2. Department of Chemistry, University of Otago, New Zealand.
Curcumin, a spice found in curry powder, is receiving considerable attention as a possible chemopreventative and chemotherapeutic. This review considers the evidence for the use of curcumin as a treatment for breast cancer, particularly triple negative breast cancers (lacking ER, PR and HER2) which are resistant to many current treatments. Evidence suggests that curcumin suppresses the growth of breast cancers both in vitro and in vivo. In ER- cell lines curcumin causes apoptosis via a range of mechanisms at concentrations ranging between 1 µM and 7.6 µM depending on the cell line and system. In xenograft models, curcumin has been shown to be effective but is limited by its bioavailability. This can be improved by nanotechnologies such as micelles. Studies with micelles have shown that these systems increase the uptake and cytotoxicity of curcumin in vitro. In xenotransplantation models micelles improved bioavailability and increased the half-life of curcumin while showing increases in apoptosis in implanted tumours. The last area discussed is the development of curcumin derivatives. Many of these show increased cytotoxicity (less than 1 µM) and improved pharmacokinetic profiles in vivo. The most potent of these compounds developed to date are RL66 and RL71 with IC50 values less than 1 µM across a range of breast cancer cell lines, decreased metastasis in a xenograft model, decreased angiogenesis markers and improved tumour growth inhibition as compared to curcumin. Overall, this review concludes that curcumin and its derivatives show future potential as a powerful broad-spectrum treatment for breast cancer.
Keywords: Curcumin, breast cancer, nanotechnology, micelle, derivatives, chemotherapeutic, triple negative breast cancer