Dimethyl sulfoxide affects colony morphology on agar and alters distribution of glycosaminoglycans and fibronectin

Abstract

We have found striking changes in the morphology of colonies of Chinese hamster ovary cells grown on agar containing low doses of dimethyl sulfoxide. Effects on morphology of cells grown on plastic at the same dimethyl sulfoxide concentrations were not as pronounced. Computer-assisted analysis of darkfield photographs of growing colonies proved very useful in measuring the magnitude of morphological changes at various doses. A large decrease in total cell-bound and released glycosaminoglycans (GAGs) was observed in the presence of dimethyl sulfoxide by measuring incorporation of radiolabeled precursors into cetylpyridinium chloride-precipitable GAGs in Chinese hamster ovary cells. By contrast, dimethyl sulfoxide was found to cause an increase in the network of fibronectin (the large external transformation-sensitive protein) at the cell surface. These observations demonstrate the association of GAGs and fibronectin in processes affecting the three-dimensional growth patterns of aggregates of mammalian cells and also demonstrate the sensitivity of agargrown colonies as model systems for quantitatively measuring the morphological changes induced by exogenous agents such as drugs, hormones, growth factors, mutagens, and carcinogens. These findings might be relevant to the study and treatment of the important class of genetic diseases called mucopolysaccharidoses which result in mental, skeletal, and ocular defects as a consequence of GAG accumulation.