Studies of the cell-specific processing of neuroendocrine peptides have shown that neuroendocrine cells occasionally fail to mature the biosynthetic precursors to bioactive peptides, or that they do so to a negligible extent only. Instead, inactive precursors and processing intermediates accumulate in the cells. Thus, the expression of genes encoding hormonal peptides is in certain cells and under certain conditions attenuated at the posttranslational level. The exact molecular mechanisms of posttranslational atenuation are still largely unknown. The review emphasizes that postttranslational attenuation may play a significant role during normal cell differentiation and in the carcinogenic transformation of cells. The existence of post-translational attenuation has significant biological and clinical implications
