Fluorizoline is a new synthetic molecule that induces apoptosis by selectively targeting prohibitins. In the study herein, the pro-apoptotic effect of fluorizoline was assessed in 34 primary samples from patients with chronic lymphocytic leukemia. Fluorizoline induced apoptosis in chronic lymphocytic leukemia cells at concentrations in the low micromolar range.
View Article and Find Full Text PDFWe previously described diaryl trifluorothiazoline compound 1a (hereafter referred to as fluorizoline) as a first-in-class small molecule that induces p53-independent apoptosis in a wide range of tumor cell lines. Fluorizoline directly binds to prohibitin 1 and 2 (PHBs), two proteins involved in the regulation of several cellular processes, including apoptosis. Here we demonstrate that fluorizoline-induced apoptosis is mediated by PHBs, as cells depleted of these proteins are highly resistant to fluorizoline treatment.
View Article and Find Full Text PDFA new class of small molecules, with an unprecedented trifluorothiazoline scaffold, were synthesized and their pro-apoptotic activity was evaluated. With an EC50 in the low micromolar range, these compounds proved to be potent inducers of apoptosis in a broad spectrum of tumor cell lines, regardless of the functional status of p53. Fast structure-activity relationship studies allowed the preparation of the strongest apoptosis-inducing candidate.
View Article and Find Full Text PDF5-Aminoimidazole-4-carboxamide (AICA) riboside (AICAR) is a nucleoside analogue that is phosphorylated to 5-amino-4-imidazolecarboxamide ribotide (ZMP), which acts as an AMP mimetic and activates AMP-activated protein kinase (AMPK). It has been recently described that AICAR triggers apoptosis in chronic lymphocytic leukemia (CLL) cells, and its mechanism of action is independent of AMPK as well as p53. AICAR-mediated upregulation of the BH3-only proteins BIM and NOXA correlates with apoptosis induction in CLL cells.
View Article and Find Full Text PDFAim: To analyze the methylation status of 35 tumor suppressor genes using methylation-specific multiplex ligation-dependent probe amplification (MS-MLPA) in chronic lymphocytic leukemia (CLL).
Materials & Methods: The DNA of 37 samples from patients with CLL, six healthy donors, and Jurkat and Ramos cell lines was analyzed by MS-MLPA.
Results: Our results confirm that hypermethylation is a common and not randomly distributed event in CLL, and some genes, such as WT1, CDH13, IGSF4/TSLC1, GATA5, DAPK1 and RARB, are hypermethylated in more than 25% of the analyzed samples.
Glucocorticoids (GC) induce cell cycle arrest and apoptosis in different cell types and therefore are widely used to treat a variety of diseases including autoimmune disorders and cancer. This effect is mediated by the GC receptor (GR), a ligand-activated transcription factor that translocates into the nucleus where it modulates transcription of target genes in a promoter-specific manner. Glycogen synthase kinase-3 (GSK3) regulates GR response by genomic and nongenomic mechanisms, although the specific role of each isoform is not well defined.
View Article and Find Full Text PDFHistone deacetylases (HDACs) play a key role in the regulation of acetylation status not only of histones but also of many other non-histone proteins involved in cell cycle regulation, differentiation or apoptosis. Therefore, histone deacetylase inhibitors (HDACi) have emerged as promising anticancer agents. Herein, we report the characterization of apoptosis in B-cell chronic lymphocytic leukemia (CLL) induced by two HDACi, Kendine 92 and SAHA.
View Article and Find Full Text PDF5-Aminoimidazole-4-carboxamide riboside or acadesine (AICAR) induces apoptosis in chronic lymphocytic leukemia (CLL) cells. A clinical study of AICAR is currently being performed in patients with this disease. Here, we have analyzed the mechanisms involved in AICAR-induced apoptosis in CLL cells in which it activates its only well-known molecular target, adenosine monophosphate-activated protein kinase (AMPK).
View Article and Find Full Text PDFAspirin and other non-steroidal anti-inflammatory drugs induce apoptosis in most cell types. In this study we examined the mechanism of aspirin-induced apoptosis in human leukemia cells. We analyzed the role of nuclear factor-kappaB (NF-kappaB) and mitogen-activated protein kinases (MAPKs) pathways.
View Article and Find Full Text PDFBackground: The phosphatidylinositol-3-kinase/Akt pathway has been described to be critical in the survival of chronic lymphocytic leukemia cells. In this study we analyzed the effect of two selective chemical inhibitors of Akt (Akti-1/2 and A-443654) on the survival of chronic lymphocytic leukemia cells.
Design And Methods: Using cytometry we studied the cytotoxic effects of Akt inhibitors on peripheral B and T lymphocytes from patients with chronic lymphocytic leukemia and from healthy donors.
Background And Objectives: The potential anticancer agent 1-(2-chlorophenyl-N-methylpropyl)-3-isoquinolinecarboxamide (PK11195), a translocator protein (18KDa) (TSPO) ligand, facilitates the induction of cell death by a variety of cytotoxic and chemotherapeutic agents. Primary chronic lymphocytic leukemia (CLL) cells overexpress TSPO. The aim of this study was to examine the effects of PK11195 on CLL cells.
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