This method of starving cancer cells could provide new options for patients, particularly those resistant to standard therapies such as tamoxifen, Georgia Health Sciences University researchers said.
Human estrogen receptor-positive breast cancer cells thriving in a Petri dish or transplanted onto mice die when exposed to a drug that blocks the transporter, called SLC6A14, said Dr. Vadivel Ganapathy, Chairman of GHSU's Department of Biochemistry and Molecular Biology.
"It basically starves the cancer cell," said Ganapathy, corresponding author of the study published in the Journal of Biological Chemistry. The transporter can carry 18 of the known 20 amino acids, fuel all cells need in some combination. Amino acids enable cells to make proteins, which they need to function and survive. The cell type determines its amino acid needs and delivery system. Rapidly growing, dividing estrogen receptor-positive breast cancer needs nearly every amino acid so it makes the smart choice of utilizing the transporter that can deliver the biggest load, Ganapathy said.
SLC6A14 is the only transporter known to carry all 10 essential amino acids, essential because the body can't make them so they have to be delivered via the bloodstream from food. The transporter also takes eight of the nonessential amino acids along for the ride, Ganapathy said.
And it is a fast ride. The transporter has three energy sources instead of the usual one or two, he said.
Interestingly, SLC6A14 is expressed at low levels in most of the body. "There are specialized features of this transport system which could be used by every cell to its advantage but they do not seem to do that. It's expressed only at low levels in normal tissues," Ganapathy noted. While that may seem like a loss for healthy cells, it bolsters the cancer-fighting potential for drugs that block SLC6A14 by making it a more specific cancer target. "Since the normal cells do not depend on this transporter, you can use a drug that selectively blocks it to target cancer cells" Ganapathy said.
The compound they used is alpha-methyl-DL-tryptophan, already used in humans for short periods when they are getting a PET scan in certain areas of the brain. When the researchers treated estrogen receptor-positive breast cancer cells with it or put it in the drinking water of the mice with the cells, rapid growth stopped and the cancer cells died. Further studies showed alpha-methyl-DL-tryptophan seemed to impact only cells expressing the SLC6A14 transport system. Even another type of breast cancer, estrogen receptor-negative, wasn't impacted.
Researchers are now determining the most potent version of the compound.
The research was supported by the National Institutes of Health.
Toni Baker | EurekAlert!
Novel mechanisms of action discovered for the skin cancer medication Imiquimod
21.10.2016 | Technische Universität München
Second research flight into zero gravity
21.10.2016 | Universität Zürich
Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.
"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...
In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.
A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...
By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.
"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...
COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.
In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...
'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.
Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...
14.10.2016 | Event News
14.10.2016 | Event News
12.10.2016 | Event News
21.10.2016 | Health and Medicine
21.10.2016 | Information Technology
21.10.2016 | Materials Sciences