New Zealand researchers have found a way to stop the growth of certain cancer tumors by " silencing" a group of PAX genes, members of a small family of genes that play important roles in embryonic development, but also allow cancer cells to grow and divide in adult tissue.
In an article published in UK medical journal Oncogene, Otago University Professor Michael Eccles and colleagues revealed how they used the PAX8 gene to kill cancer cells.
After detecting high levels of PAX8 protein in the majority of kidney, ovarian and thyroid cancers they studied, the researchers used molecular techniques to silence the PAX8 gene in several cancer cell lines.
"We found that these PAX8-depleted cancer cells ceased growing and dividing. The cells were essentially stopped in their tracks through the failure of multiple mechanisms and pathways crucial to their cell division cycle. They then entered into a state called senescence in which they no longer divided, and after that they ultimately died," Eccles said in a statement from the university Tuesday.
The findings suggested that PAX8 could be a good target for the development of new cancer therapies, he said.
"Any resulting drugs would be a long way down the road, but in the meantime this research helps confirm that a focus on PAX genes may prove to be a fruitful line of attack against a number of cancers," he said.
The research was supported by grants from the Health Research Council of New Zealand. It formed the main piece of work carried out by Otago doctoral graduate Caiyun (Grace) Li, now a postdoctoral fellow at Stanford University. Study co-authors also included Professor Antony Braithwaite and master's student Jen Nyman.
In 2003, research led by Eccles discovered that proteins from one or more of the nine PAX genes were present in many common cancers. They found that "silencing" the gene expression of PAX2 in ovarian and bladder cancer cells, and of PAX3 in melanoma, led to the rapid death of the cells.