Related Experiment Video

Updated: Apr 19, 2026

RNA Next-Generation Sequencing and a Bioinformatics Pipeline to Identify Expressed LINE-1s at the Locus-Specific Level
11:04

RNA Next-Generation Sequencing and a Bioinformatics Pipeline to Identify Expressed LINE-1s at the Locus-Specific Level

Published on: May 19, 2019

10.6K

Regulatory roles of LINE-1-encoded reverse transcriptase in cancer onset and progression

Ilaria Sciamanna, Alberto Gualtieri, Pier Francesco Piazza

    Oncotarget
    |December 6, 2014
    PubMed

    Insights

    LINE-1 reverse transcriptase (RT) is active in tumors, driving cancer progression. Inhibiting this enzyme restores normal cell function and miRNA profiles, revealing a novel mechanism in tumorigenesis.

    Area of Science:

    • Molecular Biology
    • Genetics
    • Cancer Research

    Background:

    • LINE-1 retrotransposons encode reverse transcriptase (RT), crucial for their mobility.
    • LINE-1 RT expression is typically inhibited in differentiated tissues but active in tumors.
    • Abnormal LINE-1 RT activity is implicated in cancer cell transcriptome dysregulation.

    Purpose of the Study:

    • To investigate the role of LINE-1-encoded reverse transcriptase (RT) in cancer.
    • To explore how LINE-1 RT activity impacts gene expression and microRNA (miRNA) biogenesis in tumors.
    • To determine if inhibiting LINE-1 RT can restore normal cellular function and suppress tumor progression.

    Main Methods:

    • Experimental inhibition of LINE-1-derived reverse transcriptase (RT) in cancer cells.
    • Analysis of global transcription profiles following RT inhibition.
    • Assessment of miRNA biogenesis and regulatory networks.
    • Evaluation of tumor progression and cell differentiation markers.

    Main Results:

    • Inhibition of LINE-1 RT restored differentiation in cancer cells.
    • RT inhibition led to globally reprogrammed transcription profiles.
    • LINE-1 RT was found to modulate miRNA biogenesis by affecting regulatory RNA production.
    • RT inhibition normalized aberrant miRNA profiles and regulatory networks in cancer cells.
    • LINE-1 RT activity was identified as a key regulator in tumorigenesis.

    Conclusions:

    • LINE-1-encoded reverse transcriptase (RT) plays a critical role in tumorigenesis through transcriptome and miRNA regulation.
    • Inhibiting LINE-1 RT activity offers a potential therapeutic strategy by restoring normal cellular mechanisms.
    • This study uncovers a previously unrecognized RT-dependent mechanism impacting cell fates in cancer.

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