ABSTRACT
Paclitaxel is a plant-derived diterpene amide approved for the treatment of ovarian and breast cancer that also shows clinical activity against lung, head, and neck neoplasms; paclitaxel is now one of the best anticancer drugs to come from a plant source. The efficacy of paclitaxel in combination with other drugs and radiotherapy for treating various forms of cancer is just beginning to be exploited, and prospects are promising. The biosynthesis of paclitaxel has been partly investigated by feeding various radiolabeled precursors to Taxus cuttings, ground needles, cell-free homogenates, or bark segments incubated in buffer. Plant tissue culture methods offer a potential alternate source of paclitaxel and related taxoids; taxoids such as 10-deacetylbaccatin can be used in the semisynthesis of paclitaxel and Taxotere. Cell cultures are easily renewable and yield relatively homogeneous, readily manipulated systems for biosynthetic studies on taxoids, with potential for large-scale commercial production.
