Epithelial-Mesenchymal Transitions

Tumors result, surprisingly, from normal developmental processes. The same genes that can cause cancer to develop are vital for embryonic development. This relationship applies to tumor formation and progression of tumor cell invasiveness. Because of this, epithelial-mesenchymal transitions are being studied to explain this relationship.

EMT is the transition of the mesenchymal cells that are meant to be epithelial cells, but instead become cancerous cells. Mesenchymal cells are unspecialized cells, which are part of the embryonic mesoderm, from which connective tissue, bone, cartilage, and the circulatory and lymphatic systems develop. During EMT, epithelial cells lose cell-cell adhesion and cytoskeletal components. This process results in these cells expressing mesenchymal components and a migratory phenotype. EMT is required during gastrulation and its subsequent products rely on EMT to form properly. EMT was discovered as a part of embryogenesis in the early 1980’s and was soon linked to cancer. Although this was not initially accepted, further evidence suggests EMT is important to the progression of cancer.

The loss of E-cadherin is an important indicator of EMT. E-cadherin is essential to cell-cell adhesion, the formation of epithelia in the embryo and the maintenance of epithelial homeostasis. Because of E-cadherin loss, tumor cell invasiveness increases. Often times, tumor progression and the level of E-cadherin are inversely related. Studies show that the E-cadherin gene suppresses the production of tumors. In many cases E-cadherin expression is lost because of transcription factors.

Home • Cancer and Embryology • Epithelial-Mesenchymal Transitions
Transcription Factors • Authors