Dan Theodorescu, MD, PhD, with international mentee and collaborator, Tahlita Zuiverloon, MD, PhD

People who travel to Denver from sea level often need a couple days to adjust to the altitude. Imagine what it was like for Tahlita Zuiverloon, MD, PhD, who arrived last May from below sea level. Zuiverloon is a urologist and bladder cancer researcher at Erasmus University Medical Center in Rotterdam, The Netherlands. Though the city itself sits at an average of exactly zero elevation, the lowest point in the Netherlands, 22.2 feet below sea level, is just east of the city. It’s worth it, though, Zuiverloon says – for the next 18 months, she will work in the lab of CU Cancer Center Director, Dan Theodorescu, MD, PhD, to discover genes that predict patient responses to bladder cancer treatments, while seeing firsthand the mechanics of scientific research that will help her further develop her own line of research once she returns home.

“We had known each other through the research community,” Zuiverloon says of Theodorescu. “When the bladder cancer center at my home university was named an academic center of excellence, international collaborations became a priority and due to his reputation as a scientist and as a mentor, Dr. Theodorescu was an obvious choice.”

Zuiverloon helped Theodorescu visit Erasmus as a lecturer for the university’s bladder cancer day, and during that time the two decided to apply together for an international postdoctoral fellowship program that could bring Zuiverloon to Denver for more focused collaboration. Of 38 applicants, eight were invited to give presentations to the fellowship award committee, which chose four researchers for the awards.

Tahlita Zuiverloon, MD, PhD

Tahlita Zuiverloon, MD, PhD

“The sun is always shining here. In the Netherlands, the sun hardly shines,” Zuiverloon says, noting that while she likes to look at the mountains, the CU Cancer Center campus in Aurora is high enough for her.

While she is here, Zuiverloon continues to supervise ongoing work in the Netherlands. For example, one of her PhD students explores genes that predict response to specific bladder cancer treatments. Together they have applied for a research grant to extent the current research project. If accepted, he will join Zuiverloon a year from now for a four-month computational biology internship in the lab of CU Cancer Center investigator James Costello, PhD. Concurrently, Zuiverloon’s own work in the Theodorescu lab seeks to improve these treatments for bladder cancer.

One strategy used to treat early-stage, high-risk bladder cancer is called Bacillus Calmette-Guérin therapy, or BCG. This treatment washes the bladder with a solution containing tuberculosis bacteria, which activates immune cells that happen to also target bladder cancer cells. BCG allows patients with early disease to avoid surgical removal of the bladder, and may be used later in treatment as a maintenance therapy to guard against cancer recurrence. However, some patients fail to respond to BCG. Zuiverloon’s work in the Theodorescu lab hopes to understand why, while also discovering novel therapies.

“What I’m really interested in is to determine which genetic aberrations contribute to patients not responding to BCG treatment and chemotherapy. Knowing how bladder cancers evade therapy could help us target these mechanisms in ways that could increase the effectiveness of these treatments,” Zuiverloon says.

Dan Theodorescu, MD, PhD

Dan Theodorescu, MD, PhD

The Theodorescu lab provides the research infrastructure to ask, and possibly answer, some of these questions.

“This is some hardcore science happening here,” she says.

“Tahlita is an extraordinarily motivated researcher,” Theodorescu says. “Already since her arrival in May, she has contributed to the lab’s output. I’m very optimistic about her work here for the next year and half, and am excited to continue mentoring and collaborating with her even after she returns home. I hope this opportunity helps Tahlita transition from an early-career investigator to become the head of her own research laboratory in the Netherlands.”

This and other international collaborations help spread CU Cancer Center’s expertise in scientific research, while leveraging international intellectual capital to ask important questions here on campus. The result is progress against cancer that benefits everyone impacted by the disease.