Vesicle-related microRNAs in plasma of nonsmall cell lung cancer patients and correlation with survival

Circulating microRNA expression is associated with genetic subtype and survival of multiple myeloma

Circulating microRNAs (miRNAs) have shown potential as non-invasive prognostic biomarkers in cancer. Here, we investigated whether miRNAs present in the plasma of multiple myeloma (MM) patients have prognostic utility. We evaluated global miRNA expression profiles in the plasma of 12 multiple myeloma patients and 8 healthy controls using TaqMan Low-Density Arrays. Six miRNAs (miR-148a, miR-181a, miR-20a, miR-221, miR-625, and miR-99b) that were significantly upregulated in MM were selected and further quantified independently by quantitative reverse transcription PCR in plasma from 28 MM patients and 12 healthy controls. Moreover, within the patient group, the expression levels of miR-99b and miR-221 were associated with chromosomal abnormalities t(4; 14) and del(13q), respectively. High levels of miR-20a and miR-148a were related to shorter relapse-free survival. In summary, we have identified aberrant expression of particular circulating miRNAs that are associated with the genetic subtype and survival of MM. These plasma miRNAs have potential as clinical biomarkers in MM.

Circulating miR-378 and miR-451 in serum are potential biomarkers for renal cell carcinoma

Background

There is no standard serum biomarker used for diagnosis or early detection of recurrence for renal cell carcinoma (RCC) patients. MicroRNAs (miRNAs) are abundant and highly stable in blood serum, and have been recently described as powerful circulating biomarkers in a wide range of solid cancers. Our aim was to identify miRNA signature that can distinguish the blood serum of RCC patients and matched healthy controls and validate identified miRNAs as potential biomarkers for RCC.

Methods

In the screening phase of the study, blood serum of 15 RCC patients and 12 matched healthy controls were analyzed by use of the TaqMan Low-Density Arrays enabling parallel identification of expression levels of 667 miRNAs through qRT-PCR-based approach. In the validation phase, identified miRNAs were further evaluated on the independent group of 90 RCC patients and 35 matched healthy controls by use of individual qRT-PCR assays and statistically evaluated.

Results

We identified 30 miRNAs differentially expressed between serum of RCC patients and healthy controls: 19 miRNAs were up-regulated and 11 miRNAs were down-regulated in RCC patients. MiR-378, miR-451 and miR-150 were further evaluated in the independent group of patients, and two of them were successfully validated: levels of miR-378 were increased (p = 0.0003, AUC = 0.71), miR-451 levels were decreased (p < 0.0001, AUC = 0.77) in serum of RCC patients. Combination of miR-378 and miR-451 enable identification of RCC serum with the sensitivity of 81%, specificity 83% and AUC = 0.86.

Conclusions

Circulating miRNAs in serum are promising biomarkers in RCC.

MicroRNAs - Important Molecules in Lung Cancer Research

MicroRNAs (miRNA) are important regulators of gene expression. They are involved in many physiological processes ensuring the cellular homeostasis of human cells. Alterations of the miRNA expression have increasingly been associated with pathophysiologic changes of cancer cells making miRNAs currently to one of the most analyzed molecules in cancer research. Here, we provide an overview of miRNAs in lung cancer. Specifically, we address biological functions of miRNAs in lung cancer cells, miRNA signatures generated from tumor tissue and from patients’ body fluids, the potential of miRNAs as diagnostic and prognostic biomarker for lung cancer, and its role as therapeutic target.

The multifaceted exosome: biogenesis, role in normal and aberrant cellular function, and frontiers for pharmacological and biomarker opportunities

Exosomes are bioactive vesicles derived from the cell's endosomal membrane system and secreted into surrounding body fluids. Exosomes contain cell and cell-state specific cargos of protein, mRNA and miRNA. Exosome formation, cargo content, and delivery to surrounding cells is of immense biological interest considering the role that exosomes are believed to play in various pathological conditions. They aid antigen presentation by immune cells and can exhibit either anti-inflammatory or pro-inflammatory properties depending on the parent antigen-presenting cell's conditioning. Viruses can hijack a host cell's exosomal machinery to evade host defense systems aiding in the trans-infection of viruses.

Tumor derived exosomes may help establish an oncogenic niche systemically via delivery of protein, mRNA, and miRNA that can aid angiogenesis, cell proliferation, and cell survival. Exosomes have also been implicated in the spread of neurodegenerative diseases.

Studies have shown that exosomes are selectively taken up by cells distal from their release. They can reprogram the recipient cells due to their active molecular cargo. Cell-lineage and state-specific exosomes imply that they may therefore harbor body fluid-based biomarkers of unparalleled accuracy, particularly for tissues that are difficult or impossible to access.

Exosome-specific membrane proteins provide markers enabling exosome identity and selection, while cell type and cell condition-specific protein, mRNA and miRNA cargo provide a rich potential source of biomarkers. This review serves to provide an overview of the current state of the science in the burgeoning field of exosome biology.

Micro-RNAs as diagnostic or prognostic markers in human epithelial malignancies

Micro-RNAs (miRs) are important regulators of mRNA and protein expression; the ability of miR expression profilings to distinguish different cancer types and classify their sub-types has been well-described. They also represent a novel biological entity with potential value as tumour biomarkers, which can improve diagnosis, prognosis, and monitoring of treatment response for human cancers. This endeavour has been greatly facilitated by the stability of miRs in formalin-fixed paraffin-embedded (FFPE) tissues, and their detection in circulation. This review will summarize some of the key dysregulated miRs described to date in human epithelial malignancies, and their potential value as molecular bio-markers in FFPE tissues and blood samples. There remain many challenges in this domain, however, with the evolution of different platforms, the complexities of normalizing miR profiling data, and the importance of evaluating sufficiently-powered training and validation cohorts. Nonetheless, well-conducted miR profiling studies should contribute important insights into the molecular aberrations driving human cancer development and progression.

Micro-RNAs as diagnostic or prognostic markers in human epithelial malignancies

Micro-RNAs (miRs) are important regulators of mRNA and protein expression; the ability of miR expression profilings to distinguish different cancer types and classify their sub-types has been well-described. They also represent a novel biological entity with potential value as tumour biomarkers, which can improve diagnosis, prognosis, and monitoring of treatment response for human cancers. This endeavour has been greatly facilitated by the stability of miRs in formalin-fixed paraffin-embedded (FFPE) tissues, and their detection in circulation. This review will summarize some of the key dysregulated miRs described to date in human epithelial malignancies, and their potential value as molecular bio-markers in FFPE tissues and blood samples. There remain many challenges in this domain, however, with the evolution of different platforms, the complexities of normalizing miR profiling data, and the importance of evaluating sufficiently-powered training and validation cohorts. Nonetheless, well-conducted miR profiling studies should contribute important insights into the molecular aberrations driving human cancer development and progression.

MicroRNA profiling in cancer

The diagnosis of cancer has undergone major changes in the last 40 years. Once based purely on morphology, diagnosis has come to incorporate immunological, cytogenetic and molecular methods. Many cancers, especially leukaemias, are now defined by molecular markers. Gene expression profiling based on mRNA has led to further refinement of the classification and diagnosis of cancer. More recently, miRNAs (microRNAs), among other small non-coding RNA molecules, have been discovered and found to be major players in cell biology. miRNAs, having both oncogenic and tumour-suppressive functions, are dysregulated in many types of cancer. miRNAs also interfere with metastasis, apoptosis and invasiveness of cancer cells. In the present review, we discuss recent advances in miRNA profiling in human cancer. We discuss both frequent and rare tumour types and give an outlook on future developments.

Diagnostic applications of cell-free and circulating tumor cell-associated miRNAs in cancer patients

Recently, miRNA-expression profiling in primary tumors has yielded promising results. However, establishing miRNA expression in the circulation probably has advantages over determination in primary tumor tissue, further augmenting the potential applications of miRNA determination in oncology. Circulating tumor cells (CTCs) have rapidly developed as important prognostic and therapy-monitoring biomarkers in metastatic breast, colorectal and prostate cancer when enumerated, and their isolation enables subsequent analysis using various molecular applications, including miRNA-expression analysis. In addition to CTC-associated miRNAs, free circulating miRNAs have been identified in whole blood, plasma and serum. Determination of miRNAs in peripheral blood, either cell-free or CTC-associated, is expected to become important in oncology, especially when linked to and interpreted together with epithelial CTCs. In this article, we will discuss miRNA-expression profiling in primary tumors, depict the potential applications of measuring miRNA in the circulation and review the literature on cell-free circulating miRNAs, as well as offering some methodological and technical considerations on the measurement of circulating miRNAs.

Prognostic, therapeutic and diagnostic potential of microRNAs in non-small cell lung cancer

Non-small cell lung carcinomas (NSCLC) account for about 80% of lung cancers and their remarkable heterogeneity manifests in histology, pathogenesis, prognosis, and response to treatments. Recent advances in molecular characterization help stratifying NSCLC patients for their potential benefit from targeting therapies. However, the fundamental mechanisms underlying the tumoral heterogeneity remain poorly understood. Expression profiling of many microRNAs (miRNAs) in various normal and disease tissues demonstrated unique spatial and temporal expression patterns and some miRNAs have been functionally characterized as oncogenes or tumor suppressor genes. Genome-wide screening identified specific miRNA expression signatures associated with clinical outcome of NSCLC patients. A group of miRNAs that has enriched expression in normal lung was found down regulated in NSCLC and may function as tumor suppressor genes. In this review we: a) summarize the current understanding of the critical role that miRNAs play in normal cell functions and in disease biology especially in lung cancer tumorigenesis, b) highlight their potential as biomarkers for lung cancer risk stratification, outcome prediction and classification of histologic subtypes, c) critically assess current knowledge on lung-enriched miRNAs and expression of their predicted target genes in NSCLC and d) evaluate their potential as circulating biomarkers and therapeutic targets in lung cancer.

Circulating microRNA is a biomarker of pediatric Crohn disease

OBJECTIVE

The gold standard for the diagnosis and evaluation of Crohn disease (CD) is endoscopy/colonoscopy, although this is invasive, costly, and associated with risks to the patient. Recently, circulating microRNAs (miRNAs) have emerged as promising noninvasive biomarkers. Here, we examined the utility of serum miRNAs as biomarkers of CD in children.

PATIENTS AND METHODS

Studies were conducted using sera samples from patients with pediatric CD, healthy controls, and a comparison group of patients with pediatric celiac disease. Serum miRNA levels were explored initially using a microfluidic quantitative reverse transcription-polymerase chain reaction array platform. Findings were subsequently validated using quantitative reverse transcription-polymerase chain reaction in larger validation sample sets. The diagnostic utility of CD-associated serum miRNA was examined using receiver operating characteristic analysis.

RESULTS

A survey of miRNA levels in the sera of control and patients with CD detected significant elevation of 24 miRNAs, 11 of which were chosen for further validation. All of the candidate biomarker miRNAs were confirmed in an independent CD sample set (n = 46). To explore the specificity of the CD-associated miRNAs, they were measured in the sera of patients with celiac disease (n = 12); none were changed compared with healthy controls. Receiver operating characteristic analyses revealed that serum miRNAs have promising diagnostic utility, with sensitivities for CD above 80%. Significant decreases in serum miRNAs were observed in 24 incident patients with pediatric CD after 6 months of treatment.

CONCLUSIONS

The present study identifies 11 CD-associated serum miRNA with encouraging diagnostic potential. Our findings suggest serum miRNAs may prove useful as noninvasive biomarkers in CD.

Circulating microRNA is a biomarker of pediatric Crohn disease

OBJECTIVE

The gold standard for the diagnosis and evaluation of Crohn disease (CD) is endoscopy/colonoscopy, although this is invasive, costly, and associated with risks to the patient. Recently, circulating microRNAs (miRNAs) have emerged as promising noninvasive biomarkers. Here, we examined the utility of serum miRNAs as biomarkers of CD in children.

PATIENTS AND METHODS

Studies were conducted using sera samples from patients with pediatric CD, healthy controls, and a comparison group of patients with pediatric celiac disease. Serum miRNA levels were explored initially using a microfluidic quantitative reverse transcription-polymerase chain reaction array platform. Findings were subsequently validated using quantitative reverse transcription-polymerase chain reaction in larger validation sample sets. The diagnostic utility of CD-associated serum miRNA was examined using receiver operating characteristic analysis.

RESULTS

A survey of miRNA levels in the sera of control and patients with CD detected significant elevation of 24 miRNAs, 11 of which were chosen for further validation. All of the candidate biomarker miRNAs were confirmed in an independent CD sample set (n = 46). To explore the specificity of the CD-associated miRNAs, they were measured in the sera of patients with celiac disease (n = 12); none were changed compared with healthy controls. Receiver operating characteristic analyses revealed that serum miRNAs have promising diagnostic utility, with sensitivities for CD above 80%. Significant decreases in serum miRNAs were observed in 24 incident patients with pediatric CD after 6 months of treatment.

CONCLUSIONS

The present study identifies 11 CD-associated serum miRNA with encouraging diagnostic potential. Our findings suggest serum miRNAs may prove useful as noninvasive biomarkers in CD.

MicroRNA let-7f inhibits tumor invasion and metastasis by targeting MYH9 in human gastric cancer

Background

MicroRNAs (miRNAs) are important regulators that play key roles in tumorigenesis and tumor progression. A previous report has shown that let-7 family members can act as tumor suppressors in many cancers. Through miRNA array, we found that let-7f was downregulated in the highly metastatic potential gastric cancer cell lines GC9811-P and SGC7901-M, when compared with their parental cell lines, GC9811 and SGC7901-NM; however, the mechanism was not clear. In this study, we investigate whether let-7f acts as a tumor suppressor to inhibit invasion and metastasis in gastric cancers.

Methodology/Principal

Real-time PCR showed decreased levels of let-7f expression in metastatic gastric cancer tissues and cell lines that are potentially highly metastatic. Cell invasion and migration were significantly impaired in GC9811-P and SGC7901-M cell lines after transfection with let-7f-mimics. Nude mice with xenograft models of gastric cancer confirmed that let-7f could inhibit gastric cancer metastasis in vivo after transfection by the lentivirus pGCsil-GFP- let-7f. Luciferase reporter assays demonstrated that let-7f directly binds to the 3′UTR of MYH9, which codes for myosin IIA, and real-time PCR and Western blotting further indicated that let-7f downregulated the expression of myosin IIA at the mRNA and protein levels.

Conclusions/Significance

Our study demonstrated that overexpression of let-7f in gastric cancer could inhibit invasion and migration of gastric cancer cells through directly targeting the tumor metastasis-associated gene MYH9. These data suggest that let-7f may be a novel therapeutic candidate for gastric cancer, given its ability to reduce cell invasion and metastasis.

Involvement of microRNAs in lung cancer biology and therapy

MicroRNAs (miRNAs) are a class of small RNAs that regulate gene expression. Expression profiles of specific miRNAs have improved cancer diagnosis and classification as well as provided prognostic information in many human cancers, including lung cancer. Tumor-suppressive and oncogenic miRNAs were uncovered in lung carcinogenesis. The biological functions of these miRNAs in lung cancer were validated recently in well-characterized cellular, murine transgenic as well as transplantable lung cancer models, and in human paired normal-malignant lung tissue banks and tissue arrays. Tumor-suppressive and oncogenic miRNAs that were identified in lung cancer will be reviewed here. Emphasis is placed on highlighting those functionally validated miRNAs that are not only biomarkers of lung carcinogenesis but also candidate pharmacologic targets. How these miRNA findings advance an understanding of lung cancer biology and how they could improve lung cancer therapy are discussed in this article.

Circulating MicroRNAs as Minimally Invasive Biomarkers for Cancer Theragnosis and Prognosis

Novel cancer biomarker discovery is urgently needed for cancer theragnosis and prognosis, and among the many possible types of samples, blood is regarded to be ideal for this discovery as it can be collected easily in a minimally invasive manner. Results of the past few years have ascertained the quantification of microRNA (miRNA) as a promising approach for the detection and prognostication of cancer. Indeed, an increasing number of studies have shown that circulating cancer-associated miRNAs are readily measured in plasma or serum and they can robustly discriminate cancer patients from healthy controls, as well as distinguishing between good-prognosis and poor-prognosis patients. Furthermore, recent findings also suggest the potential of circulating miRNAs in the screening, monitoring, and treatment of cancer. This article summarizes the most significant and latest discoveries of original researches on circulating miRNAs involvement in cancer, focusing on the potential of circulating miRNAs as minimally invasive biomarkers for cancer theragnosis and prognosis.