In Vitro and in Vivo Antineoplastic Activity of Barbatic Acid

Background: Lichen compounds exhibit remarkable biological activity. Several of them are potent anticancer agent and some with low or none toxicity. The aim of this study was perform in vitro and in vivo assessments of the antineoplastic activity of organic extract and barbatic acid (BAR) isolated from the lichen Cladia aggregata (Sw.) Nyl. Methods: In vitro assays were performed with both extract and BAR against HEp-2 (Adenocarcinoma of the Larynx), NCI-H292 (Squamous Cell Lung Carcinoma) and KB (Nasopharyngeal Squamous Cell Carcinoma) cells. The tests were carried out on the Sarcoma-180 BAR, tumor and organs were analyzed histopatologically after 7 days of chemotherapy. Results: Cytotoxic tests with BAR revealed 50% inhibitory concentration (IC 50 ) of 19.06 µg mL -1 for NCI-H292 and 12.0 µg mL -1 for KB and 6.25 µg mL -1 for HEp-2 cells. Tests with Sarcoma-180 demonstrated 46.3% inhibitory activity against the tumor by BAR. This substance showed no significant effect on the expression of argyrophilic nucleolar organizer regions proteins (AgNORs). The histopathology study of neoplastic tissue, demonstrated that cell proliferation was not affected by the antineoplastic action of the compound tested. Conclusions: The results indicate that barbatic acid exhibits significant antineoplastic activity and low toxicity rate.