Decoding multicellular interaction networks-a new horizon in tumor microenvironment research.

The tumor microenvironment (TME) milieu directs a plethora of tumor-modulating functions. Recent years have seen pivotal breakthroughs in our understanding of the TME's role in tumor initiation and progression, with tangible clinical applications. Individual components of the TME exert their function predominantly by cell-cell crosstalk, both in the form of physical interaction and secreted factors. Notably, different spatial niches represent exclusive signaling hubs in the TME, propagating pro- or antitumoral functions. The exploration of these interactions has been vastly facilitated by novel molecular technologies, each of which provides a different perspective on this intricate intercellular communication network. Together, these complementary methods paint a detailed, high-resolution map of the TME's interaction landscape. In this viewpoint, we explore how cellular interactions can unlock a new level of understanding of TME complexity, and discuss the promises and challenges of characterizing tumors based on their cellular interaction footprint.