miR-20a promotes migration and invasion by regulating TNKS2 in human cervical cancer cells

Tankyrase 2 promotes lung cancer cell malignancy

BACKGROUND

Tankyrase 2 (TNKS2) is a potential candidate molecular target for the prognosis and treatment of non-small cell lung cancer (NSCLC), but its biological functions are unclear.

AIM

To investigate the biological functions of TNKS2 in NSCLC.

METHODS

Using a lentiviral vector, we generated H647 model cells with TNKS2 knockdown by RNA interference and A549 model cells with TNKS2 overexpression by transfection with a TNKS2 overexpressing plasmid. Increased and decreased expression levels of TNKS2 in the two cell lines were verified using real-time reverse transcriptase-polymerase chain reaction and Western blot analyses. Cell apoptosis, proliferation, and migration were determined using flow cytometry, carboxyfluorescein succinimidyl ester staining, and scratch assay, respectively. Immunofluorescence staining was conducted to examine TNKS2 and β-catenin expression levels in the two transfected cell lines and the non-transfected cells.

RESULTS

TNKS2 mRNA and protein expression was significantly higher in the highly malignant NCI-H647 cells, while it remained at a low level in the less malignant A549 cells. Lentivirus-mediated overexpression of TNKS2 in A549 cells resulted in a 3-fold increase in gene expression and a 1.7-fold increase in protein expression (P < 0.01). Conversely, shRNA interference targeting TNKS2 Led to an 8-fold decrease in gene expression and a 3-fold decrease in protein expression (P < 0.01) in NCI-H647 cells. Furthermore, the cell apoptosis rate was significantly reduced (50%) and cell migration rate was increased (35%) in the TNKS2 overexpression group than in the control group (P < 0.05). In contrast, shTNKS2 promoted apoptosis by more than one fold and reduced migration by 60% (P < 0.05). Immunofluorescence analysis revealed enhanced nuclear localization of β-catenin fluorescence signal associated with high TNKS2 expression levels. Western blot analysis investigating TNKS2/β-catenin-related proteins indicated consistent changes between TNKS2 and β-catenin expression in lung cancer cells, whereas Axin displayed an opposite trend (P < 0.05).

CONCLUSION

The obtained results revealed that TNKS2 may serve as an adverse prognostic factor and a potential therapeutic target in NSCLC.

RNA-binding proteins and exoribonucleases modulating miRNA in cancer: the enemy within

Recent progress in the investigation of microRNA (miRNA) biogenesis and the miRNA processing machinery has revealed previously unknown roles of posttranscriptional regulation in gene expression. The molecular mechanistic interplay between miRNAs and their regulatory factors, RNA-binding proteins (RBPs) and exoribonucleases, has been revealed to play a critical role in tumorigenesis. Moreover, recent studies have shown that the proliferation of hepatocellular carcinoma (HCC)-causing hepatitis C virus (HCV) is also characterized by close crosstalk of a multitude of host RBPs and exoribonucleases with miR-122 and its RNA genome, suggesting the importance of the mechanistic interplay among these factors during the proliferation of HCV. This review primarily aims to comprehensively describe the well-established roles and discuss the recently discovered understanding of miRNA regulators, RBPs and exoribonucleases, in relation to various cancers and the proliferation of a representative cancer-causing RNA virus, HCV. These have also opened the door to the emerging potential for treating cancers as well as HCV infection by targeting miRNAs or their respective cellular modulators.

The Influence of Telomere-Related Gene Variants, Serum Levels, and Relative Leukocyte Telomere Length in Pituitary Adenoma Occurrence and Recurrence

In this study, we examined 130 patients with pituitary adenomas (PAs) and 320 healthy subjects, using DNA samples from peripheral blood leukocytes purified through the DNA salting-out method. Real-time polymerase chain reaction (RT-PCR) was used to assess single nucleotide polymorphisms (SNPs) and relative leukocyte telomere lengths (RLTLs), while enzyme-linked immunosorbent assay (ELISA) was used to determine the levels of TERF1, TERF2, TNKS2, CTC1, and ZNF676 in blood serum. Our findings reveal several significant associations. Genetic associations with pituitary adenoma occurrence: the TERF1 rs1545827 CT + TT genotypes were linked to 2.9-fold decreased odds of PA occurrence. Conversely, the TNKS2 rs10509637 GG genotype showed 6.5-fold increased odds of PA occurrence. Gender-specific genetic associations with PA occurrence: in females, the TERF1 rs1545827 CC + TT genotypes indicated 3.1-fold decreased odds of PA occurrence, while the TNKS2 rs10509637 AA genotype was associated with 4.6-fold increased odds. In males, the presence of the TERF1 rs1545827 T allele was associated with 2.2-fold decreased odds of PA occurrence, while the TNKS2 rs10509637 AA genotype was linked to a substantial 10.6-fold increase in odds. Associations with pituitary adenoma recurrence: the TNKS2 rs10509637 AA genotype was associated with 4.2-fold increased odds of PA recurrence. On the other hand, the TERF1 rs1545827 CT + TT genotypes were linked to 3.5-fold decreased odds of PA without recurrence, while the TNKS2 rs10509637 AA genotype was associated with 6.4-fold increased odds of PA without recurrence. Serum TERF2 and TERF1 levels: patients with PA exhibited elevated serum TERF2 levels compared to the reference group. Conversely, patients with PA had decreased TERF1 serum levels compared to the reference group. Relative leukocyte telomere length (RLTL): a significant difference in RLTL between the PA group and the reference group was observed, with PA patients having longer telomeres. Genetic associations with telomere shortening: the TERF1 rs1545827 T allele was associated with 1.4-fold decreased odds of telomere shortening. In contrast, the CTC1 rs3027234 TT genotype was linked to 4.8-fold increased odds of telomere shortening. These findings suggest a complex interplay between genetic factors, telomere length, and pituitary adenoma occurrence and recurrence, with potential gender-specific effects. Furthermore, variations in TERF1 and TNKS2 genes may play crucial roles in telomere length regulation and disease susceptibility.

MiR-199a-3p Induces Mesenchymal to Epithelial Transition of Keratinocytes by Targeting RAP2B

Cutaneous squamous cell carcinoma (CSCC) is an epidermal skin cancer that evolves from normal epidermis along several pre-malignant stages. Previously we found specific miRNAs alterations in each step along these stages. miR-199a-3p expression decreases at the transition to later stages. A crucial step for epithelial carcinoma cells to acquire invasive capacity is the disruption of cell-cell contacts and the gain of mesenchymal motile phenotype, a process known as epithelial-to-mesenchymal transition (EMT). This study aims to study the role of decreased expression of miR-199a-3p in keratinocytes' EMT towards carcinogenesis. First, we measured miR-199a-3p in different stages of epidermal carcinogenesis. Then, we applied Photoactivatable Ribonucleoside-Enhanced Crosslinking and Immunoprecipitation (PAR-CLIP) assay to search for possible biochemical targets of miR-199a-3p and verified that Ras-associated protein B2 (RAP2B) is a bona-fide target of miR-199a-3p. Next, we analyzed RAP2B expression, in CSCC biopsies. Last, we evaluated possible mechanisms leading to decreased miR-199a-3p expression. miR-199a-3p induces a mesenchymal to epithelial transition (MET) in CSSC cells. Many of the under-expressed genes in CSCC overexpressing miR-199a-3p, are possible targets of miR-199a-3p and play roles in EMT. RAP2B is a biochemical target of miR-199a-3p. Overexpression of miR-199a-3p in CSCC results in decreased phosphorylated focal adhesion kinase (FAK). In addition, inhibiting FAK phosphorylation inhibits EMT marker genes' expression. In addition, we proved that DNA methylation is part of the mechanism by which miR-199a-3p expression is inhibited. However, it is not by the methylation of miR-199a putative promoter. These findings suggest that miR-199a-3p inhibits the EMT process by targeting RAP2B. Inhibitors of RAP2B or FAK may be effective therapeutic agents for CSCC.

Characterization of circRNA–miRNA–mRNA networks regulating oxygen utilization in type II alveolar epithelial cells of Tibetan pigs

Understanding the signaling pathway regulatory mechanisms in type II alveolar epithelial (ATII) cells, the progenitor cells responsible for proliferating and regenerating type I alveolar epithelial (ATI) and ATII cells, in Tibetan pigs is beneficial for exploring methods of preventing and repairing cellular damage during hypoxia. We simulated a hypoxic environment (2% O2) for culture ATII cells of Tibetan pigs and Landrace pigs, with cells cultured under normoxic conditions (21% O2) as a control group, and performed integrated analysis of circular RNA (circRNA)–microRNA (miRNA)–messenger RNA (mRNA) regulatory axes by whole-transcriptome sequencing. Functional enrichment analysis indicated that the source genes of the differential expressed circRNAs (DEcircRNAs) were primarily involved in cell proliferation, cellular processes, and cell killing. A series of DEcircRNAs were derived from inhibitors of apoptosis proteins and led to a key autonomous effect as modulators of cell repair in Tibetan pigs under hypoxia. The significant higher expression of COL5A1 in TL groups may inhibited apoptosis of ATII cells in Tibetan pigs under lower oxygen concentration, and may lead their better survive in the hypoxia environment. In addition, a competing endogenous RNA (ceRNA) network of functional interactions was constructed that included novel_circ_000898-ssc-miR-199a-5p-CAV1 and novel_circ_000898-ssc-miR-378-BMP2, based on the node genes ssc-miR-199a-5p and ssc-miR-378, which may regulate multiple miRNAs and mRNAs that mediate endoplasmic reticulum (ER) stress-induced apoptosis and inflammation and attenuate hypoxia-induced injury in ATII cells under hypoxic conditions. These results broaden our knowledge of circRNAs, miRNAs, and mRNAs associated with hypoxia and provide new insights into the hypoxic response of ATII cells in Tibetan pigs.

Disease progression role as well as the diagnostic and prognostic value of microRNA-21 in patients with cervical cancer: A systematic review and meta-analysis

Introduction

Cervical cancer is the fourth commonest and the fourth leading cause of cancer death in females globally. The upregulated expression of microRNA-21 in cervical cancer has been investigated in numerous studies, yet given the inconsistency on some of the findings, a systematic review and meta-analysis is needed. Therefore, the aim of this systematic review and meta-analysis is to investigate the role in disease progression as well as the diagnostic and prognostic value of microRNA-21 in patients with cervical cancer.

Methods

Literature search was carried out through visiting several electronic databases including PubMed/MEDLINE/ PubMed Central, Web of Science, Embase, WorldCat, DOAJ, ScienceDirect, and Google Scholar. After extraction, data analysis was carried out using Rev-Man 5.3, STATA 15.0 and Meta-disk 1.4. I2 and meta-bias statistics assessed heterogeneity and publication bias of the included studies, respectively. The area under summary receiver operating characteristic curve and other diagnostic indexes were used to estimate diagnostic accuracy.

Result

A total of 53 studies were included for this systematic review and meta-analysis. This study summarized that microRNA-21 targets the expression of numerous genes that regulate their subsequent downstream signaling pathways which promote cervical carcinogenesis. The targets addressed in this study included TNF-α, CCL20, PTEN RasA1, TIMP3, PDCD-4, TPM-1, FASL, BTG-2, GAS-5, and VHL. In addition, the meta-analysis of reports from 6 eligible studies has demonstrated that the overall area under the curve (AUC) of summary receiver operating characteristic (SROC) of microRNA-21 as a diagnostic accuracy index for cervical cancer was 0.80 (95% CI: 0.75, 0.86). In addition, evidence from studies revealed that upregulated microRNA-21 led to worsening progression and poor prognosis in cervical cancer patients.

Conclusion

microRNA-21 is an oncogenic microRNA molecule playing a key role in the development and progression of cervical malignancy. It has good diagnostic accuracy in the diagnosis of cervical cancer. In addition, the upregulation of microRNA-21 could predict a worse outcome in terms of prognosis in cervical cancer patients.

Gene Therapy for Malignant and Benign Gynaecological Disorders: A Systematic Review of an Emerging Success Story

Simple Summary

This review discusses all the major advances in gene therapy of gynaecological disorders, highlighting the novel and potentially therapeutic perspectives associated with such an approach. It specifically focuses on the gene therapy strategies against major gynaecological malignant disorders, such as ovarian, cervical, and endometrial cancer, as well as benign disorders, such as uterine leiomyomas, endometriosis, placental, and embryo implantation disorders. The above therapeutic strategies, which employ both viral and non-viral systems for mutation compensation, suicide gene therapy, oncolytic virotherapy, antiangiogenesis and immunopotentiation approaches, have yielded promising results over the last decade, setting the grounds for successful clinical trials.

Abstract

Despite the major advances in screening and therapeutic approaches, gynaecological malignancies still present as a leading cause of death among women of reproductive age. Cervical cancer, although largely preventable through vaccination and regular screening, remains the fourth most common and most lethal cancer type in women, while the available treatment schemes still pose a fertility threat. Ovarian cancer is associated with high morbidity rates, primarily due to lack of symptoms and high relapse rates following treatment, whereas endometrial cancer, although usually curable by surgery, it still represents a therapeutic problem. On the other hand, benign abnormalities, such as fibroids, endometriosis, placental, and embryo implantation disorders, although not life-threatening, significantly affect women’s life and fertility and have high socio-economic impacts. In the last decade, targeted gene therapy approaches toward both malignant and benign gynaecological abnormalities have led to promising results, setting the ground for successful clinical trials. The above therapeutic strategies employ both viral and non-viral systems for mutation compensation, suicide gene therapy, oncolytic virotherapy, antiangiogenesis and immunopotentiation. This review discusses all the major advances in gene therapy of gynaecological disorders and highlights the novel and potentially therapeutic perspectives associated with such an approach.

End-to-end computational approach to the design of RNA biosensors for detecting miRNA biomarkers of cervical cancer

Cervical cancer is a global public health subject as it affects women in the reproductive ages, and accounts for the second largest burden among cancer patients worldwide with an unforgiving 50% mortality rate. Relatively scant awareness and limited access to effective diagnosis have led to this enormous disease burden, calling for point-of-care, minimally invasive diagnosis methods. Here, an end-to-end quantitative unified pipeline for diagnosis has been developed, beginning with identification of optimal biomarkers, concurrent design of toehold switch sensors, and finally simulation of the designed diagnostic circuits to assess performance. Using miRNA expression data in the public domain, we identified miR-21–5p and miR-20a-5p as blood-based miRNA biomarkers specific to early-stage cervical cancer employing a multi-tier algorithmic screening. Synthetic riboregulators called toehold switches specific to the biomarker panel were then designed. To predict the dynamic range of toehold switches for use in genetic circuits as biosensors, we used a generic grammar of these switches, and built a neural network model of dynamic range using thermodynamic features derived from mRNA secondary structure and interaction. Second-generation toehold switches were used to overcome the design challenges associated with miRNA biomarkers. The resultant model yielded an adj. R² ∼0.71, outperforming earlier models of toehold-switch dynamic range. Reaction kinetics modelling was performed to predict the sensitivity of the second-generation toehold switches to the miRNA biomarkers. Simulations showed a linear response between 10 nM and 100 nM before saturation. Our study demonstrates an end-to-end computational workflow for the efficient design of genetic circuits geared towards the effective detection of unique genomic/nucleic-acid signatures. The approach has the potential to replace iterative experimental trial and error, and focus time, money, and efforts. All software including the toehold grammar parser, neural network model and reaction kinetics simulation are available as open-source software (https://github.com/SASTRA-iGEM2019) under GNU GPLv3 licence.

Ebola Virus Encodes Two microRNAs in Huh7-Infected Cells

MicroRNAs (miRNAs) are important gene regulatory molecules involved in a broad range of cellular activities. Although the existence and functions of miRNAs are clearly defined and well established in eukaryotes, this is not always the case for those of viral origin. Indeed, the existence of viral miRNAs is the subject of intense controversy, especially those of RNA viruses. Here, we characterized the miRNA transcriptome of cultured human liver cells infected or not with either of the two Ebola virus (EBOV) variants: Mayinga or Makona; or with Reston virus (RESTV). Bioinformatic analyses revealed the presence of two EBOV-encoded miRNAs, miR-MAY-251 and miR-MAK-403, originating from the EBOV Mayinga and Makona variants, respectively. From the miRDB database, miR-MAY-251 and miR-MAK-403 displayed on average more than 700 potential human host target candidates, 25% of which had a confidence score higher than 80%. By RT-qPCR and dual luciferase assays, we assessed the potential regulatory effect of these two EBOV miRNAs on selected host mRNA targets. Further analysis of Panther pathways unveiled that these two EBOV miRNAs, in addition to general regulatory functions, can potentially target genes involved in the hemorrhagic phenotype, regulation of viral replication and modulation of host immune defense.

Cervical cancer development, chemoresistance, and therapy: a snapshot of involvement of microRNA

Cervical cancer (CC) is one of the leading causes of death in women due to cancer and a major concern in the developing world. Persistent human papilloma virus (HPV) infection is the major causative agent for CC. Besides HPV infection, genetic and epigenetic factors including microRNA (miRNA) also contribute to the malignant transformation. Earlier studies have revealed that miRNAs participate in cell proliferation, invasion and metastasis, angiogenesis, and chemoresistance processes by binding and inversely regulating the target oncogenes or tumor suppressor genes. Based on functions and mechanistic insights, miRNAs have been identified as cellular modulators that have an enormous role in diagnosis, prognosis, and cancer therapy. Signatures of miRNA could be used as diagnostic markers which are necessary for early diagnosis and management of CC. The therapeutic potential of miRNAs has been shown in CC; however, more comprehensive clinical trials are required for the clinical translation of miRNA-based diagnostics and therapeutics. Understanding the molecular mechanism of miRNAs and their target genes has been useful to develop miRNA-based therapeutic strategies for CC and overcome chemoresistance. In this review, we summarize the role of miRNAs in the development, progression, and metastasis of CC as well as chemoresistance. Further, we discuss the diagnostic and therapeutic potential of miRNAs to overcome chemoresistance and treatment of CC.

Association of Leukocyte Telomere Length and Genes Involved in its Regulation With Oral Carcinoma

BACKGROUND/AIM

This study aimed to determine the relationship between the relative leukocyte telomere length (RLTL) and gene polymorphisms involved in its regulation with the occurrence of oral squamous cell carcinoma (OSCC).

PATIENTS AND METHODS

Patients with OSCC and healthy subjects were examined. Genotyping and RLTL measurement were carried out using rPCR.

RESULTS

The OSCC group had longer telomeres than controls (p=0.001). Minor allele T at TERF1rs1545827 may increase RLTL shortening (p=0.047). TNKS2rs10509639 A/G and A/G+G/G genotypes were associated with a 2.6-fold increased odd (p=0.012) and a 2.4-fold increased odd (p=0.019) of RLTL elongation compared to A/A genotype. The A/G genotype was associated with a 2.6-fold increased odd (p=0.011) compared to the A/A+G/G genotypes. Each G allele was associated with a 2.1-fold increased odd of longer RLTL (p=0.036).

CONCLUSION

Longer telomeres were found in patients with OSCC than in controls. The TERF1 rs1545827 and the TNKS2 rs10509639 polymorphisms were associated with an increase in RLTL.

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.

Arpin Regulates Migration Persistence by Interacting with Both Tankyrases and the Arp2/3 Complex

During cell migration, protrusion of the leading edge is driven by the polymerization of Arp2/3-dependent branched actin networks. Migration persistence is negatively regulated by the Arp2/3 inhibitory protein Arpin. To better understand Arpin regulation in the cell, we looked for its interacting partners and identified both Tankyrase 1 and 2 (TNKS) using a yeast two-hybrid screening and coimmunoprecipitation with full-length Arpin as bait. Arpin interacts with ankyrin repeats of TNKS through a C-terminal-binding site on its acidic tail, which overlaps with the Arp2/3-binding site. Arpin was found to dissolve the liquid–liquid phase separation of TNKS upon overexpression. To uncouple the interactions of Arpin with TNKS and Arp2/3, we introduced point mutations in the Arpin tail and attempted to rescue the increased migration persistence of the Arpin knockout cells using random plasmid integration or compensating knock-ins at the ARPIN locus. Arpin mutations impairing interactions with either Arp2/3 or TNKS were insufficient to fully abolish Arpin activity. Only the mutation that affected both interactions rendered Arpin completely inactive, suggesting the existence of two independent pathways, whereby Arpin controls the migration persistence.

Understanding the Molecular Mechanism of miR-877-3p Could Provide Potential Biomarkers and Therapeutic Targets in Squamous Cell Carcinoma of the Cervix

No therapeutic targets and molecular biomarkers are available in cervical cancer (CC) management. In other cancer types, micro-RNA-877-3p (miR-877-3p) has been associated with events relevant for CC development. Thus, we aimed to determine miR-877-3p role in CC. miR-877-3p levels were examined by quantitative-PCR in 117 cervical lesions and tumors. Effects on CC cell proliferation, migration, and invasion were evaluated upon anti-miR-877-3p transfection. miR-877-3p dependent molecular mechanism was comprehensively explored by proteomics, dual-luciferase reporter assay, western blot, and immunohistochemistry. Cervical tumors expressed higher miR-877-3p levels than benign lesions. miR-877-3p promoted CC cell migration and invasion, at least partly by modulating cytoskeletal protein folding through the chaperonin-containing T-complex protein 1 complex. Notably, miR-877-3p silencing synergized with paclitaxel. Interestingly, miR-877-3p downregulated the levels of an in silico-predicted target, ZNF177, whose expression and subcellular location significantly distinguished high-grade squamous intraepithelial lesions (HSILs) and squamous cell carcinomas of the cervix (SCCCs). Cytoplasmic ZNF177 was significantly associated with worse progression-free survival in SCCC. Our results suggest that: (i) miR-877-3p is a potential therapeutic target whose inhibition improves paclitaxel effects; (ii) the expression and location of its target ZNF177 could be diagnostic biomarkers between HSIL and SCCC; and (iii) cytoplasmic ZNF177 is a poor-prognosis biomarker in SCCC.

DHA Abolishes the Detrimental Effect of Docetaxel on Downregulation of the MICA via Decreasing the Expression Level of MicroRNA-20a in Gastric Cancer

BACKGROUND

MHC class I chain-related protein A (MICA) is a membrane glycoprotein expressed abnormally on some malignant cells including gastric cancer (GC) cell and elicits anti-tumor immune responses. Downregulation of MICA expression could lead to immune-evasion of cancer cells.

OBJECTIVE(S)

In this study, we aimed to investigate the effect of docosahexaenoic acid (DHA) and docetaxel alone or in combination on the expression level of MICA and its regulating microRNA (miRNA), miR-20a in MKN45 GC cell line.

METHOD(S)

MKN45 GC cell line was cultured and MTT assay was performed to determine IC50 of docetaxel. Cells were treated by 18.5 μM docetaxel and 100 μM DHA. After that, RNA extraction and cDNA synthesis were done and the expression level of MICA and miR-20a were determined by quantitative real-time PCR for both treated and untreated cell lines.

RESULTS

Our findings showed less downregulation of the expression level of MICA by the combination of docetaxel/DHA (5.34-fold) compared with docetaxel (45.45-fold) and DHA (55.55-fold). Consistently, combination therapy led to the more downregulation of the expression level of the miR-20a (5.20-fold) in comparison to docetaxel (2.38-fold) and DHA (1.60-fold).

CONCLUSION(S)

As an unwanted effect of docetaxel therapy in GC, downregulation of MICA expression could lead to weak anti-tumor immune responses. By increasing the expression level of MICA, combination therapy of docetaxel with DHA would be useful to overcome this side effect.

Secondary Structural Model of MALAT1 Becomes Unstructured in Chronic Myeloid Leukemia and Undergoes Structural Rearrangement in Cervical Cancer

Long noncoding RNAs (lncRNAs) influence cellular function through binding events that often depend on the lncRNA secondary structure. One such lncRNA, metastasis-associated lung adenocarcinoma transcript 1 (MALAT1), is upregulated in many cancer types and has a myriad of protein- and miRNA-binding sites. Recently, a secondary structural model of MALAT1 in noncancerous cells was proposed to form 194 hairpins and 13 pseudoknots. That study postulated that, in cancer cells, the MALAT1 structure likely varies, thereby influencing cancer progression. This work analyzes how that structural model is expected to change in K562 cells, which originated from a patient with chronic myeloid leukemia (CML), and in HeLa cells, which originated from a patient with cervical cancer. Dimethyl sulfate-sequencing (DMS-Seq) data from K562 cells and psoralen analysis of RNA interactions and structure (PARIS) data from HeLa cells were compared to the working structural model of MALAT1 in noncancerous cells to identify sites that likely undergo structural alterations. MALAT1 in K562 cells is predicted to become more unstructured, with almost 60% of examined hairpins in noncancerous cells losing at least half of their base pairings. Conversely, MALAT1 in HeLa cells is predicted to largely maintain its structure, undergoing 18 novel structural rearrangements. Moreover, 50 validated miRNA-binding sites are affected by putative secondary structural changes in both cancer types, such as miR-217 in K562 cells and miR-20a in HeLa cells. Structural changes unique to K562 cells and HeLa cells provide new mechanistic leads into how the structure of MALAT1 may mediate cancer in a cell-type specific manner.

Flavonoid display ability to target microRNAs in cancer pathogenesis

MicroRNAs (miRNAs) are non-coding, conserved, single-stranded nucleotide sequences involved in physiological and developmental processes. Recent evidence suggests an association between miRNAs' deregulation with initiation, promotion, progression, and drug resistance in cancer cells. Besides, miRNAs are known to regulate the epithelial-mesenchymal transition, angiogenesis, autophagy, and senescence in different cancer types. Previous reports proposed that apart from the antioxidant potential, flavonoids play an essential role in miRNAs modulation associated with changes in cancer-related proteins, tumor suppressor genes, and oncogenes. Thus, flavonoids can suppress proliferation, help in the development of drug sensitivity, suppress metastasis and angiogenesis by modulating miRNAs expression. In the present review, we summarize the role of miRNAs in cancer, drug resistance, and the chemopreventive potential of flavonoids mediated by miRNAs. The potential of flavonoids to modulate miRNAs expression in different cancer types demonstrate their selectivity and importance as regulators of carcinogenesis. Flavonoids as chemopreventive agents targeting miRNAs are extensively studied in vitro, in vivo, and pre-clinical studies, but their efficiency in targeting miRNAs in clinical studies is less investigated. The evidence presented in this review highlights the potential of flavonoids in cancer prevention/treatment by regulating miRNAs, although further investigations are required to validate and establish their clinical usefulness.

RP11-81H3.2 Acts as an Oncogene via microRNA-490-3p Inhibition and Consequential Tankyrase 2 Up-Regulation in Hepatocellular Carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) is a serious threat to human lives and is usually diagnosed at the late stages. Recently, there has been a rapid advancement in the treatment options for HCC, but novel therapeutic targets are still needed, especially for precision medicine.

AIMS

We aimed to investigate the involvement of non-coding RNA RP11-81H3.2 in HCC.

METHODS

The expression of RP11-81H3.2 was examined in the blood samples of HCC patients, and in the human HCC cell lines, including HepG2, Smmc-7721, and Huh7. Cell proliferation was determined using the CCK-8 and EdU assay, and cell invasion and migration were determined using the transwell/wound healing assay. The effects of RP11-81H3.2 knockdown on in vivo tumor growth were evaluated utilizing the nude mice HepG2 tumor xenograft model.

RESULTS

Here, we have identified a long non-coding RNA, RP11-81H3.2, which is enriched in HCC and can promote its proliferation, migration, and invasion both in vitro and in vivo. In addition, our results showed that RP11-81H3.2 binds to and regulate miR-490-3p expression in the HCC cells. Moreover, we found that RP11-81H3.2 regulates the expression of TNKS2 via miR-490-3p. Further, we found that RP11-81H3.2 and miR-490-3p form a regulatory loop; the release of RP11-81H3.2 leads to the suppression of miR-490-3p expression, thus, further enhancing the expression of RP11-81H3.2.

CONCLUSIONS

Our data have provided a novel target for the diagnosis and treatment of HCC, and sheds light on the lncRNA-miRNA regulatory nexus that can control the HCC related pathogenesis.

Catalytic hairpin assembly indirectly covalent on Fe3O4@C nanoparticles with signal amplification for intracellular detection of miRNA

Fluorescence resonance energy transfer, a promising method for in situ imaging of miRNA in living cells, has intrinsic limitation on sensitivity and selectivity. Herein, a fluorescent amplification strategy based on catalyzed hairpin assembly indirectly covalent on Fe₃O₄@C nanoparticles via short single-stranded DNA was investigated for cellular miRNA detection in living cells, integrating non-enzyme target-active releasing for amplifying the signal output, highly quenching efficiency of Fe₃O₄@C nanoparticles with low background, ssDNA assisted fluorescent group-fueled chain releasing from Fe₃O₄@C nanoparticles with enhanced fluorescence response. The designed platform exhibits highly sensitive in a wide linear concentration range of 0.450 pM-190 pM and is highly specific for miRNA-20a detection with the ability of discriminating one mistake base. Additionally, the CHA-Fe₃O₄@C was successfully applied in imaging visualization of miRNA-20a in the living cell. The strategy provides a promising bioassay approach for clinical research.

Insights of tankyrases: A novel target for drug discovery

Tankyrases are the group of enzymes belonging to a class of Poly (ADP-ribose) polymerase (PARP) recently named ADP-ribosyltransferase (ARTD). The two isoforms of tankyrase i.e. tankyrase1 (TNKS1) and tankyrase2 (TNKS2) were abundantly expressed in various biological functions in telomere regulation, Wnt/β-catenin signaling pathway, viral replication, endogenous hormone regulation, glucose transport, cherubism disease, erectile dysfunction, and apoptosis. The structural analysis, mechanistic information, in vitro and in vivo studies led identification and development of several classes of tankyrase inhibitors under clinical phases. In the nutshell, this review will drive future research on tankyrase as it enlighten the structural and functional features of TNKS 1 and TNKS 2, different classes of inhibitors with their structure-activity relationship studies, molecular modeling studies, as well as past, current and future perspective of the different class of tankyrase inhibitors.

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.

MicroRNA-362-3p Inhibits Migration and Invasion via Targeting BCAP31 in Cervical Cancer

Cervical cancer (CC) is the most common malignant tumor in gynecology, and metastasis is an important cause of patient death. MiRNAs (microRNAs) have been found to play key roles in cervical cancer metastasis, but the effect of miR-362-3p in CC is unclear. This study aimed to investigate the role of miR-362-3p in cervical cancer migration and invasion. We compared the expression levels of miR-362-3p in cervical cancer tissues and adjacent normal cervical tissues. In CC tissues, miR-362-3p expression was significantly down-regulated, which is related to the cancer stage and patient survival. MiR-362-3p can effectively inhibit the migration and invasion of cervical cancer cells. The dual-luciferase reporter assay results showed that BCAP31 (B cell receptor associated protein 31) is a direct target protein of miR-362-3p. The results of the immunohistochemical examination of clinical tissue samples showed that BCAP31 was abnormally highly expressed in cervical cancer, which was positively correlated with the clinical stage. BCAP31 knockdown exerted similar effects as miR-362-3p overexpression. Further GSEA analysis showed that BCAP31 may participate in multiple biological processes, such as protein transport, metabolism, and organelle organization. Our results suggest that miR-362-3p inhibits migration and invasion via directly targeting BCAP31 in cervical cancer, and restoring miR-362-3p levels may be a new treatment strategy for cervical cancer in the future.

Targeted Gene Delivery Therapies for Cervical Cancer

Despite being largely preventable through early vaccination and screening strategies, cervical cancer is the most common type of gynecological malignancy worldwide and constitutes one of the leading causes of cancer deaths in women. Patients with advanced or recurrent disease have a very poor prognosis; hence, novel therapeutic modalities to improve clinical outcomes in cervical malignancy are needed. In this regard, targeted gene delivery therapy is presented as a promising approach, which leads to the development of multiple strategies focused on different aspects. These range from altered gene restoration, immune system potentiation, and oncolytic virotherapy to the use of nanotechnology and the design of improved and enhanced gene delivery systems, among others. In the present manuscript, we review the current progress made in targeted gene delivery therapy for cervical cancer, the advantages and drawbacks and their clinical application. At present, multiple targeted gene delivery systems have been reported with encouraging preclinical results. However, the translation to humans has not yet shown a significant clinical benefit due principally to the lack of efficient vectors. Real efforts are being made to develop new gene delivery systems, to improve tumor targeting and to minimize toxicity in normal tissues.

miR-20a/Foxj2 Axis Mediates Growth and Metastasis of Colorectal Cancer Cells as Identified by Integrated Analysis

BACKGROUND MicroRNAs (miRNAs) have a significant regulatory effect on the proliferation, migration, and invasion of cells, and have been widely reported to have oncogenic or tumor-suppressive impacts on various tumors. In the present study we assessed the regulation and function of miR-20a on colorectal cancer (CRC) cell lines. MATERIAL AND METHODS qPCR was used to quantify miR-20a expression. Luciferase reporter assay was conducted to confirm Foxj2 3'UTR associations. In addition, the function of miR-20a and Foxj2 in CRC was detected using MTT, colony formation, transwell assays, and cell cycle analysis. RESULTS Our data revealed that miR-20a expression was elevated in the CRC cell lines, and cell migration, proliferation, and invasion abilities were promoted by the overexpression of miR-20a. Moreover, Foxj2 was authenticated as a direct target gene of miR-20a in CRC cells. Furthermore, we found that the ectopic Foxj2 dramatically suppressed miR-20a-promoted proliferation, migration, invasion, and xenografts in vitro and in vivo, and induced cell cycle arrest at G1 stage. CONCLUSIONS Our results showing the roles of miR-20a/Foxj2 in carcinogenesis of CRC may help improve treatment of CRC.

The Role of microRNAs, Long Non-coding RNAs, and Circular RNAs in Cervical Cancer

Prolonged infection of uterine cervix epithelium with human papillomavirus (HPV) and constitutive expression of viral oncogenes have been recognized as the main cause of the complex molecular changes leading to transformation of cervical epithelial cells. Deregulated expression of microRNAs (miRNA), long non-coding RNAs (lncRNA), and circular RNAs (circRNA) is involved in the initiation and promotion processes of cervical cancer development. Expression profiling of small RNAs in cervical neoplasia revealed up-regulated “oncogenic” miRNAs, such as miR-10a, miR-21, miR-19, and miR-146a, and down regulated “tumor suppressive” miRNAs, including miR-29a, miR-372, miR-214, and miR-218, associated with cell growth, malignant transformation, cell migration, and invasion. Also several lncRNAs, comprising among others HOTAIR, MALAT1, GAS5, and MEG3, have shown to be associated with various pathogenic processes such as tumor progression, invasion as well as therapeutic resistance and emerged as new diagnostic and prognostic biomarkers in cervical cancer. Moreover, human genes encoded circular RNAs, such as has_circ-0018289, have shown to sponge specific miRNAs and to concur to the deregulation of target genes. Viral encoded circE7 has also demonstrated to overexpress E7 oncoprotein thus contributing to cell transformation. In this review, we summarize current literature on the complex interplay between miRNAs, lncRNAs, and circRNAs and their role in cervical neoplasia.

Human Papillomavirus, MicroRNA and their Role in Cervical Cancer Progression, Diagnosis and Treatment Response: A Comprehensive Review

Human Papillomavirus (HPV) is sexually transmitted and linked with vaginal, vulvar and cervix cancers in females, penile cancer in male, while anal and oropharyngeal cancer in both genders. Cervical cancer is ranked as third most identified cancer among females globally and is the fourth leading reason of cancer related mortality. The main aim of current study is to highlight the key role of miRNA in cervical cancer development, progression and their therapeutic responses. Current study entailed more than 50 PubMed cited articles related to miRNA role in cervical cancer. Studies have elucidated the role of miRNAs regulation in gene expression at post-transcriptional and translational level by targeting significant genes and therefore involved in cervical cancer. miRNAs control several cellular pathways involved in development of pre-malignant to metastatic stage and proliferation to malignancy. Current review elucidated and elaborated the key role of miRNA their application, treatment and therapeutic responses in cervical cancer.

Human Papillomavirus Infections, Cervical Cancer and MicroRNAs: An Overview and Implications for Public Health

Human Papillomavirus (HPV) is among the most common sexually transmitted infections in both females and males across the world that generally do not cause symptoms and are characterized by high rates of clearance. Persistent infections due at least to twelve well-recognized High-Risk (HR) or oncogenic genotypes, although less frequent, can occur, leading to diseases and malignancies, principally cervical cancer. Three vaccination strategies are currently available for preventing certain HR HPVs-associated diseases, infections due to HPV6 and HPV11 low-risk types, as well as for providing cross-protection against non-vaccine genotypes. Nevertheless, the limited vaccine coverage hampers reducing the burden of HPV-related diseases globally. For HR HPV types, especially HPV16 and HPV18, the E6 and E7 oncoproteins are needed for cancer development. As for other tumors, even in cervical cancer, non-coding microRNAs (miRNAs) are involved in posttranscriptional regulation, resulting in aberrant expression profiles. In this study, we provide a summary of the epidemiological background for HPV occurrence and available immunization programs. In addition, we present an overview of the most relevant evidence of miRNAs deregulation in cervical cancer, underlining that targeting these biomolecules could lead to wide translational perspectives, allowing better diagnosis, prognosis and therapeutics, and with valuable applications in the field of prevention. The literature on this topic is rapidly growing, but advanced investigations are required to achieve more consistent findings on the up-regulated and down-regulated miRNAs in cervical carcinogenesis. Because the expression of miRNAs is heterogeneously reported, it may be valuable to assess factors and risks related to individual susceptibility.

A Functional Polymorphism in the Promoter of miR-17-92 is Associated with a Reduced Risk of Cervical Squamous Cell Carcinoma

miR-17-92 cluster was differentially expressed in cervical cancer, playing an important role in regulating cell proliferation, apoptosis, migration, and invasion. The purpose of this study was to investigate the association between polymorphisms (i.e., rs9588884, rs982873, and rs1813389) in the promoter of miR-17-92 and the risk of cervical squamous cell carcinoma (CSCC). The rs9588884 polymorphism was genotyped using a Taqman assay and the rs982873 and rs1813389 polymorphisms were genotyped using a polymerase chain reaction-restriction fragment length polymorphism method. The expression levels of miR-17-92 were determined using a quantitative PCR analysis. The rs9588884 GG genotype was associated with a reduced risk of CSCC in homozygote comparison (adjusted OR = 0.47, 95% CI, 0.30-0.75, P = 0.001), dominant model (adjusted OR = 0.67, 95% CI, 0.50-0.91, P = 0.01), and recessive model (adjusted OR = 0.57, 95% CI, 0.38-0.85, P = 0.01). The rs9588884 G allele was also associated with a reduced risk of CSCC in allele comparison (adjusted OR = 0.71, 95% CI, 0.58-0.88, P = 0.002). Moreover, patients with the rs9588884 GG genotype had lower levels of miR-20a compared with the rs9588884 CC genotype (P = 0.03). These findings indicate that the rs9588884 GG genotype was associated with lower levels of miR-20a and eventually related to the risk of CSCC in Chinese women.

microRNAs: New prognostic, diagnostic, and therapeutic biomarkers in cervical cancer

Cervical cancer is as a kind of cancer beginning from the cervix. Given that cervical cancer could be observed in women who infected with papillomavirus, regular oral contraceptives, and multiple pregnancies. Early detection of cervical cancer is one of the most important aspects of the therapy of this malignancy. Despite several efforts, finding and developing new biomarkers for cervical cancer diagnosis are required. Among various prognostic, diagnostic, and therapeutic biomarkers, miRNA have been emerged as powerful biomarkers for detection, treatment, and monitoring of response to therapy in cervical cancer. Here, we summarized various miRNAs as an employable platform for prognostic, diagnostic, and therapeutic biomarkers in the treatment of cervical cancer.

The role of miRNAs in the invasion and metastasis of cervical cancer

Cervical cancer (CC) with early metastasis of the primary tumor results in poor prognosis and poor therapeutic outcomes. MicroRNAs (miRNAs) are small, noncoding RNA molecules that play a substantial role in regulating gene expression post-transcriptionally and influence the development and progression of tumors. Numerous studies have discovered that miRNAs play significant roles in the invasion and metastasis of CC by affecting specific pathways, including Notch, Wnt/β-catenin, and phosphoinositide-3 kinase (PI3K)-Akt pathways. miRNAs also effectively modulate the process of epithelial–mesenchymal transition. Many studies provide new insights into the role of miRNAs and the pathogenesis of metastatic CC. In this review, we will offer an overview and update of our present understanding of the potential roles of miRNAs in metastatic CC.

Expression of microRNAs 16, 20a, 150 and 155 in anal squamous intraepithelial lesions from high-risk groups

Anal squamous intraepithelial lesions (ASIL) or anal intraepithelial neoplasia (AIN) are precancerous lesions. microRNAs (miRNAs) have been implicated in cervical carcinogenesis, but have never been assessed in anal precancerous lesions. Our aim was to evaluate the expression of miR-16, miR-20a, miR-150 and miR-155 in several grades of ASIL obtained from high-risk patients, submitted to anal cancer screening from July 2016 to January 2017. Lesions were classified according to the Lower Anogenital Squamous Terminology (LAST) in low-grade (LSIL) and high-grade squamous intraepithelial lesions (HSIL), and the AIN classification in AIN1, AIN2 and AIN3. A hundred and five biopsies were obtained from 60 patients. Ten samples were negative (9.5%), 63 were LSIL (60%) and 32 were HSIL (30.5%) according to the LAST. Twenty seven (26%) were negative for dysplasia, 46 were classified as AIN1 (44%), 14 as AIN2 (13%) and 18 as AIN3 (17%) according to the AIN classification. There was no statistically significant difference in the fold expression of miR-16, miR-20a, miR-150 and miR-155, according to either classification. Although non- significant, there was an increasing trend in the miR-155 fold expression from negative samples to HSIL, with the highest fold expression increase in both LSIL and HSIL compared to the other miRNAs.

MicroRNA-20a regulates cell proliferation, apoptosis and autophagy by targeting thrombospondin 2 in cervical cancer

Cervical cancer (CC) is the fourth most frequent malignancy worldwide. MicroRNAs (miRNAs) can function as potential biomarkers or therapeutic targets in multiple cancers including CC. Our present study aimed to investigate the roles and downstream targets of microRNA-20a (miR-20a) in regulating CC proliferation, apoptosis and autophagy. Here, RT-qPCR assay revealed that miR-20a was highly expressed in CC tissues and cells. Functional analysis showed that the inhibition of miR-20a resulted in reduced proliferation, increased apoptosis and downregulated autophagic activity in CC cells. Bioinformatics analysis, luciferase reporter assay and RNA immunoprecipitation (RIP) assay manifested that thrombospondin 2 (THBS2) was a target of miR-20a. Also, THBS2 expression was notably reduced in CC tissues and cells, and inversely associated with miR-20a expression in CC tissues. Restoration experiments disclosed that THBS2 knockdown abrogated miR-20a inhibitor-mediated anti-proliferation, pro-apoptosis, and anti-autophagy effects in CC cells. In summary, these data showed that the depletion of miR-20a suppressed proliferation and autophagy and induced apoptosis by targeting THBS2 in CC cells, further elucidating the roles and molecular basis of miR-20a in the development of CC.

MiR-20a, a novel promising biomarker to predict prognosis in human cancer: a meta-analysis

Background

Recently, microRNA-20a (miR-20a) has been reported to influence the clinical features and may have prognostic value in human cancers. The present meta-analysis assessed the prognostic role of miR-20a in various carcinomas.

Methods

Literature searches of seven electronic databases were performed for eligible articles of the prognostic role of miR-20a in human cancers. Hazard ratios (HR) for overall survival (OS), disease free survival (DFS), progression-free survival (PFS) as well as their 95% confidence intervals (95%CIs) were used to assess the influence of miR-20a expression on patient prognosis. Odds ratio (OR) and 95%CIs were applied to evaluate the correlation between miR-20a expression and clinicopathological characteristics.

Results

Based on the OS analyzed by log rank tests, there was a significant association between miR-20a levels and OS by fixed effects model. By subgroup analyses, the significance was also observed in the studies of specimen derived from blood and gastrointestinal cancer group. The independent prognostic role of miR-20a expression for the OS was observed significantly by fixed effects model. In addition, we observed significant association between miR-20a expression levels and DFS of log rank tests, DFS of cox regression. Significant relation of gender/differentiation and the expression level of miR-20a was identified.

Conclusions

Base on the findings, the elevated miR-20a expression level is related to poor prognosis of gastrointestinal cancer patients. As for other types of carcinomas, the results are still not stable and more studies are required to further identify miR-20a prognostic values. In addition, miR-20a expression level is relatively higher in women than that in men, and increased miR-20a expression level is linked to poor tumor differentiation.

Interleukin-18 expression in oral squamous cell carcinoma: its role in tumor cell migration and invasion, and growth of tumor cell xenografts

Oral squamous cell carcinoma (OSCC) is one of the most common head and neck malignancies. Advanced stages of the disease are associated with poor survival, highlighting a need for new treatment modalities. We previously showed that the proinflammatory cytokine interleukin‐18 (IL‐18) has a tumor suppressive role in OSCC. Here, we investigated the effects of IL‐18 on proliferation, migration, and invasion of OSCC cells ex vivo and in vitro, and in nude mouse xenografts. We report that expression of tankyrase 2 (TNKS2), β‐catenin, and N‐cadherin was higher in tumor cells than in normal mucosae, whereas the expression of IL‐18 and E‐cadherin was higher in normal than in tumor tissues. Elevated expression of IL‐18 (P < 0.01) and E‐cadherin (P = 0.034) was associated with tumor differentiation, whereas expression of TNKS2 (P < 0.01), β‐catenin (P = 0.012), and N‐cadherin (P < 0.01) was associated with tumor de‐differentiation. Furthermore, compared with the vector control, IL‐18 overexpression promoted tumor cell migration and invasion (P < 0.01), but inhibited growth of tumor cell xenografts (P < 0.05). At the protein level, expression levels of IL‐18 (P < 0.01), TNKS2 (P = 0.045), β‐catenin (P = 0.028), and N‐cadherin (P = 0.068) were upregulated in tumor cells after IL‐18 overexpression compared with those of the vector control mice, whereas expression levels of E‐cadherin (P = 0.045) were decreased. In conclusion, our data suggest that IL‐18 overexpression induces oral SCC cell invasion and metastasis by promoting the tumor cell epithelial–mesenchymal transition via the Wnt/β‐catenin signaling pathway.

miR-20a inhibits the killing effect of natural killer cells to cervical cancer cells by downregulating RUNX1

BACKGROUND

NK cells are presented in tumor microenvironments and acts as an essential defense line against multiple malignancies. Recently, miRNAs are reported to involve in the development of natural killer (NK) cells via negatively regulating gene expression. Here, we aim to explore the function and mechanism underlying how miR-20a modulated the killing effect of NK cells to cervical cancer cells.

METHODS

Abundances of miR-20a and runt-related transcription factor 1 (RUNX1) in NK cells from cervical cancer patients and healthy donors were detected by qRT-PCR and western blot. The releases of IFN-γ and TNF-α were determined by ELISA. The cytotoxicity of NK cells against cervical cancer cells was measured by CytoTox 96 non-radioactive cytotoxicity assay. Luciferase reporter, western blot, and RNA immunoprecipitation (RIP) assays were performed to assess the interaction between miR-20a and RUNX1.

RESULT

miR-20a was upregulated while RUNX1 was downregulated in NK cells from cervical cancer patients compared to healthy donors. IL-2 stimulated the releases of IFN-γ and TNF-α, and the killing effect of NK cells to cervical cancer cells, which was overturned by miR-20a introduction. RUNX1 was identified to be a target of miR-20a. Restoration of RUNX1 abolished the inhibitory effects of miR-20a on the secretions of IFN-γ and TNF-α, as well as the killing effect of NK cells to colorectal cancer cells.

CONCLUSION

miR-20a attenuated the killing effect of NK cells to cervical cancer cells by directly targeting RUNX1.

Up-regulation of miR-20a by HPV16 E6 exerts growth-promoting effects by targeting PDCD6 in cervical carcinoma cells

OBJECTIVE

MicroRNAs (miRNAs/miRs) have been reported to participate in progression of multiple tumors including cervical cancer. High-risk human papillomavirus (HPV) type 16 (HPV16) is the most common and lethal HPV type, leading to exceeding 50% of cervical cancer cases. However, the relationship between miRNA and HPV-induced cervical carcinogenesis remains elusive.

RESULTS

Here, HPV16 E6 positively regulated miR-20a expression. Overexpression of miR-20a showed growth-promoting effects on C33A cells (HPV16-negative), and knockdown of miR-20a showed growth-inhibitory effects on CaSki cells (HPV16-positive). In addition, PDCD6 was identified as a target gene of miR-20a. Overexpression of PDCD6 exerted growth-inhibitory effects (opposite to miR-20a overexpression), which could be reversed by miR-20a overexpression. More importantly, activation of AKT and p38 was observed in C33A cells overexpressing miR-20a, and the growth-promoting action of miR-20a could be abated by p38 inhibition.

CONCLUSION

Up-regulation of miR-20a by HPV16 E6 exerted growth-promoting effects by targeting PDCD6 in cervical carcinoma cells. This study demonstrated miR-20a might be a potential therapeutic target in HPV16 E6 infection type of cervical cancer.

hsa-miR-212 modulates the radiosensitivity of glioma cells by targeting BRCA1

Radioresistance remains a major challenge in the treatment of glioma, and the response of patients to radio-therapy varies considerably. MicroRNAs (miRNAs) are involved in various biological processes. The purpose of the present study was to investigate miRNAs involved in the response to radiation in glioma cell lines. Total RNA was isolated from human glioma U251 cells 30 min after γ-ray exposure and hybridized to an miRNA chip array. miRNA expression profiles were analyzed by quantitative real-time PCR. pcDNA3/EGFP-miR-212 mimic transfection was used to verify the function of miR-212 in colony formation tests, and the effect of miR-212 overexpression on U251 cells was examined by western blot analysis of apoptosis-related proteins (Bcl-2, Bax, caspase-3 and cytochrome c). The target genes of miR-212 were predicted using bioinformatic tools including miRNA databases, and breast cancer susceptibility gene 1 (BRCA1) was selected for further confirmation by EGFP fluorescence reporter and loss- and gain-of-function assays. Of the 16 candidate miRNAs showing altered expression, five were assessed by real-time PCR; miR-212 was identified as contributing to the radioresistance of glioma cells and was shown to attenuate radiation-induced apoptosis. miR-212 negatively regulated BRCA1 expression by interacting with its 3'-untranslated region, suggesting a correlation between BRCA1 expression and radiosensitivity in glioma cells. U-118MG and SHG-44 cell lines were used to confirm these observations. The response of glioma cells to radiation involves the miR-212-mediated modulation of BRCA1 gene expression, suggesting that the miR-212/BRCA1 axis may play a potential role in the radiotherapy of gliomas.

MicroRNA-140-5p targets insulin like growth factor 2 mRNA binding protein 1 (IGF2BP1) to suppress cervical cancer growth and metastasis

MicroRNAs (miRNAs) are a class of small non-coding RNA molecules that play important roles in carcinogenesis and tumor progression. Previous studies have revealed that MicroRNA-140-5p (miR-140-5p) was abnormally expressed in several cancers. However, its function and possible mechanism in cervical cancer (CC) remains unknown. In this study, the data mining results showed that miR-140-5p was down-regulated in CC specimens and the down-regulation of miR-140-5p was associated with CC poor prognosis. These observations prompted us to further investigate the roles and mechanisms of miR-140-5p in human CC pathogenesis. We found that the over-expression/inhibition of miR-140-5p significantly decreased/increased cell proliferation, migration, and invasion in CC cells in vitro. Meanwhile, the results from in vivo assays showed that the over-expression of miR-140-5p induced significantly suppression of tumor growth and metastasis in nude mice. Furthermore, Insulin like growth factor 2 mRNA binding protein 1 (IGF2BP1) was identified as a direct target of miR-140-5p, and both gain-of-function and loss-of-function assays revealed that IGF2BP1 is also a functional target of miR-140-5p. Taken together, our findings suggested a novel miR-140-5p-IGF2BP1 regulatory circuit for CC pathogenesis, and miR-140-5p may be a potential target for CC therapy.

Exosomes as secondary inductive signals involved in kidney organogenesis

The subfraction of extracellular vesicles, called exosomes, transfers biological molecular information not only between cells but also between tissues and organs as nanolevel signals. Owing to their unique properties such that they contain several RNA species and proteins implicated in kidney development, exosomes are putative candidates to serve as developmental programming units in embryonic induction and tissue interactions. We used the mammalian metanephric kidney and its nephron-forming mesenchyme containing the nephron progenitor/stem cells as a model to investigate if secreted exosomes could serve as a novel type of inductive signal in a process defined as embryonic induction that controls organogenesis. As judged by several characteristic criteria, exosomes were enriched and purified from a cell line derived from embryonic kidney ureteric bud (UB) and from primary embryonic kidney UB cells, respectively. The cargo of the UB-derived exosomes was analysed by qPCR and proteomics. Several miRNA species that play a role in Wnt pathways and enrichment of proteins involved in pathways regulating the organization of the extracellular matrix as well as tissue homeostasis were identified. When labelled with fluorescent dyes, the uptake of the exosomes by metanephric mesenchyme (MM) cells and the transfer of their cargo to the cells can be observed. Closer inspection revealed that besides entering the cytoplasm, the exosomes were competent to also reach the nucleus. Furthermore, fluorescently labelled exosomal RNA enters into the cytoplasm of the MM cells. Exposure of the embryonic kidney-derived exosomes to the whole MM in an ex vivo organ culture setting did not lead to an induction of nephrogenesis but had an impact on the overall organization of the tissue. We conclude that the exosomes provide a novel signalling system with an apparent role in secondary embryonic induction regulating organogenesis.

MicroRNA-140-5p inhibits invasion and angiogenesis through targeting VEGF-A in breast cancer

MicroRNAs (miRNAs) have been proven to be involved in cell metastasis and angiogenesis by interaction with the target mRNAs. Evidence has been confirmed that miR-140-5p is a tumor suppressor in human cancers such as breast cancer. However, the potential molecular mechanism of miR-140-5p in breast cancer invasion and angiogenesis is still poorly understood. According to our study, we reported that miR-140-5p inhibited the tumor invasion and angiogenesis of breast cancer cells both in vitro and in vivo by targeting VEGF-A. The mRNA amount of miR-140-5p was decreased in the breast cancer clinical samples and breast cancer with metastasis compared with the corresponding adjacent normal tissues and cancer without metastasis. MiR-140-5p mimics and a negative control were transfected into human MCF-7 and MDA-MB-231 cells. Transwell chambers were used to detect the invasive ability of the cells, and the angiogenic ability was assessed by tube-formation assay. The markers of invasion and angiogenesis, VEGF-A, CD31 and MMP-9, were detected by using immunohistochemistry and western blot analysis in vivo. VEGF-A was verified as a possible target gene of miR-140-5p, and corroborated by dual-luciferase reporter and ELISA. Taken together, the study elucidates the molecular mechanisms by which miR-140-5p inhibits breast cancer metastasis and angiogenesis, and provides a potent evidence for the development of a novel microRNA-targeting anticancer strategy for breast cancer patients.

Evaluation of Plasma MicroRNAs as Diagnostic and Prognostic Biomarkers in Pancreatic Adenocarcinoma: miR-196a and miR-210 Could Be Negative and Positive Prognostic Markers, Respectively

Background. Identifying diagnostic and prognostic biomarkers that could be targeted in the therapy of pancreatic cancer is essential. Objective. Investigations were conducted with respect to plasma miRNA (miR-21, miR-210, miR-155, miR-196a, miR-20a, and miR-25) expression and clinicopathologic factors to evaluate the prognostic value of miRNAs in pancreatic ductal adenocarcinoma (PDAC). Methods. Plasma miRNAs were detected by real-time quantitative PCR, and the association with clinicopathologic factors was subsequently performed by univariate and multivariate analyses. Results. Six miRNAs expressed significantly higher in PDAC patients than in normal individuals were identified. Receiver operating characteristic (ROC) curves were constructed. It was evident that miRNA expression associated with PDAC, lymph node metastasis, serosal infiltration, and comprehensive therapy reached significance for overall survival. High miR-196a expression was associated with poor survival (P = 0.001), whereas high miR-210 expression was significantly associated with improved survival (P = 0.003). Multivariate survival analysis indicated that the miR-210 and miR-196a expression signature, lymph node metastasis, and comprehensive therapy were independent factors affecting overall survival. Conclusions. MiRNA expression profile is distinctive in PDAC. Aberrant expression of certain miRNAs was remarkably involved in shaping the overall survival time, which include miR-196a overexpression and decreased miR-210 expression.

Use of Mature miRNA Strand Selection in miRNAs Families in Cervical Cancer Development

Aberrant miRNA expression is well recognized as a cancer hallmark, nevertheless miRNA function and expression does not always correlate in patients tissues and cell lines studies. In addition to this issue, miRNA strand usage conduces to increased cell signaling pathways modulation diversifying cellular processes regulation. In cervical cancer, 20 miRNA families are involved in carcinogenesis induction and development to this moment. These families have 5p and 3p strands with different nucleotide (nt) chain sizes. In general, mature 5p strands are larger: two miRNAs of 24 nt, 24 miRNAs of 23 nt, 35 miRNAs of 22 nt and three miRNAs of 21 nt. On the other hand, the 3p strands lengths observed are: seven miRNAs of 23 nt, 50 miRNAs of 22 nt, six miRNAs of 21 nt and four miRNAs of 20 nt. Based on the analysis of the 20 miRNA families associated with cervical cancer, 67 3p strands and 65 5p strands are selected suggesting selectivity and specificity mechanisms regulating cell processes like proliferation, apoptosis, migration, invasion, metabolism and Warburg effect. The insight reviewed here could be used in the miRNA based therapy, diagnosis and prognosis approaches.

Upregulation of kazrin F by miR-186 suppresses apoptosis but promotes epithelial-mesenchymal transition to contribute to malignancy in human cervical cancer cells

Objective

Previous studies have identified that kazrin is a constituent of desmosome and influences intercellular adhesion, growing development and morphology. We previously cloned another new isoform, kazrin F and found that it has anti-apoptotic effects on human glioma cell line. To further explore whether kazrin F is involved in tumorigenesis, we investigated its expression and role in cervical cancer (CC) cells.

Methods

The role of kazrin F and miR-186 in CC was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, colony formation, transwell, and apoptosis assays. Using enhanced green fluorescent protein (EGFP) reporter assays, reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and western blot analysis, we identified kazrin F post-transcriptional regulation by miR-186.

Results

We demonstrate that kazrin F is highly expressed in CC tissues compared with the adjacent noncancerous tissues and promotes cell proliferation, colony formation, migration and invasion in HeLa and C33A cells by suppressing apoptosis and facilitating epithelial-to-mesenchymal transition (EMT). Furthermore, miR-186 was confirmed as a regulator of kazrin F dysregulation. An EGFP reporter assay proved that miR-186 directly targets the 3’-untranslated region (3’UTR) of kazrin F and downregulates its expression, and miR-186 expression showed an inverse correlation with kazrin F levels in CC tissues. In addition, overexpression of miR-186 suppressed the malignant behaviors of CC cells. The ectopic expression of kazrin F rescued the inhibitory effects of miR-186.

Conclusions

Our findings indicate that the upregulation of kazrin F due to downregulated miR-186 levels contributes to malignancy, and highlight the significance of kazrin F in CC tumorigenesis.

Deregulated miRNAs in human cervical cancer: functional importance and potential clinical use

Cervical cancer (CC) is one of the most common malignancies affecting women worldwide. While the morbidity and mortality associated with CC are decreasing in western countries, they both remain high in developing countries. Unfortunately, many issues about molecular mechanisms of CC are not clear yet. miRNAs are a group of small noncoding RNAs that could post-transcriptionally modulate the expression of specific genes and participate in the initiation and progression of multiple diseases including CC. In the last decade, mounting evidences suggest an association between miRNAs and human papillomavirus infection, as well as variations in biologic behavior, treatment response and prognosis in CC. Herein, we highlight the latest findings in this area and the potential applications.

Current Technologies and Recent Developments for Screening of HPV-Associated Cervical and Oropharyngeal Cancers

Mucosal infection by the human papillomavirus (HPV) is responsible for a growing number of malignancies, predominantly represented by cervical cancer and oropharyngeal squamous cell carcinoma. Because of the prevalence of the virus, persistence of infection, and long latency period, novel and low-cost methods are needed for effective population level screening and monitoring. We review established methods for screening of cervical and oral cancer as well as commercially-available techniques for detection of HPV DNA. We then describe the ongoing development of microfluidic nucleic acid-based biosensors to evaluate circulating host microRNAs that are produced in response to an oncogenic HPV infection. The goal is to develop an ideal screening platform that is low-cost, portable, and easy to use, with appropriate signal stability, sensitivity and specificity. Advances in technologies for sample lysis, pre-treatment and concentration, and multiplexed nucleic acid detection are provided. Continued development of these devices provides opportunities for cancer screening in low resource settings, for point-of-care diagnostics and self-screening, and for monitoring response to vaccination or surgical treatment.

microRNA-34a-Upregulated Retinoic Acid-Inducible Gene-I Promotes Apoptosis and Delays Cell Cycle Transition in Cervical Cancer Cells

The function of retinoic acid-inducible gene-I (RIG-I) in viral replication is well documented, but its function in carcinogenesis and malignancies as well as relationship with microRNAs (miRNAs) remain poorly understood. miR-34a is an antioncogene in multiple tumors. In our study, RIG-I and miR-34a suppressed cell growth, proliferation, migration, and invasion in cervical cancer cells in vitro. miR-34a was validated as a new regulator of RIG-I by binding to its 3' untranslated region and upregulating its expression level. Furthermore, we revealed that RIG-I and miR-34a enhanced apoptosis, delayed the G1/S/G2 transition of the cell cycle, and inhibited the epithelial-mesenchymal transition process to modulate malignancies in cervical cancer cells. Phenotypic rescue experiments indicated that RIG-I mediates the effects of miR-34a in HeLa and C33A cells. These findings provide new insights into the mechanisms that underlie carcinogenesis and may provide new biomarkers for the diagnosis and therapy of cervical cancer.

Low-Dose Endothelial-Monocyte-Activating Polypeptide-II Induced Autophagy by Down-Regulating miR-20a in U-87 and U-251 Glioma Cells

Preliminary studies have shown that endothelial-monocyte-activating polypeptide-II (EMAP-II) induces autophagy and inhibits the viability of glioma cells via an unknown molecular mechanism. This study explored the possible mechanisms associated with EMAP-II-induced autophagy in glioma cells by regulation of the expression of microRNA-20a (miR-20a). EMAP-II effectively inhibited the viability, migration and invasion of human U-87 and U-251 glioma cells. EMAP-II also up-regulated the expression level of autophagy biomarker microtubule-associated protein one light chain 3 (LC3)-II/I, autophagy related gene ATG7 and ATG5, but down-regulated autophagy substrate P62/SQSTM1 protein expression. The expression levels of miR-20a decreased significantly after U-87 and U-251 cells were treated with EMAP-II. MiR-20a overexpression partly reversed the EMAP-II-induced up-regulation of LC3-II/I and down-regulation of P62/SQSTM1. MiR-20a had a negative regulatory effect on the expression of the proteins ATG7 and ATG5; which were also targets of miR-20a, as detected by a dual-luciferase reporter assay. In addition, both EMAP-II and miR-20a inhibition significantly reduced the viability, migration and invasion of U-87 and U-251 cells, and their combination showed a synergistic effect. Furthermore, nude mice carrying silencing-expressed miR-20a combined with EMAP-II treatment produced the smallest tumors and the highest survival. In summary, low-dose EMAP-II increased expression levels of ATG5 and ATG7 via down-regulation of the expression of miR-20a. This activated the autophagy pathway, thereby significantly inhibiting the viability, migration and invasion of U-87 and U-251 glioma cells. The combined treatment of EMAP-II with a miR-20a inhibitor showed a synergistic effect against glioma.