A universal linker-RT PCR based quantitative method for the detection of circulating miRNAs

Circulating miRNAs have been identified as key regulators of gene expression in many physiological and pathological processes. Real-time quantitative PCR is a conventional method that is indispensable, although many different approaches have been employed for miRNA expression profiling. We have established a universal, sensitive, highly efficient, cost effective and time-saving reverse transcription quantitative PCR for the measurement of circulating miRNA. This method involves the use of a random pre-adenylated DNA oligonucleotide linked to miRNAs followed by a universal reverse transcription and individual miRNA quantitative process. This method was optimized, and its specificity and sensitivity were evaluated. Circulating miRNAs from lung cancer patients were detected for verification. The results suggest that this random pre-adenylated DNA oligo-based miRNA quantitative method is sufficiently efficient and sensitive to detect circulating miRNA.