How can microRNAs contribute to cancer development?
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Nucleic acid
A portion of the polynucleotide chain of deoxyribonucleic acid (DNA), with an inset showing the corresponding pentose sugar and pyrimidine base in ribonucleic acid (RNA).
MicroRNAs (miRNAs) contribute to cancer development through the aberrant regulation of gene expression. As noncoding RNA molecules, miRNAs typically function by binding to messenger RNA (mRNA), which leads to the degradation of the mRNA or the repression of protein synthesis.12
In the context of cancer, miRNAs can act in two primary ways depending on the genes they target:1
- Oncogenes: Some miRNAs function as oncogenes by downregulating tumor suppressor genes, thereby promoting uncontrolled cell proliferation and tumor progression.12
- Tumor Suppressors: Conversely, other miRNAs act as tumor suppressors by inhibiting the expression of genes that drive cell growth. When these miRNAs are dysregulated or lost, the resulting increase in target gene activity can facilitate tumorigenesis.12
Ultimately, the role of a specific miRNA in cancer depends on whether it upregulates or downregulates key genes involved in fundamental processes like cell growth, differentiation, and death.1