Logo image
Overexpression of aromatase associated with loss of heterozygosity of the STK11 gene accounts for prepubertal gynecomastia in boys with Peutz-Jeghers Syndrome
Journal article   Open access   Peer reviewed

Overexpression of aromatase associated with loss of heterozygosity of the STK11 gene accounts for prepubertal gynecomastia in boys with Peutz-Jeghers Syndrome

S. Ham, S.J. Meachem, C.S. Choong, A.K. Charles, G.S. Baynam, T.W. Jones, N.U. Samarajeewa, E.R. Simpson and K.A. Brown
Journal of Clinical Endocrinology & Metabolism, Vol.98(12), pp.E1979-E1987
2013
pdf
overexpression.pdfDownloadView
Published (Version of Record) Open Access
url
Link to Published Version *Subscription may be requiredView

Abstract

Context: Peutz-Jeghers syndrome (PJS) is an autosomal-dominant disorder that arises as a consequence of mutations in the STK11 gene that encodes LKB1. PJS males often have estrogen excess manifesting as gynecomastia and advanced bone age. We and others have previously described an increase in testicular aromatase expression in PJS patients. However, the underlying mechanism has not yet been explored. Objective: The aim of this study was to characterize the role of LKB1 in regulating the expression of aromatase in boys with PJS via signaling pathways involving AMP-activated protein kinase (AMPK) and cyclic AMP-responsive element binding protein-regulated transcription coactivators (CRTCs). Patients: We studied testicular biopsies from two boys with STK11 mutations: a 13-year-old boy and an unrelated 4-year-old boy with prepubertal gynecomastia and advanced bone age, as well as breast tissue from the 13-year-old boy. Results: Loss of heterozygosity of STK11, measured by the absence of LKB1 immunofluorescence, was observed in Sertoli cells of abnormal cords of testis samples from affected individuals. This was associated with loss of p21 expression and decreased phosphorylation of AMPK, known downstream targets of LKB1, as well as the increased expression of aromatase. Similar results of low LKB1 expression in cells expressing aromatase were observed in the mammary epithelium from one of these individuals. Nuclear expression of the CRTC proteins, potent stimulators of aromatase and known to be inhibited by AMPK, was significantly correlated with aromatase. Conclusions: Loss of heterozygosity of the STK11 gene leads to an increase in aromatase expression associated with an increase in CRTC nuclear localization, thereby providing a mechanism whereby PJS results in increased endogenous estrogens in affected males.

Details

UN Sustainable Development Goals (SDGs)

This output has contributed to the advancement of the following goals:

#3 Good Health and Well-Being

Source: InCites

Metrics

123 File views/ downloads
58 Record Views

InCites Highlights

These are selected metrics from InCites Benchmarking & Analytics tool, related to this output

Collaboration types
Domestic collaboration
Citation topics
1 Clinical & Life Sciences
1.26 Diabetes
1.26.1418 Metformin & AMPK
Web Of Science research areas
Endocrinology & Metabolism
ESI research areas
Clinical Medicine
Logo image