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Bioline Launches Latest ISOLATE II miRNA and RNA Purification Kits

Bioline, The PCR Company, a wholly-owned subsidiary of Meridian Bioscience, Inc. (NASDAQ:VIVO), is proud to announce the worldwide release of the latest five kits in the high performance ISOLATE II nucleic acid purification range – ISOLATE II miRNA, Plant miRNA, Biofluids RNA, RNA/DNA/Protein, and FFPE RNA/DNA Kits.

BIDMC Cardiovascular Institute Researchers Will Lead $4 Million NIH Grant to Study MicroRNAs

A cardiovascular research team from Beth Israel Deaconess Medical Center (BIDMC) and Brigham and Women’s Hospital (BWH), led by BIDMC Principal Investigator Saumya Das, MD, PhD, has been awarded a $4 million Common Fund grant from the National Institutes of Health (NIH) as part of a newly formed program on Extracellular RNA Communication. The five-year grant will focus on identifying microRNA biomarkers in heart disease.

Each year, complications from heart attacks (myocardial infarctions) contribute to more than half a million cases of heart failure and 300,000 cases of sudden cardiac arrest, when the heart suddenly stops. Both of these conditions are closely related to a process known as remodeling, in which the structure and function of the heart changes – or remodels — following a heart attack.

“Our goal is to explore the role that microRNAs play in predicting which heart-attack patients will go on to experience complications,” explains Das, an electrophysiologist in BIDMC’s Cardiovascular Institute and co-director of the cardiovascular genetics program within the Outpatient Cardiovascular Clinic.

“Current strategies used to identify the highest risk patients have often been inaccurate,” he adds. “We think that a blood test that makes use of microRNA biomarkers could replace existing strategies and more accurately predict which patients might experience poor outcomes and thereby identify who would most benefit from frequent monitoring and medical care.” Other investigators who are part of the NIH grant, “Plasma miRNA Predictors of Adverse Mechanical and Electrical Remodeling After Myocardial Infarction,” include BIDMC Director of Cardiovascular Research Anthony Rosenzweig, MD, and BWH investigators Raymond Y. Kwong, MD, MPH, and Mark Sabatine, MD, MPH.

microRNAs are one type of extracellular RNA. Once considered nothing more than genomic “junk,” microRNAs have more recently been recognized as playing a key role in cellular functions. Several years ago, scientists began to recognize that these small, noncoding RNAs were not only found inside cells, but could also be found in blood and other tissue fluids.

Using patient plasma samples from extensively characterized patients who have suffered heart attacks, the scientific team will first identify which specific microRNAs are related to poor heart remodeling. They will then use cell culture and animal models of heart disease to further prioritize which microRNAs play a functional role in disease progression. Finally, the investigators will validate these prioritized microRNAs as prognostic markers for poor health outcomes after heart attacks in a large prospective clinical trial.

“Ultimately, we think that miRNA-based tests could replace current tests to predict which patients might be at risk of complications and, therefore, be good candidates to receive an implanted defibrillator,” says Das. “At the same time, we hope to be able to better predict which individuals are at less risk of complications – and thereby spare them unnecessary and costly procedures.”

Beth Israel Deaconess Medical Center is a patient care, teaching and research affiliate of Harvard Medical School, and currently ranks third in National Institutes of Health funding among independent hospitals nationwide.

BIDMC has a network of community partners that includes Beth Israel Deaconess Hospital-Milton, Beth Israel Deaconess Hospital-Needham, Anna Jaques Hospital, Cambridge Health Alliance, Lawrence General Hospital, Signature Health Care, Commonwealth Hematology-Oncology, Beth Israel Deaconess HealthCare, Community Care Alliance, and Atrius Health. BIDMC is also clinically affiliated with the Joslin Diabetes Center and Hebrew Senior Life and is a research partner of Dana-Farber/Harvard Cancer Center. BIDMC is the official hospital of the Boston Red Sox. For more information, visit www.bidmc.org.

Source: Beth Israel Deaconess Medical Center

Droplet Digital PCR Enables Reproducible Quantification of microRNA Biomarkers

A study published online in Nature Methods recently demonstrated that Droplet Digital PCR (ddPCR™) technology can be used to precisely and reproducibly quantify microRNA (miRNA) in plasma and serum across different days, paving the way for further development of miRNA and other nucleic acids as circulating biomarkers.

“In the field of circulating microRNA diagnostics, droplet digital PCR enables us to finally perform biomarker studies in which the measurements are directly comparable across days within a laboratory and even among different laboratories,” said Dr. Muneesh Tewari, Associate Member in the Human Biology Division at the Fred Hutchinson Cancer Research Center and lead author of the study.

Challenges in miRNA quantification

miRNAs are small regulatory RNA molecules with diverse cellular functions. The human genome may encode over 1,000 miRNAs, which could target about 60 percent of mammalian genes. Because they are abundant in many cell types, exist in highly stable extracellular forms, and may provide direct information about disease processes, they are being actively studied as blood-based biomarkers for cancer and other diseases.

Quantitative real-time PCR (qPCR) has been used for the analytical measurement of miRNAs in blood samples; however, researchers have found that qPCR measurements of miRNAs in serum or plasma display unacceptably high interday variability, undermining the use of miRNAs as reliable blood-based biomarkers. An approach that yields more dependable results has therefore been sought by researchers in this field.

Advantages of ddPCR for miRNA detection

Digital PCR has many advantages over qPCR including the ability to provide absolute quantification without a standard curve and robustness to variations in PCR efficiency across different samples and assays. These and other advantages are embodied in Bio-Rad Laboratories’ QX100™ Droplet Digital PCR (ddPCR™) system, which was introduced in 2011.

“We chose to use Bio-Rad’s QX100 Droplet Digital PCR system because it was the first system on the market that could make digital PCR practical from a cost and throughput standpoint for routine use in the lab,” said Dr. Tewari.

To assess the imprecision introduced by each workflow step — serial dilution preparation, reverse transcription (RT), and PCR technical replicates — Dr. Tewari and his team conducted nested analyses of ddPCR vs. qPCR on cDNA from a dilution series of six different synthetic miRNAs in both water and plasma on three separate days. In comparison to qPCR, the researchers found that ddPCR demonstrated greater precision (48–72% lower coefficients of variation) with respect to PCR-specific variation

Next, the team performed a side-by-side comparison of qPCR to ddPCR for detecting miRNAs in serum. They collected sera samples from 20 patients with advanced prostate cancer and 20 age-matched male controls and measured the abundance of miR-141, which has been shown to be a biomarker for advanced prostate cancer. Samples were analyzed by qPCR and ddPCR with individual dilution series replicates prepared on three different days. They found that ddPCR improved day-to-day reproducibility seven-fold relative to qPCR. It was also able to demonstrate differences between case vs. control specimens with much higher confidence than qPCR (p=0.0036 vs. p=0.1199).

“Droplet digital PCR will allow us to accurately follow serum microRNA biomarker concentrations over time during a patient’s treatment course, something that has been nearly impossible to achieve with real-time PCR,” he said.

Study: Absolute quantification by droplet digital PCR versus analog real-time PCR [Nature Methods]

Source: EurekAlert! 

BIDMC Cardiovascular Institute Researchers Will Lead $4 Million NIH Grant to Study MicroRNAs

A cardiovascular research team from Beth Israel Deaconess Medical Center (BIDMC) and Brigham and Women’s Hospital (BWH), led by BIDMC Principal Investigator Saumya Das, MD, PhD, has been awarded a $4 million Common Fund grant from the National Institutes of Health (NIH) as part of a newly formed program on Extracellular RNA Communication. The five-year grant will focus on identifying microRNA biomarkers in heart disease.

Each year, complications from heart attacks (myocardial infarctions) contribute to more than half a million cases of heart failure and 300,000 cases of sudden cardiac arrest, when the heart suddenly stops. Both of these conditions are closely related to a process known as remodeling, in which the structure and function of the heart changes – or remodels — following a heart attack.

“Our goal is to explore the role that microRNAs play in predicting which heart-attack patients will go on to experience complications,” explains Das, an electrophysiologist in BIDMC’s Cardiovascular Institute and co-director of the cardiovascular genetics program within the Outpatient Cardiovascular Clinic.

“Current strategies used to identify the highest risk patients have often been inaccurate,” he adds. “We think that a blood test that makes use of microRNA biomarkers could replace existing strategies and more accurately predict which patients might experience poor outcomes and thereby identify who would most benefit from frequent monitoring and medical care.” Other investigators who are part of the NIH grant, “Plasma miRNA Predictors of Adverse Mechanical and Electrical Remodeling After Myocardial Infarction,” include BIDMC Director of Cardiovascular Research Anthony Rosenzweig, MD, and BWH investigators Raymond Y. Kwong, MD, MPH, and Mark Sabatine, MD, MPH.

microRNAs are one type of extracellular RNA. Once considered nothing more than genomic “junk,” microRNAs have more recently been recognized as playing a key role in cellular functions. Several years ago, scientists began to recognize that these small, noncoding RNAs were not only found inside cells, but could also be found in blood and other tissue fluids.

Using patient plasma samples from extensively characterized patients who have suffered heart attacks, the scientific team will first identify which specific microRNAs are related to poor heart remodeling. They will then use cell culture and animal models of heart disease to further prioritize which microRNAs play a functional role in disease progression. Finally, the investigators will validate these prioritized microRNAs as prognostic markers for poor health outcomes after heart attacks in a large prospective clinical trial.

“Ultimately, we think that miRNA-based tests could replace current tests to predict which patients might be at risk of complications and, therefore, be good candidates to receive an implanted defibrillator,” says Das. “At the same time, we hope to be able to better predict which individuals are at less risk of complications – and thereby spare them unnecessary and costly procedures.”

Source: EurekAlert!

MicroRNAs have diagnostic and prognostic potential in urinary bladder cancer

German researchers have identified four biomarkers that correctly determine malignancy of urinary bladder cancers and contribute to the accurate prediction of patient outcomes. Their results are published in the September issue of The Journal of Molecular Diagnostics.

Current prognosticators of bladder cancer, such as tumor grade, stage, size, and number of foci, have limited usefulness for clinicians since they do not accurately reflect clinical outcomes. Therefore, investigators have been searching for new biomarkers with better diagnostic and prognostic capabilities. Focusing on the role of microRNAs (miRNAs), small non-coding RNAs, researchers have identified four miRNAs that together perfectly discriminated between nonmalignant and malignant tissue, including one alone that classified 81% of the samples correctly. Levels of two miRNAs correlated with overall survival time.

Urinary bladder cancer is the fourth most common cancer in the West. According to the National Cancer Institute, it is estimated that in the United States 72,570 individuals will be diagnosed with and 15,210 will die of cancer of the urinary bladder in 2013. At presentation, in 75% of patients the cancers are confined to the mucosa or submucosa (known as non-muscle invasive bladder cancer, NMIBC), whereas in 25% of cases the cancers have already invaded nearby muscle (muscle-invasive bladder cancer, MIBC).

In a series of experiments, investigators analyzed bladder tissue from patients with NMIBC, MIBC, and nonmalignant bladders. After screening 723 miRNAs by microarray, they selected a subset of 15 distinctively deregulated miRNAs for further validation by real-time quantitative PCR. Seven miRNAs were found to be up-regulated, and eight were down-regulated in malignant bladder tissue samples compared to healthy tissue. Four miRNAs were expressed differently in bladder cancers that invaded muscle compared to those that did not. With one exception, no correlation was found between tumor stage and miRNA levels.

When all 15 of the selected miRNAs were considered together, they correctly classified 100% of tissues as either normal or malignant. Further analysis identified four miRNAs that led to 100% correct classification, and one miRNA (miR-130b) that by itself had an 81% accuracy rate. “These results underline the great potential of miRNAs to serve as diagnostic markers, as previously noted for other urological tumors,” says lead investigator Klaus Jung, MD, the Department of Urology at the University Hospital Charité, Berlin and the Berlin Institute for Urologic Research.

The investigators found that tumor grading could not be correlated with overall survival. Yet, they were able to find two miRNAs that significantly correlated with survival: miR-141 and miR-205. miR-141 showed a trend (P=0.08) of being able to stratify patients with muscle-invasive tumors into two groups with different overall survival times. “This finding could be of clinical importance, but these results must be interpreted cautiously,” says Dr. Jung. “However, previously published studies underline the possible prognostic potential of miRNAs to predict progression and disease-specific or overall survival in bladder cancer patients.”

miRNAs are small non-coding RNAs that contain between 19 and 24 nucleotides. miRNAs regulate gene expression by degrading messenger RNAs or impairing their translation. In recent years there has been a growing interest in miRNAs as potential diagnostic and/or prognostic biomarkers in cancers and other diseases.

Study: miRNA Profiling Identifies Candidate miRNAs for Bladder Cancer Diagnosis and Clinical Outcome [The Journal of Molecular Diagnostics]

Source: EurekAlert!