10.22376/ijpbs.2019.10.1.p1-12 Volume 7 Issue 2 2016 (April - June) Extracts from the leaves of lessThan i greaterThan Catharanthus roseus lessThan /i greaterThan were collected using methanol. Three individual alkaloids were fruitfully separated by TLC, purified using column chromatography and one of them was successfully identified as vinorelbine. Nude mice xenografted with breast cancer cell line MDAMB231 were treated through vinorelbine (30 mg/kg body weight, i.p.). Mice responded to the treatment and showed a significant decrease in the tumor volume in comparison to mice of the control growth. Results shows that the plant extracted vinorelbine may be helpful for treating the breast cancer. GIREESH KAMATH H, DEECARAMAN AND RAMESH KV Breast cancer, plant extract, nude mice, xenograft, Vinorelbine, tumor volume. 204-211