Laminin, a major structural glycoprotein of the basement membranes, is an attachmentand survival factor for epithelial cells and can also promote the growth of epithelial cells. Laminin plays an important role in both the structural organization of basementmembranes and in the anchorage of cells. Laminin is a heterotrimeric extracellular matrixprotein consisting of 3 chains: alpha (LAMA1), beta (LAMB1), and gamma (LAMC1), formerlyA, B1, and B2, respectively. Several isoforms of each chain have been identified. Laminingamma 1 is the most ubiquitously expressed laminin subunit. Laminins are large heterotrimeric, noncollagenous glycoproteins composed of alpha, beta,and gamma chains. They are ubiquitously present in basement membrane (BM) along withentactin/nidogen (EN), collagen type IV (CIV), and large heparan sulfate proteoglycan(HSPG), which interact specifically with each other to form a continuous and regular BM. Alterations of BM integrity, from local discontinuities up to complete loss, are described inmany types of human and animal epithelial neoplasms.