Human CHUK blocking peptide

Background/Aims: Notch expression is not yet determined in hepatoblastoma. In this study the effect of chemotherapeutics (cisplatin, doxorubicin, cytosin arabinoside); differentiating agent (13 cis-retinoic acid) and apoptotic agents (5-aza-2'-deoxycytidine, arsenic trioxide) on notch expression in hepatoblastoma were evaluated. Methodology: After HepG2 cell line was cultured and the agents and their combinations were applied for 24 hour in pre-optimized 50% lethal doses, RNA isolation and cDNA converting, expression of 84 custom array genes of notch signaling pathway (SABiosciences, PAT059F-24) was determined by Real Time PCR. The methylation status of 6 genes that showed more than 5 fold changes compared with control group were explored by Methylation qPCR Assay. High expressed genes are HDAC1, NFKB1, CHUK, CDKN1A, and CBL. Low expressed genes are DLL1, CD44, FZD2, GLI1, IL17B, LMO2, NOTCH1, LOR, PAX5, PT-CRA, SH2D1A, and WISP1. The genes searched for methylation (DLL1, HEY1, DTX1, HDAC1, NOTCH2 and JAG1) were not found to be related with methylation. Results: The high expressed genes are related with cell proliferation. The main signaling genes that are closed to notch in signaling pathway are low expressed in hepatoblastoma. The agents do not show prominent effect of gene expression in many genes and methylation is not the reason of expression changes. The use of retinoic acid in the control of minimal residual disease of hepatoblastoma should be discussed. 5 aza "cytidin" the demethylating agent is not advised in treatment according to our results. Conclusion: Cisplatin as main chemotherapeutic agent treatment is shown to change gene expression levels in notch signalling pathway in hepatoblastoma.

The cardinal features of Ectrodactyly, Ectodermal dysplasia, Cleft lip/palate (EEC), and Ankyloblepharon-Ectodermal defects-Cleft lip/palate (AEC) syndromes are ectodermal dysplasia (ED), orofacial clefting, and limb anomalies. EEC and AEC are caused by heterozygous mutations in the transcription factor p63 encoded by TP63. Here, we report a patient with an EEC/AEC syndrome-like phenotype, including ankyloblepharon, ED, cleft palate, ectrodactyly, syndactyly, additional hypogammaglobulinemia, and growth delay. Neither pathogenic mutations in TP63 nor CNVs at the TP63 locus were identified. Exome sequencing revealed de novo heterozygous variants in CHUK(conserved helix-loop-helix ubiquitous kinase), PTGER4, and IFIT2. While the variant in PTGER4 might contribute to the immunodeficiency and growth delay, the variant in CHUK appeared to be most relevant for the EEC/AEC-like phenotype. CHUK is a direct target gene of p63 and encodes a component of the IKK complex that plays a key role in NF-kappa B pathway activation. The identified CHUK variant (g.101980394T>C; c.425A>G; p.His142Arg) is located in the kinase domain which is responsible for the phosphorylation activity of the protein. The variant may affect CHUK function and thus contribute to the disease phenotype in three ways: (1) the variant exhibits a dominant negative effect and results in an inactive IKK complex that affects the canonical NF-kappa B pathway; (2) it affects the feedback loop of the canonical and non-canonical NF-kappa B pathways that are CHUK kinase activity-dependent; and (3) it disrupts NF-kappa B independent epidermal development that is often p63-dependent. Therefore, we propose that the heterozygous CHUK variant is highly likely to be causative to the EEC/AEC-like and additional hypogammaglobulinemia phenotypes in the patient presented here.