Plant extracted protein inhibits tumor growth and migration
The plant in question is known as monkey's ear and has been studied since the 1980s
Professor at the Federal University of São Paulo (Unifesp), Maria Luiza Vilela Oliva, and other researchers at the institution found, in the seeds of the tree known as monkey's ear, a protein with the capacity to inhibit at least five types of cancer: breast , prostate, melanoma (skin cancer), colorectal and leukemia.
The protein from the unusual tree was named as Enterolobium contortisiliquum trypsin inhibitor (EcTI). “We called EcTI trypsin inhibitor because this was the model enzyme that we started to study, as it is cheaper. But it is patented as an inhibitor of several proteases. We also patent its action against cancer,” said Maria Luiza.
The protein was isolated for the first time in the professor's doctoral research, in the late 1980s. The antitumor function was only discovered in the early 2000s and patented four years later.
“We were looking for molecules capable of inhibiting the action of proteases – enzymes whose function is to break the peptide bonds of other proteins. These molecules are involved in numerous physiological and pathological processes in the body; an inhibitor could have interesting therapeutic effects”, commented the professor.
How do you act?
The protein has already been used in several tests in vitro in the inhibition of cancers, achieving great results. “Before migrating to other tissues, the tumor cell needs to adhere to the connective tissue that supports it. EcTI blocks proteases present in the extracellular matrix and the signaling pathway used by the tumor in this process without affecting the fibroblasts, which are the healthy cells of this connective tissue”, explained Maria Luiza.
The protein has also shown good results in the cancer treatment process. When associated with 5-Fluoracil chemotherapy, it required a dose 100 times lower than the traditional one, which represents a great reduction in the side effects of the treatment. In addition, an antithrombotic function was found in the protein. Thrombosis is a common illness in people undergoing chemotherapy.
“This protein inhibits the action of kallikrein, an enzyme that triggers the blood clotting process and also activates platelet aggregation. The effect was verified both in a model of arterial thrombosis, in rats, and of venous thrombosis, in mice”, said the researcher.
Other studies, carried out at FMUSP (Faculty of Medicine, University of São Paulo), evaluated the action of EcTI on pulmonary inflammation and found encouraging results. In other research, good prospects were also revealed regarding its action on Chagas disease.
Research must continue at full steam. Tests have not yet shown any allergic reaction in mice, however, researchers warn of the unpredictability of the protein's reaction in humans.
