The Role of MicroRNAs in Lung Cancer: Implications for Diagnosis and Therapy

Lung cancer is the first cause of cancer death in the world due to its high prevalence, aggressiveness, late diagnosis, lack of effective treatment and poor prognosis. It also shows high rate of recurrence, metastasis and drug resistance. All these problems highlight the urgent needs for developing new strategies using noninvasive biomarkers for early detection, metastasis and recurrence of disease. MicroRNAs (miRNAs) are a class of small noncoding RNAs that regulate gene expression post-transcriptionally. These molecules found to be abnormally expressed in increasing number of human disease conditions including cancer. miRNAs could be detected in body fluids such as blood, serum, urine and sputum, which leads us towards the idea of using them as non-invasive biomarker for cancer detection and monitoring cancer treatment and recurrence. miRNAs are found to be deregulated in lung cancer initiation and progression and could regulate lung cancer cell proliferation and invasion. In this review, we summarized recent progress and discoveries in microRNAs regulatory role in lung cancer initiation and progression. In addition, the role of microRNAs in EGFR signaling pathway regulation is discussed briefly.