ncRNAs in fibroblast biology. Pri-miRNAs are processed by Drosha into pre-miRNAs before the endonuclease Dicer generates a mature miRNA. Functional miRNAs are ultimately coupled to Argonaute 2 protein and then incorporated into the RNA-induced silencing complex. When a miRNA and target mRNA are completely complementary, the target mRNA is degraded; when two sequences are partially complementary, the specific gene is silenced through translational suppression of the target mRNA. The mechanism of mRNA regulation by miRNAs depends on the degree of sequence complementarity between the miRNA and 3´UTR motif in the target mRNA gene. One miRNA sequence can target different mRNAs, and the expression of one mRNA sequence can be downregulated by different miRNAs. In contrast, lncRNAs are involved in the proliferation and transformation of cardiac fibroblasts through complementary interactions with DNA, miRNA sponges and indirect or direct regulation of proteins. MiRNAs and lncRNAs are important regulators of intracellular gene expression, and excess synthesis of multiple cytokines, growth factors and chemokines alters the biological activity of CFs, resulting in increased extracellular matrix (ECM) synthesis that leads to cardiac remodeling (By Figdraw).