miR-133b inhibits glioma cell proliferation and invasion by targeting Sirt1

MiR-1976/NCAPH/P65 axis inhibits the malignant phenotypes of lung adenocarcinoma

Lung adenocarcinoma (LUAD) is a malignancy with an abysmal survival rate. High metastasis is the leading cause of the low survival rate of LUAD. NCAPH, an oncogene, is involved in the carcinogenesis of LUAD. However, the regulation of NCAPH in LUAD remains controversial. In this work, we identified an up-regulation of NCAPH in LUAD tissues. Patients who expressed more NCAPH had shorter overall survival (OS). Furthermore, NCAPH overexpression promoted LUAD cell migration while inhibiting apoptosis. MiR-1976 and miR-133b were predicted to target NCAPH expression by searching TargetScan and linkedomics databases. Following that, we confirmed that miR-1976 suppressed NCAPH by directly targeting a 7-bp region of NCAPH 3' untranslated regions (UTR). In addition, increased expression of miR-1976 decreased the proliferation & migration and promoted apoptosis of LUAD cells, and the re-introduction of NCAPH reversed these influences. Furthermore, the xenograft and metastasis mouse models also confirmed that miR-1976 inhibited tumor growth and metastasis in vivo by targeting NCAPH. Finally, we found that MiR-1976 targeting NCAPH blocked the activation of NF-κB. In conclusion, miR-1976 inhibits NCAPH activity in LUAD and acts as a tumor suppressor. The miR-1976/NCAPH/NF-κB axis may, in the future, represent crucial diagnostic and prognostic biomarkers and promising therapeutic options.

Biological, diagnostic and therapeutic implications of exosomes in glioma

Despite therapeutic advances, overall survival in glioblastoma is dismal. To optimize progress, a more detailed understanding of glioma's molecular, cellular, and intercellular pathophysiology is needed. Recent investigation has revealed a vital role for exosomes in inter-cellular signaling, tumor cell support, and regulation of the tumor microenvironment. Exosomes carry miRNAs, lncRNAs, mRNAs, proteins, immune regulatory molecules, nucleic acids, and lipids; however, the composition of exosome cargo is variable depending on the cell of origin. Specific exosomal miRNA contents such as miR-21, miR-301a, miR-151a, miR-148a, and miR-5096 are altered in high-grade glioma. Unique proteomic, genomic, and miRNA signatures of tumor exosomes have been associated with disease pathobiology, temozolomide resistance, immunosuppression, and tumor proliferation. Exosomes hold promise for tissue diagnostic glioma diagnosis and monitoring response to therapy. This review summarizes the current understanding of exosomes, their crucial role in glioma pathology, and future directions for their use in diagnosis and treatment. METHODS: The MEDLINE/PubMed database was reviewed for papers written in English and publication dates of 1981-2023, using the search string "Exosome", "Extracellular vesicles", "Glioma", "Exosomes in glioma".

Activated SIRT1 contributes to DPT-induced glioma cell parthanatos by upregulation of NOX2 and NAT10

Parthanatos is a type of programmed cell death dependent on hyper-activation of poly (ADP-ribose) polymerase 1 (PARP-1). SIRT1 is a highly conserved nuclear deacetylase and often acts as an inhibitor of parthanatos by deacetylation of PARP1. Our previous study showed that deoxypodophyllotoxin (DPT), a natural compound isolated from the traditional herb Anthriscus sylvestris, triggered glioma cell death via parthanatos. In this study, we investigated the role of SIRT1 in DPT-induced human glioma cell parthanatos. We showed that DPT (450 nmol/L) activated both PARP1 and SIRT1, and induced parthanatos in U87 and U251 glioma cells. Activation of SIRT1 with SRT2183 (10 μmol/L) enhanced, while inhibition of SIRT1 with EX527 (200 μmol/L) or knockdown of SIRT1 attenuated DPT-induced PARP1 activation and glioma cell death. We demonstrated that DPT (450 nmol/L) significantly decreased intracellular NAD+ levels in U87 and U251 cells. Further decrease of NAD+ levels with FK866 (100 μmol/L) aggravated, but supplement of NAD+ (0.5, 2 mmol/L) attenuated DPT-induced PARP1 activation. We found that NAD+ depletion enhanced PARP1 activation via two ways: one was aggravating ROS-dependent DNA DSBs by upregulation of NADPH oxidase 2 (NOX2); the other was reinforcing PARP1 acetylation via increase of N-acetyltransferase 10 (NAT10) expression. We found that SIRT1 activity was improved when being phosphorylated by JNK at Ser27, the activated SIRT1 in reverse aggravated JNK activation via upregulating ROS-related ASK1 signaling, thus forming a positive feedback between JNK and SIRT1. Taken together, SIRT1 activated by JNK contributed to DPT-induced human glioma cell parthanatos via initiation of NAD+ depletion-dependent upregulation of NOX2 and NAT10.

Comparison of Oncogenes, Tumor Suppressors, and MicroRNAs Between Schizophrenia and Glioma: The Balance of Power

The risk of cancer in schizophrenia has been controversial. Confounders of the issue are cigarette smoking in schizophrenia, and antiproliferative effects of antipsychotic medications. The author has previously suggested comparison of a specific cancer like glioma to schizophrenia might help determine a more accurate relationship between cancer and schizophrenia. To accomplish this goal, the author performed three comparisons of data; the first a comparison of conventional tumor suppressors and oncogenes between schizophrenia and cancer including glioma. This comparison determined schizophrenia has both tumor-suppressive and tumor-promoting characteristics. A second, larger comparison between brain-expressed microRNAs in schizophrenia with their expression in glioma was then performed. This identified a core carcinogenic group of miRNAs in schizophrenia offset by a larger group of tumor-suppressive miRNAs. This proposed "balance of power" between oncogenes and tumor suppressors could cause neuroinflammation. This was assessed by a third comparison between schizophrenia, glioma and inflammation in asbestos-related lung cancer and mesothelioma (ALRCM). This revealed that schizophrenia shares more oncogenic similarity to ALRCM than glioma.

Exosomal microRNA-133b-3p from bone marrow mesenchymal stem cells inhibits angiogenesis and oxidative stress via FBN1 repression in diabetic retinopathy

Diabetic retinopathy (DR) is a common microvascular complication. Many studies have focused on the role of microRNAs (miRNAs) in DR but not specifically on miR-133b-3p. Thus, this study is to unmask the mechanisms of miR-133b-3p in DR. KK/Upj-Ay mice (a spontaneous diabetic nephropathy model of DM, referred to as DR mice) were used in the study, and retinal tissues were collected. Bone marrow mesenchymal stem cells (BMSCs) were isolated and identified. High glucose (HG)-treated mouse retinal microvascular endothelial cells (mRMECs) were transfected or co-cultured with BMSCs-derived exosomes. Then, cell proliferation, migration, apoptosis, angiogenesis, and oxidative stress were observed. MiR-133b-3p and FBN1 expression in tissues and cells was detected. MiR-133b-3p expression was reduced, and FBN1 expression was increased in retinal tissues of DR mice and HG-treated mRMECs. Up-regulating miR-133b-3p or down-regulating FBN1 or BMSCs-derived exosomes impaired oxidative stress, angiogenesis, proliferation, migration, and promoted apoptosis of HG-treated mRMECs. This study has elucidated that exosomal miR-133b-3p from BMSCs suppresses angiogenesis and oxidative stress in DR via FBN1 repression.

Non-coding RNAs and glioblastoma: Insight into their roles in metastasis

Glioma, also known as glioblastoma multiforme (GBM), is the most prevalent and most lethal primary brain tumor in adults. Gliomas are highly invasive tumors with the highest death rate among all primary brain malignancies. Metastasis occurs as the tumor cells spread from the site of origin to another site in the brain. Metastasis is a multifactorial process, which depends on alterations in metabolism, genetic mutations, and the cancer microenvironment. During recent years, the scientific study of non-coding RNAs (ncRNAs) has led to new insight into the molecular mechanisms involved in glioma. Many studies have reported that ncRNAs play major roles in many biological procedures connected with the development and progression of glioma. Long ncRNAs (lncRNAs), microRNAs (miRNAs), and circular RNAs (circRNAs) are all types of ncRNAs, which are commonly dysregulated in GBM. Dysregulation of ncRNAs can facilitate the invasion and metastasis of glioma. The present review highlights some ncRNAs that have been associated with metastasis in GBM. miRNAs, circRNAs, and lncRNAs are discussed in detail with respect to their relevant signaling pathways involved in metastasis.

Redox modulation by plant polyphenols targeting vitagenes for chemoprevention and therapy: Relevance to novel anti-cancer interventions and mini-brain organoid technology

The scientific community, recently, has focused notable attention on the chemopreventive and therapeutic effects of dietary polyphenols for human health. Emerging evidence demonstrates that polyphenols, flavonoids and vitamins counteract and neutralize genetic and environmental stressors, particularly oxidative stress and inflammatory process closely connected to cancer initiation, promotion and progression. Interestingly, polyphenols can exert antioxidant or pro-oxidant cytotoxic effects depending on their endogenous concentration. Notably, polyphenols at high dose act as pro-oxidants in a wide type of cancer cells by inhibiting Nrf2 pathway and the expression of antioxidant vitagenes, such as NAD(P)H-quinone oxidoreductase (NQO1), glutathione transferase (GT), GPx, heme oxygenase-1 (HO-1), sirtuin-1 (Sirt1) and thioredoxin (Trx) system which play an essential role in the metabolism of reactive oxygen species (ROS), detoxification of xenobiotics and inhibition of cancer progression, by inducing apoptosis and cell cycle arrest according to the hormesis approach. Importantly, mutagenesis of Nrf2 pathway can exacerbate its "dark side" role, representing a crucial event in the initiation stage of carcinogenesis. Herein, we review the hormetic effects of polyphenols and nanoincapsulated-polyphenols in chemoprevention and treatment of brain tumors via activation or inhibition of Nrf2/vitagenes to suppress carcinogenesis in the early stages, and thus inhibit its progression. Lastly, we discuss innovative preclinical approaches through mini-brain tumor organoids to study human carcinogenesis, from basic cancer research to clinical practice, as promising tools to recapitulate the arrangement of structural neuronal tissues and biological functions of the human brain, as well as test drug toxicity and drive personalized and precision medicine in brain cancer.

Mesenchymal stem cell (MSC)-derived exosomes as novel vehicles for delivery of miRNAs in cancer therapy

Mesenchymal stem cells (MSCs) are known as promising sources for cancer therapy and can be utilized as vehicles in cancer gene therapy. MSC-derived exosomes are central mediators in the therapeutic functions of MSCs, known as the novel cell-free alternatives to MSC-based cell therapy. MSC-derived exosomes show advantages including higher safety as well as more stability and convenience for storage, transport and administration compared to MSCs transplant therapy. Unmodified MSC-derived exosomes can promote or inhibit tumors while modified MSC-derived exosomes are involved in the suppression of cancer development and progression via the delivery of several therapeutics molecules including chemotherapeutic drugs, miRNAs, anti-miRNAs, specific siRNAs, and suicide gene mRNAs. In most malignancies, dysregulation of miRNAs not only occurs as a consequence of cancer progression but also is directly involved during tumor initiation and development due to their roles as oncogenes (oncomiRs) or tumor suppressors (TS-miRNAs). MiRNA restoration is usually achieved by overexpression of TS-miRNAs using synthetic miRNA mimics and viral vectors or even downregulation of oncomiRs using anti-miRNAs. Similar to other therapeutic molecules, the efficacy of miRNAs restoration in cancer therapy depends on the effectiveness of the delivery system. In the present review, we first provided an overview of the properties and potentials of MSCs in cancer therapy as well as the application of MSC-derived exosomes in cancer therapy. Finally, we specifically focused on harnessing the MSC-derived exosomes for the aim of miRNA delivery in cancer therapy.

miR-376a inhibits glioma proliferation and angiogenesis by regulating YAP1/VEGF signalling via targeting of SIRT1

BACKGROUND

Glioma is the most common cancer in the central nervous system. Previous studies have revealed that the miR-376 family is crucial in tumour development; however, its detailed mechanism in glioma is not clear.

METHODS

Cellular mRNA or protein levels of miR-376a, SIRT1, VEGF and YAP1 were detected via qRT-PCR or Western blotting. We analysed the proliferation, angiogenesis and migration abilities of glioma cell lines using colony formation, tube formation and Transwell assays. A luciferase assay was performed to determine whether miR-376a could recognize SIRT1 mRNA. Xenograft experiments were performed to analyse the tumorigenesis capacity of glioma cell lines in nude mice. The angiogenesis marker CD31 in xenograft tumours was detected via immunohistochemistry (IHC).

RESULTS

miR-376a expression was lower in glioma cells than in normal astrocytes. miR-376a mimic inhibited SIRT1, YAP1, and VEGF expression and suppressed the proliferation, migration and angiogenesis abilities of the glioma cell lines LN229 and A172, whereas miR-376a inhibitor exerted the opposite functions. In a luciferase assay, miR-376a inhibited the luciferase activity of WT-SIRT1. SIRT1 overexpression upregulated YAP1 and VEGF in glioma cells and promoted proliferation, migration and angiogenesis. Xenografts with ectopic miR-376a expression exhibited lower volumes and weights and a slower growth curve. Overexpression of miR-376a inhibited YAP1/VEGF signalling and angiogenesis by inhibiting SIRT1 in xenograft tissues.

CONCLUSION

miR-376a directly targets and inhibits SIRT1 in glioma cells. Downregulation of SIRT1 resulted in decreased YAP1 and VEGF signalling, which led to suppression of glioma cell proliferation, migration and angiogenesis.

Recent Insight on the Non-coding RNAs in Mesenchymal Stem Cell-Derived Exosomes: Regulatory and Therapeutic Role in Regenerative Medicine and Tissue Engineering

Advances in the field of regenerative medicine and tissue engineering over the past few decades have paved the path for cell-free therapy. Numerous stem cell types, including mesenchymal stem cells (MSCs), have been reported to impart therapeutic effects via paracrine secretion of exosomes. The underlying factors and the associated mechanisms contributing to these MSC-derived exosomes' protective effects are, however, poorly understood, limiting their application in the clinic. The exosomes exhibit a diversified repertoire of functional non-coding RNAs (ncRNAs) and have the potential to transfer these biologically active transcripts to the recipient cells, where they are found to modulate a diverse array of functions. Altered expression of the ncRNAs in the exosomes has been linked with the regenerative potential and development of various diseases, including cardiac, neurological, skeletal, and cancer. Also, modulating the expression of ncRNAs in these exosomes has been found to improve their therapeutic impact. Moreover, many of these ncRNAs are expressed explicitly in the MSC-derived exosomes, making them ideal candidates for regenerative medicine, including tissue engineering research. In this review, we detail the recent advances in regenerative medicine and summarize the evidence supporting the altered expression of the ncRNA repertoire specific to MSCs under different degenerative diseases. We also discuss the therapeutic role of these ncRNA for the prevention of these various degenerative diseases and their future in translational medicine.

Advances in the role of silence information regulator family in pathological pregnancy

Aberrant maternal inflammation and oxidative stress are the two main mechanisms of pathological pregnancy. The silence information regulator (sirtuin) family is a highly conserved family of nicotinamide adenine dinucleotide (NAD)-dependent deacylases. By regulating the post-translational modification of proteins, sirtuin is involved in various biological processes including oxidative stress and inflammation. Nowadays, emerging evidence indicates that sirtuin may be closely related to the occurrence and development of pathological pregnancy. The down-regulation of sirtuin can cause spontaneous preterm delivery by promoting uterine contraction and rupture of fetal membranes, cause gestational diabetes mellitus through promoting oxidative stress and affecting the activity of key enzymes in glucose metabolism, cause preeclampsia by reducing the proliferation and invasion ability of trophoblasts, cause intrahepatic cholestasis of pregnancy by promoting the production of bile acids and T helper 1 cell (Th1) cytokines, and cause intrauterine growth restriction through inducing mitochondrial dysfunction. Moreover, the expression and activation of sirtuin can be modulated through dietary interventions, thus sirtuin is expected to become a new target for the prevention and treatment of pregnancy complications. This article reviews the role of the sirtuin family in the occurrence and development of pathological pregnancy and its influence on the development of the offspring.

ETS1-activated SNHG10 exerts oncogenic functions in glioma via targeting miR-532-3p/FBXL19 axis

Background

In past few years, long non-coding RNAs (lncRNAs) have been reported to play regulatory roles during cancer progression. LncRNA SNHG10 has been explored in several sorts of cancers. However, its detailed role and mechanism are still not well understood in glioma.

Methods

Expression levels of genes were evaluated by RT-qPCR. EdU, TUNEL, sphere formation, wound healing and transwell assays appraised the effect of SNHG10 on glioma cellular processes. The interaction between molecules was examined by ChIP, RIP, RNA pull down and luciferase reporter assays.

Results

High level of SNHG10 was detected in glioma cells. Functional assay confirmed that SNHG10 promoted the proliferation, migration, invasion and stemness of glioma cells. Moreover, miR-532-3p was validated to bind with SNHG10 and expressed at a low level in glioma cells. Importantly, miR-532-3p exerted inhibitory functions in glioma. Furthermore, it was found that FBXL19 targeted by miR-532-3p facilitated cell growth and stemness in glioma, and that SNHG10 worked in glioma by increasing FBXL19 expression through sequestering miR-532-3p. More importantly, ETS1 promoted the transcription of SNHG10 and it mediated contribution to the malignant behaviors of glioma cells by SNHG10/miR-532-3p/FBXL19 signaling.

Conclusion

SNHG10 was transcriptionally activated by ETS1 and played an oncogenic role in glioma by sponging miR-532-3p and up-regulating FBXL19.

Role of exosomes in malignant glioma: microRNAs and proteins in pathogenesis and diagnosis

Malignant gliomas are the most common and deadly type of central nervous system tumors. Despite some advances in treatment, the mean survival time remains only about 1.25 years. Even after surgery, radiotherapy and chemotherapy, gliomas still have a poor prognosis. Exosomes are the most common type of extracellular vesicles with a size range of 30 to 100 nm, and can act as carriers of proteins, RNAs, and other bioactive molecules. Exosomes play a key role in tumorigenesis and resistance to chemotherapy or radiation. Recent evidence has shown that exosomal microRNAs (miRNAs) can be detected in the extracellular microenvironment, and can also be transferred from cell to cell via exosome secretion and uptake. Therefore, many recent studies have focused on exosomal miRNAs as important cellular regulators in various physiological and pathological conditions. A variety of exosomal miRNAs have been implicated in the initiation and progression of gliomas, by activating and/or inhibiting different signaling pathways. Exosomal miRNAs could be used as therapeutic agents to modulate different biological processes in gliomas. Exosomal miRNAs derived from mesenchymal stem cells could also be used for glioma treatment. The present review summarizes the exosomal miRNAs that have been implicated in the pathogenesis, diagnosis and treatment of gliomas. Moreover, exosomal proteins could also be involved in glioma pathogenesis. Exosomal miRNAs and proteins could also serve as non-invasive biomarkers for prognosis and disease monitoring. Video Abstract.

The role of miRNA-133b and its target gene SIRT1 in FAP-derived desmoid tumor

Signaling pathways have a key role in driving the uncontrolled development of familial adenomatous polyposis (FAP)- associated and sporadic desmoid tumors (DTs).

The relationship between the Wnt/b-catenin signaling pathway and DTs has been extensively studied, but no reliable biomarkers able to detect their histological subtype have been identified for the accurate diagnosis.

In this study we studied the differences in miRNA expression between sporadic (20 patients) and FAP-associated DTs (7 patients) using microarray confirmed by quantitative PCR (qPCR). The analysis showed 19 dysregulated miRNAs. Among them miR-133b levels were significantly lower in FAP-associated DT than in sporadic DT. Therefore, two mRNAs, associated to miR-133b and β-catenin expression, the SIRT1 and ELAVL1were analyzed.

The qPCR analysis showed that SIRT1 mRNA levels were significantly up-regulated in FAP-associated DT than in sporadic DT, whereas no differences in ELAVL1 expression was observed between these two DT types. In addition, a negative correlation was observed between miR-133b and SIRT1 in FAP-associated DTs, but not in sporadic DTs.

The miR-133b-SIRT1-β-catenin axis may represent a novel mechanism underlying progression of FAP-associated DT.

Long noncoding RNA-GAS5 attenuates progression of glioma by eliminating microRNA-10b and Sirtuin 1 in U251 and A172 cells

Long noncoding RNA (lncRNA) growth arrest-specific 5 (GAS5) is implicated in several cancers via modulating microRNAs (miRs). However, little information is available about the correlation between GAS5 and miR-10b. Therefore, we sought out to investigate the biological role of GAS5-miR-10b node mainly in glioma cells. We artificially modulated GAS5 to explore its roles in viability assayed by cell counting kit-8 (CCK-8), motile activities by 24-Transwell assay, as well as apoptosis by a flow cytometer and Western blot assay. miR-10b and Sirtuin 1 (Sirt1) were quantified by qRT-PCR. After co-transfection, we analyzed the viability, migration, invasion, apoptosis, and Sirt1 expression. Western blot was implemented to detect the phosphorylated forms of PTEN, PI3K, AKT, MEK, and ERK. GAS5 inhibited proliferation and motile behaviors, and fortified apoptosis. As for the viability and motile activities, the property of GAS5 was reversed in miR-10b-replenished U251 and A172 cells, while maintained in miR-10b-deficient cells. Additionally, GAS5-induced apoptosis was abolished by miR-10b overexpression while fortified by miR-10b silence. Besides, GAS5 negatively modulated Sirt1 via miR-10b. Moreover, Sirt1 negatively modulated PTEN and positively mediated the abovementioned regulators. GAS5 represses the process of glioma cells by decreasing miR-10b, which as accompanied by Sirt1 silence-induced inactivation of PTEN/PI3K/AKT and MEK/ERK cascades.

Integrative Analysis of Sirtuins and Their Prognostic Significance in Clear Cell Renal Cell Carcinoma

Sirtuins, class III histone deacetylases, are involved in multiple biological processes in cancer initiation and progression. However, the diverse expression patterns and prognostic values of sirtuins in cancers have yet to be elucidated. In this study, we first evaluated the expression and prognostic values of sirtuins in multiple cancer cohorts using publicly available TCGA pan-cancer datasets. Pan-cancer survival analysis indicated that 6 out of 7 sirtuin family members were significant associated with prognosis of clear cell renal cell carcinoma (KIRC) patients. SIRT1, SIRT3, SIRT4, and SIRT5 were associated with favorable prognosis of KIRC patients, while SIRT6 and SIRT7 were associated with unfavorable prognosis. The expression levels of SIRT4 and SIRT5 in KIRC tissues were lower than that in normal tissues, while SIRT6 and SIRT7 were higher in KIRC tissues. The expression levels of SIRT1, SIRT3, SIRT5, SIRT6, and SIRT7 were significantly correlated with tumor stage and histological grade. DNA methylation may contribute to the dysregulation of sirtuins. Finally, GSEA was conducted to predict the potential functions of sirtuins in KIRC. Our results may provide novel insights for the development of sirtuins-based cancer therapy in KIRC.

Noninvasive quantification of SIRT1 expression-activity and pharmacologic inhibition in a rat model of intracerebral glioma using 2-[18F]BzAHA PET/CT/MRI

Background

Several studies demonstrated that glioblastoma multiforme progression and recurrence is linked to epigenetic regulatory mechanisms. Sirtuin 1 (SIRT1) plays an important role in glioma progression, invasion, and treatment response and is a potential therapeutic target. The aim of this study is to test the feasibility of 2-[¹⁸F]BzAHA for quantitative imaging of SIRT1 expression–activity and monitoring pharmacologic inhibition in a rat model of intracerebral glioma.

Methods

Sprague Dawley rats bearing 9L (N = 12) intracerebral gliomas were injected with 2-[¹⁸F]BzAHA (300–500 µCi/animal i.v.) and dynamic positron-emission tomography (PET) imaging was performed for 60 min. Then, SIRT1 expression in 9L tumors (N = 6) was studied by immunofluorescence microscopy (IF). Two days later, rats with 9L gliomas were treated either with SIRT1 specific inhibitor EX-527 (5 mg/kg, i.p.; N = 3) or with histone deacetylases class IIa specific inhibitor MC1568 (30 mg/kg, i.p.; N = 3) and 30 min later were injected i.v. with 2-[¹⁸F]BzAHA. PET-computerized tomography-magnetic resonance (PET/CT/MR) images acquired after EX-527 and MC1568 treatments were co-registered with baseline images.

Results

Standard uptake values (SUVs) of 2-[¹⁸F]BzAHA in 9L tumors measured at 20 min post-radiotracer administration were 1.11 ± 0.058 and had a tumor-to-brainstem SUV ratio of 2.73 ± 0.141. IF of 9L gliomas revealed heterogeneous upregulation of SIRT1, especially in hypoxic and peri-necrotic regions. Significant reduction in 2-[¹⁸F]BzAHA SUV and distribution volume in 9L tumors was observed after administration of EX-527, but not MC1568.

Conclusions

PET/CT/MRI with 2-[¹⁸F]BzAHA can facilitate studies to elucidate the roles of SIRT1 in gliomagenesis and progression, as well as to optimize therapeutic doses of novel SIRT1 inhibitors.

Mesenchymal stem cell-derived exosomal microRNA-133b suppresses glioma progression via Wnt/β-catenin signaling pathway by targeting EZH2

Background

Mesenchymal stem cells (MSCs) play a significant role in cancer initiation and metastasis, sometimes by releasing exosomes that mediate cell communication by delivering microRNAs (miRNAs). This study aimed to investigate the effects of exosomal miR-133b derived from MSCs on glioma cell behaviors.

Methods

Microarray-based analysis identified the differentially expressed genes (DEGs) in glioma. The expression patterns of EZH2 and miR-133b along with interaction between them were clarified in glioma. The expression of miR-133b and EZH2 in glioma cells was altered to examine their functions on cell activities. Furthermore, glioma cells were co-cultured with MSC-derived exosomes treated with miR-133b mimic or inhibitor, and EZH2-over-expressing vectors or shRNA against EZH2 to characterize their effect on proliferation, invasion, and migration of glioma cells in vitro. In vivo assays were also performed to validate the in vitro findings.

Results

miR-133b was downregulated while EZH2 was upregulated in glioma tissues and cells. miR-133b was found to target and negatively regulate EZH2 expression. Moreover, EZH2 silencing resulted in inhibited glioma cell proliferation, invasion, and migration. Additionally, MSC-derived exosomes containing miR-133b repressed glioma cell proliferation, invasion, and migration by inhibiting EZH2 and the Wnt/β-catenin signaling pathway. Furthermore, in vivo experiments confirmed the tumor-suppressive effects of MSC-derived exosomal miR-133b on glioma development.

Conclusion

Collectively, the obtained results suggested that MSC-derived exosomes carrying miR-133b could attenuate glioma development via disrupting the Wnt/β-catenin signaling pathway by inhibiting EZH2, which provides a potential treatment biomarker for glioma.

Long non‑coding RNA DLEU1 promotes cell proliferation of glioblastoma multiforme

Glioblastoma multiforme (GBM) is the most common malignant tumor with high morbidity and mortality. This study investigated the role of long non‑coding RNAs (lncRNAs) in glioblastomagenesis progression. Using the GSE2223 and GSE59612 datasets, and RNA sequencing data of GBM from The Cancer Genome Atlas, differentially expressed (DE) genes including DE messenger RNAs (DEmRNAs) and DElncRNAs between GBM and normal controls were identified. Based on the competing endogenous RNA hypothesis, DElncRNA‑micro RNA (miRNA)‑DEmRNA interactions were obtained by target gene prediction. Gene Ontology (GO) and Kyoto Encyclopedia of Gene and Genomes pathway analysis of DEmRNAs in the DElncRNA‑miRNA‑DEmRNA network was performed. Expression and function analyses of DElncRNAs were performed by reverse transcription‑polymerase chain reaction (RT‑PCR) and an established viability assay, respectively. In total, 712 DE genes were identified. Significant upregulation of lncRNA deleted in lymphocytic leukemia 1 (DLEU1) was revealed in GBM and a number of other types of cancer. DLEU1 interacted with 315 miRNAs and 105 DEmRNAs. The DEmRNAs were mainly enriched in tumorigenesis‑associated GO terms (angiogenesis, positive regulation of cell proliferation, positive regulation of fibroblast apoptotic processes and regulation of neutrophil migration) and pathways (Hippo signaling pathway, cancer pathways, and Wnt signaling pathway). Correlation analysis revealed that mRNA TNF receptor associated factor 4 (TRAF4) was associated with DLEU1 expression. RT‑PCR demonstrated that the expression levels of DLEU1 and TRAF4 were increased in GBM tissues. Small interfering RNA demonstrated that silencing DLEU1 downregulated TRAF4. The viability of GBM cells was significantly decreased following RNA interference with DLEU1 and TRAF4 production. The results demonstrate that DLEU1 and TRAF4 is highly expressed in GBM tissues and promotes proliferation of GBM cells. It may act as a competing endogenous RNA and influence tumorigenesis of GBM.

Discovery of 5-Signature Predicting Survival of Patients with Lower-Grade Glioma

OBJECTIVE

In the study, we aimed to identify key microRNAs (miRNAs) and clinical factors associated with survival time of lower-grade glioma (LGG) and develop an expression-based miRNA signature to provide survival risk prediction for patients with LGG.

METHODS

We obtained miRNA expression profiles and clinical information of patients with LGG from The Cancer Genome Atlas dataset. All 591 miRNAs were modeled using random Forest Survival, Regression, and Classification to construct a random forest model for survival analysis, and feature selection was performed. We used univariate and multivariate Cox regression analysis to screen differentially expressed miRNAs and clinical factors related to overall survival of patients with LGG.

RESULTS

A total of 591 differentially expressed miRNAs were obtained between LGG and normal tissues. After univariate and multivariate Cox regression analysis, 2 predictive miRNAs (hsa-miR-10b-5p and hsa-miR-15b-5p) and 3 clinical factors (grade, age, and cancer status) were finally screened out to construct a 5-signature, based on which patients in the training dataset were divided into high-risk and low-risk groups. The competitive performance of the 5-signature was revealed by receiver operating characteristic curve analysis. The prognostic value of the 5-signature was successfully validated in the testing and validation dataset.

CONCLUSIONS

Our study demonstrated the promising potential of the novel 5-signature as an independent biomarker for survival prediction of patients with LGG.

SF3B4 is regulated by microRNA-133b and promotes cell proliferation and metastasis in hepatocellular carcinoma

BACKGROUND

Splicing factor 3b subunit 4 (SF3B4) is a splicing factor and potential oncogene in hepatocellular carcinoma (HCC); however, its regulatory mechanism is yet unclear. We aimed to determine the role of SF3B4 in HCC and the underlying mechanism.

METHODS

To investigate the association between alternative splicing events and miRNAs, putative miRNAs were screened using TargetScan. Expression levels of and prognostic information for SF3B4 and miRNAs were determined based on public genomic data and clinical samples. Then, we examined the possible roles of SF3B4 and miRNA-133b in HCC cells and a xenograft mouse model. Pearson correlation analysis and in vitro experiments verified SF3B4 as a miRNA-133b target. Protein levels of key targets from the SF3B4 signaling pathway were estimated using western blotting.

FINDINGS

The expression of SF3B4 was upregulated in HCC tissues and cell lines whereas, the expression of miRNA-133b was downregulated. MiRNA-133b negatively regulated the expression of SF3B4. Effects of SF3B4 overexpression were partially abolished by miRNA-133b mimics, confirming that SF3B4 is a target of miRNA-133b. Moreover, molecules associated with SF3B4, including KLF4, KIP1, and SNAI2, were also modulated by miRNA-133b.

INTERPRETATION

SF3B4 plays a crucial role in HCC and is negatively regulated by miRNA-133b. The miRNA-133b/ SF3B4 axis may serve as a new therapeutic target for HCC treatment. FUND: China National Funds for Distinguished Young Scientists (No.81425019), the State Key Program of National Natural Science Foundation of China (No.81730076), Shanghai Science and Technology Committee Program (No.18XD1405300) and Specially-Appointed Professor Fund of Shanghai (GZ2015009). China National Funds for National Natural Science Fund (No.81672899).

MicroRNA-133b suppresses bladder cancer malignancy by targeting TAGLN2-mediated cell cycle

MicroRNAs (miRNAs), a group of small noncoding RNAs, are widely involved in the regulation of gene expression via binding to complementary sequences at 3'-untranslated regions (3'-UTRs) of target messenger RNAs. Recently, downregulation of miR-133b has been detected in various human malignancies. Here, the potential biological role of miR-133b in bladder cancer (BC) was investigated. In this study, we found the expression of miR-133b was markedly downregulated in BC tissues and cell lines (5637 and T24), and was correlated with poor overall survival. Notably, transgelin 2 (TAGLN2) was found to be widely upregulated in BC, and overexpression of TAGLN2 also significantly increased risks of advanced TMN stage. We further identified that upregulation of miR-133b inhibited glucose uptake, invasion, angiogenesis, colony formation and enhances gemcitabine chemosensitivity in BC cell lines by targeting TAGLN2. Additionally, we showed that miR-133b promoted the proliferation of BC cells, at least partially through a TAGLN2-mediated cell cycle pathway. Our results suggest a novel miR-133b/TAGLN2/cell cycle pathway axis controlling BC progression; a molecular mechanism which may offer a potential therapeutic target.

MiR-199a-5p regulates sirtuin1 and PI3K in the rat hippocampus with intrauterine growth restriction

In humans, malnutrition during pregnancy results in intrauterine growth restriction (IUGR) and an increased risk of neurological morbidities; altered miRNA characteristics have been suggested to contribute to IUGR neurological pathogenesis. A miRNA microarray was used to identify differentially expressed miRNA molecules in the hippocampi of rats with IUGR. Five of the molecules in question were selectively validated using real-time PCR in rats with IUGR. We then investigated the role of miR-199a-5p in hippocampal pathology. Bioinformatics analysis results suggested that TNF-α, caspase-3 and SIRT1 were potential targets of miR-199a-5p. Changes in PI3K, SIRT1 and caspase-3 protein expressions levels in the hippocampus were confirmed by Western blot analysis (all P < 0.05). Studies using the pheochromocytoma cell line PC12 cells and primary neurons demonstrated that miR-199a-5p modulated PI3K, caspase-3 and SIRT1 expression. Additionally, there was an inverse correlation between miR-199a-5p and caspase-3 expression, though dual-luciferase reporter assays showed that caspase-3 is not a target of miR-199a-5p. We conclude that IUGR affects hippocampal miRNAs characteristics. Our results also indicated that aberrantly high expression levels of miR-199a-5p may play an important role in the pathogenesis of IUGR by regulating SIRT1 and PI3K.

miR-133b and miR-199b knockdown attenuate TGF-β1-induced epithelial to mesenchymal transition and renal fibrosis by targeting SIRT1 in diabetic nephropathy

Transforming growth factor-β1 (TGF-β1)-induced epithelial to mesenchymal transition (EMT) and renal fibrosis plays critical role in the development and progression of diabetic nephropathy (DN). Our study aimed to determine the detailed roles of miR-133b & miR-199b on TGF-β1-induced EMT & renal fibrosis in DN and its underlying mechanism. The expressions of miR-133b & miR-199b in OLETF rats, LETO rats & TGF-β1-treated human proximal tubule cell line (HK-2) were examined by qRT-PCR. Inhibition of miR-133b or miR-199b was realized in cells by transfection of lentivirus containing miR-133b inhibit or miR-199b inhibitor. The expression levels of collagen I (COL I), fibronectin (FN), α-smooth muscle actin (α-SMA), E-cadherin & sirtuin 1 (SIRT1) were detected by western blot and immunohistochemistry. Masson staining was conducted to estimate the degree of renal fibrosis. The interaction between SIRT1 and miR-133b, miR-199b was explored by luciferase reporter assay and RNA immunoprecipitation (RIP) assay. miR-133b and miR-199b were highly expressed in the renal cortex of diabetic OLETF rats and TGF-β1-treated HK-2 cells. EMT and renal fibrosis were induced in diabetic OLETF rats and TGF-β1-treated HK-2 cells. Inhibition of miR-133b and miR-199b attenuated EMT and renal fibrosis in diabetic OLETF rats and TGF-β1-treated HK-2 cells. In addition, SIRT1 was identified as a target of miR-133b & miR-199b in HK-2 cells. SIRT1 knockdown dramatically reversed the suppression on TGF-β1-induced EMT and renal fibrosis in HK-2 cells mediated by anti-miR-133b or anti-miR-199. Inhibition of miR-133b & miR-199b attenuated TGF-β1-induced EMT & renal fibrosis by upregulating SIRT1 shows that using different miRNAs is a potential strategy for the future treatment of DN.

miR-133b, a particular member of myomiRs, coming into playing its unique pathological role in human cancer

MicroRNAs, a family of single-stranded and non-coding RNAs, play a crucial role in regulating gene expression at posttranscriptional level, by which it can mediate various types of physiological and pathological process in normal developmental progress and human disease, including cancer. The microRNA-133b originally defined as canonical muscle-specific microRNAs considering their function to the development and health of mammalian skeletal and cardiac muscles, but new findings coming from our group and others revealed that miR-133b have frequently abnormal expression in various kinds of human cancer and its complex complicated regulatory networks affects the tumorigenicity and development of malignant tumors. Very few existing reviews on miR-133b, until now, are principally about its role in homologous cluster (miR-1, −133 and -206s), however, most of constantly emerging new researches now are focused mainly on one of them, so In this article, to highlight the unique pathological role of miR-133b playing in tumor, we conduct a review to summarize the current understanding about one of the muscle-specific microRNAs, namely miR-133b, acting in human cancer. The review focused on the following four aspects: the overview of miR-133b, the target genes of miR-133b involved in human cancer, the expression of miR-133b and regulatory mechanisms leading to abnormal expression of miR-133b.

SIRT1 increases cardiomyocyte binucleation in the heart development

SIRT1 regulates cell senescence. We investigated a novel role of SIRT1 in the regulation of cardiomyocyte terminal differentiation in the developing heart. Retinoic acid (RA)-induced binucleation of H9c2 cells was associated with increased SIRT1 expression. Inhibition of SIRT1 activity or expression significantly decreased RA-induced binucleation. SIRT1 expression was minimal in the fetal heart and significantly upregulated in the hearts of postnatal day 7 (P7) rat pups. In contrast, heart-specific miR-133a expression was high in the fetal heart but significantly reduced in P7 pup hearts. The miR-133a promoter contains a canonical HRE element and hypoxia upregulated miR-133a gene expression in the heart. SIRT1 mRNA 3′UTR has miR-133a binding sequences and miR-133a and hypoxia suppressed SIRT1 expression in cardiomyocytes. Of importance, inhibition of SIRT1 significantly reduced binucleated cardiomyocytes in the hearts of P7 pups. Taken together, the present study reveals a novel role of SIRT1 and its regulation by miR-133a in cardiomyocyte terminal differentiation of the developing heart, and suggests a potential therapeutic strategy that may impact cardiac function later in life.

microRNA‑188 acts as a tumour suppressor in glioma by directly targeting the IGF2BP2 gene

Glioma is the most common and aggressive human brain tumour and accounts for ~35‑61% of intracranial tumours. Despite considerable advances in treatments for glioma, the prognosis for patients with this disease remains unsatisfactory. MicroRNAs (miRNAs of miRs) are small regulatory RNA molecules that have been identified as being involved in the initiation and progression of human cancers, and represent novel therapeutic targets for anticancer treatments. The dysregulation of miR‑188 has been reported in various kinds of human cancer. However, its expression pattern, biological roles and potential mechanism in glioma remain unknown. Expression levels of miR‑188 in glioma tissues and cell lines were detected through reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR). Cell Counting Kit-8 assays and migration and invasion assays were used to explore the effects of miR‑188 on the proliferation, migration and invasion of glioma cells, respectively. Bioinformatics analysis and luciferase reporter assays were performed to examine insulin‑like growth factor 2 mRNA-binding protein 2 (IGF2BP2) as a target gene of miR‑188. RT‑qPCR and Spearman's correlation analysis were then performed to measure IGF2BP2 mRNA expression in clinical glioma tissues and its correlation with miR‑188 expression. The regulatory effect of miR‑188 on IGF2BP2 expression was also investigated through RT‑qPCR and western blotting analysis. Finally, the biological roles of IGF2BP2 in glioma cells were assessed. miR‑188 levels were significantly reduced in glioma tissues and cell lines compared with adjacent normal tissues and normal human astrocytes, respectively. In addition, miR‑188 overexpression suppressed cell proliferation, migration and invasion of glioma. The present study identified IGF2BP2 as a direct target of miR‑188 in glioma, and IGF2BP2 under‑expression served tumour‑suppressive roles in glioma growth and metastasis. Thus, miR‑188 had a similar role in glioma by inhibiting the action of its downstream target, IGF2BP2. Therefore, miR‑188 may be a potential therapeutic target for the prevention and treatment of patients with glioma.

miR-133b suppresses metastasis by targeting HOXA9 in human colorectal cancer

Functions and mechanisms of microRNA (miRNA) involved in colorectal cancer (CRC) metastasis are largely unknown. Here, a miRNA microarray analysis was performed in CRC primary tissues and metastatic hepatic tissues to disclose crucial miRNA involved in CRC metastasis. MiR-133b was decreased and negatively correlated with metastasis in CRC. Overexpression of miR-133b significantly suppressed metastasis of CRC in vitro and in vivo. HOXA9 was identified as a direct and functional target of miR-133b. In addition, HOXA9 was negatively correlated with miR-133b and promoted CRC malignant progress. Moreover, miR-133b decreased HOXA9 expression, and subsequently downregulated ZEB1 and upregulated E-cadherin expression. Intriguingly, lower miR-133b and higher HOXA9 expression significantly contributed to poorer outcomes in CRC patients. Multivariate analysis indicated that miR-133b was an independent and significant predictor of CRC patient overall survival. In conclusion, we newly determined that miR-133b targeted the HOXA9/ZEB1 pathway to promote tumor metastasis in CRC cells. This axis provided insights into the mechanism underlying miRNA regulation of CRC metastasis and a novel therapeutic target for CRC treatment.