Contact normalization is a process by which intercellular junctions mediate signals that allow normal cells to inhibit the transformed growth of neighboring

tumor A neoplasm () is a type of abnormal and excessive growth of tissue. The process that occurs to form or produce a neoplasm is called neoplasia. The growth of a neoplasm is uncoordinated with that of the normal surrounding tissue, and persists ...

cells. Intimate junctional contact between tumor cells and normal cells is needed for this form of growth control. Contact normalization describes the ability of nontransformed cells to normalize the growth of neighboring cancer cells. This is a very widespread and powerful phenomenon. Tumor cells need to overcome this form of growth inhibition before they can become

malignant Malignancy () is the tendency of a medical condition to become progressively worse. Malignancy is most familiar as a characterization of cancer. A ''malignant'' tumor contrasts with a non-cancerous ''benign'' tumor in that a malignancy is not s ...

metastatic Metastasis is a pathogenic agent's spread from an initial or primary site to a different or secondary site within the host's body; the term is typically used when referring to metastasis by a cancerous tumor. The newly pathological sites, then, ...

. Induction of a select set of genes has been associated with the ability of cancer cells to escape contact normalization. These include podoplanin (

PDPN Podoplanin is a protein that in humans is encoded by the ''PDPN'' gene. Structure and function Podoplanin is a mucin-type protein with a mass of 36- to 43-kDa. It is relatively well conserved between species, with homologues in humans, mice, rat ...

), vascular endothelial growth factor receptor 2/

kinase insert domain receptor Kinase insert domain receptor (KDR, a type IV receptor tyrosine kinase) also known as vascular endothelial growth factor receptor 2 (VEGFR-2) is a VEGF receptor. ''KDR'' is the human gene encoding it. KDR has also been designated as CD309 (cluster ...

(

VEGFR2 Kinase insert domain receptor (KDR, a type IV receptor tyrosine kinase) also known as vascular endothelial growth factor receptor 2 (VEGFR-2) is a VEGF receptor. ''KDR'' is the human gene encoding it. KDR has also been designated as CD309 (cluster ...

/KDR), and transmembrane protein 163 (TMEM163) receptors.

* Rubin H. (2008) Contact interactions between cells that suppress neoplastic development: can they also explain metastatic dormancy? Adv Cancer Res. 100:159-202. * Rubin H. (2008) Cell-cell contact interactions conditionally determine suppression and selection of the neoplastic phenotype. Proc Natl Acad Sci U S A. 105:6215-21. * Krishnan H. and Goldberg G.S. (2015) Contact normalization or escape from the matrix. In: Kandous, M. (Eds.) Intercellular communication and Cancer. pp. 297–342. Heidelberg: Springer-Verlag. {{DEFAULTSORT:Contact Normalization Cell communication Intercellular junctions Oncology

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