MIT Chemists Are Using Anthrax to Deliver Cancer Drugs

The researchers have turned a deadly protein into a carrier for antibody drugs.

Researchers are finding novel ways to use some of the world’s deadliest toxins for other purposes. Botox, for example, is being used to do more than just smooth out wrinkles. New uses include: helping overacting bladderstreating depression; and halting excessive sweating. Now, there’s a new toxin in town: Anthrax.

That’s right, anthrax.

We rendered anthrax toxin so that it’s not toxic. We hijacked it to deliver powerful cancer drugs into cells.

A team of MIT researchers are using a disarmed version of anthrax to administer cancer drugs. “Anthrax toxin is a professional at delivering large enzymes into cells,” says Bradley Pentelute, the Pfizer-Laubauch Career Development assistant professor of chemistry at MIT. “We wondered if we could render anthrax toxin nontoxic, and use it as a platform to deliver antibody drugs into cells.”

And that’s just what they did.

In a new paper published in the journal ChemBioChem, Pentelute and his team showed that they could not only disarm the anthrax toxin, but use it to deliver two proteins that can kill cancer cells. Pentelute, the senior author of the paper, says that this is the first demonstration of effective delivery of antibody mimics into cells, which could allow researchers to develop new drugs for cancer and many other diseases.

“The beauty of Botox is that it can get inside the cell,” Pentelute says. “We’ve taken tools from nature and engineered it so that it can target cancer cells. People have been thinking about using toxins therapeutically for decades. What we’ve been doing for the past three years is figuring out how you can deliver molecules into cells. Nature has devised a way to do this through evolution. We are taking the anthrax toxin and modifying it to use it as powerful therapeutic.”

But, Pentelute says that crossing the cell membrane is really challenging. “One of the major bottlenecks in biotechnology is that there really doesn’t exist a universal technology to deliver antibodies into cells,” he says.

Pentelute says that the ultimate goal is to use this technology on hard-to-treat cancers such as brain and prostate cancers. Currently, the team is testing this approach to treat tumors in mice and working on ways to deliver the antibodies to specific types of cells.

Still, Pentelute says that this is the next generation of modern therapeutics. “Nature is already producing it, and we are taking control of it and using it as a warhead to target cancer,” he says. “The reason why this is next generation is because the molecules can be designed to be highly potent and highly selective. You want it to be selective so that you can kill cancer cells with precision delivery without harming the healthy cells.”