Imaging Residual Brain Tumor Cells to Improve Glioblastoma Treatment

What biomedical issue did you address in your research and what did your studies find?

My Ph.D. research addressed glioblastoma, the most common primary brain tumor in adults. Typically, a biopsy of a glioblastoma taken during surgery is sufficient to make a diagnosis but may not reveal the complexity of the cancer; various sections of the same tumor can differ in their molecular makeup and vulnerability to treatment. Importantly, residual tumor that exists after surgery is difficult to see in MRI images as cancerous cells can invade beyond the main mass and hide throughout the brain.

My thesis project aimed to characterize the complexity of a glioblastoma tumor and to determine a means to identify residual cancer using MRI. Taking samples from several locations within each tumor, I analyzed the genetic code and advanced MRI imaging features of each sample. Our study showed that some imaging features in an MRI correlate to certain genetic features of invasive brain tumor cells. Our findings, published in Nature Communications, showed that advanced MRI imaging can be used to correlate with aggressive features of hiding populations of cancerous cells.

I also investigated a protein called STAT5, a transcription factor that turns "on" certain genes. Dr. Tran's lab had previously identified that STAT5 is particularly active in cancerous cells that exist outside of the main tumor. My studies found that a drug that targets STAT5 can slow cancer cells — when the tumor cells harbor a certain genetic alteration, known as EGFRvIII. To date, clinical trials of the drug have not specifically focused on whether a patient has the mutation. Thus, inhibiting STAT5 may be a strategy to investigate in the future using an approach more individualized to each patient's tumor profile.

What aspects of Mayo's culture helped you grow as a scientist and as a thinker?

I'm graduating as an M.D.-Ph.D. student from Mayo's Medical Scientist Training Program. A special aspect of attending medical and graduate school at Mayo Clinic is that everyone I worked with and learned from manifested Mayo's central tenet: The needs of the patient come first. I saw this in my clinical training and even in scientists working in laboratories who never see patients but keep this ethic at the forefront of their minds.

One of my favorite opportunities was participating on the Neuro-Oncology Molecular Tumor Board at Mayo Clinic in Arizona. To assist the neuro-oncology practice, I prepared and presented individual patient cases to a multidisciplinary group that included neuro-oncologists, radiation oncologists, oncology pharmacists, and scientists. The meetings involved discussion about all the data available, from clinical trials to basic cell biology principles, and helped guide patients' treatment. The experience provided excellent education about the importance of bridging clinicians and scientists to help shape patient care.

What's next?

I have matched into a physician-scientist residency training program in internal medicine with the goal of specializing through fellowship training in solid tumor oncology. In addition to treating patients who have cancer, I aim to oversee a laboratory that studies cancer genetics.