Apical–Basal Polarity as a Sensor for Epithelial Homeostasis: A Matter of Life and Death

Abstract Purpose of Review Epithelial cells line tissues and serve an important functional role in maintaining a barrier between tissue compartments and protection from the external environment. Tight Junctions and apical–basal polarity function to establish and maintain epithelial structures to prevent leakage between cells and define distinct subcellular domains to localize signaling pathways within cells that control growth, survival, and migration. Disruption of tight junctions and cell polarity is frequently observed in cancer. Recent Findings In this review, we discuss a role for Tight Junctions and the Par polarity complex as a sensor of epithelial integrity that contributes to maintaining epithelial homeostasis through apoptosis, proliferation, and stem cell renewal, and that disruption of these processes contributes to cancer progression. Summary Epithelial homeostasis is maintained by the spatial organization of signaling pathways within cells. Damaged cells are eliminated from the tissue by extrusion and apoptosis, and are balanced by proliferation and differentiation. Understanding the control of these processes during normal tissue development and homeostasis will lead to a more complete view of the etiology of cancer.
Source: Current Pathobiology Reports - Category: Laboratory Medicine Source Type: research