β1 and β3 integrins in breast, prostate and pancreatic cancer: A novel implication.

Integrins are transmembrane glycoproteins that consist of an α and a β subunit. Specific integrin heterodimers preferentially bind to distinct extracellular matrix (ECM) proteins to affect the characteristics of cells or the components of the ECM. Among the different integrins, β1 and β3 integrins serve essential roles in the progression of different cancer-associated processes, including the initiation, proliferation, survival, migration and invasion. Furthermore, previous studies have revealed a ratio between these two integrins in cancer cells, which also demonstrated that the functions of these two integrins are paradoxical. This indicated that the proliferation and metastasis of cancer cells are not always parallel and may be considered independently maintained. Additionally, the present review may assist in understanding certain aspects of cancer, and in making clinical decisions in a novel and more comprehensive manner.