PTK2 and neoplasm: For example, in aged tissues, stiffness increases from approximately 1–2 kPa to 3–5 kPa, and tumors can reach levels of 10–20 kPa, and the stiffness magnitude varies in different tumor conditions, which are sufficient to trigger integrin clustering and FAK/Src activation—a biomechanical signal that enhances integrin clustering and focal adhesion formation or YAP/TAZ signaling pathways [40,41,42].