PIWI-Interacting RNAs (piRNAs) are small non-coding RNA molecules of approximately 24–32 nucleotides in length that often bind to members of the piwi protein family to play regulatory roles. Recently, emerging evidence suggests that in addition to the mammalian germline, piRNAs are also expressed in a tissue-specific manner in a variety of human tissues and modulate key signaling pathways at the transcriptional or post-transcriptional level. piRNAs have been shown to participate in the epigenetic regulation of cancer and other diseases and are key elements of cellular homeostasis. Furthermore, they play an important role in tumor formation, proliferation, and migration of the cells. Similar to miRNAs, piRNAs posttranscriptional regulation occurs in the cytoplasm. Numerous studies have suggested that piRNA and PIWI proteins, which are abnormally expressed in various cancers, may serve as novel promising biomarkers and therapeutic targets for tumor diagnostics and treatment.
Based on the levels of piR-5937 and piR-28876, it was possible to differentiate between cancer patients and healthy donors with high sensitivity and specificity. Moreover, both piRNAs exhibited satisfactory diagnostic performance also in patients with stage I disease and enabled detection of colon cancer with higher sensitivity than currently used biomarkers CEA and CA19-9.
- References to piR-5937