Identifying the interactions that drive cell migration in brain cancer

To move forward or migrate, the different cells in our body must exert forces or interact with their surrounding environment. Interestingly, however, a fault in these interactions can also be the reason for the spread of deadly cancer cells, such as in a brain tumor, or glioblastoma. While the importance of these interactions is well-understood, the machinery involved in these interactions at the molecular level remains a mystery.

Now, a team of researchers led by Professor Naoyuki Inagaki from Nara Institute of Science and Technology, Japan, along with Dr. Yonehiro Kanemura from NHO Osaka National Hospital, Japan; Dr. Tatsuo Kinashi from Kansai Medical University, Japan; and Dr. Daisuke Kawauchi from Nagoya City University, Japan, has identified the underlying mechanism involving a protein called shootin1b that promotes cell migration or movement in glioblastoma.

The study is published online in Advanced Science.

“We discovered that an abnormal activity of shootin1b promotes the movement of cancer cells and spread of glioblastoma, the most common and difficult to treat brain tumor in adults,” explains Professor Inagaki.

Notably, the study sheds light on a newly discovered molecular interaction that drives rapid migration of dendritic cells, a type of immune cell that capture pathogens. Migrating dendritic cells need to exert backward forces onto the environment to propel themselves forward.

In addition, different environmental cues in the form of chemoattractants (molecules that attract moving cells), regulate their speed and direction. At the front of migrating cells, intracellular actin (a protein that generates force and movement in the cell) filaments polymerize, generating a backward flow of actin.

Shootin1b forms clutches that link the cell’s internal actin to the external environment through adhesive molecules, converting this backward actin movement into traction force that propels the cell forward.

This adhesion–clutch system mediates cell movement depending on the chemoattractant force. Shootin1b and the adhesion molecule transmit weak traction forces, which are well-suited for rapid cell migration, presenting a potential target for preventing the spread of glioblastoma.

“By suppressing the abnormal activity of shootin1b, we can prevent the migration of glioblastoma cells and spread of cancer. Thus, shootin1b could be a novel therapeutic target for glioblastoma,” says Professor Inagaki.

To put these findings into context, glioblastoma has a five-year survival rate of only 5%, and the targeted suppression of glioblastoma invasion by inhibiting the abnormal activity of shootin1b could bring a ray of hope in the lives of many. Thus, these findings can pave the way for the development of new treatment strategies for this highly intractable cancer.