Gregory A. Durm, MD, a hematology/oncology fellow at the Indiana University School of Medicine, is helping to break new ground in the fight against cancer by studying circulating tumor cells (CTCs) in lung cancer.

CTCs are cells that have broken away from primary tumors and have entered into the bloodstream. CTCs that survive the bloodstream’s assault could migrate to distant parts of the body where they can become the seeds of metastatic disease. Technologies to detect CTCs have improved in recent years, in part through collaborative multi-institutional efforts such as a parallel flow micro-aperture chip system developed and tested by Purdue University engineers and investigators at the IU Simon Cancer Center.

Better detection of CTCs may result in improved patient care, says Dr. Durm. “Rather than having to biopsy places that are hard to get to and putting patients through invasive procedures, being able to isolate the cells from the circulation means that we could potentially learn about their tumor from a simple blood draw.”

Dr. Durm’s research combines CTC detection technology with analysis of programmed death-ligand 1 (PD-L1) expression on CTCs. An overexpression of PD-L1 on the surface of cells can prevent the immune system from recognizing and attacking cancer cells. A new class of drugs, known as PD-1 (programmed death-1) and PD-L1 inhibitors, blocks the link between PD-L1 and the PD-1 receptor. By inhibiting this connection, these new drugs allow the immune system to carry out its normal function, and thereby help the body fight cancer. Recent studies have shown these inhibitors have induced durable responses in a variety of cancers, and new studies — including HCRN’s LUN14-179, on which Dr. Durm is serving as co-investigator — are exploring the potential for these drugs to treat even more cancers.

But what could a study involving CTC detection and PD-L1 expression mean for patients?

According to Dr. Durm, if investigators are able to detect PD-L1 expression on the surface of CTCs, “then we can potentially look at people’s cells just by simple blood draws and be able to tell whether or not they are going to respond to these [PD-1 and PD-L1] therapies. As far as we know, this is something that has never been looked at before.”

Dr. Durm notes that the numerous studies involving PD-1 and PD-L1 inhibitors are just one part of the larger exploration of immune therapies to treat cancer, what CBS news anchor Scott Pelley described as the “fourth weapon” in the fight against cancer in a recent 60 Minutes episode — the other weapons being surgery, radiation, and chemotherapy.

But even the best weapons are useless without those who can expertly wield them. Key to this process is collaboration between colleagues and mentorship that occurs between junior and senior investigators. Dr. Durm credits a number of mentors at the IU Simon Cancer Center who have helped guide his professional development. They include Drs. Nasser Hanna, Larry Einhorn, Shadia Jalal, and Safi Shahda, among others.

As a fellow at the IU School of Medicine, Dr. Durm spends much of his time at Indiana University hospitals, but he also consults at other hospitals, including the Richard L. Roudebush VA Medical Center in Indianapolis.

“I was a chief resident at the VA, and I really enjoyed taking care of the veterans,” said Dr. Durm. “I’d like to continue to have a role there in some capacity, enrolling veterans in studies or teaching fellows who are taking care of veterans.”

Hoosier Cancer Research Network recently honored Dr. Durm as recipient of the 2014 George and Sarah Jane Fisher Young Investigator Award. This award will help further his research on CTCs and PD-L1 expression.

The $15,000 award, established in 2011 by William B. Fisher, MD, and others through the George and Sarah Jane Fisher Fund, is given annually to an Indiana University oncology fellow or faculty member who has made significant contributions to clinical or basic science research in collaboration with the Hoosier Cancer Research Network. Dr. Fisher established the George and Sarah Jane Fisher Fund in the mid 1990s in memory of his mother, Sarah Jane, and brother, George, both of whom died of cancer within the span of three years. Dr. Fisher is a co-founder of Hoosier Cancer Research Network and served as the organization’s vice chair until 2000.

“I was very surprised to be selected for this award,” said Dr. Durm. “When I look back and see who has been selected in previous years — people who I look up to a lot and who have a lot of success and great talent — to follow in their footsteps is really quite an honor.”

There is no shortage of questions yet to be answered in cancer research, notes Dr. Durm. The challenge is acquiring the funds necessary to conduct studies.

“Sometimes, it’s just a matter of finding enough funding to get the trials going to answer very important questions,” he said. “That’s why the Fisher Award is so important, because it helps fund some of that research, and helps that research go forward.”

A graduate of Notre Dame and the Indiana University School of Medicine, Dr. Durm completed his internal medicine residency at Indiana University, where he served as chief fellow. He is currently in the second year of his fellowship at the IU School of Medicine.

About Hoosier Cancer Research Network:

Hoosier Cancer Research Network (formerly known as Hoosier Oncology Group) conducts innovative cancer research in collaboration with academic and community physicians and scientists across the United States. The organization provides comprehensive clinical trial management and support, from conception through publication. Created in 1984 as a program of the Walther Cancer Institute, Hoosier Cancer Research Network became an independent nonprofit clinical research organization in 2007. Since its founding, Hoosier Cancer Research Network has initiated more than 150 trials in a variety of cancer types and supportive care, resulting in more than 300 publications. More than 4,600 subjects have participated in Hoosier Cancer Research Network clinical trials.