Aneta Wnęk1, Ewa Andrzejewska1, Józef Kobos2, Katarzyna Taran3, Przemysław Przewratil1. 1. Department of Paediatric Surgery and Oncology, Medical University of Lodz, Sporna str. 36/50, 91-738 Lodz, Poland. 2. Department of Developmental Pathology, Medical University of Lodz, Sporna str. 36/50, 91-738 Lodz, Poland. 3. Department of Pathology, Medical University of Lodz, Pomorska str. 251, 92-216 Lodz, Poland. Electronic address: dr.taran.patho@gmail.com.
Abstract
BACKGROUND: Infantile hemangiomas (IHs) are the most common benign tumors of childhood. They are characterized by a unique clinical course with two phases, proliferation and involution, which are followed by regression. The therapy of infantile hemangiomas was revolutionized in 2008 by the introduction of propranolol, however, the mechanism of its influence on hemangiomas remains unclear. METHODS: The study included 71 patients with IHs, 27 of whom were treated with propranolol while the remaining 44 were used as a comparative group. The expression of Bcl-2, Bax and Caspase3 was determined with immunohistochemistry and mRNA of Bax, Bcl-2 and Caspase3 were assessed with the use of RT-PCR. RESULTS: Both methods revealed a statistically significant decrease in Bcl-2 expression and an increase in Bax in IHs tissues after propranolol treatment. CONCLUSIONS: The results obtained for Bax and Bcl-2 proteins may indicate a link between the effect of propranolol and apoptosis. Higher Bax and lower Bcl-2 expression in the propranolol treated group indicates a strong pro- apoptotic action countering any anti-apoptotic activity; apoptosis was indicted in IH tissue as a potential result of propranolol treatment, with potential clinical impact in other tumors.
BACKGROUND:Infantile hemangiomas (IHs) are the most common benign tumors of childhood. They are characterized by a unique clinical course with two phases, proliferation and involution, which are followed by regression. The therapy of infantile hemangiomas was revolutionized in 2008 by the introduction of propranolol, however, the mechanism of its influence on hemangiomas remains unclear. METHODS: The study included 71 patients with IHs, 27 of whom were treated with propranolol while the remaining 44 were used as a comparative group. The expression of Bcl-2, Bax and Caspase3 was determined with immunohistochemistry and mRNA of Bax, Bcl-2 and Caspase3 were assessed with the use of RT-PCR. RESULTS: Both methods revealed a statistically significant decrease in Bcl-2 expression and an increase in Bax in IHs tissues after propranolol treatment. CONCLUSIONS: The results obtained for Bax and Bcl-2 proteins may indicate a link between the effect of propranolol and apoptosis. Higher Bax and lower Bcl-2 expression in the propranolol treated group indicates a strong pro- apoptotic action countering any anti-apoptotic activity; apoptosis was indicted in IH tissue as a potential result of propranolol treatment, with potential clinical impact in other tumors.