High throughput screening of natural products for anti-mitotic effects in MDA-MB-231 human breast carcinoma cells.

Some of the most effective anti-mitotic microtubule-binding agents, such as paclitaxel (Taxus brevifolia) were originally discovered through robust NCI botanical screenings. In this study, a high-through microarray format was utilized to screen 897 aqueous extracts of commonly used natural products (0.00015–0.5 mg/ml) relative to paclitaxel for anti-mitotic effects (independent of toxicity) on proliferation of MDA-MB-231 cells. The data obtained showed that less than 1.34 % tested showed inhibitory growth (IG50) properties <0.0183 mg/ml. The most potent anti-mitotics (independent of toxicity) were Mandrake root (Podophyllum peltatum), Truja Twigs (Thuja occidentalis), Colorado desert mistletoe (Phoradendron flavescens), Tou Gu Cao Speranskia Herb (Speranskia tuberculata), Bentonite Clay, Bunge Root (Pulsatilla chinensis), Brucea Fruit (Brucea javanica), Madder Root (Rubia tinctorum), Gallnut of Chinese Sumac (Melaphis chinensis), Elecampane Root (Inula Helenium), Yuan Zhi Root (Polygala tenuifolia), Pagoda Tree Fruit (Melia Toosendan), Stone Root (Collinsonia Canadensis) and others such as American Witchhazel, Arjun and Bladderwrack. The strongest tumoricidal herbs identified from amongst the subset evaluated for anti-mitotic properties were wild yam (Dioscorea villosa), beth-root (Trillium Pendulum) and alkanet-root (Lithospermum canescens). Additional data was obtained on a lesser-recognized herb: (Speranskia tuberculata) which showed growth inhibition on BT-474 (human ductal breast carcinoma) and Ishikawa (human endometrial adenocarcinoma) cells with ability to block replicative DNA synthesis leading to G2 arrest in MDA-MB-231 cells. In conclusion, these findings present relative potency of natural anti-mitotic resources effective against human breast carcinoma MDA-MB-231 cell division.