Malfunction and malformation of blood vessels are associated with a broad range of medical conditions, including cancer, cardiovascular diseases, and neurological disorders. The ultimate goal of the Komatsu lab is to find a way to reverse the process of abnormal vessel formation and restore normal function to these vessels. In cancer, normalization of tumor blood vessels facilitates lymphocyte infiltration, potentiating anti-tumor immunity, and enhances the efficacy of immunotherapies as well as conventional cancer treatments. Normalization of regenerating blood vessels is also necessary for reestablishing blood flow to ischemic hearts and limbs, and preventing blindness caused by diabetic retinopathy or macular degeneration. Komatsu lab’s research is uncovering key molecular pathways important for the normalization of pathological vasculature.

The main research goals of my laboratory are: (1) to identify and study the biology of novel cancer selective targets whose enzymatic function can be exploited for therapeutic and diagnostic purposes; (2) to develop methods to target novel agents for activiation by these cancer selective targets while avoiding or minimizing systemic toxicity; (3) to develop novel agents for imaging cancer sites at earliest stages. To accomplish these objectives the lab has originally focused on the development of prodrugs or protoxins that are inactive when given systemically via the blood and only become activated by tumor or tissue specific proteases present within sites of tumor. Using this approach, we are developing therapies targeted for activation by the serine proteases prostate-specific antigen (PSA), human glandular kallikrein 2 (hK2) and fibroblast activation protein (FAP) as well as the membrane carboxypeptidase prostate-specific membrane antigen (PSMA). One such approach developed in the lab consists of a potent bacterial protoxin that we have reengineered to be selectively activated by PSA within the Prostate. This PSA-activated toxin is currently being tested clinically as treatment for men with recurrent prostate cancer following radiation therapy. In a related approach, a novel peptide-cytotoxin prodrug candidate that is activated by PSMA has been identified and is this prodrug candidate is now entering early phase clinical development. In addition, we have also identified a series of potent inhibitors of PSA that are now under study as drug targeting and imaging agents to be used in the treatment and detection of prostate cancer.