TY - JOUR T1 - Suramin is a potent inhibitor of calcemic hormone- and growth factor-induced bone resorption in vitro. JF - Journal of Pharmacology and Experimental Therapeutics JO - J Pharmacol Exp Ther SP - 579 LP - 583 VL - 264 IS - 2 AU - K H Farsoudi AU - P Pietschmann AU - H S Cross AU - M Peterlik Y1 - 1993/02/01 UR - http://jpet.aspetjournals.org/content/264/2/579.abstract N2 - Suramin, a polysulfonated naphtylurea compound that has been used in the past for treatment of trypanosomiasis and onchocerciasis, is also an effective antitumor agent. Its marked antiproliferative potential probably resides in the ability of the drug to interfere with various growth factor signaling mechanisms. We were interested in whether suramin could also interact with signal transduction in bone cells, leading to osteoclast proliferation and, consequently, bone resorption. Utilizing organ-cultured neonatal mouse calvaria, we studied the effect of suramin on bone resorption induced by, for example, parathyroid hormone, 1,25-dihydroxycholecalciferol, epidermal growth factor or thrombin. In the 1 to 100 microM concentration range, in which no toxic effect on bone cells was observed, suramin effectively suppressed bone resorption regardless of whether it was mediated by endogenous prostaglandin production or induced by parathyroid hormone (Ki = 70 microM), 1,25-dihydroxycholecalciferol (Ki = 70 microM), epidermal growth factor (Ki = 5 microM) or thrombin (Ki = 5 microM). The profound inhibitory effect of suramin on various bone resorptive processes around 100 microM, which is regarded as the minimally effective concentration for successful anticancer treatment, could be exploited for the treatment particularly of tumors associated with hypercalcemia. ER -