Study of Toxins’ Impact on Brain Motivated by Social Justice

Ph.D. student Destiny Tiburcio and mentor Dr. Michal Toborek
Destiny Tiburcio and Dr. Michal Toborek (photo by Emre Dikici, Ph.D.)
Article Summary
  • Destiny Tiburcio, a Ph.D. student, and Michal Toborek, M.D., Ph.D., received the HHMI Gilliam Fellowship to study phthalates and brain cancer.
  • The fellowship places a considerable emphasis on diversity, equity and inclusion, values reflected by the work of Tiburcio and Dr. Toborek.
  • Tiburcio believes phthalates pose the greatest risk to people who live near Superfund sites, a disproportionate number of whom are people of color and economically underprivileged.

Can an environmental toxin cause brain cancer?

Destiny Tiburcio, a University of Miami Miller School of Medicine Ph.D. student, is using support from an HHMI Gilliam Fellowship to study the effects of phthalates on the blood-brain barrier and the brain’s defenses against cancer cells.

Tiburcio and mentor Michal Toborek, M.D., Ph.D., the Leonard M. Miller professor of biochemistry and molecular biology at the Miller School, were among the 50 graduate student-thesis adviser pairs chosen for fellowships that promote diversity, equity and inclusion. The fellowship provides awardees $53,000 per year and can be extended for up to three years.

Early Curiosity Fuels Scientific Passion

Tiburcio’s inquisitiveness surfaced at an early age. By age 3, her favorite word was “Why?” She often called her mother at work to deploy it. So often, in fact, mom had to impose a three-question limit during office hours.

“Choose them wisely,” she told the young Tiburcio.  

Studying phthalates within the realm of cancer biology with Dr. Toborek, a Sylvester Comprehensive Cancer Center researcher and vice chair for research for the Department of Biochemistry and Molecular Biology at the Miller School, is the current expression of Tiburcio’s curiosity.  

“Phthalates are ubiquitous environmental toxicants found in food packaging and cosmetics,” said Tiburcio. “They’re endocrine-disrupting chemicals and persistent organic pollutants. My hypothesis is that phthalates can induce a disruption in circadian rhythms.”

Toxins and the Body’s Natural Processes

Tiburcio is investigating the impact of phthalates on the natural processes that tell the body when it’s time to do things like eat and sleep. Her discoveries could provide important details about the impact of waste disposal, particularly for people of color, who are more likely to live in areas where toxins are dumped.

Man sitting in bed cannot sleep from insomnia
Ph.D. student Destiny Tiburcio is investigating the impact of phthalates on natural processes like sleep.

“Policymakers need to know how to make better decisions and consumers need to know about sleeping habits and lifestyle changes,” she said.

The HHMI Gilliam Fellowship’s emphasis on diversity and inclusion dovetailed perfectly with the philosophy that catalyzes Tiburcio’s and Dr. Toborek’s work.

“The purpose of science is to help everyone,” said Tiburcio. “Without including a diverse background in the people who do the medicine and people who receive it, there is no balance. We are not achieving the goal of doing the greater good for all.”

The demographics of the Toborek Lab that hosts their work reflect that diversity.

“At least 75% of students in the lab are from minority or underrepresented groups,” said Dr. Toborek. “We pay attention to DEI (diversity, equity and inclusion) and those values that are being emphasized by the fellowship, and we create this environment in the lab. The department of biochemistry has DEI champions and the leadership of Dr. George has been crucial.”

Health Care Diversity, Equity and Inclusion 

Sylvester molecular geneticist Sophia George, Ph.D., associate professor of gynecological oncology and associate director of diversity, equity and inclusion at the Miller School, co-mentors Tiburcio on the phthalate study.

“Empowering trainees from diverse backgrounds to conduct robust and meaningful science collectively improves our communities. By bridging the gap, we enable these communities to receive appropriate health care interventions so they may thrive as we mentor the next generation of scientists,” said Dr. George.

“We’re talking the talk and walking the walk,” said Tiburcio. “It goes all the way up. Without that support and genuine desire, I wouldn’t have the confidence to apply for a fellowship like this. Having a university that supports you and what you look like is amazing.”

Tiburcio also anticipates her findings could have a ripple effect that extends far beyond the Toborek Lab. In addition to her research, she mentors undergraduate and graduate students. She told one of her mentees, a woman of color who lives near Homestead Air Force Base Superfund site, about her work.

“You saw a lightbulb go on in her head,” Tiburcio said. “She can use this research to work in her own community.” 


Tags: blood-brain barrier, brain cancer, Dr. Michal Toborek, HHMI Gilliam Fellowship, Sylvester Comprehensive Cancer Center