Combining Synthetic, Natural Toxins Could Disarm Cancer, Drug-Resistant Bacteria

Cancer researchers from Rice University suggest that a new human-made drug that's already proven effective at killing cancer and drug-resistant bacteria could best deliver its knockout blow when used in combination with drugs made from naturally occurring toxins.

"A wealth of research in recent years has shown that both cancer and bacteria can mount sophisticated, coordinated defenses against almost any drug," said José Onuchic of Rice's Center for Theoretical Biological Physics (CTBP). "By combining drugs, particularly those that place stress on different parts of the cell, we expect it will be possible to knock out either cancer cells or bacteria while simultaneously inhibiting their ability to become drug-resistant."

Researchers built a right-handed, "counterclockwise" version of the antimicrobial peptide KLAKLAK-2 called D-KLAKLAK-2, with the "D" denoting right-handedness. D-KLAKLAK-2 is an effective killer of Gram-negative bacterial pathogens, including several types that have grown resistant to traditional antibiotics.

Naturally occurring antimicrobial peptides are chemical weapons that bacteria themselves have developed over millions of years in their never-ending war among themselves. The team reasons that combining these natural toxins with human-made mirror drugs will create the drug equivalent of a one-two punch. The combination should "confuse" bacteria and cancer and prevent them from rapidly becoming resistant to the human-made drugs.