Iron is a ‘Double-edged Sword’ For Cancer Cells

A grant by the American Cancer society will be used to investigate the treatment of certain neuroblastoma by forcing them to overloading on iron.

Neuroblastoma is a cancer that forms in nerve tissue, and most commonly in the glands around the kidneys. It is the most frequently occurring childhood cancer that occurs outside the cranium. MYCN is overexpressed in 20-25% of neuroblastoma, and these cancers contribute to a considerable portion of paediatric cancer-related deaths. Recent research has shown that the MYCN gene introduces a weakness to ferroptosis-inducing drugs because MYCN draws on a lot of iron to help the cancer grow.  

“Iron is a double-edged sword in a cancer cell. It can help the cancer grow and survive, but it also creates these toxic molecules within the cell called reactive oxygen species,” explained Anthony Faber, PhD.

Reactive oxygen species (ROS) are unstable molecules that react with other molecules, causing DNA damage and cell death. This recently discovered form of cell death, largely influenced by iron accumulation, is called ferroptosis. Little is known about ferroptosis, and even less about cancers which may be vulnerable to ferroptosis-inducing drugs. By boosting cellular toxin removal systems, MYCN produces so much iron that it also creates a vulnerability to drugs which prevent cells from eliminating ROS. Blocking these toxin removal systems causes death among MYCN-amplified cells. 

“As MYCN continues to be one of the most important targets in cancer therapeutics, this study highlights a new and clinically important strategy for treating MYCN-associated cancers,” Dr Faber said.

“Fortunately, the Cancer Mouse Models Core run by Jennifer Koblinski, PhD, and Bin Hu, PhD, at Massey is spectacular and will allow us to robustly test these FDA-approved drugs in both patient-derived models and orthotopic models, where the tumors grow atop the adrenal glands similar to the way they grow in patients,” Dr Faber said.

If these models show positive results for the testing of these drugs, they can move on to clinical trials. He added that this study may have far reaching implications, as in certain small cell lung cancers and triple negative breast cancer, whose growth is driven c-MYC, a similar protein .

Source: Medical Xpress

Journal information: Konstantinos V. Floros et al, MYCN-amplified neuroblastoma is addicted to iron and vulnerable to inhibition of the system Xc-/glutathione axis, Cancer Research (2021). DOI: 10.1158/0008-5472.CAN-20-1641