Pregnant women are particularly vulnerable to the malaria parasite because it produces a protein that binds readily to a sugar molecule in the placenta. This same sugar molecule is also found in most cancers. Now, researchers have shown it is possible to attach anticancer drugs to the malaria protein and use it to deliver them precisely to tumors by targeting the sugar.
In the journal Cancer Cell, the team – including scientists from the University of British Columbia (UBC) in Vancouver, Canada – describes how the new approach halted the growth of various tumors in mice.
While the fact that the same sugar molecule (a type of chondroitin sulfate) is found in both the placenta and most cancers is not surprising – since both have cells that grow fast – the evidence for this has only surfaced recently, as senior author Mads Daugaard, an assistant professor of urologic science at UBC, explains:
“Scientists have spent decades trying to find biochemical similarities between placenta tissue and cancer, but we just didn’t have the technology to find it.”
Once the team discovered that the malaria parasite uses a protein it produces called VAR2CSA to embed itself in the placenta, they immediately saw the potential to use the process as a way to target cancer drugs to tumors, he adds.
Malaria protein drug targeted and killed cancer cells, shrank tumors
The researchers – aware of the irony that one deadly disease offers the means to cure another – tested their idea in two ways: first in cell lines and then in mice, using a drug that combines the malaria protein with an anticancer toxin.
In cell lines, they found that the combination drug specifically targeted and killed more than 95% of cancer cell lines.
And in mice implanted with three types of human tumors – the drug also showed varying degrees of success. In mice with non-Hodgkin’s lymphoma, the treated tumors shrank to a quarter of the size of untreated tumors.
With prostate cancer, the drug completely eliminated tumors in two of six treated mice within a month of administering the first dose, and with metastatic breast cancer, five of six treated mice were cured of the disease.
The researchers say the mice showed no adverse side effects from the treatment and their organs were unharmed by it.
Co-senior author Poul Sorensen, a UBC professor of pathology and laboratory medicine, concludes:
“This is an extraordinary finding that paves the way for targeting sugar molecules in pediatric and adulthood human cancer, and our groups are vigorously pursuing this possibility together.”
Two companies, one in Vancouver and the other in Copenhagen, Denmark, where some of the researchers are based, are already developing the drug and preparing it for human trials, which they believe will take 3-4 years.
Meanwhile, Medical News Today recently learned how nanodiamonds could help detect cancer early. A study published in the journal Nature Communications describes how a nanoscale, synthetic version of diamonds “light up” early-stage cancers in magnetic resonance imaging (MRI) scans.
Written by Catharine Paddock PhD