Treatment with extracts of Uncaria tomentosa promotes apoptosis in the human breast cancer cell line, MCF7.

Abstract

Uncaria tomentosa is a medicinal plant native to Peru which has been used traditionally for the treatment of various inflammatory disorders and cancer. Some studies have shown that treatment with Uncaria tomentosa promotes repair of cellular DNA in patients treated with chemotherapy drugs, preventing mutations and cell damage. Treatment with Uncaria tomentosa also inhibits inflammatory responses by inhibiting the proliferation of T and B-lymphocytes and decreasing the production of pro-inflammatory cytokines (IL-1, IL-6, and TNF-α). We have examined the effects of Uncaria tomentosa extracts on the growth of malignant cells such as MCF-7 and MDA-MB-231 cells, human breast cancer cell lines and non-malignant cells such as HBL-100, HEK 293T and HSG cells. Our results have shown that treatment of malignant cells and non-malignant cells with Uncaria tomentosa extracts inhibits their proliferation and promotes cell death in a dose-dependent manner. Further, extracts produced by boiling the ground bark in 70% ethanol are much more effective than extracts produced by boiling in water. Uncaria tomentosa-ethanol extracts potently induce cellular apoptosis as measured by changes in cell morphology, chromatin condensation (Acridine Orange/Ethidium Bromide staining assay) and DNA fragmentation (TUNEL assays) within 24 h of treatment. Overall, Uncaria tomentosa appeared to kill breast cancer cells effectively in vitro by increasing cellular apoptosis.