Identification of endometrioid endometrial carcinoma-associated microRNAs in tissue and plasma

The overexpression of miR-30a affects cell proliferation of chondrosarcoma via targeting Runx2

MicroRNAs (miRNAs) are emerging as important epigenetic modulators of multiple target genes, leading to abnormal cellular signaling involving cellular proliferation in cancers. Aberrant miRNA expression has been observed in human chondrosarcoma (CS). The purpose of the present study was to evaluate the expression and molecular mechanisms of Runx2 and miR-30a in human CS tissues and CS cell lines JJ012, SW1353, and L3252. In the present study, we found that the expression of miR-30a was markedly downregulated in CS cell lines and human CS tissues, compared to matched non-tumor-associated tissues. Furthermore, miR-30a expression was inversely proportional to that of Runx2 messenger RNA (mRNA) and protein. Upregulation of miR-30a dramatically reduced the proliferation, colony formation, and cell cycle-related proteins of CS cells. Flow cytometry analysis showed that ectopic expression of miR-30a significantly decreased the percentage of S phase cells and increased the percentage of G1/G0 phase cells. Luciferase reporter assays confirmed that miR-30a binding to the 3'-untranslated region (3'-UTR) region of Runx2 inhibited the expression of Runx2 in cancer cells. Taken together, our results suggest that miR-30a plays an important role to inhibit the proliferation of CS cells and presents a novel mechanism for direct miRNA-mediated suppression of Runx2 in CS. Thus, miR-30a/Runx2 may have an important role in treatment of CS patients.

Small RNA Sequencing Uncovers New miRNAs and moRNAs Differentially Expressed in Normal and Primary Myelofibrosis CD34+ Cells

Myeloproliferative neoplasms (MPN) are chronic myeloid cancers thought to arise at the level of CD34+ hematopoietic stem/progenitor cells. They include essential thrombocythemia (ET), polycythemia vera (PV) and primary myelofibrosis (PMF). All can progress to acute leukemia, but PMF carries the worst prognosis. Increasing evidences indicate that deregulation of microRNAs (miRNAs) might plays an important role in hematologic malignancies, including MPN. To attain deeper knowledge of short RNAs (sRNAs) expression pattern in CD34+ cells and of their possible role in mediating post-transcriptional regulation in PMF, we sequenced with Illumina HiSeq2000 technology CD34+ cells from healthy subjects and PMF patients. We detected the expression of 784 known miRNAs, with a prevalence of miRNA up-regulation in PMF samples, and discovered 34 new miRNAs and 99 new miRNA-offset RNAs (moRNAs), in CD34+ cells. Thirty-seven small RNAs were differentially expressed in PMF patients compared with healthy subjects, according to microRNA sequencing data. Five miRNAs (miR-10b-5p, miR-19b-3p, miR-29a-3p, miR-379-5p, and miR-543) were deregulated also in PMF granulocytes. Moreover, 3’-moR-128-2 resulted consistently downregulated in PMF according to RNA-seq and qRT-PCR data both in CD34+ cells and granulocytes. Target predictions of these validated small RNAs de-regulated in PMF and functional enrichment analyses highlighted many interesting pathways involved in tumor development and progression, such as signaling by FGFR and DAP12 and Oncogene Induced Senescence. As a whole, data obtained in this study deepened the knowledge of miRNAs and moRNAs altered expression in PMF CD34+ cells and allowed to identify and validate a specific small RNA profile that distinguishes PMF granulocytes from those of normal subjects. We thus provided new information regarding the possible role of miRNAs and, specifically, of new moRNAs in this disease.

Downregulation of MiR-30a is Associated with Poor Prognosis in Lung Cancer

BACKGROUND

Recent reports have suggested that miR-30a plays a tumor-suppressive role in various cancers. However, miR-30a has not been completely studied in non-small lung cancer (NSCLC). Thus, the aim of the present study was to clarify the association between the expression of miR-30a and the clinicopathological features in NSCLC patients.

MATERIAL AND METHODS

Total RNA of miR-30a was extracted from 125 pairs of NSCLC patients (male 75, female 50) and their matching normal tissues. The miR-30a level was detected by using quantitative real-time polymerase chain reaction (qRT-PCR). Simultaneously, the 2-ΔCq method was used to calculate the correlation between miR-30a expression and the clinicopathological parameters and prognosis of NSCLC patients.

RESULTS

MiR-30a expression was significantly down-regulated in NSCLC tissues (4.0696±2.4178) compared to their non-tumor lung tissues (7.4530±3.0561, P<0.001). Level of miR-30a was negatively correlated to tumor size (r=-0.197, P=0.028), lymphatic metastasis (r=-0.312, P<0.001), clinical TNM stage (r=-0.299, P=0.001), pathological grading (I/II vs. III, r=-0.224, P=0.001), and histological classification (r=-0.299, P=0.001). Survival time was 3.23±2.18 months in the low miR-30a expression group, remarkably shorter than that of the high expression group (20.72±11.63 months, P<0.001).

CONCLUSIONS

MiR-30a may be regarded as a tumor suppressor in NSCLC, and it could become a prognostic marker and potential therapeutic target for NSCLC.

Circulating small non-coding RNA signature in head and neck squamous cell carcinoma

The Head and Neck Squamous Cell Carcinoma (HNSCC) is the sixth most common human cancer, causing 350,000 individuals die worldwide each year. The overall prognosis in HNSCC patients has not significantly changed for the last decade. Complete understanding of the molecular mechanisms in HNSCC carcinogenesis could allow an earlier diagnosis and the use of more specific and effective therapies. In the present study we used deep sequencing to characterize small non-coding RNAs (sncRNAs) in serum from HNSCC patients and healthy donors. We identified, for the first time, a multi-marker signature of 3 major classes of circulating sncRNAs in HNSCC, revealing the presence of circulating novel and known miRNAs, and tRNA- and YRNA-derived small RNAs that were significantly deregulated in the sera of HNSCC patients compared to healthy controls. By implementing a triple-filtering approach we identified a subset of highly biologically relevant miRNA-mRNA interactions and we demonstrated that the same genes/pathways affected by somatic mutations in cancer are affected by changes in the abundance of miRNAs. Therefore, one important conclusion from our work is that during cancer development, there seems to be a convergence of oncogenic processes driven by somatic mutations and/or miRNA regulation affecting key cellular pathways.

Expression Levels of miR-30a-5p in Papillary Thyroid Carcinoma: A Comparison Between Serum and Fine Needle Aspiration Biopsy Samples

BACKGROUND

Fine needle aspiration biopsy (FNAB) is a useful tool in the diagnosis of thyroid nodules. However, some limitations exist as approximately 25% of the cases cannot be distinguished with this method. Therefore, identification of novel diagnostic markers is very important in improving the papillary thyroid carcinoma (PTC) diagnosis. microRNAs (miRNAs) are small regulatory RNA molecules that have been involved in a variety of biological processes, including tumorigenesis. Moreover, determination of miRNAs with prognostic, diagnostic, and therapeutic potential is of a great interest today.

AIMS

In the present study, we evaluated the expression level of miR-30a-5p in serum and FNAB samples of PTC patients.

METHODS

A total of 60 cases were included in the study, with the patients subdivided into four groups; benign, atypical cells of undetermined significance (ACUS), malignant group, including Hurthle cell PTC (HC-PTC), and malignant without Hurthle cell PTC (non-HC-PTC). Peripheral blood and FNAB samples of the cases were collected. The serum and FNAB expression levels of miR-30a-5p among the groups were compared. The miR-30a-5p expression level was determined using real-time polymerase chain reaction (RT-PCR).

RESULTS

According to both pre- and postoperative pathological diagnosis, miR-30a-5p levels were significantly increased in both serum and FNAB samples of HC-PTC and non-HC-PTC groups compared to other groups. This increase was more evident in the non-HC-PTC group (p=0.0245 for FNAB, p=0.0166 for serum).

CONCLUSIONS

The results of this study suggest that miR-30a-5p might be a novel diagnostic marker candidate in PTC. Further studies are required to investigate this possibility.

Assay reproducibility in clinical studies of plasma miRNA

There are increasing reports of plasma miRNAs as biomarkers of human disease but few standards in methodologic reporting, leading to inconsistent data. We systematically reviewed plasma miRNA studies published between July 2013-June 2014 to assess methodology. Six parameters were investigated: time to plasma extraction, methods of RNA extraction, type of miRNA, quantification, cycle threshold (Ct) setting, and methods of statistical analysis. We compared these data with a proposed standard methodologic technique. Beginning with initial screening for 380 miRNAs using microfluidic array technology and validation in an additional cohort of patients, we compared 11 miRNAs that exhibited differential expression between 16 patients with benign colorectal neoplasms (advanced adenomas) and 16 patients without any neoplasm (controls). Plasma was isolated immediately, 12, 24, 48, or 72 h following phlebotomy. miRNA was extracted using two different techniques (Trizol LS with pre-amplification or modified miRNeasy). We performed Taqman-based RT-PCR assays for the 11 miRNAs with subsequent analyses using a variable Ct setting or a fixed Ct set at 0.01, 0.03, 0.05, or 0.5. Assays were performed in duplicate by two different operators. RNU6 was the internal reference. Systematic review yielded 74 manuscripts meeting inclusion criteria. One manuscript (1.4%) documented all 6 methodological parameters, while < 5% of studies listed Ct setting. In our proposed standard technique, plasma extraction ≤12 h provided consistent ΔCt. miRNeasy extraction yielded higher miRNA concentrations and fewer non-expressed miRNAs compared to Trizol LS (1/704 miRNAs [0.14%] vs 109/704 miRNAs [15%], not expressed, respectively). A fixed Ct bar setting of 0.03 yielded the most reproducible data, provided that <10% miRNA were non-expressed. There was no significant intra-operator variability. There was significant inter-operator variation using Trizol LS extraction, while this was negligible using modified miRNeasy. For standardized reporting, we recommend plasma extraction ≤ 12 h, using modified miRNeasy extraction and utilizing a 0.03 Ct.

miREC: a database of miRNAs involved in the development of endometrial cancer

BACKGROUND

Endometrial cancer (EC) is the most frequently diagnosed gynecological malignancy and the fourth most common cancer diagnosis overall among women. As with many other forms of cancer, it has been shown that certain miRNAs are differentially expressed in EC and these miRNAs are believed to play important roles as regulators of processes involved in the development of the disease. With the rapidly growing number of studies of miRNA expression in EC, there is a need to organize the data, combine the findings from experimental studies of EC with information from various miRNA databases, and make the integrated information easily accessible for the EC research community.

FINDINGS

The miREC database is an organized collection of data and information about miRNAs shown to be differentially expressed in EC. The database can be used to map connections between miRNAs and their target genes in order to identify specific miRNAs that are potentially important for the development of EC. The aim of the miREC database is to integrate all available information about miRNAs and target genes involved in the development of endometrial cancer, and to provide a comprehensive, up-to-date, and easily accessible source of knowledge regarding the role of miRNAs in the development of EC. Database URL: http://www.mirecdb.org .

CONCLUSIONS

Several databases have been published that store information about all miRNA targets that have been predicted or experimentally verified to date. It would be a time-consuming task to navigate between these different data sources and literature to gather information about a specific disease, such as endometrial cancer. The miREC database is a specialized data repository that, in addition to miRNA target information, keeps track of the differential expression of genes and miRNAs potentially involved in endometrial cancer development. By providing flexible search functions it becomes easy to search for EC-associated genes and miRNAs from different starting points, such as differential expression and genomic loci (based on genomic aberrations).

MicroRNAS in endometrial cancer: recent advances and potential clinical applications

Endometrial cancer is a common malignant gynecological tumor, but there are few biomarkers that are useful for early and accurate diagnosis and few treatments other than surgery. However, use of microRNAs (miRNAs) that induces gene downregulation in cells may permit effective and minimally invasive diagnosis and treatment. In endometrial cancer cells, expression levels of miRNAs including miR-185, miR-210 and miR-423 are upregulated and those of miR-let7e, miR-30c and miR-221 are downregulated compared to normal tissues, and these miRNAs are involved in carcinogenesis, invasion and metastasis. miRNAs with expression changes such as miR-181b, miR-324-3p and miR-518b may be used as prognostic biomarkers and transfection of miR-152 may inhibit cancer growth. However, most current studies of miRNAs are at a basic level and further work is needed to establish clinical applications targeting miRNAs.

The association between abnormal microRNA-10b expression and cancer risk: a meta-analysis

Several studies have investigated the association between abnormal microRNA-10b expression and the risk of various developing cancers, but the results are inconsistent. We searched all publications addressing the level of microRNA-10b expression in cancer cases and noncancerous controls (Accessed: August 2014). Thirty-six studies on 14 types of cancer were included. Among them, 25 studies were subjected to the meta-analysis with a vote-counting strategy, 13 studies were estimated using odds ratio (OR) and diagnostic accuracy, and 2 studies were assessed by both methods. It was found that vestibular schwannomas ranked first among the reported cancer types with up-regulated microRNA-10b expression; melanoma ranked first among the reported cancer types with down-regulated microRNA-10b expression; while breast cancer and hepatocellular cancer presented inconsistent microRNA-10b regulation. Of 13 included studies calculated for OR and diagnostic accuracy, it was shown that high-expression of microRNA-10b could be significantly associated with cancer risk (OR = 32.80, 95% CI: 11.90–90.37, P<0.0001), and the area under the summary receiver operating characteristic (SROC) curve for microRNA-10b high-expression in the diagnosis of cancer is 0.81, which suggested that high-expression of microRNA-10b can predict worse outcomes in some types of cancer and the regular monitoring of miR-10b expression might be useful in the clinical practice.

The clinical utility of microRNA-21 as novel biomarker for diagnosing human cancers

With cancer being a major cause of death worldwide, microRNAs (miRNAs) have been investigated as novel and non-invasive biomarkers for cancer diagnosis. Recently, microRNA-21 (miR-21) attracts much attention for its aberrant expression and has been widely studied in various cancers. However, the inconsistent results from studies make it hard to evaluate the diagnostic value of miR-21 in cancer diagnosis, which lead us to conduct this meta-analysis. We conducted a comprehensive literature search in the Medline, Embase, PubMed, CNKI, and Web of Science before July 1, 2014. STATA 12.0 software was used for calculation and statistical analysis. The pooled sensitivity, specificity, positive and negative likelihood ratio (PLR, NLR), and diagnostic odds ratio (DOR) were used to assess the diagnostic performance of miR-21 for cancers. Seventy-three studies in 60 articles were involved in this meta-analysis, with a total of 4684 patients with cancer and 3108 controls. The overall parameters were calculated from all the included studies: sensitivity of 0.78 (95% confidence interval (CI) 0.74-0.81), specificity of 0.83 (95% CI 0.80-0.86), PLR of 4.5 (95% CI 3.8-5.4), NLR of 0.27 (95% CI 0.23-0.32); DOR of 17 (95% CI 12-23), and area under the curve (AUC) of 0.88 (95% CI 0.84-0.90). In addition, we performed subgroup analyses based on ethnicity, cancer types, and sample types. Results from subgroup analysis showed that cancer types and sample types were the sources of heterogeneity in our meta-analysis. The overall diagnostic value of miR-21 is not very high for cancer diagnosis; however, it is affected significantly by the types of cancer and specimen. MiR-21 has a relatively high diagnostic value for detecting breast cancer, and miR-21 assays based on plasma, serum, and tissue achieved relatively higher accuracy.

Clinical significance of microRNA expressions in diagnosing uterine cancer and predicting lymph node metastasis

Recently, accumulating lines of evidence have demonstrated the association between microRNA (miRNAs) expression and uterine cancer, indicating that they may serve as promising novel biomarkers for uterine cancer. Therefore, we conducted this study to systematically evaluate the diagnostic accuracy of miRNAs in discriminating the uterine cancer patients from controls and further to determine their diagnostic values in lymph node metastasis (LNM) prediction. The pooled sensitivity, specificity, and other parameters, together with summary receiver operating characteristic (SROC) curve were used to assess the overall test performance. All statistical analyses were conducted using STATA 12.0 software. A total of nine articles were included in this meta-analysis. As for the accuracy of miRNAs in differentiating uterine cancer from controls, the pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), and area under curve (AUC) were 0.84, 0.83, 4.8, 0.19, 25, and 0.90, respectively. As for the diagnostic accuracy of miRNAs in differentiating patients with LNM from those without LNM, the pooled sensitivity, specificity, PLR, NLR, DOR, and AUC were 0.75, 0.78, 3.5, 0.32, 011, and 0.83, respectively. In addition, subgroup analyses based on miRNA profiles suggested that multiple-miRNA assay displayed much better accuracy than single-miRNA assay, with an excellent AUC of 0.98 (92% sensitivity and 96% specificity). The high accuracy of multiple-miRNA assay, together with the application of miRNAs in LNM prediction, suggested that miRNAs may serve as non-invasive diagnostic markers of uterine cancer and further improve the comprehensive management of patients with uterine cancer. However, further larger studies are needed to confirm our findings.

Circulating MicroRNAs in gynecological malignancies: from detection to prediction

MicroRNAs (miRNAs) have been demonstrated to play critical roles in many physiological and pathophysiological processes. The presence of altered miRNA profiles in human body fluids has been reported for a number of diseases including gynecological malignancies. In this review, we summarized the current progresses of circulating miRNAs associated with malignancies in gynecology, with an emphasizing on the circulating miRNAs as diagnostic and prognostic biomarkers in ovarian cancer, endometrial carcinoma and cervical cancer.