Isoform-specific regulation of NCAM1 gene expression in ischemic cardiomyopathy

Although ischemic cardiomyopathy (ICM) is the leading cause of chronic heart failure, one of the most common diseases overall, many aspects of the molecular pathogenesis of ICM still remain to be clarified. It has been We have previously shown that the neural cell adhesion molecule (NCAM1, CD56) is upregulated in ischemic cardiomyopathy by novel isoforms of the transcription factor RUNX1 (AML1) and, in the current study, we show that this upregulation is attributed exclusively to the NCAM1 isoform CD56-140kD. Moreover, we show that the upregulation of CD56-140kD has proapoptotic and antiproliferative effects on cardiomyocytes in vitro as well as inducing mitochondrial damage and reducing the capacity for Ca2+-uptake. As loss of cells and negative inotropy have previously been identified as major components in the development of ischemic cardiomyopathy, these data suggest that the upregulation of CD56-140kD may play a relevant role in the pathogenesis of ICM and therapeutic strategies targeting this molecule may prove to be valuable tools in the management of this very common and often fatal disease in the future.

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