Antiproliferative activities of the extracts from Feijoa sellowiana and Psidium cattleyanum

Bladder cancer is a relevant human health problem worldwide. Although a number of chemotherapies are available, many of them present unwanted side effects and are prone to develop resistance to treatment, so they eventually become ineffective, causing low survival rates. The search for selective cytotoxic (antiproliferative) activities on cancer cells from wild plant extracts has markedly increased in recent years. In this work, the antiproliferative effect of total alcoholic extracts of leaf and flowers from feijoa or guayabo del país (Feijoa sellowiana) and arazá (Psidium cattleyanum) was evaluated. Cytotoxic activity was assessed based on resazurin and sulforhodamine B assays on RT4, HT1197 and EJ138 bladder cancer cell lines. The obtained results indicated that an extract of arazá flower (ExAF) showed a strong, concentration-dependent antiproliferative activity. Furthermore, ExAF revealed high selectivity with very low cytotoxic effects on the keratinocyte-derived HaCaT cell line. In this way, ExAF would be a promising candidate for further studying its antitumor activity. These results contribute to the valorization of these native species by expanding their potential use in new technological areas.