In molecular biology mir-210 microRNA is a short RNA molecule.

MicroRNA MicroRNA (miRNA) are small, single-stranded, non-coding RNA molecules containing 21 to 23 nucleotides. Found in plants, animals and some viruses, miRNAs are involved in RNA silencing and post-transcriptional regulation of gene expression. mi ...

s function to regulate the expression levels of other genes by several mechanisms. mir-210 has been strongly linked with the hypoxia pathway, and is upregulated in response to

Hypoxia-inducible factors Hypoxia-inducible factors (HIFs) are transcription factors that respond to decreases in available oxygen in the cellular environment, or hypoxia. They are only present in parahoxozoan animals. Discovery The HIF transcriptional complex w ...

. It is also overexpressed in cells affected by

cardiac disease Cardiovascular disease (CVD) is a class of diseases that involve the heart or blood vessels. CVD includes coronary artery diseases (CAD) such as angina and myocardial infarction (commonly known as a heart attack). Other CVDs include stroke, hea ...

and

tumour A neoplasm () is a type of abnormal and excessive growth of tissue. The process that occurs to form or produce a neoplasm is called neoplasia. The growth of a neoplasm is uncoordinated with that of the normal surrounding tissue, and persists ...

s. MiRNA-210 in particular, has been studied for its effects in rescuing cardiac function after myocardial infarcts via the up-regulation of angiogenesis and inhibition of

cardiomyocyte Cardiac muscle (also called heart muscle, myocardium, cardiomyocytes and cardiac myocytes) is one of three types of vertebrate muscle tissues, with the other two being skeletal muscle and smooth muscle. It is an involuntary, striated muscle th ...

apoptosis.

Myocardial infarction therapy

Myocardial infarction A myocardial infarction (MI), commonly known as a heart attack, occurs when blood flow decreases or stops to the coronary artery of the heart, causing damage to the heart muscle. The most common symptom is chest pain or discomfort which may ...

is cardiac tissue necrosis that results from occlusion of blood supply via coronary arteries, thereby starving cells of oxygen and nutrients (termed ischemia). Prolong ischemia will eventually kill the cells and the destruction of cardiac cells leads to tissue death, which can lead to heart failure. Delivery of miRNA-210 to an ischemic heart improves heart function, possibly by promoting the release of angiogenic factors like

interleukin Interleukins (ILs) are a group of cytokines (secreted proteins and signal molecules) that are expressed and secreted by white blood cells (leukocytes) as well as some other body cells. The human genome encodes more than 50 interleukins and related ...

-1α (IL-1α), tumor necrosis factor-α (TNF-α) and leptin, as seen in HL-1 cardiomyocytes injected with miRNA-210. However, miRNA-210 also targets the Efna3 and Ptp1b genes, which are genes which endogenously regulate angiogenesis and apoptosis, respectively. Ephrin-A3 (Efna3) is a gene that is involved in the inhibition of angiogenesis. Although it is known that Efna3 inhibits the formation of new blood vessels, its specific role is still unknown. MiRNA-210 suppresses Efna3 at the mRNA level, thereby allowing angiogenesis to occur in cardiac tissue post-infarct. The second target gene,

protein tyrosine phosphatase Protein tyrosine phosphatases (EC 3.1.3.48, systematic name protein-tyrosine-phosphate phosphohydrolase) are a group of enzymes that remove phosphate groups from phosphorylated tyrosine residues on proteins: : proteintyrosine phosphate + H2O = ...

-1B (Ptp1b) is involved in the induction of apoptosis. Ptp1b gene protein has been known to regulate apoptosis by regulating the phosphorylation status of apoptotic proteins such as

caspase-3 Caspase-3 is a caspase protein that interacts with caspase-8 and caspase-9. It is encoded by the ''CASP3'' gene. ''CASP3'' orthologs have been identified in numerous mammals for which complete genome data are available. Unique orthologs are also p ...

and

caspase-8 Caspase-8 is a caspase protein, encoded by the ''CASP8'' gene. It most likely acts upon caspase-3. ''CASP8'' orthologs have been identified in numerous mammals for which complete genome data are available. These unique orthologs are also presen ...

. MiRNA-210 inhibits the effects of Ptp1b protein, which suppresses its pro-apoptotic functions. Therefore, suppression of these two particular genes may contribute to the improvement of cardiac tissue and function by up-regulating angiogenesis and inhibiting apoptosis of cardiomyocytes after myocardial infarct.

Biomarker

Adrenocortical carcinoma

Mir-210 has been suggested as a useful biomarker to distinguish

adrenocortical carcinoma Adrenocortical carcinoma (ACC) is an aggressive cancer originating in the cortex (steroid hormone-producing tissue) of the adrenal gland. Adrenocortical carcinoma is remarkable for the many hormonal syndromes that can occur in patients with ste ...

from adrenocortical adenoma.

Breast cancer

mir-210 expression is associated with survival in breast cancer. Higher expression indicates lower probability for survival in patients with breast cancer.

References

External links

* {{DEFAULTSORT:Mir-210 Microrna MicroRNA Non-coding RNA