HDAC inhibitor Vorinostat and BET inhibitor Plx51107 epigenetic agents' combined treatments exert a therapeutic approach upon acute myeloid leukemia cell model

The process of cancer initiation and development is regulated via the transcriptional expression of cells going under genomic and epigenetic changes. Targeting epigenetic readers, i.e., bromodomains (BRD) and post-translational modifications of nucleosomal histone proteins regulate gene expression in both cancerous and healthy cells. In this study, the new epigenetic agent BRD inhibitor PLX51107 and histone deacetylase (HDAC) inhibitor SAHA' s (Vorinostat) single/combined applications' reflections were analyzed in case of cell proliferation, cytotoxicity, apoptosis, cell cycle arrest, and finally target gene expression regulation upon both AML and healthy B-lymphocyte cells; HL60 and NCIBL2171, respectively; in vitro. Since mono treatments of either Vorinostat or Plx51107 regulated cellular responses such as growth, proliferation, apoptosis, and cell cycle arrest of tumor cells; their combination treatments exerted accelerated results. We detected that combined treatment of Plx51107 and Vorinostat strengthened effects detected upon leukemic cells for gaining more sensitization to the agents, decreasing cell proliferation, dramatically inducing apoptosis, and cell cycle arrest; thus regulating target gene expressions. We have shown for the first time that the newly analyzed BRD inhibitor Plx51107 could be a promising therapeutic approach for hematological malignancies and its mono or combined usage might support a rapid transition to clinical trials.Ege University Scientific Research Projects Coordinatorship [TGA-2019-20763]This study was funded by Ege University Scientific Research Projects Coordinatorship referred to as TGA-2019-20763

Suppression of STAT3 by chemically modified siRNAs increases the chemotherapeutic sensitivity of parental and cisplatin-resistant non-small cell lung cancer cells

WOS: 000334153000021PubMed ID: 24659656Purpose: Increased activation of the JAK-STAT signaling pathway is frequently observed in several primary cancers as well as cancer cell lines. Thus, targeting JAK-STAT pathway components by different molecular-biologic approaches in the search for new anticancer therapies has become widespread and resulted in encouraging outcomes. In this study, the effects of chemically modified anti-STAT3 small interfering (si)RNAs on cell viability, proliferation and apoptosis of parental and cisplatin resistant non-small cell lung cancer (NSCLC) cells were investigated with the aim to provide a new therapeutic strategy for overcoming cisplatin resistance in lung cancer. Methods: The parental NSCLC cell line Calu1 and its cisplatin-resistant subline CR-Calu1 were used to study the effects of STAT3 suppression with chemically modified anti-STAT3 siRNAs. STAT3 gene and protein expressions were analyzed by real-time (RT) quantitative (q) PCR and Western blot, respectively. Apoptosis was evaluated by Caspase-3 activity and cell death assays. Results: STAT3 messenger (m)RNA and protein expression were significantly increased in CR-Calu1 cells and suppressing its expression with specific siRNAs increased the rate of apoptosis through Caspase-3 activation. STAT3 suppression also significantly increased cisplatin sensitivity of Calu1 and CR-Calu1 cells after transfection with STAT3 siRNAs. Conclusions: NSCLC cells could be sensitized to cisplatin by targeting STAT3 with chemically modified siRNAs together, a fact which was accompanied with increased apoptosis

Methylprednisolone induces apoptosis by interacting with the JAK/STAT pathway in HL-60 and K-562 leukemic cells

WOS: 000305275000007PubMed ID: 22664047Objective: To determine the gene expression profiles of the JAK/STAT pathway members STAT3, STAT5A, STAT5B at both mRNA and protein levels in HL-60 and K-562 leukemia cells that were undergoing apoptosis following high-dose methylprednisolone (MP) treatment. Methods: HL-60 cells were treated with 0.1 mM MP and K-562 cells were treated with 0.4 mM MP according to their IC50 values. STAT3, STAT5A, and STAT5B mRNA relative expression levels were determined by qRT-PCR whereas the protein levels were detected via western-blot analysis and apoptosis was evaluated by Annexin V method. Results: A significant decrease was seen in STAT5A mRNA relative expression level at 48 hours of MP treatment (P < 0.05) both in HL-60 and K-562 cells. Other STATs showed a lower downregulation in their relative expressions at 48 hours at mRNA level for both of the cell lines. STAT proteins showed no expression change in K-562 cells in time course experiments but while STAT5A expression was downregulated; STAT5B showed an increase at 96 hours in HL-60 cells. Apoptosis was triggered by high-dose MP treatment that was evaluated by fluorescent microscopy. Conclusion: The JAK/STAT pathway components may play an important role in the apoptosis mechanism of leukemic cells under MP treatment in HL-60 and K-562 cells. Other pathways may also be involved with a post-translational modification seen in the HL-60 cell line, with both upregulation and downregulation of protein expression levels of STAT5B and STAT5A, respectively

Catechol-O-methyltransferase Val108/158Met gene and alcoholism in Turkish subjects

WOS: 000301993300014Aim: To determine if the functional Val108/158Met polymorphism causes a tendency toward alcohol addiction in Turkish cases. This polymorphism of the catechol-O-methyltransferase (COMT) gene has been associated with many psychiatric disorders, as well as with alcoholism. Materials and methods: The allele and genotype associations of the Val108/158Met polymorphism in 110 Turkish alcoholics and 330 healthy subjects were investigated, constituting our study and control groups, by polymerase chain reaction-restriction fragment length polymorphism. Results: Distribution of the Met/Met genotype was 16.4% to 20.6% and frequency of the Met allele was 36.8% to 39.5% in the study group compared to the control group. The results did not show any significant differences in the genotype distribution and allele frequencies of the polymorphism, neither between the study and the control groups (c(2) = 0.985, P = 0.611 and c(2) = 0.517, P = 0.472) nor between female (c(2) = 0.247, P = 0.884 and c(2) = 0.115, P = 0.735, respectively) and male (c(2) = 0.728, P = 0.695 and c(2) = 0.485, P = 0.486, respectively) alcoholics. The power of the study for genotype analysis was set at 79.1%. Conclusion: The present study shows that the polymorphic Met allele of the COMT polymorphism is not associated with alcoholism in Turkish cases; however, due to the lack of statistical power, this research should be evaluated again with an enlarged study group to confirm the possible association between the polymorphism and alcoholism