ALS drug shows promise in treating melanoma
Nearly 76,000 people were diagnosed with melanoma in 2014, according to the National Cancer Institute website.
Suzie Chen, a professor in the Ernest Mario School of Pharmacy, uses mouse models to study how melanoma progresses from its initiation to the possibility of metastasis, or the spread of a cancer or disease to another organ not directly connected to the cancer or disease. They then move from mouse models to human cell cultures in an effort to gain knowledge to use for human patients, she said.
While more than 900,000 people were diagnosed with melanoma in the United States by 2011, about 90 percent lived at least 5 years after diagnosis. Chen is helping lead the fight to make melanoma fully survivable and preventable.
“When studying [a] mouse model, we noticed that it has a lot of glutamate,” she said. “Glutamate is an amino acid, and for a long time people knew cancer cells put a lot of glutamate into their surroundings. We also found this in the culture cells.”
The main question about the glutamate, Chen said, was why there was so much extra glutamate in the cells. Since it was found in tumor cells and not normal cells, her team concluded that the glutamate promoted tumor cell growth.
James Goydos, a professor at the Cancer Institute of New Jersey, recommended that Chen test a drug used to treat Amyotrophic Lateral Sclerosis, also known as Lou Gehrig’s disease, she said.
Tumor cells in a culture treated with this drug began to die off, Chen said.
Chen then tested the drug in an animal model.
“A culture cell in the closed system can only have one type of cell growing,” she said. “When testing an animal, you have all the cells and interactions between different cells. You may get a different answer.”
Upon moving to this “in vivo” system, she ended up seeing the same results, she said. After injecting a tumor and subsequently treating the animal with the drug, the progression of tumor growth decreased tremendously.
While the drug slowed down the growth of primary tumors, Chen said tumor metastasis, when the tumor spreads to other organs, was what usually kills patients. The tumor will generally metastasize in the brain, where it can become especially fatal.
“When a patient has a brain metastasis,” she said, “they are not given a long time to live. Surgeons will remove the tumor from your brain, and they will expose the patient to gamma radiation to try and irradiate the tumor cells.”
Taking the results they had gotten from the drug previously, Chen and her team created a brain metastasis animal model. By tagging the tumor cells, she was able to track the development of the tumor without killing the animal.
Chen’s tests split the animal models into four groups that got different treatments: One group had both gamma radiation and the drug, one had only radiation, one had only the drug and the final was treated with nothing.
The tests showed combining the drug with gamma radiation had the highest efficacy in reducing the brain metastasis from growing, she said. The results told Chen’s team that a similar process could work in humans.
Despite the known risk of melanoma and other skin cancers, many people do not take enough measures to protect themselves and their skin, said Melvin Pastrana, a School of Engineering sophomore.
He said he regrets not wearing sunscreen whenever he gets sunburned.
“I’ve been lucky enough to avoid melanoma for the short longevity of my life,” he said. “I can’t say much about the future. I should probably take more caution, but I’m not really inclined to remember to care.”
Krupa Parikh, a School of Arts and Sciences senior, said she is not intensely worried about melanoma. Students who take the necessary precautions, such as applying sunscreen, should be fine.
Tiffany Kingsley, a School of Engineering junior, said people should worry more about their body and skin. Having had a precancerous birthmark removed, she is interested in a drug that can treat melanoma.
“There could be a bump that could be nothing, but it could also be something big,” she said.
Chen said the next step is to attempt to try it in humans to see if it will actually help people. Since the drug is already FDA approved, she said, they can quickly move into clinics without having to wait through the approval process, which take up to 20 years.