In recent years, a number of natural products isolated from Chinese herbs have been found to inhibit proliferation, induce apoptosis, suppress angiogenesis, retard metastasis and enhance chemotherapy, exhibiting anti-cancer potential both in vitro and in vivo. This article summarizes recent advances in in vitro and in vivo research on the anti-cancer effects and related mechanisms of some promising natural products. These natural products are also reviewed for their therapeutic potentials, including flavonoids (gambogic acid, curcumin, wogonin and silibinin), alkaloids (berberine), terpenes (artemisinin, β-elemene, oridonin, triptolide, and ursolic acid), quinones (shikonin and emodin) and saponins (ginsenoside Rg₃), which are isolated from Chinese medicinal herbs. In particular, the discovery of the new use of artemisinin derivatives as excellent anti-cancer drugs is also reviewed.

Curcumin, a low-molecular-weight natural polyphenol mainly found in the plantCurcuma longa(turmeric), is widely used as a food colorant and as a potential protective agent against several chronic diseases including cancer, HIV-infection, neurological, cardiovascular, and skin diseases. Moreover, evidences from long-term use process and preclinical trials have demonstrated low toxicity of curcumin, even at relatively high doses. However, it has been well known that the application of curcumin was limited owing to its water insolubility, instability, and poor bioavailability. For decades, many attempts have been made to compensate for these disadvantages, with the development of improved delivery platforms as the feasible approaches. The past ten years witnessed the encouraging progress in the use of nanoscale drug delivery systems on curcumin such as loading curcumin into liposomes or nanoparticles, forming self-microemulsifying drug delivery systems (SMEDDS), cyclodextrin inclusions, and solid dispersions, as well as the latest reported technologies such as nadodisks and nanotubes. This paper summarizes the recent works on the design and development of nanoscale delivery systems of curcumin, with the goal of harnessing the true difficulties of this multifunctional agent in the clinical arena.