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1.
Front Genet ; 14: 1282834, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37900182

RESUMO

Next-Generation Sequencing (NGS) has transformed clinical histocompatibility laboratories through its capacity to provide accurate, high-throughput, high-resolution typing of Human Leukocyte Antigen (HLA) genes, which is critical for transplant safety and success. As this technology becomes widely used for clinical genotyping, histocompatibility laboratories now have an increased capability to identify novel HLA alleles that previously would not be detected using traditional genotyping methods. Standard guidelines for the clinical verification and reporting of novelties in the era of NGS are greatly needed. Here, we describe the experience of a clinical histocompatibility laboratory's use of NGS for HLA genotyping and its management of novel alleles detected in an ethnically-diverse population of British Columbia, Canada. Over a period of 18 months, 3,450 clinical samples collected for the purpose of solid organ or hematopoietic stem cell transplantation were sequenced using NGS. Overall, 29 unique novel alleles were identified at a rate of ∼1.6 per month. The majority of novelties (52%) were detected in the alpha chains of class II (HLA-DQA1 and -DPA1). Novelties were found in all 11 HLA classical genes except for HLA-DRB3, -DRB4, and -DQB1. All novelties were single nucleotide polymorphisms, where more than half led to an amino acid change, and one resulted in a premature stop codon. Missense mutations were evaluated for changes in their amino acid properties to assess the potential effect on the novel HLA protein. All novelties identified were confirmed independently at another accredited HLA laboratory using a different NGS assay and platform to ensure validity in the reporting of novelties. The novel alleles were submitted to the Immuno Polymorphism Database-Immunogenetics/HLA (IPD-IMGT/HLA) for official allele name designation and inclusion in future database releases. A nationwide survey involving all Canadian HLA laboratories confirmed the common occurrence of novel allele detection but identified a wide variability in the assessment and reporting of novelties. In summary, a considerable proportion of novel alleles were identified in routine clinical testing. We propose a framework for the standardization of policies on the clinical management of novel alleles and inclusion in proficiency testing programs in the era of NGS-based HLA genotyping.

2.
Biometals ; 32(6): 909-921, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31624972

RESUMO

Breast cancer is a leading cause of cancer-related death in women; however, chemotherapy of breast cancer is often hindered by dose-limiting toxicities, demonstrating the need for less toxic approaches to treatment. Since the rapid growth and metabolism of breast cancer cells results in an increased requirement for iron, withdrawal of bioavailable iron using highly selective iron chelators has been suggested to represent a new approach to breast cancer treatment. Here we show that the recently developed iron-binding polymer DIBI inhibited the growth of five different breast cancer cell lines (SK-BR3, MDA-MB-468, MDA-MB-231, MCF-7, and T47D). In cultures of MDA-MB-468 breast cancer cells, which were most sensitive to DIBI-mediated growth inhibition, iron withdrawal was associated with increased expression of transferrin receptor 1 and ferritin H mRNA but decreased expression of ferroportin mRNA. MDA-MB-468 cells that were exposed to DIBI experienced double-strand DNA breaks during the S phase of the cell cycle. DNA damage was not mediated by reactive oxygen species (ROS) since DIBI-treated MDA-MB-468 cells exhibited a reduction in intracellular ROS. DIBI-treated MDA-MB-468 cells also showed increased sensitivity to growth inhibition by the chemotherapeutic drugs cisplatin, doxorubicin, and 4-hydroperoxy cyclophosphamide (active metabolite of cyclophosphamide). Combination treatment of MDA-MB-468 cells with DIBI and cisplatin caused greater DNA damage than either treatment alone, which was also associated with an increase in apoptotic cell death. Taken together, these findings suggest that DIBI-mediated iron withdrawal may enhance the effect of chemotherapeutic agents used in breast cancer treatment.


Assuntos
Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Dano ao DNA , Quelantes de Ferro/farmacologia , Polímeros/farmacologia , Piridinas/farmacologia , Piridonas/farmacologia , Fase S/efeitos dos fármacos , Antineoplásicos/química , Neoplasias da Mama/metabolismo , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Quelantes de Ferro/química , Polímeros/química , Piridinas/química , Piridonas/química , Relação Estrutura-Atividade , Células Tumorais Cultivadas
3.
Exp Mol Pathol ; 107: 10-22, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30660598

RESUMO

Breast cancer is the most prevalent cancer diagnosis in women, with triple-negative and human epidermal growth factor 2 (HER2)-enriched advanced breast cancers having the poorest prognoses. The morbidity and mortality associated with advanced disease, as well as the emergence of multi-drug resistant variants, highlights the urgency to develop novel therapeutic agents. Artesunate (ART) is a semi-synthetic derivative of artemisinin from the Chinese herb sweet wormwood. ART is widely used in the treatment of malaria and is well tolerated by patients. Importantly, ART also has anti-cancer activities and may therefore represent a less toxic alternative to conventional chemotherapy. In this study, we demonstrate a dose- and time-dependent inhibitory effect of ART on the growth of triple-negative MDA-MB-468 and HER2-enriched SK-BR-3 breast cancer cells, which was the result of both anti-proliferative and cytotoxic activities. ART inhibited breast cancer cell proliferation via a reactive oxygen species (ROS)-dependent G2/M arrest and ROS-independent G1 arrest. ART-treated MDA-MB-468 and SK-BR-3 cells also experienced apoptotic cell death, which was both ROS- and iron-dependent. ART-induced oxidative stress caused the loss of mitochondrial outer membrane integrity and damage to the cellular DNA of MDA-MB-468 and SK-BR-3 cells. In addition, exposure to low-dose ART sensitized MDA-MB-468 and SK-BR-3 cells to chemotherapeutic drugs. On the basis of our findings, we suggest that ART may have clinical utility in the treatment of triple-negative and HER2-enriched breast cancers.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Artesunato/farmacologia , Neoplasias da Mama/patologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Antimaláricos/farmacologia , Linhagem Celular Tumoral , Feminino , Humanos , Receptor ErbB-2 , Neoplasias de Mama Triplo Negativas/patologia
4.
Food Chem Toxicol ; 118: 154-167, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29742465

RESUMO

Myricetin is a dietary phytochemical with anticancer activity; however, the effect of myricetin on breast cancer cells remains unclear. Here, we show that myricetin inhibited the growth of triple-negative breast cancer (TNBC) cells but was less inhibitory for normal cells. The effect of myricetin was comparable to epigallocatechin gallate and doxorubicin, and greater than resveratrol and cisplatin. Myricetin-treated TNBC cells showed evidence of early and late apoptosis/necrosis, which was associated with intracellular reactive oxygen species (ROS) accumulation, extracellular regulated kinase 1/2 and p38 mitogen-activated protein kinase activation, mitochondrial membrane destabilization and cytochrome c release, and double-strand DNA breaks. The antioxidant N-acetyl-cysteine protected myricetin-treated TNBC cells from cytotoxicity due to DNA damage. Myricetin also induced hydrogen peroxide (H2O2) production in cell-free culture medium, as well as in the presence of TNBC cells and normal cells. In addition, deferiprone-mediated inhibition of intracellular ROS generation via the iron-dependent Fenton reaction and inhibition of extracellular ROS accumulation with superoxide dismutase plus catalase prevented myricetin-induced cytotoxicity in TNBC cell cultures. We conclude that the cytotoxic effect of myricetin on TNBC cells was due to oxidative stress initiated by extracellular H2O2 formed by autoxidation of myricetin, leading to intracellular ROS production via the Fenton reaction.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Flavonoides/farmacologia , Peróxido de Hidrogênio/farmacologia , Ferro/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Acetilcisteína/farmacologia , Catalase/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Dano ao DNA , Feminino , Humanos , Mitocôndrias/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Neoplasias de Mama Triplo Negativas/enzimologia , Neoplasias de Mama Triplo Negativas/metabolismo
5.
Mol Ther Oncolytics ; 6: 80-89, 2017 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-28856238

RESUMO

The reovirus fusion-associated small transmembrane (FAST) proteins are the smallest known viral fusogens (∼100-150 amino acids) and efficiently induce cell-cell fusion and syncytium formation in multiple cell types. Syncytium formation enhances cell-cell virus transmission and may also induce immunogenic cell death, a form of apoptosis that stimulates immune recognition of tumor cells. These properties suggest that FAST proteins might serve to enhance oncolytic virotherapy. The oncolytic activity of recombinant VSVΔM51 (an interferon-sensitive vesicular stomatitis virus [VSV] mutant) encoding the p14 FAST protein (VSV-p14) was compared with a similar construct encoding GFP (VSV-GFP) in cell culture and syngeneic BALB/c tumor models. Compared with VSV-GFP, VSV-p14 exhibited increased oncolytic activity against MCF-7 and 4T1 breast cancer spheroids in culture and reduced primary 4T1 breast tumor growth in vivo. VSV-p14 prolonged survival in both primary and metastatic 4T1 breast cancer models, and in a CT26 metastatic colon cancer model. As with VSV-GFP, VSV-p14 preferentially replicated in vivo in tumors and was cleared rapidly from other sites. Furthermore, VSV-p14 increased the numbers of activated splenic CD4, CD8, natural killer (NK), and natural killer T (NKT) cells, and increased the number of activated CD4 and CD8 cells in tumors. FAST proteins may therefore provide a multi-pronged approach to improving oncolytic virotherapy via syncytium formation and enhanced immune stimulation.

6.
Mol Carcinog ; 56(1): 75-93, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-26878598

RESUMO

Ovarian cancer is a leading cause of cancer-related death in women and the most lethal gynecological malignancy in the developed world. The morbidity and mortality of ovarian cancer underscore the need for novel treatment options. Artesunate (ART) is a well-tolerated anti-malarial drug that also has anti-cancer activity. In this study, we show that ART inhibited the in vitro growth of a panel of ovarian cancer cell lines, as well as the growth of ovarian cancer cells isolated from patients. Moreover, ART decreased tumor growth in vivo in a mouse model of ovarian cancer. ART-treated ovarian cancer cells showed a strong induction of reactive oxygen species (ROS) and reduced proliferation. ROS-dependent cell cycle arrest occurred in the G2/M phase whereas ROS-independent cell cycle arrest occurred in the G1 phase, depending on the concentration of ART to which ovarian cancer cells were exposed. The anti-proliferative effect of ART was associated with altered expression of several key cell cycle regulatory proteins, including cyclin D3, E2F-1, and p21, as well as inhibition of mechanistic target of rapamycin signaling. Exposure of ovarian cancer cells to higher concentrations of ART resulted in ROS-dependent DNA damage and cell death. Pretreatment of ovarian cancer cells with a pan-caspase inhibitor or ferroptosis inhibitor decreased but did not completely eliminate ART-mediated cytotoxicity, suggesting the involvement of both caspase-dependent and caspase-independent pathways of killing. These data show that ART has potent anti-proliferative and cytotoxic effects on ovarian cancer cells, and may therefore be useful in the treatment of ovarian cancer. © 2016 Wiley Periodicals, Inc.


Assuntos
Antimaláricos/uso terapêutico , Antineoplásicos/uso terapêutico , Artemisininas/uso terapêutico , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Neoplasias Ovarianas/tratamento farmacológico , Ovário/efeitos dos fármacos , Animais , Antimaláricos/farmacologia , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Artemisininas/farmacologia , Artesunato , Linhagem Celular Tumoral , Feminino , Fase G2/efeitos dos fármacos , Humanos , Camundongos Endogâmicos C57BL , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Ovário/metabolismo , Ovário/patologia , Espécies Reativas de Oxigênio/metabolismo
7.
Phytomedicine ; 23(12): 1494-1503, 2016 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-27765370

RESUMO

BACKGROUND: Many plant-derived chemicals have been studied for their potential benefits in ailments including inflammation, cancer, neurodegeneration, and cardiovascular disease. The health benefits of phytochemicals are often attributed to the targeting of reactive oxygen species (ROS). However, it is not always clear whether these agents act directly as antioxidants to remove ROS, or whether they act indirectly by blocking ROS production by enzymes such as NADPH oxidase (NOX) enzymes, or by influencing the expression of cellular pro- and anti- oxidants. HYPOTHESIS/PURPOSE: Here we evaluate the pro- and anti-oxidant and NOX-inhibiting qualities of four phytochemicals: celastrol, resveratrol, apigenin, and piperine. STUDY DESIGN: This work was done using the H661 cell line expressing little or no NOX, modified H661 cells expressing NOX1 and its subunits, and an EBV-transformed B-lymphoblastoid cell line expressing endogenous NOX2. ROS were measured using Amplex Red and nitroblue tetrazolium assays. In addition, direct ROS scavenging of hydrogen peroxide or superoxide generated were measured using Amplex Red and methyl cypridina luciferin analog (MCLA). RESULTS: Of the four plant-derived compounds evaluated, only celastrol displayed NOX inhibitory activities, while celastrol and resveratrol both displayed ROS scavenging activity. Very little impact on ROS was observed with apigenin, or piperine. CONCLUSION: The results of this study reveal the differences that exist between cell-free and intracellular pro-oxidant and antioxidant activities of several plant-derived compounds.


Assuntos
Alcaloides/farmacologia , Antioxidantes/farmacologia , Apigenina/farmacologia , Benzodioxóis/farmacologia , NADPH Oxidases/antagonistas & inibidores , Piperidinas/farmacologia , Extratos Vegetais/farmacologia , Alcamidas Poli-Insaturadas/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Estilbenos/farmacologia , Linhagem Celular , Humanos , Peróxido de Hidrogênio , NADP/antagonistas & inibidores , Oxirredução , Triterpenos Pentacíclicos , Resveratrol , Triterpenos/metabolismo , Triterpenos/farmacologia
8.
J Cell Biochem ; 117(8): 1913-25, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26755433

RESUMO

Fisetin (3,3',4',7-tetrahydroxyflavone), a flavonoid found in a number of fruits and vegetables, has diverse biological activities, including cytotoxic effects on cancer cells. In this study, we investigated the effect of fisetin on triple-negative breast cancer (TNBC) cells. TNBC has a poorer prognosis than other types of breast cancer and treatment options for this disease are limited. Fisetin inhibited the growth of MDA-MB-468 and MDA-MB-231 TNBC cells, as well as their ability to form colonies, without substantially affecting the growth of non-malignant cells. In addition, fisetin inhibited the growth of estrogen receptor-bearing MCF-7 breast cancer cells and human epidermal growth factor receptor 2-overexpressing SK-BR-3 breast cancer cells. Fisetin inhibited TNBC cell division and induced apoptosis, which was associated with mitochondrial membrane permeabilization and the activation of caspase-9 and caspase-8, as well as the cleavage of poly(ADP-ribose) polymerase-1. Induction of caspase-dependent apoptosis by fisetin was confirmed by reduced killing of TNBC cells in the presence of the pan-caspase inhibitors Z-VAD-FMK and BOC-D-FMK. Decreased phosphorylation of histone H3 at serine 10 in fisetin-treated TNBC cells at G2/M phase of the cell cycle suggested that fisetin-induced apoptosis was the result of Aurora B kinase inhibition. Interestingly, the cytotoxic effect of cisplatin, 5-fluorouracil, and 4-hydroxycyclophosphamide metabolite of cyclophosphamide on TNBC cells was increased in the presence of fisetin. These findings suggest that further investigation of fisetin is warranted for possible use in the management of TNBC. J. Cell. Biochem. 117: 1913-1925, 2016. © 2016 Wiley Periodicals, Inc.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Caspase 8/metabolismo , Caspase 9/metabolismo , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Citotoxinas/farmacologia , Flavonoides/farmacologia , Proteínas de Neoplasias/metabolismo , Neoplasias da Mama/enzimologia , Feminino , Flavonóis , Humanos
9.
Exp Mol Pathol ; 99(2): 262-70, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26210486

RESUMO

Since iron uptake is essential for cell growth, rapidly dividing cancer cells are sensitive to iron depletion. To explore the effect of iron withdrawal on cancer cell growth, mouse and human mammary carcinoma cells (4T1 and MDA-MB-468, respectively) and mouse and human fibrosarcoma cells (L929 and HT1080, respectively) were cultured in the absence or presence of DIBI, a novel iron-chelating polymer containing hydroxypyridinone iron-ligand functionality. Cell growth was measured by a colorimetric assay for cell metabolic activity. DIBI-treated 4T1, MDA-MB-468, L929 and HT1080 cells, as well as their normal counterparts, showed a dose- and time-dependent reduction in growth that was selective for human cancer cells and mouse fibrosarcoma cells. The inhibitory effect of DIBI on fibrosarcoma and mammary carcinoma cell growth was reversed by addition of exogenous iron in the form of iron (III) citrate, confirming the iron selectivity of DIBI and that its inhibitory activity was iron-related. Fibrosarcoma and mammary carcinoma cell growth inhibition by DIBI was associated with S-phase cell cycle arrest and low to moderate levels of cell death by apoptosis. Consistent with apoptosis induction following DIBI-mediated iron withdrawal, fibrosarcoma and mammary carcinoma cells exhibited mitochondrial membrane permeabilization. A comparison of DIBI to other iron chelators showed that DIBI was superior to deferiprone and similar to or better than deferoxamine for inhibition of fibrosarcoma and mammary carcinoma cell growth. These findings suggest that iron withdrawal from the tumor microenvironment with a selective and potent iron chelator such as DIBI may prevent or inhibit tumor progression.


Assuntos
Apoptose/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Proliferação de Células/efeitos dos fármacos , Fibrossarcoma/tratamento farmacológico , Quelantes de Ferro/farmacologia , Deficiências de Ferro , Neoplasias Mamárias Animais/tratamento farmacológico , Animais , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Feminino , Fibrossarcoma/metabolismo , Fibrossarcoma/patologia , Humanos , Neoplasias Mamárias Animais/metabolismo , Neoplasias Mamárias Animais/patologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Células Tumorais Cultivadas
10.
PLoS One ; 10(7): e0133385, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26177198

RESUMO

Tumor progression and the immune response are intricately linked. While it is known that cancers alter macrophage inflammatory responses to promote tumor progression, little is known regarding how cancers affect macrophage-dependent innate host defense. In this study, murine bone-marrow-derived macrophages (BMDM) were exposed to murine carcinoma-conditioned media prior to assessment of the macrophage inflammatory response. BMDMs exposed to 4T1 mammary carcinoma-conditioned medium demonstrated enhanced production of pro-inflammatory cytokines tumor necrosis factor α, interleukin-6, and CCL2 in response to lipopolysaccharide (LPS) while production of interleukin-10 remained unchanged. The increased LPS-induced production of pro-inflammatory cytokines was transient and correlated with enhanced cytokine production in response to other Toll-like receptor agonists, including peptidoglycan and flagellin. In addition, 4T1-conditioned BMDMs exhibited strengthened LPS-induced nitric oxide production and enhanced phagocytosis of Escherichia coli. 4T1-mediated augmentation of macrophage responses to LPS was partially dependent on the NFκB pathway, macrophage-colony stimulating factor, and actin polymerization, as well as the presence of 4T1-secreted extracellular vesicles. Furthermore, peritoneal macrophages obtained from 4T1 tumor-bearing mice displayed enhanced pro-inflammatory cytokine production in response to LPS. These results suggest that uptake of 4T1-secreted factors and actin-mediated ingestion of 4T1-secreted exosomes by macrophages cause a transient enhancement of innate inflammatory responses. Mammary carcinoma-mediated regulation of innate immunity may have significant implications for our understanding of host defense and cancer progression.


Assuntos
Imunidade Inata , Inflamação/imunologia , Inflamação/patologia , Macrófagos/imunologia , Actinas/metabolismo , Animais , Linhagem Celular Tumoral , Quimiocinas/biossíntese , Meios de Cultivo Condicionados/farmacologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/metabolismo , Flagelina/farmacologia , Imunidade Inata/efeitos dos fármacos , Mediadores da Inflamação/metabolismo , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos Peritoneais/efeitos dos fármacos , Macrófagos Peritoneais/metabolismo , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Nitritos/metabolismo , Oligodesoxirribonucleotídeos/farmacologia , Peptidoglicano/farmacologia , Fagocitose/efeitos dos fármacos , Polimerização/efeitos dos fármacos
11.
Toxicol Lett ; 234(1): 1-12, 2015 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-25655587

RESUMO

Piperine, a pungent alkaloid found in the fruits of black pepper plants, has diverse physiological effects, including the ability to inhibit immune cell-mediated inflammation. Since the cytokine interleukin-2 (IL-2) is essential for the clonal expansion and differentiation of T lymphocytes, we investigated the effect of piperine on IL-2 signaling in IL-2-dependent mouse CTLL-2 T lymphocytes. Tritiated-thymidine incorporation assays and flow cytometric analysis of Oregon Green 488-stained cells showed that piperine inhibited IL-2-driven T lymphocyte proliferation; however, piperine did not cause T lymphocytes to die or decrease their expression of the high affinity IL-2 receptor, as determined by flow cytometry. Western blot analysis showed that piperine blocked the IL-2-induced phosphorylation of signal transducer and activator of transcription (STAT) 3 and STAT5 without affecting the upstream phosphorylation of Janus kinase (JAK) 1 and JAK3. In addition, piperine inhibited the IL-2-induced phosphorylation of extracellular signal-regulated kinase 1/2 and Akt, which are signaling molecules that regulate cell cycle progression. Piperine also suppressed the expression of cyclin-dependent kinase (Cdk) 1, Cdk4, Cdk6, cyclin B, cyclin D2, and Cdc25c protein phosphatase by IL-2-stimulated T lymphocytes, indicating G0/G1 and G2/M cell cycle arrest. Piperine-mediated inhibition of IL-2 signaling and cell cycle progression in CTLL-2 T lymphocytes suggests that piperine should be further investigated in animal models as a possible natural source treatment for T lymphocyte-mediated transplant rejection and autoimmune disease.


Assuntos
Alcaloides/farmacologia , Benzodioxóis/farmacologia , Interleucina-2/antagonistas & inibidores , Piperidinas/farmacologia , Alcamidas Poli-Insaturadas/farmacologia , Linfócitos T/efeitos dos fármacos , Animais , Western Blotting , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Quinases Ciclina-Dependentes/metabolismo , Citometria de Fluxo , Janus Quinase 3/metabolismo , Camundongos , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fator de Transcrição STAT3/metabolismo , Fator de Transcrição STAT5/metabolismo , Transdução de Sinais , Linfócitos T/citologia
12.
Cancer Lett ; 357(1): 129-140, 2015 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-25444919

RESUMO

Piperine, an alkaloid from black pepper, is reported to have anticancer activities. In this study, we investigated the effect of piperine on the growth and motility of triple-negative breast cancer (TNBC) cells. Piperine inhibited the in vitro growth of TNBC cells, as well as hormone-dependent breast cancer cells, without affecting normal mammary epithelial cell growth. Exposure to piperine decreased the percentage of TNBC cells in the G2 phase of the cell cycle. In addition, G1- and G2-associated protein expression was decreased and p21(Waf1/Cip1) expression was increased in piperine-treated TNBC cells. Piperine also inhibited survival-promoting Akt activation in TNBC cells and caused caspase-dependent apoptosis via the mitochondrial pathway. Interestingly, combined treatment with piperine and γ radiation was more cytotoxic for TNBC cells than γ radiation alone. The in vitro migration of piperine-treated TNBC cells was impaired and expression of matrix metalloproteinase-2 and -9 mRNA was decreased, suggesting an antimetastatic effect by piperine. Finally, intratumoral administration of piperine inhibited the growth of TNBC xenografts in immune-deficient mice. Taken together, these findings suggest that piperine may be useful in the treatment of TNBC.


Assuntos
Alcaloides/farmacologia , Benzodioxóis/farmacologia , Piperidinas/farmacologia , Alcamidas Poli-Insaturadas/farmacologia , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Células MCF-7 , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Transdução de Sinais , Ensaios Antitumorais Modelo de Xenoenxerto
13.
Nutr Cancer ; 66(3): 408-18, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24579801

RESUMO

Thymoquinone (TQ) from black caraway seeds has several anticancer activities; however, its effect on triple-negative breast cancer (TNBC) cells that lack functional tumor suppressor p53 is not known. Here, we explored the growth inhibitory effect of TQ on 2 TNBC cell lines with mutant p53. Cell metabolism assays showed that TQ inhibited TNBC cell growth without affecting normal cell growth. Flow cytometric analyses of TQ-treated TNBC cells showed G1 phase cell cycle arrest and apoptosis characterized by the loss of mitochondrial membrane integrity. Western blots of lysates from TQ-treated TNBC cells showed cytochrome c and apoptosis-inducing factor in the cytoplasm, as well as caspase-9 activation consistent with the mitochondrial pathway of apoptosis. Caspase-8 was also activated in TQ-treated TNBC cells, although the mechanism of activation is not clear at this time. Importantly, TQ-induced apoptosis was only partially inhibited by zVAD-fmk, indicating a role for caspase-independent effector molecules. Poly(ADP-ribose) polymerase cleavage and increased γH2AX, as well as reduced Akt phosphorylation and decreased expression of X-linked inhibitor of apoptosis, were evident in TQ-treated cells. Finally, TQ enhanced cisplatin- and docetaxel-induced cytotoxicity. These findings suggest that TQ could be useful in the management of TNBC, even when functional p53 is absent.


Assuntos
Apoptose/efeitos dos fármacos , Benzoquinonas/farmacologia , Carum/química , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Genes p53 , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Antineoplásicos Fitogênicos/farmacologia , Caspases/metabolismo , Linhagem Celular Tumoral/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mutação , Sementes/química , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia
14.
Cancer Lett ; 297(1): 1-8, 2010 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-20472336

RESUMO

Curcumin from the rhizome of theCurcuma longa plant has chemopreventative activity and inhibits the growth of neoplastic cells. Since p53 has been suggested to be important for anticancer activity by curcumin, we investigated curcumin-induced cytotoxicity in cultures of p53(+/+) and p53(-/-) HCT-116 colon cancer cells, as well as mutant p53 HT-29 colon cancer cells. Curcumin killed wild-type p53 HCT-116 cells and mutant p53 HT-29 cells in a dose- and time-dependent manner. In addition, curcumin-treated p53(+/+) HCT-116 cells and mutant p53 HT-29 cells showed upregulation of total and activated p53, as well as increased expression of p53-regulated p21, PUMA (p53 upregulated modulator of apoptosis), and Bax; however, an equivalent cytotoxic effect by curcumin was observed in p53(+/+) and p53(-/-) HCT-116 cells, demonstrating that curcumin-induced cytotoxicity was independent of p53 status. Similar results were obtained when the cytotoxic effect of curcumin was assessed in wild-type p53 HCT-116 cells after siRNA-mediated p53 knockdown. Chromatin condensation, poly (ADP-ribose) polymerase-1 cleavage and reduced pro-caspase-3 levels in curcumin-treated p53(+/+) and p53(-/-) HCT-116 cells suggested that curcumin caused apoptosis. In addition, exposure to curcumin resulted in superoxide anion production and phosphorylation of oxidative stress proteins in p53(+/+) and p53(-/-) HCT-116 cells. Collectively, our results indicate that, despite p53 upregulation and activation, curcumin-induced apoptosis in colon cancer cells was independent of p53 status and involved oxidative stress. Curcumin may therefore have therapeutic potential in the management of colon cancer, especially in tumorsthatare resistant to conventional chemotherapydue todefects inp53 expression or function.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias do Colo/patologia , Curcumina/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Superóxidos/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Proteínas Reguladoras de Apoptose/metabolismo , Caspase 3/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Montagem e Desmontagem da Cromatina/efeitos dos fármacos , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Relação Dose-Resposta a Droga , Células HCT116 , Células HT29 , Humanos , Mutação , Fosforilação , Poli(ADP-Ribose) Polimerase-1 , Poli(ADP-Ribose) Polimerases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Interferência de RNA , Fatores de Tempo , Proteína Supressora de Tumor p53/genética , Regulação para Cima , Proteína X Associada a bcl-2/metabolismo
15.
Mol Carcinog ; 49(1): 13-24, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19676105

RESUMO

New cytotoxic agents are urgently needed for the treatment of advanced ovarian cancer because of the poor long-term response of this disease to conventional chemotherapy. Curcumin, obtained from the rhizome of Curcuma longa, has potent anticancer activity; however, the mechanism of curcumin-induced cytotoxicity in ovarian cancer cells remains a mystery. In this study we show that curcumin exhibited time- and dose-dependent cytotoxicity against monolayer cultures of ovarian carcinoma cell lines with differing p53 status (wild-type p53: HEY, OVCA429; mutant p53: OCC1; null p53: SKOV3). In addition, p53 knockdown or p53 inhibition did not diminish curcumin killing of HEY cells, confirming p53-independent cytotoxicity. Curcumin also killed OVCA429, and SKOV3 cells grown as multicellular spheroids. Nuclear condensation and fragmentation, as well as DNA fragmentation and poly (ADP-ribose) polymerase-1 cleavage in curcumin-treated HEY cells, indicated cell death by apoptosis. Procaspase-3, procaspase-8, and procaspase-9 cleavage, in addition to cytochrome c release and Bid cleavage into truncated Bid, revealed that curcumin activated both the extrinsic and intrinsic pathways of apoptosis. Bax expression was unchanged but Bcl-2, survivin, phosphorylated Akt (on serine 473), and total Akt were downregulated in curcumin-treated HEY cells. Curcumin also activated p38 mitogen-activated protein kinase (MAPK) without altering extracellular signal-regulated kinase 1/2 activity. We conclude that p53-independent curcumin-induced apoptosis in ovarian carcinoma cells involves p38 MAPK activation, ablation of prosurvival Akt signaling, and reduced expression of the antiapoptotic proteins Bcl-2 and survivin. These data provide a mechanistic rationale for the potential use of curcumin in the treatment of ovarian cancer.


Assuntos
Apoptose/efeitos dos fármacos , Curcumina/farmacologia , Proteínas Associadas aos Microtúbulos/metabolismo , Proteína Oncogênica v-akt/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Antineoplásicos/farmacologia , Western Blotting , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Regulação para Baixo/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Feminino , Humanos , Proteínas Inibidoras de Apoptose , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Interferência de RNA , Transdução de Sinais/efeitos dos fármacos , Esferoides Celulares/efeitos dos fármacos , Esferoides Celulares/metabolismo , Survivina , Fatores de Tempo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
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