Our old friend, Dr. Kenneth Anderson, is at it again! Check-out excerpts from Dana Farber’s website about an experimental anti-myeloma molecule, P5091:
Molecule shows effectiveness against drug-resistant myeloma
Posted On: September 10, 2012
BOSTON––A molecule that targets the cell’s machinery for breaking down unneeded proteins can kill multiple myeloma cancer cells resistant to the frontline drug Velcade, researchers at Dana-Farber Cancer Institute have found.
In a study published online by the journal Cancer Cell, the investigators report that the small molecule P5091 triggered apoptosis — programmed cell death — in drug-resistant myeloma cells grown in the laboratory and in animals. The anti-myeloma effect was even more powerful when researchers combined P5091 with other therapies.
“Velcade was one of the first of a class of drugs known as proteasome inhibitors to be approved by the U.S. Food and Drug Administration for multiple myeloma treatment,” says Dharminder Chauhan, PhD, lead author of the paper with Ze Tian, PhD, both of Dana-Farber. “While Velcade is successful in many patients with multiple myeloma, it often loses its effectiveness over time, which prompted us to seek other drug targets.”
OK. So far, so good. Let’s skip the rest and jump to the conclusion:
“In laboratory cell cultures, P5091 resulted in the death of myeloma cells,” said the study’s senior author, Kenneth Anderson, MD, director of the Jerome Lipper Multiple Myeloma Center and the LeBow Institute for Myeloma Therapeutics at Dana-Farber. “In animal models of myeloma, this molecule impaired tumor growth, prolonged survival, and didn’t harm normal tissue.” When researchers combined P5091 with the drugs lenalidomide, SAHA, or dexamethasone, the myeloma-killing effects were even more pronounced.
Although P5091 itself has not been formulated into a drug, the study demonstrates “that you can target molecules in the ubiquitin proteasome system without targeting the proteasome itself and still achieve a cancer cell-killing effect, with no significant toxicity,” Chauhan remarks. “Our results lay the groundwork for testing USP7 inhibitors, either alone or in combination with other drugs, in patients with multiple myeloma.”
I just ran a post about P5091 on my MyelomaNews.com site about this same article yesterday. But I know most of you don’t visit there very often, so I wanted to get this info to as many of you as possible.
As always, we shouldn’t get too excited about this, considering testing has only been done in the lab. But what interests me is the fact that these myeloma experts know what they are looking for: another option for patients who have become refractory to Velcade.
Feel good and keep smiling! Pat