Essential Oil of Tridax procumbens L Induces Apoptosis and Suppresses Angiogenesis and Lung Metastasis of the B16F-10 Cell Line in C57BL/6 Mice

Abstract

To determine the effect of essential oil obtained from a traditionally used medicinal plant Tridax procumbens L, on lung metastasis developed by B16F-10 melanoma cells in C57BL/6 mice. Parameters studied were toxicity, lung tumor nodule count, histopathological features, tumor directed capillary vessel formation, apoptosis and expression levels of P53 and caspase-3 proteins. In vitro the MTT assay showed cytotoxicity was found to be high as 70.2% of cancer cell death within 24 hrs for 50 μg. In vivo oil treatment significantly inhibited tumor nodule formation by 71.7% when compared with untreated mice. Formation of tumor directed new blood vessels was also found to be inhibited to about 39.5%. TUNEL assays also demonstrated a significant increase in the number of apoptotic positive cells after the treatment. P53 and caspase-3 expression was also found to be greater in the essential oil treated group than the normal and cancer group. The present investigation showed significant effects of the essential oil of Tridax procumbens L in preventing lung metastasis by B16F-10 cell line in C57BL/6 mice. Its specific preventive effect on tumor directed angiogenesis and inducing effect on apoptosis warrant further studies at the molecular level to validate the significance of Tridax procumbens L for anticancer therapy.