The concept of invadosomes in Molecular Cell Biology.
I am
quite excited to hear about the concept of 'invadosome' in cell biology today.
It is a set of spectacular cellular apparatus which acts as cell contacts when
either some types of normal cells or tumor cells want to invade other cells,
that is why it is important. The key component of the invadosome is related to
its cytoskeletal machineries (in this case the F-Actin). When cellular signals,
normal or nefarious, stimulate
the corresponding cells, the assembly of F-actin takes place and the action is
enhanced by a whole series of cytoskeletal proteins. Since focal adhesion is
highly important for holding the cells together, it is not surprising at all to
learn that focal adhesion kinase (FAK) will enhance the cytoskeletal action
here. The completion of F-actin assembly will mobilize a whole series of
extracellular matrix (ECM) - degradation machineries (such as
metalloproteinases) - which will then chew up the web-like structure of the
extracellular matrix.
A personal observation
from this insightful poster is that - the invadopodia (i.e. the bad guy which
is related to cancer) is more 'sinister' than you bet. From the morphological
diagrams, you can see that the structure of the invadopodia is far more angular
and tight-knitted than the 'good guy' known as podosome. This appears to me
that the invadopodia is 'ready to shoot', as an angular stance will provide a
better focal adhesion strategy. This is indeed supported by the observations
that these invadopodias are larger in size, they have longer persistence and
have superior caliber in degrading ECM. Another fascinating question is - is
there a dynamic equilibrium between the 2 types, i.e. can they interconvert? If
the answer is yes, we will have to find out the conditions as this will be an
important issue! A fascinating concept!
by Ed Law
9/2/2015
For the poster, please see:
Reference:
1. http://jcs.biologists.org/content/122/17/3009/F1.poster.jpg
2. http://www.cnb.csic.es/~meetinginvadosome/scientific-progamme.html
