The present invention offers a solution to the lack of an effective alternative method to those already known to treat angiogenesis. In particular, the present invention is the first to show that a substantially pure population of exosomes derived from MenSCs have capacity to reduce tumor angiogenesis in diseases such as prostate cancer, breast cancer and pancreatic cancer. In this sense, the present invention shows that a substantially pure population of MenSCs-derived exosomes reduce the endogenous levels of reactive oxygen species (ROS) in cancer cells and the expression of pro-angiogenic factors such as VEGF, NF-KB, FGF and HIFα in the treated tumors. Overall, the invention offers a promising alternative method to treat angiogenesis. Since it is principally composed of exosomes produced by the Stem cells present in menstrual fluid, the invention provides an ease access and repeated sampling in a non-invasive manner. Such attributes allow the rapid production of the treatment.