Louie Naumovski

Stanford University, Palo Alto, CA, USA

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Publications (16)80.4 Total impact

  • Article: The novel expanded porphyrin, motexafin gadolinium, combined with [90Y]ibritumomab tiuxetan for relapsed/refractory non-Hodgkin's lymphoma: preclinical findings and results of a phase I trial.
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    ABSTRACT: Therapeutic strategies to enhance the efficacy of radioimmunotherapy have not been explored. Motexafin gadolinium is a novel anticancer agent that targets redox-dependent pathways and enhances sensitivity of tumor cells to ionizing radiation. We did preclinical studies examining motexafin gadolinium combined with rituximab and/or radiation in lymphoma cells. We subsequently completed a phase I clinical trial combining escalating doses of motexafin gadolinium concurrently with standard [(90)Y]ibritumomab tiuxetan for patients with relapsed/refractory non-Hodgkin's lymphoma. In HF1 lymphoma cells, motexafin gadolinium and rituximab resulted in synergistic cytotoxicity (combination index, 0.757) through a mitochondrial-mediated caspase-dependent pathway, whereas cell death in Ramos and SUDHL4 cells was additive. Motexafin gadolinium/rituximab combined with radiation (1-3 Gy) resulted in additive apoptosis. Twenty-eight of 30 patients were evaluable on the phase I clinical trial. Median age was 65 years (47-87 years), and histologies were marginal-zone (n = 1), mantle-cell (n = 3), diffuse large cell (n = 6), and follicular lymphoma (n = 18). Of all patients, 86% were rituximab refractory. Therapy was well tolerated, and no dose-limiting toxicity was seen. Overall response rate was 57% [complete remission (CR), 43%], with median time-to-treatment failure of 10 months (1-48+ months) and median duration-of-response of 17 months. Of note, all responses were documented at 4 weeks. Furthermore, in rituximab-refractory follicular lymphoma (n = 14), overall response rate was 86% (CR, 64%), with a median time-to-treatment failure of 14 months (2-48+ months). This represents the first report of a novel agent to be combined safely concurrently with radioimmunotherapy. Furthermore, tumor responses with [(90)Y]ibritumomab tiuxetan/motexafin gadolinium were prompt with a high rate of CRs, especially in rituximab-refractory follicular lymphoma.
    Clinical Cancer Research 10/2009; 15(20):6462-71. · 7.74 Impact Factor
  • Article: Effects of motexafin gadolinium in a phase II trial in refractory chronic lymphocytic leukemia.
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    ABSTRACT: Chronic lymphocytic leukemia (CLL) cells are susceptible to oxidative stress. The expanded porphyrin, motexafin gadolinium (MGd), reacts with intracellular reducing metabolites and protein thiols to generate reactive oxygen species (ROS). A phase II trial administered MGd 5 mg/kg/day IV for 5 days every 3 weeks until disease progression to patients with previously treated CLL and small lymphocytic lymphoma. Thirteen patients (median age 66 years) with a median of four prior therapies (range 2-9) were enrolled. Modest anti-tumor activity was seen in three patients, with improvement in lymphocytosis, lymphadenopathy and/or splenomegaly, but no patient achieved a partial or complete response by NCI 96 criteria. Flow cytometry confirmed tumor uptake of MGd. Serial increase in AKT phosphorylation in patient samples following MGd treatment was not observed, suggesting intracellular generation of ROS was not optimal. Therefore, this schedule of administration achieved MGd uptake into primary tumor cells in vivo, but clinical activity was modest.
    Leukemia & lymphoma 10/2009; 50(12):1977-82. · 2.40 Impact Factor
  • Article: Apoptosis-stimulating protein of p53 (ASPP2) heterozygous mice are tumor-prone and have attenuated cellular damage-response thresholds.
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    ABSTRACT: The expression of ASPP2 (53BP2L), a proapoptotic member of a family of p53-binding proteins, is frequently suppressed in many human cancers. Accumulating evidence suggests that ASPP2 inhibits tumor growth; however, the mechanisms by which ASPP2 suppresses tumor formation remain to be clarified. To study this, we targeted the ASPP2 allele in a mouse by replacing exons 10-17 with a neoR gene. ASPP2(-/-) mice were not viable because of an early embryonic lethal event. Although ASPP2(+/-) mice appeared developmentally normal, they displayed an increased incidence of a variety of spontaneous tumors as they aged. Moreover, gamma-irradiated 6-week-old ASPP2(+/-) mice developed an increased incidence of high-grade T cell lymphomas of thymic origin compared with ASPP2(+/+) mice. Primary thymocytes derived from ASPP2(+/-) mice exhibited an attenuated apoptotic response to gamma-irradiation compared with ASPP2(+/+) thymocytes. Additionally, ASPP2(+/-) primary mouse embryonic fibroblasts demonstrated a defective G(0)/G(1) cell cycle checkpoint after gamma-irradiation. Our results demonstrate that ASPP2 is a haploinsufficient tumor suppressor and, importantly, open new avenues for investigation into the mechanisms by which disruption of ASPP2 pathways could play a role in tumorigenesis and response to therapy.
    Proceedings of the National Academy of Sciences 03/2009; 106(11):4390-5. · 9.68 Impact Factor
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    Article: Motexafin gadolinium-induced cell death correlates with heme oxygenase-1 expression and inhibition of P450 reductase-dependent activities.
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    ABSTRACT: Heme oxygenase-1 (HO1), which oxidizes heme to biliverdin, CO, and free iron, conveys protection against oxidative stress and is antiapoptotic. Under stress conditions, some porphyrin derivatives can inhibit HO1 and trigger cell death. Motexafin gadolinium (MGd) is an expanded porphyrin that selectively targets cancer cells through a process of futile redox cycling that decreases intracellular reducing metabolites and protein thiols. Here, we report that hematopoietic-derived cell lines that constitutively express HO1 are more susceptible to MGd-induced apoptosis than those that do not. MGd used in combination with tin protoporphyrin IX, an inhibitor of HO1, resulted in synergistic cell killing. Consistent with these cell culture observations, we found that MGd is an inhibitor of heme oxygenase-1 activity in vitro. We demonstrate that inhibition of HO1 reflects an interaction of MGd with NADPH-cytochrome P450 reductase, the electron donor for HO1, that results in diversion of reducing equivalents from heme oxidation to oxygen reduction. In accord with this mechanism, MGd is also an in vitro inhibitor of CYP2C9, CYP3A4, and CYP4A1. Inhibition of HO1 by MGd may contribute to its anticancer activity, whereas its in vitro inhibition of a broad spectrum of P450 enzymes indicates that a potential exists for drug-drug interactions.
    Molecular Pharmacology 02/2007; 71(1):193-200. · 4.88 Impact Factor
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    Article: Synthesis and biologic properties of hydrophilic sapphyrins, a new class of tumor-selective inhibitors of gene expression.
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    ABSTRACT: Sapphyrin analogues and related porphyrin-like species have attracted attention as anticancer agents due to their selective localization in various cancers, including hematologic malignancies, relative to surrounding tissues. Sapphyrins are electron affinic compounds that generate high yields of singlet oxygen formation. Although initially explored in the context of photodynamic therapy, sapphyrins have intrinsic anticancer activity that is independent of their photosensitizing properties. However, the mechanisms for their anticancer activity have not been fully elucidated. We have prepared a series of hydrophilic sapphyrins and evaluated their effect on proliferation, uptake, and cell death in adherent human lung (A549) and prostate (PC3) cancer cell lines and in an A549 xenograft tumor model. PCI-2050, the sapphyrin derivative with the highest in vitro growth inhibitory activity, significantly lowered 5-bromo-2'-deoxyuridine incorporation in S-phase A549 cells by 60% within eight hours and increased levels of reactive oxygen species within four hours. The growth inhibition pattern of PCI-2050 in the National Cancer Institute 60 cell line screen correlated most closely using the COMPARE algorithm with known transcriptional or translational inhibitors. Gene expression analyses conducted on A549 plateau phase cultures treated with PCI-2050 uncovered wide-spread decreases in mRNA levels, which especially affected short-lived transcripts. Intriguingly, PCI-2050 increased the levels of transcripts involved in RNA processing and trafficking, transcriptional regulation, and chromatin remodeling. We propose that these changes reflect the activation of cellular processes aimed at countering the observed wide-spread reductions in transcript levels. In our A549 xenograft model, the two lead compounds, PCI-2050 and PCI-2022, showed similar tumor distributions despite differences in plasma and kidney level profiles. This provides a possible explanation for the better tolerance of PCI-2022 relative to PCI-2050. Hydrophilic sapphyrins were found to display promise as novel agents that localize to tumors, generate oxidative stress, and inhibit gene expression.
    Molecular Cancer 02/2007; 6:9. · 3.99 Impact Factor
  • Article: Tumor localization and antitumor efficacy of novel sapphyrin compounds.
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    ABSTRACT: Sapphyrins are pentapyrrolic metal-free expanded porphyrins with potential medical use as anticancer agents. The novel sapphyrin derivative, PCI-2050, functionalized with 2-[2-(2-methoxyethoxy)ethoxy]ethoxy groups to enhance solubility and a modified bipyrrole moiety was found to be more potent in inducing apoptosis than the previously described sapphyrin PCI-2000. Because some sapphyrins may localize to tumors, we took advantage of the intrinsic fluorescence of these compounds to develop a flow cytometry-based assay to track sapphyrin biodistribution in tumor-bearing mice. Ex vivo analysis of sapphyrin-injected animals revealed that PCI-2050 preferentially localized to tumor, whereas PCI-2000 distributed into normal tissues rather than tumor. PCI-2050 uptake in xenograft tumor cells and resultant tumor cell cytotoxicity was dose dependent. To investigate structure-activity relationships, we focused on PCI-2050 and three derivatives that differ by their alkyl substituents on the bipyrrole moiety: PCI-2051, PCI-2052, and PCI-2053. Treatment of Ramos cells in culture or treatment of Ramos xenograft-bearing animals with each of the sapphyrins followed by ex vivo growth of tumor cells revealed the same pattern of cytotoxicity: PCI-2050 > PCI-2052 > PCI-2051 > PCI-2053. Thus, subtle changes in the alkyl substituents on the bipyrrole moiety result in significant changes in antitumor activity. PCI-2050 displayed significant antitumor efficacy in both Ramos and RKO xenograft models without hematologic, hepatic, or renal abnormalities as assessed by complete blood counts and serum chemistries. On the basis of these findings, it is concluded that the sapphyrin PCI-2050 warrants further evaluation as a potential anticancer agent due to its intrinsic proapoptotic activity and tumor localization ability.
    Molecular Cancer Therapeutics 11/2006; 5(11):2798-805. · 5.23 Impact Factor
  • Article: Motexafin gadolinium modulates levels of phosphorylated Akt and synergizes with inhibitors of Akt phosphorylation.
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    ABSTRACT: Motexafin gadolinium (MGd, Xcytrin) is a tumor-selective expanded porphyrin that targets oxidative stress-related proteins. MGd treatment of the follicular lymphoma-derived cell line HF-1 resulted in growth suppression and apoptosis whereas MGd treatment of the Burkitt's lymphoma-derived cell line Ramos resulted in growth suppression but not apoptosis. Because phosphorylation status of Akt/protein kinase B is regulated by oxidative stress, we monitored total and phosphorylated Akt (pAkt) in MGd-treated HF-1 and Ramos cells. Levels of pAkt increased within 30 minutes after MGd treatment of HF-1 but after 4 hours began to show a progressive decline to below baseline levels before cells underwent apoptosis. In MGd-treated Ramos cells, pAkt increased approximately 2-fold within 4 hours and remained persistently elevated. Because pAkt activates survival pathways, we determined if MGd-induced cell death could be enhanced by inhibiting phosphorylation of Akt. The addition of specific inhibitors of Akt phosphorylation (Akt inhibitor 1 or SH-5) reduced pAkt levels in MGd-treated HF-1 and Ramos cells and synergistically enhanced MGd-induced cell death. MGd was also evaluated in combination with celecoxib, an inhibitor of Akt phosphorylation, or docetaxel, a microtubule inhibitor that can decrease Akt phosphorylation. The combination of MGd/celecoxib or MGd/docetaxel resulted in decreased Akt phosphorylation and in synergistic cytotoxicity compared with either agent alone. These data point to a potential protective role for pAkt in MGd-induced apoptosis and suggest that MGd activity may be enhanced by combining it with agents that inhibit Akt phosphorylation.
    Molecular Cancer Therapeutics 06/2006; 5(5):1176-82. · 5.23 Impact Factor
  • Article: New polyethyleneglycol-functionalized texaphyrins: synthesis and in vitro biological studies.
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    ABSTRACT: The synthesis of four new analogues of motexafin gadolinium (MGd), a gadolinium(III) texaphyrin complex in clinical trials for its anticancer properties, is described. These new derivatives contain either 1,2-diaminobenzene or 2,3-diaminonaphthalene subunits as the source of the imine nitrogens and bear multiple 2-[2-(2-methoxyethoxy)ethoxy]ethoxy (PEG) groups, on either meso aryl or beta-pyrrolic substituents, to increase their water solubility. All four analogues were found to be more active in vitro than the parent system MGd as judged from cell proliferation assays using the PC3 and A549 cell lines.
    Dalton Transactions 05/2006; · 3.84 Impact Factor
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    Article: Motexafin gadolinium and zinc induce oxidative stress responses and apoptosis in B-cell lymphoma lines.
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    ABSTRACT: There is an emerging appreciation of the importance of zinc in regulating cancer cell growth and proliferation. Recently, we showed that the anticancer agent motexafin gadolinium (MGd) disrupted zinc metabolism in A549 lung cancer cells, leading, in the presence of exogenous zinc, to cell death. Here, we report the effect of MGd and exogenous zinc on intracellular levels of free zinc, oxidative stress, proliferation, and cell death in exponential phase human B-cell lymphoma and other hematologic cell lines. We find that increased levels of oxidative stress and intracellular free zinc precede and correlate with cell cycle arrest and apoptosis. To better understand the molecular basis of these cellular responses, gene expression profiling analyses were conducted on Ramos cell cultures treated with MGd and/or zinc acetate. Cultures treated with MGd or zinc acetate alone elicited transcriptional responses characterized by induction of metal response element-binding transcription factor-1 (MTF-1)-regulated and hypoxia-inducible transcription factor-1 (HIF-1)-regulated genes. Cultures cotreated with MGd and zinc acetate displayed further increases in the levels of MTF-1- and HIF-1-regulated transcripts as well as additional transcripts regulated by NF-E2-related transcription factor 2. These data provide insights into the molecular changes that accompany the disruption of intracellular zinc homeostasis and support a role for MGd in treatment of B-cell hematologic malignancies.
    Cancer Research 01/2006; 65(24):11676-88. · 7.86 Impact Factor
  • Article: Control of ASPP2/(53BP2L) protein levels by proteasomal degradation modulates p53 apoptotic function.
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    ABSTRACT: The p53 pathway is a central mediator of the apoptotic response. ASPP2/(53BP2L) (apoptosis-stimulating protein of p53 2, also known as 53BP2L) enhances apoptosis through selective stimulation of p53 transactivation of proapoptotic target genes. Although the Rb/E2F pathway regulates ASPP2/(53BP2L) transcription, the complex mechanisms controlling ASPP2/(53BP2L) levels and function remain unknown. We now report that proteasomal degradation modulates ASPP2/(53BP2L) protein levels and apoptotic function. Treatment of cells with proteasomal inhibitors, including the clinically utilized proteasomal inhibitor bortezomib, increases ASPP2/(53BP2L) protein but not RNA levels. Likewise, anthracycline-based chemotherapy, which has multiple mechanisms of action, including proteasomal inhibition, increases ASPP2/(53BP2L) protein but not RNA levels. Proteasomal inhibition or anthracycline treatment increases ASPP2/(53BP2L) protein stability and half-life. Furthermore, the central region of the ASPP2/(53BP2L) protein is ubiquitinated as would be expected for a proteasomal substrate. More importantly, small interfering RNA knockdown of ASPP2/(53BP2L) levels attenuated bortezomib-induced apoptosis, and this effect was greater in wild-type p53 cells. Because elevated levels of ASPP2/(53BP2L) are proapoptotic, these results described an important new molecular mechanism that modulates the p53-ASPP2/(53BP2L) apoptotic pathway.
    Journal of Biological Chemistry 11/2005; 280(41):34473-80. · 4.77 Impact Factor
  • Article: Sapphyrins induce apoptosis in hematopoietic tumor-derived cell lines and show in vivo antitumor activity.
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    ABSTRACT: Sapphyrins are pentapyrrolic, metal-free, expanded porphyrins. In the present study, the activity of sapphyrins as anticancer agents in hematopoietic-derived tumor cells was explored. It was found that a dihydroxylated water-soluble sapphyrin derivative (PCI-2000) is a potent inducer of apoptosis in a wide variety of tumor cell lines including lymphoma (Ramos, DHL-4, and HF-1), leukemia (Jurkat and HL-60), and myeloma (8226/S, 1-310, C2E3, and 1-414). PCI-2000 triggers an apoptotic pathway in these tumor cells as shown by release of cytochrome c from mitochondria; activation of caspases 9, 8, and 3; cleavage of the caspase substrate poly(ADP-ribose) polymerase; and Annexin V binding. Apoptosis can be partially inhibited by overexpression of the antiapoptotic protein Bcl-2 or treatment with benzyloxycarbonyl-valine-alanine-aspartic acid-fluoromethylketone, a cell-permeable caspase inhibitor. Both PCI-2000 and PCI-2010, a tetrahydroxy bis-carbamate derivative of PCI-2000, result in increased levels of phosphorylated p38 mitogen-activated protein kinase. Inhibition of p38 mitogen-activated protein kinase phosphorylation resulted in a synergistic increase of PCI-2000 cytotoxicity. PCI-2010 showed less toxicity in mice than PCI-2000 and was active in slowing the growth of Ramos and HL-60 tumor xenografts in nude mice. These results provide preclinical rationale for the further study of sapphyrins for potential use in the treatment of hematopoietic-derived tumors.
    Molecular Cancer Therapeutics 07/2005; 4(6):968-76. · 5.23 Impact Factor
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    Article: A practical guideline for calculating parenteral nutrition cycles.
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    ABSTRACT: Both physiologic and psychological reasons for cycling total parenteral nutrition (TPN) have been well established. Despite widespread acceptance of this practice, the only previously published method for calculating TPN cycle rates is inherently flawed. A mathematical formula was derived to facilitate reliable calculation of cyclic TPN flow rates as a function of total volume and cycle time. A publicly accessible website was subsequently developed to expedite rapid determination of TPN cycles. A fail-safe method of calculating TPN cycle flow rates can be expressed as F = V/(4T-10), where F is equal to the basal flow rate (mL/h), T is equal to the desired cycle time (hours), and V is equal to the total volume of TPN (mL) to be delivered in 24 hours. The basal flow rate and twice the basal flow rate are used for the first and last 2 hours of the TPN cycle, and the remainder of the cycle runs at 4 times the basal flow rate. TPN cycles may be easily calculated online using this formula at http://peds.stanford.edu/tpn.html. We have developed a fail-safe method of calculating TPN cycle flow rates that will consistently deliver the desired volume and have made an online implementation of this formula publicly available.
    Nutrition in Clinical Practice 01/2004; 18(6):517-20. · 1.59 Impact Factor
  • Article: ARMER, apoptotic regulator in the membrane of the endoplasmic reticulum, a novel inhibitor of apoptosis.
    Hannah M Lui, Jun Chen, Lingli Wang, Louie Naumovski
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    ABSTRACT: We have identified a novel protein, apoptotic regulator in the membrane of the endoplasmic reticulum (ARMER), which protects HT1080 fibrosarcoma cells from apoptosis induced by various stimuli. We demonstrate that ARMER is an endoplasmic reticulum (ER) integral membrane protein with four predicted transmembrane domains and a COOH-terminal KKXX ER retrieval motif. We used an inducible expression system (pIND) to study the effects of regulated ARMER overexpression. Cells in which ARMER was overexpressed exhibited protection from multiple apoptotic inducers including serum starvation, doxorubicin, UV irradiation, tumor necrosis factor alpha, and the ER stressors brefeldin A, tunicamycin, and thapsigargin. Analysis of the caspase proteolytic cascade reveals that ARMER inhibits proteolysis of the caspase-9-specific fluorogenic substrate LEHD-AFC as well as endogenous substrates downstream of caspase-9; however, it does not inhibit cytochrome c release or cleavage of caspase-9 itself. Apoptotic stimuli cause endogenous levels of ARMER protein and RNA to decrease, leading to cell death; however, sustaining ARMER protein levels through exogenous expression inhibits apoptosis. These data suggest that ARMER is a novel ER integral membrane protein which protects cells by inhibiting caspase-9 activity and reveal a possible role for ARMER in cell survival.
    Molecular Cancer Research 06/2003; 1(7):508-18. · 4.29 Impact Factor
  • Article: Groups of p53 target genes involved in specific p53 downstream effects cluster into different classes of DNA binding sites.
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    ABSTRACT: The tumor suppressor protein p53, once activated, can cause either cell cycle arrest or apoptosis through transactivation of target genes with p53 DNA binding sites (DBS). To investigate the role of p53 DBS in the regulation of this profound, yet poorly understood decision of life versus death, we systematically studied all known and potential p53 DBS. We analysed the DBS separated from surrounding promoter regions in yeast and mammalian assays with and without DNA damage. p53 efficiently utilized the DBS of MDM2 and of genes connected to cell cycle arrest, DNA repair and the death receptor pathway of apoptosis. However, p53 was unable to utilize two-thirds of the isolated DBS, a subset that included almost all DBS of apoptosis-related genes. Neither ASPP2, a p53-interacting protein reported to specifically stimulate p53 transcriptional activity on apoptosis-related promoters, nor DNA damage resulted in p53 utilization of isolated DBS of apoptosis-related genes. Thus, a major regulation of p53 activity occurs at the level of p53 DBS themselves by posing additional requirements for the successful utilization of apoptosis-related DBS.
    Oncogene 12/2002; 21(51):7901-11. · 6.37 Impact Factor
  • Article: Inhibition of cell death by ribosomal protein L35a.
    Charles D Lopez, Gary Martinovsky, Louie Naumovski
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    ABSTRACT: In order to better understand how tumor cells develop resistance to chemotherapy drugs, we screened a human cDNA expression library in Jurkat cells for cDNA's that conferred resistance to doxorubicin-induced cell death. One of the cDNA's isolated in the screen codes for ribosomal protein L35a, a component of the large subunit of the ribosome. Jurkat cells engineered to overexpress L35a protein were more resistant not only to doxorubicin but also to UV-irradiation, anti-Fas antibody, and serum starvation compared to Jurkat cells expressing endogenous levels of L35a. Jurkat cells overexpressing L35a did not have increased levels of the anti-apoptotic proteins Bcl-2 or Bcl-xL, the drug efflux pump P-glycoprotein, nor altered cellular growth kinetics or total protein synthesis. Our results provide new insight into L35a function and suggest that it may have a role in the cellular response to cytotoxic damage. Since L35a RNA is overexpressed in a significant number of glioblastoma multiforme (GBM) brain tumors, our results may stimulate further investigation into the possible role of L35a in the resistance of GBM to cytotoxic therapy.
    Cancer Letters 07/2002; 180(2):195-202. · 4.24 Impact Factor
  • Article: Intracellular redistribution of interferon-inducible proteins Nmi and IFP 35 in apoptotic cells.
    Jun Chen, Louie Naumovski
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    ABSTRACT: As a consequence of the activation of the apoptotic pathway, the subcellular localization of many proteins that modulate cell death is altered. Nmi and IFP 35 are homologous interferon (IFN)-inducible proteins that associate into a 300-400-kDa complex in the cytoplasm. Prior to treatment with IFN, subcellular fractionation reveals that the proteins are found primarily in a soluble cytoplasmic fraction, and immunofluorescence shows a diffuse cytoplasmic distribution. Treatment with IFN results in some Nmi and IFP 35 fractionating with membranes and colocalizing into speckles as detected by immunofluorescence. In IFN-treated apoptotic cells, the speckles dissociate and are replaced by a diffuse cytoplasmic distribution of Nmi and IFP 35. In Jurkat cells, dissociation of speckles could not be separated from other markers of apoptosis, including exposure of phosphatidylserine on the cell surface, caspase cleavage of D4-GDI, and nuclear condensation and fragmentation. The caspase inhibitor, zVAD-fmk, was not able to inhibit the dissociation of speckles in vivo or in a permeabilized cell assay in vitro, suggesting that dissociation of speckles is a caspase-independent process. Nmi and IFP 35 proteins are not caspase substrates, as total levels of Nmi and IFP 35 and their association into a cytoplasmic complex do not change in apoptotic cells. Consistent with dissociation of speckles, subcellular fractionation studies show redistribution of Nmi and IFP 35 from the membrane fraction into the S100 fraction of apoptotic cells. Our studies have revealed dissociation of the IFN-induced Nmi/IFP 35 speckles as a newly defined specific event occurring during apoptosis.
    Journal of Interferon & Cytokine Research 03/2002; 22(2):237-43. · 3.06 Impact Factor