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1.
Int J Cancer ; 145(11): 3078-3088, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31044434

RESUMO

Diffuse large B-cell lymphoma (DLBCL) is up to 17-fold more likely to occur, follows a more aggressive clinical course and frequently presents at advanced stages in HIV infected (+) individuals compared to HIV negative (-) individuals. However, the molecular pathology underpinning the clinical features of DLBCL in HIV(+) patients relative to the general population is poorly understood. We performed a retrospective study examining the transcriptional, genomic and protein expression differences between HIV(+) and HIV(-) germinal center B-cell (GCB) DLBCL cases using digital gene expression analysis, array comparative genomic hybridization (CGH) and immunohistochemistry (IHC). Genes associated with cell cycle progression (CCNA2, CCNB1, CDC25A, E2F1), DNA replication (MCM2, MCM4, MCM7) and DNA damage repair, including eight Fanconi anemia genes (FANCA, FANCD1/BRCA2, FANCE, FANCG, FANCR/RAD51, FANCS/BRCA1, FANCT/UBE2T, FANCV/MAD2L2), were significantly increased in HIV(+) GCB-DLBCL tumors compared to HIV(-) tumors. In contrast, genes associated with cell cycle inhibition (CDKN1A, CDKN1B) as well as apoptosis regulating BCL2 family members (BCL2, BAX, BIM, BMF, PUMA) were significantly decreased in the HIV(+) cohort. BCL2 IHC confirmed this expression. Array CGH data revealed that HIV(+) GCB-DLBCL tumors have fewer copy number variations than their HIV(-) counterparts, indicating enhanced genomic stability. Together, the results show that HIV(+) GCB-DLBCL is a distinct molecular malignancy from HIV(-) GCB-DLBCL; with an increased proliferative capacity, confirmed by Ki67 IHC staining, and enhanced genomic stability, the latter of which is likely related to the enhanced expression of DNA repair genes.


Assuntos
Reparo do DNA , Perfilação da Expressão Gênica/métodos , Instabilidade Genômica , Infecções por HIV/genética , Linfoma Difuso de Grandes Células B/genética , Adulto , Idoso , Hibridização Genômica Comparativa , Feminino , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Humanos , Imuno-Histoquímica , Linfoma Difuso de Grandes Células B/virologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
2.
Artigo em Inglês | MEDLINE | ID: mdl-31033496

RESUMO

Tissue microarrays (TMAs) are important tools to conserve precious tissue resources from increasingly smaller biopsies and to control experimental costs and variation across sample sets. The quality assurance assessment of TMA materials created at centralized biobanks has not been standardized. Herein, we outline 2 processes for the construction of TMAs ("recipient block" and "tape" methods) and the associated preconstruction quality control measures (pathology review, protein and RNA assessment, map creation, and storage conditions) developed by the AIDS Cancer Specimen Resource (ACSR) Network's Science and Technology Core. These steps provide a suggested framework for quality assessment that allows end-users, receiving materials from tissue banks, confidence in their experimental results.

3.
Cancer Biol Ther ; 16(1): 43-51, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25485960

RESUMO

Gemcitabine based treatment is currently a standard first line treatment for patients with advanced pancreatic cancer, however overall survival remains poor, and few options are available for patients that fail gemcitabine based therapy. To identify potential molecular targets in gemcitabine refractory pancreatic cancer, we developed a series of gemcitabine resistant (GR) cell lines. Initial drug exposure selected for an early resistant phenotype that was independent of drug metabolic pathways. Prolonged drug selection pressure after 16 weeks, led to an induction of cytidine deaminase (CDA) and enhanced drug detoxification. Cross resistance profiles demonstrate approximately 100-fold cross resistance to the pyrimidine nucleoside cytarabine, but no resistance to the same in class agents, azacytidine and decitabine. GR cell lines demonstrated a dose dependent collateral hypersensitivity to class I and II histone deacetylase (HDAC) inhibitors and decreased expression of 3 different global heterochromatin marks, as detected by H4K20me3, H3K9me3 and H3K27me3. Cell morphology of the drug resistant cell lines demonstrated a fibroblastic type appearance with loss of cell-cell junctions and an altered microarray expression pattern, using Gene Ontology (GO) annotation, consistent with progression to an invasive phenotype. Of particular note, the gemcitabine resistant cell lines displayed up to a 15 fold increase in invasive potential that directly correlates with the level of gemcitabine resistance. These findings suggest a mechanistic relationship between chemoresistance and metastatic potential in pancreatic carcinoma and provide evidence for molecular pathways that may be exploited to develop therapeutic strategies for refractory pancreatic cancer.


Assuntos
Antimetabólitos Antineoplásicos/farmacologia , Desoxicitidina/análogos & derivados , Resistencia a Medicamentos Antineoplásicos , Inibidores de Histona Desacetilases/farmacologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Movimento Celular/genética , Cromatina/genética , Cromatina/metabolismo , Desoxicitidina/farmacologia , Relação Dose-Resposta a Droga , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica , Histona Desacetilases/metabolismo , Humanos , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Fenótipo
4.
Invest New Drugs ; 31(3): 576-86, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23179338

RESUMO

Deletions or mutations in the tumor suppressor gene DPC4 (deleted in pancreatic carcinoma locus 4) are common in colon and pancreatic cancers. Using the Target-related Affinity Profiling (TRAP) chemical library screening method, a novel agent, UA8967, was selected for further studies because it showed greater potency in DPC4-deleted HCT-116 colon cancer cells. Cytotoxicity studies in six pancreatic cancer cell lines (MiaPaca-2, Panc-1, BxPC3, CF-PAC1, AsPC1, and T3M4), one normal human pancreatic ductal epithelial line (HPDE-6) and the HCT-116 DPC4(+/+) and HCT-116 DPC4(-/-) colon cancer cells showed IC50s ranging from 12-61 µM for exposure times of 72 h. Analysis of schedule dependence showed no advantage for long drug exposure times. There was also no selective inhibition of DNA, RNA or protein synthesis after exposure to UA8967. At 24-48 h, there was an accumulation of cells in G0/G1-phase and a proportionate reduction in S-phase cells. Within 1-6 h of exposure, cells were found to undergo an autophagic response, followed at 24 h by a low level of caspase-independent apoptosis with some necrosis. Because of the relatively non-specific mechanistic effects of UA8967, plasma membrane viability was evaluated using uptake of trypan blue and Sytox® Green dyes, and leakage of LDH. There was a dose dependent increase in Sytox® Green staining, trypan blue uptake and LDH leakage with increasing concentrations of UA8967, suggesting that UA8967 is affecting the plasma membrane. The DPC4(-/-) cells were more sensitive to UA8967 but not to DMSO, suggesting a drug-specific effect on cell membrane integrity.


Assuntos
Antineoplásicos/farmacologia , Indóis/farmacologia , Piperazinas/farmacologia , Proteína Smad4/genética , Ciclo Celular/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Linhagem Celular , Linhagem Celular Tumoral , Membrana Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Humanos , L-Lactato Desidrogenase/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos
5.
Invest New Drugs ; 30(5): 1865-77, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21931968

RESUMO

Chronic inflammation is associated with 25% of all cancers. In the inflammation-cancer axis, prostaglandin E(2) (PGE(2)) is one of the major players. PGE(2) synthases (PGES) are the enzymes downstream of the cyclooxygenases (COXs) in the PGE(2) biosynthesis pathway. Microsomal prostaglandin E(2) synthase 1 (mPGES-1) is inducible by pro-inflammatory stimuli and constitutively expressed in a variety of cancers. The potential role for this enzyme in tumorigenesis has been reported and mPGES-1 represents a novel therapeutic target for cancers. In order to identify novel small molecule inhibitors of mPGES-1, we screened the ChemBridge library and identified 13 compounds as potential hits. These compounds were tested for their ability to bind directly to the enzyme using surface plasmon resonance spectroscopy and to decrease cytokine-stimulated PGE(2) production in various cancer cell lines. We demonstrate that the compound PGE0001 (ChemBridge ID number 5654455) binds to human mPGES-1 recombinant protein with good affinity (K(D) = 21.3 ± 7.8 µM). PGE0001 reduces IL-1ß-induced PGE(2) release in human HCA-7 colon and A549 lung cancer cell lines with EC(50) in the sub-micromolar range. Although PGE0001 may have alternative targets based on the results from in vitro assays, it shows promising effects in vivo. PGE0001 exhibits significant anti-tumor activity in SW837 rectum and A549 lung cancer xenografts in SCID mice. Single injection i.p. of PGE0001 at 100 mg/kg decreases serum PGE(2) levels in mice within 5 h. In summary, our data suggest that the identified compound PGE0001 exerts anti-tumor activity via the inhibition of the PGE(2) synthesis pathway.


Assuntos
Anti-Inflamatórios/farmacologia , Antineoplásicos/farmacologia , Neoplasias Colorretais/tratamento farmacológico , Inflamação/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Animais , Linhagem Celular Tumoral , Neoplasias Colorretais/metabolismo , Dinoprostona/metabolismo , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Células HCT116 , Células HT29 , Humanos , Inflamação/metabolismo , Oxirredutases Intramoleculares/metabolismo , Neoplasias Pulmonares/metabolismo , Camundongos , Camundongos SCID , Microssomos/metabolismo , Prostaglandina-E Sintases , Prostaglandina-Endoperóxido Sintases/metabolismo , Prostaglandinas E/farmacologia , Ressonância de Plasmônio de Superfície
6.
Cancer Chemother Pharmacol ; 69(4): 1039-49, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22186884

RESUMO

PURPOSE: Preclinical studies evaluated the anti-tumor activity and mechanism of action of AMP423, a naphthyl derivative of 2-cyanoaziridine-1-carboxamide with structural similarity to the pro-oxidant anti-tumor agent imexon. METHODS: The cytotoxic potency was evaluated in vitro against a variety of human cancer cell lines. Mechanism-of-action studies were performed in the human 8226/S myeloma cell line and its imexon-resistant variant, 8226/IM10. In vivo activity was evaluated against human myeloma and lymphoma xenografts in SCID mice. Pharmacokinetics and toxicology were investigated in non-tumor-bearing mice. RESULTS: The 72-h IC(50)s for all cell types ranged from 2 to 36 µM, across a wide variety of human cancer cell lines. AMP423 was active in SCID mice bearing 8226/S myeloma and SU-DHL-6 B-cell lymphoma tumors, with a median tumor growth delay (T-C) of 21 days (P = 0.0002) and 5 days (P = 0.004), respectively, and a median tumor growth inhibition (T/C) of 33.3% (P = 0.03) and 82% (P = 0.01), respectively. In non-tumor-bearing mice, AMP423 was not myelosuppressive. Mechanistic studies show that AMP423's mode of cell death is a mixture of necrosis and apoptosis, with generation of reactive oxygen species, inhibition of protein synthesis, and a decrease in reduced sulfhydryl levels, but no alkylation of nucleophiles. Unlike its structural analog imexon, which causes cell cycle arrest in G(2)/M, AMP423 induces the accumulation of cells in S-phase. CONCLUSIONS: AMP423 has pro-oxidant effects similar to imexon, has greater cytotoxic potency in vitro, and has anti-tumor activity in hematologic tumors in vivo.


Assuntos
Antineoplásicos/farmacologia , Aziridinas/farmacologia , Linfoma de Células B/tratamento farmacológico , Mieloma Múltiplo/tratamento farmacológico , Naftalenos/farmacologia , Animais , Antineoplásicos/química , Antineoplásicos/farmacocinética , Aziridinas/química , Aziridinas/farmacocinética , Pontos de Checagem do Ciclo Celular , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Hexanonas/química , Hexanonas/farmacocinética , Hexanonas/farmacologia , Humanos , Linfoma de Células B/metabolismo , Masculino , Camundongos , Camundongos SCID , Mieloma Múltiplo/metabolismo , Naftalenos/química , Naftalenos/farmacocinética , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Cancer Chemother Pharmacol ; 67(1): 183-92, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20339847

RESUMO

PURPOSE: Gemcitabine (GEM) is currently the standard first line treatment for pancreatic cancer; however, the overall survival of patients with this disease remains poor. Imexon is a pro-oxidant small molecule which produced a high response rate in combination with GEM in a phase I trial in pancreatic cancer. In this study, we investigate the combination of GEM with a novel redox-active agent, imexon, in vitro and in vivo. METHODS: Median effect analysis was used for in vitro combination cytotoxicity. The effect of imexon on GEM metabolism and uptake into cells and into DNA and effects on ribonucleotide reductase (RNR) were examined in vitro. The pharmacokinetics and antitumor efficacy of the imexon/GEM combination was evaluated in mouse models. RESULTS: In three human pancreatic cancer lines, there was additivity for the imexon/GEM combination. There was significantly greater efficacy for the drug combination in Panc-1 xenograft tumors. A pharmacokinetic study in mice showed a near doubling in the AUC of imexon when GEM was co-administered, with no effect of imexon on GEM's pharmacokinetic disposition. In vitro, imexon did not alter GEM's metabolism or uptake into DNA, but significantly inhibited RNR, and this effect was greater when combined with GEM. CONCLUSIONS: These results suggest that the interaction between imexon and GEM may be due to complimentary inhibition of RNR plus an enhanced exposure to imexon when the GEM is administered in vivo. This combination is currently being tested in a randomized phase II trial in pancreatic cancer.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias Pancreáticas/tratamento farmacológico , Ribonucleotídeo Redutases/antagonistas & inibidores , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Área Sob a Curva , Linhagem Celular Tumoral , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Sinergismo Farmacológico , Feminino , Hexanonas/administração & dosagem , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos SCID , Neoplasias Pancreáticas/patologia , Ensaios Antitumorais Modelo de Xenoenxerto
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