Clustered nanoparticles deliver chemo to fight drug-resistant ovarian cancer

Clusters of nanoparticles deliver chemotherapy to an ovarian tumor--Courtesy of Tel Aviv U.

To tackle difficult-to-treat drug-resistant ovarian cancer, researchers at Tel Aviv University have developed nanoparticles designed to accumulate in clusters in tumors to deliver chemotherapy, increasing efficacy and reducing side effects.

The nanoscale therapy demonstrated a 25-fold increase in chemo drugs that accumulated in ovarian tumors in mice, according to a report from the university. This comes about because of the unique composition of the nanoparticles, which the scientists call "gagomers" when they cluster.

The particles are made of fat and the clusters are coated with polysugars, which signals to receptors on drug-resistant tumor cells that it's time to release the drugs, but slowly and not all at once. They are designed to kill off cancer cells within 24 to 48 hours. Chemotherapy alone has a tendency to move too fast, causing it to be rejected by the cancer cell.

"Tumors become resistant very quickly," lead researcher Dan Peer said in a statement. "Following the first, second and third courses of chemotherapy, the tumors start pumping drugs out of the cells as a survival mechanism. Most patients with tumor cells beyond the ovaries relapse and ultimately die due to the development of drug resistance. We wanted to create a safe drug delivery system, which wouldn't harm the body's immune system or organs."

Peer, whose family has felt the sting of ovarian cancer, and his team published the study on Feb. 4 in the journal ACS Nano.

"At the end of the day, you want to do something natural, simple and smart," Peer said. "… We hope the concept will be harnessed in the next few years in clinical trials on aggressive tumors."

- here's the university announcement
- get the research abstract