1.17.1 Cancer Cell Adhesion Definition

Cancer Cell Adhesion Definition is a description of the specific pattern of cell-cell and cell-matrix adhesive activity present within a cancer cell, considered in terms of how this pattern differs from the corresponding adhesive behavior present in a normal, non-cancerous cell, including alterations in the abundance, distribution, or function of adhesion molecules that collectively distinguish the adhesive behavior of a cancer cell from that of its normal counterpart.

Conceptual Basis

An Altered Version of Conserved Adhesive Mechanisms

Cancer cell adhesion is built upon the same fundamental cell-cell and cell-matrix adhesion molecules present in normal cells, but is defined by the specific alterations distinguishing their function within a cancer cell context, including changes in the level of expression of particular adhesion molecules, changes in their subcellular distribution, or changes in the downstream signaling consequences that follow from their engagement.

Alteration Rather Than Simple Loss

Cancer cell adhesion is not uniformly characterized by a simple, wholesale loss of all adhesive capacity; rather, it typically reflects a selective and distinctive pattern of altered adhesion, in which some adhesive interactions are diminished while others may be newly acquired or enhanced, relative to the adhesive configuration present in the corresponding normal cell.

Characteristic Features

Reduced Cell-Cell Adhesion

A recurrent feature of cancer cell adhesion is reduced strength or stability of the adhesive contacts connecting a cancer cell to its neighboring cells, weakening the physical integration of the cell within its surrounding tissue relative to the tight cell-cell contacts characteristic of normal, tissue-resident cells.

Altered Cell-Matrix Adhesion

Cancer cell adhesion frequently involves altered engagement with the surrounding extracellular matrix, including changes in which matrix-binding adhesion molecules are expressed and how strongly the cell attaches to particular matrix components, a shift that can facilitate altered interaction with, and movement through, the surrounding extracellular environment.

Altered Adhesion-Associated Signaling

Beyond changes in the physical strength of adhesive contacts, cancer cell adhesion commonly involves altered signaling consequences arising from those contacts, such that the same adhesive interaction that would normally restrain proliferation in a properly attached normal cell may instead permit continued proliferation within the altered signaling context of a cancer cell.

Consequences of Altered Adhesion

Reduced Tissue Integration

Because reduced cell-cell adhesion weakens the physical connections holding a cell within its surrounding tissue, cancer cells exhibiting this altered adhesion pattern are more prone to detachment from their original tissue location relative to normal cells maintaining strong, stable cell-cell contacts.

Facilitated Movement and Invasion

Altered cell-matrix adhesion, permitting a more dynamic and less stable pattern of attachment to the surrounding matrix, contributes to the capacity of cancer cells to move through and invade the surrounding extracellular environment, a behavior that would be substantially constrained under the stable matrix attachment characteristic of normal cells.

Relationship to Broader Cancer Cell Biology

Foundation for Invasive and Disseminated Behavior

The specific pattern of adhesion alteration present within a given cancer cell provides the mechanistic foundation from which subsequent behavioral characteristics, including local invasion and dissemination to distant sites, arise as downstream consequences of the underlying adhesive configuration.

A Variable, Cell-Specific Configuration

Because different cancer cells can exhibit distinct combinations of retained, diminished, or newly acquired adhesive interactions, cancer cell adhesion is not a single fixed configuration but a variable state whose specific characteristics differ according to which components of the underlying normal adhesion system have been altered in a given cell lineage.