• 5/9/2007
  • Hong Kong
  • staff
  • msnbc.com

Scientists in Hong Kong and Australia will soon test an experimental treatment for nose and throat cancer — which “trains” the patient’s own white blood cells to fight the disease.

The trial will begin over the next three months and blood samples will be collected from 30 nasopharyngeal (nose) cancer patients in Hong Kong, said lead researcher Daniel Chua, associate professor of clinical oncology at the University of Hong Kong.

These will be flown to the Queensland Institute of Medical Research, where scientists will isolate and “train” a certain class of white blood cells, or T-cells, to fight the disease.

The battle-ready T-cells will then be cultured and the whole army of cells will be re-injected back into the cancer patients.

Some classes of T-cells have “memory.” Once these T-cells have been exposed to certain invaders and fought them off, they should hopefully launch the same response when they are re-introduced back into the patient’s body.

“(We expect) the T-cells (to) initiate a very aggressive inflammatory reaction and during the process, not only will the T-cells attack the cancer cells, but other immune cells in the body will be called in to eradicate the cancer cells,” Chua told Reuters this week.

Nasopharyngeal cancer, most prevalent in south China, kills one in every three victims and is thought to be linked to diets rich in preserved foods, like salted fish.

Its link to the common Epstein-Barr virus (EBV), from the herpes family of viruses, is well established.

Trained for battle
EBV particles are located inside nasopharyngeal, and T-cells can be trained to recognize EBVs, induce an immune response and kill the cancer cells in the process, Chua said.

The team identified two proteins on EBV particles — LMP1, LMP2 — which T-cells seem to recognize as targets for attack.

“There are different components in virus particles and some are better targets than others; i.e. they can be easily attacked by T-cells if they can be recognized,” Chua said.

“Tumor cells contain the virus particles and when you train the T-cells to attack the virus particles, they actually attack the cancer cells,” Chua explained.

“We will produce the T-cells in large amounts. They should reproduce inside the body and continue to regenerate in the future, so that if the Tumor comes back, they can fight it.”

If the technique works, it could be tried on other cancers with well-established links to viruses, for example, liver cancer, which is linked to hepatitis B virus, Chua said.