Expression of steroidogenic factor-1 and DAX-1 in human adrenocortical tumours

Abstract

Objective To detect mRNA and protein expression of steroidogenic factor-1 ( SF-1 ) and DAX-1 in human adrenocortical tumors and normal adrenal cortex,and to investigate the effect of SF-1 and DAX-1 on the steroidogenesis and development of adrenocortical tumors.Methods Total RNA and protein was extracted from angiotensin Ⅱ unresponsive aldoterone-producing adenomas ( A Ⅱ -U-APA,n =12 ),angiotensin Ⅱ responsive aldoterone-producing adenomas ( AⅡ -R-APA,n =5 ),cortisol-producing adenomas ( CPA,n =10 ),adrenal nonfunctional adenomas ( NFA,n =10 ),aldosterone-producing carcinoma ( APC,n =2 ) and normal adrenal cortex ( NAC,n =8).To analyze gene expression of SF-1,DAX-1,ACTH receptor(ACTHR),and β-actin by real-time quantitative PCR in different tissues.The protein expression of SF-1,DAX-1,and β-actin in the same tissues by Western blot.To study the relationship of ACTHR,SF-1,and DAX-1 with clinical data in adrenocortical tumors.Results The expression of SF-1,DAX-1 mRNA and protein was different in NAC,AⅡ -U-APA,A Ⅱ -R- APA,APC,CPA,and NFA tissues [ relative expression of SF-1 mRNA:24.58±2.45,23.89±3.17,21.59±3.00,(38.75,44.16),14.17±2.80,and 36.38±3.50; DAX-1 mRNA:0.57±0.06,0.37±0.05,0.43±0.05,( 1.52,1.21 ),0.39 ±0.04,and 0.83 ±0.08 ; SF-1 protein:0.76 ±0.11,0.76 ±0.10,0.73 ±0.07,(1.24,1.40),0.55±0.04,and0.98±0.10; DAX-1 protein:0.65±0.14,0.39±0.13,0.43±0.14,(1.18,1.02),0.56±0.04,and 1.03±0.13 ; all P＜0.05 or P＜0.01 ].There was negative correlation by higher SF-1/DAX-1 ratio and tumor size in AⅡ -U-APA tissues.The mRNA and protein expression of SF-1 was lower in CPA and there was the positive correlation with tumor size.Conclusion SF-1 and DAX-1 might play a key role in the development of the adrenocortical tumorigenesis and steroidogenic tissues. Key words: Steroidogenic factor-1; DAX-1; Adrenocortical tumors; Real-time quantitative PCR; Western blot