Non-coding RNAs (ncRNAs): Their Role in Gene Regulation and Liver Cancer Treatment

Author: Penscriber: Medical & Scientific Writer


Non-coding RNAs (ncRNAs) are RNA molecules that do not encode proteins, unlike messenger RNAs (mRNAs). They are involved in various cellular processes, including regulation of gene expression, RNA splicing, and RNA stability. The discovery of ncRNAs has expanded the view of RNA from being solely a messenger of genetic information to a multifunctional molecule with diverse biological roles.

The most well-known class of ncRNAs are microRNAs (miRNAs), which are approximately 22 nucleotides in length and regulate gene expression by binding to complementary sites on target mRNAs and causing their degradation or repression of translation. Another well-known class of ncRNAs is long non-coding RNAs (lncRNAs), which are transcripts longer than 200 nucleotides and are involved in various processes, such as chromatin modification, transcriptional regulation, and the formation of molecular complexes.

Another important class of ncRNAs is ribosomal RNAs (rRNAs), transfer RNAs (tRNAs), and small nuclear RNAs (snRNAs), which are involved in protein synthesis and the processing of mRNA molecules. piRNAs, which are involved in the regulation of transposable elements and genome stability, and circular RNAs (circRNAs), which are involved in the regulation of gene expression, are also classes of ncRNAs.

ncRNAs have been found to play crucial roles in various biological processes, including development, cell differentiation, stress response, and disease progression. For example, the dysregulation of miRNAs has been implicated in cancer, cardiovascular disease, and neurological disorders, among others. lncRNAs have also been implicated in various diseases, including cancer, neurodegeneration, and cardiovascular disease.

Role of non-coding RNAs in gene regulation

Non-coding RNAs (ncRNAs) are RNA molecules that do not encode proteins, unlike messenger RNAs (mRNAs) but play crucial roles in various cellular processes, including regulation of gene expression. ncRNAs can regulate gene expression at different levels, including transcription, RNA processing, translation, and stability of mRNAs. The following are some of the ways in which ncRNAs regulate gene expression:

Transcriptional regulation: ncRNAs can interact with and recruit transcriptional regulatory proteins to specific genomic regions, leading to the activation or repression of target genes. For example, lncRNAs have been shown to act as molecular scaffolds and recruit chromatin-modifying enzymes to specific genomic regions, leading to changes in the local chromatin structure and the regulation of target genes.

RNA processing: ncRNAs can also regulate gene expression by modulating RNA processing, including alternative splicing and polyadenylation. For example, the expression of certain ncRNAs can lead to the exclusion of specific exons from the mature mRNA, resulting in alternative splicing and changes in the coding capacity of the mRNA.

Translation regulation: ncRNAs can also regulate gene expression by modulating the translation of target mRNAs. For example, microRNAs (miRNAs) can bind to complementary sites on target mRNAs and repress their translation or cause their degradation, leading to reduced expression of target genes.

mRNA stability: ncRNAs can also regulate gene expression by modulating the stability of target mRNAs. For example, the expression of certain ncRNAs can lead to the degradation of target mRNAs, resulting in reduced expression of target genes.


In addition to the above mechanisms, ncRNAs can also regulate gene expression by forming ribonucleoprotein complexes with other RNA-binding proteins, leading to the modulation of gene expression. The regulation of gene expression by ncRNAs has been implicated in various biological processes, including development, cell differentiation, stress response, and disease progression. For example, the dysregulation of miRNAs has been implicated in cancer, cardiovascular disease, and neurological disorders, among others. lncRNAs have also been implicated in various diseases, including cancer, neurodegeneration, and cardiovascular disease.

Role of miRNAs in the treatment of liver cancer

MicroRNAs (miRNAs) are small, non-coding RNA molecules that play important roles in regulating gene expression by targeting messenger RNAs (mRNAs) for degradation or repression of translation. Dysregulation of miRNAs has been implicated in the development and progression of various types of cancer, including liver cancer. The use of miRNAs as therapeutic agents for the treatment of liver cancer has attracted significant attention in recent years, as they have the potential to selectively target genes involved in cancer pathogenesis, offering a novel approach to the treatment of this disease.

Liver cancer is one of the most common cancers worldwide and is a leading cause of cancer-related deaths. Current treatments for liver cancer, including surgical resection, chemotherapy, and radiotherapy, have limited efficacy and are associated with significant side effects. The development of targeted therapies for the treatment of liver cancer has been hindered by a lack of understanding of the molecular mechanisms underlying its development and progression.

miRNAs have been shown to play important roles in the regulation of cell growth, survival, and differentiation in liver cancer. For example, the downregulation of miR-122, a liver-specific miRNA, has been observed in liver cancer, and its restoration has been shown to inhibit cancer cell growth and induce apoptosis. Similarly, the upregulation of oncogenic miRNAs, such as miR-221 and miR-222, has been observed in liver cancer, and their inhibition has been shown to reduce cancer cell growth and induce apoptosis.

miRNA-based therapies for liver cancer can be delivered to target cells in a variety of ways, including direct injection into the liver, intravenous administration, and the use of viral vectors for gene transfer. Direct injection of miRNAs into the liver has been shown to result in selective knockdown of target genes and reduced cancer cell growth and survival. Intravenous administration of miRNAs has been shown to result in selective knockdown of target genes in liver cancer cells, as well as in other organs, demonstrating the potential for systemic delivery of miRNA-based therapies.

Viral vectors have also been used to deliver miRNAs for the treatment of liver cancer, offering the advantage of high transduction efficiency and long-term expression of therapeutic miRNAs. For example, the use of adeno-associated virus (AAV) vectors has been shown to result in the selective knockdown of target genes in liver cancer cells and reduce cancer cell growth and survival.

miRNA-based therapies have several advantages over conventional treatments for liver cancer, including specificity, safety, and potential for combination therapy. miRNAs have the potential to selectively target genes involved in cancer pathogenesis, avoiding the toxicity associated with conventional chemotherapy and radiotherapy. Furthermore, miRNA-based therapies can be combined with other therapeutic modalities, such as chemotherapy, for enhanced efficacy.

10 potential miRNAs candidates for the treatment of liver cancer

Here are ten microRNAs (miRNAs) that have been identified as potential therapeutic targets for the treatment of liver cancer and have been observed to reduce cancer cell growth and induce apoptosis:

miR-122 — Downregulation of miR-122
miR-221/222 — Upregulation of miR-221/222
miR-199a-5p — Downregulation of miR-199a-5p
miR-214 — Upregulation of miR-214
miR-375 — Downregulation of miR-375
miR-192 — Upregulation of miR-192
miR-196a — Upregulation of miR-196a
miR-let-7 — Downregulation of miR-let-7
miR-378 — Downregulation of miR-378
miR-155 — Upregulation of miR-155

These findings suggest that targeting these miRNAs with therapeutic strategies such as miRNA mimics, antimiRs, or RNA interference (RNAi) has the potential to be a promising strategy for the treatment of liver cancer. However, further studies are needed to fully understand the mechanisms underlying the therapeutic effects of miRNAs in liver cancer and to optimize their delivery and efficacy.

In conclusion, miRNAs have the potential to be used as therapeutic agents for the treatment of liver cancer, offering a novel approach to the treatment of this disease. The specificity, safety, and potential for combination therapy of miRNA-based therapies make them attractive candidates for the treatment of liver cancer. However, further studies are needed to fully understand the mechanisms underlying the therapeutic effects of miRNAs in liver cancer and to optimize their delivery and efficacy.

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