Effect of dibutyryl cyclic AMP on morphologic features and biologic markers of a human salivary gland adenocarcinoma cell line in culture.

Dibutyryl cyclic AMP (dB-cAMP) has marked effects on the growth, morphologic features, and biologic markers of a human salivary gland adenocarcinoma cell line in culture. A cell line with ultrastructure and biologic markers specific to the intercalated duct cells of human salivary glands was cultivated in the presence of dB-cAMP. Major alterations, such as process formation and expression of myofilaments and oxytocin receptor in addition to myosin and S-100 protein, were observed in those cells with a phenotype similar to myoepithelial cells. Both the anchorage-independent and anchorage-dependent growths were markedly suppressed in the presence of dB-cAMP. After the removal of dB-cAMP from the culture, the treated cells returned rapidly to the phenotype of the untreated cells. These findings indicate that reversible differentiation into the myoepithelial cells of a human salivary gland adenocarcinoma cell line occurs in growth medium containing dB-cAMP.