Differential expression of microRNAs miR-21, miR-31, miR-203, miR-125a-5p and miR-125b and proteins PTEN and p63 in verrucous carcinoma of the head and neck

How MicroRNAs Command the Battle against Cancer

MicroRNAs (miRNAs) are small RNA molecules that regulate more than 30% of genes in humans. Recent studies have revealed that miRNAs play a crucial role in tumorigenesis. Large sets of miRNAs in human tumors are under-expressed compared to normal tissues. Furthermore, experiments have shown that interference with miRNA processing enhances tumorigenesis. Multiple studies have documented the causal role of miRNAs in cancer, and miRNA-based anticancer therapies are currently being developed. This review primarily focuses on two key points: (1) miRNAs and their role in human cancer and (2) the regulation of tumor suppressors by miRNAs. The review discusses (a) the regulation of the tumor suppressor p53 by miRNA, (b) the critical role of the miR-144/451 cluster in regulating the Itch-p63-Ago2 pathway, and (c) the regulation of PTEN by miRNAs. Future research and the perspectives of miRNA in cancer are also discussed. Understanding these pathways will open avenues for therapeutic interventions targeting miRNA regulation.

Epidemiological, clinical and oncological outcomes of laryngeal verrucous carcinomas: a systematic review

OBJECTIVE

To investigate epidemiological, clinical and oncological outcomes of patients with laryngeal verrucous carcinomas (LVC).

METHODS

Two independent authors investigated PubMed, Scopus and Cochrane Library for studies dedicated to epidemiological, clinical and oncological outcomes of patients with LVC. The following outcomes were investigated with PRISMA criteria: age; gender; tobacco/alcohol consumption; HPV infection; anatomical, pathological, therapeutic and survival outcomes. Studies were analyzed for bias through a validated clinical tool.

RESULTS

Of the 212 identified articles, 15 retrospective studies and one prospective uncontrolled study met our inclusion criteria. Three studies reported findings from national databases. The males/females ratio is 9/1. Mean age was 60.3 years, which was younger compared to other laryngeal malignancies. The alcohol, cigarette overuse and the HPV status of patients were lacking in most studies. Glottis and supraglottis were the most common anatomical locations, corresponding to 78.7% and 12.4% of cases, respectively. The main therapeutic approaches consisted of surgery, radiotherapy, surgery followed by radiotherapy. Treatments reported 5-year overall survival and disease-specific survival of 86.3 and 90.8, respectively. The 5- and 10-year local control rate were 83.6 and 72.6, respectively. The 10-year disease-specific survival was 80.2. Heterogeneity between studies was found for inclusion criteria, comorbidity data, and treatments.

CONCLUSION

LVC is a rare laryngeal cancer associated with better survival and recurrence outcomes than laryngeal squamous cell carcinoma. The role of radiotherapy in the treatment regimen needs to be investigated in future prospective controlled studies.

Oral verrucous carcinoma: a diagnostic and therapeutic challenge

BACKGROUND

Verrucous carcinoma is a low-grade variant of squamous cell carcinoma with specific morphologic, cytokinetic and clinical features. Despite low mitotic activity and slow growth, it can infiltrate adjacent tissues in advanced stages but does not metastasize. The most frequently affected site is the oral cavity. The following article provides latest updates in the etiology, clinical presentation, diagnostics and treatment options in oral verrucous carcinoma and discusses the existing dilemmas linked to this unique malignancy.

CONCLUSIONS

Oral verrucous carcinoma must be differentiated from conventional squamous cell carcinoma due to its less aggressive behaviour with a more favourable prognosis. Close communication between clinician and pathologist is mandatory for making a correct diagnosis. Primary surgery with negative surgical margins seems to be the most successful treatment. However, management recommendations are not uniform since they are mostly based on case reports and small retrospective case series. Prospective and pooled multi-institutional studies are therefore needed.

Promising Biomarkers in Head and Neck Cancer: The Most Clinically Important miRNAs

Head and neck cancers (HNCs) comprise a heterogeneous group of tumors that extend from the oral cavity to the upper gastrointestinal tract. The principal etiologic factors for oral tumors include tobacco smoking and alcohol consumption, while human papillomavirus (HPV) infections have been accused of a high incidence of pharyngeal tumors. Accordingly, HPV detection has been extensively used to categorize carcinomas of the head and neck. The diverse nature of HNC highlights the necessity for novel, sensitive, and precise biomarkers for the prompt diagnosis of the disease, its successful monitoring, and the timely prognosis of patient clinical outcomes. In this context, the identification of certain microRNAs (miRNAs) and/or the detection of alterations in their expression patterns, in a variety of somatic fluids and tissues, could serve as valuable biomarkers for precision oncology. In the present review, we summarize some of the most frequently studied miRNAs (including miR-21, -375, -99, -34a, -200, -31, -125a/b, -196a/b, -9, -181a, -155, -146a, -23a, -16, -29, and let-7), their role as biomarkers, and their implication in HNC pathogenesis. Moreover, we designate the potential of given miRNAs and miRNA signatures as novel diagnostic and prognostic tools for successful patient stratification. Finally, we discuss the currently ongoing clinical trials that aim to identify the diagnostic, prognostic, or therapeutic utility of miRNAs in HNC.

miRNA for the assessment of lymph node metastasis in patients with oral squamous cell carcinoma: Systematic review and metanalysis

BACKGROUND

miRNA is one of the advanced epigenetic molecular markers correlating with lymph node metastasis in patients with Oral squamous cell carcinoma (OSCC). Numerous published papers are showing correlation of miRNA with metastasis. There is a need to analyze and validate such correlation.

METHOD

English language literature in major databases from the last 20 years was searched using controlled vocabulary and keywords. Strict inclusion and exclusion criteria were followed for selection of studies. The quality assessment was done as per the QUADAS tool 2 by three independent reviewers. The metanalysis was performed by using random effect model. Standardized mean difference (SMD) was considered as the effect measure. Statistical software used was STATA version 13.1.

RESULTS

With all inclusion and exclusion criteria, eight studies could qualify for metanalysis. The pooled estimate is found to be 0.13 (-0.35, 0.62), P = .585, which is statistically not significant. This indicates that there is a no significant difference in the fold change between metastasis and no metastasis groups. P-value of chi-square statistic for heterogeneity is <.001 (significant), and I-squared statistic is 87.2%, which indicates that heterogeneity is present to a considerable extent. Egger's test shows there is no publication bias involved (P = .819).

CONCLUSION

The metanalysis showed no significant difference in the fold change of miRNA expression between metastasis and non-metastasis OSCC patients. Future studies can be directed to eliminate the heterogeneity among the studies noted in this analysis to confirm the role of miRNA for assessment of regional metastasis with special focus on tongue squamous cell carcinoma.

Identification of Prognosis Associated microRNAs in HNSCC Subtypes Based on TCGA Dataset

Background and Objectives: Head and Neck Squamous Cell Carcinoma (HNSCC) includes cancers from the oral cavity, larynx, and oropharynx and is the sixth-most common cancer worldwide. MicroRNAs are small non-coding RNAs for which altered expression has been demonstrated in pathological processes, such as cancer. The objective of our study was to evaluate the different expression profile in HNSCC subtypes and the prognostic value that one or several miRNAs may have. Materials and Methods: Data from The Cancer Genome Atlas Program-Head and Neck Squamous Cell Carcinoma (TCGA-HNSCC) patients were collected. Differential expression analysis was conducted by edge R-powered TCGAbiolinks R package specific function. Enrichment analysis was developed with Diana Tool miRPath 3.0. Kaplan-Meier survival estimators were used, followed by log-rank tests to compute significance. Results: A total of 127 miRNAs were identified with differential expression level in HNSCC; 48 of them were site-specific and, surprisingly, only miR-383 showed a similar deregulation in all locations studied (tonsil, mouth, floor of mouth, cheek mucosa, lip, tongue, and base of tongue). The most probable affected pathways based on miRNAs interaction levels were protein processing in endoplasmic reticulum, proteoglycans in cancer (p < 0.01), Hippo signaling pathway (p < 0.01), and Transforming growth factor-beta (TGF-beta) signaling pathway (p < 0.01). The survival analysis highlighted 38 differentially expressed miRNAs as prognostic biomarkers. The miRNAs with a greater association between poor prognosis and altered expression (p < 0.001) were miR-137, miR-125b-2, miR-26c, and miR-1304. Conclusions: In this study we have determined miR-137, miR-125b-2, miR-26c, and miR-1304 as novel powerful prognosis biomarkers. Furthermore, we have depicted the miRNAs expression patterns in tumor patients compared with normal subjects using the TCGA-HNSCC cohort.

Downregulation of miR-125b-5p and Its Prospective Molecular Mechanism in Lung Squamous Cell Carcinoma

Background: To explore the clinical significance of miR-125b-5p and its potential mechanisms in lung squamous cell carcinoma (LUSC). Materials and Methods: An integrated analysis of data from in-house quantitative real-time polymerase chain reaction (qRT-PCR), microRNA-sequencing, and microarray assays to appraise the expression level of miR-125b-5p in LUSC tissues compared to adjacent noncancerous controls. The authors identified the candidate targets of miR-125b-5p and conducted functional analysis using computational biology strategies from gene ontology, the Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, disease ontology (DO), and protein-protein interaction (PPI) network analyses to investigate the prospective mechanisms. Results: According to qRT-PCR results, the expression level of miR-125b-5p was markedly decreased in LUSC tissues compared to noncancerous control tissues. Receiver operating characteristic and summary receiver operating characteristic analyses showed that miR-125b-5p had good specificity and sensitivity for distinguishing LUSC tissue from noncancerous lung tissue. The standard mean difference revealed that men and women with lower expression levels of miR-125b-5p may have a higher risk for LUSC. KEGG analysis and DO analysis intimated that target genes were evidently enriched in pyrimidine metabolism and pancreatic carcinoma. The PPI network of the top assembled KEGG pathway indicated that RRM2, UMPS, UCK2, and CTPS1 were regarded as crucial target genes for miR-125b-5p, and RRM2 was eventually deemed a key target. Conclusions: The authors' findings implicate a low expression level of miR-125b-5p in LUSC. A tumor-suppressive role of miR-125b-5p is proposed, based on its effects on LUSC tumor growth, clinical stage progression, and lymph node metastasis.

microRNA-21 regulates the proliferation of placental cells via FOXM1 in preeclampsia

The present study determined the expression of microRNA (miRNA or miR)-21 and forkhead box M1 (FOXM1) in placenta and blood samples from patients with preeclampsia (PE), and investigated the relationship between miR-21 and FOXM1. A total of 32 pregnant women with PE and 28 healthy pregnant women were included in the study as the experimental and control groups, respectively. Placental tissues and peripheral blood were collected from all subjects. ELISA was performed to measure the level of FOXM1 protein in the blood. HTR8/SVneo cells overexpressing miR-21 were established by transfection with agomiR-21. Reverse transcription-quantitative PCR was performed to measure the expression of FOXM1 mRNA and miR-21 in the placenta, blood and cells, and western blotting was used to evaluate FOXM1 protein expression in the placenta. An MTT assay was also performed to assess cell viability. In addition, a dual-luciferase reporter assay was used to investigate the direct interaction between FOXM1 and miR-21. The occurrence of PE was found to be associated with reduced FOXM1 mRNA levels, and elevated FOXM1 protein expression may serve a regulatory role that when attenuated leads to the occurrence of PE. Furthermore, miR-21 may serve a regulatory role in the pathology of PE by downregulating FOXM1 expression at the transcriptional level. In HTR8/SVneo cells, the overexpression of miR-21 reduced cell viability, possibly via the reduction of FOXM1 expression. The dual-luciferase assay indicated that miR-21 directly binds to the 3'-untranslated region of FOXM1 to regulate its expression. The present study demonstrated that the expression of FOXM1 mRNA and protein is downregulated, whereas the expression of miR-21 is upregulated in the placenta and blood samples of PE patients. In conclusion, miR-21 may regulate placental cell proliferation via its effects on FOXM1 to promote the occurrence and development of PE.

Tissue microRNAs in non-small cell lung cancer detected with a new kind of liquid bead array detection system

Background

Commonly used miRNA detection methods cannot be applied for high-throughput analyses. However, this study was aimed to performed a liquid bead array detection system (LBAS) to detect tissue 6 miRNAs in non-small cell lung cancer (NSCLC).

Methods

In this study, evaluation of LBAS was performed to observe the precision, specificity, limitation and stability. Then, a total of 52 primary NSCLC patients who received resection operation without preoperative radiotherapy and chemotherapy between June 2013 and March 2014 were selected, and then the total RNA of the tissues were extracted. We prepared six NSCLC-related miRNAs for LBAS. After optimization and evaluation, LBAS was verified by detecting the relative expression levels of 6 microRNAs in the pathological tissues and corresponding normal tissues of 52 NSCLC patients.

Results

The results of evaluation of LBAS showed that the Mean Fluorescence Intensity (MFI) of the reaction only added with chimeric probes and beads showed no significant change after 180 days (P > 0.05). And the intra-assay Coefficient of Variation (CV) was between 1.57 and 3.5%, while the inter-assay CV was between 4.24 and 11.27%, indicating this system was ideal for diagnostic reagents. In addition, only the beads corresponding to the additional miRNAs showed high MFIs from 8426 to 18,769, whereas the fluorescence values of the other beads were under background levels (MFIs = 20 to 55) in each reaction, indicating no cross reactivity among the miRNAs. The limit of detection of miR-21, miR-210, miR-125b, miR-155, miR-375, and miR-31 were 5.27, 1.39, 1.85, 2.01, 1.34, and 2.73 amol/μL, respectively, showing that the lowest detection limit of miRNA by this system was under pM level. Then, the relative expression levels of miR-21, miR-210, miR-125b, miR-155, miR-375, and miR-31 by using this system were significantly correlated with NSCLC (P < 0.05). And the results of AUC method indicated that specific of the LBAS system was 94.2%.

Conclusions

Our findings suggest that LBAS was simple, high-throughput, and freely combined with absolute quantification. Thus, this system could be applied for tumor miRNAs detection.

miR-31-5p Is a Potential Circulating Biomarker and Therapeutic Target for Oral Cancer

MicroRNAs have been proposed as novel biomarkers for the diagnosis and treatment of many types of cancer. The levels of five candidate microRNAs (miRNAs) (miR-99a-5p, miR-31-5p, miR-138-5p, miR-21-5p, and miR-375-3p) in sera from oral cancer patients and paired tumor and normal tissues were detected by real-time qPCR. The diagnostic power of these miRNAs was analyzed by receiver operating characteristic (ROC) curves. Patient-derived xenograft (PDX) models of oral cancer were established and utilized to verify the potential therapeutic effect of miR-31-5p. Candidate miRNAs were screened from our previous studies and verified in 11 paired oral cancer and adjacent normal tissues. Only serum miR-31-5p levels were significantly different between oral cancer patients and healthy controls and between pre- and postoperative patients. Based on the logistic regression model, this panel of five miRNAs distinguished oral cancer patients from healthy control, with an area under the ROC curve (AUC) of 0.776 (sensitivity = 76.8% and specificity = 73.6%). Furthermore, a miR-31-5p mimic enhanced the proliferation of normal epithelial cells, and antagomiR-31-5p inhibited the proliferation of oral cancer cells in vitro. In vivo, antagomiR-31-5p significantly inhibited tumor growth in oral cancer PDX models. Our findings suggest that circulating miR-31-5p might act as an independent biomarker for oral cancer diagnosis and could serve as a therapeutic target for oral cancer.

A microRNA‑125a variant, which affects its mature processing, increases the risk of radiation‑induced pneumonitis in patients with non‑small‑cell lung cancer

The present study aimed to investigate the role of microRNA (miR)‑125a in the development of pneumonitis inpatients with non‑small‑cell lung cancer that received radiotherapy. In addition, the study aimed to determine how the miR‑125a affects its target, transforming growth factor β (TGFβ). Bioinformatics tools were used to identify a potential miR‑125a binding site in the 3'untranslated region of TGFβ, which was subsequently confirmed using a dual‑luciferase reporter system. In addition, tissue samples were collected from patients with lung cancer and genotyped as CC (n=36), CT (n=28) or TT (n=6). The expression levels of miR‑125a and TGFβ in these samples were determined, and CC genotype samples demonstrated upregulated miR‑125a expression, and downregulated TGFβ protein and mRNA expression compared with samples carrying the minor allele, T. To further investigate the association between the rs12976445 polymorphism and the risk of pneumonitis in patients with lung cancer that received radiotherapy, 534 lung cancer patients diagnosed with pneumonitis and 489lung cancer patients without pneumonitis were recruited. rs12976445 was shown to be significantly associated with the risk of pneumonitis. In conclusion, the rs12976445 polymorphism increased expression levels of TGFβ by decreasing the expression of miR‑125a, and therefore may be associated with the development of pneumonitis in patients with lung cancer that receive radiotherapy.

Aberrantly expressed genes and miRNAs in human hypopharyngeal squamous cell carcinoma based on RNA‑sequencing analysis

The aim of the present study was to investigate the key genes, miRNAs and pathways in hypopharyngeal squamous cell carcinoma (HPSCC) and to elucidate the mechanisms underlying HPSCC development. The gene and microRNA (miRNA) expression profiles of HPSCC tissues and adjacent normal tissues from three subjects were obtained. Differentially expressed genes (DEGs) and differentially expressed miRNAs were identified in HPSCC. Functional annotation and protein-protein interaction (PPI) network were conducted to elucidate the biological functions of DEGs. A total of 160 DEGs (16 upregulated and 144 downregulated genes) and 79 differentially expressed miRNAs (48 upregulated and 31 downregulated miRNAs) were identified in HPSCC. The deregulated genes were significantly involved in spliceosome, cell cycle and RNA degradation. In the PPI network, S-phase kinase associated protein 1 (SKP1), non-POU domain containing octamer binding (NONO) and zinc activated ion channel (ZACN) were identified as hub proteins. On the whole, the present study may help to gain a comprehensive understanding of tumorigenesis in HPSCC and provide valuable information for early diagnosis and drug design of HPSCC in future research.

Clinicopathological significance of miR-26, miR-107, miR-125b, and miR-203 in head and neck carcinomas

OBJECTIVES

MicroRNAs play a role in the development and progression of head and neck squamous cell carcinomas (HNSCC). Our aim was to study the expression of miR-26, miR-107, miR-125b, and miR-203 in primary HNSCC with and without lymph node metastasis and their clinicopathological significance.

MATERIALS AND METHODS

The expression of microRNAs in primary HNSCC with lymph node metastasis (n = 16) and their matched lymph node, as well as primary tumors without metastasis (n = 16), were determined by quantitative RT-PCR and analyzed with clinicopathological features and survival.

RESULTS

The expression levels of miR-26 (p < .05) and miR-125b (p < .01) were higher in metastatic primary HNSCC, while levels of miR-203 (p < .01) were lower. The expression of the microRNAs was associated with clinicopathological features, including miR-26 high expression and N stage (p = .04), poor differentiation (p = .005) and recurrence (p = .007), miR-125b high expression and N stage (p = .0005) and death (p = .02), and low levels of miR-203 and N stage (p = .04). The high expression of miR-26 was associated with shortened disease-free survival, and high miR-125b expression was an independent risk factor for poor disease-specific survival.

CONCLUSIONS

These findings suggest that miR-26 and miR-125b may be associated with the progression and metastasis of HNSCC and that miR-203 is associated with a more favorable prognosis.

ΔNp63α and microRNAs: leveraging the epithelial-mesenchymal transition

The epithelial-mesenchymal transition (EMT) is a cellular reprogramming mechanism that is an underlying cause of cancer metastasis. Recent investigations have uncovered an intricate network of regulation involving the TGFβ, Wnt, and Notch signaling pathways and small regulatory RNA species called microRNAs (miRNAs). The activity of a transcription factor vital to the maintenance of epithelial stemness, ΔNp63α, has been shown to modulate the activity of these EMT pathways to either repress or promote EMT. Furthermore, ΔNp63α is a known regulator of miRNA, including those directly involved in EMT. This review discusses the evidence of ΔNp63α as a master regulator of EMT components and miRNA, highlighting the need for a deeper understanding of its role in EMT. This expanded knowledge may provide a basis for new developments in the diagnosis and treatment of metastatic cancer.

Intraindividual variation of microRNA expression levels in plasma and peripheral blood mononuclear cells and the associations of these levels with the pathogenesis of autoimmune thyroid diseases

Background:

microRNAs (miRNAs) circulate in the blood and negatively regulate the expression of mRNAs. Some miRNAs are associated with the development of autoimmune thyroid diseases (AITD); however, there are few reports on the association between miRNA expression and the pathogenesis of AITD or the physiological variations of circulating miRNAs, which are important to examine as biomarkers.

Methods:

We examined the circadian and day-to-day variations in the expression levels of 5 miRNAs (miR-125a, miR-146a, miR-155, let-7e and miR-106a) in plasma and peripheral blood mononuclear cells (PBMC). We also analysed the expression levels of two of these miRNAs (miR-146a and miR-155) in 20 healthy controls, 60 Graves’ disease (GD) patients and 50 Hashimoto’s disease (HD) patients.

Results:

For each miRNA, we observed wide intraindividual variation [coefficient of variation value (CV): 70%–100%] compared to measurement error (CV: 20%–40%). In patients with AITD, HD, GD in remission and mild HD, the expression levels of miR-146a in PBMC were increased 296%, 328%, 348% and 464% above the levels in healthy controls, respectively (p=0.0443 and p=0.0273, p=0.0267 and p=0.0052, respectively). In severe HD, the expression level of miR-155 in plasma was increased to 347% of that in healthy controls (p=0.0256).

Conclusions:

The expression levels of miRNAs in plasma and PBMC showed wide intraindividual variation. In addition, miR-146a may be associated with the development of AITD.

Diagnostic Biomarkers in Oral Verrucous Carcinoma: A Systematic Review

Oral verrucous carcinoma (OVC), a low-grade variant of oral squamous cell carcinoma (OSCC), is most frequently seen in the oral cavity. No clear etiology has been found for this lesion, but human papilloma virus, chewing betel nuts, and ultraviolet radiation are suggested as probable causes. Differential diagnosis of OVC is challenging for oral pathologists. The aim of this study was to review the molecular-based approaches for differential diagnosis of OVC. An electronic search was conducted in Medline and Scopus from January 2004 to July 2015 limited to English language publications. Published papers on verrucous carcinoma (VC) were found according to the inclusion and exclusion criteria and analyzed qualitatively. Data extraction were performed according to PRISMA statement. A total of 423 articles were reviewed; out of which, 26 articles completely fulfilled the inclusion criteria. Most of the included studies investigated proliferative and apoptotic biomarkers such as p53 and Ki67. No definite conclusion was drawn for cytoskeletal biomarkers due to variability of factors and lack of significant expression. However, it seems that cytokeratin10 (CK 10) can be useful for differentiation of OVC and benign squamous lesions. Among cell surface and extracellular matrix biomarkers tissue biomarkers, matrix metalloproteinase (MMP)-2, -9, CD31 and CD68 seem to be useful for differentiation of OVC and OSCC and glucose transporter-1 (GLUT-1) can help in differentiation of OVC from oral epithelial dysplasia. Differences among OVC, OSCC and normal epithelium in expression profiles of the investigated biomarkers help in their differential diagnosis; although, clinicohistopathological similarities among verrucous hyperplasia, noninvasive OVC and invasive well-differentiated OSCC make the diagnosis difficult. Further studies are required to better differentiate these oral lesions.

Oral verrucous carcinoma: From multifactorial etiology to diverse treatment regimens (Review)

Oral verrucous carcinoma (OVC) is a verrucous variant of oral squamous cell carcinoma (OSCC), which accounts for 2-12% of all oral carcinomas with a 5-year survival rate of only approximately 50%. Enormous effort has been dedicated to this cancer, and the past decades have witnessed significant advances in relevant diagnostic and therapeutic approaches. Currently, there exist three challenges from primary sub-fields of research and clinical practice of the cancer, namely multifactorial etiology, complex molecular mechanism, and deficient treatment. This study reviews the existing literature on the cancer, encompassing its etiology, clinical manifestations and pathology, molecular mechanism, diagnosis and differential diagnosis, and treatment. For improved treatment of OVC, multifactorial etiology analysis, incorporation of effective biomarkers for mechanism illustration, and integration of multidisciplinary modalities are expounded, in an attempt to resolve the challenges and to provide a useful guide for future research in the field.

MicroRNA-125a-5p modulates human cervical carcinoma proliferation and migration by targeting ABL2

Background

In this study, we intended to understand the regulatory mechanisms of microRNA-125a-5p (miR-125a-5p) in human cervical carcinoma.

Methods

The gene expressions of miR-125a-5p in seven cervical carcinoma cell lines and 12 human cervical carcinoma samples were evaluated by quantitative real-time reverse transcription polymerase chain reaction. Ca-Ski and HeLa cells were transduced with lentivirus carrying miR-125a-5p mimics, and the effects of lentivirus-induced miR-125a-5p upregulation on cervical carcinoma proliferation and migration were examined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and transwell assays, respectively. In additional, HeLa cells were inoculated into null mice to evaluate the effect of miR-125a-5p upregulation on in vivo cervical carcinoma growth. The direct regulation of miR-125a-5p on its target gene, ABL proto-oncogene 2 (ABL2), in cervical carcinoma was evaluated by quantitative real-time reverse transcription polymerase chain reaction, Western blotting and luciferase reporter assays, respectively. ABL2 was then downregulated by small interfering RNA to examine its effect on cervical carcinoma proliferation and migration.

Results

miR-125a-5p was downregulated in both cervical carcinoma cell lines and human cervical carcinomas. In Ca-Ski and HeLa cells, lentivirus-mediated miR-125a-5p upregulation inhibited cancer proliferation and migration in vitro and cervical carcinoma transplantation in vivo. ABL2 was shown to be directly targeted by miR-125a-5p. In cervical carcinoma, ABL2 gene and protein levels were both downregulated by miR-125a-5p. Small interfering RNA-mediated ABL2 downregulation also had tumor-suppressive effects on cervical carcinoma proliferation and migration.

Conclusion

The molecular pathway of miR-125a-5p/ABL2 plays an important role in human cervical carcinoma. Targeting miR-125a-5p/ABL2 pathway may provide a new treatment strategy for patients with cervical carcinoma.

miR-19a and SOCS-1 expression in the differential diagnosis of laryngeal (glottic) verrucous squamous cell carcinoma

BACKGROUND

Laryngeal verrucous squamous cell carcinoma (VSCC) is a highly differentiated squamous cell carcinoma (SCC), the diagnosis of which can meet with many pitfalls: benign hyperplastic lesions and conventional SCC are the most important differential diagnoses. The microRNA miR-19a is overexpressed in many solid tumours and regulates the suppressor of cytokine signalling-1 (SOCS-1) expression.

AIMS

The main endpoints were to assess miR-19a and SOCS-1 expression in glottic VSCC, and the former's potential role in differentiating between glottic VSCC, conventional SCC and hyperplastic lesions.

METHODS

The expression of MiR-19a (by reverse transcription and quantitative real-time PCR) and SOCS-1 (by immunohistochemistry, rabbit polyclonal anti-SOCS-1 antibody) was assessed in 11 consecutive cases of glottic VSCC, 20 of papillary hyperplasia and 42 cases of conventional SCC.

RESULTS

Mean miR-19a expression was significantly higher (p = 0.000) in malignant glottic lesions (conventional SCC/VSCC) than in benign conditions. Significant differences in mean miR-19a expression also emerged between conventional SCC and papillary hyperplasia (p = 0.000), and between conventional SCC and VSCC (p = 0.03). miR-19a expression was not statistically associated with SOCS-1 immunoreactivity or immunostaining intensity in VSCC, conventional SCC or papillary hyperplasia.

CONCLUSIONS

Our preliminary outcomes suggest the utility of miR-19a in the challenging differential diagnosis of laryngeal VSCC. Although miR-19a has been found to regulate SOCS-1 expression, this evidence was not confirmed by this investigation.

Function and clinical potential of microRNAs in hepatocellular carcinoma

MicroRNAs (miRNAs) are small non-coding RNAs involved in the initiation and progression of several types of human cancer, including hepatocellular carcinoma (HCC), which is one of the most common types of cancer and the third leading cause of cancer-related mortality worldwide. Mounting evidence has demonstrated that miRNAs play a vital role in HCC, hepatitis, alcoholic liver disease, liver cell development and the metabolic functions of the liver. The aim of the present review was to summarize the most recent findings on the functions of miRNAs in the liver and discuss their potential roles in the diagnosis, prognosis and treatment of HCC.

The potential role of microRNA-31 expression in early colorectal cancer

The expression of microRNA-31 (miR-31) has been implicated in the progression of some human malignancies including colorectal cancer. However, the clinical significance of the expression of miR-31 in submucosally invasive (T1) colorectal cancer remains unclear. The aim of the present study was to delineate the relationship between clinicopathological features and the oncogenic modulator miR-31 in submucosally invasive colorectal cancer. We investigated the expression of miR-31 in 50 submucosally invasive colorectal cancer specimens, along with the corresponding non-tumoral mucosa specimens, using a real-time quantitative reverse transcription-polymerase chain reaction (qRT-PCR). The relationships between miR-31 expression levels and clinicopathological characteristics were assessed. The miR-31 host gene locus was investigated using fluorescence in situ hybridization. qRT-PCR revealed that the expression of miR-31 was higher in colorectal cancer tissue than in non-tumoral tissue (P = 0.0002). The up-regulated expression of miR-31 may play an oncogenic role in the early stage of carcinogenesis in colorectal cancers.

Gene and miRNA expression changes in squamous cell carcinoma of larynx and hypopharynx

Laryngo-pharyngeal squamous cell carcinomas are one of the most common head and neck cancers. Despite the presence of a large body of information, molecular biomarkers are not currently used in the diagnosis, treatment and management of patients for this group of cancer. Here, we have profiled expression of genes and microRNAs of larynx and hypopharynx tumors using high-throughput sequencing experiments. We found that matrix metalloproteinases along with SCEL, CRNN, KRT4, SPINK5, and TGM3 among others have significantly altered expression in these tumors. Alongside gene expression, the microRNAs hsa-miR-139, hsa-miR-203 and the hsa-miR-424/503 cluster have aberrant expression in these cancers. Using target genes for these microRNAs, we found the involvement of pathways linked to cell cycle, p53 signaling, and viral carcinogenesis significant (P-values 10(-13), 10(-9) and 10(-7) respectively). Finally, using an ensemble machine-learning tool, we discovered a unique 8-gene signature for this group of cancers that differentiates the group from the other tumor subsites of head and neck region. We investigated the role of promoter methylation in one of these genes, WIF1, and found no correlation between DNA methylation and down-regulation of WIF1. We validated our findings of gene expression, 8-gene signature and promoter methylation using q-PCR, data from TCGA and q-MSP respectively. Data presented in this manuscript has been submitted to the NCBI Geo database with the accession number GSE67994.

Overexpression of miR-21 promotes the proliferation and migration of cervical cancer cells via the inhibition of PTEN

The oncogenic miR-21 has been widely recognized to promote the development and progression of various types of malignant tumors, but not cervical cancers. The aim of this study was to examine the expression of miR-21 and PTEN in cervical cancer specimens using quantitative PCR. The miR-21 level was then manipulated in the cervical cancer lines and the regulation of miR-21 on the proliferation, migration and invasion of cervical cancer cells was determined. Additionally, we determined the role of PTEN in the miR-21-regulated proliferation, migration and invasion of cervical cancer cells. miR-21 was upregulated in the cervical cancer specimens, negatively correlating with the PTEN mRNA level. Transfection of the miR-21 mimics was markedly promoted, whereas the miR-21 inhibitor suppressed the proliferation, migration and invasion of cervical cancer cells, with a significant inhibition of PTEN expression. In addition, the overexpression of PTEN markedly inhibited the proliferation and migration of the cervical cancer cells. The present study showed the upregulation of miR-21 in invasive cervical cancers, and confirmed the promotion of miR-21 with regard to the proliferation, migration and invasion in cervical cancer cells via inhibiting the PTEN expression. To the best of our knowledge, this is the first study to confirm that the miR-21/PTEN pathway promotes cervical cancer.

Effect of microRNA-203 on tumor growth in human hypopharyngeal squamous cell carcinoma

MicroRNAs (MiRNAs) have been recognized to regulate cancer initiation and progression in carcinogenesis as either oncogenes or tumor suppressor genes, but their role in hypopharyngeal cancer development is not clearly defined. To determine whether miRNA-203 can promote tumor growth in human hypopharyngeal squamous cell carcinoma, we conducted experiments on the functional study of miRNA-203 and identification of miRNA-203 regulated target genes in hypopharyngeal cancer cells. We found that cell proliferation and cell colony-forming increased more in the miRNA-203 up-regulated cancer cells than in the negative control cancer cells. Up-regulation of miRNA-203 accelerated cell cycle progression in hypopharyngeal cancer cells. TP63 and B3GNT5 mRNAs were identified and validated as targets of miRNA-203. However, transwell assay and wound scratch assay showed that miRNA-203 did not involve in invasion and metastasis in hypopharyngeal cancer cells. According to the results, we conclude that miRNA-203 can promote tumor growth in human hypopharyngeal squamous cell carcinoma. These results provide the convincing evidence for the first time that up-regulation of miRNA-203 contributes to the malignancy of hypopharyngeal squamous cell carcinoma, possibly through down-regulating TP63 and B3GNT5.

Associations of single nucleotide polymorphisms in precursor-microRNA (miR)-125a and the expression of mature miR-125a with the development and prognosis of autoimmune thyroid diseases

It is important to search the biomarker to predict the development and prognosis of autoimmune thyroid diseases (AITDs) such as Hashimoto's disease (HD) and Graves' disease (GD). MicroRNA (miR) bind directly to the 3' untranslated region of specific target mRNAs to suppress the expression of proteins, promote the degradation of target mRNAs and regulate immune response. miR-125a is known to be a negative regulator of regulated upon activation normal T cell expressed and secreted (RANTES), interleukin (IL)-6 and transforming growth factor (TGF)-β; however, its association with AITDs remains unknown. To clarify the association between AITDs and miR-125a, we genotyped the rs12976445 C/T, rs10404453 A/G and rs12975333 G/T polymorphisms in the MIR125A gene, which encodes miR-125a, using direct sequencing and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) methods in 155 patients with GD, 151 patients with HD and 118 healthy volunteers. We also examined the expression of miR-125a in peripheral blood mononuclear cells (PBMCs) from 55 patients with GD, 79 patients with HD and 38 healthy volunteers using quantitative real-time PCR methods. We determined that the CC genotype and C allele of the rs12976445 C/T polymorphism were significantly more frequent in patients with HD compared with control subjects (P < 0·05) and in intractable GD compared with GD in remission (P < 0·05). The expression of miR-125a was correlated negatively with age (P = 0·0010) and down-regulated in patients with GD compared with control subjects (P = 0.0249). In conclusion, miR-125a expression in PBMCs and the rs12976445 C/T polymorphism were associated with AITD development and prognosis.

Analysis of MicroRNAs in sputum to improve computed tomography for lung cancer diagnosis

INTRODUCTION

Computed tomography (CT) plays a central role in lung cancer diagnosis. However, CT has relatively low specificity, presenting a challenge in clinical settings. We previously identified 12 microRNAs (miRNAs) whose expressions in tumor tissues were associated with lung cancer.

METHODS

Using quantitative reverse transcriptase polymerase chain reaction, we aimed to identify miRNA biomarkers in sputum that could complement CT for diagnosis of lung cancer.

RESULTS

In a training set consisting of 66 lung cancer patients and 68 cancer-free smokers, 10 of the 12 miRNAs were differentially expressed between the cases and controls (p ≤ 0.01). From the miRNAs, a logistic regression model was built on the basis of miR-31 and miR-210, both of which had the best prediction for lung cancer, producing an area under receiver operating characteristic curve of 0.83. Combined use of the two miRNAs yielded 65.2% sensitivity and 89.7% specificity, CT had 93.9% sensitivity and 83.8% specificity for lung cancer diagnosis. Notably, combined analysis of the miRNA biomarkers and CT produced a higher specificity than does CT used alone (91.2% versus 83.8%; p < 0.05). The diagnostic performance of the biomarkers was confirmed in a testing set comprising 64 lung cancer patients and 73 cancer-free smokers.

CONCLUSION

The sputum miRNA biomarkers might be useful in improving CT for diagnosis of lung cancer, but further independent validation on an external and prospective cohort of patients is required.

Reduced miR-125a-5p expression is associated with gastric carcinogenesis through the targeting of E2F3

Emerging evidence suggests that altered expression of microRNAs (miRNAs) is involved in cancer progression. However, the role of miR-125a-5p in gastric carcinogenesis remains unknown. Quantitative real-time PCR analysis revealed that the expression of miR-125a-5p was significantly decreased in >80% of gastric cancer tissues compared with their adjacent non-tumor tissues, and was markedly reduced in ~95% of intestinal-type gastric cancer tissues. The downregulated miR-125a-5p was significantly associated with gastric cancer metastasis. Ectopic expression of miR-125a-5p substantially inhibited the proliferation, migration and invasion activities of gastric cancer cells. Furthermore, forced expression of miR-125a-5p repressed the activity of a luciferase reporter carrying the 3'-untranslated (3'-UTR) region of E2F3, which was eliminated by mutation of the predicted miR-125a-binding site, indicating that E2F3 may be a potential target gene of miR-125a-5p. These data suggest that by targeting E2F3, miR-125a-5p may be important as a potential tumor suppressor gene in gastric carcinogenesis.

Preliminary analysis of different microRNA expression levels in juvenile angiofibromas

Juvenile angiofibroma (JA) is a rare fibrovascular tumor affecting, almost exclusively, adolescent males. The finding of frequent β-catenin-mutations in JAs emphasized the significance of the Wnt-signaling pathway in tumor pathogenesis. In the last decade, microRNAs (miRNAs or miRs) have been found to be involved in cancer pathogenesis by post-transcriptional regulation of gene expression and have not been analyzed in JAs thus far. In the present study, the expression of 4 miRNAs (hsa-let-7d, hsa-miR-98, hsa-miR-125a-5p and hsa-miR-218) was analyzed in 13 JAs and 3 deepithelized inferior nasal turbinates that were used as control tissue. The miRNA expression of hsa-let-7d (P=0.158) and hsa-miR-98 (P=0.069) was not statistically different between the two tissue types, however, a significant decrease in expression was observed for hsa-miR-125a-5p (P=0.037) and hsa-miR-218 (P=0.009) in JAs compared to inferior nasal turbinates. As downregulation of miRNA 218 has been recently shown to result in stabilization and nuclear accumulation of β-catenin, the present data indicates further evidence for the importance of the Wnt-signaling pathway in JAs.

MicroRNA expression differs in cutaneous squamous cell carcinomas and healthy skin of immunocompetent individuals

Cutaneous squamous cell carcinoma (cSCC) is one of the most common skin cancers, but the influence of microRNA (miRNA) expression has only been sporadically analysed. We hypothesized that miRNAs are differentially expressed in cSCC and hence influence its development. We therefore isolated total miRNA from well-differentiated cSCCs and from controls without SCC. Expression analyses of 12 miRNAs showed three significantly differentially expressed miRNAs. We identified a significant upregulation of the miR-21 and the miR-31, a proto-oncogene like miR-21. While the upregulated expression of miR-21 has been known for some time, the increased expression of miR-31 was never shown so clearly. Furthermore, we showed the upregulation of miRNA-205, which has never been described before. The miR-205 induces specific keratinocyte migration and could be a characteristic marker for cSCC. It has to be determined in following studies whether these upregulated expressions are specific for cSCC and if so, for which cSCC stages.

Verrucous carcinoma of the head and neck - not a human papillomavirus-related tumour?

Association between verrucous carcinoma (VC) of the head and neck and human papillomaviruses (HPV) is highly controversial. Previous prevalence studies focused mostly on α-PV, while little is known about other PV genera. Our aim was to investigate the prevalence of a broad spectrum of HPV in VC of the head and neck using sensitive and specific molecular assays. Formalin-fixed, paraffin-embedded samples of 30 VC and 30 location-matched normal tissue samples were analysed, by using six different polymerase chain reaction-based methods targeting DNA of at least 87 HPV types from α-PV, β-PV, γ-PV and μ-PV genera, and immunohistochemistry against p16 protein. α-PV, γ-PV and μ-PV were not detected. β-PV DNA was detected in 5/30 VC (16.7%) and in 18/30 normal tissue samples (60.0%): HPV-19, -24 and -36 were identified in VC, and HPV-5, -9, -12, -23, -24, -38, -47, -49 and -96 in normal tissue, whereas HPV type was not determined in 2/5 cases of VC and in 6/18 normal tissue samples. p16 expression was detected in a subset of samples and was higher in VC than in normal tissue. However, the reaction was predominantly cytoplasmic and only occasionally nuclear, and the extent of staining did not exceed 75%. Our results indicate that α-PV, γ-PV and μ-PV are not associated with aetiopathogenesis of VC of the head and neck. β-PV DNA in a subset of VC and normal tissue might reflect incidental colonization, but its potential biological significance needs further investigation.

Chemoresistance in ovarian cancer linked to expression of microRNAs

We evaluated the differential expression of several microRNAs (miRNAs) among malignant cells in ascites and matched omental metastasis in patients with epithelial ovarian cancer (EOC). Ascites and omental tumors were collected prospectively from five patients who were undergoing primary surgical cytoreduction. Patient samples were processed and treated with carboplatin, paclitaxel and combination chemotherapy. Cell viability was evaluated and miRNA profiling was performed on both tumor cells from ascites fluid and omental cake. Quantitative real-time PCR (RT-q-PCR) and western blots were used to evaluate expressions of miRNA-21 and miRNA -214 and associated proteins. Malignant cells in ascites showed greater cell viability when treated with carboplatin compared to omental metastasis. A significant up-regulation of miRNA-21 and miRNA-214 was observed in malignant cells of ascites compared to omental metastasis; this was confirmed by both cell viability assay and RT-q-PCR. Ours is the first report that demonstrates significant up-regulation of miRNA-21 and miRNA-214 in tumor cells from ascites of patients with EOC compared to omental metastasis. This finding has important implications for intrinsic carboplatin resistance in these patients.

Control by a hair's breadth: the role of microRNAs in the skin

MicroRNAs have continued to attract enormous interest in the scientific community ever since their discovery. Their allure stems from their unique role in posttranscriptional gene expression control as well as their potential application as therapeutic targets in various disease pathologies. While much is known concerning their general biological function, such as their interaction with RNA-induced silencing complexes, many important questions still remain unanswered, especially regarding their functions in the skin. In this review, we summarize our current knowledge of the role of microRNAs in the skin in order to shine new light on our understanding of cutaneous biology and emphasize the significance of these small, single-stranded RNA molecules in the largest organ of the human body. Key events in epidermal and hair follicle biology, including differentiation, proliferation, and pigmentation, all involve microRNAs. We explore the role of microRNAs in several cutaneous processes, such as appendage formation, wound-healing, epithelial-mesenchymal transition, carcinogenesis, immune response, and aging. In addition, we discuss current trends in research and offer suggestions for future studies.