Overexpression of phosphorylated-ATF2 and STAT3 in cutaneous angiosarcoma and pyogenic granuloma.

BACKGROUND: Activating transcription factor-2/Activator protein-1 (AP-1), Signal transducer and activator of transcription-3 and p53 are important regulators of cellular proliferation, apoptosis, differentiation in the pathogenesis of many human tumors, but the expression of phosphorylated (p)-activating transcription factor-2 (p-ATF2), phosphorylated (p)-signal transducer and activator of transcription-3 (p-STAT3) and p53 family (p63 and p73) has not been investigated in cutaneous angiosarcoma (CAS) and pyogenic granuloma (PG) so far.

OBJECTIVES: To investigate the expression of p-ATF2, p-STAT3 and p53 and its family in cutaneous vascular tumors (CAS and PG).

METHODS: Paraffin-embedded specimens of 14 CAS and 19 PG were subjected to immunohistochemical staining for p-ATF2, p-STAT3, p53, p63 and p73.

RESULTS: P-ATF2 was expressed in 13 out of 14 CAS and in all of 19 PG. P-STAT3 was expressed in all of 14 CAS and 19 PG. P53 was expressed in all of 14 CAS and 19 PG, while both p63 and p73 were negative in CAS and PG. The p-ATF2-, p-STAT3- and p53 expression (% positive cells) in CAS and PG were significantly higher than in normal dermal vessels, but none of these transcription factors distinguished malignant (CAS)- from benign (PG) vascular tumor.

CONCLUSIONS: The present study suggests that overexpression of p-ATF2, p-STAT3 and possibly p53, but not p63 or p73, may contribute to the tumorigenesis of cutaneous vascular tumors.