Xavier Trepat

An opinion piece by IBEC group leader Xavier Trepat has appeared in the News and Views section of the current issue of Nature, which is devoted to ‘Bottom-up biology’.

In his piece ‘Bottom does not explain top’, Xavier argues that understanding how complex biological structures – or even entire cells – are built can only provide a certain amount of insight into how biological systems function at higher levels of organization. There are many variables such as density, or even pathologies suffered by the subject, that affect cell behavior at the mesoscale – that is, at the longer, more ‘system-level’ scale than that of the individual components of an organism. Cells in a group, for example, can sense or respond to external stimuli that an individual cell cannot identify.

One of the most enviable features of superheroes is their ability to stretch their bodies beyond imaginable limits. In a study published today in Nature, scientists have discovered that our cells can do just that.

With every beat of the heart and every breath into the lungs, cells in our body are routinely subjected to extreme stretching. This stretching is even more pronounced when cells shape our organs at the embryo stage, and when they invade tissues through narrow pores during cancer metastasis – but how cells undergo such large deformations without breaking has remained a mystery until now.

The embryonic stem cells that form faces – neural crest cells – use an unexpected mechanism to develop our facial features, according to a new UCL-led study involving IBEC researchers.

By identifying how these cells move, the researchers’ findings could help understand how facial defects, such as cleft palate and facial palsy, occur.

This newly described mechanism is likely to be found in other cell movement processes, such as cancer invasion during metastasis or wound healing, so the findings may pave the way to developing a range of new therapies for these, too.

Researchers from IBEC and UB have discovered that the way tumor cells expand defies the laws of physics.

In an article published today in Nature Physics, the researchers have challenged our current understanding of the discipline and developed a new framework that could help predict the conditions under which tumors initiate metastasis.

A review by IBEC group leader and ICREA research professor Xavier Trepat is one of six featured in Nature Physics’ latest ‘Insight’ issue, ‘The Physics of Living Systems’, in which all the articles have been co-authored by a physicist and a biologist.

Penned together with collaborator Erik Sahai from London’s Francis Crick Institute, Xavier’s article, ‘Mesoscale physical principles of collective cell organization’, reviews recent evidence showing that cell and tissue dynamics are governed by mesoscale physical principles – force, density, shape, adhesion and self-propulsion.