Abstract:

The retrotransposon LINE-1 is the largest transposon family of humans with an estimated 500 000 copies representing 17% of the human genome. Meanwhile, it is also the sole autonomous transposon in humans. The reverse transcriptase encoded by LINE-1 is the key component required for its transposition process. Recent evidence suggests that the LINE-1-encoded reverse transcriptase is involved in many important physiological and pathological processes including tumorigenesis. The inhibition of LINE-1-encoded reverse transcriptase inhibits tumor progression, restores cancer cell differentiation and reprograms global transcription profiles. In this review, we summarize newly emerged evidence, and conclude that the LINE-1-encoded reverse transcriptase influences tumorigenesis by shaping the non-coding RNA transcriptomic profile. We hope that this review may shed light on clinical diagnosis and drug development against cancer.

Key words: LINE-1, reverse transcriptase, retrotransposition, non-coding RNA, transcriptomic profile, tumor