Cancer is a common name for more than 100 diseases that can occur in any part of the body. It is one of the malignant diseases that seriously affect human health at present. According to the World Health Organization (WHO), there were 14.1 million new cancer cases and 8.2 million cancer deaths worldwide in 2012, compared with 12.7 million and 7.6 million respectively in 2008. It is expected that by 2030, the global incidence of cancer will reach 27 million and the mortality rate will reach 13.2 million.

There are many factors that cause cancer, external cause are Physical carcinogens, chemical carcinogens, biological carcinogens, and internal cause are body immune function decline, family genetic history. In view of the high incidence and mortality of cancer, its prevention and treatment has always been the focus of researchers inside of country and abroad. After decades of development, many drugs have been used to prevent cancer and fight cancer. These drugs can be divided into chemical synthesis, biosynthesis, natural product extraction and so on. Many chemosynthetic anticancer drugs have toxic and side effects on normal human cells, so it is still one of the hot topics in recent years to find low-toxic and highly effective anticancer active ingredients from natural animals and plants.

Medical experiments and clinical applications show that:

1, Camptothecin (C20H1604N2) in the roots, stems, bark and seeds of Camptotheca camptotheca, matrine (C15H24ON2) and oxymatrine extracted from Sophora flavescens, podophyllotoxin in Podophyllum peltatum, which has good effect on gastric cancer treatment.

2, Berberine from Phellodendron, Fatty oils extracted from seeds of coix lachryma-jobi l, Gypenosides from Gynostemma Extract, which are effective for the treatment of Cervical cancer.

3, Garlic contains diallyl sulfide (DAS), diallyl disulfide (DADS) and diallyl trisulfide (DATS), which can prevent cancer and inhibit tumor cell proliferation.

4, Cherimoya contains bullatacin, which shows strong anti-tumor activity in vivo and in vitro.

5, Guava fruit Extract has the effect of preventing cancer cell spread.

Although the active ingredients in these natural plants have complex names, they can be classified into several categories according to their composition: alkaloids, flavonoids, volatile oils, polysaccharides, organic acids, glycosides and so on.