Scopus İndeksli Yayınlar Koleksiyonu

Permanent URI for this collectionhttps://hdl.handle.net/20.500.12573/395

Browse

Search Results

Now showing 1 - 3 of 3
  • Article
    Citation - WoS: 4
    Citation - Scopus: 4
    Differential in Vitro Anti-Leukemic Activity of Resveratrol Combined With Serine Palmitoyltransferase Inhibitor Myriocin in FMS-Like Tyrosine Kinase 3-Internal Tandem Duplication (FLT3-LTD) Carrying AML Cells
    (Springer, 2022-02-14) Ersoz, Nur Sebnem; Adan, Aysun
    Treatment of FMS-like tyrosine kinase 3 (FLT3)-internal tandem duplication (ITD) AML is restricted due to toxicity, drug resistance and relapse eventhough targeted therapies are clinically available. Resveratrol with its multi-targeted nature is a promising chemopreventive remaining limitedly studied in FLT3-ITD AML regarding to ceramide metabolism. Here, its cytotoxic, cytostatic and apoptotic effects are investigated in combination with serine palmitoyltransferase (SPT), the first enzyme of de novo pathway of ceramide production, inhibitor myriocin on MOLM-13 and MV4-11 cells. We assessed dose-dependent cell viability, flow cytometric cell death and cell cycle profiles of resveratrol in combination with myriocin by MTT assay, annexin-V/PI staining and PI staining respectively. Resveratrol's dose-dependent effect on SPT protein expression was also checked by western blot. Resveratrol decreased cell viability in a dose- dependent manner whereas myriocin did not affect cell proliferation effectively in both cell lines after 48h treatments. Although resveratrol induced both apoptosis and a significant S phase arrest in MV4-11 cells, it triggered apoptosis and non-significant S phase accumulation in MOLM-13 cells. Co-administrations reduced cell viability. Increased cytotoxic effect of co-treatments was further proved mechanistically through induction of apoptosis via phosphatidylserine relocalization. The cell cycle alteration in co-treatment was significant with an S phase arrest in MV4-11 cells, however, it was not effective on cell cycle progression of MOLM-13 cells. Resveratrol also increased SPT expression. Overall, modulation of SPT together with resveratrol might be the possible explanation for resveratrol's action. It could be an integrative medicine for FLT3-ITD AML after investigating its detailed mechanism of action in relation to de novo pathway of ceramide production.
  • Article
    Cytotoxic and Cytostatic Effects of Targeting mTOR and Hedgehog Pathways in Acute Myeloid Leukemia
    (Istanbul Univ, 2022-12-29) Cicek, Enes; Kucuktas, Fulya Mina; Yenigul, Munevver; Akcok, Emel Basak Gencer
    Objectives: Acute myeloid leukemia (AML) is a highly aggressive heterogeneous hematopoietic malignancy characterized by a rapid and abnormal proliferation of immature myeloid leukemia cells in the bone marrow and peripheral blood. Aberrant alterations in signal transduction pathways are strongly associated with the progression of AML. This study aimed to investigate cell viability and the cell cycle in AML cells by targeting the Hedgehog and mTOR signaling pathways with rapamycin and GANT61. Materials and Method: The antiproliferative effect of rapamycin and GANT61 was assessed by the MTT cell viability assay in two AML cell lines: CMK and MOLM-13. The effect of the inhibitors on cell-cycle distribution was determined using propidium iodide staining and measured with flow cytometry. Results: Rapamycin, an mTOR inhibitor, and GANT61, a Gli-1 inhibitor, decreased the cell proliferation of CMK and MOLM-13 cells. The IC20 values, which is the drug concentration that inhibits cell growth by 20%, were combined and administered to the cells. The results show the drugs to have a combinatorial inhibitory effect on CMK cells but not on MOLM-13 cells. In addition, the combination of drugs arrested the cells during the G0/G1 phase. Conclusion: This study suggests a novel combination therapy approach for AML via mTOR and Hedgehog signaling pathway inhibition using rapamycin and GANT61, respectively. It also suggest further studies be performed to reveal the mechanism of action.
  • Article
    Citation - Scopus: 1
    Glucosylceramide Synthase is a Novel Biomarker of Midostaurin-Induced Cytotoxicity in Non-Mutant FLT3 Positive Acute Myeloid Leukemia Cells
    (Istanbul University Press, 2021-12-03) Şahin, Hande Nur; Adan, Aysun
    Objective: Glucosylceramide (GC) synthesized by glucosylce-ramide synthase (GCS) favors cell survival and proliferation in many cancers. However, it’s role in Fms-like tyrosine kinase 3 (FLT3) non-mutant Acute Myeloid Leukemia (AML) pathogenesis is not clarified. Midostaurin, a multi-kinase inhibitor, clinically benefits FLT3-mutated AML, however, its clinical efficacy is under-estimat-ed in FLT3 non-mutant AML. This study aimed to investigate the efficacy of combination of midostaurin with GCS inhibitor in FLT3 AML cell carrying wild-type FLT3 and the underlying molecular mechanisms. Material and Method: Cytotoxic and cytostatic effects of mido-staurin, PDMP (GCS inhibitor) alone and in combination on THP1 cells were determined by MTT assay and flow cytometric propidi-um iodide (PI) staining, respectively. Calcusyn software was used to calculate combination indexes (CIs). GCS expression was checked by western blot. Results: Midostaurin downregulated GCS. Simultaneous inhibition of FLT3 and GCS resulted in suppression of cell proliferation as compared to untreated control. Combinations showed synergistic cytotoxic effects (CI<1). Co-treatments increased cell cycle population at G2/M phase. Conclusion: Inhibition of GCS enhances the efficacy of midostau-rin in FLT3 non-mutant AML, which could be a novel therapeutic approach to increase midostaurin’s limited usage in the clinic after detailed mechanistic studies. © 2023 Elsevier B.V., All rights reserved.