Scientists in the UK have discovered a unique way of killing cancer cells that may lead to new treatments and possible prevention of certain types of cancer.
Prof Jo Milner and Dr Ming Jiang of the Department of Biology at the University of York, announced in the journal, Oncogene that they had used a technique called small interfering RNA (siRNA) to target and kill cervical cancer cells grown in the lab without harming healthy cells.
"Our work has identified a novel agent with major therapeutic potential for the treatment, and possibly also the prevention, of human cervical cancer," said Prof Milner. Cervical cancer is the third most common cause of death of women from cancer in the world and is the leading cause of cancer death for women in many economically underdeveloped nations.
The new research, funded by Yorkshire Cancer Research, looked at human cervical cells that were infected with human papillomavirus (HPV), the main cause of cervical cancer, said Milner. Cervical cancer develops when the virus attacks the cells and overrides the body's natural defence against cancer.
The viral action stops two proteins called p53 and RB from working. Normally, p53 would kill the cell if it became damaged and RB would control cell division, however in cells infected with HPV, the virus stops these two proteins from functioning, and the cells are free to multiply to form a tumour.
However, when cancerous cells infected with HPV are treated with siRNA, they all die. This is because the siRNA stops the rouge virus genes from giving instructions to the rest of the cell, Prof Milner explained. "As soon as we silenced these viral genes, the infected cancer cells committed suicide," she said. By stopping the virus from controlling the cell, the normal defence processes recovered and the damaged infected cells killed themselves.
The siRNA technique was particularly exciting because it had no effect on the normal growth and behaviour of healthy cells, she said. "The beauty of the system is that we are just targeting the virus," she told The Irish Times. She described the elimination of cancer cells without harming normal cells as "absolutely remarkable".
Milner added that more tests would need to be carried out "to completely verify that there was no adverse effect on other normal human cells".
"The phenomena of RNA interference techniques are a very exciting thing," stated Dr John Atkins, head of biotechnology for Science Foundation Ireland. It is understood that clinical trials using siRNA to treat people with cervical cancer could take place within three to five years.