigenesis through PTEN/PI3K/AKT signaling.

Loss of PTEN expression is associated with PI3K pathway-dependent metabolic reprogramming in hepatocellular carcinoma

Background

Metabolic reprogramming, in which energetic metabolism changes from oxidative phosphorylation to glycolysis, is well-accepted as a hallmark of cancers including hepatocellular carcinoma (HCC). A growing body of evidence suggests the involvement of oncogenes and tumor suppressor genes in the control of metabolic reprogramming. In this study, we attempt to investigate whether loss of PTEN, a recognized tumor suppressor, drives metabolic reprogramming of HCC.

Methods

Cancerous liver tissues were surgically resected from 128 HCC patients, with 43 adjacent noncancerous liver tissues as control. Aerobic glycolysis (Warburg effect) was reflected by measurements of glucose uptake and lactate production, mitochondrial membrane potential collapse was observed by JC-1 staining, glycolytic rate and mitochondrial respiration were evaluated by determining glycolytic proton efflux rate (glycoPER) and oxygen consumption rate (OCR) in cultured human HHCC cells.

Results

Reciprocal expression of PTEN and PI3K was determined in cancer liver tissues. Overexpression of PTEN suppressed the Warburg effect, as evidenced by reductions in glucose uptake and lactate production, maintenance of mitochondrial function, and transformation of energetic metabolism from glycolysis to oxidative phosphorylation in cultured PTEN-negative HHCC cells. Importantly, 740 Y-P, a PI3K agonist that leads to activation of the PI3K pathway, partially abrogated the function of PTEN and reprogramed glucose metabolism in cultured HHCC cells.

Conclusions

The discovery that loss of PTEN allows the tumor metabolic program has been a major advance in understanding the carcinogenesis of HCC.

miRNA/Target Gene Profile of Endothelial Cells Treated with Human Triglyceride-Rich Lipoproteins Obtained after a High-Fat Meal with Extra-Virgin Olive Oil or Sunflower Oil

SCOPE

The effects of triglyceride-rich lipoproteins (TRLs) on the miRNA expression of endothelial cells, which are very involved in atherosclerosis, according to the type of diet are not known.

METHODS AND RESULTS

The differences between the effects of TRLs isolated from blood of subjects after a high-fat meal with extra-virgin olive oil (EVOO) and sunflower oil (SO) on the microRNA-Seq profile related to atherosclerosis in human umbilical vein endothelial cells are analyzed. 28 upregulated microRNAs with EVOO-derived TRLs, which can regulate 22 genes related to atherosclerosis, are found. 21 upregulated microRNAs with SO-derived TRLs, which can regulate 20 genes related to atherosclerosis, are found. These microRNAs are mainly involved in angiogenesis, with a predominance of an anti-angiogenic effect with EVOO-derived TRLs. Other microRNAs upregulated with SO-derived TRLs are involved in cardiovascular diseases. Pathways for the target genes obtained from the upregulated microRNA with EVOO-derived TRLs are involved in lipid metabolism and inflammatory and defense response, while those with SO-derived TRLs are involved in lipid metabolic process.

CONCLUSION

EVOO-derived TRLs seem to produce a more atheroprotective profile than SO-derived TRLs. This study provides alternative mechanisms on the protective role of EVOO against the atherogenic process through microRNA regulation in endothelial cells.

Hydrazinocurcumin and 5-fluorouracil enhance apoptosis and restrain tumorigenicity of HepG2 cells via disrupting the PTEN-mediated PI3K/Akt signaling pathway

Hydrazinocurcumin (HZC), a curcumin analogue, serves as a tumor suppressor in breast cancer and lung cancer. In this study, we investigate the role and mechanism of HZC in regulating HepG2 cell apoptosis and tumorigenicity, and its synergistic effects with 5-fluorouracil (5-Fu). HepG2 cells were treated with HZC and/or 5-Fu to analyze the possible synergistic effects on cell proliferation, apoptosis and cell cycle distribution in vitro using EdU staining, Hoechst staining and flow cytometry, respectively. For mechanistic investigation we used pic, a phosphatase and tensin homolog (PTEN) inhibitor, and in other studies assessed the expression pattern of PTEN and PI3K/Akt signaling pathway-related genes. Additionally, we tested in vivo effects of HZC and 5-Fu treatment on growth of HepG2 cell tumors in nude mice. We found that HZC or 5-Fu induced apoptosis and repressed proliferation of HepG2 cells by upregulating the expression of PTEN and disrupting the PI3K/Akt signaling pathway activation. Moreover, HZC had a higher pro-apoptotic effect than 5-Fu. HZC and 5-Fu induced HepG2 cell apoptosis and inhibited their tumorigenicity in vivo. Inhibition of PTEN expression activated the PI3K/Akt signaling pathway and reversed the protective effects of HZC or 5-Fu. Thus, HZC and 5-Fu increase PTEN, which blocks the PI3K/Akt signaling pathway, ultimately inducing HepG2 cell apoptosis. Importantly, the synergistic combination of HZC and 5-Fu may present promising strategy for the treatment of HCC.

Identification lncRNA LOC102551149/miR-23a-5p pathway in hepatic fibrosis

BACKGROUND

Hepatic fibrosis is a worldwide incurable disease; due to the complex and unclear mechanism, there lack the effective therapeutic targets. However, the mechanism of miR-23a-5p underling this pathological process is largely not clear. The purpose of this study was to investigate the role of miR-23a-5p in hepatic fibrosis and HSC activation.

METHODS

The content of miR-23a-5p in hepatic fibrosis induced by N-nitrosodimethylamine (NDMA) and HSC activation induced by platelet-derived growth factor (PDGF) was detected by qRT-PCR. H&E staining, Masson staining and Shear wave electrography (SWE) were used to detect the degree of hepatic fibrosis. Immunohistochemistry staining, qRT-PCR and Western blot detect the related markers of liver fibrosis or HSC activation, as well as the related pathway genes and proteins. Dual-luciferase reporter system verifies the interaction between miR-23a-5p with PTEN or miR-23a-5p with lncRNA LOC102551149 in HSC-T6. siRNA and miRNA mimic transfer to HSC-T6 to detect the function of lncRNA LOC102551149 and miR-23a-5p on HSC activation.

RESULTS

After hepatic fibrosis and HSC activation happened, the expression of miR-23a-5p was up-regulated, whereas anti-miR-23a-5p can alleviate hepatic fibrosis and HSC activation. Further research shows miR-23a-5p can target PTEN and degrade it, causing activation of PI3K/Akt/mTOR/Snail pathway. lncRNA LOC102551149 can be used as a competition endogenous RNA (ceRNA) targeting miR-23a-5p through base pairing, and siRNA LOC102551149 or exogenous miR-23a-5p can induce HSC activation through PI3K/Akt/mTOR/Snail pathway.

CONCLUSION

We demonstrate mechanism pathway of miR-23a-5p on hepatic fibrosis and HSC activation, which may develop a therapeutic target for hepatic fibrosis.

The Complex Landscape of PTEN mRNA Regulation

Phosphatase and tensin homolog deleted on chromosome 10 (PTEN) is a key tumor suppressor in the development and progression of different tumor types. Emerging data indicate that small reductions in PTEN protein levels can promote cancer. PTEN protein levels are tightly controlled by a plethora of mechanisms beginning with epigenetic and transcriptional regulation and ending with control of protein synthesis and stability. PTEN messenger RNA (mRNA) is also subject to exquisite regulation by microRNAs, coding and long noncoding RNAs, and RNA-binding proteins. Additionally, PTEN mRNA is markedly influenced by alternative splicing and variable polyadenylation. Herein we provide a synoptic description of the current understanding of the complex regulatory landscape of PTEN mRNA regulation including several specific processes that modulate its stability and expression, in the context of PTEN loss-associated cancers.

The Non-coding Side of Medulloblastoma

Medulloblastoma (MB) is the most common pediatric brain tumor and a primary cause of cancer-related death in children. Until a few years ago, only clinical and histological features were exploited for MB pathological classification and outcome prognosis. In the past decade, the advancement of high-throughput molecular analyses that integrate genetic, epigenetic, and expression data, together with the availability of increasing wealth of patient samples, revealed the existence of four molecularly distinct MB subgroups. Their further classification into 12 subtypes not only reduced the well-characterized intertumoral heterogeneity, but also provided new opportunities for the design of targets for precision oncology. Moreover, the identification of tumorigenic and self-renewing subpopulations of cancer stem cells in MB has increased our knowledge of its biology. Despite these advancements, the origin of MB is still debated, and its molecular bases are poorly characterized. A major goal in the field is to identify the key genes that drive tumor growth and the mechanisms through which they are able to promote tumorigenesis. So far, only protein-coding genes acting as oncogenic drivers have been characterized in each MB subgroup. The contribution of the non-coding side of the genome, which produces a plethora of transcripts that control fundamental biological processes, as the cell choice between proliferation and differentiation, is still unappreciated. This review wants to fill this major gap by summarizing the recent findings on the impact of non-coding RNAs in MB initiation and progression. Furthermore, their potential role as specific MB biomarkers and novel therapeutic targets is also highlighted.

LncRNA NNT-AS1 promote glioma cell proliferation and metastases through miR-494-3p/PRMT1 axis

Long noncoding RNAs (lncRNAs) are key players in cancer progression. However, the function of lncRNA NNT-AS1 on glioma is unclear. In the present study, a total of 73 tumor tissues and matched adjacent non-tumor tissues were collected, and glioma cell lines were cultured in vitro. mRNA expression was tested using RT-qPCR. The protein expression level was determined using the western blot assay, cell proliferation was measured using the CCK-8 and BrdU proliferation assay, and the cell cycle, cell migration and invasion were determined using flow cytometry analysis, the wound healing assay and transwell, respectively. The results showed that lncNNT-AS1 is significantly up-regulated during the early stages of glioma. In particular, high levels of NNT-AS1 are observed in glioma cell lines compared to human astrocyte (HA) cells. Furthermore, the inhibition of lnc-NNT-AS1 by siRNA interfere attenuates the cell viability, proliferation, migration and invasion of glioma cell lines. Mechanistically, the inhibition of NNT-AS1 directly interacted with miRNA-494-3p, and positively regulated the downstream target PRMT1 in vitro. Further study proved that the overexpression of miRNA-494-3p and the inhibition of PRMT1 could attenuate both glioma cell proliferation and metastases. Collectively, our results indicated that the miR-494-3p-PRMT1 axis is involved the tumor-suppressive effects of NNT-AS1 inhibition, which sheds new light on lncRNA-directed diagnostics and the therapeutics of glioma.

Prognostic role of 14q32.31 miRNA cluster in various carcinomas: a systematic review and meta-analysis

Deregulated miR-379/miR-656 cluster expression is considered as important for carcinogenesis and can be used as a potential prognostic marker. Hence, the meta-analysis was conducted to test the utility of miR-379/miR-656 cluster as a prognostic marker in various cancers. A literature search was performed using Web of Science, PubMed and Cochrane Library to obtain relevant studies and were subjected to various subgroup and bioinformatics analyses. Selected twenty-three studies contained 13 cancer types comprising of 3294 patients from 7 nations. Univariate and multivariate data showed an association of high expression of miRNAs with the poor prognosis of cancer patients (p < 0.001). The subgroup analysis showed that lung cancer, breast cancer and papillary renal cell carcinoma (p < 0.001) have a negative association with the survival of patients. Our study is the first meta-analysis showing the association of miR-379/miR-656 cluster expression and overall survival, suggesting its potential as a prognostic indicator in multiple cancers.

miR-145-5p Acts as a Novel Tumor Suppressor in Hepatocellular Carcinoma Through Targeting RAB18

Micro-RNAs play critical roles in initiation and progression of hepatocellular carcinoma. However, the biological role of microRNA-145-5p in hepatocellular carcinoma and how it works are still not clearly understood. Expression levels of microRNA-145-5p in hepatocellular carcinoma cell lines were examined by reverse transcription quantitative polymerase chain reaction. Cell counting kit-8, wound-healing assay, and flow cytometry assay were conducted to investigate the role of microRNA-145-5p von proliferation, migration, and apoptosis. Luciferase reporter assay and Western blot were performed to investigate the correlation between microRNA-145-5p and RAB18. We found microRNA-145-5p was downregulated in hepatocellular carcinoma cell lines compared to the normal cell line. Overexpression of microRNA-145-5p inhibited the proliferation and migration but promoted apoptosis of hepatocellular carcinoma cells in vitro. RAB18 was validated a target of microRNA-145-5p and ectopic expression of RAB18 can promote the proliferation and migration but inhibit apoptosis of hepatocellular carcinoma cells. These findings indicate that microRNA-145-5p functions as a novel tumor suppressor through targeting RAB18, suggesting that microRNA-145-5p might be a potential new therapeutic molecule for the treatment of hepatocellular carcinoma.

Long Noncoding RNA TP73-AS1 Modulates Medulloblastoma Progression In Vitro And In Vivo By Sponging miR-494-3p And Targeting EIF5A2

Background

Previous studies have shown that P73 antisense RNA 1T (non-protein coding), also known as TP73-AS1, is a long non-coding RNA (lncRNA) and involved in the development of medulloblastoma. However, the regulatory mechanism of lncRNA TP73-AS1 in medulloblastoma was still unclear, the present study was aimed to investigate the detailed functions and the mechanism of TP73-AS1 in regulation of medulloblastoma.

Materials and methods

The levels of TP73-AS1, miR-494-3p, and Eukaryotic initiation factor 5A2 (EIF5A2) were determined using quantitative real-time PCR (qRT-PCR), in situ hybridization (ISH), or Immunohistochemistry (IHC). The function of TP73-AS1 in proliferation, apoptosis, migration, and invasion of medulloblastoma cells was evaluated using cell counting Kit-8 (CCK-8), flow cytometry, and transwell assay, respectively. The protein levels were determined by Western blot. Bioinformatics analysis and dual-luciferase reporter assay, RNA immunoprecipitation (RIP) and pull-down assay were used to search and confirm the target gene of TP73-AS1 and miR-494-3p. The effect of TP73-AS1 knockdown in vivo was detected by animal experiment.

Results

The levels of TP73-AS1 and EIF5A2 were up-regulated, while miR-494-3p expression was down-regulated in medulloblastoma tissues and cells, ELF5A2 was a direct target of miR-494-3p, and miR-494-3p bound to TP73-AS1. The knockdown of TP73-AS1 inhibited cell proliferation, invasion, migration, and promoted apoptosis of medulloblastoma cells, while the miR-494-3p inhibitor abolished the effects of TP73-AS1 knockdown on medulloblastoma cells.

Conclusion

TP73-AS1 positively regulated EIF5A2 expression by sponging miR-494-3p. These findings suggested that TP73-AS1 served as an oncogene and promoted the progression of medulloblastoma.

Non-coding RNAs: Emerging Regulators of Sorafenib Resistance in Hepatocellular Carcinoma

As the first oral multi-target anti-tumor drug proved for the treatment of patients with advanced liver cancer in 2007, sorafenib has changed the landscape of advanced hepatocellular carcinoma (HCC) treatment. However, drug resistance largely hinders its clinical application. Non-coding RNAs (ncRNAs), including microRNAs (miRNAs), and long non-coding (lncRNAs), have recently been demonstrated playing critical roles in a variety of cancers including HCC, while the mechanisms of ncRNAs in HCC sorafenib resistance have not been extensively characterized yet. Herein, we summarize the mechanisms of recently reported ncRNAs involved in sorafenib resistance and discuss the potential strategies for their application in the battle against HCC.

RAS/RAF/MEK/ERK, PI3K/PTEN/AKT/mTORC1 and TP53 pathways and regulatory miRs as therapeutic targets in hepatocellular carcinoma

Introduction: Hepatocellular carcinoma (HCC) is a significant problem globally because of viral infections and the increasing incidence of obesity and fatty liver disease. However, it is difficult to treat because its inherent genetic heterogeneity results in activation of numerous signaling pathways. Kinases have been targeted for decades with varying results, but the development of therapeutic resistance is a major challenge.Areas covered: The key roles of the RAS/RAF/MEK/ERK, PI3K/PTEN/AKT/mTORC1, TP53 microRNAs (miRs) as therapeutic targets are discussed and we suggests novel approaches for targeting miRs or their downstream targets to combat HCC. We performed literature searches using the Medline Database from 2000 to the present.Expert opinion: The involvement of RAS/RAF/MEK/ERK, PI3K/PTEN/AKT/mTORC and TP53 pathways as drivers of the disease and drug resistance is a challenge. Moreover, miRs regulate the expression of key genes in these pathways. What we and others are proposing is the prospect of targeting miRs and their downstream targets to improve conventional approaches to treat HCC. Combination approaches are often promising because multiple signaling pathways are deregulated due to diverse mutations and events.

Circular RNAs in Clear Cell Renal Cell Carcinoma: Their Microarray-Based Identification, Analytical Validation, and Potential Use in a Clinico-Genomic Model to Improve Prognostic Accuracy

Circular RNAs (circRNAs) may act as novel cancer biomarkers. However, a genome-wide evaluation of circRNAs in clear cell renal cell carcinoma (ccRCC) has yet to be conducted. Therefore, the objective of this study was to identify and validate circRNAs in ccRCC tissue with a focus to evaluate their potential as prognostic biomarkers. A genome-wide identification of circRNAs in total RNA extracted from ccRCC tissue samples was performed using microarray analysis. Three relevant differentially expressed circRNAs were selected (circEGLN3, circNOX4, and circRHOBTB3), their circular nature was experimentally confirmed, and their expression-along with that of their linear counterparts-was measured in 99 malignant and 85 adjacent normal tissue samples using specifically established RT-qPCR assays. The capacity of circRNAs to discriminate between malignant and adjacent normal tissue samples and their prognostic potential (with the endpoints cancer-specific, recurrence-free, and overall survival) after surgery were estimated by C-statistics, Kaplan-Meier method, univariate and multivariate Cox regression analysis, decision curve analysis, and Akaike and Bayesian information criteria. CircEGLN3 discriminated malignant from normal tissue with 97% accuracy. We generated a prognostic for the three endpoints by multivariate Cox regression analysis that included circEGLN3, circRHOBT3 and linRHOBTB3. The predictive outcome accuracy of the clinical models based on clinicopathological factors was improved in combination with this circRNA-based signature. Bootstrapping as well as Akaike and Bayesian information criteria confirmed the statistical significance and robustness of the combined models. Limitations of this study include its retrospective nature and the lack of external validation. The study demonstrated the promising potential of circRNAs as diagnostic and particularly prognostic biomarkers in ccRCC patients.

HOTAIR/miR-214-3p/FLOT1 axis plays an essential role in the proliferation, migration, and invasion of hepatocellular carcinoma

BACKGROUND

Long non-coding RNA (lncRNA) Hox transcript antisense intergenic RNA (HOTAIR) has been reported to play an important role in hepatocellular carcinoma (HCC) progression. Although there is evidence on HOTAIR being associated with HCC progression, the underlying mechanism remains to be further clarified.

METHODS

HOTAIR, miR-214-3p and FLOT1 expression were measured by quantitative real-time PCR or western blot. Cell proliferation, migration, and invasion were displayed by transwell assay, MTT, and colony formation assay. The relationship between HOTAIR, miR-214-3p, and FLOT1 was investigated by luciferase reporter assay. Tumor suppressive effect of HOTAIR was displayed by HepG2 xenografting to nude mice.

RESULTS

HOTAIR and FLOT1 expression were significantly up-regulated, whereas miR-214-3p was obviously down-regulated. Also, down-regulation of HOTAIR and FLOT1 as well as up-regulation of miR-214-3p inhibited cell proliferation, invasion, and migration. Intriguingly, the effects of miR-214-3p overexpression on HCC cells were rescued by high expression of HOTAIR. Otherwise, HOTAIR regulated FLOT1 expression through targeting miR-214-3p in HCC cells. Simultaneously, low HOTAIR expression inhibited FLOT1 expression by up-regulating miR-214-3p, which suppressed tumor growth in vivo.

CONCLUSION

HOTAIR expression indirectly regulated FLOT1 expression through endogenous competition with miR-214-3p. HOTAIR/miR-214-3p/FLOT1 axis affected the cell proliferation, migration, and invasion of HCC.

Up-Regulation of Phosphatase in Regenerating Liver-3 (PRL-3) Contributes to Malignant Progression of Hepatocellular Carcinoma by Activating Phosphatase and Tensin Homolog Deleted on Chromosome Ten (PTEN)/Phosphoinositide 3-Kinase (PI3K)/AKT Signaling Pathway

BACKGROUND The purpose of the study was to investigate the functional roles of phosphatase in regenerating liver-3 (PRL-3) in hepatocellular carcinoma (HCC), as well as the related molecular mechanisms. MATERIAL AND METHODS HCC tissues and adjacent normal tissues were collected from 124 HCC patients. The mRNA and protein levels of PRL-3 were detected using quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot assays, respectively. The relationship between PRL-3 expression and clinical characteristics of HCC patients was evaluated by chi-square test. MTT and Transwell assays were performed to estimate cell proliferation and motility, respectively. RESULTS The expression of PRL-3 was significantly increased in HCC tissues and cells at both protein and mRNA levels (P<0.01 for all). Furthermore, the up-regulation of PRL-3 was positively correlated with hepatic vascular invasion (P=0.019), lymph node metastasis (P=0.012), and TNM stage (P=0.001). The knockdown of PRL-3 suppressed HCC cell proliferation, migration, and invasion, and PR3K/AKT pathway activity was also obviously inhibited in HCC cells with PRL-3 deficiency. The levels of PTEN were negatively associated with PRL-3 expression. PRL-3 might inhibit the protein level of PTEN through enhancing its phosphorylation level. The transfection of si-PTEN can reverse the anti-tumor action caused by PRL-3 knockdown in HCC cells. CONCLUSIONS Up-regulation of PRL-3 may activate the PI3K/AKT signaling pathway and enhance malignant progression of HCC through targeting PTEN.