Atividade antineoplásica do extrato da polpa da Annona crassiflora em células de carcinoma epidermoide de boca

Abstract

Annona crassiflora Mart., a plant native to the Brazilian cerrado, is used by folk medicine to treat various pathological conditions. Recent studies have shown that extracts from different parts of A. crassiflora exhibit biological activities. This study aimed to investigate the antineoplastic potential of butanol extract of pulp fruits of A. crassiflora on neoplastic behavior of oral squamous cell carcinoma (OSCC) cells and molecular mechanisms evolved. The OSCC immortalized cell lines (SCC-9 and SCC-4) were treated with butanol extract of A. Crassiflora for analysis of proliferation, migration, cell death, coculture, apoptosis, immunocytochemistry, ROS and cell cycle. DPPH test revealed a high antioxidant capacity. The butanol extract decreases the cell proliferation by reduction of the population in the synthesis phase (10 and 100 µg/ml) and cell cycle arrest in the G2/M phase (10 µg/ml). Furthermore, treatment significantly increased the death of cells exposed to treatment with 100 µg/ml, and also led to an increase in the expression of caspase-3, ROS generation and cell population in late apoptosis and necrosis. The migration capacity of OSCC cells was impaired. In coculture assay between SCC-9 and endothelial cells HUVEC, the butanol extract prevented the proliferation of cells of both cell lines at 100 µg/ml. Analysis of HPLC chromatographic fractions isolated from butanol extract showed that only two fractions revealed an antineoplastic role, impairing cell proliferation. Thus, butanol extract of A. crassiflora and some of its chromatographic fractions demonstrated a relevant role to control the neoplastic behavior of OSCC; it is crucial to conduct further studies to characterize the specific bioactive compounds contained in the fruit.