Expression and intracellular localization of progesterone receptors in cultured human gingival fibroblasts.
ABSTRACT The aim of this immunocytochemical study was to characterize the expression and distribution of the progesterone receptor (PR) and estrogen receptor (ER) in gingival fibroblasts using culture cells derived from people at various ages.
The reaction of female hormones is tissue or cell specific, and receptor availability in the cell is one of the major causes for the different reactions. Gingiva is a target tissue for female hormones; however, the characteristics of PR and ER in both the fibroblasts and the other component cells remain largely unknown.
Gingival tissue was obtained from six people at various ages and culture fibroblasts were established. At least three passages of each cell line were strained for PR and ER with monoclonal antibodies (Clone 1A6, Clone 1D5, respectively).
PR positive cells were detected in all six cell lines through early passages to late ones, but ER were only observed in two of six samples with faint reactions. The staining intensity for PR was greater than for ER, but less than that shown in the MCF-7 breast cancer cells, positive control. In every positive control test, ER reactivity was equal to or higher than that of PR. During the interphase, significantly fewer positive fibroblasts occurred compared with negative fibroblasts, and positive nuclei were even fewer. Meanwhile, most of the mitotic cells were PR positive, showing intense localization around chromosomes and on microtubules. These findings suggest that gingival fibroblasts are fundamentally capable of expressing PR and transmit the signal to target genes.
The present study may conclude that in either gender or at any age, gingival fibroblasts express PR rather low in level and do not necessarily localize PR in a nuclear dominant fashion, which is an essential feature for reproductive organ cells. The poor ER reactivity shown in the gingival fibroblasts was discussed in view of the receptor subtype.
Article: Evaluation of Estrogen and Progesterone Receptor Expression in Pyogenic Granuloma and Pregnancy Tumor of Oral Mucosa by Immunohistochemistry[show abstract] [hide abstract]
ABSTRACT: Introduction: Pyogenic Granuloma is a tumorlike lesion of oral cavity that is considered to be non-neoplastic in nature and arises in response to local irritation. Most studies show that this lesion is more common in women than men, possibly because of the vascular effects of female hormones. The purpose of this study was to evaluate the expression of estrogen and progesterone receptors in pyogenic granuloma in pregnant, non-pregnant women and men compared with normal mucosa by immunohistochemistry. Materials & Methods: In this study, cross-sectional analytical 36 paraffin blocks of pyogenic granuloma samples (12 samples of pregnant women, 12 samples of non-pregnant women, 12 samples of men and 9 samples of normal mucosa) were obtained from O.M.F pathology department of Mashhad Dental School. 4 micron sections were prepared and stained by immunohistochemistry staining(Based on Dako factory instruction). After immunostaining, estrogen and progesterone receptors expression in three areas including epithelium, inflammatory and mesenchymal cells were evaluated. The data were analyzed by fisher's exact test. Results: After comparing the expression of estrogen receptors in epithelium(P=0.1), inflammatory cells(P=0.184), mesenchymal cells(P=0.316) in studied groups, no statistically differences were found. Expression of progesterone receptors was not seen in epithelium of any samples and it’s expression in inflammatory and mesenchymal cells was poor(P=0.19,P=0.547). Conclusion: Although estrogen and progesterone receptor expression was observed in pyogenic granulomas of oral mucosa in pregnant, non pregnant women, men and normal mucosa, it did not seem to play an important role in pathogenesis of this lesion or these hormones may have put on effect by other mechanisms other than binding to specific receptors.J Mash Dent Sch. 04/2009; 33(1):63-8.