Lung cancer (LC) is causing more than 1.3 million deaths worldwide annually. Early detection of LC is critical for survival but despite recent advancements in LC diagnostics most patients are still diagnosed at advanced stages of the disease. The situation is further complicated by high intratumor heterogeneity and general diversity of lung malignancies. Insights into cancer genetics have kindled interest in molecular cancer diagnostics. One of the lucrative sources of prospective LC biomarkers is cell-free circulating miRNAs. These small non-coding RNAs are frequently deregulated in LC. It is also known that miRNAs can travel in bodily fluids for extended periods of time, shielded from degradation by membrane vesicles or other biopolymers. Recently, specific subsets of miRNAs associated with tumor phenotypes and disease progression have been found circulating in blood of cancer patients and suggested as potential biomarkers for LC.
In the present study, we have investigated the profiles of circulating miRNAs in blood plasma of LC patients and healthy individuals (HD) in order to identify potential markers for lung cancer diagnostics. Small RNAs were isolated from blood plasma of 20 LC patients and 10 healthy individuals (HD) using protocol reported earlier (Zaporozhchenko et al, Anal Biochem, 2015). Profiles of miRNA expression were obtained using miRCURY LNA miRNA qPCR Panels Plasma/Serum (Exiqon). Ratio based normalization was applied to all miRNA’s with call rate higher than 80%.
Statistical comparison using two-way ANOVA identified 241 ratios (98 individual miRNAs) with significantly different expression between LC patients and HD (p
Based on expression in both data sets 5 ratios containing 7 miRNAs were selected for further validation in an extended cohort of LC and cancer-free individuals.
Clinical trial identification
Legal entity responsible for the study
Laboratory of Molecular Medicine, SB RAS Institute of Chemical Biology and Fundamental Medicine, Novosibirsk, Russian Federation
Study has been supported by Russian Foundation for Basic Research (RFBR, grant No. 14-04-01881), BOR grant VI.62.1.4, and Presidium of RAS research program ‘Molecular and Cellular Biology’ No. 6.1.
All authors have declared no conflicts of interest.