2024-08

Hungarian Biochemical Society

Tyrosine Kinase Substrate 4 (TKS4) is a large scaffold protein in the EGFR signal transduction pathway that is involved in several cellular processes, such as motility, reactive oxygen species-dependent processes, embryonic development and cancer. It is also implicated in a rare developmental disorder, Frank–ter Haar syndrome. Deletion of TKS4 resulted in increased migration, invasion, and EMT-like processes while a decrease in proliferation in HCT116 colorectal carcinoma cells. In this study we demonstrated that enhancer of zeste homolog 2 (EZH2), the histone methyltransferase of the PRC2 is involved in these changes in TKS4 deficient cells. An elevation of local and global H3K27me3 levels were detected in the TKS4 KO cells, and inhibition of EZH2 activity reversed the effects of TKS4 KO, reducing the EMT-like features, migration speed, and invasion capacity of the cells while the decrease in proliferation become stronger. The broader effects of deletion of TKS4 on the gene expression pattern of colorectal carcinoma cells were explored by transcriptome sequencing of WT and TKS4 KO cells before and after treatment with DZNep; the EZH2 inhibitor. Several protein coding genes with altered mRNA levels were identified in the TKS4 KO cell line, as well as a set of long non-coding RNAs, whose expression levels were restored after EZH2 inhibition. In summary, our findings demonstrate a significant perturbation of gene expression upon the deletion of TKS4, suggesting the involvement of different signal transduction pathways over the well-known EGFR signalling.

2024-08

Hungarian Biochemical Society

KMT2D (also known MLL4) is a histone methyltransferase plays a critical role in regulating the epigenetic landscape of cells. Super-enhancers are large clusters of enhancers covering the long region of regulatory DNA and are densely occupied by transcription factors, active histone marks, and co-activators. According to our previous studies, KMT2D is capable of lncRNA binding and most recently KMT2D interacts with various RNA molecules, indicating a potential role in RNA processing

2023-03

Hungarian Life Sciences Conference

Tks4 is a large scaffold protein in the EGFR signal transduction pathway that is involved in several cellular processes, such as motility, reactive oxygen species-dependent processes, and embryonic development. It is also implicated in a rare developmental disorder, Frank–ter Haar syndrome. Deletion of Tks4 resulted in the increased migration, invasion, and induction of epithelial to mesenchymal transition (EMT)-like processes in HCT116 colorectal carcinoma cells. In this study we demonstrated that the Enhancer of zeste homolog 2 (EZH2), the histone methyltransferase of the Polycomb Repressive complex 2 (PRC2) is involved in these changes in Tks4 deficient cells. We detected an elevation of global H3K27me3 levels in the Tks4 KO cells, and inhibition of EZH2 activity reversed the effects of Tks4 knockout, reducing the EMT-like features, migration speed, and invasion capacity of the cells. Also, we explored the broader effects of deletion of Tks4 on the gene expression pattern of colorectal carcinoma cells by transcriptome sequencing of wild-type and Tks4 knockout (KO) cells before and after treatment with DZNep; the EZH2 inhibitor. We identified several protein coding genes with altered mRNA levels in the Tks4 KO cell line, as well as a set of long non-coding RNAs, whose expression levels were restored after EZH2 inhibition. In summary, our findings demonstrate a significant perturbation of gene expression upon the deletion of Tks4, suggesting the involvement of different signal transduction pathways over the well-known EGFR signaling.

2021-11

Hungarian Life Sciences Conference

Epithelial-mesenchymal transition (EMT) is a process where the epithelial cells acquire mesenchymal properties by repressing cell–cell junction and losing cell-cell interactions and gaining a more migratory phenotype. The first step in the metastasis formation of cancer is EMT. EMT is involved in different physiological and pathological processes such as embryogenesis, inflammation, wound healing, and cancer metastasis. Various factors have been involved in the regulation of EMT, these include different transcription factors (TFs), several small and long non-coding RNAs, epigenetic modulators and exogenous inducers [1]. Enhancer of zeste homolog 2 (Ezh2) is a histone lysine methyltransferase responsible for the activity of Polycomb Repressive Complex 2 (PRC2). Ezh2 is responsible for the maintenance of the trimethylated lysine 27 on histone H3 (H3K27me3) [2]. Tyrosine kinase substate 4 (Tks4) belongs to the family of scaffold proteins that is tyrosine phosphorylated by EGFR pathway through Src kinase. It is a protein product of SH3PXD2B gene. Tks4 is characterized by a PX domain and four Src homology 3 domains [3]. Tks4 is closely related to Src substrate adaptor proteins that are required for podosome formation, cancer cell invasion and tumor growth [4]. In humans, the Tks4 deficiency is responsible for the development of Frank-ter Haar syndrome. According to our previous study, the absence of Tks4 induces EMT like changes [5]. In this study, we demonstrated that the EZH2 is involved in the EMT like change in Tks4 deficient cells.

2021-11

Hungarian Life Sciences Conference

Proteins with large intrinsically disordered regions are the second most common drivers of liquid phase separation, and the lysine methyl transferase KMT2D (also known as mixed lineage leukemia 4; MLL4) contains intrinsically disordered regions up to 70% of its full length. KMT2 proteins are responsible for the mono-and di-methylation of histones at enhancers, and tri-methylation of histone H3 lysine 4 (H3K4) at active promoters. According to our previous studies, KMT2D is capable of lncRNA binding, but the molecular background and the physiological relevance of this binding are obscure. As some lncRNAs play their role as molecular scaffolds to enroll chromatin regulators in the formation of membraneless biomolecular condensates and allocate their enzymatic activities to proper locations in the genome to influence the expression of target gene, it is possible that the lncRNA binding of KMT2D is important in its regulation and targeting.

2015-10

XIV. ULUSAL TIBBİ BİYOLOJİ VE GENETİK KONGRESİ

Long noncoding RNA (lncRNA)’lar son yıllarda tüm genom ve transkriptom sekanslama yöntemlerinin gelişmesi ile bilim dünyasında ilgi odağı haline gelmişlerdir. Son yıllarda yapılan çalışmalar ile lncRNA’ların birçok biyolojik fonksiyonu ortaya konmuş ve bu RNA moleküllerinin deregülasyonu kanser başta olmak üzere birçok kompleks hastalık ile ilişkilendirilmiştir. Long intergenic non-protein coding RNA 663 (LINC00663) 19. Kromozomda yerleşiktir ve bu zamana kadar papiller tiroid karsinom haricinde hiçbir patoloji ile ilişkilendirilmemiştir. Bu çalışmada LINC00663’ün farklı insan dokularda ve aynı zamanda farklı kanser hücre hatlarında ekspresyon profilinin belirlenmesi amaçlanmıştır.

2014-09

TIBBI GENETİK KONGRESİ

Long noncoding RNA (lncRNA)’lar son yıllarda tüm genom ve transkriptom sekanslama yöntemlerinin gelişmesi ile bilim dünyasında ilgi odağı haline gelmişlerdir. Son yıllarda yapılan çalışmalar ile lncRNA’ların birçok biyolojik fonksiyonu ortaya konmuş ve bu RNA moleküllerinin deregülasyonu kanser başta olmak üzere birçok kompleks hastalık ile ilişkilendirilmiştir. Long intergenic non-protein coding RNA 663 (LINC00663) 19. Kromozomda yerleşiktir ve bu zamana kadar papiller tiroid karsinom haricinde hiçbir patoloji ile ilişkilendirilmemiştir. Bu çalışmada LINC00663’ün farklı insan dokularda ve aynı zamanda farklı kanser hücre hatlarında ekspresyon profilinin belirlenmesi amaçlanmıştır.