Genetically altered mouse resistant to cancer

Researchers at the University of Kentucky have created a genetically altered, or 'transgenic' mouse seemingly resistant to cancer, according to a study published in the journal Cancer Research this month.

The work follows the discovery of the Par-4 gene by UK Professor of radiation medicine Vivek Rangnekar and a team of researchers in the early 1990s. They found that the gene has the ability to induce apoptosis - programmed cell suicide - in cancer cells, but, crucially not in normal cells. The discovery of molecules which selectively target cancer cells are the 'holy grail' of cancer treatment research. Par4 appears to induce death in wide range of cancer cells.

In the new research, the gene was implanted into mouse egg cells. The Par-4 gene is active in all tissues of the resultant pups, and is also switched on throughout their offspring. Despite choosing a strain of mice particularly vulnerable to certain types of cancer, no signs of the disease were identified in the transgenic mice versus a control 'normal' group - in which, after 18 months, 15 of 33 control animals had developed liver cancer and 18 of 33 had cancer of the spleen. Furthermore, the transgenic mice appeared to live on average a couple of months longer than those lacking the protein made by the Par-4 gene.

Current methods of cancer treatment involve surgery, chemotherapy and radiotherapy. These treatments are molecularly quite crude, not distinguishing between healthy and malignant cells, leading to the debilitating side-effects associated with the cancer treatment, which include pain, nausea and hair loss. The Par-4 research offers the opportunity to destroy cancer cells without any damage to normal cells caught in the chemical crossfire.

'We are thinking of this in a holistic approach that not only would get rid of the tumor, but also not harm the organism as a whole', Rangnekar said. A spokesperson for Cancer Research UK stressed that the research was a long way from human trials: 'It's important to remember that this work has only been done using genetically engineered mice, and more research is needed before we'll know if it can be translated to humans'.