scholarly journals Induction of Apoptosis, Autophagy and Ferroptosis by Thymus vulgaris and Arctium lappa Extract in Leukemia and Multiple Myeloma Cell Lines

Molecules ◽  
2020 ◽  
Vol 25 (21) ◽  
pp. 5016
Author(s):  
Aveen N. Adham ◽  
Mohamed Elamir F. Hegazy ◽  
Alaadin M. Naqishbandi ◽  
Thomas Efferth

Thymus vulgaris and Arctium lappa have been used as a folk remedy in the Iraqi Kurdistan region to deal with different health problems. The aim of the current study is to investigate the cytotoxicity of T. vulgaris and A. lappa in leukemia and multiple myeloma (MM) cell lines and determine the mode of cell death triggered by the most potent cytotoxic fractions of both plants in MM. Resazurin assay was used to evaluate cytotoxic and ferroptosis activity, apoptosis, and modulation in the cell cycle phase were investigated via Annexin V-FITC/PI dual stain and cell-cycle arrest assays. Furthermore, we used western blotting assay for the determination of autophagy cell death. n-Hexane, chloroform, ethyl acetate, and butanol fractions of T. vulgaris and A. lappa exhibited cytotoxicity in CCRF-CEM and CEM/ADR 5000 cell lines at concentration range 0.001–100 μg/mL with potential activity revealed by chloroform and ethyl acetate fractions. NCI-H929 displayed pronounced sensitivity towards T. vulgaris (TCF) and A. lappa (ACF) chloroform fractions with IC50 values of 6.49 ± 1.48 and 21.9 ± 0.69 μg/mL, respectively. TCF induced apoptosis in NCI-H929 cells with a higher ratio (71%), compared to ACF (50%) at 4 × IC50. ACF demonstrated more potent autophagy activity than TCF. TCF and ACF induced cell cycle arrest and ferroptosis. Apigenin and nobiletin were identified in TCF, while nobiletin, ursolic acid, and lupeol were the main compounds identified in ACF. T. vulgaris and A. lappa could be considered as potential herbal drug candidates, which arrest cancer cell proliferation by induction of apoptosis, autophagic, and ferroptosis.

2004 ◽  
Vol 52 (5) ◽  
pp. 335-344 ◽  
Author(s):  
Naomi Gronich ◽  
Liat Drucker ◽  
Hava Shapiro ◽  
Judith Radnay ◽  
Shai Yarkoni ◽  
...  

BackgroundAccumulating reports indicate that statins widely prescribed for hypercholesteromia have antineoplastic activity. We hypothesized that because statins inhibit farnesylation of Ras that is often mutated in multiple myeloma (MM), as well as the production of interleukin (IL)-6, a key cytokine in MM, they may have antiproliferative and/or proapoptotic effects in this malignancy.MethodsU266, RPMI 8226, and ARH77 were treated with simvastatin (0-30 μM) for 5 days. The following aspects were evaluated: viability (IC50), cell cycle, cell death, cytoplasmic calcium ion levels, supernatant IL-6 levels, and tyrosine kinase activity.ResultsExposure of all cell lines to simvastatin resulted in reduced viability with IC50s of 4.5 μM for ARH77, 8 μM for RPMI 8226, and 13 μM for U266. The decreased viability is attributed to cell-cycle arrest (U266, G1; RPMI 8226, G2M) and cell death. ARH77 underwent apoptosis, whereas U266 and RPMI 8226 displayed a more necrotic form of death. Cytoplasmic calcium levels decreased significantly in all treated cell lines. IL-6 secretion from U266 cells was abrogated on treatment with simvastatin, whereas total tyrosine phosphorylation was unaffected.ConclusionsSimvastatin displays significant antimyeloma activity in vitro. Further research is warranted for elucidation of the modulated molecular pathways and clinical relevance.


Molecules ◽  
2020 ◽  
Vol 25 (11) ◽  
pp. 2687
Author(s):  
Mateus L. Nogueira ◽  
Emilly J. S. P. de Lima ◽  
Asenate A. X. Adrião ◽  
Sheila S. Fontes ◽  
Valdenizia R. Silva ◽  
...  

Cyperus articulatus L. (Cyperaceae), popularly known in Brazil as “priprioca” or “piriprioca”, is a tropical and subtropical plant used in popular medical practices to treat many diseases, including cancer. In this study, C. articulatus rhizome essential oil (EO), collected from the Brazilian Amazon rainforest, was addressed in relation to its chemical composition, induction of cell death in vitro and inhibition of tumor development in vivo, using human hepatocellular carcinoma HepG2 cells as a cell model. EO was obtained by hydrodistillation using a Clevenger-type apparatus and characterized qualitatively and quantitatively by gas chromatography coupled to mass spectrometry (GC-MS) and gas chromatography with flame ionization detection (GC-FID), respectively. The cytotoxic activity of EO was examined against five cancer cell lines (HepG2, HCT116, MCF-7, HL-60 and B16-F10) and one non-cancerous one (MRC-5) using the Alamar blue assay. Cell cycle distribution and cell death were investigated using flow cytometry in HepG2 cells treated with EO after 24, 48 and 72 h of incubation. The cells were also stained with May–Grunwald–Giemsa to analyze the morphological changes. The anti-liver-cancer activity of EO in vivo was evaluated in C.B-17 severe combined immunodeficient (SCID) mice with HepG2 cell xenografts. The main representative substances of this EO sample were muskatone (11.6%), cyclocolorenone (10.3%), α-pinene (8.26%), pogostol (6.36%), α-copaene (4.83%) and caryophyllene oxide (4.82%). EO showed IC50 values for cancer cell lines ranging from 28.5 µg/mL for HepG2 to >50 µg/mL for HCT116, and an IC50 value for non-cancerous of 46.0 µg/mL (MRC-5), showing selectivity indices below 2-fold for all cancer cells tested. HepG2 cells treated with EO showed cell cycle arrest at G2/M along with internucleosomal DNA fragmentation. The morphological alterations included cell shrinkage and chromatin condensation. Treatment with EO also increased the percentage of apoptotic-like cells. The in vivo tumor mass inhibition rates of EO were 46.5–50.0%. The results obtained indicate the anti-liver-cancer potential of C. articulatus rhizome EO.


Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 3066-3066 ◽  
Author(s):  
Luigi Scotto ◽  
Kelly Zullo ◽  
Xavier Jirau Serrano ◽  
Laura K Fogli ◽  
Owen A. O'Connor

Abstract Mantle cell lymphoma (MCL) is a disease characterized by gross cell cycle dysregulation driven by the constitutive overexpression of cyclin D1. The identification of a “proliferation signature” in MCL, underscores the necessity of new therapeutic approaches aimed at lowering the proliferative signature of the disease, theoretically shifting the prognostic features of the disease. Romidepsin, an HDAC inhibitor (HDACi) approved for the treatment of relapsed T-cell lymphoma, is thought to induce cell cycle arrest and apoptosis. Central to the block of cell proliferation is the up-regulation of the cdk inhibitor p21Cip1/Waf1. However up-regulation of p21Cip1/Waf1 has also been shown to reduce sensitivity to romidepsin. HDACi activates p21Cip1/Waf1 expression via ATM and KU60019, a specific ATM inhibitor, has been shown to decrease the p21Cip1/Waf1 protein levels in a concentration dependent manner. We sought to explore the effect of the combination of romidepsin and KU60019 in inducing cell death in MCL. Analysis of romidepsin treated Jeko-1 cell extracts showed a marked effect on the expression of proteins involved in cell cycle regulation. Decrease expression of Emi1, a mitotic regulator required for the accumulation of the APC/C substrates was observed. Emi1 is also responsible for the stability of the E3 ubiquitin ligase Skp2 that specifically recognizes and promotes the degradation of phosphorylated cdk inhibitor p27. However, decrease in Emi1 protein levels, upon addition of romidepsin, was not followed by an increased expression of the cdk inhibitor p27. On the other end, increased expression of the cdk inhibitor p21Cip1/Waf1, was a common feature of all romidepsin treated MCL lines analyzed. Cell cycle analysis via Fluorescent Activated Cell Sorting (FACS) of romidepsin treated Jeko-1 cells showed an accumulation of romidepsin treated cells in the G2/M phase when compared to the control suggesting a p21Cip1/Waf1 induced cell cycle arrest. For all cytotoxicity assays, luminescent cell viability was performed using CellTiter-GloTM followed by acquisition on a Biotek Synergy HT and IC50s calculated using the Calcusyn software. Drug: drug interactions were analyzed using the calculation of the relative risk ratios (RRR). Synergy analyses were performed using Jeko-1, Maver-1 and Z-138 cells treated with different concentrations of romidepsin corresponding to IC10-20 in combination with KU60019 at a concentration of 2.5, 5.0, 7.5 and 15 umol/L for 24, 48 and 72 hours. A synergistic cytotoxic effect was observed in all MCL cell lines when the HDACi was combined with KU60019 throughout the range of all concentrations. The RRR analysis showed a strong synergism at 48 and 72 hours in virtually all combinations of HDACi and KU60019 in all three cell lines. The results of drug:drug combination in two of the three cell lines are shown below. Protein expression analysis of Jeko-1 and Maver-1cells treated with single agents or combinations for 48 hours revealed changes in a host of proteins known to be involved in cell cycle control and apoptosis. The increased p21 protein expression upon addition of romidepsin, was not observed when the romidepsin treatment was combined with the KU60019. Increased activation of the programmed cell death proteins Caspase 8, induced by Fas, and Caspase 3 was observed upon combinations of the single agents in all three cell lines, resulting in an increased cleavage of Poly (ADP-ribose) polymerase (PARP-1). Finally, the abundance of the anti-apoptotic proteins Bcl-XL and BCL-2 showed a significant decrease after treatment with romidepsin plus increase concentrations of KU60019 when compared with their abundance in the presence of the single agents. Cell cycle analysis of Jeko-1 cells treated for 24 hours with single agents and combination suggests that the increased apoptosis is the result of inhibition of the p21Cip1/Waf1 induced G2/M cell cycle arrest by KU60019. Overall, these data demonstrated that the combination of romidepsin and KU60019 was synergistically effective in inhibiting the in vitro growth of the mantle cell lymphoma lines. Jeko-1 Maver-1 Disclosures: O'Connor: Celgene: Consultancy, Research Funding.


Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 1706-1706
Author(s):  
Kenneth H Shain ◽  
Danielle Yarde ◽  
Mark Mead ◽  
Lori Hazlehurst ◽  
William S Dalton

Abstract Multiple Myeloma (MM) is a B cell malignancy characterized by the monoclonal expansion of plasma cells. Although numerous genetic alterations have been implicated in MM pathogenesis, it is widely hypothesized that the bone marrow (BM) microenvironment contributes to MM cell pathogenesis. The BM microenvironmental components, interleukin (IL)-6 and fibronectin (FN), have individually been shown to influence the proliferation and survival of MM cells; however, in vivo these effectors most likely work together. We examined signaling events, cell cycle progression, and levels of drug response in MM cells either adhered to FN via β1 integrins, stimulated with IL-6, or with the two combined. IL-6 and FN adhesion have been demonstrated to protect cells from a host of cytotoxic stimuli suggesting co-stimulation of MM cell lines with IL-6 and FN-adhesion may confer a greater protection against chemotherapeutics than either effector alone. However, MTT cytotoxicity assays demonstrate that although adhesion to FN provides significant protection against treatment with mitoxantrone or doxorubicin (p=0.0002 and p=<0.0001 respectively), the addition of IL-6 provides no further protection. These findings were corroborated by analysis of drug-mediated apoptosis using FCM by Annexin-V/7-AAD. In regards to cell cycle kinetics, our laboratory has previously demonstrated that adhesion of the 8226 MM cell line to FN mediated a p27Kip1 dependent G0/G1 cell cycle arrest. As predicted, BrdU/PI analysis of 8226 cells adhered to FN for 24 hours results in an increased number of cells in G0/G1 relative to cells maintained in suspension (p=0.0028). In contrast, when cells were adhered to FN in the presence of IL-6 no accumulation of cells in G0/G1 was observed, with levels similar to that observed in cells maintained in suspension with or without stimulation by IL-6. Our studies demonstrated that the G1/S cell cycle arrest associated with FN adhesion of MM cell lines was overcome when IL-6 was added; however, the cell adhesion mediated drug resistance (CAM-DR) was maintained in the presence of IL-6. Investigation of the biochemical signaling following concomitant exposure of MM cells to IL-6 and FN adhesion revealed a synergistic increase in STAT3 phosphorylation, nuclear translocation and DNA-binding as compared to either IL-6 or FN-adhesion alone in four MM cell lines. STAT3 phosphorylation was increased in cells adhered to FN in an IL-6 dose dependent manner. Electrophoretic mobility shift assay demonstrated a parallel 3-fold increase in STAT3/DNA complexes in cells adhered to FN relative to cells in suspension. To further characterize the receptor proximal affects of FN adhesion on IL-6 signaling we immunoprecipitated the IL-6R complex with antisera to gp130. Immunoprecipitation of gp130 revealed enhanced tyrosine phosphorylation of the gp130/Jak family complexes following stimulation FN-adhered RPMI 8226 MM cells with IL-6. Consistent with increased phosphorylation of the receptor complex, increased levels of phospho-STAT3 were identified associated with gp130 under co-stimulatory conditions relative to IL-6 or FN adhesion alone. Interestingly, immunoprecipitation with gp130 antibodies also revealed an association between STAT3 (non-phosphorylated) and gp130 in the absence of IL-6 stimulation in cells adhered to FN. These results suggest that adhesion to FN facilitates an IL-6-independent association between gp130 and STAT3, resulting in enhanced STAT3 signaling. Taken together, these data demonstrate a novel mechanism by which collaborative signaling by β1 integrin and gp130 confer an increased survival advantage to MM cells.


Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 1359-1359
Author(s):  
Ana A Tula-Sanchez ◽  
Aaron Havas ◽  
Peter Alonge ◽  
Mary E Klein ◽  
Taralyn Y Rogers ◽  
...  

Abstract Abstract 1359 Diffuse large B-cell lymphoma (DLBCL) is the most common type of Non-Hodgkin Lymphoma (NHL) throughout the world. DLBCL is an aggressive, heterogeneous disease with two major recognized cell-of-origin subtypes: “germinal center” (GCB) and “activated B-cell like” (ABC), the latter having the worse prognosis. Overall, DLBCL remains fatal for about 30% patients due to relapse or lack of response to initial therapy. Resistant/relapsed DLBCL patients could benefit from the addition of new promising antiproliferative drugs, such as histone deacetylase inhibitors (HDACIs), to current chemotherapy regimens. So far, Vorinostat and Romidepsin, two structurally different HDACIs, have been approved for the treatment of hematological cancers. Despite their proven antiproliferative, pro-apoptotic effects, response to these drugs against DLBCL in clinical trials have been variable, ranging from complete/partial responses to stable disease to no response. The mechanisms of action of these drugs are still poorly understood, mainly because the function of their target deacetylases are cell context-specific. Therefore, characterization of the specific anticancer mechanisms of action of HDACIs in DLBCL could potentially lead to development of novel combinatorial drug regimens effective against resistant/relapsed DLBCL patients. To define HDACI action in DLBCL, we treated DLBCL-derived cell lines with PXD101, (Belinostat); a hydroxamate HDACI, like Vorinostat. We demonstrated that PXD101 is able to produce 24h growth inhibition (IC50) at submicromolar concentrations regardless of the DLBCL subtype. The 24h IC50values were used in all the subsequent experiments. Cell cycle and apoptosis analysis by flow cytometry indicated that PXD101 produces cytotoxic effects on two of the GCB cell lines; DB and OCILY19 underwent G2/M cell cycle arrest at 24 hours followed by apoptosis at 48 and 72 hours of treatment. Immunoblotting of PARP and caspase-3 cleavage further confirmed apoptosis. More importantly, when cells were treated for only 8 hours with PXD101 and then the drug was removed for 24 hours, cells showed apoptosis rates similar to those observed with 48h of continuous treatment; suggesting that once that these cell lines are exposed to the drug they rapidly commit to cell death. Thus, we have classified the DB and OCILY19 cell lines as models for sensitivity to the apoptotic effects of HDACI. In contrast, PXD101 induced cytostatic effects on the GCB cell line SUDHL4 and ABC cell lines U2932 and SUDHL8. All three cell lines showed G1 phase cell cycle arrest with little apoptosis. The G1 arrest is reversible after 48 hours of drug removal. Because of the lack of cell death and the reversibility of cell cycle arrest, we have classified these cell lines as models of HDACI resistance. Previous studies have shown that induction of p21 is responsible for G1 arrest in cells treated with HDACIs. Western blot analysis showed that none of the cell lines, except U2932, express p21, but upon PXD101, p21 protein levels were induced at 24, 48 and 72 hours of PXD101 treatment in SUDHL4 and U2932. In contrast, p21 was induced to a lesser extent in OCILY19 and DB, but its expression was not sustained beyond 24 hours of treatment. Since we also observed a corresponding loss in Rb phosphorylation, we tested the effect of PXD101 on cyclin dependent kinase 2 (CDK2) activity. This enzyme complex is responsible for entry into S phase and is inhibited by association with p21. In all three resistant cell lines CDK2 activity was reduced after only 24 hours of treatment with PXD101. The loss in activity was correlated with increased association with p21, as determined by immunoprecipitation. These results indicate that sustained upregulation of p21 by HDACIs such as PXD101 plays a role in bringing about G1 arrest that may protect DLBCL cells from apoptosis. Combined treatment with therapeutics that prevent p21 upregulation and G1 arrest may work synergistically with HDACIs to trigger apoptosis in HDACI-resistant cell lines. To that end, we have begun analysis of the cyclin-dependent kinase inhibitor, flavopiridol, and have shown that it prevents both p21 upregulation and G1 arrest in the HDACi-resistant DLBCL cell lines. Studies to measure synergism with PXD101 in bringing about cell death are currently underway. Disclosures: No relevant conflicts of interest to declare.


Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 5004-5004
Author(s):  
Yuliya Linhares ◽  
Jade Dardine ◽  
Siavash Kurdistani

Abstract Abstract 5004 Introduction: Amiloride is an FDA approved potassium-sparing diuretic which targets Na+/H+ exchanger isoform 1 (NHE1). NHE1 is responsible for the regulation of the intracellular pH, as well as cell-cycle and apoptosis. In supra-pharmacologic concentrations, amiloride non-specifically inhibits protein kinases. Recent study demonstrated that proapoptotic effect of amiloride in CML cell lines is linked to the modulation of the alternative splicing of Bcl-x, HIPK3, and BCR/ABL genes and is independent of pHi. Here, we demonstrate that pharmacologic doses of amiloride preferentially induce growth inhibition, cell cycle arrest and apoptosis in Flt3-ITD positive acute myeloid leukemia cell lines as compared to Bcr-Abl positive leukemia cell line. Our data suggests that amiloride may have an effect on Flt3 signaling and that its treatment potential for Flt3-ITD positive acute myeloid leukemia needs to be explored. Methods: MV4-11, MOLM13 and K562 cells lines in log-phase growth were used for the experiments. Analysis of the baseline Flt3 expression and phosphorylation status was assessed via Flt3 immunoprecipitation and Western blotting for Flt3 and phosphotyrosine. Cells were incubated with various amiloride concentrations; equal volume dilutions of DMSO were used for control. Cell counting and trypan blue exclusion viability was performed on TC10 Bio-Rad automated cell counter. The cell cycle analysis was performed applying propidium iodide staining. To assess for apoptosis and cell death, we used annexin V/PI staining kit and flow cytometry. Results: MOLM13 and MV4-11 cell lines carry activating Flt3-ITD mutation. We confirmed the expression and constituative activation of Flt3 in MOLM13 and MV4-11 cells with Western blotting. Flt3 protein was not detectable in K562 cell line. Amiloride at 0.025 mM and 0.05 mM completely inhibited the growth of MV4-11 cells after 24 hrs of treatment with no significant increase in total or live cell numbers at 72 hrs, but only mildly affected K562 cell proliferation. While the above amiloride concentrations caused cell death in MV4-11 and MOLM13 cell lines, there was no increased cell death in K562 cells. Incubation of MOLM13 and MV4-11 cell lines with 0.05 mM amiloride for 20 hrs induced cell cycle arrest. In MV4-11 cell line, the proportion of S phase cells after amiloride treatment was 15.4% (SD=5.4%) as compared to 31.3% (SD=1.4%) in control. MOLM13 cell line demonstrated 15.3% (SD=4.7%) of cells in S after amiloride treatment as compared to 35.3% (SD=2.4%) cells in S phase in control treatment. In K562 cell line, there was less effect with 52% (SD=4.2%) of cells in S phase in control as compared to 37% (SD=8.9%) in amiloride treatment. MV4-11 and MOLM 13 cell lines were more sensitive than K562 cells to amiloride induced apoptosis with 28.8% (control 12.7%) of MV4-11 cells, 11.4% (control 7.4%) of MOLM13 cells, and 11.4% (control 8.6%) of K562 cells being apoptotic after 20 hr treatment with 0.05mM amiloride. At 72 hrs of amiloride treatment 34% (control 1.5%) of MV4-11 cells, 17% (control 5%) of MOLM13 cells and 11% of K562 cells (control 8.9%) were apoptotic. Amiloride had similar effect on the number of dead cells with no increase in total cell death in K562 cell line. Upon treatment with increasing amiloride concentrations, there was dose-dependent increase in cell death and apoptosis in all three cell lines with K562 line showing relative resistance to amiloride. Discussion: Our results demonstrate that amiloride induces cell cycle arrest and inhibits proliferation of Flt3-ITD positive cell lines MV4-11 and MOLM13 as well as K562 cell line at a pharmacologic concentration of 0.05 mM. Both, cell cycle arrest and antiproliferative effect are more pronounced in Flt3-ITD positive cells lines while it is mild in Bcr-Abl positive K562 cell line. Pharmacologic doses of amiloride induce cell death and apoptosis in Flt3-ITD positive cell lines but not in K562 cell line. Both, Bcr-Abl and Flt3 signaling stimulates proliferation and inhibits apoptosis in myeloid leukemia cells. Our study suggests that amiloride may induce cell cycle arrest and apoptosis via modulating Flt3 signaling cascade. We are currently investigating the effects of amiloride on Flt3 phosphorylation. In conclusion, our data suggests that amiloride presents a potential treatment option for Flt3-ITD positive acute myeloid leukemia. Disclosures: No relevant conflicts of interest to declare.


2020 ◽  
Vol 474 (1-2) ◽  
pp. 113-123
Author(s):  
Małgorzata Zielińska-Przyjemska ◽  
Mariusz Kaczmarek ◽  
Violetta Krajka-Kuźniak ◽  
Marcin Wierzchowski ◽  
Wanda Baer-Dubowska

Abstract The present study aimed to evaluate the cytotoxicity and its mechanism of five synthetic methoxy stilbenes, namely 3,4,4ʹ-trimethoxy, 3,4,2ʹ-trimethoxy, 3,4,2ʹ,4ʹ-tetramethoxy, 3,4,2ʹ,6ʹ-tetramethoxy, and 3,4,2ʹ,4ʹ,6ʹ-pentamethoxy-trans-stilbenes (MS), in comparison with resveratrol (RSV). Human promyelocytic (HL-60) and monocytic leukemia (THP-1) cells were treated with the tested compounds for 24 h, and cytotoxicity, cell cycle distribution, and apoptosis were evaluated. Significant differences were found in the susceptibility of these cell lines to all stilbenes, including RSV. The THP-1 cells were more resistant to cytotoxic activity of these compounds than HL-60 cells. Among the tested stilbenes, 3,4,4ʹ-tri-MS and 3,4,2ʹ,4ʹ-tetra-MS exhibited higher cytotoxicity toward both cell lines than RSV and the other methoxy stilbenes. This activity might be related to cell cycle arrest at the G2/M phase and induction of apoptosis. In this regard, 3,4,4ʹ-tri-MS and 3,4,2ʹ,4ʹ-tetra-MS at highest concentrations increased the p53 protein level particularly in HL-60 cells. Moreover, treatment with these derivatives increased the ratio of the proapoptotic Bax protein to the antiapoptotic Bcl-xl protein, suggesting the induction of apoptosis through the intrinsic mitochondrial pathway in both cell lines. Further studies are required to fully elucidate the mechanism of these activities.


2018 ◽  
Vol 120 (6) ◽  
pp. 9608-9623 ◽  
Author(s):  
Wagner D. Vital ◽  
Heron F. V. Torquato ◽  
Larissa de Oliveira Passos Jesus ◽  
Wagner Alves de Souza Judice ◽  
Maria Fátima das G. F. da Silva ◽  
...  

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