scholarly journals The Alkylating Histone Deacetylase Inhibitor Fusion Molecule Edo-S101 Displays Full Bi-Functional Properties in Preclinical Models of Hematological Malignancies

Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 2100-2100 ◽  
Author(s):  
Ana Alicia López-Iglesias ◽  
Laura San-Segundo ◽  
Lorena González-Méndez ◽  
Susana Hernández-García ◽  
Daniel Primo ◽  
...  
Keyword(s):  
Single Dose ◽  
Cell Line ◽  
Cell Lines ◽  
Hematological Malignancies ◽  
Parp Cleavage ◽  
Hdac Inhibition ◽  
Histone 3 ◽  
Xenograft Models

Abstract Background Alkylating histone deacetylase inhibitors (HDACi) enhance the anticancer efficacy of alkylators by increasing chromatin accessibility and also down regulating DNA repair. EDO-S101 is a first-in-class fusion molecule that combines DNA damaging effect of bendamustine with the pan-HDACi vorinostat. Objectives To study the bi-functional properties of EDO-S101 as an alkylating agent and a pan-HDACi in various in vitro and in vivo xenograft models of hematological malignancies. Methods In vitro inhibition of HDAC Class I and II enzymes by EDO-S101 and vorinostat was tested using an recombinant human enzymatic assay (BPS Bioscience, Enzo Life Science) and in vivo in rat peripheral blood mononuclear cells (PBMCs). The degree of inhibition was measured 1 hour following a single dose of 10–50 mg/kg i.v. and duration of inhibition over 24 hours after a single i.v. dose of EDO-S101 of 25 mg/kg. HDAC inhibition, alkylation and apoptotic activity were evaluated in vitro in myeloid (HL60 AML cell line) and lymphoid cell lines, including Daudi Burkitt’s lymphoma (BL) and a panel of 6 MM cell lines (MM1S, MM1R, RPMI-8226, RPMI-LR5, U266, U266-LR7). In vivo intra-tumor effects were analyzed after short courses of treatment with EDO-S101 in MM1S human plasmacytoma (PC) and BL xenograft models. Changes in pathway activation, protein expression and activities influencing the cell cycle were measured by Western blot and immunohistochemistry. Anti-tumor activity in vitro was measured by MTT and in vivo using a caliper to assess tumor size at regular intervals. Results In vitro, EDO-S101’s pan-HDACi activity, at nanomolar concentrations in Class I and II recombinant enzymes, was similar to vorinostat. In vivo, in intact rat PBMCs, HDAC inhibition was maximal at 1 hour after a single dose of 10 mg/kg i.v.–the dose where antitumor activity starts. HDAC inhibition did not increase with doses up to 50 mg/kg, recovery began within 3 hours and was nearly complete at 16 hours. In the AML HL60 cell line in vitro, hyperacetylation of lysine residues K9, K14, K23 and K56 on histone 3 was found after exposure to 2–4 µM of EDO-S101. Histone 3 and 4 hyperacetylation was also demonstrated in MM cell lines at 1–5 µM concentrations. In xenograft models of human plasmacytoma and BL, EDO-S101 induced histone 3 hyperacetylation, indicating an HDACi effect in vivo. Alkylating activity was demonstrated in vitro in HL60 and MM cell lines by DNA cross-linking and double strand break formation in the comet assay by immunofluorescence. In vivo, in xenograft models of human plasmacytoma (60 mg/kg d 1, 8, 15) and BL (40 and 80mg/kg d1) exposure to EDO-S101 caused a strong DNA-repair response shown by activation of pH2AX and p53 (PC and BL) followed by an increase of DNA damage check point proteins pCHK1 (PC) and even more prominent pCHK2 (PC and BL). The kinetics of this effect, studied in vivo in BL tumors, showed that the pH2AX response fell at Day 8 after dosing while the p53 response lasted, particularly in the group treated with 80mg/kg. In Daudi-bearing mice tumors, p-ATR was completely suppressed at Day 8 after treatment, which was not clear in the PC tumors. EDO-S101 triggered apoptosis in vitro and in vivo, resulting in strong antitumor activity in HL60, Daudi and the panel of six MM cell lines. Initial in vitro experiments in HL60 cells showed an activation of the intrinsic pathway of apoptosis with cleavage of caspases 3, 9 and PARP and a marked reduction of anti-apoptotic proteins XIAP and Mcl-1. In the MM cell line, MM1S activation of the intrinsic and extrinsic pathways of apoptosis (C 8, 9, 3, 7 and PARP cleavage) was seen with a loss of mitochondrial membrane potential by DiOC6. Tumors of human plasmacytoma and BL in vivo were rapidly shrinking or completely eradicated after i.v. administration of EDO-S101. A decrease in proliferation (Ki67) and slight PARP cleavage was found in the tumor tissue (PC), and evidence of activation of apoptosis by cleavage of caspases 7 and 9 at Day 4 and caspase 8 and PARP at Day 8 after treatment in BL tumors. The level of caspase 3, different to MM, remained unchanged. Importantly, EDO-S101 induced a rapid and dose-dependent strong decrease of XIAP and Mcl-1 which lasted until Day 8. Conclusions This study demonstrates the bi-functional mechanism of ED0-S101 in both myeloid and lymphoid hematological malignancies. The data support the clinical investigation of EDO-S101 in treating hematological malignancies. Disclosures Ocio: Mundipharma: Honoraria, Research Funding. Mehrling:Mundipharma: Employment.

The Multi-Targeted Receptor Tyrosine Kinase Inhibitor, ABT-869, Induces Apoptosis of AML Cells Both In Vitro and In Vivo.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 616-616 ◽  
Author(s):  
Deepa B. Shankar ◽  
Jenny C. Chang ◽  
Bertrand Parcells ◽  
Salemiz Sandoval ◽  
Junling Li ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Tyrosine Kinase ◽  
Cell Line ◽  
Progenitor Cells ◽  
Cell Lines ◽  
Receptor Tyrosine Kinase ◽  
Scid Mice ◽  
Parp Cleavage

Abstract Children with acute myeloid leukemia (AML) have less than 60% overall survival despite aggressive chemotherapy and bone marrow transplantation. Only one third of the adult patients diagnosed with AML will be cured. AML blast cells from up to 30% of patients express a constitutively active receptor tyrosine kinase, FLT3-ITD, which contains an internal tandem duplication in the juxtamembrane domain. Patients with FLT3-ITD have a worse prognosis. ABT-869 is a novel multi-targeted small molecule inhibitor of receptor tyrosine kinases and is a potent inhibitor of FLT3, c-Kit, and all members of the VEGF and PDGF receptor families. To determine the effects of ABT-896 on AML cells, we treated AML cell lines, primary cells, and tumors in xenograft models with varying concentrations of the drug. In vitro viability assays showed that ABT-869 inhibited the growth of two different cell lines, MV-4-11 (human AML cell line that expresses FLT3-ITD) and BAF3-ITD (murine B-cell line stably transfected with the FLT3-ITD) at an IC50 of 10nM. ABT-869 was also effective against another mutation of FLT3, D835V, but at higher concentrations (IC50 of 100nM). Phosphorylation of FLT3 and activation of downstream signaling molecules, STAT5 and ERK, were inhibited by ABT-869 in a concentration-dependent manner. Cells were also stained with Annexin V-FITC and Propidium Iodide, and analyzed using FACS. ABT-869 induced apoptosis, caspase-3 activation, and PARP cleavage after 48 hours. To examine the in vitro effects of ABT-869 on normal hematopoietic progenitor cells, we performed methylcellulose-based colony assays with human bone marrow. No significant difference was observed in the number and type of colonies formed using BM cells treated with ABT-869 or control, up to a concentration of 1 micromolar. These results suggest that ABT-869 is not toxic to normal bone marrow progenitor cells at concentrations that are effective against AML cells. To examine the effects of ABT-869 in vivo, we treated SCID mice injected with MV-4-11, Baf3-ITD, Baf3-D835V, or Baf3-WT cells, with oral preparations of ABT-869. Complete regression of MV-4-11 tumors was observed in mice treated with ABT-869 at 20 and 40 mg/kg/day. No adverse effects were detected in the peripheral blood counts, bone marrow, spleen or liver. Histology of the tumors from the control-treated group showed a high degree of proliferation by Ki-67 staining, increased mitotic figures, and a well-defined tumor mass. In contrast, the tumors from mice treated with ABT-869 showed a number of apoptotic bodies by TUNEL staining and the presence of reactive, inflammatory cells. Interestingly, we also observed that mice that received ABT-869 the day after injection of AML cells remained tumor-free for over 2 months in contrast to the mice receiving the vehicle alone. Inhibition of FLT3 phosphorylation was demonstrated in the tumors from mice treated with ABT-869. We are evaluating the activity of ABT-869 treatment of SCID mice injected with Baf3-ITD, Baf3-D835V, or Baf3-WT cells. NOD-SCID mouse models are currently being used to analyze the effects of ABT-869 on primary AML cells in vivo. Our preclinical studies demonstrate that ABT-869 is effective and nontoxic, and provide rationale for the treatment and prevention of relapse in AML patients.

scholarly journals Chemical Genomics Reveals JAK STAT Activation As a Mechanism of Resistance to HDAC Inhibitors in B Cell Lymphomas

Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 271-271
Author(s):  
Matthew S. McKinney ◽  
Anne W Beaven ◽  
Andrea Moffitt ◽  
Jason Landon Smith ◽  
Eric Lock ◽  
...  
Keyword(s):  
Gene Expression ◽  
B Cell ◽  
Cell Line ◽  
Cell Lines ◽  
Hdac Inhibitors ◽  
Resistant Cell ◽  
Hdac Inhibition ◽  
Stat Pathway

Abstract Background: HDAC inhibitors (HDACi) are being investigated as treatment for relapsed/refractory non Hodgkin lymphoma (NHL) and other cancers. However, the mechanisms underlying sensitivity and resistance to HDAC inhibition in lymphomas have not been fully characterized. We probed the cellular and molecular response to HDACi in vitro and in vivo in order to determine factors that dictate the response to HDACi and to enable design of approaches to incorporate HDACi into novel combination therapeutics. Methods: High-throughput cytotoxicity screening was performed using two different HDAC inhibitors, LBH589 (panobinostat) and SAHA (vorinostat) in 52 lymphoid cell lines characterized through RNA-seq and microarray gene expression profiling. This screen revealed a greater than 50-fold range in concentration needed to induce cytotoxicity for the 2 different HDAC inhibitors and there was moderate correlation between the 2 compounds in this panel (Pearson correlation r = 0.76, p < 0.01). By pairing this chemosensitivity data with gene expression profiles of the screened cell lines, we developed a gene expression classifier for LBH589 that identified resistant and sensitive cell line groups. This predictor was applied to B-cell NHL cell lines tested with LBH589 in the Cancer Cell Line Encyclopedia (CCLE) and we found that the sensitive and resistant cell line groups distinguished by this method differed more than 5-fold in IC50 (0.021 vs. 1.24 nM, P < 0.01 by Wilcoxon rank sum), thus validating the ability of this approach to distinguish HDACi resistant cell lines. We further initiated a clinical trial of LBH589 in relapsed/refractory diffuse large B cell lymphoma patients combined with RNAseq profiling of their tumors prior to embarking on treatment. We treated nine patients with LBH589, and application of our response predictor to scaled RNAseq gene expression data revealed 4 predicted responders and 5 predicted non-responders. Two of the predicted responders had a clinical response to LBH589, whereas none of the predicted non-responders had a clinical response, thus our classifier was able to identify all of the LBH589-responsive patients from this cohort (P = 0.08 by Fisher's exact test). Analysis of differentially expressed molecular pathways in HDACi sensitive and resistant samples by gene set enrichment revealed the JAK-STAT pathway as the most differentially expressed pathway associated with HDACi resistance (at P < 0.001 and FDR < 0.20). We further identified a number of distinct mutations including STAT3, SOCS1 and JAK1 that were associated with activation of the JAK-STAT pathway by gene expression signatures and the LBH589 response signature in DLBCL cell lines and patient samples by analysis of RNA-seq data. Phosphoprotein analysis by Western blot and Sis-inducible-element (SIE) luciferase reporter assays were used to confirm JAK-STAT activation in these samples and we found that overexpression of STAT3 Src-homology domain mutations activated JAK-STAT3 signaling in isogenic cell lines and fostered resistance to LBH589 in vitro. Conversely, using in vivo DLBCL xenograft models, we found that combining JAK-STAT and HDAC inhibition by treatment with LBH589 and ruxolitinib resulted in synergistic reduction of tumor cell viability and tumor growth with tolerable toxicity in mice. Conclusions: Sustained JAK-STAT activation appears to mediate resistance to HDAC inhibition in DLBCL and other NHLs and several recurrent genetic lesions drive JAK-STAT activation in these diseases. This process can be overcome by JAK 1/2 inhibition with ruxolitinib and these findings demonstrate a role for combination therapy with HDAC inhibitors and small molecules targeting the JAK-STAT pathway in lymphoid malignancies. Disclosures No relevant conflicts of interest to declare.

In Vitro and In Vivo Inhibition of P-Glycoprotein (ABCB1) by a Novel Non-Substrate Compound: HG-829

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 3986-3986
Author(s):  
Gisela Caceres ◽  
Robert W Robey ◽  
Lubomir Sokol ◽  
Kathy Rocha McGraw ◽  
William J Fulp ◽  
...  
Keyword(s):  
Cell Line ◽  
Cell Lines ◽  
Proliferation Assay ◽  
Hek 293 ◽  
P Glycoprotein ◽  
Wide Range ◽  
Xenograft Models ◽  
Substrate Inhibitor

Abstract Abstract 3986 Background: P-glycoprotein (P-gp or ABCB1) is a common cause of multidrug resistance (MDR) in cancer and leukemia that serves to extrude amphipathic drugs from the plasma membrane. P-gp is an ATP-binding cassette (ABC) transporter that exports a wide range of anti-neoplastics that are structurally or functionally unrelated. The vast majority of P-gp inhibitors tested clinically act as competitive export channel inhibitors to promote antineoplastic retention. We investigated the in vitro and in vivo effects of a novel substituted quinoline P-gp modulator, HG-829, in MDR cell lines and xenograft models. Methods: In vitro activity of HG-829 was evaluated in the K562-daunomycin-selected (K562-R) cell line and the ABCB1-transfected human embryonic kidney-293 cell line (HEK-293-B1) using a variety of P-gp substrates (daunomycin, doxorubicin, taxol, etoposide, vincristine) in a 72h MTT proliferation assay, and results compared to the effects of cyclosporine-A (CsA). Rhodamine 123 export and retention was assessed by flow cytometry. Flank injections of K562-R and parental K562-S cells in female SCID beige mice were performed for xenograft models. ANOVA and Turkey's multiple comparison tests were used to determine significant differences between groups in the proliferation assay and xenograft studies. Differences in rhodamine intracellular retention and efflux were assessed by Student's t-test. Results: Treatment with HG-829 at 0.5uM and 1uM completely reversed resistance to each of the antineoplastics studied in both the K562-R and HEK-293-B1 cell lines, but did not sensitize parental cells. HG-829 sensitized K562-R cells to daunomycin 57-fold and 97-fold at concentrations of 0.5uM and 1uM, respectively (p<0.01). Similarly, resistance to taxol (HG-829 0.5uM p<0.01 and 1uM, p<0.001), vincristine (p<0.01), and etoposide (p<0.05) were completely reversed. Comparable results were obtained with the HEK-293-B1 cell line in which HG-829 potentiated doxorubicin cytotoxicity 33- and 25-fold at concentrations 0.5uM (p<0.01) and 1uM (p<0.001), respectively. Compared to CsA, HG-829 was 3-fold more potent at equimolar concentrations. Functional studies showed that HG-829 (2.5uM) completely inhibited P-gp mediated rhodamine efflux in K562-R and the HEK transfected cells (p<0.05), but had no effect in parental cells. Pre-incubation followed by inhibitor removal showed that HG-829 inhibited rhodamine export as long as 24h (p<0.05), whereas equivalent concentration of CsA inhibited export for only 30 min. HG-829 showed no consistent effects on P-gp-ATPase activity in membrane preparations, whereas verapamil, a known P-gp substrate, displayed concentration-dependent stimulation. In mice bearing K562-R and parental xenografts, intraperitoneal administration of HG-829 significantly potentiated the antitumor activity of daunomyicin compared to vehicle without a significant increase in toxicity. Tumor volumes in HG-829 treated mice decreased to levels comparable to that of the K562-parental cohort (p<0.01 vs. vehicle). Conclusions: HG-829 is a potent non-substrate inhibitor of P-glycoprotein with a prolonged duration of action. Clinical testing of HG-829 is warranted. Disclosures: No relevant conflicts of interest to declare.

Vitamin D as Radiosensitizer: A Review in Cell Line -

2020 ◽  
Vol 10 (6) ◽  
pp. 315-324
Author(s):  
Fahmi Radityamurti ◽  
Fauzan Herdian ◽  
Tiara Bunga Mayang Permata ◽  
Handoko Handoko ◽  
Henry Kodrat ◽  
...  
Keyword(s):  
Vitamin D ◽  
Cell Differentiation ◽  
Cell Line ◽  
Cell Lines ◽  
Anticancer Agent ◽  
Medical Literature ◽  
In Vitro Studies ◽  
Anti Cancer

Introduction: Vitamin D has been shown to have anti-cancer properties such as antioxidants, anti-proliferative, and cell differentiation. The property of vitamin D as an anticancer agent triggers researchers to find out whether vitamin D is useful as a radiosensitizer. Multiple studies have been carried out on cell lines in various types of cancer, but the benefits of vitamin D as a radiosensitizer still controversial. This paperwork aims to investigate the utilization of Vitamin D3 (Calcitriol) as radiosensitizer in various cell line through literature review.Methods: A systematic search of available medical literature databases was performed on in-vitro studies with Vitamin D as a radiosensitizer in all types of cell lines. A total of 11 in-vitro studies were evaluated.Results: Nine studies in this review showed a significant effect of Vitamin D as a radiosensitizer agent by promoting cytotoxic autophagy, increasing apoptosis, inhibiting of cell survival and proliferation, promoting gene in ReIB inhibition, inducing senescene and necrosis. The two remaining studies showed no significant effect in the radiosensitizing mechanism of Vitamin D due to lack of evidence in-vitro settings.Conclusion: Vitamin D have anticancer property and can be used as a radiosensitizer by imploring various mechanism pathways in various cell lines. Further research especially in-vivo settings need to be evaluated.

scholarly journals Therapeutic evaluation of palbociclib and its compatibility with other chemotherapies for primary and recurrent nasopharyngeal carcinoma

2020 ◽  
Author(s):  
zhichao xue ◽  
Vivian Wai Yan Lui ◽  
Yongshu Li ◽  
Jia Lin ◽  
Chanping You ◽  
...  
Keyword(s):  
Cell Death ◽  
Nasopharyngeal Carcinoma ◽  
Cell Lines ◽  
Chemotherapeutic Drugs ◽  
Induce Cell Cycle Arrest ◽  
Ki 67 ◽  
Concurrent Treatment ◽  
Xenograft Models

Abstract Background: Recent genomic analyses revealed that druggable molecule targets were detectable in approximately 6% of patients with nasopharyngeal carcinoma (NPC). However, a dependency on dysregulated CDK4/6–cyclinD1 pathway signaling is an essential event in the pathogenesis of NPC. In this study, we aimed to evaluate the therapeutic efficacy of a specific CDK4/6 inhibitor, palbociclib, and its compatibility with other chemotherapeutic drugs for the treatment of NPC by using newly established xenograft models and cell lines derived from primary, recurrent, and metastatic NPC. Methods: We evaluated the efficacies of palbociclib monotherapy and concurrent treatment with palbociclib and cisplatin or suberanilohydroxamic acid (SAHA) in NPC cell lines and xenograft models. RNA sequencing was then used to profile the drug response–related pathways. Palbociclib-resistant NPC cell lines were established to determine the potential use of cisplatin as a second-line treatment after the development of palbociclib resistance. We further examined the efficacy of palbociclib treatment against cisplatin-resistant NPC cells. Results: In NPC cells, palbociclib monotherapy was confirmed to induce cell cycle arrest in the G1 phase in vitro . Palbociclib monotherapy also had significant inhibitory effects in all six tested NPC tumor models in vivo , as indicated by substantial reductions in the total tumor volumes and in Ki-67 proliferation marker expression. In NPC cells, concurrent palbociclib treatment mitigated the cytotoxic effect of cisplatin in vitro . Notably, concurrent treatment with palbociclib and SAHA synergistically promoted NPC cell death both in vitro and in vivo . This combination also further inhibited tumor growth by inducing autophagy-associated cell death. NPC cell lines with induced palbociclib or cisplatin resistance remained sensitive to treatment with cisplatin or palbociclib, respectively. Conclusions: Our study findings provide essential support for the use of palbociclib as an alternative therapy for NPC and increase awareness of the effective timing of palbociclib administration with other chemotherapeutic drugs. Our results provide a foundation for the design of first-in-human clinical trials of palbociclib regimens in patients with NPC.

scholarly journals Establishment of a novel human CIC-DUX4 sarcoma cell line, Kitra-SRS, with autocrine IGF-1R activation and metastatic potential to the lungs

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Sho Nakai ◽  
Shutaro Yamada ◽  
Hidetatsu Outani ◽  
Takaaki Nakai ◽  
Naohiro Yasuda ◽  
...  
Keyword(s):  
Cell Line ◽  
Cell Lines ◽  
Fusion Gene ◽  
Primary Tumour ◽  
Chromosomal Rearrangements ◽  
Basic Research ◽  
Metastatic Potential ◽  
Original Tumour

Abstract Approximately 60–70% of EWSR1-negative small blue round cell sarcomas harbour a rearrangement of CIC, most commonly CIC-DUX4. CIC-DUX4 sarcoma (CDS) is an aggressive and often fatal high-grade sarcoma appearing predominantly in children and young adults. Although cell lines and their xenograft models are essential tools for basic research and development of antitumour drugs, few cell lines currently exist for CDS. We successfully established a novel human CDS cell line designated Kitra-SRS and developed orthotopic tumour xenografts in nude mice. The CIC-DUX4 fusion gene in Kitra-SRS cells was generated by t(12;19) complex chromosomal rearrangements with an insertion of a chromosome segment including a DUX4 pseudogene component. Kitra-SRS xenografts were histologically similar to the original tumour and exhibited metastatic potential to the lungs. Kitra-SRS cells displayed autocrine activation of the insulin-like growth factor 1 (IGF-1)/IGF-1 receptor (IGF-1R) pathway. Accordingly, treatment with the IGF-1R inhibitor, linsitinib, attenuated Kitra-SRS cell growth and IGF-1-induced activation of IGF-1R/AKT signalling both in vitro and in vivo. Furthermore, upon screening 1134 FDA-approved drugs, the responses of Kitra-SRS cells to anticancer drugs appeared to reflect those of the primary tumour. Our model will be a useful modality for investigating the molecular pathology and therapy of CDS.

scholarly journals Establishment of B-Cell Lymphoma Cell Lines Persistently Infected with Hepatitis C Virus In Vivo and In Vitro: the Apoptotic Effects of Virus Infection

2003 ◽  
Vol 77 (3) ◽  
pp. 2134-2146 ◽  
Author(s):  
Vicky M.-H. Sung ◽  
Shigetaka Shimodaira ◽  
Alison L. Doughty ◽  
Gaston R. Picchio ◽  
Huong Can ◽  
...  
Keyword(s):  
Hepatitis C ◽  
B Cell ◽  
Cell Line ◽  
Cell Lines ◽  
Culture System ◽  
Cell Lymphoma ◽  
B Cell Lymphoma ◽  
Hcv Rna

ABSTRACT Hepatitis C virus (HCV) is a major cause of chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma. Studies of HCV replication and pathogenesis have so far been hampered by the lack of an efficient tissue culture system for propagating HCV in vitro. Although HCV is primarily a hepatotropic virus, an increasing body of evidence suggests that HCV also replicates in extrahepatic tissues in natural infection. In this study, we established a B-cell line (SB) from an HCV-infected non-Hodgkin's B-cell lymphoma. HCV RNA and proteins were detectable by RNase protection assay and immunoblotting. The cell line continuously produces infectious HCV virions in culture. The virus particles produced from the culture had a buoyant density of 1.13 to 1.15 g/ml in sucrose and could infect primary human hepatocytes, peripheral blood mononuclear cells (PBMCs), and an established B-cell line (Raji cells) in vitro. The virus from SB cells belongs to genotype 2b. Single-stranded conformational polymorphism and sequence analysis of the viral RNA quasispecies indicated that the virus present in SB cells most likely originated from the patient's spleen and had an HCV RNA quasispecies pattern distinct from that in the serum. The virus production from the infected primary hepatocytes showed cyclic variations. In addition, we have succeeded in establishing several Epstein-Barr virus-immortalized B-cell lines from PBMCs of HCV-positive patients. Two of these cell lines are positive for HCV RNA as detected by reverse transcriptase PCR and for the nonstructural protein NS3 by immunofluorescence staining. These observations unequivocally establish that HCV infects B cells in vivo and in vitro. HCV-infected cell lines show significantly enhanced apoptosis. These B-cell lines provide a reproducible cell culture system for studying the complete replication cycle and biology of HCV infections.

scholarly journals Overexpression of cyclin D1 in the Dami megakaryocytic cell line causes growth arrest

Blood ◽  
1995 ◽  
Vol 86 (1) ◽  
pp. 294-304 ◽  
Author(s):  
CC Wilhide ◽  
C Van Dang ◽  
J Dipersio ◽  
AA Kenedy ◽  
PF Bray
Keyword(s):  
Cyclin D1 ◽  
Cell Line ◽  
Cell Lines ◽  
Northern Blotting ◽  
Mrna Levels ◽  
Cyclin Dependent Kinases ◽  
Megakaryocyte Differentiation ◽  
Megakaryocytic Cell

The maturation of megakaryocytes in vivo requires polyploidization or repeated duplication of DNA without cytokinesis. As DNA replication and cytokinesis are tightly regulated in somatic cells by cyclins and cyclin-dependent kinases, we sought to determine the pattern of cyclin gene expression in cells that undergo megakaryocytic differentiation and polyploidization. The Dami megakaryocytic cell line differentiates and increases ploidy in response to phorbol 12-myristate 13-acetate (PMA) stimulation in vitro. We used Northern blotting to analyze mRNA levels of cyclins A, B, C, D1, and E in PMA-induced Dami cells and found that cyclin D1 mRNA levels increased dramatically (18-fold). Similar increases in cyclin D1 mRNA were obtained for other cell lines (HEL and K562) with megakaryocytic properties, but not in HeLa cells. The increase in cyclin D1 was confirmed by Western immunoblotting of PMA-treated Dami cells. This finding suggested that cyclin D1 might participate in megakaryocyte differentiation by promoting endomitosis and/or inhibiting cell division. To address these possibilities, we constructed two stable Zn+2-inducible, cyclin D1-overexpressing Dami cell lines. Cyclin D1 expression alone was not sufficient to induce polyploidy, but in conjunction with PMA-induced differentiation, polyploidization was slightly enhanced. However, unlike other cell systems, cyclin D1 overexpression caused cessation of cell growth. Although the mechanism by which cyclin D1 may affect megakaryocyte differentiation is not clear, these data demonstrate that cyclin D1 is upregulated in differentiating megakaryocytic cells and may contribute to differentiation by arresting cell proliferation.

scholarly journals Comparison of the in vitro and in vivo toxic effects of thymoquinone using oral cancer HSC-3 and HSC-4 cell lines, oral fibroblasts, HACAT cell line, and Zebrafish embryos

2019 ◽  
Vol 16 ◽  
pp. 2108-2114
Author(s):  
Wastuti Hidayati Suriyah ◽  
Abdul Razak Kasmuri ◽  
Fiona How Ni Foong ◽  
Dhona Afriza ◽  
Solachuddin Jauhari Arief Ichwan
Keyword(s):  
Oral Cancer ◽  
Cell Line ◽  
Cell Lines ◽  
Hacat Cell ◽  
Toxic Effects ◽  
Zebrafish Embryos ◽  
Hacat Cell Line

Multi-Targeted Receptor Tyrosine Kinase Inhibitor, ABT-869, Induces Apoptosis and Inhibition of Proliferation of Ba/F3 FLT-3 ITD Mutant Cells.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 1589-1589
Author(s):  
Jenny E. Hernandez ◽  
Junling Li ◽  
Ru-Qi Wei ◽  
Paul Tapang ◽  
Steven K. Davidsen ◽  
...  
Keyword(s):  
Tyrosine Kinase ◽  
Cell Line ◽  
Cell Lines ◽  
Receptor Tyrosine Kinase ◽  
Mutant Cell ◽  
Scid Mice ◽  
Myelogenous Leukemia ◽  
Parp Cleavage ◽  
Mutant Cells

Abstract FLT3 is an receptor tyrosine kinase of the subclass III family that plays a vital role in the regulation of the differentiation, proliferation and survival of normal hematopoietic cells. FLT3 mutations are often found in patients with Acute myelogenous leukemia (AML) and confer poor prognosis. Of these mutations, 15–35% are FLT3 ITD (internal tandem duplication) mutations and 5–7% are point mutations on the FLT3 kinase activation loop (e.g. D835V). Our laboratory is studying the signaling pathways associated with a newly identified multi-targeted tyrosine kinase receptor small molecule inhibitor (RTKI), ABT-869. Recently published work in our laboratory showed that using ABT-869 to treat MV4-11, a human AML FLT-3 ITD mutant cell line, resulted in the inhibition of phosphorylation of FLT-3 with a downstream inhibitory effect on the activation of STAT5, ERK, and Pim-1. Cell viability assays determined that MV-411 cells responded to ABT-869 in a concentration dependent manner (IC50 = 10nM). Apoptosis studies also showed an induction of apoptosis in ABT-869 treated cells. In vivo studies involving xenograft injections of MV-411 cells into SCID mice and subsequent treatment with ABT-869 demonstrated regression of tumor formation. In this study, a Ba/F3 mouse pro-B lymphocytic cell line harboring the FLT-3 ITD or FLT-3 D835V mutation is used as an isolated Flt-3 mutant model system. In vitro, ABT-869 is effective in inhibiting the proliferation of Ba/F3 Flt-3 ITD mutant cells when compared to Ba/F3 Flt-3 D835V mutant and Ba/F3 Flt-3 WT cells. Trypan Blue Exclusion and Alamar Blue assays were used to demonstrate that there is 50% inhibition of growth and proliferation (IC50) of Ba/F3 FLT3 ITD mutant cells at a concentration of 1nM after 48 hours of treatment. Ba/F3 FLT3 D835V mutant cells show an IC50 between 1μM and 10μM after 48 hours of treatment. In contrast, Ba/F3 FLT3 WT cells demonstrate an IC50 of 10μM only after 72 hours of treatment. Annexin V and propidium iodide staining of cells revealed that an increase in apoptosis (41.2%) occurred in Ba/F3 Flt-3 ITD mutant cells treated with 10nM ABT-869 after 24 hours when compared to untreated (6.5%) or vehicle control (6.1%) cells. Staining of Ba/F3 Flt-3 WT treated cell lines revealed no difference in apoptosis when compared to untreated Ba/F3 Flt-3 WT cell only and DMSO controls. PARP cleavage was observed in Ba/F3 FLT-3 ITD mutant cells following treatment with ABT-869 whereas no cleavage was observed with Ba/F3 WT cells treated with ABT-869. In vivo, the activity of ABT-869 treatment of SCID mice injected with Baf3 Flt-3 ITD, Baf3 Flt-3 D835V, or Baf3 Flt-3 WT cells is also being evaluated. Using bioluminescence imaging, it was determined that Ba/F3 FLT-3 ITD mutant and Ba/F3 Flt-3 D835Vmutant cell lines result in metastases and subsequent death in SCID mice after 2 weeks for ITD and 5 weeks for D835V, whereas mice injected with Ba/F3 WT survive longer than 5 weeks. Preliminary data demonstrated that ABT-869 prolonged survival in mice injected with the Ba/F3 FLT3-ITD cells compared to controls. Our preclinical data demonstrate that ABT-869 is effective specifically with FLT-3 ITD mutant cell lines in an isolated system. These studies provide rationale for the treatment of AML patients and the prevention of relapse.

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