"Drugs are far more effective if they're delivered
through the membrane, directly into the cell," said lead researcher
Andrew Barron. "Viruses, which are often toxic, long ago developed
ways of sneaking through cell walls. While we're mimicking some
techniques used by viruses, we're using non-toxic pieces of protein,
and we're incorporating buckyballs as a passkey."
The passkeys that Barron and colleagues developed
contain a molecule called Bucky amino acid that was created in
Barron's lab. Bucky amino acid, or Baa, is based on pheylalanine, one
of the 20 essential amino acids that are strung together like beads on
a necklace to build all proteins.
Barron's graduate student, Jianzhong Yang,
developed several different Baa-containing peptides, or slivers of
protein containing about a dozen or so amino acids. In their natural
form, with pheylalanine as a link in their chain, these peptides did
not pass through the cell walls.
Barron's group collaborated with Yang's brother,
Baylor College of Medicine assistant professor Jianhua Yang at Texas
Children's Cancer Center, and found the Baa-containing peptides could
mimick viral proteins and pass through the walls of cancer cells. The
peptides were found effective at penetrating the defenses of both
liver cancer cells and neuroblastoma cells.
"Neuroblastoma is the most common extracranial
solid tumor in children, and it is responsible for about 15 percent of
pediatric cancer deaths," said Jianhua Yang. "Our findings are
significant because neuroblastoma cells are well-known for their
difficulty in transfection through the cell membrane."
Barron is Rice's Charles W. Duncan Jr.-Welch
Professor of Chemistry, professor of materials science and associate
dean for industry interactions and technology transfer. |