'Future of battle with cancer': Toxic stem cells to fight tumors

A team of Harvard scientists has successfully developed special stem cells that produce toxins which kill cancerous cells, causing no harm whatsoever to healthy ones.

“Now, we have toxin-resistant stem cells that can make and release cancer-killing drugs,” Khalid Shah, a co-author of the study and the director of the Molecular Neurotherapy and Imaging Lab at Massachusetts General Hospital and Harvard Medical School, said in an official statement.

Experiments on mice have already been conducted, and proved very successful, according to Shah.

During the tests, the main brain tumor was surgically taken out, and then the stem cells were put at the site of the tumor in a biodegradable gel to kill the remaining cancerous cells.

Once the toxin is within the cancer cell, it disrupts its ability to create proteins, resulting in the death of the cell in a matter of days.

“After doing all of the molecular analysis and imaging to track the inhibition of protein synthesis within brain tumors, we do see the toxins kill the cancer cells,” he declared.

Shah said that the toxins that kill cancer have been used in coping with a few types of blood cancers. However, they were not very effective dealing with solid tumors because the cancer involved in those cases are not as accessible and the toxins in the stem cells don’t have enough time to kill the cancer, only having a short half-life.

But the new modified stem cells developed by Shah’s team are changing the situation.

"Now, we have toxin-resistant stem cells that can make and release cancer-killing drugs," he said.

The study was published in the journal Stem Cells, and could represent a breakthrough in cancer research, allowing the cancerous cells to be killed and the healthy ones to remain intact, as the toxins in stem cells only target the cancerous cells.

Scientists have applied for approval from the FDA to start the clinical trials of the method.

Experts praised the study as “the future” of cancer research.

“This is a clever study, which signals the beginning of the next wave of therapies. It shows you can attack solid tumors by putting minipharmacies inside the patient which deliver the toxic payload direct to the tumor,” Chris Mason, a professor of regenerative medicine at University College London, who was not participating in the study, told the BBC.