Experiments in laboratory mice have shown that blocking a protein, called a fractalkine receptor, on ovarian cancer cells can halt the cancer’s spread to nearby locations.

The study by researchers at the University of Illinois-Chicago, “Emergent role of the fractalkine axis in dissemination of peritoneal metastasis from epithelial ovarian carcinoma,” appeared in the journal Oncogene.

Ovarian cancer is more common in post-menopausal women; its symptoms include bloating, pelvic or abdominal pain and problems with the urinary tract. Ovarian cancer is often detected after it has spread to other parts of the body, making it difficult to treat.

The American Cancer Society estimates that 22,440 American women will be diagnosed with ovarian cancer this year and 15,000 will die of the disease, which ranks fifth in cancer deaths among women and No. 1 among cancers of the female reproductive system.

About 64 percent of specimens from metastatic, or spreading, ovarian cancers, have proteins on their surfaces called fractalkine receptors. When another protein reacts with the receptor, it helps the cancer to spread, or metastasize. Blocking fractalkine receptors could potentially lessen or stop metastasis.

Since many cancer drugs target receptors in the family to which fractalkine receptors belong, the researchers tried blocking fractalkine receptors to see if that slowed or prevented the cancer’s spread. They used lab mice to test this idea by lowering the production of receptors in tumors in mice ovaries. Researchers found that the tumors did not spread to nearby sites, including the liver, bower or peritoneal wall (a structure that surrounds and supports the abdominal organs).

“The greatest barrier to our ability to treat cancer in this stage is that we know very little about the molecules that cause the disease to spread,” said Maria Barbolina, associate professor of biopharmaceutical sciences and the study’s lead researcher. “The goal of our research is to identify key molecules that govern metastasis and use them as targets for the development of new drugs.”