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overexpressing multidrug-resistant uterine sarcoma cell line. The non-sulphamoylated compounds were only cytotoxic at micromolar ranges, if at all. The sulphamoylated compounds inhibited pure tubulin polymerization in a dose-dependent manner and induced microtubule destruction in cells after 24-h exposure. Conclusion Results revealed that the novel sulphamoylated 2ME derivatives have potential as anti-cancer drugs, possibly even against chemoresistant cancer cells. These compounds disrupt the intracellular microtubule integrity which leads to mitotic block of the cells.

Sutherlandia frutescens is a well-known South African herbal remedy traditionally used for stomach problems, internal cancers, diabetes, various inflammatory conditions and recently to improve the overall health in cancer and HIV/AIDS patients. The influence of crude Sutherlandia frutescens extracts (prepared with 70% ethanol) was investigated on cell numbers, morphology, and gene expression profiles in a MCF-7 human breast adenocarcinoma cell line. Time-dependent (24, 34, 48 and 72 h) and dose-dependent (0.5-2.5 mg/ml) studies were conducted utilizing spectrophotometrical analysis with crystal violet as DNA stain. A statistically significant decrease to 50% of malignant cell numbers was observed after 24 h of exposure to 1.5 mg/ml Sutherlandia frutescens extract when compared to vehicle-treated controls. Morphological characteristics of apoptosis including cytoplasmic shrinking, membrane blebbing and apoptotic bodies were observed after 24 h of exposure. A preliminary global gene expression profile was o op pe en nU UP P ( (J Ju un ne e 2 20 00 07 7) ) obtained by means of microarray analysis and revealed valuable information about the molecular mechanisms and signal transduction associated with 70% ethanolic Sutherlandia frutescens extracts.

Honeybush tea, a sweet tasting caffeine-free tea that is indigenous to South Africa, is rich in bioactive compounds that may have beneficial health effects. Bone remodeling is a physiological process that involves the synthesis of bone matrix by osteoblasts and resorption of bone by osteoclasts. When resorption exceeds formation, bone remodeling can be disrupted resulting in bone diseases such as osteoporosis. Osteoclasts are multinucleated cells derived from hematopoietic precursors of monocytic lineage. These precursors fuse and differentiate into mature osteoclasts in the presence of receptor activator of NF-kB ligand (RANKL), produced by osteoblasts. In this study, the in vitro effects of an aqueous extract of fermented honeybush tea were examined on osteoclast formation and bone resorption in RAW264.7 murine macrophages. We found that commercial honeybush tea extract inhibited osteoclast formation and TRAP activity which was accompanied by reduced bone resorption and disruption of characteristic cytoskeletal elements of mature osteoclasts without cytotoxicity. Furthermore, honeybush tea extract decreased expression of key osteoclast specific genes, matrix metalloproteinase-9 (MMP-9), tartrate resistant acid phosphatase (TRAP) and cathepsin K. This study demonstrates for the first time that honeybush tea may have potential anti-osteoclastogenic effects and therefore should be further explored for its beneficial effects on bone.