There is a growing body of evidence that microRNAs appear in different concentrations in healthy cells versus diseased cells. Thus, measuring and altering the amount of microRNAs in cells could be a promising tool in diagnosis and therapy for a range of diseases.
Drug discovery stemming from microRNAs is very different from the anything attempted so far. Since microRNAs are natural inhibitors of the production of specific proteins they open up a completely new avenue of therapeutic approach.
Under the terms of the agreement, biopharmaceutical company, Rosetta Genomics, will provide Ambion access to proprietary microRNA (miRNA) sequences discovered and owned by Rosetta Genomics.
The agreement enables Ambion to adapt its microRNA platforms to detect, quantify, and characterise Rosetta Genomics' proprietary microRNA sequences.
"Identifying and understanding the role of microRNAs in human health represents a new frontier in research making it possible to examine the roles of microRNAs in neural development, immune response, viral infection, and oncogenesis," said Matt Winkler, chief executive officer of Ambion.
MicroRNA molecules are a recently discovered class of small RNA molecules that are critical in the development and life cycles of humans, animals, and plants. MicroRNAs are major regulators of global gene expression and likely play significant roles in the manifestation of many disease states.
Recent evidence indicates that microRNAs play a critical role in the development of cancer and certain viral infections.
Indeed, drug development as a result of microRNAs is different from current approaches, as well as from the siRNA and antisense approach.
Contemporary drugs are designed to target proteins of our body. However, their non-discriminate nature means drugs are non-specific in many cases. This is one reason why many drugs have unwanted side effects.
It has been estimated that 95 per cent of all drugs are designed to decrease target protein levels and there are virtually no drugs available to increase levels of beneficial proteins, which are missing in a disease state.
The RNA interference (RNAi) and antisense approach target the protein machinery by destroying the mRNA and not by targeting the protein itself. However, they still are inhibitors of protein production and cause a reduction in the amount of bad proteins.
Their specificity and the ability to focus on difficult target proteins are their main advantage in drug development.
It's not all good news. The RNAi/antisense approach is further limited, as they still offer no breakthrough for increasing levels of "good" proteins.
However, the theory is that by inhibiting specific microRNAs a drug can cause an increase in the expression of beneficial proteins that will restore normality to disease cells, a possibility virtually non-existent in any other drug discovery avenue.
Moreover, they also hold strong benefits for drugs aimed at increasing protein levels. They have evolved to become the ideal inhibitors of the activity of their target mRNAs.
Many microRNAs are believed to regulate groups of mRNAs. Such a regulation may be advantageous since the use of one microRNA as a drug will result in the inhibition of a group of mRNAs, providing a novel approach to disease treatment. In contrast, RNAi approaches target a single mRNA.
Since RNAi are not natural inhibitors, but rather synthetic molecules, and since they work though a different inhibition mechanism, they do not have the ability to inhibit a group of diverse genes that participate together in causing disease phenotypes.