Elementary studies on elevated steroidogenic factor-1 expression in aldosterone-producing adenoma.
OBJECTIVE
The expression of steroidogenic factor-1 (SF-1) was elevated in adrenal aldosterone-producing adenoma (APA). The influence of SF-1 on adrenal tumorigenesis by adrenocortical cell line H295R cells was investigated.


METHODS
Real-time PCR and Western blotting were used to detect SF-1 expression in 16 APA samples and 12 normal adrenal samples. Specific SF-1-shRNA plasmid was transfected into H295R cells to inhibit SF-1 expression. Western blotting and real-time PCR were used to verify the effects of RNAi on SF-1 inhibition. Subsequently, WST-1 and cell count were applied to evaluate cell proliferation at different SF-1 levels. Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining was used to measure cell apoptosis, and proliferation marker Ki-67 was studied by immunohistochemistry.


RESULTS
Compared with normal adrenal samples, SF-1 mRNA and protein levels in APA samples were significantly higher. It was 10.48:1 at SF-1 mRNA and 0.87 ± 0.05 vs. 0.39 ± 0.07 at protein levels, respectively (P < 0.01). A decreased SF-1 significantly inhibited cell proliferation in the experimental and control cells. These results were supported by weaker Ki-67 staining in SF-1-inhibited cells [(36.9% ± 4.17%) vs. (58.48% ± 7.16%) (P < 0.01)]. Moreover, SF-1 inhibition induced a 2.7-fold increase in the percentage of apoptotic H295R cells (P < 0.01).


CONCLUSIONS
Elevated SF-1 may play an important role in APA formation and primary aldosteronism. SF-1 acts as an oncogenic factor, and its inhibition provides new insight into the understanding and treatment of related adrenal diseases.
Hu
Dongliang
D
Department of Urology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
Ouyang
Jinzhi
J
Wu
Zhun
Z
Shi
Taoping
T
Wang
Baojun
B
Ma
Xin
X
Li
Hongzhao
H
Wang
Shaogang
S
Zhang
Xu
X
D000306:Adrenal Cortex Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D018246:Adrenocortical Adenoma / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D000450:Aldosterone / Q000096:biosynthesis*; D017209:Apoptosis; D015153:Blotting, Western; D002460:Cell Line; D049109:Cell Proliferation; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007150:Immunohistochemistry; D019394:Ki-67 Antigen / Q000032:analysis; D008856:Microscopy, Fluorescence; D034622:RNA Interference; D020133:Reverse Transcriptase Polymerase Chain Reaction; D054339:Steroidogenic Factor 1 / Q000235:genetics / Q000378:metabolism*
D019394:Ki-67 Antigen; D054339:Steroidogenic Factor 1; D000450:Aldosterone