MicroRNA-378 enhances inhibitory effect of curcumin on glioblastoma

Action of Curcumin on Glioblastoma Growth: A Systematic Review with Meta-Analysis of Animal Model Studies

Gliomas are aggressive brain tumors with poor prognosis even after surgical removal and radio-chemotherapy, stressing the urgency to find alternative therapies. Several preclinical studies evaluating the anticancer effect of curcumin in animal models of glioma are reported, but a systematic review with meta-analysis of these studies, considering the different experimental conditions used, has not been made up to this date. A search in different databases (Pubmed, Web of Science, Scopus, and SciELO) following the PRISMA statement was conducted during November 2023 to systematically identify articles assessing the effect of curcumin in murine xenograft models of glioma and identified 15 articles, which were subdivided into 24 studies. Tumor volume before and after treatment with curcumin or vehicle was extracted and the efficacy of curcumin was evaluated by performing a random effects meta-analysis of the data. Publication bias and the impact of different experimental conditions on curcumin efficacy were assessed. Treatment with curcumin decreased tumor volume. Comparing curcumin with control groups, the overall weighted standardized difference in means was -2.079 (95% CI: -2.816 to -1.341; p-value < 0.001). The curcumin effect was observed for different animal models, types of glioma cells, administration routes, and curcumin formulations. Publication bias was identified but does not invalidate curcumin's effectiveness. The findings suggest the potential therapeutic efficacy of curcumin against glioma.

MicroRNA-based therapy for glioblastoma: Opportunities and challenges

Glioblastoma (GBM) is the most common and aggressive primary malignant brain tumor and is characterized by high mortality and morbidity rates and unpredictable clinical behavior. The disappointing prognosis for patients with GBM even after surgery and postoperative radiation and chemotherapy has fueled the search for specific targets to provide new insights into the development of modern therapies. MicroRNAs (miRNAs/miRs) act as oncomirs and tumor suppressors to posttranscriptionally regulate the expression of various genes and silence many target genes involved in cell proliferation, the cell cycle, apoptosis, invasion, stem cell behavior, angiogenesis, the microenvironment and chemo- and radiotherapy resistance, which makes them attractive candidates as prognostic biomarkers and therapeutic targets or agents to advance GBM therapeutics. However, one of the major challenges of successful miRNA-based therapy is the need for an effective and safe system to deliver therapeutic compounds to specific tumor cells or tissues in vivo, particularly systems that can cross the blood-brain barrier (BBB). This challenge has shifted gradually as progress has been achieved in identifying novel tumor-related miRNAs and their targets, as well as the development of nanoparticles (NPs) as new carriers to deliver therapeutic compounds. Here, we provide an up-to-date summary (in recent 5 years) of the current knowledge of GBM-related oncomirs, tumor suppressors and microenvironmental miRNAs, with a focus on their potential applications as prognostic biomarkers and therapeutic targets, as well as recent advances in the development of carriers for nontoxic miRNA-based therapy delivery systems and how they can be adapted for therapy.

Depicting the Implication of miR-378a in Cancers

MicroRNA-378a (miR-378a), including miR-378a-3p and miR-378a-5p, are encoded in PPARGC1B gene. miR-378a is essential for tumorigenesis and is an independent prognostic biomarker for various malignant tumors. Aberrant expression of miR-378a affects several physiological and pathological processes, including proliferation, apoptosis, tumorigenesis, cancer invasion, metastasis, and therapeutic resistance. Interestingly, miR-378a has a dual functional role in either promoting or inhibiting tumorigenesis, independent of the cancer type. In this review, we comprehensively summarized the role and regulatory mechanisms of miR-378a in cancer development, hoping to provide a direction for its potential use in cancer therapy.

Intracellular Pathways and Mechanisms of Colored Secondary Metabolites in Cancer Therapy

Despite the great advancements made in cancer treatment, there are still many unsatisfied aspects, such as the wide palette of side effects and the drug resistance. There is an obvious increasing scientific attention towards nature and what it can offer the human race. Natural products can be used to treat many diseases, of which some plant products are currently used to treat cancer. Plants produce secondary metabolites for their signaling mechanisms and natural defense. A variety of plant-derived products have shown promising anticancer properties in vitro and in vivo. Rather than recreating the natural production environment, ongoing studies are currently setting various strategies to significantly manipulate the quantity of anticancer molecules in plants. This review focuses on the recently studied secondary metabolite agents that have shown promising anticancer activity, outlining their potential mechanisms of action and pathways.

Curcumin Sensitises Cancerous Kidney Cells to TRAIL Induced Apoptosis via Let-7C Mediated Deregulation of Cell Cycle Proteins and Cellular Metabolism

Targeted therapies are the most attractive options in the treatment of different tumours, including kidney cancers. Such therapies have entered a golden era due to advancements in research, breakthroughs in scientific knowledge, and a better understanding of cancer therapy mechanisms, which significantly improve the survival rates and life expectancy of patients. The use of tumour necrosis factor (TNF)-related apoptosis inducing ligand (TRAIL) as an anticancer therapy has attracted the attention of the scientific community and created great excitement due to its selectivity in targeting cancerous cells with no toxic impacts on normal tissues. However, clinical studies disappointingly showed the emergence of resistance against TRAIL. This study aimed to employ curcumin to sensitise TRAIL-resistant kidney cancerous ACHN cells, as well as to gain insight into the molecular mechanisms of TRAIL sensitization. Curcumin deregulated the expression of apoptosis-regulating micro Ribonucleic Acid (miRNAs), most notably, let-7C. Transfecting ACHN cells with a let-7C antagomir significantly increased the expression of several cell cycle protein, namely beta (β)-catenin, cyclin dependent kinase (CDK)1/2/4/6 and cyclin B/D. Further, it overexpressed the expression of the two key glycolysis regulating proteins including hypoxia-inducible factor 1-alpha (HIF-1α) and pyruvate dehydrogenase kinase 1 (PDK1). Curcumin also suppressed the expression of the overexpressed proteins when added to the antagomir transfected cells. Overall, curcumin targeted ACHN cell cycle and cellular metabolism by promoting the differential expression of let-7C. To the best of our knowledge, this is the first study to mechanistically report the cancer chemosensitisation potential of curcumin in kidney cancer cells via induction of let-7C.

Review on the Therapeutic Potential of Curcumin and its Derivatives on Glioma Biology

Gliomas are common and aggressive brain tumors that carry a poor prognosis. The current multimodal therapeutic option for glioma includes surgery subsequently temozolomide chemotherapy and/or radiation; but gliomas are often associated with multidrug resistance, intensive adverse events, and tumor relapse. Thus, novel interventions that can enhance successful chemo-prevention and overcome therapeutic resistance are urgently needed. Phytochemicals have several biological properties with multi-target sites and relatively limited degrees of toxicity. Curcumin is a natural polyphenolic compound with several anti-tumor effects which potentially inhibit tumor growth, development, proliferation, invasion, dissemination, and angiogenesis in different human malignancies. Experimental model studies have demonstrated that curcumin attenuates glioma cell viability by G2/M cell cycle arrest, apoptosis, induction of autophagy, gene expression alteration, and disruption of multi-molecular pathways. Moreover, curcumin has been reported to re-sensitize cancer to chemotherapeutics as well as augment the effect of radiotherapy on glioma cells. In this review, we have provided an update on the in vitro and in vivo effects of curcumin-based therapy on gliomas. We have also discussed the use of curcumin in combination therapies, its effectiveness on drug-resistant cells, and new formulations of curcumin in the treatment of gliomas.

Effects of Polyphenols on ncRNAs in cancer - An update

In recent years, oncotherapy has received considerable attention concerning plant polyphenols. Increasing evidence suggests that due to the efficiency of polyphenols, they may have antitumor effects in various cancers. However, their regulatory structures remain elusive. Long non-coding RNAs (LncRNAs) have been identified in the regulation of various forms of tumorigenesis and tumor development. Long non-coding RNAs (LncRNAs) have recently emerged as regulatory eukaryotic transcripts and therapeutic targets with important and diverse functions in health and diseases. LncRNAs may be associated with the initiation, development, and progression of cancer. This review summarizes the research on the modulatory effects of LncRNAs and their roles in mediating cellular processes. The mechanisms of action of polyphenols underlying their therapeutic effects on cancers are also discussed. Based on our review, polyphenols might facilitate a significant epigenetic modification as part of their tissue-/cell-related biological effects. This finding may be attributed to their interaction with cellular signaling pathways involved in chronic diseases. Certain LncRNAs might be the target of specific polyphenols, and some critical signaling processes involved in the intervention of cancers might mediate the therapeutic roles of polyphenols. This article is protected by copyright. All rights reserved.

Natural Plant Compounds: Does Caffeine, Dipotassium Glycyrrhizinate, Curcumin, and Euphol Play Roles as Antitumoral Compounds in Glioblastoma Cell Lines?

Many plant-derived compounds are shown to be promising antitumor therapeutic agents by enhancing apoptosis-related pathways and cell cycle impairment in tumor cells, including glioblastoma (GBM) cell lines. We aimed to review four natural plant compounds effective in GBM cell lines as caffeine, dipotassium glycyrrhizinate (DPG), curcumin, and euphol. Furthermore, antitumoral effect of these plant compounds on GBM cell lines through microRNAs (miRs) modulation was investigated. However, only DPG and curcumin were found as effective on miR modulation. Caffeine arrests GBM cell cycle in G0/G1 phase by cyclin-dependent kinases (CDK) complex inhibition and by decreasing BCL-2 and increasing FOXO1 expression levels causing greater apoptotic activity. Caffeine can also directly inhibit IP3R3, p38 phosphorylation, and rho-associated protein kinase (ROCK), decreasing cell invasion and migration capacity or indirectly by inhibiting the tissue inhibitor metalloproteinase-1 (TIMP-1) and integrins β1 and β3, leading to lower matrix metalloproteinases, MMP-2 and MMP-9. DPG presents antitumoral effect in GBM cells related to nuclear factor kappa B (NF-κB) pathway suppression by IRAK2 and TRAF6-mediating miR-16 and miR-146a, respectively. More recently, it was observed that DPG upregulated miR-4443 and miR-3620, responsible for post-transcriptional inhibition of the NF-κB pathway by CD209 and TNC modulation, respectively leading to lower MMP-9 and migration capacity. Curcumin is able to increase miR-223-3p, miR-133a-3p, miR-181a-5p, miR-34a-5p, miR-30c-5p, and miR-1290 expression leading to serine or threonine kinase (AKT) pathway impairment and also it decreases miR-27a-5p, miR-221-3p, miR-21-5p, miR-125b-5p, and miR-151-3p expression causing p53-BCL2 pathway inhibition and consequently, cellular apoptosis. Interestingly, lower expression of miR-27a by curcumin action enhanced the C/EBP homologous protein(CHOP) expression, leading to paraptosis. Curcumin can inhibit miR-21 expression and consequently activate apoptosis through caspase 3 and death receptor (DR) 4 and 5 activation. Autophagy is controlled by the LC-3 protein that interacts with Atg family for the LC3-II formation and autophagy activation. Euphol can enhance LC3-II levels directly in GBM cells or inhibits tumor invasion and migration through PDK1 modulation.

Natural products in suppressing glioma progression: A focus on the role of microRNAs

Glioma is one of the most common malignancies of the central nervous system. Due to inadequate response to the current treatments available, glioma has been at the center of recent cancer studies searching for novel treatment strategies. This has prompted an intensive search using linkage studies and preliminary evidence to gain efficient insight into the mechanisms involved in the alleviation of the pathogenesis of glioma mediated by miRNAs, a group of noncoding RNAs that affect gene expression posttranscriptionally. Dysregulated expression of miRNAs can exacerbate the malignant features of tumor cells in glioma and other cancers. Natural products can exert anticancer effects on glioma cells by stimulating the expression levels of tumor suppressor miRNAs and repressing the expression levels of oncogenic miRNAs. In this review, we aimed to collect and analyze the literature addressing the roles of natural products in the treatment of glioma, with an emphasis on their involvement in the regulation of miRNAs.

Curcumin in Combination with Other Adjunct Therapies for Brain Tumor Treatment: Existing Knowledge and Blueprint for Future Research

Malignant brain tumors proliferate aggressively and have a debilitating outcome. Surgery followed by chemo-radiotherapy has been the standard procedure of care since 2005 but issues of therapeutic toxicity and relapse still remain unaddressed. Repurposing of drugs to develop novel combinations that can augment existing treatment regimens for brain tumors is the need of the hour. Herein, we discuss studies documenting the use of curcumin as an adjuvant to conventional and alternative therapies for brain tumors. Comprehensive analysis of data suggests that curcumin together with available therapies can generate a synergistic action achieved through multiple molecular targeting, which results in simultaneous inhibition of tumor growth, and reduced treatment-induced toxicity as well as resistance. The review also highlights approaches to increase bioavailability and bioaccumulation of drugs when co-delivered with curcumin using nano-cargos. Despite substantial preclinical work on radio-chemo sensitizing effects of curcumin, to date, there is only a single clinical report on brain tumors. Based on available lab evidence, it is proposed that antibody-conjugated nano-curcumin in combination with sub-toxic doses of conventional or repurposed therapeutics should be designed and tested in clinical studies. This will increase tumor targeting, the bioavailability of the drug combination, reduce therapy resistance, and tumor recurrence through modulation of aberrant signaling cascades; thus improving clinical outcomes in brain malignancies.

The Role of Curcumin in Cancer Treatment

Curcumin is a polyphenol extracted from the rhizomes of the turmeric plant, Curcuma longa which has anti-inflammatory, and anticancer properties. Chronic inflammation is associated with the development of cancer. Curcumin acts on the regulation of various immune modulators, including cytokines, cyclooxygenase-2 (COX-2), and reactive oxygen species (ROS), which partly explains its anticancer effects. It also takes part in the downregulation of growth factors, protein kinases, oncogenic molecules and various signaling pathways, such as nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), c-Jun N-terminal kinase (JNK) and signal transducer and activator of transcription 3 (STAT3) signaling. Clinical trials of curcumin have been completed or are ongoing for various types of cancer. This review presents the molecular mechanisms of curcumin in different types of cancer and the evidence from the most recent clinical trials.

Targeting microRNAs by curcumin: implication for cancer therapy

In spite of all the investigations in the past 20 years that established a great body of knowledge in cancer therapy, utilizing some elderly methods such as plant compound administration might still be useful. Curcumin is a bioactive polyphenol, which has many anticancer properties but its capability in modulating miRNA expression has opened new doors in the field of cancer-targeted therapy. MiRNAs are a class of small noncoding RNAs that are able to regulate gene expression and signaling. In addition, some other effects of these RNAs such as modulating cell differentiation and regulation of cell cycle have made miRNAs great candidates for personalized cancer treatment. In this review, we try to find some answers to the questions on how curcumin exerts its impacts on cancer hallmarks through miRNAs and whether chemotherapy can be replaced by this beneficial plant compound.

Curcumin Regulates Cancer Progression: Focus on ncRNAs and Molecular Signaling Pathways

Curcumin [(1E,6E) ‑1,7‑bis(4‑hydroxy‑3‑methoxyphenyl) hepta‑1,6‑diene‑3,5‑ dione] is a natural polyphenol derived from the rhizome of the turmeric plant Curcuma longa. Accumulated evidences have presented curcumin’s function in terms of anti-inflammatory, antioxidant properties, and especially anti-tumor activities. Studies demonstrated that curcumin could exert anti-tumor activity via multiple biological signaling pathways, such as PI3K/Akt, JAK/STAT, MAPK, Wnt/β-catenin, p53, NF-ĸB and apoptosis related signaling pathways. Moreover, Curcumin can inhibit tumor proliferation, angiogenesis, epithelial-mesenchymal transition (EMT), invasion and metastasis by regulating tumor related non-coding RNA (ncRNA) expression. In this review, we summarized the roles of curcumin in regulating signaling pathways and ncRNAs in different kinds of cancers. We also discussed the regulatory effect of curcumin through inhibiting carcinogenic miRNA and up regulating tumor suppressive miRNA. Furthermore, we aim to illustrate the cross regulatory relationship between ncRNA and signaling pathways, further to get a better understanding of the anti-tumor mechanism of curcumin, thus lay a theoretical foundation for the clinical application of curcumin in the future.

Challenges and Perspectives of Standard Therapy and Drug Development in High-Grade Gliomas

Despite their low incidence rate globally, high-grade gliomas (HGG) remain a fatal primary brain tumor. The recommended therapy often is incapable of resecting the tumor entirely and exclusively targeting the tumor leads to tumor recurrence and dismal prognosis. Additionally, many HGG patients are not well suited for standard therapy and instead, subjected to a palliative approach. HGG tumors are highly infiltrative and the complex tumor microenvironment as well as high tumor heterogeneity often poses the main challenges towards the standard treatment. Therefore, a one-fit-approach may not be suitable for HGG management. Thus, a multimodal approach of standard therapy with immunotherapy, nanomedicine, repurposing of older drugs, use of phytochemicals, and precision medicine may be more advantageous than a single treatment model. This multimodal approach considers the environmental and genetic factors which could affect the patient's response to therapy, thus improving their outcome. This review discusses the current views and advances in potential HGG therapeutic approaches and, aims to bridge the existing knowledge gap that will assist in overcoming challenges in HGG.

The Protective Effect of Polyphenols for Colorectal Cancer

Colorectal cancer (CRC) is one of the most prevalent cancers that threaten people in many countries. It is a multi-factorial chronic disease caused by a combination of genetic and environmental factors, but it is mainly related to lifestyle factors, including diet. Plentiful plant foods and beverages are abundant in polyphenols with antioxidant, anti-atherosclerotic, anti-inflammatory, and anticancer properties. These compounds participate in host nutrition and disease pathology regulation in different ways. Polyphenolic compounds have been used to prevent and inhibit the development and prognosis of cancer, and examples include green tea polyphenol (-)epigallocatechin-3-O-gallate (EGCG), curcumin, and resveratrol. Of course, there are more known and unknown polyphenol compounds that need to be further explored for their anticancer properties. This article focuses on the fact that polyphenols affect the progression of CRC by controlling intestinal inflammation, epigenetics, and the intestinal microbe in the aspects of prevention, treatment, and prognosis.

Therapeutic Potential of Curcumin in the Treatment of Glioblastoma Multiforme

Glioblastoma multiforme (GBM) is the most common primary malignant brain tumor. Despite standard multimodality treatment, the highly aggressive nature of GBM makes it one of the deadliest human malignancies. The anti-cancer effects of dietary phytochemicals like curcumin provide new insights to cancer treatment. Evaluation of curcumin's efficacy against different malignancies including glioblastoma has been a motivational research topic and widely studied during the recent decade. In this review, we discuss the recent observations on the potential therapeutic effects of curcumin against glioblastoma. Curcumin can target multiple signaling pathways involved in developing aggressive and drug-resistant features of glioblastoma, including pathways associated with glioma stem cell activity. Notably, combination therapy with curcumin and chemotherapeutics like temozolomide, the GBM standard therapy, as well as radiotherapy has shown synergistic response, highlighting curcumin's chemo- and radio-sensitizing effect. There are also multiple reports for curcumin nanoformulations and targeted forms showing enhanced therapeutic efficacy and passage through blood-brain barrier, as compared with natural curcumin. Furthermore, in vivo studies have revealed significant anti-tumor effects, decreased tumor size and increased survival with no notable evidence of systemic toxicity in treated animals. Finally, a pharmacokinetic study in patients with GBM has shown a detectable intratumoral concentration, thereby suggesting a potential for curcumin to exert its therapeutic effects in the brain. Despite all the evidence in support of curcumin's potential therapeutic efficacy in GBM, clinical reports are still scarce. More studies are needed to determine the effects of combination therapies with curcumin and importantly to investigate the potential for alleviating chemotherapy- and radiotherapy-induced adverse effects.

Therapeutic potentials of curcumin in the treatment of glioblstoma

Glioblastoma multiforme (GBM), a greatly aggressive malignancy of the brain, is correlated with a poor prognosis and low rate of survival. Up to now, chemotherapy and radiation therapy after surgical approaches have been the treatments increasing the survival rates. The low efficacy of mentioned therapies as well as their side-effects has forced researchers to explore an appropriate alternative or complementary treatment for glioblastoma. In experimental models, it has been shown that curcumin has therapeutic potentials to fight against GBM. Given that curcumin has pharmacological effects against cancer stem cells, as major causes of resistance to therapy in glioblastoma cells. Moreover, it has been showed that curcumin exerts its therapeutic effects on GBM cells via affecting on apoptosis, oxidant system, and inflammatory pathways. Curcumin would possess a synergistic impact with chemotherapeutic agents. Herein, we summarized the current findings on curcumin as therapeutic agent in the treatment of GBM.

The role of dietary phytochemicals in the carcinogenesis via the modulation of miRNA expression

PURPOSE

Phytochemicals are naturally occurring plant-derived compounds and some of them have the potential to serve as anticancer drugs. Based on recent evidence, aberrantly regulated expression of microRNAs (miRNAs) is closely associated with malignancy. MicroRNAs are characterized as small non-coding RNAs functioning as posttranscriptional regulators of gene expression. Accordingly, miRNAs regulate various target genes, some of which are involved in the process of carcinogenesis.

RESULTS

This comprehensive review emphasizes the anticancer potential of phytochemicals, either isolated or in combination, mediated by miRNAs. The ability to modulate the expression of miRNAs demonstrates their importance as regulators of tumorigenesis. Phytochemicals as anticancer agents targeting miRNAs are widely studied in preclinical in vitro and in vivo research. Unfortunately, their anticancer efficacy in targeting miRNAs is less investigated in clinical research.

CONCLUSIONS

Significant anticancer properties of phytochemicals as regulators of miRNA expression have been proven, but more studies investigating their clinical relevance are needed.

Bioactive Ingredients in Chinese Herbal Medicines That Target Non-coding RNAs: Promising New Choices for Disease Treatment

Chinese herbal medicines (CHMs) are widely used in China and have long been a powerful method to treat diseases in Chinese people. Bioactive ingredients are the main components extracted from herbs that have therapeutic properties. Since artemisinin was discovered to inhibit malaria by Nobel laureate Youyou Tu, extracts from natural plants, particularly bioactive ingredients, have aroused increasing attention among medical researchers. The bioactive ingredients of some CHMs have been found to target various non-coding RNA molecules (ncRNAs), especially miRNAs, lncRNAs, and circRNAs, which have emerged as new treatment targets in numerous diseases. Here we review the evidence that, by regulating the expression of ncRNAs, these ingredients exert protective effects, including pro-apoptosis, anti-proliferation and anti-migration, anti-inflammation, anti-atherosclerosis, anti-infection, anti-senescence, and suppression of structural remodeling. Consequently, they have potential as treatment agents in diseases such as cancer, cardiovascular disease, nervous system disease, inflammatory bowel disease, asthma, infectious diseases, and senescence-related diseases. Although research has been relatively limited and inadequate to date, the promising choices and new alternatives offered by bioactive ingredients for the treatment of the above diseases warrant serious investigation.

Curcumin ameliorates atherosclerosis through upregulation of miR-126

The potential usage of curcumin in diverse human diseases has been widely studied, including arteriosclerosis (AS). This study focused on investigating the relationship between curcumin and AS-associated microRNA, which may provide a better understanding of curcumin in a different mechanism. Human microvascular endothelial HMEC-1 cells were treated by curcumin alone or oxidized low-density lipoprotein (ox-LDL) plus curcumin, after which the following parameters were analyzed: cell viability, migration, and the expression of AS-associated factors. The regulatory effects of curcumin on miR-126 and signaling pathways involved in AS were then studied. Further, an animal model of AS was stimulated by feeding rabbits with 1% cholesterol diet. The effects of curcumin on the animal model were explored. We found that curcumin treatment significantly reduced HMEC-1 cells viability, migration, and the protein levels of MMP-2, MMP-9, and vascular endothelial growth factor (VEGF) in the presence or absence of ox-LDL. Meanwhile, the expression of VEGFR1 and VEGFR2 was repressed by curcumin. miR-126 was upregulated by curcumin. The abovementioned effects of curcumin on HMEC-1 cells were all attenuated when miR-126 was silenced. And also, VEGF was a target gene of miR-126, and curcumin could inhibit the activation of PI3K/AKT JAK2/STAT5 signaling pathways via miR-126. The effects of curcumin and its regulation on miR-126 and VEGF were confirmed in the animal model of AS. To sum up, curcumin exerted potent anti-AS property possibly via upregulating miR-126 and thereby inhibiting PI3K/AKT and JAK2/STAT5 signaling pathways.

miR-944 inhibits lung adenocarcinoma tumorigenesis by targeting STAT1 interaction

Lung adenocarcinoma (LAC) is a leading cause of cancer-associated mortalities, particularly in developed countries. The aberrant expression of microRNAs (miRNAs) has been proven to regulate numerous diseases in the past two decades. miRNAs have been identified in almost all human cancer types. In the present study, the role of miR-944 in LAC proliferation was examined. It was identified that miR-944 was downregulated in LAC tissues and cells, and miR-944 overexpression inhibited A549 and H1299 cell proliferation, as determined by the Cell Counting Kit-8 and colony formation assay. Signal transducer and activator of transcription 1 (STAT1) was upregulated in LAC tissues and cells. Kaplan-Meier analysis demonstrated that the 5-year overall survival in patients with high STAT1 levels was significantly reduced, compared with patients with negative and low STAT1 expression. STAT1 was the direct target of miR-944. Additionally, a miR-944 mimic inhibited A549 cell growth in vitro. Collectively, these data demonstrate that miR-944 serves a pivotal role in LAC tumor growth by targeting STAT1. The data obtained indicated that miR-944 may be a novel biomarker and could result in potential therapies for LAC.

Upregulation of microRNA 344a-3p is involved in curcumin induced apoptosis in RT4 schwannoma cells

Background

Schwannoma arising from peripheral nervous sheaths is a benign tumor.

Methods

To evaluate cell cytotoxicity, (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) tetrazolium reduction and terminal deoxynucleotidyltransferase UTP nick-end labeling (TUNEL) assays were used. A microRNA (miRNA) array was used to identify the miRNAs involved in curcumin-induced apoptosis. To examine miRNA expression, quantitative RT-PCR was used.

Results

In this study, curcumin exerted cellular cytotoxicity against RT4 schwannoma cells, with an increase in TUNEL-positive cells. Curcumin also activated the expression of apoptotic proteins, such as polyADP ribose polymerase, caspase-3, and caspase-9. The miRNA array revealed that seven miRNAs (miRNA 350, miRNA 17-2-3p, let 7e-3p, miRNA1224, miRNA 466b-1-3p, miRNA 18a-5p, and miRNA 322-5p) were downregulated following treatment with both 10 and 20 μM curcumin in RT4 cells, while four miRNAs (miRNA122-5p, miRNA 3473, miRNA182, and miRNA344a-3p) were upregulated. Interestingly, transfection with a miRNA 344a-3p mimic downregulated the mRNA expression of Bcl2 and upregulated that of Bax, Curcumin treatment in RT 4 cells also reduced the mRNA expression of Bcl2 and enhanced expression of Bax, Overexpression of miRNA344a-3p mimic combined with curcumin treatment activated the expression of apoptotic proteins, including procaspase-9 and cleaved caspase-3 while inhibition of miRNA 344a-3p using miR344a-3p inhibitor repressed cleaved caspase-3 and -9 in curcumin treated RT-4 cells compared to control.

Conclusions

Our findings demonstrate that curcumin induces apoptosis in schwannoma cells via miRNA 344a-3p. Thus, curcumin may serve as a potent therapeutic agent for the treatment of schwannoma.

MiR‑500a‑5p promotes glioblastoma cell proliferation, migration and invasion by targeting chromodomain helicase DNA binding protein 5

Glioblastoma is one of the most common malignant primary tumors and develops in brain. The molecular mechanism that regulates glioblastoma occurrence still remains unknown. MicroRNA (miR)-500a-5p has been reported to be involved in hepatocellular carcinoma and breast cancer. Whether miR-500a-5p regulates glioblastoma progression requires further investigation. In the present study, miR-500a-5p was highly expressed in malignant glioblastoma tissues and cell lines. Overexpression of miR-500a-5p promoted glioblastoma cell proliferation, migration and invasion in vitro. In addition, knockdown of miR-500a-5p accelerated cell apoptosis. Furthermore, miR-500a-5p inhibition significantly impaired tumor growth in vivo. The present study further explored the downstream mechanism. The luciferase reporter assay revealed that miR-500a-5p directly binds the 3′-untranslated region of chromodomain helicase DNA binding protein 5 (CHD5) mRNA. MiR-500a-5p markedly inhibited CHD5 expression in glioblastoma cells. Furthermore, CHD5 was downregulated in glioblastoma tissues, and the expression levels of miR-500a-5p and CHD5 were inversely correlated. In addition, knockdown of CHD5 restored the inhibition of cell proliferation and migration triggered by miR-500a-5p silence. Finally, it was demonstrated that miR-500a-5p can serve as a novel biomarker for the diagnosis and prognosis of glioblastoma patients. Taken together, the results of the present study indicated that miR-500a-5p may have promoted glioblastoma development and progression by targeting CHD5.

MiR-129 regulates growth and invasion by targeting MAL2 in papillary thyroid carcinoma

MAL2, a member of the MAL proteolipid family, is essential for raft-mediated transport. In this study, we investigated the roles and underlying mechanism of MAL2 in the development of papillary thyroid carcinoma (PTC). Up-regulation of MAL2 was found in human PTC tissues and significantly correlated with poor overall survival (OS). Knockdown of MAL2 dramatically suppressed PTC cell proliferation and invasion in vitro and inhibited tumor growth in vivo. We further found that miR-129 suppressed the expression of MLA through directly binding to the 3' untranslated region (3' UTR). While forced miR-129 expression suppressed growth and invasion of PTC cells, re-expression of MAL2 rescued these effects. Taken together, our data indicated that MAL2 acted as an oncogene and was negatively regulated by miR-129, supporting the potential therapeutic strategy against PTC by targeting miR-129-MAL2 axis.

MiR-192-5p suppresses the growth of bladder cancer cells via targeting Yin Yang 1

Bladder cancer has been identified as one of the most malignant cancers with high incidence and mortality. The underlying mechanisms by which regulate the tumorigenesis of bladder cancer deserve further investigation. Here, we found that miR-192-5p was downregulated in human bladder cancer cell lines and tissues. Overexpression of miR-192-5p significantly inhibited the growth of bladder cancer cells, while depletion of miR-192-5p exerted opposite effect. Bioinformatics analysis and molecular mechanism study identified that miR-192-5p targeted the transcription factor Yin Yang 1 (YY1) and decreased the expression level of YY1. Highly expressed YY1 attenuated the potential tumor suppressive function of miR-192-5p. The expression of miR-192-5p was negatively correlated with that of YY1 in bladder cancer tissues. These results indicated that miR-192-5p might serve as a promising target in bladder cancer diagnosis and therapy.

miR-378 functions as an onco-miRNA by targeting the ST7L/Wnt/β-catenin pathway in cervical cancer

Upregulation or downregulation of microRNAs (miRNAs) has been identified in human cervical cancer (CC). However, the character and function of miR-378 in CC remains unknown. In the present study, the authors demonstrated that miR-378 was upregulated in CC used the reverse transcriptase-quantitative polymerase chain reaction (RT-qPCR) assay, and promoted cell proliferation by accelerating the progress of cell cycle and repressing cell apoptosis in CC cells. The predicted target genes of miR-378 were determined by enhanced green fluorescent protein (EGFP) reporter assays, RT-qPCR assay and western blot analysis. miR-378 suppressed the expression of suppression of tumorigenicity 7-like (ST7L) by targeting the 3′-untranslated region (3′-UTR) of ST7L mRNA in HeLa and SiHa cells. ST7L was downregulated in CC using the RT-qPCR assay, and the malignant phenotype of HeLa and SiHa cells were inhibited by ST7L overexpression. In addition, miR-378 activated the Wnt/β-catenin pathway by targeting ST7L in CC cells. In short, miR-378 functions as an onco-miRNA by directly downregulating ST7L mRNA and protein level in HeLa and SiHa cells, and serves important roles in the malignancy of CC.