Minicells Are A Surprisingly Successful Next Step In Cancer Treatment

By Nick Venable | Published

Hey, Big Government and Big Pharma, science is catching up. No, I’m not actually that kind of conspiracy theorist, but like many other people, I’ve naively wondered why cancer treatments seemed to be stuck in stasis. I know it’s worlds more complicated than “Chemo and radiation might help,” but that is what it boils down to.

The journal Nature Biotechnology reports that Australian researchers, including molecular biologist Dr. Himanshu Brahmbhatt, have treated tumor cells of mice using minicells, made from bacteria and short interference RNA (siRNA), which counteract the cancer cells’ genes responsible for resisting drug treatments. Once those cells are weakened, they become sensitive to chemotherapy treatments again. Seems obvious, doesn’t it?

Well, it was previously thought that siRNA couldn’t pass through cell membranes due to their size, but bacterial membranes contain protein channels that siRNA can enter. The outsides of the minicells are coated with antibodies, which lock onto receptors in tumor cells. The minicells then enter the cancer cells and break down to where the siRNA is dispersed throughout the cell. Because this particular effect happens intra-cellularly, no toxic effects have been found.

The study shows the minicell/chemo treatment stalls the growth of normally drug-resistant tumor xenographs, man-made tumors, for up to four months. Beyond mice, the researchers moved on to dogs with relapsed cancers, and the results were the same, proving that real cancers are just as vulnerable to the treatment.

Medical oncologist Stephen Clarke says we’re a long way from clinical use of this treatment, and more research has to be done. He says it’s possible the antibodies would create an immune response in the tumor cells, negating the positive effect. It’s also possible not every type of tumor cell would accept the antibodies. Even so, Brahmbhatt says his team is to begin human tests in the next few months, but only with drug-loaded minicells. Once it’s determined the minicells don’t cause any negative side effects, in six to twelve months they’ll begin dual treatment.

Both sides of my family have been affected by different forms of cancer, and I’m constantly fearful of the day when I too will fall victim. And though I don’t hold out hope for any miracle cures to be invented in my lifetime, it’s certainly exciting to see ways of making current treatments far more successful.