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| 2 | 2011
Klinisk Biokemi i Norden
(
Fortsætter side 40)
to standardize reporting for miRNA studies and to
identify the optimal mechanism for miR knock down
studies (27). Based on the miR-21 story, there is a risk
that early miRNA work may later be revised when new
and more accurate analytical methods become avail-
able. Several other aspects of miR based therapy also
need to be established such as method of delivery for
miR mimics (agonism) and antimiRs (inhibitors), the
correct dose to use, and more information on off-target
effects. Still, reportedly there are clinical trials already
underway that employ miRNA based therapy (24).
The potential of miRs as future cardiac biomarkers
Diagnosing cardiac disease can be difficult as symptoms
may be diffuse, clinical examination normal, and the
electrocardiogram normal or show only non-specific
alterations, e.g. in the situation of unstable angina pecto-
ris. With limited access to the myocardium for biopsies,
a procedure that may also be harmful to the patient,
there has since long been a search to find circulating
biological markers (biomarkers) to help diagnosing and
risk stratify patients with cardiac disease. The pioneer
work of LaDue and coworkers was first published in
Science in 1954, demonstrating elevated levels of the
enzyme aspartate aminotransferase in patients with
acute myocardial infarction (AMI) (28), and since then a
vast number of circulating markers have been proposed
as new cardiac biomarkers (29). Still, the only mark-
ers that have demonstrated true clinical utility are the
cardiac specific troponins for AMI, and the natriuretic
peptides (BNP/NT-proBNP) for diagnosing HF (29).
Both the troponins and the natriuretic peptides are
protein markers, similar to most other biomarkers in
clinical use, but there is a potential that also substances
besides proteins can provide diagnostic and prognostic
Figure 3. Non-exclusive list of miRNAs altered during cardiac pathophysiology (modified from Røsjø H. Hjerteforum 2009;22:30-39).
