Agilent has introduced a microarray-based assay for microRNA (miRNA) expression profiling, delivering new levels of sensitivity and specificity and with simple protocols for labelling and detection
Agilent Technologies introduces what it says is the first comprehensive microarray system for expression profiling of human miRNAs.
The assay allows for very small amounts of sample (100ng of total RNA), making it well-suited for miRNA expression profiling experiments.
miRNAs are a class of small non-coding RNAs that are only 19-30 nucleotides long, and are estimated to regulate approximately 30 percent of all human genes.
They were little understood five years ago, but now there are approximately 500 known miRNAs in humans, with ongoing discovery directed toward an estimated 10,000.
Recent studies have shown that distinct miRNA expression patterns are associated with a number of tumor types as well as involved in regulating processes such as cell development, metabolism and viral infections.
Because miRNAs are potential regulators of gene expression, scientists are increasingly interested in measuring them for research, drug discovery, other therapeutics and, eventually, diagnostic tests.
"miRNA profiling is a perfect application for the Agilent microarray platform," said Yvonne Linney, Agilent general manager, genomics.
"Our flexible manufacturing procedure allows us to add new content as new miRNAs are discovered; the multipack format makes this an economical platform; and the high sensitivity achieved with the system enables researchers to detect miRNAs from very small amounts of starting material.
"This application is an important addition to our microarray portfolio, and is synergistic with Agilent offerings for gene expression studies and array-based CGH".
The Agilent miRNA system has been in use by several early access labs around the world over the past six months.
Agilent Laboratories developed the chemistry and probe design, which are used with Agilent's SurePrint in situ synthesis microarray fabrication platform to provide the flexibility and sensitivity demanded by this fast-moving area of research.
This is a good example of how Agilent Labs collaborates with the company's commercial businesses to generate innovative solutions.
"Agilent's platform for miRNA expression profiling includes a straightforward and easy sample-preparation procedure combined with their well established ink-jet printed oligonucleotide arrays," said Zora Modrusan, scientist and head of the microarray laboratory, molecular biology at Genentech.
"An advantage of their technology compared to the other ones is that a very low amount of starting total RNA sample is required, thus enabling miRNA profiling from clinical samples." The Agilent miRNA assays are available in multipack format with eight microarrays printed on a standard 1x3inch slide, which provides economical cost-per-experiment.
The miRNA microarrays are processed using the standard Agilent microarray platform, including hardware and software required for hybridisation, scanning, feature extraction and data analysis.
One-color analysis further simplifies the experimental design.
"Lung cancer is the leading cause of cancer-related deaths in Japan," said Takashi Takahashi, professor of oncology, molecular carcinogenesis at Nagoya University.
"We have shown for the first time that let-7 expression is frequently reduced in lung cancers and that alterations in the miRNA expression may have a prognostic impact on the survival of surgically treated lung cancer patients.
"Agilent miRNA arrays give us the comprehensive miRNA expression profile with excellent performance on sensitivity and accuracy.
"I expect that the studies of Agilent miRNA array may ultimately provide a foundation for a new paradigm of the involvement of miRNA in human oncogenesis".
