The Q&A: Xiang Zhang

With each issue, Trib+Health brings you an interview with experts on issues related to health care. Here is this week’s subject:

Dr. Xiang Zhang is associate professor of molecular and cellular biology at the Lester and Sue Smith Breast Center at Baylor College of Medicine. He recently led research on a study that developed a new lab technique to test the effectiveness of treatments for breast cancer metastases in bones. 

Editor’s note: This interview has been edited for length and clarity.

Trib+Health: Can you expand on the study you led that developed a new lab technique to rapidly test the effectiveness of treatments for breast cancer metastases in bones?  

Xiang Zhang: Most preliminary clinical studies these days use primary tumors as models. In the clinic, what we’re already trying to cure are metastases, which kill around 90 percent of breast cancer patients. There hasn’t been a great model, though. We are trying to put the cancer cells into the bone environment, and we actually invented a platform to have many specimens at once so we can perform multiple parallels to pass the efficacy of different drugs. We are hoping to accelerate the pre-clinical studies looking for effective drugs to treat cancer-related bone metastases.

So what we recently published is basically the methodology of how to perform such experiments using mice as a model. We found that the approach is actually pretty effective, because it allows us to very quickly check over 100 drugs — most of which are already FDA-approved to treat other diseases.

We tested over 100 drugs and found a couple that exhibited extraordinary efficacies when they are in the bone microenvironment specifically, but they are not as effective — or they have different efficacies — with the cancer cell by themselves. But these drugs become more effective in the bone microenvironment. That raised the possibility that we could try these drugs in a clinic to treat patients with high risk of bone metastases or are already diagnosed with bone metastases.

Trib+Health: What were some of the more unexpected aspects of the study?

Zhang: There is also some surprise because some of the newly developed drugs that are currently in clinical trials and are supposed to act against cancer actually promote cancer in our model. That was very unexpected, and we are looking into the mechanisms, but that really alarmed us to use caution when we try new drugs because they can sometimes have unexpected or adverse effects. And that really raised the question to us that we’re going to need to test these drugs with the right model before we go to clinical trials.

Trib+Health: What are the next steps in your research following this study?

Zhang: We are looking into the molecular reasons behind this unexpected efficacy. Our surprise finding doesn’t necessarily mean those drugs cannot or should not be used, it just means we don’t understand the entire system and need to go deeper. We already have some clues why that is the case, but this involves very complicated molecular mechanisms. That actually leads us to other discoveries, which are in process.

For the drugs that work extraordinarily well, we are also looking into the possibility to use them in the clinic as quickly as possible to make some clinical impact.

Trib+Health: Do you have a projected timeline for when those drugs may be used in a clinic for trials?

Zhang: I can’t give you an exact timeline because I need to collaborate with the clinicians first. But I’m very active in the discussion with my clinical colleagues here. Some of them are very excited about this, and we’re hoping we can move this forward as quickly as we can. The bright side is, as I said, some of these drugs are already FDA approved, or they’re in an advanced stage of the clinical pipeline for other diseases.

Trib+Health: Is there anything you’d like to add to today’s conversation? 

Zhang: I would like to emphasize the importance of combining basic research with clinical studies. Right now, there’s a significant gap between them. Clinicians and scientists need to work together. Scientists need to understand the real clinical need from patients, but clinicians also need to collaborate more closely to understand the basic mechanisms and design clinical trials in a more informed manner. I hope our study will further the collaboration between the two sides.