Prostate cancer is resistant to most forms of chemotherapy and is notoriously difficult to treat, but British researchers have found a new way to make the disease succumb more readily to currently used treatments.
The key, according to the researchers, is blocking the action of a gene called IGF1R, resulting in prostate cancer cells becoming more sensitive to radiotherapy and certain kinds of chemotherapy.
The researchers believe the technique could improve survival prospects for patients with prostate cancer that has become resistant to treatment.
Previous studies have shown that IGF1R might be a good target for cancer treatment. The researchers wanted to see if inactivating the gene could improve the impact of existing treatments on prostate cancer.
Using a new technology called RNA interference (RNAi) to block IGF1R, the researchers found that switching off IGF1R in a selection of prostate cancer cells resistant to different treatments made the cells two times more sensitive to radiotherapy.
The technique made the cells significantly more sensitive to chemotherapy drugs that kill cells by damaging their DNA. In contrast, the technique did not enhance the effect of chemotherapy drugs that kill without causing DNA damage.
"These results suggest that IGF1R plays a role in the cell's response to DNA damage, and will tell doctors which type of chemotherapy drugs are likely to be enhanced by treatments targeting the gene, " said researcher Dr. Val Macaulay, of Cancer Research UK.
"This is the first study to show that silencing the IGF1R gene can improve the effectiveness of treatments for prostate cancer. As an oncologist I am excited at the possibility of conducting trials of IGF1R-inhibiting drugs with my own patients," added Macauley.
Noting that cancer cells have broken free of natural controls over their ability to divide, Robert Souhami, of Cancer Research UK, said many researchers are looking at ways to bring cancer cells back under control and to stop them dividing and spreading around the body.
"IGF1R sustains many types of cancer cell, so blocking the gene could prove a powerful new way of treating tumors,” said Souhami. This is early stage research, but holds great promise in the fight against not only prostate cancer but other forms of the disease."
