New drug blocks brain cancer advance, making chemo kill easier

Invasive brain tumors are often unstoppable, and even chemotherapy drugs can't always halt their advance. That could change with a new compound called imipramine blue.

Emory University and Georgia Institute of Technology professors found that the drug helped beat back the aggressive tumors in rats (similar to human glioblastomas), slowing the tumors down enough that the doxorubicin chemotherapy treatment could do a better job. After all, a stationary target is easier to hit than a moving one, right? They considered the results successful enough that they'll plan animal studies testing the compound on metastatic tumors, prostate and breast cancers and also additional trials using the drug to hopefully quash invasive brain tumors. Details of their initial work are published in the journal Science Translational Medicine.

"Imipramine blue is … simply stopping the movement of the cancer cells and containing the cancer so that the chemotherapy can do a better job," Ravi Bellamkonda, Ph.D., a lead author and biomedical engineering professor at both schools, said in a statement. He also noted that the "results reveal a new strategy for treating brain cancer that could improve clinical outcomes."

How interesting to create a drug that appears to stop aggressive brain cancer from advancing, slowing those cells down long enough so doctors can inject chemo for the kill. Human trials are years away, however. And as always, drugs can work well in rats but fail in people. But a potentially new drug that can keep brain cancer from advancing and in doing so, boost how well chemotherapy can perform--especially for such a difficult disease--is worth waiting for.

Emory University School of Medicine's Jack Arbiser actually designed the drug, which is technically an organic triphenylmethane dye. They delivered the treatment to the rats inside of a liposome, which allowed it to reach the brain, traveling intact until hitting tumor-influenced leaky blood vessel walls and rupturing. Researchers found that all rats receiving the treatment plus a subsequent liposome filled with doxorubicin survived for 200 days--more than 6 months--without an observable tumor mass. Just 33% of rats receiving only chemo lived 200 days with a 44-day median survival time. Rats treated with just a liposome filled with saline or the imipramine blue, but not chemo, lived no longer than 19 days.

Arbiser, in the research announcement, also explains how he came up with the drug. He chose to formulate it as a triphenylmethane dye because another variation known as gentian violet has been shown to have anti-cancer qualities. And the imipramine, he said, is a long-used depression drug that has been shown to reach the brain.

- here's the release
- read the journal abstract