For the first time, scientists have identified master cells that give birth to deadly skin cancers, a discovery that could pave the way for new treatments for the potentially fatal disease.
Researchers at the Stanford University found the ’master cells’ that are responsible for the growth of malignant melanoma tumours — the sixth common cancer in the U.K. which affects more than 10,000 people every year.
The disease is caused by exposure to ultraviolet light and numbers have quadrupled over the past 30 years as more people enjoy sunshine holidays abroad or use tanning booths, the Daily Mail reported.
Eight out of 10 melanomas are found at the early stage when the condition is easy to treat by removing the tumour.
However, Dr. Alexander Boiko, who led the research at Stanford University, said the newly discovered ‘stem cells’ in advanced skin cancers were often missed by conventional immunotherapy.
“Without wiping out the cells at the root of the cancer, the treatment will fail,” he said.
In recent years, scientists have discovered that a subset of cancer cells lies at the root of many kinds of tumour. These cancer stem cells can make copies of themselves and differentiate into other cancer cell types.
Unlike normal cancer cells, stem cells are resistant to radiotherapy and chemotherapy, allowing cancers to return after treatment.
Cancer stem cells were first identified in blood cancers, but have since been found in tumours of the bladder, brain, breast and colon.
The latest study, published in the journal Nature, is the first time they have been found in malignant melanoma.
“I didn’t know if melanoma would in fact have the cancer-initiating cells,” said Dr. Boiko.
“I was completely unbiased, so I was actually sort of surprised to find such a clear-cut answer. It fits exactly what’s been discovered in the studies of other solid tumours.”
While looking at samples of skin tumours Dr. Boiko discovered a distinctive subset of cancer cells. A marker on the surface of the cell was previously found on stem cells.
When he transplanted these cells to laboratory mice, he found they were much more likely to cause skin cancers than other cells taken from the human tumour.
He also found that the cells self-renewed and turned into different types of cancer cell.
The discovery, the researchers said, would lead to new treatments designed to target cancer stem cells and stop the disease recurring.
Dr. Kat Arney, science information manager at Cancer Research UK said: “Researchers are finding cancer stem cells in many different types of tumour, and many scientists believe they are at the heart of a wide range of cancers.
“Understanding these elusive ‘immortal’ cells will be the key to developing more effective treatments for cancer in the future, so this research is an important step towards beating melanoma