Detection of HOXA3 gene expression and apoptosis in myocardial tissues of children with tetralogy of fallot / 中华实用儿科临床杂志

ABSTRACT

Objective To explore the potential role of HOXA3 gene in children with tetralogy of fallot (TOF) by detection the expression of HOXA3 mRNA and protein levels,as well as the apoptotic cardiomyocytes in the developing heart tissues.Methods Twenty-two surgical samples from sporadic cases of TOF determined by prenatal color Doppler ultrasound and autopsy [gestational age(25.67 ± 7.68) weeks,TOF group] were examined with quantitative real-time PCR and Western blot to evaluate the expression of HOXA3 gene.Twelve age-matched autopsies without heart structural abnormalities [gestational age (26.55 ± 6.36) weeks,control group] were also included.Terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling(TUNEL) assay was performed to clarify the apoptosis of cardiomyocytes.The difference between the 2 groups and the correlation analysis of HOXA3 level and the apoptotic cardiomyocytes were performed with SPSS 13.0 software.Results Compared with control group,HOXA3 mRNA expression of the outflow tract of the right ventricle from the TOF group was significantly reduced(P ＜ O.01).Western blot also confirmed that the HOXA3 protein was accordingly reduced(P ＜0.01).The proportion of apoptotic cardiomyocytes in samples of TOF group was significantly greater than that of control group (P ＜ 0.01).The proportion of apoptotic cells was strongly correlated with the mRNA and protein expression of HOXA3 (r =-0.566,-0.759,all P ＜ 0.01).Conclusions Reduction of HOXA3 gene expression and the increase of apoptotic cardiomyocytes at the crucial stage during heart development may play a potential role in the onset of TOF.