MicroRNA: A Diagnostic Indicator

A Better Way to Spot Disease MicroRNA in blood could help doctors detect cancer and other conditions, is authored by Courtney Humphries. The article indicates the potential for using blood tests to identify molecular fingerprints evidenced by microRNA which would implicate cancer and disease. Treatment, tailor made to individuals, might become possible because of a blood test. MicroRNAs do not code for proteins like messenger RNAs but instead, bind to messenger RNA and thereby are able to regulate protein synthesis. There seems to be correlations between specific types of microRNA and medical conditions like prostate cancer, for example. If a blood test could substitute for expensive imaging procedures and invasive biopsies, the advantages would be evident. Quoting the source:

In a new paper, published in Cell Research, scientists give the first comprehensive tally of microRNAs in blood serum and identify patterns of microRNAs that distinguish patients with two kinds of cancer and diabetes from healthy subjects. The researchers used sequencing technology to identify the type and levels of microRNAs in the blood serum of healthy people, and they found that these measurements are consistent from individual to individual. Next, they looked at the types of microRNAs and the levels in patients with lung cancer, colorectal cancer, and diabetes. For each condition, the researchers identified a unique pattern of microRNA expression that differed from that of healthy people.

Lead author Chen-Yu Zhang says that many scientists were surprised to discover that microRNA can be measured in blood serum, because the blood also contains ribonuclease, an enzyme that digests RNA. Although it's not yet clear how microRNAs escape destruction and persist in the blood, Zhang says, "whatever the reason, microRNAs are stable in the serum and are resistant to ribonuclease digestion."