Research Spotlight: A Unique Long-Term Research Method Helping Unlock Cancer’s Origins

Q: How would you summarize your study for a lay audience?

All of us have preneoplasia, that is, abnormal changes in cells and tissues that aren’t yet cancerous, but could lead to cancer over time. We all carry these so-called “cancer seeds” in our bodies for decades, with some of these seeds remaining benign or others eventually progressing to cancer.

While most cancer research focuses on people after they’ve been diagnosed, we wanted to understand what happens in the body long beforethat — in other words, how these seeds "grow" in patients. To explore this, our group has been making use of a powerful, but often overlooked, research approach called the prospective cohort incident-tumor biobank method (PCIBM).

This approach helps us connect everyday behaviors over decades with the biological changes that lead to cancer, filling a critical gap in our understanding of cancer development over time.

Q: What questions were you investigating?

We wanted to understand why some people develop cancer over time while others don’t, even though everyone is born with cancer seeds. We asked ourselves, what causes this difference?

Research suggests that long-term lifestyle choices play a major role, with estimates showing that maybe half of cancer cases could be prevented through healthy habits. Using PCIBM, we explored how cancer seeds grow over decades and how they eventually show up in tumor tissue.

Q: What methods or approach did you use?

PCIBM uses the backbone of long-term studies that follow large groups of people. Over the course of these studies, a rich pool of health and lifestyle data is collected — data that illuminates how and why cancer seeds may grow. PCIBM also adds the component of tumor tissue profiling. So when participants of these long-term studies develop cancer, their tumors are collected in a biobank for analysis. This combined approach provides unique evidence into the etiology of cancer.

For example, this paper highlights our early PCIBM-based study which found that people who took aspirin regularly over time had a lower incidence of developing a specific type of colorectal cancer. Even now, 18 years later, there’s been no other study in humans (to our knowledge) that has been able to replicate this finding — showcasing just how unique the insights from PCIBM-based studies can be.

Q: What did you find?

Our many PCIBM-based studies have allowed us to discover a wide range of novel and unique associations between long-term exposures and tumor development, including specific characteristics such as microbial and immune biomarkers. Additionally, we found that prolonged consumption of Western-style diets was linked to an increased incidence of a specific type of colorectal cancer.

Q: What are the implications?

While we all carry cancer seeds from birth, the good news is that many cancers can be prevented and we have a long window of opportunity to make a difference. The earlier we adopt healthy habits (as soon as infancy and early childhood), the better our chances of reducing risk. And even if it's later in life, it's never too late to make positive changes.

For those undergoing cancer treatment, a healthy lifestyle can support better outcomes. For those who are currently cancer-free, it's important to understand that cancer seeds grow over time, so making healthier choices now can still have a big impact.

Q: What are the next steps?

Despite the potential of the PCIBM, very few studies use this approach — likely less than 1 in 10,000 tumor tissue profiling studies worldwide. We hope to continue raising public awareness and support for PCIBM-based research, because it holds an incredible promise for understanding and preventing cancer. To advance this mission globally, we plan to establish a collaborative initiative aimed at expanding our research efforts.