Israeli researchers have turned to nanotechnology to target drug-resistant ovarian tumors. Ovarian cancer accounts for more deaths of American women than any other cancer of the female reproductive system. According to the American Cancer Society, one in 72 American women will be diagnosed with ovarian cancer, and one in 100 will ultimately die of the condition.

Now Prof. Dan Peer of Tel Aviv University’s Department of Cell Research and Immunology has proposed a new strategy to tackle an aggressive subtype of ovarian cancer using a new nanoscale drug-delivery system designed to target specific cancer cells.

Peer and his team — Keren Cohen and Rafi Emmanuel from Peer’s Laboratory of Nanomedicine and Einat Kisin-Finfer and Doron Shabbat, from TAU’s Department of Chemistry — have devised a cluster of nanoparticles called gagomers, made of fats and coated with a kind of polysugar. When filled with chemotherapy drugs, these clusters accumulate in tumors, producing dramatically therapeutic benefits.

The objective of Peer’s research — to provide a specific target for anti-cancer drugs to increase their therapeutic benefits, and to reduce the toxic side effects of anti-cancer therapies.

The study was published in February in the journal ACS Nano.

According to Peer, traditional courses of chemotherapy are not an effective line of attack as the chemotherapy drug is almost immediately ejected by the cancer cell, severely damaging the healthy organs that surround it and leaving the tumor cell intact.

“Tumors become resistant very quickly. Following the first, second, and third courses of chemotherapy, the tumors start pumping drugs out of the cells as a survival mechanism,” said Peer. “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 and his colleagues saw a 25-fold increase in tumor-accumulated medication and a dramatic dip in toxic accumulation in healthy organs using the new therapy.

Peer chose to tackle ovarian cancer in his research because his mother-in-law passed away at the age of 54 from the disease. “She received all the courses of chemotherapy and survived only a year and a half,” he said. “She died from the drug-resistant aggressive tumors.

“At the end of the day, you want to do something natural, simple, and smart. We are committed to try to combine both laboratory and therapeutic arms to create a less toxic, focused drug that combats aggressive drug-resistant cancerous cells,” said Peer. “We hope the concept will be harnessed in the next few years in clinical trials on aggressive tumors.”