Published online Mar 21, 2016. doi: 10.3748/wjg.v22.i11.3202
Peer-review started: September 15, 2015
First decision: November 27, 2015
Revised: December 14, 2015
Accepted: January 9, 2016
Article in press: January 9, 2016
Published online: March 21, 2016
Processing time: 184 Days and 13.8 Hours
AIM: To investigate estrogen receptors expression in duodenal familial adenomatous polyposis (FAP) and any relationship with epithelial proliferation/apoptosis markers.
METHODS: Twenty-two patients affected by FAP undergoing duodenal resection for malignancies were recruited. Controls were 15 healthy subjects undergoing endoscopy for dyspeptic symptoms. ER-α, ER-α, Ki-67, TUNEL and caspase 3 expression (labeling index: percentage of positive cells) were evaluated by immunohistochemistry or immunofluorescence and examined by light or confocal microscopy. Samples were assigned to four groups: normal tissue, low (LGD) and high-grade dysplasia (HGD), adenocarcinoma (AC). One-way analysis of variance, corrected by Bonferroni’s test, and Pearson’s correlation test were applied for statistical analysis.
RESULTS: ER-beta showed a progressive decline: normal tissue (23.5 ± 4.9), LGD (21.1 ± 4.8), HGD (9.3 ± 3.5), AC (7.1 ± 3.1). The normal tissue of FAP subjects expressed ER-beta like the controls (23.9 ± 6.2). Conversely, ER-α showed a progressive increase from normal tissue (24.8 ± 5.6) to AC (52.0 ± 8.2); the expression in normal tissue was similar to controls (22.5 ± 5.3). Ki67 demonstrated a statistically significant progressive increase at each disease stage up to AC. TUNEL did not reveal differences between controls and normal tissue of FAP subjects, but progressive decreases were observed in LGD, through HGD to AC. Pearson’s correlation test showed a direct relationship between ER-β and TUNEL LI (r = 0.8088, P < 0.0001). Conversely, ER-α was inversely correlated with TUNEL LI (r = - 0.7257, P < 0.0001). The co-expression of ER-β and caspase 3 declined progressively from normal to neoplastic tissue.
CONCLUSION: This study confirmed that ER-β is strongly decreased in duodenal FAP carcinomas, declining in a multiple step fashion, thereby suggesting a putative anti-carcinogenic effect. ER-α showed the opposite trend. ER-β/caspase 3 co-expression suggests this hormone’s possible involvement in apoptosis. Hormonal influences in FAP duodenal tumorigenesis, and modulation of these as a possible chemoprevention strategy, may be a promising approach.
Core tip: Familial adenomatous polyposis (FAP) is a genetically inherited disease featuring multiple colonic polyps, with possible duodenal involvement. No study investigating the relationship between estrogen receptors (ERs) and cellular turnover has previously been reported in duodenal FAP patient’s subset. In the present study we found that ER-β is strongly decreased in duodenal FAP carcinomas, in a multiple step fashion suggesting a putative anti-carcinogenic effect. ER-α shows the opposite trend. A possible ER-beta involvement in apoptosis is suggested by its co-expression with caspase-3. The modulation of hormonal influences in FAP duodenal tumorigenesis as a possible chemoprevention strategy may be a promising approach.