Amit Singh is a postdoctoral fellow at the National Cancer Institute where he investigates how host–microbiome interactions and innate immune pathways influence the tumor microenvironment to identify novel biomarkers for cancer therapy. In this Postdoc Portrait interview, he shares how his work bridges the gap between basic microbial research and translational oncology.
Probing the Microbiome and Innate Immunity
Q | What drew you to studying cancer biology and host-microbiome interactions?
My interest in science began early, sparked by curiosity about how things work. I had a fascination with nature's hidden mechanisms. As a child, I would spend hours conducting small experiments at home mixing household chemicals, observing insects, or taking apart gadgets to see what was inside. This hands-on exploration fueled a love for discovery and a desire to understand biological mysteries.
In college, a transformative biology class introduced me to the complexity of the immune system and the dynamic relationship between humans and the microbial world. The idea that microscopic organisms can shape health and disease captivated me. I was especially drawn to cancer biology and host-microbiome interactions, realizing how vital it is to uncover these microscopic connections to improve therapies and prevention strategies. Over time, every lab project and breakthrough, no matter how small, deepened my commitment to research, and transformed my curiosity into a focused passion for advancing science and human health.
Enhancing Cancer Immunotherapy Outcomes
Q | What excites you most about your current research project?
One of my favorite research projects investigates how the gut microbiome influences anti-tumor immunity and cancer progression through modulation of innate immune receptors such as Toll-like receptors (TLRs). In this study, we integrate metagenomic sequencing, immunophenotyping, and tumor transcriptomics with advanced 3D skin organoid models to dissect host-microbe-tumor interactions in a physiologically relevant context. These 3D skin organoids recreate the complex architecture, stratification, and cellular diversity of human skin, enabling us to model microbial exposure and immune signaling with high fidelity. This system allows us to observe how microbiota-driven TLR4 signaling affects immune cell recruitment, cytokine profiles, and tumor progression. So far, our findings revealed distinct microbiota compositions linked to specific immune activation patterns in the tumor microenvironment. By combining 3D organoid systems with preclinical mouse models and patient-derived samples, we aim to translate these insights into microbiome-based biomarkers and therapeutic strategies that could enhance cancer immunotherapy outcomes. This project excites me because it merges my expertise in cancer biology, immunology, and microbiome research, while leveraging cutting-edge organoid technology for translational impact.
Q | What is a rewarding aspect of your research?
The most exciting part of my scientific journey has been the opportunity to integrate multidisciplinary approaches to address complex biological questions. During my postdoctoral work at the National Cancer Institute, I combined microbiome research, cancer immunology, and advanced 3D skin organoid models to investigate how host–microbe interactions influence tumor progression.
Developing and applying these organoid systems was a turning point for me—they provided a physiologically relevant, human-based model that bridged the gap between in vitro studies and in vivo observations. Using this platform, I could visualize how specific microbial signals modulate innate immune pathways, influence immune cell infiltration, and alter tumor growth dynamics. Seeing clear, mechanistic links emerge from datasets that spanned metagenomics, immunophenotyping, and transcriptomics was both intellectually rewarding and deeply motivating. It reinforced my belief that impactful discoveries often come from crossing traditional boundaries, whether between disciplines, technologies, or perspectives. This project not only sharpened my scientific skills but also deepened my commitment to translational research that can ultimately inform novel cancer prevention and treatment strategies.
Q | If you could be a laboratory instrument, which one would you be and why?
I’d choose to be a microscope, preferably a high-resolution, confocal microscope. A microscope is central to scientific discovery: it reveals hidden worlds, bridges the gap between what we see and what truly exists, and empowers researchers to explore the unknown. I admire how a microscope allows scientists to focus on the finest details cells, proteins, even bacteria leading to insights that can transform medicine and biology. The microscope is both a tool for curiosity and a catalyst for breakthroughs; it encourages patience, precision, and a sense of wonder. Much like a microscope, I’d love to help magnify the important questions, bring clarity to complexity, and inspire those around me to see familiar things in brand-new ways.
Responses have been edited for length and clarity.
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