Fumou Sun, PhD, Assistant Professor, Hematology and Oncology, recently joined the MCW Cancer Center as a research member aligned with the Discovery and Developmental Therapeutics program. Dr. Sun earned his PhD from China Pharmaceutical University and brings extensive expertise in tumor genetics and immunotherapy, gained through years of impactful research at the University of Iowa, MCW, and most recently, the University of Arkansas for Medical Sciences.
Dr. Sun’s research focuses on advancing Chimeric Antigen Receptor (CAR) T-cell therapies to improve outcomes for patients with relapsed and refractory tumors. His work aims to enhance the therapeutic efficacy of CAR-T cells while tackling key challenges such as resistance and safety concerns. In collaboration with Froedtert & MCW’s exceptional clinical team, Dr. Sun is dedicated to translating these therapies into clinical trials, bridging the gap between innovative laboratory research and transformative patient care.
“Creating new CAR-T cells is akin to sculpting a masterpiece—meticulously engineering T cells to display unique and powerful anti-tumor capabilities. The opportunity to harness both knowledge and creativity to enhance these cells with groundbreaking functionalities is not only profoundly rewarding but also a testament to the transformative potential of this work,” said Dr. Sun.
Get to Know Dr. Sun
Tell us about some of your current projects.
I am currently developing a cutting-edge dual-targeted CAR-T therapy for multiple myeloma (MM). This innovative therapy features a unique “switch” mechanism, enabling precise targeting of both widespread normal myeloma cells and highly drug-resistant variants, with enhanced accuracy and safety. Additionally, I am advancing armored CAR-T cells designed not only to eradicate myeloma cells but also to repair the damaged microenvironment caused by bone lesions in MM. Beyond these efforts, I am pioneering novel CAR-T designs to expand their application to solid tumors, tackling the critical challenge of achieving effective tumor infiltration in these complex cases.
What sparked your interest in CAR-T therapy research; what unresolved questions do you hope to explore?
My journey into CAR-T research feels like a series of fortunate milestones that have shaped my career. During my PhD, I focused on antibody engineering, which gave me a deep understanding of single-chain variable fragments (scFvs)—a vital component of CAR-T cells for tumor recognition. This foundational expertise set the stage for my future work in the field. During my postdoctoral training at MCW, under the mentorship of Dr. Siegfried Janz, I explored the pathogenesis and immunology of MM. Witnessing the extraordinary therapeutic responses of CAR-T therapy in MM was a pivotal moment that ignited my passion for this innovative approach. MCW’s state-of-the-art Cell Therapy Shared Resource further fueled my curiosity and solidified my commitment to advancing this promising therapy.
Convinced of CAR-T’s potential as a powerful tool in revolutionizing cancer treatment, I delved deeper into the field, including specialized training at a company focused on CAR-T commercialization to understand the intricacies of the production process. This hands-on experience allowed me to design and construct novel CAR-T cells, expanding the boundaries of what this therapy can achieve. Although CAR-T therapy received approval from the U.S. Food and Drug Administration only seven years ago, the field continues to face significant challenges. By drawing on my multidisciplinary expertise, I’m dedicated to overcoming these obstacles and contributing to the evolution of this transformative therapy to improve outcomes for cancer patients.
How is CAR-T therapy impacting future research and, ultimately, patients?
CAR-T therapy, known for its exceptional safety and efficacy, is emerging as a transformative force in cancer treatment. With hundreds of CAR-T therapies in clinical trials, the field is advancing rapidly, driven by groundbreaking innovations poised to expand its reach and effectiveness. Researchers are developing next-generation CAR constructs with enhanced targeting specificity, greater persistence, and reduced toxicity, integrating features such as multi-specific targeting, immune checkpoint modulation, and “armored” CARs designed to resist the immuno-suppressive tumor environment.
Significant efforts also focus on extending CAR-T therapy to solid tumors, tackling challenges like antigen heterogeneity and the hostile tumor microenvironment. Innovative designs, including dual-targeting CARs and strategies to improve tumor infiltration, are at the forefront of this work. Additionally, in vivo CAR-T approaches, which modify immune cells directly within the body rather than through ex vivo processes, are being explored to broaden access and open the door to new indications, including autoimmune diseases. These advancements represent a profound leap forward, addressing current limitations and offering transformative possibilities for patients with cancer and other complex diseases.
When it comes to multiple myeloma, what’s the biggest challenge?
Anti-BCMA CAR-T therapies have demonstrated remarkable potential, achieving high response rates in patients with MM. For example, single-agent BCMA-CAR-T therapies like cilta-cel have demonstrated reduced the risks of disease progression or death compared to standard care while delivering superior overall and complete response rates.
Despite these successes, challenges remain. The responses, though initially impressive, are often short-lived, with a growing number of patients experiencing relapse after anti-BCMA CAR-T therapy. My research is dedicated to addressing these limitations by understanding the mechanisms of relapse and developing strategies to enhance the durability of CAR-T responses, ultimately aiming to improve long-term outcomes for patients with MM.
What do you love most about what you do?
I take immense pride in advancing CAR-T therapy, finding deep fulfillment in designing novel, multifunctional CAR-T cells to tackle critical clinical challenges. For me, creating new CAR-T cells is akin to sculpting a masterpiece—meticulously engineering T cells to display unique and powerful anti-tumor capabilities. The opportunity to harness both knowledge and creativity to enhance these cells with groundbreaking functionalities is not only profoundly rewarding but also a testament to the transformative potential of this work.
Learn more about Dr. Sun’s and view his full list of research publications.