In addition to shaping genome diversification over evolutionary time, L1 retrotransposition alters gene expression as well. The most notable gene altering process involves insertional mutagenesis. The aim of the study was the examination of both nuclear L1 expression levels and cellular localization in cancer cell lines, PBMCs from healthy volunteers and PBMCs from cancer patients. L1 was detected by FISH in chromosome preparations. L1 probe was custom-made using end-point PCR against L1-ORF2 and conjugated with FITC. It was found that cancer cell lines and clinical samples from cancer patients contained significantly elevated levels of L1 per nucleus compared to healthy volunteers. Cytoplasmic L1 was also increased in the above mentioned samples denoting that cancer could be associated with increased L1 activation and mobility. Our results may provide a novel cancer diagnostic marker and highlight the possibility of cytoplasmic L1 inhibition as a therapeutic intervention for cancer.
KeywordsL1CancerRetrotranspositionFISHCytoplasmic
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