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Can a probiotic help dogs with bladder cancer? | Probiome Clinical Trial

Updated: Mar 14

Prof Vanessa Hale from Ohio State University is leading a new trial to investigate how probiotics might improve cancer treatment outcomes.

There is a strong link between gut microbiome and cancer treatment outcomes, according to many research studies involving cancer patients.

For example, in one of our webinars, Prof Natalia Shulzhenko MD PhD, from the Oregon State University reviewed recent findings about how some human patients who were not responding to immunotherapy became responders with the help of alteration to the gut microbiome. (Prof. Shulzhenko is now leading an investigation to help more canine patients respond to immunotherapy) 

In this new canine cancer study led by a team at Ohio State University, researchers are investigating how adding probiotics might improve clinical outcomes for canine bladder cancer patients when a special type of probiotics is paired with a standard-of-care therapy (vinblastine/piroxicam).

(Bladder cancer is also known as urothelial carcinoma (UC) or transitional cell carcinoma (TCC).)

The trial is called The Probiome Clinical Trial and is recruiting patients at three different sites: the Ohio State University, University of Georgia, and NC State University. 

We interviewed Prof Vanessa Hale, a professor from Ohio State University Veterinary College of Medicine who is leading the study.

Here’s the transcript of the interview.

You can also watch the video on YouTube.

(By the way, this study is not funded by CCA.  We are helping raise awareness about this important study)

What is being tested in the clinical trial?

Prof Hale:

What the treatment involves and what we're actually testing in this trial is the addition of a probiotic to a standard of care therapy for urothelial carcinoma, also known as transitional cell carcinoma (TCC), which is bladder cancer in dogs. 

The probiotic is called E. Coli Nissle 1917. 

People are adding probiotics to cancer therapy [in human medicine] and they're not only seeing improvements in side effects, but they're also seeing things like tumor reduction or prolonged progression-free survival, which is really incredible. So, we really want to see if it can improve cancer care in these dogs and that's the goal of this trial. 

We are collecting gut microbiome samples and urine microbiome samples from these dogs. The treatment regimen is eight weeks long so these dogs get chemotherapy every two weeks. They have their blood counts measured every week just to make sure to assess their white blood cells and make sure they're not getting too low. We're partnering with the clients to collect feces and urine and bring that to us. 

What are the benefits of joining the clinical trial?

The benefits for the client, whether you're on a placebo or whether you're on probiotics, you're getting the standard of care therapy for your dog with bladder cancer (paid for by the study). Another benefit to this is maybe we'll learn about how something like a probiotic could be used to supplement cancer care and cancer therapy and improve outcomes. 

This trial is heavily subsidized, so if an owner of a dog who has bladder cancer and that dog qualifies for this trial, this would be a very minimal cost to the owners.

Why is E.coli-based probiotic being studied?

We chose this probiotic (E Coli Nissle 1917)  for a couple of reasons. 

One, we have clinicians here at Ohio State University who have tested it in healthy dogs and kind of looked at it over time to see if dogs tolerate it well. So we knew that that was going to be a good option. 

E. coli is responsible for a lot of urinary tract infections. It's one of the number one. bacteria that cause urinary tract infections in dogs and in humans. 

Dogs with bladder cancer often get urinary tract infections. 

The gut is thought to be a reservoir for the E. coli that can cause a urinary tract infection. So, these bacteria find their way from the gut to the bladder and then they can potentially cause infection there, but there are specific types of E. coli that can do that.

If we can give a (beneficial) E. coli to the gut and replace potentially some of these other (harmful) E. coli that are there that are infection causing, maybe we can actually reduce something like urinary tract signs. 

What are the requirements to be eligible to join the trial?

There are no requirements based on breed. We are looking for dogs that don't have a history of significant gastrointestinal or skin disease, so if you've got chronic dermatitis issues or chronic inflammatory bowel disease, we are ruling out those dogs because of the potential impacts on the microbiome and we really want to understand the potential impacts on the microbiome without adding some comorbidities into that that would also influence the microbiome in a different way. 

These dogs cannot have a history of radiation therapy and they cannot be on antibiotics or have a raw diet or a diet with probiotics in the last three weeks. That's only within the last three weeks so if someone wants to enroll but maybe they're currently on a diet with probiotics or antibiotics, then they can cease that particular antibiotic as clinically advised and then enroll three weeks later and that would be fine. 

As long as you are not changing that diet, you have no probiotic supplements and you are not adding any supplements and you are not changing that diet during the course of the trial, we can accept dogs that maybe just have some kibble that is is pre-existing in their diet that does have probiotics in it. 

Are there risks associated with probiotics?

There are always small risks associated with probiotics or potential gastrointestinal distress. Just like, if we go into the supermarket and buy a probiotic, it could cause some gastrointestinal distress. We think the risk of that is very low based on what we've seen in dogs so far and based on the dogs that have already enrolled in the trial that have done very well.

Anything else?

All in all, E. coli NIssel 1917 had a good combination of safety, tolerability, and then the potential to improve clinical signs.

The other thing that's kind of cool about it is E. coli can target tumors so it can localize to tumor tissues and what we're really intrigued to test in this is if this probiotic, will be able to localize to the tumor tissue and then ramp up a positive immune response. 

They're negative or inflammatory immune responses that are protumorigenic so they can cause the tumor to grow but there's also an opposite kind of immune response where you can ramp up certain immune reactions that actually inhibit the growth of the tumor or promote immune cells that help clear the tumor.

That's something that we have much less data on or evidence for, but we know E. coli can localize to tumors and so that's something we're really excited to test and see if we can improve tumor outcomes.

If you think your dog might be eligible or know someone whose dog might have bladder cancer, visit here for pre-screening:


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Questions? Email us at info@ccralliance and we'll get back to you as soon as we can!

Canine Cancer Alliance is a volunteer-led nonprofit. We support research for prevention and cure of canine cancer.

Coco's Story: Three years ago, Coco was diagnosed with bone cancer and her family was told that she only had 3 months to live. Watch her amazing journey, shared by Coco's mom.

All information provided by the Canine Cancer Alliance website is for informational purposes only. It is not intended to be a substitute for professional veterinary advice.

Always seek guidance from your veterinarian with any questions regarding your pet’s health and medical condition.

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