Hormonal activation of adenylate cyclase in mouse melanoma metastatic variants

✍ Scribed by R. M. Niles; J. S. Makarski

• Publisher: John Wiley and Sons
• Year: 1978
• Tongue: English
• Weight: 393 KB
• Volume: 96
• Category: Article
• ISSN: 0021-9541
• DOI: 10.1002/jcp.1040960311

✦ Synopsis

The ability of melanocyte stimulating hormone (MSH), adrenocorticotropic hormone (ACTH), and prostaglandin El (PGE,) to stimulate the accumulation of cyclic AMP was examined in intact mouse melanoma cells of varying metastatic potential. Fl cells (low metastatic potential) had significantly greater cyclic AMP levels in response to all three hormones than F5 (intermediate metastatic potential) and Fl0 (high metastatic potential) cells. The ranking of the response was as follows: MSH, F, > F5> Flo, ACTH, F, > F5> Flo, PGE, Fl > Flo> F5. In contrast to the above, the degree of hormonal stimulation of adenylate cyclase in broken cell preparations was virtually identical in all three melanoma cell lines. Control enzyme activity was depressed in both F5 and F,, relative to F,. The conflicting results between studies of intact vs. broken cell preparations could not be explained by increased cyclic AMP phosphodiesterase activity in F5 and Flo cells. We conclude that as the melanoma cells increase in metastatic potential, there is a significant loss in the ability of their cyclic AMP system to respond appropriately to hormonal stimuli.