Tumor invasion refers to the ability of cancer cells to penetrate and spread into surrounding tissues. This process is a key characteristic of cancer metastasis, where cancer cells break away from the primary tumor and spread to other parts of the body through the blood or lymphatic system. Understanding the mechanisms of tumor invasion is crucial for developing targeted therapies to prevent cancer metastasis and improve patient outcomes. Research in this area focuses on identifying the molecular and cellular factors that drive tumor invasion, as well as developing strategies to inhibit or block these processes. This field of study encompasses a wide range of disciplines, including cell biology, genetics, oncology, and pharmacology.