Down-regulation of miR-320 associated with cancer progression and cell apoptosis via targeting Mcl-1 in cervical cancer

The role and diagnostic value of deregulated miRNAs in cervical cancer

Cervical cancer (CC) remains a significant global health concern, particularly affecting women in low-income countries. Despite advancements in screening programs, CC continues to pose a substantial mortality risk, highlighting the need to explore diagnostic and treatment modalities. This review focuses on the role of deregulated microRNAs (miRNAs) in CC development, emphasizing their potential as biomarkers for early detection and prognosis in body fluids. miRNAs have emerged as critical regulators of key cellular processes, including proliferation, migration, invasion, and apoptosis, and their dysregulation is closely linked to CC progression. Upregulated miRNAs such as miR-146b-3p, miR-1908, and miR-21 promote CC progression by targeting tumor suppressor genes, while downregulated miRNAs like miR-23-3p and miR-4262 are associated with reduced tumor aggressiveness. miRNAs also hold significant promise as non-invasive prognostic biomarkers. Their expression levels correlate with clinical outcomes, including tumor stage, metastasis, and overall survival, making them valuable tools for risk stratification and personalized treatment strategies. Liquid biopsies, which detect circulating miRNAs in bodily fluids, offer a minimally invasive approach to monitor tumor dynamics and predict patient outcomes. Furthermore, exosomal miRNAs are emerging as promising diagnostic and prognostic tools for CC. Advanced diagnostic technologies and bioinformatics tools are anticipated to enhance the identification of evident miRNA biomarkers in the clinical settings. Standardized protocols for sample collection and analysis will improve the reproducibility of miRNA studies, while a deeper understanding of miRNA biology may unlock their potential as therapeutic targets. In conclusion, this review consolidates current research on deregulated miRNAs in CC, highlighting their diagnostic and prognostic significance. The findings underscore the potential of miRNAs to revolutionize CC management through innovative diagnostic and therapeutic strategies.

To be or not to be: navigating the influence of MicroRNAs on cervical cancer cell death

With all diagnostic and therapeutic advances, such as surgery, radiation- and chemo-therapy, cervical cancer (CC) is still ranked fourth among the most frequent cancers in women globally. New biomarkers and therapeutic targets are warranted to be discovered for the early detection, treatment, and prognosis of CC. As component of the non-coding RNA's family, microRNAs (miRNAs) participate in several cellular functions such as cell proliferation, gene expression, many signaling cascades, apoptosis, angiogenesis, etc. MiRNAs can suppress or induce programmed cell death (PCD) pathways by altering their regulatory genes. Besides, abnormal expression of miRNAs weakens or promotes various signaling pathways associated with PCD, resulting in the development of human diseases such as CC. For that reason, understanding the effects that miRNAs exert on the various modes of tumor PCD, and evaluating the potential of miRNAs to serve as targets for induction of cell death and reappearance of chemotherapy. The current study aims to define the effect that miRNAs exert on cell apoptosis, autophagy, pyroptosis, ferroptosis, and anoikis in cervical cancer to investigate possible targets for cervical cancer therapy. Manipulating the PCD pathways by miRNAs could be considered a primary therapeutic strategy for cervical cancer.

MicroRNA 320a-3p up-regulation reduces PD-L1 expression in gastric cancer cells: an experimental and bioinformatic study

Growing evidence suggests that dysregulated microRNAs were critical in the development of tumors and the progression number of malignancies. This research aimed to check the effect of microRNA 320a-3p transfection on gastric cancer (GC) cell lines. Following transfection, the efficacy was determined by the RT-PCR method. After that, MTT, scratch assay, DAPI staining, RT-PCR, and flow cytometry were used respectively. The results demonstrated that the viability of GC cells considerably decreased following transfection. Moreover, microRNA 320a-3p transfection significantly suppressed cell migration and induced apoptosis in these cells. We found that transfection of microRNA 320a-3p remarkably decreased PD-L1 gene expression and influenced epithelial-mesenchymal transition (EMT)-related and apoptotic gene expressions. The findings propose that microRNA 320a-3p could decrease cell proliferation and migration and induce apoptosis by increasing TP53 and CASP3 expression levels in GC cells. Notably, microRNA 320a-3p might be a potential target in GC immunotherapy by suppressing the PD-L1 gene expression.

miR-4429 inhibits ccRCC proliferation, migration, and invasion by directly targeting CD274

Clear cell renal cell carcinoma (ccRCC) is one of the most aggressive urological malignancies and a highly immunogenic cancer. Yet, its pathogenesis is still not fully understood. This study analyzed the role of the miR-320 family in ccRCC using bioinformatics algorithms and a series of in vitro experiments. miR-4429 was found to be significantly down-regulated in ccRCC tissues and cell lines, while overexpression of miR-4429 significantly inhibited renal cancer cell proliferation, migration, and invasion in vitro. In addition, the UALCAN database, immunohistochemistry, and protein blotting results showed that CD274 expression was up-regulated in ccRCC tissues and correlated with higher histologic grading. Dual luciferase assay indicated that CD274 was a direct target of miR-4429. Overexpression of miR-4429 in 786-O, Caki-2 cells significantly inhibited CD274 expression. KEGG results indicated that the potential target function of miR-4429 was associated with the PI3K/AKT signaling pathway, and protein blotting verified the results. In summary, this data shows that miR-4429 targets CD274 and inhibits ccRCC proliferation, migration, and invasion by regulating PI3K/AKT signaling, thus potentially providing a promising therapeutic target and prognostic biomarker for renal cell carcinoma patients.

Multidimensional outlook on the pathophysiology of cervical cancer invasion and metastasis

Cervical cancer being one of the primary causes of high mortality rates among women is an area of concern, especially with ineffective treatment strategies. Extensive studies are carried out to understand various aspects of cervical cancer initiation, development and progression; however, invasive cervical squamous cell carcinoma has poor outcomes. Moreover, the advanced stages of cervical cancer may involve lymphatic circulation with a high risk of tumor recurrence at distant metastatic sites. Dysregulation of the cervical microbiome by human papillomavirus (HPV) together with immune response modulation and the occurrence of novel mutations that trigger genomic instability causes malignant transformation at the cervix. In this review, we focus on the major risk factors as well as the functionally altered signaling pathways promoting the transformation of cervical intraepithelial neoplasia into invasive squamous cell carcinoma. We further elucidate genetic and epigenetic variations to highlight the complexity of causal factors of cervical cancer as well as the metastatic potential due to the changes in immune response, epigenetic regulation, DNA repair capacity, and cell cycle progression. Our bioinformatics analysis on metastatic and non-metastatic cervical cancer datasets identified various significantly and differentially expressed genes as well as the downregulation of potential tumor suppressor microRNA miR-28-5p. Thus, a comprehensive understanding of the genomic landscape in invasive and metastatic cervical cancer will help in stratifying the patient groups and designing potential therapeutic strategies.

Therapeutic advancements in targeting BCL-2 family proteins by epigenetic regulators, natural, and synthetic agents in cancer

Cancer is amongst the deadliest and most disruptive disorders, having a much higher death rate than other diseases worldwide. Human cancer rates continue to rise, thereby posing the most significant concerns for medical health professionals. In the last two decades, researchers have gone past several milestones in tackling cancer while gaining insight into the role of apoptosis in cancer or targeting various biomarker tools for prognosis and diagnosis. Apoptosis which is still a topic full of complexities, can be controlled considerably by B-cell lymphoma 2 (BCL-2) and its family members. Therefore, targeting proteins of this family to prevent tumorigenesis, is essential to focus on the pharmacological features of the anti-apoptotic and pro-apoptotic members, which will help to develop and manage this disorder. This review deals with the advancements of various epigenetic regulators to target BCL-2 family proteins, including the mechanism of several microRNAs (miRNAs) and long non-coding RNAs (lncRNAs). Similarly, a rise in natural and synthetic molecules' research over the last two decades has allowed us to acquire insights into understanding and managing the transcriptional alterations that have led to apoptosis and treating various neoplastic diseases. Furthermore, several inhibitors targeting anti-apoptotic proteins and inducers or activators targeting pro-apoptotic proteins in preclinical and clinical stages have been summarized. Overall, agonistic and antagonistic mechanisms of BCL-2 family proteins conciliated by epigenetic regulators, natural and synthetic agents have proven to be an excellent choice in developing cancer therapeutics.

Selection of endogenous control and identification of significant microRNA deregulations in cervical cancer

Introduction

Cervical cancer causes approximately 350,000 deaths each year. The availability of sensitive and specific diagnostic tests to detect cervical cancer in its early stages is essential to improve survival rates.

Methods

In this study, we compared two strategies for selecting endogenous controls: miRNA profiling by small-RNA sequencing and a commercially available microfluidic card with 30 recommended endogenous controls preloaded by the manufacturer. We used the RefFinder algorithm and coefficient of variation to select endogenous controls. We selected the combination of miR-181a-5p and miR-423-3p as the most optimal normalizer. In the second part of this study, we determined the differential expression (between tumor/non-tumor groups) of microRNA in cervical cancer FFPE tissue samples. We determined the comprehensive miRNA expression profile using small-RNA sequencing technology and verified the results by real-time PCR. We determined the relative expression of selected miRNAs using the 2^-ΔΔCt method.

Results

We detected statistically significant upregulation of miR-320a-3p, miR-7704, and downregulation of miR-26a-5p in the tumor group compared to the control group. The combination of these miRNAs may have the potential to be utilized as a diagnostic panel for cervical cancer. Using ROC curve analysis, the proposed panel showed 93.33% specificity and 96.97% sensitivity with AUC = 0.985.

Conclusions

We proposed a combination of miR-181a-5p and miR-423-3p as optimal endogenous control and detected potentially significant miRNAs (miR-320a-3p, miR-7704, miR-26a-5p). After further validation of our results, these miRNAs could be used in a diagnostic panel for cervical cancer.

MicroRNA-320-3p promotes the progression of acute pancreatitis by blocking DNMT3a-mediated MMP8 methylation in a targeted manner

In this research, we screened out two genes upregulated in mice with acute pancreatitis (AP) by gene sequencing: microRNA (miR)-320-3p and matrix metalloprotease 8 (MMP8). This study was designed to determine whether miR-320-3p and MMP8 participate in AP development and explore the mechanisms, with a new idea for clinical diagnosis and treatment of AP. Expression of miR-320-3p, DNA methyltransferase 3a (DNMT3a), and MMP8 in mouse pancreatic tissues and AR42J cells was tested by RT-qPCR and western blot assays. Pancreatic pathological changes, serum amylase and lipase, and inflammatory factors in mouse serum and cell supernatant were measured by hematoxylin-eosin staining, automation analyzer, and enzyme-linked immunosorbent assay, respectively. Cell proliferation and apoptosis were determined by CCK-8 assay and flow cytometry. The interaction between miR-320-3p, DNMT3a, and MMP8 was verified by luciferase activity assay, ChIP-qPCR, and MSP assay. High expression of miR-320-3p and MMP8, and low expression of DNMT3a were observed in pancreatic tissues of AP mice and caerulein-induced AP cellular model. Downregulation of miR-320-3p alleviated injury of mouse pancreas, reduced the levels of serum amylase and lipase, and blocked inflammatory factor levels in AP mice. In caerulein-induced AP cellular models, inhibiting miR-320-3p facilitated proliferation and inhibited apoptosis. Upregulation of MMP8 resulted in the opposite results, which could be reversed by simultaneous inhibition of miR-320-3p. miR-320-3p targeted DNMT3a, and downregulating miR-320-3p promoted DNMT3a expression. Moreover, DNMT3a promoted DNA methylation in MMP8 promoter region, thereby inhibiting MMP8 expression in AP mouse and cellular models. This research suggests that miR-320-3p inhibits DNMT3a to reduce MMP8 methylation and increase MMP8 expression, thereby promoting AP progression.

Role of epigallocatechin-3- gallate in the regulation of known and novel microRNAs in breast carcinoma cells

Breast cancer comprises 30% of all cancer cases among the world’s women population. MicroRNAs are small, endogenous, non-coding RNAs that regulate cell proliferating and apoptotic pathways by modulating expressions of related genes. Phytochemicals like epigallocatechin-3-gallate (EGCG) are known to have a chemotherapeutic effect on cancer often through the regulation of microRNAs. The aim is to find out the key known and novel miRNAs, which are controlled by EGCG in breast cancer cell line MDA-MB-231. Next-generation sequencing (NGS) revealed 1,258 known and 330 novel miRNAs from untreated and 83 μM EGCG (IC50 value of EGCG) treated cells. EGCG modulated 873 known and 47 novel miRNAs in the control vs. treated sample. The hypothesis of EGCG being a great modulator of miRNAs that significantly control important cancer-causing pathways has been established by analyzing with Kyoto Encyclopedia of Genes and Genomes (KEGG) and Protein Analysis Through Evolutionary Relationships (PANTHER) database. Validation of known and novel miRNA expression differences in untreated vs. treated cells was done using qPCR. From this study, a few notable miRNAs were distinguished that can be used as diagnostics as well as prognostic markers for breast cancer.

Understanding MCL1: from cellular function and regulation to pharmacological inhibition

Myeloid cell leukemia-1 (MCL1), an antiapoptotic member of the BCL2 family characterized by a short half-life, functions as a rapid sensor that regulates cell death and other relevant processes that include cell cycle progression and mitochondrial homeostasis. In cancer, MCL1 overexpression contributes to cell survival and resistance to diverse chemotherapeutic agents; for this reason, several MCL1 inhibitors are currently under preclinical and clinical development for cancer treatment. However, the nonapoptotic functions of MCL1 may influence their therapeutic potential. Overall, the complexity of MCL1 regulation and function represent challenges to the clinical application of MCL1 inhibitors. We now summarize the current knowledge regarding MCL1 structure, regulation, and function that could impact the clinical success of MCL1 inhibitors.

Tumor pH-functionalized and charge-tunable nanoparticles for the nucleus/cytoplasm-directed delivery of oxaliplatin and miRNA in the treatment of head and neck cancer

Prospective tumor pH-responsive and charge-convertible nanoparticles have been utilized to reduce side effects and improve the active tumor-targeting ability and nuclear/cytoplasmic localization of chemo- and gene therapeutics for the treatment of head and neck cancer (HNC). Oxaliplatin (Oxa) is a third-generation platinum compound that prevents DNA replication. miR-320 may regulate cancer cell apoptosis, resistance, and progression. Innovative nanoparticles incorporating miR-320 and Oxa were modified with a ligand, cell-penetrating peptide, and nucleus-targeted peptide. The nanoparticles were coated with a charge/size-tunable shield to prevent peptide degradation and decoated at acidic tumor sites to expose peptides for active targeting. Results indicated that the designed nanoparticles exhibited a uniform size and satisfactory drug encapsulation efficiency. The nanoparticles displayed the pH-responsive release and uptake of Oxa and miR-320 into human tongue squamous carcinoma SAS cells. The nanoparticles successfully delivered Oxa and miR-320 to the nucleus and cytoplasm, respectively. This work is the first to demonstrate the concurrent intracellular modulation of the NRP1/Rac1, PI3K/Akt/mTOR, GSK-3β/FOXM1/β-catenin, P-gp/MRPs, KRAS/Erk/Oct4/Yap1, and N-cadherin/Vimentin/Slug pathways to inhibit the growth, progression, and multidrug resistance of cancer cells. In SAS-bearing mice, co-treatment with Oxa- and miR-320-loaded nanoparticles exhibited superior antitumor efficacy and remarkably decreased Oxa-associated toxicities. The nucleus/cytoplasm-localized nanoparticles with a tumor pH-sensitive and size/charge-adjustable coating may be a useful combinatorial spatiotemporal nanoplatform for nucleic acids and chemotherapeutics to achieve maximum therapeutic safety and efficacy against HNC. STATEMENT OF SIGNIFICANCE: Innovative nanoparticles incorporating miR-320 and oxaliplatin were modified with a ligand, cell-penetrating peptide, and nucleus-targeted peptide. The tumor pH-sensitive and charge/size-adjustable shield of polyglutamic acid-PEG protected against peptide degradation during systemic circulation. This work represents the first example of the concurrent intracellular modulation of the NRP1/Rac1, PI3K/Akt/mTOR, GSK-3β/FOXM1/β-catenin, P-gp/MRPs, KRAS/Erk/Oct4/Yap1, and N-cadherin/Vimentin/Slug pathways to inhibit cancer cell growth, cancer cell progression, and multidrug resistance simultaneously. The versatile nanoparticles with a tumor pH-functionalized coating could deliver chemotherapeutics and miRNA to the nucleus/cytoplasm. The nanoparticles successfully reduced chemotherapy-associated toxicities and maximized the antitumor efficacy of combinatorial therapy against head and neck cancer.

Role of Phosphatidylinositol 3-Kinase and Its Catalytic Unit PIK3CA in Cervical Cancer: A Mini-Review

In complicated disorders like cancer, signaling pathways form a tangled network. Targeting one gene may result in an unfavorable reaction from another off-target gene. Such entwined complexities may result in treatment resistance or failure in cancer patients. The PI3K/Akt/mTOR (phosphoinositol 3-kinase/protein kinase B/mammalian target of rapamycin) pathway is dysregulated in cervical cancer and is used as a biomarker for therapy. PI3K is a kinase that consists of a regulatory and catalytic domain and has phosphorylation capability. Class I components like the catalytic part (PIK3CA and PIK3CD) and regulatory part (like PIK3R1, PIK3R2, PIK3R3, and PIK3R5) are associated with oncogenesis and growth factors in cervical cancer. This review is aimed at discussing the involvement of the PI3K component of the PI3K/Akt/mTOR network in cervical cancer. Specifically, class I catalytic subunit PIK3CA has been identified as a pharmacological target, making it therapeutically significant. Apart from discussing the function of PI3K and PIK3CA in cervical cancer, we also discuss their inhibitors, which may be beneficial in treating cervical cancer.

Protective Effect of miR-193a-5p and miR-320-5p on Caerulein-Induced Injury in AR42J Cells

BACKGROUND

Acute pancreatitis is a common inflammatory disease. MicroRNAs have been implicated in the pathogenesis of acute pancreatitis.

AIMS

The purpose of this study was to investigate the precise roles of miR-193a-5p and miR-320-5p in AP.

METHODS

The levels of miR-193a-5p, miR-320-5p and tumor necrosis factor receptor-associated factor 3 were detected by quantitative real-time polymerase chain reaction. Cell apoptosis was determined using flow cytometry. Enzyme-linked immunosorbent assay was performed to measure TNF-α, IL-6, IL-1β and IL-8 production, amylase activity, and malondialdehyde content. Targeted relationship between miR-193a-5p or miR-320-5p and TRAF3 was confirmed by the dual-luciferase reporter and RNA immunoprecipitation assays.

RESULTS

Our data showed that miR-193a-5p and miR-320-5p were down-regulated in acute pancreatitis serum and caerulein-treated AR42J cells. The increased expression of miR-193a-5p or miR-320-5p alleviated caerulein-induced cell injury in AR42J cells. Tumor necrosis factor receptor-associated factor 3 was a direct target of miR-193a-5p and miR-320-5p in AR42J cells. Moreover, miR-193a-5p and miR-320-5p regulated caerulein-induced AR42J cells injury through targeting tumor necrosis factor receptor-associated factor 3.

CONCLUSION

The present findings demonstrated that miR-193a-5p and miR-320-5p protected AR42J cells against caerulein-induced cell injury by targeting tumor necrosis factor receptor-associated factor 3, highlighting their roles as potential therapeutic targets for acute pancreatitis treatment.

Role of miRNAs in cervical cancer: A comprehensive novel approach from pathogenesis to therapy

Human papillomaviruses (HPV) infection is a major causative agent and strongly associated with the development of cervical cancer. Understanding the mechanisms of HPV-induced cervical cancer is extremely useful in therapeutic strategies for primary prevention (HPV vaccines) and secondary prevention (screening and diagnosis of precancerous lesions). However, due to the lack of proper implementation of screening programs in developing countries, cervical cancer is usually diagnosed at advanced stages that result in poor treatment responses. Nearly half of the patients will experience disease recurrence within two years post treatment. Therefore, it is vital to identify new tools for early diagnosis, prognosis, and treatment prediction. MicroRNAs (miRNAs) are small non-coding RNAs, implicated in posttranscriptional regulation of gene expression. Growing evidence has shown that abnormal miRNA expression is associated with cervical cancer progression, metastasis, and influences treatment outcomes. In this review, we provide comprehensive information about miRNA and their potential utility in cervical cancer diagnosis, prognosis, and clinical management to improve patient outcomes.

LncRNA NLIPMT Inhibits Tumorigenesis in Esophageal Squamous-Cell Carcinomas by Regulating miR-320/Survivin Axis

Background

LncRNA has been widely investigated for decades and plays critical roles in the progression of cancer. However, lncRNA NLIPMT, as a novel non-coding RNA, only was studied in breast cancer. This study aimed to explore the role of NLIPMT in esophageal squamous-cell carcinomas (ESCC).

Materials and Methods

NLIPMT, miR320 and survivin mRNA in ESCC tissues (or non-tumor tissue) were detected by qRT-PCR. Dual-luciferase reporter assay was performed to assess the relationship between miR-320 and survivin. In ESCC cell lines KYSE510 and ECA109, miR-320 mimic and expression vectors carrying NLIPMT and survivin were used. Cell cycle, apoptosis, proliferation and migration were detected by flow cytometry, CCK-8, transwell assay, respectively. NIPMT, miR-320 and survivin expression were measured by qRT-PCR and Western blotting.

Results

NLIPMT was downregulated in ESCC and predicted poor survival of ESCC patients. NLIPMT was positively correlated with miR-320 and negatively correlated with survivin in ESCC tumor tissues. Dual-luciferase reporter assay showed that miR-320 directly regulated survivin. qRT-PCR and Western blotting showed that NLIPMT promoted miR-320 expression and inhibited survivin expression via up-regulating miR-320. Moreover, both NLIPMT and miR-320 overexpression inhibited cell proliferation and migration and promoted cell cycle arrest and apoptosis in ESCC cells, while their effects were abolished by survivin overexpression.

Conclusion

We demonstrate that NLIPMT inhibits cell proliferation and migration and promotes cell cycle arrest and apoptosis in ESCC cells by regulating the miR-320/survivin axis. NLIPMT may be a novel prognosis biomarker in ESCC patients.

The Emerging Role of MicroRNAs in Regulating the Drug Response of Cholangiocarcinoma

Cholangiocarcinoma (CCA) is the most common biliary malignancy, and has a poor prognosis. The median overall survival with the standard-of-care chemotherapy (Gemcitabine and cisplatin) in patients with advanced-stage CCA is less than one year. The limited efficacy of chemotherapy or targeted therapy remains a major obstacle to improving survival. The mechanisms involved in drug resistance are complex. Research efforts focusing on the distinct molecular mechanisms underlying drug resistance should prompt the development of treatment strategies that overcome chemoresistance or targeted drug resistance. MicroRNAs (miRNAs) are a class of evolutionarily conserved, short noncoding RNAs regulating gene expression at the post-transcriptional level. Dysregulated miRNAs have been shown to participate in almost all CCA hallmarks, including cell proliferation, migration and invasion, apoptosis, and the epithelial-to-mesenchymal transition. Emerging evidence demonstrates that miRNAs play a role in regulating responses to chemotherapy and targeted therapy. Herein, we present an overview of the current knowledge on the miRNA-mediated regulatory mechanisms underlying drug resistance among CCA. We also discuss the application of miRNA-based therapeutics to CCA, providing the basis for innovative treatment approaches.

The roles of microRNA in human cervical cancer

Although a potentially preventable disease, cervical cancer (CC) is the second most commonly diagnosed gynaecological cancer with at least 530,000 new cases annually, and the prognosis with CC is still poor. Studies suggest that aberrant expression of microRNA (miRNA) contributes to the progression of CC. As a group of small non-coding RNA with 18-25 nucleotides, miRNA regulate about one-third of all human genes. They function by repressing translation or inducing mRNA cleavage or degradation, including genes involved in diverse and important cellular processes, including cell cycling, proliferation, differentiation, and apoptosis. Results showed that misexpression of miRNA is closely related to the onset and progression of CC. This review will provide an overview of the function of miRNA in CC and the mechanisms involved in cervical carcinogenesis.

Noncoding RNAs: the shot callers in tumor immune escape

Immunotherapy, designed to exploit the functions of the host immune system against tumors, has shown considerable potential against several malignancies. However, the utility of immunotherapy is heavily limited due to the low response rate and various side effects in the clinical setting. Immune escape of tumor cells may be a critical reason for such low response rates. Noncoding RNAs (ncRNAs) have been identified as key regulatory factors in tumors and the immune system. Consequently, ncRNAs show promise as targets to improve the efficacy of immunotherapy in tumors. However, the relationship between ncRNAs and tumor immune escape (TIE) has not yet been comprehensively summarized. In this review, we provide a detailed account of the current knowledge on ncRNAs associated with TIE and their potential roles in tumor growth and survival mechanisms. This review bridges the gap between ncRNAs and TIE and broadens our understanding of their relationship, providing new insights and strategies to improve immunotherapy response rates by specifically targeting the ncRNAs involved in TIE.

miR‑320‑3p is involved in morphine pre‑conditioning to protect rat cardiomyocytes from ischemia/reperfusion injury through targeting Akt3

Morphine pre-conditioning (MPC) can significantly reduce myocardial ischemic injury and inhibit cardiomyocyte apoptosis, but the underlying mechanism still remains unclear. The aim of the present study was to investigate the protective mechanism of MPC in myocardial hypoxia/reoxygenation (H/R) injury at the microRNA (miR) level. H9c2 cells were used as a model of H/R and subjected to morphine pre-treatment. The protective effects of MPC on H/R injury in cardiomyocytes were evaluated using MTT and colorimetric assay, as well as flow cytometry. In addition, reverse transcription-quantitative PCR, western blotting and dual-luciferase reporter assay experiments were performed to determine the relationship between MPC, miR-320-3p and Akt3, and their effects on H/R injury. The present study demonstrated that MPC enhanced cell activity, decreased LDH content, and reduced apoptosis in rat cardiomyocytes, suggesting that MPC could protect these cells from H/R injury. Moreover, MPC partially reversed the increase in miR-320-3p expression and the decrease in Akt3 levels caused by H/R injury. Inhibition of miR-320-3p expression also attenuated the effects of H/R on cardiomyocyte activity, LDH content and apoptosis. Furthermore, Akt3 was predicted to be a target gene of miR-320-3p, and overexpression of miR-320-3p inhibited the expression of Akt3, blocking the protective effects of MPC on the cells. The current findings revealed that MPC could protect cardiomyocytes from H/R damage through targeting miR-320-3p to regulate the PI3K/Akt3 signaling pathway.

Tumor-associated exosomal miRNA biomarkers to differentiate metastatic vs. nonmetastatic non-small cell lung cancer

Background

Exosomal microRNAs (miRNAs) are proposed to be excellent candidate biomarkers for clinical applications. However, little is known about their potential value as diagnostic biomarkers for metastatic non-small cell lung cancer (NSCLC).

Methods

In this study, microarrays were used to determine distinct miRNA profiles of plasma exosomes in a discovery cohort of healthy donors, metastatic NSCLC and nonmetastatic NSCLC patients. Three potential candidate miRNAs were selected based on the differential expression profiles. The discovery set data were validated by quantitative real-time polymerase chain reaction using a validation cohort.

Results

NSCLC patients (n = 80) and healthy controls (n = 30) had different exosome-related miRNA profiles in plasma. Results demonstrated that the level of let-7f-5p was decreased in plasma exosomes of NSCLC patients (p < 0.0001). Further analysis of three differentially expressed miRNAs revealed that miR-320a, miR-622 and let-7f-5p levels could significantly segregate patients with metastatic NSCLC from patients with nonmetastatic NSCLC (p < 0.0001, p < 0.0001 and p = 0.023, respectively). In addition, the combination of let-7f-5p, CEA and Cyfra21-1 generated an area under the curve (AUC) of 0.981 for the diagnosis of NSCLC patients, and the combination of miR-320a, miR-622, CEA and Cyfra21-1 had an AUC of 0.900 for the diagnosis of patients with metastatic NSCLC.

Conclusions

This novel study demonstrated that plasma exosomal miRNAs are promising noninvasive diagnostic biomarkers for metastatic NSCLC.

Edaravone reduces oxidative stress and intestinal cell apoptosis after burn through up-regulating miR-320 expression

BACKGROUND

Intestinal mucosa barrier dysfunction after burn injury is an important factor for causing mortality of burn patients. The current study established a burn model in rats and used a free radical scavenger edaravone (ED) to treat the rats, so as to investigate the effect of edaravone on intestinal mucosa barrier after burn injury.

METHODS

Anesthetized rats were subjected to 40% total body surface area water burn immediately, followed by treatment with ED, scrambled antagomir, or antagomiR-320. Intestinal mucosa damage was observed by hematoxylin-eosin staining and graded by colon mucosal damage index (CMDI) score. The contents of total sulfhydryl (TSH), superoxide dismutase (SOD), catalase (CAT) and malondialdehyde (MDA) were determined by spectrophotometry. Cell apoptosis, protein relative expression,and the in situ expressions of p-Akt and p-Bad were detected by flow cytometry, Western blotting and immunohistochemistry, respectively. The miR-320 expression was determined by quantitative real-time polymerase chain reaction.

RESULTS

ED alleviated intestinal mucosal damage caused by burn injury, down-regulated the levels of MDA, cytochrome C, cleaved caspase-9 and cleaved caspase-3, but up-regulated the levels of TSH, SOD, CAT and Bcl-2. We also found that ED could reduce oxidative stress, inhibit cell apoptosis, increase the expressions of p-Akt, p-Bad and miR-320, and decrease PTEN expression. PTEN was predicted to be the target gene for miR-320, and cell apoptosis could be promoted by inhibiting miR-320 expression.

CONCLUSION

ED regulates Akt/Bad/Caspase signaling cascade to reduce apoptosis and oxidative stress through up-regulating miR-320 expression and down-regulating PTEN expression, thus protecting the intestinal mucosal barrier of rats from burn injury.

LncRNA ANRIL protects against oxygen and glucose deprivation (OGD)-induced injury in PC-12 cells: potential role in ischaemic stroke

lncRNA ANRIL was reported to be closely related to ischaemic stroke (IS). In this study, we used oxygen-glucose deprivation (OGD) to stimulate rat adrenal medulla-derived pheochromocytoma cell line PC-12 to construct an in vitro IS cell model and investigated the role of ANRIL and the underlying mechanism. PC-12 cells were stimulated by OGD and/or transfected with pc-ANRIL, si-ANRIL, miR-127 mimic, miR-127 inhibitor, pEX-Mcl-1, sh-Mcl-1 and their negative controls. Cell viability, apoptosis, mRNA and protein expression was detected using CCK-8 assay, flow cytometry assay, qRT-PCR and western blot, respectively. Results showed that OGD-induced PC-12 cell injury and decreased ANRIL expression. ANRIL overexpression significantly reduced OGD-induced PC-12 cell injury evidenced by increasing cell viability and decreasing apoptosis, while ANRIL silence led to the opposite results. Meanwhile, dysregulation of ANRIL altered the expression of apoptotic proteins. Furthermore, ANRIL negatively regulated miR-127 expression. miR-127 overexpression significantly enhanced OGD-induced PC-12 cell injury. In addition, Mcl-1 expression was negatively regulated by miR-127, besides ANRIL up-regulated Mcl-1 expression by down-regulation of miR-127. Mcl-1 overexpression alleviated cell injury and miR-127 silence up-regulated Mcl-1 expression. In conclusion, lncRNA ANRIL alleviated OGD-induced PC-12 cell injury as evidenced. PI3K/AKT pathway might be involved in this regulating progression.

Role of MicroRNAs in Treatment Response in Prostate Cancer

Prostate cancer (PCa) is the most common non-skin cancer in men worldwide, resulting in significant mortality and morbidity. Depending on the grade and stage of the cancer, patients may be given radiation therapy, hormonal therapy, or chemotherapy. However, more than half of these patients develop resistance to treatment, leading to disease progression and metastases, often with lethal consequences. MicroRNAs (miRNAs) are short, non-coding RNAs, which regulate numerous physiological as well as pathological processes, including cancer. miRNAs mediate their regulatory effect predominately by binding to the 3'-untranslated region (UTR) of their target mRNAs. In this review, we will describe the mechanisms by which miRNAs mediate resistance to radiation and drug therapy (i.e. hormone therapy and chemotherapy) in PCa, including control of apoptosis, cell growth and proliferation, autophagy, epithelial-to-mesenchymal transition (EMT), invasion and metastasis, and cancer stem cells (CSCs). Furthermore, we will discuss the utility of circulating miRNAs isolated from different body fluids of prostate cancer patients as non-invasive biomarkers of cancer detection, disease progression, and therapy response. Finally, we will shortlist the candidate miRNAs, which may have a role in drug and radioresistance, that could potentially be used as predictive biomarkers of treatment response.

MicroRNAs in cancer cell death pathways: Apoptosis and necroptosis

To protect tissues and the organism from disease, potentially harmful cells are removed through programmed cell death processes, including apoptosis and necroptosis. These types of cell death are critically controlled by microRNAs (miRNAs). MiRNAs are short RNA molecules that target and inhibit expression of many cellular regulators, including those controlling programmed cell death via the intrinsic (Bcl-2 and Mcl-1), extrinsic (TRAIL and Fas), p53-and endoplasmic reticulum (ER) stress-induced apoptotic pathways, as well as the necroptosis cell death pathway. In this review, we discuss the current knowledge of apoptosis and necroptosis pathways and how these are impaired in cancer cells. We focus on how miRNAs disrupt apoptosis and necroptosis, thereby critically contributing to malignancy. Understanding which and how miRNAs and their targets affect cell death pathways could open up novel therapeutic opportunities for cancer patients. Indeed, restoration of pro-apoptotic tumor suppressor miRNAs (apoptomiRs) or inhibition of oncogenic miRNAs (oncomiRs) represent strategies that are currently being trialed or are already applied as miRNA-based cancer therapies. Therefore, better understanding the cancer type-specific expression of apoptomiRs and oncomiRs and their underlying mechanisms in cell death pathways will not only advance our knowledge, but also continue to provide new opportunities to treat cancer.

lncRNA ATXN8OS promotes breast cancer by sequestering miR‑204

Breast cancer (BC) is a common malignancy among women and the leading cause of female cancer mortality worldwide. In recent years, increasing evidence has shown that long non-coding RNAs (lncRNAs) can act as competing endogenous RNAs (ceRNAs) in human cancer and that they are involved in many biological processes, including proliferation, migration, apoptosis and invasion. In the present study, the biological function and molecular mechanism of ataxin 8 opposite strand (ATXN8OS) in BC tissue and cell lines were investigated. It was found that ATXN8OS was markedly up-regulated in BC tissue and cell lines, and that its level of overexpression was inversely linked with the overall survival rate of patients with BC. Knockdown of ATXN8OS inhibited proliferation, viability and invasion in the human MCF7 and MDA-MB-231 BC cell lines. In addition, microRNA-204 (miR-204) was negatively associated with the expression of ATXN8OS in BC tissues and cell lines. A luciferase assay demonstrated a direct binding site for miR-204 within ATXN8OS, and inhibition of miR-204 stimulated the tumour-promoting effect of ATXN8OS on BC cells. In conclusion, the present study suggested that ATXN8OS acts as a tumour promoter by sequestering miR-204 during the development of BC, therefore providing a mechanistic insight which may facilitate the diagnosis and treatment of BC.

Expression of TMEFF2 in Human Pancreatic Cancer Tissue and the Effects of TMEFF2 Knockdown on Cell, Proliferation, and Apoptosis in Human Pancreatic Cell Lines

Background

The TMEFF2 gene encodes the transmembrane protein with EGF like and two follistatin-like domains 2 and has been reported to be a tumor suppressor gene, but its role remains unknown in pancreatic cancer. This study aimed to investigate the expression of TMEFF2 in human pancreatic cancer tissue and the effects of knockdown of TMEFF2 on cell, proliferation, and apoptosis in human pancreatic cell lines.

Material/Methods

Thirty-five samples of human pancreatic tissue and adjacent normal pancreatic tissue, and five human pancreatic cancer cell lines, CAPAN1, ASPC1, BXPC3, SW1990, and CFPAC were studied. RNA expression, protein expression, cell proliferation, and apoptosis were studied using real-time polymerase chain reaction (RT-PCR), Western blot, the cell counting kit-8 (CCK-8) assay, and flow cytometry, respectively. A co-immunoprecipitation assay evaluated protein interactions.

Results

TMEFF2 expression was down-regulated in pancreatic cancer tissue compared with normal pancreas. In human pancreatic cancer cell lines, overexpression of TMEFF2 suppressed cell proliferation and enhanced apoptosis, suppressed the expression of p-STAT3, MCL1, VEGF and increased the expression of the tyrosine-specific protein phosphatase, SHP-1. The co-immunoprecipitation assay showed that TMEFF2 interacted with SHP-1. Knockdown of expression of TMEFF2 resulted in the increased expression of p-STAT3, MCL1, and VEGF, increased cell proliferation and decreased cell apoptosis, which were reversed by overexpression of SHP-1.

Conclusions

In pancreatic cancer, TMEFF2 exerted as a tumor suppressor effect by regulating p-STAT3, MCL1, and VEGF via SHP-1.

Upregulation of long non-coding RNA NNT-AS1 promotes osteosarcoma progression by inhibiting the tumor suppressive miR-320a

OBJECTIVE

To investigate the role and mechanism of action of nicotinamide nucleotide transhydrogenase antisense RNA 1 (NNT-AS1) in osteosarcoma (OS).

METHODS

Bioinformatic analysis suggested miR-320a as potential target of NNT-AS1. Influence of NNT-AS1 overexpression or knockdown on OS cell proliferation, colony-formation, apoptosis, migration and invasion capacity was first investigated. Expression levels of NNT-AS1, miR-320a, beta-catenin, RUNX2, IGF-1R, c-Myc, Cyclin D1 and MMP13 were also evaluated by RT-qPCR and western blotting accordingly. Xenograft models using U2OS and OS-732 cells with different NNT-AS1 gene modifications were constructed for tumor formation assay as well as evaluation of miR-320a, beta-catenin and RUNX2 expression in primary lesion. NNT-AS1-overexpressing U2OS cells and NNT-AS1-knockdown OS-732 cells were subject to miR-320a mimic and inhibitor transfection, respectively, to investigate the miR-320a dependency of the osteosarcoma-promoting role of NNT-AS1.

RESULTS

NNT-AS1 overexpression significantly increased proliferation, survival and mobility of U2OS cells in vitro as well as its tumor formation ability in vivo, while NNT-AS1 knockdown showed opposite effect on OS-732 cells. In both in vitro and in vivo model, NNT-AS1 expression level significantly correlated with that of beta-catenin, RUNX2, IGF-1R, c-Myc, Cyclin D1 and MMP13 as well as Akt phosphorylation level, and inversely correlated with miR-320a expression. Transfection of miR-320a mimic significantly inhibiter the promoting effect of NNT-AS1 on cell proliferation, survival and mobility of U2OS cells, while miR-320 inhibitor partially rescued that of OS-732 cells.

CONCLUSION

NNT-As1 functions as a cancer-promoting lncRNA by downregulating miR-320a, thus increasing the protein expression level of beta-catenin, RUNX2 and IGF-1R as well as activation of Akt in osteosarcoma.

Oncogenic and Tumor-Suppressive Roles of MicroRNAs with Special Reference to Apoptosis: Molecular Mechanisms and Therapeutic Potential

MicroRNAs (miRNAs) are the non-coding class of minute RNA molecules that negatively control post-transcriptional regulation of various functional genes. These miRNAs are transcribed from the loci present in the introns of functional or protein-coding genes, exons of non-coding genes, or even in the 3'-untranslated region (3'-UTR). They have potential to modulate the stability or translational efficiency of a variety of target RNA [messenger RNA (mRNA)]. The regulatory function of miRNAs has been elucidated in several pathological conditions, including neurological (Alzheimer's disease and Parkinson's disease) and cardiovascular conditions, along with cancer. Importantly, miRNA identification in cancer progression and invasion has evolved as an incipient era in cancer treatment. Several studies have shown the influence of miRNAs on various cancer processes, including apoptosis, invasion, metastasis and angiogenesis. In particular, apoptosis induction in tumor cells through miRNA has been extensively studied. The biphasic mode (up- and down-regulation) of miRNA expression in apoptosis and other cancer processes has already been determined. The findings of these studies could be utilized to develop potential therapeutic strategies for the management of various cancers. The present review critically describes the oncogenic and tumor suppressor role of miRNAs in apoptosis and other cancer processes, therapy resistance, and use of their presence in the body fluids as biomarkers.

Decreased miR-320 expression is associated with breast cancer progression, cell migration, and invasiveness via targeting Aquaporin 1

Our previous studies have demonstrated that Aquaporin 1 (AQP1) is overexpressed in breast cancer. However, the mechanism remains elusive. MicroRNA 320 (miR-320) downregulation has been reported in various types of cancers, and it may regulate AQP1 expression. In this study, miR-320 and AQP1 expressions were investigated by quantitative reverse transcription-PCR, in situ hybridization, and immunohistochemistry. The clinicopathological implications of these molecules were also analyzed. We found that miR-320 expression is downregulated in both plasma and tumor tissue in human breast cancer patients. Survival analysis showed that reduced expression of miR-320 and overexpression of AQP1 are associated with worse prognosis. Luciferase assays showed that miR-320 negatively regulates AQP1 expression. In addition, cell proliferation, migration, and invasion assays were performed to investigate the effects of miR-320 on breast cancer cells. Our results showed that miR-320 overexpression inhibits cell proliferation, migration, and invasion in breast cancer cells by downregulating AQP1. These observations suggested that miR-320 downregulation may enhance AQP1 expression in breast cancer, favoring tumor progression. Our findings indicated that miR-320 and AQP1 may serve as prognostic biomarkers and therapeutic targets in the treatment of breast cancer.

MiR-320 regulates cardiomyocyte apoptosis induced by ischemia-reperfusion injury by targeting AKIP1

Background

MicroRNAs play important roles in regulation of the cardiovascular system. The purpose of this study was to investigate microRNA-320 (miR-320) expression in myocardial ischemia-reperfusion (I/R) injury and the roles of miR-320 in cardiomyocyte apoptosis by targeting AKIP1 (A kinase interacting protein 1).

Methods

The level of miR-320 was detected using quantitative real-time polymerase chain reaction (qRT-PCR), and cardiomyocyte apoptosis was detected via terminal dUTP nick end-labeling assay. Cardiomyocyte apoptosis and the mitochondrial membrane potential were evaluated via flow cytometry. Bioinformatics tools were used to identify the target gene of miR-320. The expression levels of AKIP1 mRNA and protein were detected via qRT-PCR and Western blot, respectively.

Results

Both the level of miR-320 and the rate of cardiomyocyte apoptosis were substantially higher in the I/R group and H9c2 cells subjected to H/R than in the corresponding controls. Overexpression of miR-320 significantly promoted cardiomyocyte apoptosis and increased the loss of the mitochondrial membrane potential, whereas downregulation of miR-320 had an opposite effect. Luciferase reporter assay showed that miR-320 directly targets AKIP1. Moreover, knock down and overexpression of AKIP1 had similar effects on the H9c2 cells subjected to H/R.

Conclusions

miR-320 plays an important role in regulating cardiomyocyte apoptosis induced by I/R injury by targeting AKIP1 and inducing the mitochondrial apoptotic pathway.

MicroRNA-focused CRISPR-Cas9 library screen reveals fitness-associated miRNAs

MicroRNAs (miRNAs) are post-transcriptional gene regulators that play important roles in the control of cell fitness, differentiation, and development. The CRISPR-Cas9 gene-editing system is composed of the Cas9 nuclease in complex with a single guide RNA (sgRNA) and directs DNA cleavage at a predetermined site. Several CRISPR-Cas9 libraries have been constructed for genome-scale knockout screens of protein function; however, few libraries have included miRNA genes. Here we constructed a miRNA-focused CRISPR-Cas9 library that targets 1594 (85%) annotated human miRNA stem-loops. The sgRNAs in our LX-miR library are designed to have high on-target and low off-target activity, and each miRNA is targeted by four to five sgRNAs. We used this sgRNA library to screen for miRNAs that affect cell fitness of HeLa or NCI-N87 cells by monitoring the change in frequency of each sgRNA over time. By considering the expression in the tested cells and the dysregulation of the miRNAs in cancer specimens, we identified five HeLa pro-fitness and cervical cancer up-regulated miRNAs (miR-31-5p, miR-92b-3p, miR-146b-5p, miR-151a-3p, and miR-194-5p). Similarly, we identified six NCI-N87 pro-fitness and gastric cancer up-regulated miRNAs (miR-95-3p, miR-181a-5p, miR-188-5p, miR-196b-5p, miR-584-5p, and miR-1304-3p), as well as three anti-fitness and down-regulated miRNAs (let-7a-3p, miR-100-5p, and miR-149-5p). Some of those miRNAs are known to be oncogenic or tumor-suppressive, but others are novel. Taken together, the LX-miR library is useful for genome-wide unbiased screening to identify miRNAs important for cellular fitness and likely to be useful for other functional screens.

Correlation between miR-222 and uterine cancer and its prognostic value

Relationship between the expression of miR-222 and uterine cancer was investigated to explore its prognostic value. A total of 66 patients with uterine cancer diagnosed by pathological examination in Dongying People's Hospital were enrolled from March 2014 to October 2016. Uterine cancer and adjacent tissues were collected, and the expression of miR-222 in the tissues was detected by stem-loop RT-PCR. The relationship between miR-222 expression and various clinicopathological features of uterine cancer was analyzed. All the patients were followed up to record the survival conditions. The results revealed that stem-loop RT-PCR method could specifically amplify miR-222. The expression of miR-222 in uterine cancer tissues was significantly upregulated compared with that in adjacent tissues (p<0.05). The expression level of miR-222 was significantly increased with the increase of degree of tumor differentiation (p<0.05). The expression of miR-222 in uterine cancer tissue was not significantly correlated with patients age, tumor size, gross tumor type, pathological type and FIGO stage (p>0.05). There was a significant negative correlation between the expression of miR-222 and the survival of patients with uterine cancer. In conclusion, the expression of miR-222 in uterine cancer tissues was significantly upregulated in uterine cancer and negatively correlated with prognosis. miR-222 may play a pivotal role in the development and progression of uterine cancer. It is expected that miR-222 will be an indicator and target for the treatment and prognosis of uterine cancer.

[MicroRNA-218 promotes osteosarcoma cell apoptosis by down-regulating oncogene B lymphoma mouse Moloney leukemia virus insertion region 1]

OBJECTIVE

To investigate the tumor-suppressing effect of microRNA-218 (miR-218) in osteosarcoma (OS) and explore its molecular mechanism.

METHODS

We examined the expression levels of miR-218 in 68 pairs of OS and adjacent tissue samples using qRT-PCR.Cultured human OS cell line Saos-2 was transfected with miR-218 mimics or anti-miR-218 mimics, and the cell apoptosis was assessed using CCK-8 assay, annexin V-FITC staining and Western blotting.We also analyzed the potential functional targets of miR-218 in Saos-2 cells using luciferase assay, qRT-PCR and Western blotting.

RESULTS

The expression level of miR-218 was lowered by at least 8 folds in OS tissues as compared with the adjacent tissues.In cultured Saos-2 cells, transfection with miR-218 mimics for 24, 36, and 48 h resulted in a significant reduction in the cell viability, while transfection with anti-miR-218 mimics significantly increased the cell viability.The cells transfected with miR-218 mimics showed an obviously enhanced expression of cleaved poly (ADP-ribose) polymerase (C-PARP) as compared with the cells transfected with anti-miR-218 mimics and the control cells.Flow cytometry demonstrated obviously increased apoptosis of the cells following miR-218 mimics transfection.We identified the oncogene B lymphoma mouse Moloney leukemia virus insertion region 1 (BMI-1) as a specific target of miR-218 in Saos-2 cells. BMI-1 expressions at both the mRNA and protein levels were significantly reduced in Saos-2 cells overexpressing miR-218 but increased in the cells with miR-218 knockdown as compared to the control cells.Luciferase reporter assay indicated that miR-218 directly inhibited the expression of BMI-1 via binding to its 3'-UTR in OS cells.

CONCLUSION

miR-218 can promote OS cell apoptosis and plays the role as a tumor suppressor by down-regulating BMI-1.

PTBP1 enhances miR-101-guided AGO2 targeting to MCL1 and promotes miR-101-induced apoptosis

Myeloid cell leukemia 1 (MCL1) is a key anti-apoptotic protein belonging to the BCL-2 protein family. To preserve normal cellular homeostasis, cells must maintain strict control over MCL1 expression. Overexpression of MCL1 has been identified as a key contributor to tumorigenesis, and further enables resistance to a number of anti-cancer chemotherapies. Thus, there is an ongoing interest to develop selective MCL1 inhibitors. In order to better target MCL1, it is essential to understand the molecular mechanisms that regulate MCL1 expression in cells. While MCL1 expression is tightly controlled by multiple mechanisms, the post-transcriptional regulation of MCL1 mRNA is poorly studied. Our previous work identified that polypyrimidine tract binding protein 1 (PTBP1) binds to MCL1 mRNA and represses MCL1 expression by destabilizing MCL1 mRNA. In this report, we show that PTBP1 modulates MCL1 expression by regulating the microRNA (miRNA) direction of the miRNA-induced silencing complex (miRISC) to MCL1. We demonstrate that PTBP1 enhances miR-101-guided AGO2 interaction with MCL1, thereby regulating miR-101-induced apoptosis and clonogenic cell survival inhibition in cells. Taken together, not only do these studies expand our understanding on the regulation of MCL1, they also demonstrate that PTBP1 and miRNAs can function cooperatively on a shared target mRNA.

Decreased miR-320a promotes invasion and metastasis of tumor budding cells in tongue squamous cell carcinoma

We aimed to determine the specific miRNA profile of tumor budding cells and investigate the potential role of miR-320a in invasion and metastasis of tongue squamous cell carcinoma (TSCC). We collected tumor budding cells and paired central tumor samples from five TSCC specimens with laser capture microdissection and examined the specimens using a miRNA microarray. The specific miRNA signature of tumor budding cells was identified. We found that miR-320a was dramatically decreased in tumor budding cells. Knockdown of miR-320a significantly enhanced migration and invasion of TSCC cell lines. Suz12 was shown to be a direct target of miR-320a. Similar results were also observed in nude mouse models. Multivariate analysis indicated that miR-320a was an independent prognostic factor. Kaplan–Meier analysis demonstrated that decreased miR-320a and high intensity of tumor budding were correlated with poor survival rate, especially in the subgroup with high-intensity tumor budding and low expression of miR-320a. We concluded that decreased expression of miR-320a could promote invasion and metastasis of tumor budding cells by targeting Suz12 in TSCC. A combination of tumor budding and miR-320a may serve as an index to identify an aggressive sub-population of TSCC cells with high metastatic potential.

MiR-320 promotes B cell proliferation and the production of aberrant glycosylated IgA1 in IgA nephropathy

IgA nephropathy (IgAN) is one of the most common primary glomerulonephritis. However, the etiology of this disease is complex and the pathogenesis of IgAN is still unknown. MicroRNAs (miRNAs) play important roles in a lot of pathological and physiological processes. In this study, we showed that the expression of miR-320 was significantly upregulated in renal tissues and urinary of IgAN patients. Moreover, the intra-renal expression level of miR-320 had significant correlation with miR-320 expression in the urinary of IgAN patients. Overexpression of miR-320 increased B cell proliferation and promoted cyclin D1 expression. Furthermore, we identified that PTEN was direct target gene of miR-320 in the B cell. Ectopic expression of miR-320 suppressed PTEN expression. Overexpression of miR-320 decreased Cosmc expression in the B cell. In addition, we demonstrated that Cosmc expression was significantly downregulated in the renal tissues and urinary of IgAN patients. The intra-renal expression level of Cosmc had significant correlation with Cosmc expression of urinary in IgAN patients. We proved that the expression level of Cosmc was negatively correlated with the expression of miR-320 in the renal tissues of IgAN patients. Overexpression of miR-320 promoted the B cell proliferation through suppressing PTEN expression. Taken together, these data suggested that miR-320 acted an important role in the development of IgAN.

Post-Transcriptional Regulation of Anti-Apoptotic BCL2 Family Members

Anti-apoptotic B cell lymphoma 2 (BCL2) family members (BCL2, MCL1, BCLxL, BCLW, and BFL1) are key players in the regulation of intrinsic apoptosis. Dysregulation of these proteins not only impairs normal development, but also contributes to tumor progression and resistance to various anti-cancer therapies. Therefore, cells maintain strict control over the expression of anti-apoptotic BCL2 family members using multiple mechanisms. Over the past two decades, the importance of post-transcriptional regulation of mRNA in controlling gene expression and its impact on normal homeostasis and disease have begun to be appreciated. In this review, we discuss the RNA binding proteins (RBPs) and microRNAs (miRNAs) that mediate post-transcriptional regulation of the anti-apoptotic BCL2 family members. We describe their roles and impact on alternative splicing, mRNA turnover, and mRNA subcellular localization. We also point out the importance of future studies in characterizing the crosstalk between RBPs and miRNAs in regulating anti-apoptotic BCL2 family member expression and ultimately apoptosis.

MicroRNA-320 Enhances Radiosensitivity of Glioma Through Down-Regulation of Sirtuin Type 1 by Directly Targeting Forkhead Box Protein M1

Glioma is the most common cancer in human brain system and seriously threatens human health. miRNA-320 has been demonstrated to be closely correlated with the development of glioma. However, its effect and molecular mechanism underlying radioresistance have not been fully elucidated in glioma. Here, RT-qPCR assay was used to assess the expressions of miR-320 and forkhead box protein M1 (FoxM1) mRNA in glioma tumor tissues and cells. The effects of miR-320, FoxM1 and sirtuin type 1 (Sirt1) on radiosensitivity in glioma cells were evaluated by clone formation assay, apoptosis assay, histone H2AX phosphorylation level (γH2AX) detection and caspase 3 activity analysis, respectively. The direct interaction between miR-320 and FoxM1 was detected by luciferase assay. The protein levels of FoxM1, Sirt1 and γH2AX were measured by western blot assay. We found that miR-320 expression was down-regulated and FoxM1 expression was up-regulated in radioresistant glioma tissues and IR-treated glioma cells. miR-320 overexpression dramatically enhanced radiosensitivity, promoted apoptosis, and improved γH2AX expression and caspase 3 activity in glioma cells. Luciferase reporter assay and western blot assay further validated that miR-320 suppressed FoxM1 expression by directly targeting 3' UTR region of FoxM1. Moreover, miR-320 inhibited Sirt1 expression via targeting FoxM1 in glioma cells. Furthermore, overexpression of FoxM1 and Sirt1 strikingly attenuated miR-320-induced increase of radiosensitivity, apoptosis and γH2AX expression in glioma cells. In conclusion, miR-320 enhanced radiosensitivity of glioma cells through down-regulation of Sirt1 by directly targeting FoxM1.

Serum levels of miR-320 family members are associated with clinical parameters and diagnosis in prostate cancer patients

We studied the association of the serum levels of the microRNA family members miR-320a/-b/-c with clinico-pathological data to assess their applicability as diagnostic biomarker in prostate cancer (PCa) patients. The levels of miR-320a/-b/-c in 3 groups were evaluated by qRT-PCR (145 patients with PCa, 31 patients with benign prostatic hyperplasia (BPH) and 19 healthy controls). The levels of the three family members of miR-320 were directly correlated within each group (P < 0.001), but they differed significantly among the three groups (P < 0.001). The serum levels of the miR-320 family members were significantly increased in older patients compared to younger patients (≤ 66 years vs. > 66 years, P ≤ 0.001). In addition, the levels of all three miR-320 family members were significantly different in patients with low tumor stage compared with those with high tumor stage (miR-320a: P = 0.034; miR-320b: P = 0.006; miR-320c: P = 0.007) and in patients with low serum PSA compared with those with high serum PSA (≤ 4 ng vs. > 4 ng; miR-320a: P = 0.003; miR-320b: P = 0.003; miR-320c: P = 0.006). The levels of these miRNAs were inversely correlated with serum PSA levels. Detection in the serum samples of PCa patients with or without PSA relapse revealed higher levels of miR-320a/-b/-c in the group without PSA relapse before/after radical prostatectomy than in that with PCa relapse. In summary, the differences among the PCa/BPH/healthy control groups with respect to miR-320a/-b/-c levels in conjunction with higher levels in patients without a PSA relapse than in those with a relapse suggest the diagnostic potential of these miRNA-320 family members in PCa patients.

MicroRNA‑320 targets mitogen‑activated protein kinase 1 to inhibit cell proliferation and invasion in epithelial ovarian cancer

Ovarian cancer is the second most frequently occurring cancer and the most fatal gynecological malignancy of all gynecological cancers worldwide. MicroRNAs (miR) have been reported to be downregulated or upregulated in a variety of human malignancies, and involved in the formation and progression of the majority of human cancers, including epithelial ovarian cancer (EOC). miR‑320 has been identified as a tumor suppressor in multiple human cancers. However, the expression levels, biological role and underlying mechanisms of miR‑320 in EOC remain to be elucidated. In the present study, reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR) was performed to detect miR‑320 expression in EOC tissues and cell lines. Following transfection with miR‑320 mimics, Cell Counting Kit 8 and cell invasion assays were utilized to investigate the effects of miR‑320 on EOC cell proliferation and invasion. Bioinformatic analysis, luciferase reporter assay, RT‑qPCR and western blotting were used to explore the underlying mechanism of how miR‑320 affects cell proliferation and invasion in EOC. Mitogen‑activated protein kinase (MAPK) 1 expression and its association with the miR‑320 expression level was examined in EOC tissues. The role of MAPK1 in EOC cells was additionally evaluated by using a loss‑of‑function assay. The results demonstrated that miR‑320 was markedly downregulated in EOC tissues and cell lines. A decreased miR‑320 expression was significantly correlated with the Federation of Gynecology and Obstetrics stage and lymph node metastasis of EOC patients. Additionally, reintroduction of miR‑320 expression suppressed cell proliferation and invasion in EOC. Furthermore, it was verified that MAPK1 is a direct target gene of miR‑320 in EOC. MAPK1 expression was markedly upregulated in EOC tissues and inversely correlated with miR‑320 expression. Furthermore, silencing of MAPK1 by RNA interference inhibited cell proliferation and invasion of EOC cells. Overall, the present study demonstrated that miR‑320 may act as a useful diagnostic and therapeutic target in the treatment of EOC.

LncRNA SNHG12 regulates gastric cancer progression by acting as a molecular sponge of miR‑320

Gastric cancer (GC) is one of the most common malignancies worldwide. Previous studies have focused on long non‑coding RNAs (lncRNAs), which have important roles in the development and progression of GC. The present study aimed to clarify the expression and function of lncRNA small nucleolar RNA host gene 12 (SNHG12) in GC. The expression and the clinical characteristics of GC were analyzed in the samples from patients with GC and matched adjacent normal tissues. The present study determined that SNHG12 was significantly overexpressed in GC and its expression level was highly associated with tumor size, tumor‑node‑metastasis stage, distant metastasis, lymphatic metastasis. Patients with high SNHG12 expression had a short survival period. Additionally, inhibition of SNHG12 in GC cell lines SGC‑7901 and AGS suppressed cell growth, colony formation, proliferation and invasion. MicroRNA (miR)‑320, a putative target gene of SNHG12, was inversely correlated with SNHG12 expression in GC tissues and cell lines. In addition, the present study determined that miR‑320 was directly regulated by SNHG12 and suppression of miR‑320 expression reversed the inhibitory effects of SNHG12 siRNA on GC cell proliferation and invasion. These findings revealed that SNHG12 acts as a tumor promoter by directly targeting miR‑320 in GC, suggesting a potential novel biomarker for the diagnosis and prognosis of GC.

microRNA‑211 suppresses the growth and metastasis of cervical cancer by directly targeting ZEB1

Of gynecological cancers, cervical cancer has the second highest incidence globally and is a major cause of cancer‑associated mortality in women. An increasing number of studies have reported that microRNAs (miRNAs) have important roles in cervical cancer carcinogenesis and progression through regulation of various critical protein‑coding genes. The aim of the present study was to investigate the expression and biological roles of miRNA‑211 (miR‑211) in cervical cancer and its underlying molecular mechanism. The results of reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR) demonstrated that the expression levels of miR‑211 in cervical cancer tissues and cell lines were significantly lower compared with adjacent normal tissues and the normal human cervix epithelial cell line, respectively. Furthermore, upregulation of miR‑211 by transfection with miR‑211 mimics inhibited cell proliferation, migration and invasion of cervical cancer, as determined by MTT, Transwell and Matrigel assays, respectively. Bioinformatics analysis and luciferase reporter assay results indicated that zinc finger E‑box binding homeobox 1 (ZEB1) may be a direct target gene of miR‑211. In addition, RT‑qPCR and western blot analysis results demonstrated that miR‑211 overexpression markedly reduced ZEB1 expression at mRNA and protein levels in cervical cancer. Furthermore, the effects of ZEB1 downregulation on the proliferation, migration and invasion of cervical cancer cells were similar to those induced by miR‑211 overexpression. These results indicate that miR‑211 may act as a tumor suppressor in cervical cancer by directly targeting ZEB1. Therefore, miR‑211/ZEB1‑based targeted therapy may represent a potential novel treatment for patients with cervical cancer.

MicroRNA-320 inhibits cell proliferation and invasion in breast cancer cells by targeting SOX4

Dysregulation of microRNAs (miRs) can contribute to cancer development and progression. In the present study, the function and underlying molecular mechanisms of miR-320 in breast cancer tumorigenesis and progression were investigated. The results of a reverse transcription-quantitative polymerase chain reaction analysis demonstrated that miR-320 was frequently downregulated in breast cancer tissues compared with adjacent normal tissues. In addition, knockdown of miR-320 in breast cancer cell lines promoted cell proliferation and invasion in vitro, whereas miR-320 overexpression had the opposite effect. Furthermore, a Dual-Luciferase reporter assay indicated that SRY-box 4 (SOX4) is a direct target of miR-320, and the restoration of SOX4 in miR-320-overexpressing cells attenuated the tumor-suppressive effects of miR-320. Collectively, these results indicated that miR-320 acts as a tumor suppressor in breast cancer tumorigenesis and progression.

MicroRNA expression profiling of porcine mammary epithelial cells after challenge with Escherichia coli in vitro

Background

Coliform mastitis is a symptom of postpartum dysgalactia syndrome (PDS), a multifactorial infectious disease of sows. Our previous study showed gene expression profile change after bacterial challenge of porcine mammary epithelial cells (PMECs). These mRNA expression changes may be regulated through microRNAs (miRNAs) which play critical roles in biological processes. Therefore, miRNA expression profile was investigated in PMECs.

Results

PMECs were isolated from three lactating sows and challenged with heat-inactivated potential mastitis-causing pathogen Escherichia coli (E. coli) for 3 h and 24 h, in vitro. At 3 h post-challenge with E. coli, target gene prediction identified a critical role of miRNAs in regulation of host immune responses and homeostasis of PMECs mediated by affecting pathways including cytokine binding (miR-202, miR-3277, miR-4903); IL-10/PPAR signaling (miR-3277, miR-4317, miR-548); and NF-ĸB/TNFR2 signaling (miR-202, miR-2262, miR-885-3p). Target genes of miRNAs in PMECs at 24 h were significantly enriched in pathways associated with interferon signaling (miR-210, miR-23a, miR-1736) and protein ubiquitination (miR-125, miR-128, miR-1280).

Conclusions

This study provides first large-scale miRNA expression profiles and their predicted target genes in PMECs after contact with a potential mastitis-causing E. coli strain. Both, highly conserved miRNAs known from other species as well as novel miRNAs were identified in PMECs, representing candidate predictive biomarkers for PDS. Time-dependent pathogen clearance suggests an important role of PMECs in inflammatory response of the first cellular barrier of the porcine mammary gland.

Electronic supplementary material

The online version of this article (doi:10.1186/s12864-017-4070-2) contains supplementary material, which is available to authorized users.

MicroRNA profile for health risk assessment: Environmental exposure to persistent organic pollutants strongly affects the human blood microRNA machinery

Persistent organic pollutants (POPs) are synthetic chemical substances that accumulate in our environment. POPs such as polychlorinated biphenyls (PCBs), hexachlorobenzene (HCB) and dichlorodiphenyltrichloroethane (DDT) have been classified as carcinogenic to humans and animals. Due to their resistance to biodegradation humans are still exposed to these compounds worldwide. We aim to evaluate the miRNA and transcriptomic response of a human population exposed to POPs. The miRNA and transcriptomic response was measured in blood of healthy subjects by microarray technology and associated with the serum concentrations of six PCB congeners, DDE (a common DDT metabolite), and HCB. A total of 93 miRNA levels appeared significantly associated with the POP-exposure (FDR < 0.05). The miRNA profile includes four tumor suppressor miRNAs, namely miR-193a-3p, miR-152, miR-31-5p and miR-34a-5p. Integration of the miRNA profile with the transcriptome profile suggests an interaction with oncogenes such as MYC, CCND1, BCL2 and VEGFA. We have shown that exposure to POPs is associated with human miRNA and transcriptomic responses. The identified miRNAs and target genes are related to various types of cancer and involved in relevant signaling pathways like wnt and p53. Therefore, these miRNAs may have great potential to contribute to biomarker-based environmental health risk assessment.

MicroRNA-320 regulates autophagy in retinoblastoma by targeting hypoxia inducible factor-1α

Retinoblastoma (RB) is the most common malignancy in children. Due to refractory mechanisms of chemoresistance and the toxicity of chemotherapies, novel therapies for RB treatment are urgently required. MicroRNA-320 (miR-320) is believed to be associated with the tumorigenesis of RB, although the mechanism remains unclear. Considering the hypoxic intratumoral region, the roles of miR-320 and hypoxia inducible factor-1α (HIF-1α) in the regulation of autophagy were investigated in 30 human RB samples and WERI-RB1 cells. The results demonstrated that HIF-1α was the downstream target of miR-320, and decreased miRNA-320 or HIF-1α lead to the inhibition of autophagy in WERI-RB1 cells. Compared with WERI-RB1 cells that were not transfected, silenced HIF-1α caused a 1.41-fold increase (P<0.01) in p62, a 2.71-fold decrease of Beclin1, and inhibited miRNA-320. Silenced HIF-1α also resulted in 7.29- and 7.43-fold increases in phosphorylated-mechanistic target of rapamycin (mTOR) and mTOR, respectively. In conclusion, the present results suggest that miRNA-320 may regulate the development of autophagy by targeting HIF-1α and autophagy-related proteins in RB under hypoxic conditions.

microRNA regulators of apoptosis in cancer

This brief review summarizes our current knowledge on the microRNAs that regulate apoptosis machinery and are potentially involved in the dysregulation or deregulation of apoptosis, a well known hallmark of cancer. microRNAs are critical regulators of the most important cellular processes, including apoptosis. Expression of microRNAs is found to be dysregulated in many malignancies, leading to apoptosis inhibition in cancer, or resistance to current therapies. To date, there are over 80 microRNAs directly involved in apoptosis regulation or dysregulation that can impact cancer detection, initiation, progression, invasion, metastasis or resistance to anti-cancer therapy. Development of microRNA-based therapeutic strategies is now taking shape in the clinic. Thus, these microRNAs represent potential targets or tools for cancer therapy in the future.