New Lab Model of Meso may lead to better understanding of disease

Saturday, November 26, 2005

Since it is unethical to experiment on people with completely random drugs just to see what happens, scientists rely on laboratory models of disease, sometimes this is an animal model like a mouse and sometimes it is a bunch of cells in a petri dish. This outside the body model of a disease is called an in vitro system.

There can be problems with using in vitro systems. What you observe in a test tube may not translate to what happens in a human body. For example, there are many chemicals that have anti-cancer effects when cancer cells in a test tube are exposed to them. When the same chemical is used in a person it might be toxic, it might break down before it can have an effect, or it may do something completely unexpectected.

In mesothelioma, the current in vitro models have not translated well into actual clinical practice. Compounds that have an anti-cancer effect in the test tube, don't work in the body. Many of these systems are simply cells taken from a tumor and grown in a single layer on some surface like glass.

A new study describing a new mesothelioma model was recently published. Instead of a single layer of cells, the cultured cells were formed into small spheres, that more accurately mimic the multiple layers of a mesothelioma tumor. Experiments indicated that these "spheroids" responded to drugs in a similar way to actual tumors in the body (in vivo).

The benefit of this model is that these spheroids can be grown and used as a testbed for new drugs before they go to human trials. This saves both time and money by avoiding drugs that might have worked in the old models, yet are ineffective in patients. This type of basic research lays the foundation upon which the cures of the future can be built.