Circulating miRNA-30a and miRNA-221 as Novel Biomarkers for the Early Detection of Non-Small-Cell Lung Cancer

Background: Detecting non-small-cell lung cancer at an early stage has become a great challenge due to the lack of a specific non-invasive marker. MicroRNAs are small, non-coding RNA molecules that play a role in carcinogenesis and cancer progression, as indicated by their abnormal expression in the patients’ plasma. Herein, we investigated the plasma level of circulating miRNA-30a and miRNA-221 as non-invasive markers for an early detection of non-small-cell lung cancer. Method: A cross-sectional study was conducted at Assiut University Hospital, Egypt, to investigate miRNA-30a and miRNA-221 expression via quantitative real-time PCR in the plasma of patients with non-small-cell lung cancer (n=70) and healthy controls (n=34). Receiver operating curves were used to evaluate the diagnostic value of miRNA-221 and miRNA-30a in non-small-cell lung cancer. The relationship between both markers and patient clinical parameters was further assessed. Result: Circulating plasma miRNA-30a and miRNA-221 levels were significantly higher in the non-small-cell lung cancer patients compared with those in the healthy controls (P<0.05). There was a significant difference regarding the plasma miRNA-30a level among the three groups (the highest levels were recorded in adenocarcinoma, followed by large cell carcinoma and squamous cell carcinoma). ROC curve analysis of miRNA-30a and miRNA-221 showed that specificity and sensitivity were 60% and 80%, and 40% and 75%, respectively. Conclusion: miRNA-30a and miRNA-221 may be non-invasive biomarkers for early detection and screening or therapeutic targets in patients with NSCLC. Future studies are warranted regarding the use of biomarkers as therapeutic targets.