Caspase-3 activation in human melanoma A375 cell line by a novel selective sigma-2 agonist

Two novel 8-azabicyclo[3.2.1]octan-3-ol derivatives, 11a and 11b, with high affinity for sigma-2 receptors and a very good sigma-1/sigma-2 selectivity ratio were synthesized. In comparison with several well established sigma-2 selective ligands, 11 b showed a very low sigma-1 receptor affinity. Functional assays demonstrated that 11b acts as an agonist and in A-375 human melanoma cell line is able to lower levels of procaspase-3, thus confirming a potential major role for sigma-2 pure agonists in the treatment of rapid proliferating melanoma cells.