The Mechanism of Ovarian Cancer Metastasis Revealed—Preventing It Is Next

Researchers have discovered why ovarian cancer spreads through the peritoneum, the abdominal lining, by metastasis . Some medicines that could prevent this process already exist, potentially enabling new treatments to stop ovarian cancer from spreading.

• What Is Ovarian Cancer? What Are Its Causes and Risk Factors? (Detailed)

In the United States alone, ovarian cancer is estimated to affect approximately 20.000 women annually. In Türkiye, it is the 7th most common cancer in women. Ovarian cancer is the most life-threatening reproductive system cancer, but early detection or prevention of spread improves the chance of successful treatment.

Only 15% of ovarian cancers are detected early, whereas in 75%, the tumor has already spread to the peritoneum.

What can stop metastasis? To answer this, researchers examined the metastatic process in high-grade serous ovarian cancer. The findings were published in Cancer Research .

Previous ovarian cancer studies showed that immune cells called macrophages are associated with worse outcomes when highly abundant in the tumor microenvironment. This study therefore investigated whether macrophages help cancer cells spread and attach to the peritoneum.

How Ovarian Cancer Metastasizes to the Abdominal Lining Has Been Discovered

Cell culture experiments showed that complex interactions between healthy and cancerous cells facilitate cancer spread.

Normally, the peritoneum is lined with cells called mesothelium ; mesothelial cells are abundant in membranes surrounding body cavities and internal organs.

This new ovarian cancer study showed that macrophages transform mesothelial cells into sticky cells that help cancer cells attach. Normal cells in the body can therefore trigger cancer cell spread.

The scientists then sought to identify the proteins responsible. Computational modeling revealed a protein chain reaction: macrophages secrete MIP-1β protein, causing mesothelial cells to produce an adhesive protein called P-selectin, which enables cancer cells to adhere.

Mouse studies confirmed the results. Finally, researchers examined human samples and found elevated MIP-1β and P-selectin levels in people with ovarian cancer.

Can Existing Medicines Stop This Process?

The approaches presented by this study may soon translate into productive new treatments. Existing medicines can block key aspects of the metastatic process identified. For example, an HIV medicine called maraviroc is known to block MIP-1β receptors.

If these findings are better substantiated, scientists will soon start testing existing medicines for clinical use to determine whether they cause significant toxicity in a phase-1 clinical trial .

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