Natural Substance Fights Tumour in Mice

Photo: Scientists with test tube

In the laboratory, the scientists
tested the potency of several
substances; © Meister/

The basis for this result was an observation made by the scientist Nisar Malek: he had been studying the role of a certain protein - a so-called cyclin-kinase inhibitor - in the development of cancer. In the process, Malek noted that mice in which the breakdown of the kinase inhibitor was suppressed by genetic change have a significantly lower risk of suffering from intestinal cancer. "I needed a substance that would prevent the breakdown of the protein that I was investigating in the cancer cells," says Malek.

With his considerations, Malek approached a chemist, with whom he tested large numbers of different chemical substances. They also tested a collection of natural substances which had originally been isolated from microorganisms which live in soil – the so called Myxobacteria. The myxobacterial agent argyrin possessed the attributes needed.

With this knowledge, the scientists launched a research programme to discover how argyrin can be produced chemically and how it functions. In the process they stumbled upon a completely new mechanism. "Argyrin blocks the molecular machinery of the cell which breakdowns proteins that are no longer required," explains Malek, "and thereby naturally also prevents the breakdown of the kinase inhibitor in question, the lack of which triggers cancer."

The research team has already conducted detailed studies of the effects of argyrin on mice: "When we treat animals with cancer with argyrin," says Nisar Malek, "the tumour ceases growing, it decreases by up to 50 percent and it begins to breakdown internally." Scarcely any side effects have been noted in the animal model.; Source: Helmholtz-Zentrum für Infektionsforschung