Expression of glucocorticoid receptor isoforms in cutaneous hemangiomas and vascular malformations.

ABSTRACT

BACKGROUND: Hemangiomas are the most common tumors in children. Some hemangiomas may require intervention because of their location, size, behavior, or potential for important complications. Pharmacological therapy with glucocorticoids is the mainstay treatment, but there is no consensus on therapeutic regimens or candidate selection, therapeutic efficacy varies, and the mechanism mediating the beneficial effects of glucocorticoids remains unclear. This study was performed to investigate the expression patterns of the glucocorticoid receptor (GR) and its alpha isoform (GRalpha) in cutaneous hemangiomas and vascular malformations. METHODS: SP immunohistochemical technique was used to examine the expression of GR(e-20) (GR) and GR(p-20) (GRalpha) on vascular endothelial cells in 80 specimens that included 33 proliferating hemangiomas, 32 involuting hemangiomas, 7 vascular malformations as well as 8 normal skin tissues, all obtained from infants and children. GR and GRalpha expression in prepared tissue slides were examined using automated computer-assisted microscopic analysis. Mean gray scale values were compared among the various tumor types. RESULTS: The mean gray scale values of GR were 127.0 +/- 6.4 and 121.4 +/- 6.6 in hemangiomas and vascular malformations respectively, but this difference was not statistically significant (P = 0.104). However, these values were all markedly higher than that of normal skin, which was only 108.6 +/- 6.8 (P = 0.001 and P = 0.000 for comparison with hemangiomas and vascular malformations respectively). The gray scale of GR in proliferation and involuting hemangiomas were 127.9 +/- 4.8 and 126.0 +/- 5.8 respectively, but this difference was not significant (P = 0.146). However, GRalpha expression in hemangiomas, vascular malformations and normal skin declined gradually in stepwise fashion (127.3 +/- 5.4, 120.4 +/- 6.1 and 109.9 +/- 5.3 respectively; P < 0.001). GRalpha expression was higher in proliferating hemangiomas than in involuting hemangiomas (127.2 +/- 6.3 and 122.5 +/- 6.3; P = 0.004). CONCLUSIONS: GR and GRalpha are strongly expressed in hemangiomas and vascular malformations. The expression of GRalpha is closely related to the phase of the hemangioma. Determination of GR and GRalpha may be a positive significance to understand the information of hemangiomas and vascular malformations and may further help determining proper strategies of steroid therapy for hemangiomas and vascular malformations.