Diagnostics & Imaging Week

In recent years scientists have linked microRNA (miRNA) sequences to diseases, including cancer and heart disease, but the therapeutic outcomes of these discoveries are not always clear.

Case in point: researchers from Invitrogen (Carlsbad, California) say they have linked miRNA sequences to colorectal cancer using RNA samples from BioServe (Beltsville, Maryland). The information could someday be used to develop a diagnostic test, but for now it is simply being called a "great research study" and the companies are not sure exactly what will come of it.

Chris Adams, R&D leader of epigenetics at Invitrogen, told Diagnostics & Imaging Week that his group agreed to use its genetic-profiling technology to profile about a dozen samples from colorectal cancer tissue and adjacent healthy colon tissue from the same patient.

Through this research collaboration, the scientists reportedly identified noncoding RNAs that were differentially expressed in healthy and diseased tissue using Invitrogen's Ncode Profiler software and RNA samples from BioServe's OncoRNA product line. These miRNA sequences were either up or down-regulated between matched samples of RNA isolated from healthy colon and colorectal cancer tissues.

The companies presented data from the project in a poster at the annual meeting of the American Association of Cancer Research (Philadelphia) last month in San Diego.

"Using the high-quality RNA samples from BioServe, we were able to identify novel microRNA sequences that could potentially be involved in the generation of new tumor tissues, particularly in colorectal cancer," Adams said.

"The next step obviously would be to validate these markers that we've uncovered ... once these markers are validated than they become potential biomarkers that could be incorporated in a diagnostic test," he told D&IW.

But for now, BioServe simply wanted to demonstrate the value of its RNA samples for potential downstream applications, and Invitrogen's motive for doing the research was to show that its technology is applicable to finding biomarkers that could be used later on for diagnostic or therapeutic development.

"We're always looking for ways to say 'look, here's a downstream application that shows value of these microRNA samples,'" BioServe CEO Kevin Krenitsky told D&IW. He said the research project was important, even as a stand-alone piece of information.

"I think it's a nice example of a collaboration where everybody wins because you're producing interesting data," Krenitsky said.

MicroRNAs are short RNA sequences that do not code for specific proteins but, according to BioServe, are "extremely important" in the regulation of gene expression. Among the activity of miRNAs is the triggering of messenger RNA (mRNA) degradation and the inhibition of protein translation — the process of assembling amino acids into proteins based on the instructions contained in mRNA sequences, the company said.

According to Invitrogen, its Ncode Human miRNA microarray V3 consists of miRNA content from multiple sources, including the Sanger 10.0 miRNA database and new miRNAs unavailable in public databases, giving users access to strong content for identification and study of miRNAs.

BioServe's OncoRNA product line is a series of RNAs isolated from fresh-frozen, fully annotated tumor and adjacent normal tissues, to probe the Ncode Human miRNA microarray V3.

"MicroRNA is making headlines in drug discovery for its ability to fine-tune the activity of genes and its part in the formation of cancer," Krenitsky said. "This makes it all the more critical that researchers can be certain they are working with stable, highly annotated samples collected under rigorous ethical and scientific protocols. We created OncoRNA to respond to this need, providing bench-ready RNA for tomorrow's discoveries."

BioServe says it collaborates with pharmaceutical, biotech and diagnostic firms to identify and validate markers that cause disease while correlating clinical and molecular data to develop new diagnostic tests "promoting wellness around the world."

The company offers the Global Repository, a library of more than 600,000 human DNA, tissue and serum samples linked to detailed clinical and demographic data from 140,000 consented and anonymous patients from four continents.

Invitrogen provides products and services intended to support academic and government research institutions and pharmaceutical and biotech companies in "efforts to improve the human condition."