How Radiotherapy Can Be Used In Combination With Drugs

Radiotherapy Centre - doctors looking at the image

Our radiotherapy centre can now treat a very wide array of conditions. The technology of radiotherapy has been developed over the last 120 years to offer hope and extend life to sufferers of various forms of cancer.

This has become more adroit over time, with particular tools like the gamma knife being able to direct the beams more precisely than ever in sensitive areas like the brain.

Whether it is brain, prostate, head, neck, cervix, or eye, radiotherapy has been fine-tuned to deliver better results in each case. However, oncologists will often use radiotherapy in conjunction with other treatments, such as chemotherapy or surgery, to deliver the best possible results.


A New Breakthrough?

This is especially so with chemotherapy. New combinations are being trialled all the time and some provide impressive results that lead to them becoming established practices. The next to do so might be a combination of radiotherapy and a drug called AZT1390, which has been shown in new research to be safe as well as effective.

In results presented to the annual meeting of the American Association for Cancer Research earlier this month, it was revealed that the use of the drug prevents the cancer cells from repairing their DNA in the wake of radiotherapy as effectively as they normally would.

Explaining how the drug supports radiotherapy and the importance of its development, Dr. Jonathan T. Yang of the Memorial Sloan Kettering Cancer Center, who presented the findings, noted that most glioblastoma patients do not live for more than two years beyond diagnosis and progress to date on treatments has been slow.

“Despite efforts to improve survival, the current standard of care continues to be a backbone of radiotherapy with or without temozolomide without much innovation in the past two decades,” he remarked.

Dr Yang added: “This context highlights both the urgent need to develop new medicines and the historical challenges of developing novel therapeutics for this devastating disease.”


How Inhibiting Cancer Cell DNA Recovery Helps Radiotherapy

A key feature of how radiotherapy works is that it kills cancer cells by damaging their DNA, preventing them from reproducing. However, a problem that can occur, including in glioblastomas, is that cancer cells can then activate what is known as the ATM cell signalling pathway, which can repair much of the disrupted strands of DNA.

This mechanism limits the effectiveness of radiotherapy, but AZT1390 acts as an inhibitor, stopping this response and therefore slowing or even halting the pathway, meaning the cells do not repair the DNA and will therefore not be able to reproduce.

A key problem with many drugs is they have not been able to penetrate the blood-brain barrier, preventing them from supporting radiotherapy aimed at shrinking brain tumours. However, AZT1390 has been designed to do this and the latest trials have now provided firm indications that it is a safe drug as well as an effective one.

Studies showed that patients given the drug only had fairly mild, manageable and usually reversible side effects from the treatment, which indicates that using them will not have a major negative impact.

Dr Yang noted that if the early data indicating the significant effectiveness of the drug is backed up by further studies, it could provide a major new weapon in the fight against glioblastomas.

Since around half of all cancer patients receive radiotherapy, any additional or complementary treatments that increase its effectiveness will clearly have a large impact, helping increase survival rates and potentially providing useful data for future research to make further advances.


Other Ways Drugs Can Support Radiotherapy

The use of inhibitors to stop cells from repairing their DNA is just one of the ways drugs can help radiotherapy be more effective. For example, anti-angiogenic drugs can halt the growth of blood vessels in tumours, depriving them of the blood and oxygen they need to grow and thrive. While metabolic inhibitors prevent enzymes from binding, curbing cell growth.

If you have been diagnosed with cancer and need radiotherapy, there are very good reasons that you may not have that treatment alone, but the use of drugs of the kinds mentioned above to help make the treatment more effective.

That means when you come to speak to our oncologists and other experts, the plan for your treatment may have more elements to it than you might have previously imagined. But that is also a reflection of the fact that there are now more weapons in the fight against cancer.

It may be that AZT1390 is soon added to this arsenal after further research. But many drugs already have a role to play and more are sure to come in the years ahead.