Malaria Parasites Show Promise as Cancer-Killing Therapy

Malaria protein is able to attack more than 90 percent of all tumor types.

In searching for a vaccine to fight against malaria in pregnant women, researchers have instead found what appears to be an effective weapon against cancer.

Researchers from the University of Copenhagen (UCPH) and the University of British Columbia (UBC) discovered this possible breakthrough, which may result in a significant medical treatments for cancer.

During the study, researchers found that armed malaria proteins can kill cancer.

The carbohydrate that malaria parasites attach to in the placenta of pregnant women is identical to a carbohydrate found in cancer cells, according to malaria researcher Ali Salanti, a professor from the Faculty of Medical Health and Sciences, UCPH.

The scientists subsequently recreated the protein the malaria parasite uses to attach to the placenta and added a toxin to it. This combination regimen seeks out cancer cells, absorbs into them, releases a toxin inside, and results in cancer cell death.

The process was observed in both cell cultures and in mice with cancer.

“For decades, scientists have been searching for similarities between the growth of a placenta and a tumor,” Salanti said. “The placenta is an organ, which within a few months grows from only few cells into an organ weighing approximately 2 pounds, and it provides the embryo with oxygen and nourishment in a relatively foreign environment. In a manner of speaking, tumors do much the same, they grow aggressively in a relatively foreign environment.”

According to Salanti, the carbohydrate’s function in the placenta helps to ensure fast growth.

Experiments showed that it had the same function in cancer tumors. Combining the malaria parasite with cancer cells resulted in the attachment of the parasite to cancer cells.

The research groups tested thousands of samples from brain tumors to leukemia, with the results showing that malaria protein is able to attack more than 90% of all tumor types.

The drug was tested in mice with 3 different types of human tumors. Mice with non-Hodgkin’s lymphoma treated with the regimen had tumors about a quarter the size of tumors in the control group.

Two of the 6 mice with prostate cancer had no evidence of tumors just 1 month after receiving the first dose.

“It appears that the malaria protein attaches itself to the tumor without any significant attachment to other tissue,” said PhD student Thomas Mandel Clausen. “The mice that were given doses of protein and toxin showed far higher survival rates than the untreated mice. We have seen that three doses can arrest growth in a tumor and even make it shrink.”

With metastatic bone cancer, 5 out of 6 treated mice were alive after almost 8 weeks, compared with zero mice in the control group.

“We have separated the malaria protein, which attaches itself to the carbohydrate and then added a toxin. By conducting tests on mice, we have been able to show that the combination of protein and toxin kill the cancer cells,” said Mads Daugaard, head of the Laboratory of Molecular Pathology at the Vancouver Prostate Center at UBC in Canada.

The only downfall of this treatment is that it would not be available for pregnant women.

“Expressed in popular terms, the toxin will believe that the placenta is a tumor and kill it, in exactly the same way it will believe that a tumor is a placenta,” Salanti said.

The University of Copenhagen and scientists behind the discovery have collaborated to create a biotech company called VAR2pharmaceuticals, which will drive clinical development forward.

The teams are now fully focused on performing tests in humans within the next 4 years.

“The earliest possible test scenario is in 4 years’ time. The biggest questions are whether it’ll work in the human body, and if the human body can tolerate the doses needed without developing side effects,” Salanti said. “But we’re optimistic because the protein appears to only attach itself to a carbohydrate that is only found in the placenta and in cancer tumors in humans.”