New research indicates that paclitaxel, which is the most commonly used chemotherapy for breast cancer, suppresses tumors when given at a certain dosage, but at low doses, it actually promotes cancer spread to the liver.

The findings suggest that lowering the dose of paclitaxel to reduce toxic side-effects is not a safe strategy.

"Paclitaxel and its analogous compounds are the first line agents widely used in clinical cancer chemotherapy. However, potential risks and reasonable treatment strategies of paclitaxel continue to be widely investigated," wrote the authors of The FEBS Journal study.

Article: Low doses of paclitaxel enhance liver metastasis of breast cancer cells in the mouse model, Qi Li, Zhuang Ma, Yinhua Liu, Xiaoxi Kan, Changjun Wang, Bingnan Su, Yuchen Li, Yingmei Zhang, Pingzhang Wang, Yang Luo, Daxiang Na, Lanlan Wang, Guoying Zhang, Xiaoxin Zhu, Lu Wang, The FEBS Journal, doi: 10.1111/febs.13767, published 16 June 2016.