A Revolutionary Cancer Treatment Device Inspired by the Mosquito
Fiber-optic microneedle will deliver chemotherapy drugs—or more-cutting-edge nanoparticles
This segment is part of the IEEE Spectrum series “The New Medicine”
Susan Hassler: A team of engineers at Virginia Tech is developing a novel tool that could revolutionize the treatment of some cancers. It’s called a fiber-optic microneedle device, or FMD. It’s designed to deliver state-of-the-art treatments directly into a tumor. And it’s modeled on a creature you’re more likely to swat than celebrate. Mia Lobel has more.
Mia Lobel: When most people hear the tiny, high-pitched whine of a mosquito, they think of the fastest way to get rid of it. Virginia Tech mechanical engineer Christopher Rylander thinks of something entirely different.
Christopher Rylander: We know the mosquito can land on the human skin and insert their needle, their microneedle, several millimeters deep into skin. So we knew that the insertion of a very small-diameter needle was feasible based on nature’s example.
Mia Lobel: Rylander and his team were able to design a fiber-optic needle the same size and shape as a mosquito’s stinger. We’re talking about 40 microns here—less than the width of a human hair. And very sharp.
Christopher Rylander: So it can easily be inserted into the tissue with minimal surrounding tissue damage.
Mia Lobel: Less tissue damage, and potentially less pain, and quicker recovery times. But what’s unique about Rylander’s device is that it can do two things at once. It can inject fluids directly into a tumor—delivering things like conventional chemotherapy drugs or more-cutting-edge nanoparticles. It can also deliver light from powerful lasers. Two cancer-fighting treatments combined into one medical device to find and destroy unwanted tissue. This fiber-optic microneedle device—or FMD—is the basis for a whole series of experimental technologies that may one day change the way doctors treat cancer patients.
Christopher Rylander: So, collectively, what do we call this team, John?
John Robertson: The thing we call the team is Team Onco and the Cancer Engineers.
Mia Lobel: Dr. John Robertson is the director of the Center for Comparative Oncology at Virginia Tech’s vet school.
John Robertson: Everybody calls me Dr. Bob.
Mia Lobel: He’s a cancer survivor himself.
John Robertson: You can probably see the scar just under my ear here. So both my wife and I have—have dealt with neoplastic disease in the last couple of years. And boy, I really hate cancer.
Mia Lobel: Dr. Bob and his wife are both doing well now, but he knows that’s not the case for many cancer patients. He’s says the FMD could potentially go a long way toward treating some of the most aggressive cancers.
John Robertson: By the time that we see the more advanced forms of both bladder tumors and brain tumors in people, we’re past the point really where we’re going to do much to help them. The morbidity, mortality over the few years, three, four, five years, the amount of suffering, the things that happen to patients are just horrific... This device and the folks that are working with it and the things that we can do with it, the broad applications, are going to allow us to get at those advanced cases and offer these patients...some hope, some new ideas.
Mia Lobel: Common cancer therapies like chemo and radiation have a number of drawbacks. Chemotherapy is delivered directly into the bloodstream and is known for its devastating side effects. Plus, many chemotherapeutic drugs can’t cross the blood-brain barrier, making them ineffective in treating brain cancer. Radiation, at its best, is imprecise, and can create new cancers even as it treats existing ones. The Virginia Tech team works with lesser-known optical therapy treatments—using light to destroy cancerous tissue up close.
Christopher Rylander: Okay, now we’re walking down the hallway... I’ll swipe my access card, and it lets us into the laboratories.
Mia Lobel: Christopher Rylander shows me around the laboratory. It’s packed with optical equipment and a handful of grad students.
Christopher Rylander: You can see another student’s coming in about 11, 11 o’clock... They usually stay here hard at work until about 2 or 3 in the morning, and then they sleep it off and come in about 11 or maybe noon, just in time for lunch. Look, he’s blushing.
Mia Lobel: Off to the side of the main lab is a smaller room that houses some of the more sensitive equipment.
Christopher Rylander: So now we’re entering a room that has a few more optical components.
Mia Lobel: Two of Rylander’s grad students demonstrate the power of light to destroy tissue. A piece of pigskin smokes and crackles beneath the powerful beam.
Christopher Rylander: So many people think that lasers are very precise. But due to the phenomena of scattering of light and tissue, where the light is delivered actually becomes very blurry because the light does not stay confined to the region right at the point of delivery. The light will scatter out, analogous to how automobile headlights scatter in a foggy night.
Mia Lobel: The FMD is designed to control this scattering by delivering both light and light-absorbing nanoparticles at the same time. The nanoparticles are injected into the tumor, and the light is absorbed exactly where it needs to be.
Christopher Rylander: Okay. Now we’re heading out of our lab... We’re heading to my wife’s office, Nichole Rylander. She—she’s a collaborator on several of these projects, and her expertise is in nanomaterials and their use in treating cancer... Here she is.
Marissa Nichole Rylander: Hi. Hi, I’m Nichole Rylander. Nice to meet you.
Mia Lobel: Marissa Nichole Rylander is the director of the Tissue Engineering Nanotechnology and Cancer Research Lab. She and Christopher Rylander have been married since 2001.
Marissa Nichole Rylander: We met in freshman orientation, undergraduate freshman orientation at UT Austin in 2000—I’m sorry, in 1996. We were studying mechanical engineering at the time, but we both had significant interest in potentially pursuing medical school. But we just saw the huge reservoir of understanding in terms of engineering that we could apply to these biomedical problems that we found really exciting.
Mia Lobel: The couple has been working on the FMD project together since 2007.
Marissa Nichole Rylander: So we’re now entering the lab. So, I’m going to take you over to one of the graduates that are working on this project.
Kristen Zimmerman: My name’s Kristen Zimmerman... And I’m working on conjugating fluorescent nanoparticles to the surface of the carbon nanohorns.
Mia Lobel: Carbon nanohorns are flower-shaped nanoparticles with a relatively huge surface area. This is ideal for absorbing laser light and for transporting drugs to the targeted tumor cells.
Marissa Nichole Rylander: These particular particles that we look at, they’re on the order of kind of a spherical sort of Koosh ball shape. They’re a size and shape that cells like to bring into them... So it’s great for ferrying of drugs that might not otherwise cross the cell membrane.
Mia Lobel: Carbon nanohorns are also less toxic than other nanomaterials, which takes care of one major hurdle in clinical use of nanotechnology. But one main challenge remains: how to study the behavior of the particles in the highly complicated and unpredictable human body. So what they do is engineer body tissues in the lab to mimic the complex environment of a tumor.
Tobias Ecker: And this device—at this site we are basically trying to simulate the brain tissue.
Mia Lobel: A couple of students are looking at how the fiber-optic microneedle device could deliver nanoparticles in a real-life treatment situation. Grad student Tobias Ecker makes a small adjustment and plunges the FMD into a Jell-O–like substance called a brain phantom. He turns on a pump that slowly pushes blue dye into the synthetic tissue, creating a bloom of color that moves out and around the microneedle.
Tobias Ecker: And then we will take pictures in certain—like, certain time steps. And later on, we can use them at the computer, and we can basically look at different, like, concentrations and how the fluid disperses over time.
Mia Lobel: Brain cancer is one of the main targets for the fiber-optic microneedle device; it’s often one of the hardest cancers to treat.
Christopher Rylander: If you think of the roots on a weed in the grass, when you pull them out, they’re infiltrating into the dirt, and that’s how the brain tumor is in the brain.
Mia Lobel: So you can’t simply cut out the tumor. Using the FMD, surgeons could potentially highlight the cancerous tissue with light-absorbing nanoparticles, then destroy it with pinpoint accuracy.
Christopher Rylander: And we can do so perhaps painlessly, or at least minimally invasively, without creating too much bleeding and healthy tissue damage.
John Robertson: What has evolved here is the discipline of cancer engineering, where there’s been this cross-fertilization between cancer biologists and veterinarians and physicians and just a wonderful team of engineers that are able to bring together disciplines that normally wouldn’t talk to one another under a unifying theme, this cancer-engineering theme.
Mia Lobel: Center for Comparative Oncology director John Robertson says the team at Virginia Tech is unique in the nation, not just for its state-of-the-art technology but also for the interdisciplinary nature of what they do.
John Robertson: You know the nice thing about engineers? Okay. You—you got an idea, you got a problem, and you—you find a—you find a really bright series of engineers, a set of engineers, and they’re all sitting around, and [you] go, “Hey, guys, I need you to build something.” And they do. And then we test it, and then we say, “Well, we’d like it to change a little bit,” and then they change it. And then it gets better and better and better. We’re on a very rapid development path. It doesn’t take us—oh, let’s talk about it for three or four years. Our patients don’t wait three or four years. They die.
Mia Lobel: The team is on a fast track to get the fiber-optic microneedle device into clinical trials. As John Robertson says, cancer doesn’t wait. In Blacksburg, Va., I’m Mia Lobel.
Photo: Roger De Marfa/iStockphoto