Cancer Cells Move in Groups, Similar to Birds and Sardines!

Researchers at IFOM (FIRC Institute of Molecular Oncology) and the University of Milan led by Professor Giorgio Scita have come up with a new finding with respect to movement of cancer cells – cancer cells move to other parts in a manner similar to that of a flock of birds. Cancer cells have some specific features – they grow rapidly, divide continuously and excessively and spread to other parts of the body. The process by which the cancer spreads to a neighboring or distant tissue or organ is referred to as metastasis. Metastatic invasion is usually a late stage in the disease and has limited treatment options.

In a recent paper published in the journal “Current Biology,” researchers have studied the spread of lymphocyte cancer cells and have postulated possible means to prevent the spread. Interestingly, the researchers found that cancer cells spread like migratory birds! We often see migratory birds flying in the sky in a group with a leader. Once the leader gets tired, another bird replaces it. A similar phenomenon occurs with cancer cells as well.

In their study, the researchers found that

• The ability of cancer cells to metastasize is increased when they move in a group rather than as single cells. A minimum of 23 cells aggregate together to migrate.
• The cells are more sensitive to the effect of chemical signals or chemokines when they are aggregated as compared to single or non-aggregated cells. They move in the presence of even low concentrations of chemokines.
• The aggregated cells move in perfect coordination, led by a lead cell. The lead cell is frequently replaced by one of the other cells, a phenomenon similar to that seen in nature.
• This regulated movement is paused in between so that the cells can evaluate the environment and change their direction if necessary.

This process of spread by aggregation has been noted for solid tumors like breast cancer, colon cancer and melanoma, beside blood cancer like chronic leukemia and lymphoma.

The research has an important inference:

• If cancer cells spread faster when they aggregate, molecules that interfere with or disrupt the aggregation of cells will reduce the ability of the cancer to spread.

Further research to identify such molecules could revolutionize the treatment of cancer. They will be able to prevent the spread of the cancer, which can then be treated by other available treatments, thereby improving the prognosis of the condition.

The research was conducted in collaboration with the Weizmann Institute of Science in Israel, the University of Toulouse, the National University of Singapore, and A*STAR of Singapore.

Credits: Image from the archives of the IFOM Mechanisms of tumour cell migration research unit directed by Giorgio Scita.