From influencing immunotherapy responses to causing life-threatening infections, microbes pose a significant yet underappreciated threat to cancer patients. Fyza Shaikh, a cancer researcher at Johns Hopkins School of Medicine, uses her broad research background and clinical experiences to understand the processes underlying these threats and advocate for better treatment options.

     Image of Fyza Shakih
Fyza Shakih explores the myriad ways microbes affect cancer patients.
Fyza Shaikh

How do you study the role of microbes during cancer treatment? 

The gut microbiome influences the response of many tumor types to checkpoint inhibitors. I analyze patient samples to determine what microbes and metabolites facilitate this response. I also put those microbes into mice to understand the pathways affecting the immune cells.

How do antimicrobial resistant microbes come to infect cancer patients?

Patients who have their immune systems diminished by cancer treatments often present with infections initially related to gut bacteria. Neutrophils form a barrier in the gut lining, and if a patient lacks these cells, bacteria can translocate from the colon to the bloodstream, causing an infection. We prescribe a broad-spectrum antibiotic to such immunocompromised patients. At some point, they may encounter a bacterium that is resistant to that antibiotic, and we hope that there is a backup antibiotic available. If we cannot treat a patient who has a nonfunctional immune system, it puts us in a tough place.

What is the solution to this problem?

There are very few antibiotics in the development pipeline, so there needs to be more investment in research and development. This is difficult because it is not the most lucrative area; physicians hope to use antibiotics rarely and as a last line of defense. We also need to explore other treatments such as phage therapy, small molecule inhibitors, chemistry modification of existing therapeutics, or different combinations of current drugs. Also, it is important to have good public health surveillance and containment strategies within the high-risk healthcare environment to stop infection spread.

This interview has been condensed and edited for clarity.