Proliferation is a fundamental and highly conserved characteristic of living systems, and in the context of cancer, it becomes a deregulated process. In a healthy organism, most cells cease to proliferate even in the presence of nutrients and mitogens, entering a reversible state of quiescence. This raises several questions: What regulates quiescence? How is it disrupted in cancer? Why are certain organs more prone to tumor development? Evidence suggests that the extracellular matrix, a microenvironment component, plays a crucial role in the cell’s decision to either proliferate or remain quiescent. Utilizing a CRISPR/CAS9 library, we aim to dissect the signaling pathways involved in regulating extracellular matrix-induced quiescence and track the dynamics of quiescence acquisition at the single-cell level. This research could potentially uncover molecular-level insights into how the microenvironment governs proliferation and how the control of quiescence is compromised in cancer.