Met receptor tyrosine kinase signals through a cortactin-Gab1 scaffold complex, to mediate invadopodia

What's in a loop?

DNAs and proteins are major classes of biomolecules that differ in many aspects. However, a considerable number of their members also share a common architectural feature that enables the assembly of multi-protein complexes and thereby permits the effective processing of signals: loop structures of substantial sizes. Here we briefly review a few representative examples and suggest a functional classification of different types of loop structures. In proteins, these loops occur in protein regions classified as intrinsically disordered. Studying such loops, their binders and their interactions with other loops should reveal much about cellular information computation and signaling network architectures. It is also expected to provide critical information for synthetic biologists and bioengineers.

Pathological roles of invadopodia in cancer invasion and metastasis

Invadopodia are actin-rich membrane protrusions formed by invasive cancer cells. Invadopodia mediate the focal degradation of pericellular extracellular matrix (ECM) by the localized proteolytic activity of matrix metalloproteinases (MMPs). Over the last 2 decades, much progress has been made in identifying the molecular components of invadopodia and understanding the molecular mechanisms underlying their formation. Although the physiological and pathological roles of invadopodia have long been elusive, emerging evidence has begun to reveal their importance in local invasion during cancer metastasis. This review highlights recent findings on the roles of invadopodia in cancer invasion and metastasis and discusses the possibility of and strategies for targeting invadopodia formation for the development of novel anticancer therapeutics.