Research with an insect peptide challenges the popular belief that cancer cell membranes don't make good drug targets.
Cell membranes could use a little more respect. No one doubts that the inner machinery of cells is fascinating in its complexity, but membranes themselves are often viewed as rather boring containers that are pretty much the same no matter where you look. But membranes are actually highly complex structures consisting of hundreds of different lipids and proteins, often varying in composition among cell types. Still, even many cell biologists have perhaps not realized the implications this diversity could have for drug discovery.
There's an insect that knows a thing or two about selectively targeting cancer cell membranes. The Brazilian wasp Polybia paulista produces a peptide called MP1, which unexpectedly creates disruptive pores on cancer cells' surfaces while leaving normal cells alone. Now, scientists have a clearer picture of why this peptide is selective.[1,2] Cancer cells have relatively high levels of phospholipids called phosphatidylserine (PS) and phosphatidylethanolamine (PE). Using various imaging techniques, the researchers found that the peptide, when bound to PS and PE together with a common cell membrane component, formed large pores that the cancer cell could not close, causing fatal leaks to the cell.
This peptide may be worth further investigation in the field of oncology. But there is also a larger message in that cell membranes, often thought to be too alike to be of any use in targeting cancer, have distinct features in cancer cells. Drug discovery could benefit by exploring these differences and exploiting them to attack cancer cells while leaving normal cells alone.
We at HemaCare are constantly reminded that cancer research is full of unexpected surprises. For scientists working on their own eye-raising discovery, we offer a wide variety of well-characterized human disease state primary cells and blood components, including those from several cancers.
2. Leite, NB et al. PE and PS lipids synergistically enhance membrane poration by a peptide with anticancer properties.