Quantitative RT-PCR validation of miRNA expression profiling data. Eleven miRNAs that were deregulated in NKTL were selected for validation by quantitative RT-PCR. In every case, miRNAs down-regulated in NKTL compared with normal NK cells were also found to be down-regulated by quantitative RT-PCR. Similar observations were made for up-regulated miRNAs. All comparisons are statistically significant (P < .05).