Evaluation of antitumor and cytotoxic activity in vitro of latex Vasconcellea quercifolia A. St.-Hil. (Caricaceae)

Abstract

The high cancer rate that affects the population nowadays and the adverse effects of treatments make it important to search for new drugs obtained by researching the biodiversity potential of each country. Vasconcellea quercifolia A. St.-Hil. is a species of the family Caricaceae, native to Brazil with high latex production. Other species of the same family have already proven to have antitumour activity. Thus, this study evaluated the effect of the aqueous fraction of the latex extracted from the green twigs and fruits of V. quercifolia on the viability of squamous neoplastic lines of human uterine cervix (SiHa), breast adenocarcinoma (MCF-7), and non-tumour immortalized human keratinocytes (HaCat). Cells were cultured in Dulbecco's modified Eagle's medium (DMEM) with 10% foetal bovine serum (FBS) maintained at 5% CO2 and 37 °C, and were treated with different concentrations of the aqueous fraction of latex (0 to 310 μg mL−1). Results showed that the treatment induced an inhibition of 91.6% and 50.8% in the viability of SiHa and MCF-7 cells, respectively, with an IC 50 of 18.98 μg mL−1 for the SiHa strain and 48.82 μg mL−1 for the MCF-7 lineage. In the non-tumour lineage (HaCat), the treatment induced an inhibitory effect of approximately 50% at concentrations above 22 μg mL−1. Despite these findings, this study emphasizes the relevance of additional studies involving V. quercifolia latex as a potential therapeutic alternative against the tumours evaluated. It is worth noting that this study is the first related to cytotoxic and antitumour activities in vitro using latex from this species.