miR-21 - A Novel Marker for Cervical Cancer?

Background: Cervical cancer (CC) is the fourth most common cancer in women. Except for HPV, other factors as miRNAs play an important role in carcinogenesis. There were found specific patterns of miRNA, which make them possible tumor biomarkers of CC. Methods: We searched for studies published in the English language in the PubMed database from 2014 to 2021. The following medical subject headings were used: ("miR-21" [Title/Abstract]), ("miRNA-21" [Title/Abstract]), ("microRNA-21" [Title/Abstract]), ("cervical cancer" [Title/Abstract]), ("biomarker" [Title/Abstract]). Only studies that were published as full-text journal articles were used and carefully checked. According to keywords, 35 studies were reviewed. Among them, 2 studies demonstrated overexpression of miR-21 also in other malignancies, and 2 studies described new potential tools for identifying miR-21 as a cancer biomarker. Six review studies were excluded. The last 25 works were reviewed. Results: Totally, in all articles in our table, it was taken 367 samples of CC tissue samples, 45 cervicovaginal lavages, and 25 blood samples in patients with confirmed CC. In all samples of patients with CC, overexpression of miR-21 was confirmed. We reviewed 12 other studies that confirm the role of miR-21 in the development of cervical lesions, but also in the spread of lymph node metastasis and chemoradiotherapy resistance. Conclusion: Demonstrated overexpression of miR-21 in CC cells and recognizing the signaling pathways affected by this molecule suggests using the miR-21 as a suitable non-invasive biomarker of CC.