The Chemopreventive Effects of Natural Products Against Human Cancer Cells

There is accumulating scientific evidence that many of the natural herbs have medicinal properties that can alleviate symptoms or prevent disease. A growing number of researches have demonstrated that commonly used herbs such as green tea, licorice, Cirisium rhinoceros Nakai, cloves, Terminalia arjuna Linn., Euphorbia jolkini Bioss, Polygonum cuspidatums, Myrica rubra Sieb et Zucc, Centella asiatica, Bupleurum kaoi , Ochrosia elliptica Labill, Stephania tetrandra, and Rhei Rhizoma possess chemopreventive properties that, in some cases, can be used therapeutically. These herbs have been found to possess significant antiproliferative activity against various cancer cells and this activity is supposed to be associated with the modulation of cell cycle progression and induction of apoptosis. In this review, we summarize our findings from studies performed to date regarding the chemopreventive activities of the above-mentioned herbs and their ingredients on the various types of cancer cells.