We used real-time quantitative reverse transcription-polymerase chain reaction (RT-PCR) using the LightCycler to monitor the TS and DPD gene expression levels in thymoma tissue specimens from patients, coamplified with glyceraldehyde-3-phosphate dehydrogenase (GAPDH) as an internal standard.
The TIMP-1/GAPDH mRNA expression level was significantly higher in invasive (stage II-IV) thymomas (means +/- SE, 81.4 +/- 28.1) than in noninvasive (stage I) thymomas (30.9 +/- 8.3, P = 0.026).