Graduate Student Poster Competition: National ADSA Dairy Foods Poster

Angiogenesis, the development of new blood vessels from pre-existing vascularization, represents one of cancer’s hallmarks. Blood supply is essential for a tumor to progress toward a malignant condition since this allows the delivery of nutrients and oxygen necessary to support cancerous cells’ growth as well as entrance into the circulation causing metastasis to arise. Study on angiogenesis inhibitors has shown promising results on animal models. Blocking cancerous cells’ blood access resulted in a reduction on primary tumor size and number of metastatic colonies. One of the peptides that showed interesting results on this study was angiostatin, the internal fragment of the fibrinolytic enzyme plasminogen in blood. It is well known that bovine plasminogen gets transferred into milk during lactation. The objective of this research was to investigate enzymes capable of releasing the antiangiogenic peptide from bovine plasminogen and compare the anticancer activity of the fragment with that of human angiostatin. We tested enzymes such as Lactobacillus (L. casei, L. reuteri, L. acidophilus) and Bacillus (B. subtilis, B. cereus, B. coagulans) originated proteases, Bacillus polymyxa metalloprotease dispase as well as elastase. Techniques such as SDS-PAGE, column chromatography, MALDI-TOF, and Western blot were utilized. After hydrolysis, results from electrophoresis showed bands in the molecular range of 37 kDa, which were confirmed through sequence analysis to belong to the kringle 1–4 region of plasminogen. Test for anticancer activity on melanoma and colon malignant cells, demonstrated a reduced proliferation of cancerous cells for samples treated with angiostatin and plasminogen; interestingly highest inhibition was obtained for treatments from bovine sources. We believe that these results represent a starting point for future development of novel dairy products capable of cancer prevention.