JAK protein contracts the cancer cells and facilitates their escape through a squeeze-out process

In a study published in the journal Cancer Cell, researchers from INSERM, France, the Institute of Cancer Research, London, and the University of Nice, France reported that the contraction of a cancer cell is caused by a protein called JAK, which facilitates cancerous cells to slip through tiny spaces and metastasize beyond the tumor area into other body parts.

The cancer cell endures muscle-like contractions with the “switching on” of JAK, which permits the cancer cells to shift and eventually slip out. The authors propose that metastasis (cancer spread beyond tumor area) can be restricted by developing drugs that could target JAK. Tumor metastasis accounts for nearly 90% of cancer-related deaths.

Cancer cells, tumor-associated healthy cells, and the cell matrix- all put together make up the tumor. Metastasis of cancer cells occurs when they escape from the tumor into new areas beyond the tumor via the matrix.

With forces similar to muscle contractions, in certain cancers, the cells elbow their way through the matrix; while in other cancers, the tumor-associated healthy cells facilitate movement of cancer cells through channels created by them.
According to researchers, identical methods are employed to generate a force in tumor-associated healthy cells and cancer cells.

Lead author Professor Chris Marshall, said: “There’s an urgent need to understand how tumors can spread from their site of origin, for example the skin, to other tissues, such as the lungs, liver and bone where the disease becomes more difficult to treat successfully.We’ve shown that the same protein called JAK triggers tumor spread via two different routes – it generates the force needed for cancer cells to move around the body and also for triggers healthy cells in tumours to create furrows in tissues down which cancer cells move. Encouragingly drugs that block JAK are already in development to stop the growth of tumours. Our new study suggests that such drugs may also stop the spread of cancer.”
Dr Lesley Walker, Cancer Research UK’s director of cancer information, said: “A huge challenge in successfully treating cancer is stopping it from spreading around the body, and keeping cancer that has already spread at bay. Most deaths from cancer are caused when cancer cells travel to different parts of the body and grow as secondary tumors. Discovering how cancer cells can funnel grooves though tissues, to squeeze away from primary tumors and spread to new sites, gives scientists fresh understanding of ways to stop cancer spread – literally in its tracks.”