Scientist Discovers Protein That Causes Cancer to Spread

A major piece of the mystery surrounding cancer has been found: a scientist has discovered a protein that initiates the process that causes cancer to spread from the original tumor to other parts of the body. The report appears in Nature Cell Biology.

The process that releases cancer cells from their original tumor and allows them to spread throughout the body is called epithelial-mesenchymal transdifferentiation (EMT). The spread and development of the cancer cells into new tumors in other sites in the body is known as metastasis.

Cancer can begin in any tissue or organ in the body. The original tumor, or primary cancer, is usually named for the part of the body or type of cell in which the disease begins. When cancer cells break away from the primary tumor and form a new tumor in a different part of the body, the new tumor is a metastatic tumor.

According to the National Cancer Institute, the most common sites of metastasis from solid tumors are the lungs, bones, liver, and brain. Breast cancer commonly spreads to the bones, lungs, liver, or brain, while lung cancer often metastasizes to the brain or bones. Prostate cancer usually spreads to the bones. Metastasis is often the fatal blow in breast, ovarian, pancreatic, and colorectal cancers.

Ge Jin, a scientist from Case Western Reserve University School of Dental Medicine and the Lerner Research Institute at the Cleveland Clinic, discovered that a specific protein called disabled-2 (Dab2) turns on the EMT process. During the EMT process, some of the cancer cells separate from the surface of the tumor and transform into a type of cell (mesenchymal) that has the ability to migrate, which then allows metastasis to occur. A compound called transforming growth factor-B (TGF-B) triggers the formation of the Dab2 protein.

Jin, who was part of a six-member research team from the Department of Cancer Biology at the Lerner Research Institute, discovered that when researchers knocked out Dab2, the EMT process was not initiated. He noted that this discovery is a “major piece in cancer research that has been missing.”

This new discovery of a protein that causes cancer to spread is a critical piece in the cancer puzzle. According to Jin, “The process we discovered may lead to understanding how other diseases progress,” even beyond cancer.

SOURCES:
Case Western Reserve University
National Cancer Institute