Bioactive Peptides as Therapeutic Adjuvants for Cancer.

Conventional cancer treatments such as chemotherapy, radiotherapy and surgery cause serious side effects on cancer patients which decrease their quality of life. In the past few years, cancer patients have been interested in the use of complementary medicine to improve the efficacy of conventional cancer treatments and decrease the side effects. Among the broad spectrum of complementary medicine, bioactive peptides from natural sources have gained great interest due to their potential use in the treatment of chronical diseases such as cancer. This review reports an updated survey of bioactive peptides, from natural sources, with anticancer and immunomodulatory activities obtained by enzymatic hydrolysis. Several peptides have demonstrated anticancer effects on and essays, such as: selective cytotoxicity, inhibition of growth, tumor size reduction and immunomodulation. However, there is absence of formal pharmacokinetic profiles and standardized extraction procedures of bioactive peptides. Further clinical trials are necessary to verify these anticancer effects and, facilitate the use of peptides in the treatment of cancer.