This document discusses three main topics: 1) Pericytes, not glial cells, are the primary cell type that forms scar tissue after spinal cord injuries. In the absence of pericytes, lesions do not scar over properly. 2) Increased rigidity of cancer cells activates proteins associated with cancer growth and metastasis. Applying mechanical forces to cells mimics this effect. 3) Discovering the role of pericytes and cell rigidity may help scientists develop new treatments for spinal cord injuries and cancer respectively.