Identification of prognostic microRNA candidates for head and neck squamous cell carcinoma

Correlation between the miR-618 rs2682818 C>A polymorphism and venous malformation susceptibility

Venous malformations are the most common congenital vascular malformations, and the incidence rate is high. Previous studies have confirmed that a variety of polymorphisms within the miRNA functional region are associated with tumor susceptibility. We examined the correlation between miR-618 rs2682818 C>A and risk of developing venous malformation in a southern Chinese population (1113 patients and 1158 controls). TaqMan genotyping of miR-618 rs2682818 C>A was conducted utilizing real-time fluorescent quantitative PCR. The miR-618 rs2682818 polymorphism was not correlated with susceptibility to venous malformation (CA/AA vs. CC: adjusted odds ratio [AOR] = 1.00, 95% confidence interval [CI] = 0.81-1.25, p = 0.994; AA vs. CC/CA: AOR = 1.10, 95% CI = 0.73-1.65, p = 0.646). Stratified analysis of different subtypes of venous malformation revealed that there was no significant difference in the rs2682818 C>A polymorphism genotypes across these subtypes. Our results indicate that miR-618 rs2682818 C>A polymorphism is not correlated with the susceptibility to venous malformation.

LncRNA-RMST Functions as a Transcriptional Co-regulator of SOX2 to Regulate miR-1251 in the Progression of Hirschsprung's Disease

Hirschsprung's disease (HSCR) is a congenital disorder characterized by the absence of enteric neural crest cells (ENCCs). LncRNA rhabdomyosarcoma 2-associated transcript (RMST) is essential for the growth and development of neuron. This study aimed to reveal the role of RMST in the pathogenesis of HSCR. The expression level of RMST, miR-1251, SOX2, and AHNAK was evaluated with qRT-PCR or western blot. CCK-8 and transwell assays were applied to detect cell proliferation and migration. CHIP and RIP assays were applied to determine the combination relationship between SOX2 and promoter region of miR-1251 or RMST and SOX2, respectively. Dual-luciferase reporter assay was performed to confirm miR-1251 targeted AHNAK. As results have shown, RMST was downregulated in the aganglionic colon of HSCR patients. The knockdown of RMST attenuated cell proliferation and migration significantly. MiR-1251, the intronic miRNA of RMST, was also low expressed in HSCR, but RMST did not alter the expression of miR-1251 directly. Furthermore, SOX2 was found to regulate the expression of miR-1251 via binding to the promoter region of miR-1251, and RMST strengthened this function by interacting with SOX2. Moreover, AHNAK was the target gene of miR-1251, which was co-regulated by RMST and SOX2. In conclusion, our study demonstrated that RMST functioned as a transcriptional co-regulator of SOX2 to regulate miR-1251 and resulted in the upregulation of AHNAK, leading to the occurrence of HSCR. The novel RMST/SOX2/miR-1251/AHNAK axis provided potential targets for the diagnosis and treatment of HSCR during embryonic stage.

Polymorphism rs2682818 participates in the progression of colorectal carcinoma via miR-618-TIMP1 regulatory axis

Colorectal carcinoma (CRC) has a high morbidity and mortality. Current studies have confirmed a variety of microRNA polymorphisms were associated with tumor susceptibility, however, the mechanisms are still unknown. In this study, we were aimed to clarify how polymorphism rs2682818 participated in the progression of CRC. First of all, the differential expression of miR-618 was assessed by quantitative real-time polymerase chain reaction in CRC patients with different genotypes of polymorphism rs2682818, including homozygous (TT) genotype, homozygous (GG) genotype and heterozygous (TG) genotype. Secondly, plasmids carried miR-168 precursor sequences harboring rs2682818 (SNP type) or without rs2682818 (wild type) were transfected into 293T cells to verify that polymorphism rs2682818 affected miR-618 expression. Thirdly, CCK-8 assay, flow cytometry assay, transwell assay and mouse xenograft assay were performed to measure the biological functions of miR-618 in CRC. Fourthly, the candidate target genes of miR-618 which were predicted by bioinformatics tools were verified by luciferase reporter assay. Finally, in order to explain the potential molecular mechanisms, western blotting was performed to demonstrate the differential expression and phosphorylation of pathway related proteins. The results showed that miR-618 was down-regulated in colon cancer, especially in CRC patients with rs2682818 GG homozygous genotype. Higher expression of mature miR-618 occurred in patients with TT homozygous genotype, and these patients usually had a longer survival time. Moreover, miR-618 mimic obviously impaired the growth and invasion ability of CRC cells, and miR-618 mimic also remarkably promoted CRC cell apoptosis. Our luciferase experiments confirmed that TIMP1 was a target of miR-618 in CRC cells. Knockdown of TIMP1 also significantly inhibited the malignant cytological features of CRC, including malignant growth and invasion as well as apoptosis resistance. In summary, polymorphism rs2682818 participated in the progression of CRC via affecting the expression of mature miR-618 in CRC cells, and miR-618 inhibited the progression of CRC via targeting TIMP1expression.

Human microRNA-182-5p and kinectin 1: Potential biomarkers for prognosis in oral squamous cell carcinoma

BACKGROUND

The prognostic impact of hsa-miRNA-182-5p in oral cancer remains unexplored. Therefore, the aim of this study was to investigate the prognostic value of hsa-miRNA-182-5p and its predicted target kinectin 1 (KTN1) in oral squamous cell carcinoma (OSCC).

METHOD

Expression level of hsa-miRNA-182-5p was analyzed in tumor tissue (n = 36) and healthy oral mucosal tissue (n = 17) using quantitative real-time polymerase chain reaction. Protein level of the predicted target KTN1 was detected via immunohistochemistry. Results were validated in a cohort of The Cancer Genome Atlas (TCGA).

RESULTS

After dividing the data into a subgroup with high and low hsa-miRNA-182-5p expression level, a significant better overall (p = 0.016), recurrence-free (p = 0.009), and progression-free survival (p = 0.004) was observed in an upregulation of hsa-miRNA-182-5p. Staining intensity of KTN1 showed a reciprocal impact on the prognosis. Validation in a TCGA cohort confirmed these results.

CONCLUSION

Our results indicate hsa-miRNA-182-5p and KTN1 as potential biomarkers for OSCC.

MicroRNAs hsa-miR-618 and hsa-miR-297 Might Modulate the Pleiotropic Effects Exerted by Statins in Endothelial Cells Through the Inhibition of ROCK2 Kinase: in-silico Approach

Several studies show that statin therapy improves endothelial function by cholesterol-independent mechanisms called “pleiotropic effects.” These are due to the inhibition of the RhoA/ROCK kinase pathway, its inhibition being an attractive atheroprotective treatment. In addition, recent work has shown that microRNAs, posttranscriptional regulators of gene expression, can affect the response of statins and their efficacy. For this reason, the objective of this study was to identify by bioinformatic analysis possible new microRNAs that could modulate the pleiotropic effects exerted by statins through the inhibition of ROCK kinases. A bioinformatic study was performed in which the differential expression of miRNAs in endothelial cells was compared under two conditions: Control and treated with simvastatin at 10 μM for 24 h, using a microarray. Seven miRNAs were differentially expressed, three up and four down. Within the up group, the miRNAs hsa-miR-618 and hsa-miR-297 present as a predicted target to ROCK2 kinase. Also, functional and enriched pathway analysis showed an association with mechanisms associated with atheroprotective effects. This work shows an in-silico approach of how posttranscriptional regulation mediated by miRNAs could modulate the pleiotropic effects exerted by statins on endothelial cells, through the inhibition of ROCK2 kinase and its effects.

Circulating miR-618 Has Prognostic Significance in Patients with Metastatic Colon Cancer

The present study evaluated the prognostic role of circulating miRNA-618 in patients with metastatic colon cancer (mCC) and whether miR-618 gene rs2682818 single nucleotide polymorphisms (SNP) are associated with colon cancer susceptibility and expression levels of mature miR-618. In total, 104 patients with mCC before starting the chemotherapy were investigated. The expression status of circulating miR-618 in mCC was evaluated by quantitative PCR. TaqMan PCR assay was used for rs2682818 SNP genotyping. miR-618 was overexpressed in serum of mCC patients. Patients with high and intermediate expression of miR-618 had a significantly longer mean overall survival (OS) of 21 months than patients with low expression—16 months. In addition, multivariate Cox regression analysis confirmed the association between high/intermediate levels of miRNA-618 and longer OS, HR = 0.51, 95% CI: 0.30–0.86, p = 0.012. miR-618 rs2682818 SNP significantly decreased the risk of colon cancer susceptibility in both heterozygous codominant (AC vs. CC, OR = 0.39, 95% CI: 0.17–0.88, p = 0.024) and overdominant (AC vs. CC + AA, OR = 0.37, 95% CI: 0.16–0.85, p = 0.018) genetic models. Our data suggest that circulating miRNA-618 could be useful as a prognostic biomarker in mCC. Patients harboring AC rs2682818 genotype have a decreased risk for colon cancer in comparison with patients with CC and AA genotypes.

Antioncogenic Effect of MicroRNA-206 on Neck Squamous Cell Carcinoma Through Inhibition of Proliferation and Promotion of Apoptosis and Autophagy

Recent studies have reported the crucial role of stanniocalcin-2 (STC2) in hepatocellular carcinoma; however, its role in head and neck squamous cell carcinoma (HNSCC) remains elusive. In this study, microRNA-206 (miR-206) was predicted to target STC2 gene. The study herein aimed to elucidate the effect of miR-206 on HNSCC by targeting STC2. STC2 was highly expressed in HNSCC tissues and cells. By targeting STC2, miR-206 decreased mRNA and protein expression of STC2. Importantly, our study showed that miR-206 blocked the Akt signaling pathway by inhibiting STC2. Intriguingly, our data from in vitro and in vivo experiments suggested that miR-206 overexpression led to decreased cell proliferation and increased cell apoptosis and autophagy, as well as suppressed tumor growth; whereas, STC2 silencing reversed the effects of miR-206 inhibitor on those biological behaviors. In this study, we investigated the antioncogenic effect of miR-206 on HNSCC by targeting STC2, and highlighted miR-206/STC2 aixs as potential therapeutic targets for HNSCC.

Genetic Variants in miRNAs Are Associated With Risk of Non-syndromic Tooth Agenesis

Non-syndromic tooth agenesis (NSTA) is one of the most common dental abnormalities. MiRNAs participated in the craniofacial and tooth development. Therefore, single nucleotide polymorphisms (SNPs) in miRNA genes may contribute to the susceptibility of non-syndromic tooth agenesis. Here, a total of 625 non-syndromic tooth agenesis cases and 1,144 healthy controls were recruited, and four miRNA SNPs (miR-146a/rs2910164, miR-196a2/rs11614913, pre-miR-605/rs2043556, pre-miR-618/rs2682818) were genotyped by the TaqMan platform. Rs2043556 showed nominal associations with risk of non-syndromic tooth agenesis (P _Add = 0.021) in the overall analysis, as well as upper lateral incisor agenesis (P _Add = 0.047) and lower incisor agenesis (P _Add = 0.049) in the subgroup analysis. Notably, its significant association with upper canine agenesis was observed (P _Add = 0.0016). Rs2043556 affected the mature of miR-605-3p and miR-605-5p while dual-luciferase report analysis indicated that MDM2 was the binding target of miR-605-5p. Our study indicated that pre-miR-605 rs2043556 was associated with risk of non-syndromic tooth agenesis.

Identification of core biomarkers associated with pathogenesis and prognostic outcomes of laryngeal squamous-cell cancer using bioinformatics analysis

PURPOSE

Despite advances in the treatment of laryngeal squamous-cell carcinoma (LSCC), the survival rate of LSCC remains poor. Thereby, it is urgent to identify novel diagnostic and prognostic biomarkers for LSCC. The study aimed to identify potential core genes associated with the pathogenesis and prognosis of LSCC.

METHODS

Differentially expressed genes between LSCC and normal laryngeal tissue samples were screened by an integrated analysis of data from GEO and TCGA databases. Core genes related to the pathogenesis and prognosis of LSCC were identified by employing protein-protein interaction network and Cox proportional hazards model analyses.

RESULTS

Ten hub genes (AURKA, AURKB, CDC45, KIF2C, NDC80, EXO1, TYMS, RAD51AP1, ITGA3, and UBE2T) that might be highly related to the pathogenesis of LSCC were identified. An eight-gene prognostic signature consisted of ZG16B, STATH, RTN4R, MSRA, CBX8, SLC5A1, EFNB1 and CNTFR was constructed with a good performance in predicting overall survivals.

CONCLUSION

Our findings might shed some new light on the pathogenesis of LSCC and help identify new therapeutic targets of LSCC.

Transcriptomics and Epigenomics in head and neck cancer: available repositories and molecular signatures

For many years, head and neck squamous cell carcinoma (HNSCC) has been considered as a single entity. However, in the last decades HNSCC complexity and heterogeneity have been recognized. In parallel, high-throughput omics techniques had allowed picturing a larger spectrum of the behavior and characteristics of molecules in cancer and a large set of omics web-based tools and informative repository databases have been developed. The objective of the present review is to provide an overview on biological, prognostic and predictive molecular signatures in HNSCC. To contextualize the selected data, our literature survey includes a short summary of the main characteristics of omics data repositories and web-tools for data analyses. The timeframe of our analysis was fixed, encompassing papers published between January 2015 and January 2019. From more than 1000 papers evaluated, 61 omics studies were selected: 33 investigating mRNA signatures, 11 and 13 related to miRNA and other non-coding-RNA signatures and 4 analyzing DNA methylation signatures. More than half of identified signatures (36) had a prognostic value but only in 10 studies selection of a specific anatomical sub-site (8 oral cavity, 1 oropharynx and 1 both oral cavity and oropharynx) was performed. Noteworthy, although the sample size included in many studies was limited, about one-half of the retrieved studies reported an external validation on independent dataset(s), strengthening the relevance of the obtained data. Finally, we highlighted the development and exploitation of three gene-expression signatures, whose clinical impact on prognosis/prediction of treatment response could be high. Based on this overview on omics-related literature in HNSCC, we identified some limits and strengths. The major limits are represented by the low number of signatures associated to DNA methylation and to non-coding RNA (miRNA, lncRNA and piRNAs) and the availability of a single dataset with multiple omics on more than 500 HNSCC (i.e. TCGA). The major strengths rely on the integration of multiple datasets through meta-analysis approaches and on the growing integration among omics data obtained on the same cohort of patients. Moreover, new approaches based on artificial intelligence and informatic analyses are expected to be available in the next future.

A Novel Biomarker Based on miRNA to Predict the Prognosis of Muscle-Invasive Bladder Urothelial Carcinoma

Muscle-invasive bladder urothelial carcinoma (MIBC) is characteristic of high mortality and high recurrence. Distinguishing the prognostic risk of MIBC at the molecular level of miRNA expression is rarely performed and thus of great significance for the management and treatment of MIBC in clinics. Adaptive lasso Cox's proportional hazards model was used to explore the relationship between differential expression miRNAs (DEmiRNAs) and MIBC survival. Furthermore, we evaluated the epithelial-mesenchymal transition (EMT) score and immune infiltration abundance by exploring EMT signature genes and TIMER database, respectively. A total of 8 DEmiRNAs were detected to be associated with the survival rate of MIBC by using the lasso Cox algorithm. Through the linear combination of these 8 DEmiRNAs, we constructed a calculated marker, which could be used to distinguish the prognosis risk in both TCGA dataset (HR = 2.03, 95% CI = (1.47, 2.83)) and independent validation dataset (HR = 7.74, 95% CI = (1.05, 56.93)). Meanwhile, the constructed marker had reasonably high predictive values of the AUC (area under the curve) in the TCGA dataset and validation dataset being 0.73 and 0.63, respectively. In addition, we observed that the expression values of let-7c, miR-100, and miR-145 were associated with EMT score and the abundance of macrophage in tumor tissue as well. This newly identified risk score signature based on the combination of 8 miRNAs could significantly predict the prognostic risk of MIBC and might provide insight into immunotherapy and targeted therapy of MIBC.

Combined identification of three miRNAs in serum as effective diagnostic biomarkers for HNSCC

Background: Head and neck squamous cell carcinoma (HNSCC) is a disastrous disease with substantial morbidity and mortality. This study aims to explore the effective diagnostic and prognostic biomarkers for HNSCC.

Methods: MiRNA expression data and corresponding clinical information of HNSCC from The Cancer Genome Atlas (TCGA) database were analyzed comprehensively to identify the miRNAs with diagnostic and prognostic power. The predictive ability of different classifications was analyzed for the three-miRNA combinations. Diagnostic and prognostic value were then evaluated and verified in clinical patients.

Findings: 128 differentially expressed miRNAs in HNSCC tissues were identified in the TCGA dataset, and 10 miRNAs were finally selected for further study. Classification analysis developed a three-miRNA signature of hsa-mir-383, hsa-mir-615, and hsa-mir-877 with the best diagnosis power, which was verified in validation patients. Survival analysis indicated that different expression levels of hsa-mir-383, rather than that of hsa-mir-615 or hsa-mir-877 led to significantly different survival rates in both cohorts. Furthermore, the multivariate Cox hazards analysis suggested that the microRNA signature yielded statistical significance to predict clinical outcome independently from other clinical variables in validation patients.

Interpretation: A three-miRNA signature of hsa-mir-383, hsa-mir-615, and hsa-mir-877 may serve as an excellent diagnostic biomarker for HNSCC, and potential prognostic significance for HNSCC patients.

Funding: This work was supported by the grants of the National Natural Science Foundation of China (81901021), Key Research and Development Program of Shandong (2019GSF108277), China postdoctoral Scinence Foundation Grant (2019M652380), Fundamental Research Funds of Shandong University (2018CJ047).

MicroRNA expression patterns in oral squamous cell carcinoma: hsa-mir-99b-3p and hsa-mir-100-5p as novel prognostic markers for oral cancer

BACKGROUND

MicroRNAs (miRNA) recently evolved as potential cancer biomarkers. Therefore, the aim of the present study was to evaluate the prognostic impact of eight miRNAs connected to oral squamous cell carcinoma (OSCC).

METHOD

Expression levels of hsa-mir-21-5p, hsa-mir-29b-3p, hsa-mir-31-5p, hsa-mir-99a-5p, hsa-mir-99b-3p, hsa-mir-100-5p, hsa-mir-143-3p and hsa-mir-155-5p were analyzed in tumor tissue (n = 36) and healthy oral mucosal tissue (n = 17) and correlated with clinical variables. Results of the study cohort were validated in an OSCC cohort of The Cancer Genome Atlas.

RESULTS

Increased hsa-mir-99b-3p expression level showed a tendency toward advanced tumor stages, and high levels of hsa-mir-100-5p expression were associated with extracapsular extension. While a high expression level of hsa-mir-99b-3p was associated with better survival, a high expression level of hsa-mir-100-5p was correlated with a poorer survival in the study cohort.

CONCLUSION

Our results indicate that hsa-mir-99b-3p and hsa-mir-100-5p may serve as novel prognostic biomarkers in OSCC.

miR-618 Suppresses Metastasis in Gastric Cancer by Downregulating the Expression of TGF-β2

Recent studies have demonstrated that microRNAs regulate gene expression and are related to cancer progression. Increasing evidence shows that miR-618 plays an important role in a variety of tumors, including thyroid carcinomas, breast cancer and lymphoma cancer. However, no studies have examined the expression or function of miR-618 in gastric cancer (GC). In this study, we examined the effects and molecular mechanisms of miR-618 in GC. We compared the expression levels of miR-618 in 90 paired GC tissues and adjacent noncancerous tissues. Cell cycle, apoptosis and transwell assays were performed in GC cells with miR-618 mimic or inhibitor in vitro. We first used quantitative PCR(qPCR) to show that miR-618 expression levels were downregulated in GC tissues, which showed statistical significance. Next we used transwell assays to prove that miR-618 suppressed the invasion and migration capacity of GC cells. Furthermore, screening of the miRDB and Target Scan Human databases indicated TGF-β2 as a downstream target of miR-618. In further research, we identified TGF-β2 as a target gene of miR-618 by the luciferase reporter assay. Western blot analysis confirmed that TGF-β2 expression was inversely correlated with miR-618 expression. In situ hybridization showed that miR-618 expression level was downregulated in GC tissues. In conclusion, our findings suggest that miR-618 may function as a tumor suppressor in GC and suppresses metastasis in GC by negatively regulating the transcriptional level of TGF-β2. Anat Rec, 302:931-940, 2019. © 2019 Wiley Periodicals, Inc.

Expression level and prospective mechanism of miRNA-99a-3p in head and neck squamous cell carcinoma based on miRNA-chip and miRNA-sequencing data in 1, 167 cases

BACKGROUND

The role of miR-99a-3p in Head and neck squamous cell carcinoma (HNSCC) has not been reported. Therefore, in this study, we examined the expression level and its molecular mechanisms of miR-99a-3p in HNSCC.

MATERIALS AND METHODS

MiR-99a-3p-related miRNA-chip and miRNA-sequencing data were collected. We then carried out meta-analyses to pool the standard mean difference (SMD) value and generate a summarized receiver operating characteristic (sROC) curve. MiR-99a-3p mimic was transfected into FaDu cells and those genes influenced by miR-99a-3p were gathered. The target genes were also predicted from 12 tools through miRwalk2.0, and combined with differentially expressed genes in HNSCC from the The Cancer Genome Atlas and Genotype-Tissue Expression sequencing databases. FunRich and DAVID were used for the pathway signaling analyses for the potential targets of miR-99a-3p in HNSCC.

RESULTS

The SMD was -0.30 (95% CI: -0.51, -0.08) in the fixed-effect model and -0.28 (95% CI: -0.67, 0.10) in the random-effect model (I2 = 60%), indicating a reduced expression level of miR-99a-3p in HNSCC tissues based on 1167 cases. In the sROC curve, the area under the curve (AUC) was 0.77 (95% CI: 0.73, 0.81). The 251 potential targets of miR-99a-3p were enriched in several pathways related to cancer, with the "Pathways in cancer" standing at the top. vascular endothelial growth factor A was selected as an example with up-regulated trend in HNSCC tissues.

CONCLUSION

MiR-99a-3p exhibits a significant lower expression status in HNSCC, and this reduced or deletion status promotes the malignant progression of HNSCC. However, its molecular mechanism is still unclear and requires further investigation.

MicroRNA-9 inhibits growth and invasion of head and neck cancer cells and is a predictive biomarker of response to plerixafor, an inhibitor of its target CXCR4

Head and neck squamous cell carcinomas (HNSCC) are associated with poor morbidity and mortality. Current treatment strategies are highly toxic and do not benefit over 50% of patients. There is therefore a crucial need for predictive and/or prognostic biomarkers to allow treatment stratification for individual patients. One class of biomarkers that has recently gained importance are microRNA (miRNA). MiRNA are small, noncoding molecules which regulate gene expression post‐transcriptionally. We performed miRNA expression profiling of a cohort of head and neck tumours with known clinical outcomes. The results showed miR‐9 to be significantly downregulated in patients with poor treatment outcome, indicating its role as a potential biomarker in HNSCC. Overexpression of miR‐9 in HNSCC cell lines significantly decreased cellular proliferation and inhibited colony formation in soft agar. Conversely, miR‐9 knockdown significantly increased both these features. Importantly, endogenous CXCR4 expression levels, a known target of miR‐9, inversely correlated with miR‐9 expression in a panel of HNSCC cell lines tested. Induced overexpression of CXCR4 in low expressing cells increased proliferation, colony formation and cell cycle progression. Moreover, CXCR4‐specific ligand, CXCL12, enhanced cellular proliferation, migration, colony formation and invasion in CXCR4‐overexpressing and similarly in miR‐9 knockdown cells. CXCR4‐specific inhibitor plerixafor abrogated the oncogenic phenotype of CXCR4 overexpression as well as miR‐9 knockdown. Our data demonstrate a clear role for miR‐9 as a tumour suppressor microRNA in HNSCC, and its role seems to be mediated through CXCR4 suppression. MiR‐9 knockdown, similar to CXCR4 overexpression, significantly promoted aggressive HNSCC tumour cell characteristics. Our results suggest CXCR4‐specific inhibitor plerixafor as a potential therapeutic agent, and miR‐9 as a possible predictive biomarker of treatment response in HNSCC.

A miRNA signature suggestive of nodal metastases from laryngeal carcinoma

The discovery that miRNAs are frequently deregulated in tumours offers the opportunity to identify them as prognostic and diagnostic markers. The aim of this multicentric study is to identify a miRNA expression profile specific for laryngeal cancer. The secondary endpoint was to identify specific deregulated miRNAs with potential as prognostic biomarkers for tumour spread and nodal involvement, and specifically to search for a miRNA pattern pathognomonic for N+ laryngeal cancer and for N- tissues. We identified 20 miRNAs specific for laryngeal cancer and a tissue-specific miRNA signature that is predictive of lymph node metastases in laryngeal carcinoma characterised by 11 miRNAs, seven of which are overexpressed (upregulated) and four downregulated. These results allow the identification of a group of potential specific tumour biomarkers for laryngeal carcinoma that can be used to improve its diagnosis, particularly in early stages, as well as its prognosis.

MicroRNA-155, -185 and -193b as biomarkers in human papillomavirus positive and negative tonsillar and base of tongue squamous cell carcinoma

OBJECTIVE

Three-year disease-free survival (DFS) is 80% for human papillomavirus (HPV) positive tonsillar and base of tongue cancer (TSCC/BOTSCC) treated with radiotherapy alone, and today's intensified therapy does not improve prognosis. More markers are therefore needed to more accurately identify patients with good prognosis or in need of alternative therapy. Here, microRNAs (miRs) 155, 185 and 193b were examined as potential prognostic markers in TSCC/BOTSCC.

MATERIAL AND METHODS

168 TSCC/BOTSCC patients diagnosed 2000-2013, with known data on HPV-status, CD8⁺ tumour infiltrating lymphocytes, tumour staging and survival were examined for expression of miR-155, -185 and -193b using Real-Time PCR. Associations between miR expression and patient and tumour characteristics were analysed using univariate testing and multivariate regression.

RESULTS

Tumours compared to normal tonsils showed decreased miR-155 and increased miR-193b expression. miR-155 expression was associated with HPV-positivity, low T-stage, high CD8⁺ TIL counts and improved survival. miR-185 expression was associated with HPV-negativity and a tendency towards decreased survival, while miR-193b expression was associated with higher T-stage, male gender and lower CD8⁺ TIL counts, but not with outcome. Upon Cox regression, miR-185 was the only miR significantly associated with survival. Combining miR-155 and miR-185 to predict outcome in HPV⁺ patients yielded an area under curve (AUC) of 71%.

CONCLUSION

Increased miR-155 expression was found as a positive predictor of survival, with the effect mainly due to its association with high CD8⁺ TIL numbers, while miR-185 independently associated with decreased survival. Addition of these miRs to previously validated prognostic biomarkers could improve patient stratification accuracy.

Telomeric Repeat-Containing RNAs (TERRA) Decrease in Squamous Cell Carcinoma of the Head and Neck Is Associated with Worsened Clinical Outcome

Telomeres are transcribed into noncoding telomeric repeat-containing RNAs (TERRA), which are essential for telomere maintenance. Deregulation of TERRA transcription impairs telomere metabolism and a role in tumorigenesis has been proposed. Head and neck cancer (HNC) is one of the most frequent cancers worldwide, with head and neck squamous cell carcinoma (HNSCC) being the predominant type. Since HNSCC patients are characterized by altered telomere maintenance, a dysfunction in telomere transcription can be hypothesized. In this prospective study, we compared TERRA levels in the tumor and matched normal tissue from 23 HNSCC patients. We then classified patients in two categories according to the level of TERRA expression in the tumor compared to the normal tissue: (1) lower expression in the tumor, (2) higher or similar expression in tumor. A significant proportion of patients in the first group died of the disease within less than 34 months postsurgery, while the majority of patients in the second group were alive and disease-free. Our results highlight a striking correlation between TERRA expression and tumor aggressiveness in HNSCC suggesting that TERRA levels may be proposed as a novel molecular prognostic marker for HNSCC.

Role of non-coding RNAs in head and neck squamous cell carcinoma: A narrative review

Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer worldwide with high recurrence, metastasis, and poor treatment outcome. Recent studies have reported that non-coding RNA (ncRNA) might play critical role in regulating different types of cancer. MicroRNAs (miRs) are short ncRNAs (20-25 nucleotides) responsible for post-transcriptional regulation of gene expression and may have a role in oncogenesis by acting as oncomiRs or tumor suppressor miRs. Long non-coding RNAs (lncRNAs) are heterogenous group of ncRNAs more than 200 nucleotides long, can act in cis and/or in trans, and have been also implicated in carcinogenesis. These molecules have been suggested to be promising candidates as diagnostic and prognostic biomarkers and for development of novel therapeutic approaches. In this review, we have summarized recent findings on role of these ncRNAs in HPV-negative (HPV-ve) and HPV-positive (HPV+ve) HNSCC. The available literature supports differential expression of both microRNAs and long non-coding RNAs, which include oncogenic ncRNAs (miR-21, miR-31, miR-155, miR-211, HOTAIR, and MALAT1) and tumor suppressor ncRNAs (let7d, miR-17, miR-375, miR-139, and MEG3) in HPV+ve HNSCC tumors as compared to HPV-ve tumors and they have distinct role in the pathophysiology of these two types of HNSCCs.

Comparative Analysis of MicroRNA Expression among Benign and Malignant Tongue Tissue and Plasma of Patients with Tongue Cancer

Background

Identification of a microRNA (miRNA) pattern to be used as a biomarker for HNSCC is challenging given the heterogeneity of the disease and different methodologies used. To better define the field, we performed a prospective analysis of blood, tumor, and paired benign tissues in tongue squamous cell carcinoma (SCC) patients.

Methods

Plasma samples were collected prior to surgery, and paired tumor and benign tissue blocks were collected from tongue cancer resections. Circulating free and exosomal miRNA, and paired tumor and benign tissues miRNA were analyzed. TaqMan-based miRNA arrays were used to quantitate the expression of 747 human miRNAs. The comparative Ct method assessed the miRNA profile results, and Student’s t-test determined statistical significance between tumor and benign samples.

Results

Sixteen of 359 miRNAs detected were differentially expressed between paired tumor and benign tissue. Nine were upregulated, and seven downregulated in tumor tissue. All nine upregulated and six of seven downregulated tumor miRNAs were expressed in circulating exosomes. In contrast, eight of nine upregulated and four of seven downregulated tumor miRNAs were circulating free in the plasma.

Conclusion

An aberrantly expressed pattern of miRNA was identified in both tumor and plasma of patients with tongue SCC, suggesting this may be a biomarker for SCC of the oral tongue. Circulating exosomes appear to be a more reliable method for evaluation of circulating tumor-miRNA expression. Further studies with a larger cohort of patients and serial blood samples are needed to validate our findings.

miR-618 Inhibits Prostate Cancer Migration and Invasion by Targeting FOXP2

miRNAs play critical role in the development and progression of prostate cancer. Here we studied the role of miR-618 in prostate cancer migration and invasion. miR-618 was downregulated in metastatic androgen-independent prostate cancer (AIPC), patients with low miR-618 had poor outcome. Overexpression of miR-618 inhibited migration and invasion and induced mesenchymal to epithelial transition (MET). Conversely, knockdown of miR-618 promoted migration and invasion and induced epithelial to mesenchymal transition (EMT). FOXP2 was the direct target of miR-618, and promoted TGF-β expression, inhibition of TGF-β reversed the effect of miR-618 knockdown. We further analyzed the correlation between miR-618 expression and FOXP2 in human prostate cancer tissues, and found there was a negative correlation between miR-618 expression and FOXP2 levels. In conclusion, we found miR-618 inhibited prostate cancer migration and invasion by targeting FOXP2 and inhibiting TGF-β.