The existence of integral membrane components that are involved in cell-substratum adhesion has been postulated. Using an immunochemical approach developed in this laboratory, we provide further evidence for the role in cell-substratum adhesion of integral membrane glycoproteins within a molecular weight region of 120,000-140,000. Sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis of material enriched approximately 100-fold in adhesion-related components revealed the 120,000-140,000 Mr glycoproteins in an adherent hamster melanoma cell line. These glycoproteins are greatly reduced in a nonadherent variant. Induction of adhesion in these cells by exposure to BudR is accompanied by re-expression of the surface adhesion antigens.