Identification of the reference genes' accuracy for lung tissue specimens by real-time quantitative PCR / 肿瘤研究与临床

ABSTRACT

Objective To analyze the expression stability of the three widely used reference genes β-glueuronidase (GUSB), glycera]dehydes-3-phosphate dehydrogenase (GAPDH), β2-microglobulin (β2-M) in Chinese lung cancer tissue specimens and normal lung tissue specimens. Methods Gene expression wasmeasured by quantitative real time PCR and expression stability was analyzed with two widely used softwares genorm and normfinder. Results The intra-and inter-group difference of GAPDH is maximum (The intra and inter-group s is 1.07 and 0.93 respectively, |△ Ct|=2.01±1.06; P =0.000). The mean of these three genes' Ct value is the most stable one analyzed by the two softwares. But the t test showed that the mean of Ct value of GUSB and β2-M is the unique combination that had the minimum intra-and inter-group difference, with no statistically significant differences between normal and malignant samples (The intra-and inter-group s is 0.53 and 0.79 respective]y, |△Ct|= 0.73±0.53; P =0.053). Conclusion It is inappropriate to normalize data derived from lung tissue specimens using one of these three housekeeping genes alone. Among the different combinations of these three genes, the mean of the Ct values of GUSB and β2-M is the best choice as the internal control of lung tissue specimens.