In fact, URI a member of the prefoldins, functions as a molecular scaffolding protein that assembles a multi-protein molecular complex that has functions in transcription and post-translational modification. It is interesting that the cardiac cofactors of Art27 identified here are also well known to interact with one another and other crucial cardiac transcription factors. Our findings suggest that it is possible Art27 participates in this interactive network, perhaps in a similar way to URI as a molecular scaffolding protein. Our experiments identified Art27 as an intrinsic transcriptional repressor whether it was artificially tethered to the promoter by a GAL-DBD fusion or whether it was in concert with other DNAbinding cardiac transcription factors. In contrast to this, other research identified Art27 as a transcriptional activator, as a cofactor to the Androgen Receptor in prostate cancer cell lines. However in these prostate cancer cells when Art27 expression was repressed, Androgen Receptor target genes were up-regulated indicating a native Art27 repressive role. Art27 is likely to have a tissue specific or gene specific regulatory mechanism. This is not uncommon; other examples of this are apparent in cardiac gene regulation where Nkx2.5 generally activates genes involved in cardiomyocyte differentiation while it represses genes involved in progenitor proliferation. Nevertheless, when present with cardiac transcriptional activators, Art27 is seen to dramatically down-regulate the cardiac promoters. The transcriptional cofactors of Art27 identified in this study have roles in cardiac development and in the adult heart, regulating cardiac hypertrophic remodelling. Similarly, we have identified Art27 as a GATA-1 cofactor, which is a prominent regulator of haematopoiesis. Future work is required to ascertain the biological relevance of Art27 as a transcriptional co-repressor in cardiac and other tissues. As an initial step, here we report microarray analysis of P19CL6-Mlc2vGFP cardiomyocytes in which Art27 was knockdown by siRNA. The data show upregulation of important cardiac genes. Sfrp4 is of particular interest since it is involved, together with Wnt11, in non-canonical Wnt signalling which is in turn critical for cardiogenesis. Moreover, Wnt11 is a direct target of GATA4 and GATA6 and it is functionally active downstream of GATA4 and GATA6, thus implicating Art27 in the regulation of endogenous GATA4 target genes. Esophageal squamous cell carcinoma accounts for nearly 90% of all esophageal cancers and is the fourth leading cause of cancer death in China. Despite significant diagnostic and therapeutic advances, the 5-year overall survival rate for ESCC is still less than 25%, due mainly to distant metastasis and limited therapeutic options at initial diagnosis. In sharp contrast, the 5-year survival rate for ESCC patients at early stages is more than 90%.