Quantitative reverse transcriptase real-time polymerase chain reaction (qRT-PCR) in translational oncology: lung cancer perspective.

Quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) is rapidly becoming a basic method in lung cancer research. Analysis of transcriptional activity of tumor cells or detection of tumor markers by this technique has the potential to change lung cancer diagnosis and treatment. Quantitative RT-PCR is characterized by unparalleled sensitivity and specificity, with very reliable reproducibility. Its prime advantage for gene expression analysis is its broad dynamic range of 10(7)-fold. Moreover, it is cost-effective, feasible in every day laboratory routine and efficient in terms of biological material consumption. Still, there are a number of methodological aspects that need to be carefully considered before it can sensibly be implemented into clinical practice. Three major technical issues: the choice of chemistries, gene expression data normalization and statistical processing of the results will be specifically highlighted in this review. Further, clinical applications of qRT-PCR will be thoroughly discussed: detection and staging of lung cancer and construction and validation of prognostic and predictive gene expression signatures.