The Prognostic Significance Of EpitheliaL Mesenchymal Transition Phenotype In Different Human Cancers

The epithelial-mesenchymal transition (EMT) roles importantly in cancer progression. It confersmore mesenchymal fibroblast-like phenotype and potentially enables and promotes the epithelialcancer cells to detach from the primary tumor location, traverse the basement membrane, andfinally leads to metastasis of cancer cells. It has been demonstrated that a series of distinctmolecular processes are involved in the EMT, such as the activation of some specific transcriptionfactors like Twist, Slug, ZEB1, ZEB2, Snail1, Snail2, changes in the expression of specific microRNAsand reorganization of some specific proteins like E-cadherin, N-cadherin, vimentin and fibronectin.The purpose of this review was to study the clinical significance and the prognostic impact of EMTphenotype in different human cancers. It has been suggested that the combination of the twomarkers of E-cadherin and vimentin could be reasonably used to identify the EMT in many cancers.It was revealed that EMT status is an important prognostic factor for pancreatic cancer andassociated with portal vein invasion and lymph node metastasis. Additionally, theImmunohistochemical study of breast cancer has shown a significant up-regulation of EMT markerslike vimentin, N-cadherin, and cadherin-11. The Immunohistochemical study of gastric cancer hasshown a significant decreased in expression of the adhesion molecules of E-cadherin, alpha and betacatenin in diffuse type of gastric cancer compared with intestinal cancer type suggesting that EMTmay be involved in determining the gastric cancer type and also resistance to treatment. Evaluationof proteins associated with EMT by using a tissue microarray method in the lung adenocarcinomahas been shown loss of cytokeratin, E-cadherin and acquisition of the expression of TTF-1, β-catenin, vimentin proteins. Gene expression analysis and immunohistochemistry study showed anupregulation of ZEB2 at the invasion front in primary colorectal cancer and liver metastases.Therefore, ZEB2 may be interesting as biomarker and potential target for treatment of colorectalcancer. The current review demonstrated the key role of EMT in carsinogenesis, so that they couldbe regarded as prognostic factors and targeting these key molecules could be a promisingtherapeutic alternative.