By Cristina Chin
You may have come across the acronyms EFGR, ALK, ROS1 and many more—all associated with genetic alterations found in lung cancer tumors. Thanks to their discovery in the past decade, the dawn of personalized medicine was born, bringing with it an array of treatment options for patients with those specific alterations.
But what about small cell lung cancer (SCLC), a highly aggressive type of lung cancer with a slim overall 5-year survival rate of just 6%? Turns out, we are just beginning to uncover the possibilities of personalized medicine for SCLC.
“Small cell lung cancer has been treated as a singular disease for over 40 years until recent discoveries show there are in fact molecular subsets,” Dr. Trudy Oliver from University of Utah explained. Trudy and her lab, funded by a 2018 LCRF pilot grant, are testing a drug called ADI-PEG20 that treats a specific subtype of SCLC. “Back in 2017, we were able to find the presence of a certain genetic alteration called MYC in small cell lung cancer tumors. With our current LCRF grant funding we are testing a treatment for this particular MYC alteration.”
Tumors high in MYC shrink significantly when deprived of arginine, an amino acid found in protein-rich foods such as meats, nuts, and legumes that is naturally synthesized in the body. “When paired with [ADI-PEG20], an enzyme that chews up extracellular arginine, we actually see tumor shrinkage and even tumor death in MYC positive SCLC,” Trudy explained.
The current standard of care for SCLC is chemotherapy. In mouse models, the ADI-PEG20 drug performed remarkably better than over 16 comparable chemotherapy treatments. “And toxicity is not as much of a concern with ADI-PEG20 because arginine is organically made in our own bodies and there are newer studies suggesting it may stimulate the immune system.”
Trudy understands how daunting it can be to see a loved one receive a lung cancer diagnosis. “A few years ago, my mother got a low-dose CT scan that showed a nodule … we didn’t know if it would grow or not, so it was decided to just monitor it. And it really hit home how stressful it can be to not know what your best options are.” Trudy, inspired by her mother’s story, is working hard to change the outcomes for patients living with SCLC.
“Drug resistance and the evolving nature of cancer are a reality, so we need something that’s evolving as well to keep up. Our immune system is designed to evolve, and that needs to be part of the answer. Cancer prevention is so important – imaging technology can help find tumors early, before they’re nasty.”