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1.
Cell Metab ; 28(5): 689-705.e5, 2018 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-30100196

RESUMO

It is clear that obesity increases the risk of many types of cancer, including breast cancer. However, the underlying molecular mechanisms by which obesity is linked to cancer risk remain to be defined. Herein, we report that circulating adipose fatty acid binding protein (A-FABP) promotes obesity-associated breast cancer development. Using clinical samples, we demonstrated that circulating A-FABP levels were significantly increased in obese patients with breast cancer in comparison with those without breast cancer. Circulating A-FABP released by adipose tissue directly targeted mammary tumor cells, enhancing tumor stemness and aggressiveness through activation of the IL-6/STAT3/ALDH1 pathway. Importantly, genetic deletion of A-FABP successfully reduced tumor ALHD1 activation and obesity-associated mammary tumor growth and development in different mouse models. Collectively, these data suggest circulating A-FABP as a new link between obesity and breast cancer risk, thereby revealing A-FABP as a potential new therapeutic target for treatment of obesity-associated cancers.


Assuntos
Neoplasias da Mama/sangue , Neoplasias da Mama/etiologia , Proteínas de Ligação a Ácido Graxo/sangue , Obesidade/complicações , Família Aldeído Desidrogenase 1 , Animais , Biomarcadores Tumorais/sangue , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Modelos Animais de Doenças , Progressão da Doença , Proteínas de Ligação a Ácido Graxo/metabolismo , Feminino , Humanos , Interleucina-6/metabolismo , Isoenzimas/metabolismo , Camundongos Endogâmicos C57BL , Invasividade Neoplásica/patologia , Obesidade/sangue , Obesidade/metabolismo , Obesidade/patologia , Retinal Desidrogenase/metabolismo , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais
2.
Arch Pathol Lab Med ; 138(7): 885-9, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24978914

RESUMO

CONTEXT: Nongynecologic cytology (NGC) practices are expected to expand relative to gynecologic cytology. The College of American Pathologists attempts to track practice patterns in NGC using a self-reported questionnaire. OBJECTIVE: To analyze self-reported laboratory staffing and practices from a 2010 survey relating to NGC specimens, stains, preparation, procedures, and ancillary testing. DESIGN: The "NGC 2010 Demographics and Supplemental Questionnaire: Current Nongynecologic Practices in Cytopathology Laboratories" was mailed to 2059 laboratories. RESULTS: Survey response rate was 51% (1048 of 2059), predominantly from voluntary, nonprofit hospitals, where NGC samples were reviewed in nontraining settings by pathologists without American Board of Pathology Added Qualification in Cytopathology. Cytotechnologists reviewed NGC cases in 67.4% (675 of 1002) of laboratories. The annual mean and median volumes of NGC cases were 1927 and 858, respectively. Laboratories used more than one method to process NGCs; cell-blocks were most frequently used (930 of 1029; 90.4%) and were created with centrifugation to pellet (538 of 961; 56%). Direct smears were second in preparation frequency; discrete staining was preferred to batch staining. Nongynecologic cytology was used for molecular studies in 34.9% (350 of 1002) of laboratories, most commonly for fluorescent in situ hybridization of urine specimens. Flow cytometric immunophenotyping was performed by 55.9% (554 of 991) and immunohistochemistry by 91.9% (911 of 991) of the responding laboratories. Most laboratories (911 of 993; 91.7%) report specimen completion in 2 or fewer days. Cytohistologic correlation was performed by 71.6% (722 of 1008) of the laboratories both concurrently and retrospectively. CONCLUSION: The various parameters examined in the 2010 survey provide a benchmark for future efforts in quality assurance and process improvement in NGC.


Assuntos
Patologia Clínica , Feminino , Humanos , Laboratórios/normas , Laboratórios/estatística & dados numéricos , Masculino , Patologia Clínica/normas , Patologia Clínica/estatística & dados numéricos , Sociedades Médicas , Inquéritos e Questionários , Estados Unidos , Recursos Humanos
3.
Arch Pathol Lab Med ; 138(1): 65-70, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24377813

RESUMO

Context.-Subtyping of non-small cell lung carcinomas (NSCLCs) is necessary for optimal patient management with specific diagnoses triggering specific molecular tests and affecting therapy. Objective.-To assess the accuracy of the participants of the College of American Pathologists Interlaboratory Comparison Program in diagnosing and subtyping NSCLC fine-needle aspiration (FNA) slides, based on morphology alone, considering preparation and participant type and trends over time. Design.-The performance of program participants was reviewed for the 5-year period spanning 2007-2011. Lung FNA challenges with reference diagnoses of adenocarcinoma and squamous cell carcinoma (SCC) were evaluated for diagnostic concordance by using a nonlinear mixed model analysis. Results.-There were 10 493 pathologist and 6378 cytotechnologist responses with concordance rates of 97.4% and 97.9% for malignancy, respectively. Overall concordance rates for subcategorization were 54.6% for adenocarcinoma and 74.9% for SCC. For the exact reference diagnoses, pathologists performed better for adenocarcinoma and cytotechnologists performed better for SCC. Accurate subcategorization of adenocarcinomas significantly increased over time with 31.5% of adenocarcinomas classified as NSCLC in 2007 and 25.5% of adenocarcinomas classified as NSCLC in 2011 (P < .001). In comparing preparation types, modified Giemsa-stained smears showed the lowest overall concordance (46.8%). Modified Giemsa-stained smears with SCCs were the least likely to be accurately subcategorized (36.4%). Conclusions.-Participants are proficient at interpreting NSCLCs as malignant by FNA but are less successful at subcategorization with cytomorphology alone. During the study period, a statistically significant trend was confirmed toward greater accuracy of subcategorization of adenocarcinomas, suggesting that participants are cognizant of the impact that more specific cytomorphologic interpretations have in directing molecular triage and therapy.


Assuntos
Biópsia por Agulha Fina , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Citodiagnóstico/normas , Neoplasias Pulmonares/diagnóstico , Patologia Clínica/normas , Carcinoma Pulmonar de Células não Pequenas/classificação , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Humanos , Neoplasias Pulmonares/classificação , Neoplasias Pulmonares/cirurgia
4.
J Antimicrob Chemother ; 66(7): 1560-6, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21602551

RESUMO

OBJECTIVES: It is widely believed that persistent Mycobacterium tuberculosis inhabits necrotic lung granulomas in humans and that the microenvironmental conditions encountered therein render the bacilli phenotypically tolerant to antibiotics, accounting for the long duration required for successful treatment of tuberculosis (TB). To validate this belief, we directly compared the activity of rifampicin/isoniazid/pyrazinamide (RHZ) against chronic TB infection in guinea pigs, which exhibit caseous granulomas histologically resembling human caseous foci, and in mice, which lack necrotic granulomas. METHODS: Guinea pigs and mice were aerosol-infected with M. tuberculosis CDC1551 and twice weekly treatment with RHZ was started 4 weeks later. Culture-positive relapse was assessed in subgroups of guinea pigs after 3 months and 4 months of treatment. RESULTS: All guinea pig lungs exhibited histological evidence of granulomas with central caseation, while mouse lungs exhibited cellular lesions at the initiation of antibiotic treatment. Guinea pig lungs became culture-negative after 2 months of RHZ given twice weekly at human-equivalent doses. Relapse rates in guinea pigs were 0% (0/10) both after 3 months and 4 months of treatment. In contrast, all mouse lungs remained culture-positive after 4 months of equivalent RHZ exposures. CONCLUSIONS: Caseous necrosis does not reduce the sterilizing activity of the standard antituberculosis regimen of RHZ. Our findings have important implications for the use of alternative animal models in testing novel TB drug regimens and for modelling M. tuberculosis persistence.


Assuntos
Antituberculosos/administração & dosagem , Farmacorresistência Bacteriana , Tratamento Farmacológico/métodos , Mycobacterium tuberculosis/efeitos dos fármacos , Tuberculose/tratamento farmacológico , Animais , Antituberculosos/farmacologia , Modelos Animais de Doenças , Feminino , Cobaias , Camundongos , Camundongos Endogâmicos BALB C , Mycobacterium tuberculosis/isolamento & purificação , Recidiva , Doenças dos Roedores/tratamento farmacológico , Doenças dos Roedores/microbiologia , Doenças dos Roedores/patologia , Tuberculose/microbiologia , Tuberculose/patologia
5.
Antimicrob Agents Chemother ; 55(4): 1527-32, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21282447

RESUMO

Recent in vitro pharmacokinetic data suggest that the currently recommended dose of pyrazinamide may be suboptimal for killing intracellular bacilli in humans. We evaluated a range of pyrazinamide doses against intracellular and extracellular Mycobacterium tuberculosis in chronically infected mice and guinea pigs, respectively. Antibiotics were given five times weekly for 4 weeks beginning 28 days after infection. Human-equivalent doses of isoniazid reduced lung bacterial counts 10-fold in each species. Pyrazinamide given at 1/4 and 1/2 the human-equivalent dose was minimally active, while human-equivalent doses reduced lung bacterial counts by ∼1.0 log(10) in each species. Doubling the human-equivalent dose of pyrazinamide reduced the lung bacillary burden by 1.7 and 3.0 log(10) in mice and guinea pigs, respectively. As in humans and mice, pyrazinamide showed significant synergy with rifampin in guinea pigs. Clinical studies are warranted to investigate the sterilizing activity and tolerability of higher doses of pyrazinamide in combination tuberculosis regimens.


Assuntos
Antituberculosos/uso terapêutico , Pirazinamida/uso terapêutico , Tuberculose/tratamento farmacológico , Animais , Feminino , Cobaias , Pulmão/efeitos dos fármacos , Pulmão/microbiologia , Pulmão/patologia , Camundongos , Tuberculose/microbiologia
6.
Arch Pathol Lab Med ; 134(1): 19-22, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20073599

RESUMO

CONTEXT: The cytomorphology of liquid-based preparations in urine cytology is different than classic slide preparations. OBJECTIVES: To compare the performance of liquid-based preparation specimens to classically prepared urine specimens with a malignant diagnosis in the College of American Pathologists Interlaboratory Comparison Program in Nongynecologic Cytology. DESIGN: Participant responses between 2000 and 2007 for urine specimens with a reference diagnosis of high-grade urothelial carcinoma/carcinoma in situ/dysplasia (HGUCA), squamous cell carcinoma, or adenocarcinoma were evaluated. ThinPrep and SurePath challenges were compared with classic preparations (smears, cytospins) for discordant responses. RESULTS: There were 18 288 pathologist, 11 957 cytotechnologist, and 8086 "laboratory" responses available. Classic preparations comprised 90% (n = 34 551) of urine challenges; 9% (n = 3295) were ThinPrep and 1% (n = 485) were SurePath. Concordance to the general category of "positive-malignant" was seen in 92% of classic preparations, 96.5% of ThinPrep, and 94.6% of SurePath challenges (P < .001). These results were statistically different for the exact reference interpretation of HGUCA (P < .001) but not for adenocarcinoma (P = .22). Cytotechnologists demonstrate statistically better performance for the general category of "positive-malignant" compared with pathologists for all urinary slide types and for the exact reference interpretation of HGUCA (94% versus 91.1%; P < .001) but not adenocarcinoma (96.3% versus 95.8%; P = .77) or squamous cell carcinoma (93.6% versus 87.7%; P = .07). CONCLUSIONS: Liquid-based preparations performed significantly better in urinary cytology challenges when evaluating malignant categories in the College of American Pathologists interlaboratory comparison program. The liquid-based preparation challenges also performed better for the exact reference interpretation of HGUCA, but no difference was observed for adenocarcinoma challenges. Cytotechnologists perform better than pathologists for all slide types, as well as those demonstrating HGUCA. These results suggest that liquid-based preparations facilitate a more accurate diagnosis than conventional preparations.


Assuntos
Técnicas Citológicas/métodos , Patologia Clínica/métodos , Neoplasias da Bexiga Urinária/diagnóstico , Urina/citologia , Adenocarcinoma/diagnóstico , Adenocarcinoma/patologia , Adenocarcinoma/urina , Carcinoma in Situ/diagnóstico , Carcinoma in Situ/patologia , Carcinoma in Situ/urina , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/urina , Diagnóstico Diferencial , Humanos , Sociedades Médicas , Estados Unidos , Neoplasias da Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/urina
7.
Am J Physiol Lung Cell Mol Physiol ; 298(3): L371-81, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20034961

RESUMO

Despite the associated morbidity and mortality, underlying mechanisms leading to the development of acute lung injury (ALI) remain incompletely understood. Frequently, ALI develops in the hospital, coinciding with institution of various therapies, including the use of supplemental oxygen. Although pathological evidence of hyperoxia-induced ALI in humans has yet to be proven, animal studies involving high oxygen concentration reproducibly induce ALI. The potentially injurious role of lower and presumably safer oxygen concentrations has not been well characterized in any species. We hypothesized that in the setting of a preexisting insult to the lung, the addition of moderate-range oxygen can augment lung injury. Our model of low-dose intratracheal LPS (IT LPS) followed by 60% oxygen caused a significant increase in ALI compared with LPS or oxygen alone with increased alveolar neutrophils, histological injury, and epithelial barrier permeability. In the LPS plus oxygen group, regulatory T cell number was reduced, and macrophage activation markers were increased, compared with LPS alone. Antibody-mediated depletion of neutrophils significantly abrogated the observed lung injury for all measured factors. The enhanced presence of alveolar neutrophils in the setting of LPS and oxygen is due, at least in part, to elevated chemokine gradients signaling neutrophils to the alveolar space. We believe these results strongly support an effect of lower concentrations of oxygen to augment the severity of a mild preexisting lung injury and warrants further investigation in both animals and humans.


Assuntos
Lesão Pulmonar/patologia , Oxigênio/farmacologia , Animais , Líquido da Lavagem Broncoalveolar/citologia , Permeabilidade da Membrana Celular/efeitos dos fármacos , Citocinas/metabolismo , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Mediadores da Inflamação/metabolismo , Contagem de Leucócitos , Procedimentos de Redução de Leucócitos , Lipopolissacarídeos/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Neutrófilos/efeitos dos fármacos , Alvéolos Pulmonares/efeitos dos fármacos , Alvéolos Pulmonares/metabolismo
8.
Arch Ophthalmol ; 127(9): 1162-6, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19752425

RESUMO

OBJECTIVE: To develop an animal model of intraocular tuberculosis (TB) with features of pulmonary TB and extrapulmonary dissemination to the eye. METHODS: Hartley strain guinea pigs were infected via an aerosol route with virulent Mycobacterium tuberculosis. One group of guinea pigs was infected with a relatively low bacterial inoculum and received no treatment. A second group of guinea pigs received high-dose infection and were treated with the first-line anti-TB drugs isoniazid, rifampin, and pyrazinamide. Development of ocular TB lesions was documented by histological analysis, acid-fast staining, and real-time polymerase chain reaction for M tuberculosis DNA. RESULTS: Untreated guinea pigs developed pulmonary and extrapulmonary TB. Ocular TB, primarily involving the uvea, developed in 5 of 12 eyes (42%). Uveal granulomatous lesions showed the presence of acid-fast organisms and M tuberculosis DNA. In treated animals, none of the 8 eyes examined revealed the presence of acid-fast organisms; however, there was mild nongranulomatous uveitis in 4 eyes. CONCLUSIONS: Mycobacterium tuberculosis delivered via aerosol to guinea pigs results in extrapulmonary dissemination to the eye. Of significance, intraocular changes in this model include granulomatous inflammation and the presence of acid-fast organisms, as seen in human cases of ocular TB. Clinical Relevance The guinea pig model may provide greater insight into the pathogenesis of intraocular TB and assist in the development of novel modalities to treat this global infectious disease.


Assuntos
Modelos Animais de Doenças , Mycobacterium tuberculosis/patogenicidade , Tuberculose Ocular/microbiologia , Tuberculose Pulmonar/microbiologia , Aerossóis , Animais , Antituberculosos/uso terapêutico , DNA Bacteriano/análise , Cobaias , Isoniazida/uso terapêutico , Pulmão/microbiologia , Pulmão/patologia , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/isolamento & purificação , Reação em Cadeia da Polimerase , Pirazinamida/uso terapêutico , Rifampina/uso terapêutico , Baço/microbiologia , Tuberculose Ocular/tratamento farmacológico , Tuberculose Ocular/patologia , Tuberculose Pulmonar/tratamento farmacológico , Tuberculose Pulmonar/patologia
9.
J Infect Dis ; 200(7): 1136-43, 2009 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-19686043

RESUMO

The marked reduction in the potent early bactericidal activity of isoniazid during the initial phase of antituberculosis (anti-TB) therapy has been attributed not only to the depletion of logarithmically growing bacilli but also to the emergence of isoniazid resistance. We studied the anti-TB activity of isoniazid and its ability to select for drug-resistant mutant strains in guinea pigs, in which the histopathology of TB closely resembles that of human TB. Prior mouse passage did not appear to enhance the virulence of Mycobacterium tuberculosis in guinea pigs. The human-equivalent dose of isoniazid was determined to be 60 mg/kg. Although isoniazid therapy caused rapid killing of bacilli in guinea pig lungs during the first 14 days of administration and rescued guinea pigs from acute death, its activity was dramatically reduced thereafter. This reduction in activity was not associated with the emergence of isoniazid-resistant mutant strains but, rather, with the selection of phenotypically tolerant "persisters."


Assuntos
Antituberculosos/farmacologia , Farmacorresistência Bacteriana , Isoniazida/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Tuberculose/microbiologia , Animais , Cobaias , Pulmão/microbiologia , Pulmão/patologia , Mycobacterium tuberculosis/patogenicidade , Fatores de Tempo , Virulência
10.
J Cataract Refract Surg ; 32(10): 1768-70, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17010884

RESUMO

A 2-month-old child was referred to our clinic for evaluation and management of a luxated lens. Under general anesthesia, an irregularly shaped iris was observed with the presence of a large iris cyst in the anterior chamber. Sector iridectomy with excision of the cyst was performed. Histopathologic examination confirmed the diagnosis of a stromal cyst of the iris. At the 3-year follow-up, there was no evidence of recurrence of the iris cyst or of a secondary cataract. This case report provides evidence that although a primary cyst of the iris stroma is uncommon, it should be considered in the differential diagnosis for an apparent lens luxation.


Assuntos
Cistos/diagnóstico , Doenças da Íris/diagnóstico , Subluxação do Cristalino/diagnóstico , Cistos/cirurgia , Diagnóstico Diferencial , Humanos , Lactente , Iris/patologia , Doenças da Íris/cirurgia , Masculino
11.
Cancer Res ; 65(14): 6228-36, 2005 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-16024624

RESUMO

CaSm (cancer-associated Sm-like) was originally identified based on elevated expression in pancreatic cancer and in several cancer-derived cell lines. CaSm encodes a 133 amino acid protein that contains two Sm motifs found in the common small nuclear RNA proteins and the LSm (like-Sm) family of proteins. Compared with normal human prostate tissue and primary prostate epithelial cells, some primary prostate tumors and prostate cancer-derived cell lines have elevated CaSm expression. Expression of antisense CaSm RNA in DU145 cells results in reduced CaSm protein levels and less transformed phenotype, measured by anchorage-independent growth in vitro and tumor formation in severe combined immunodeficient mice in vivo. Additional data shows that adenoviral delivery of antisense CaSm inhibits the growth of prostate cancer cell lines by altering cell cycle progression, and is associated with reduced expression of cyclin B1 and CDK1 proteins. Consistent with failure of antisense-treated cells to enter mitosis, microarray analysis identified altered expression of NEK2 and nucleophosmin/B23. Although the mechanisms by which CaSm contributes to neoplastic transformation and cellular proliferation are unknown, it has been shown that the yeast homologue (spb8/LSm1) of CaSm is required for 5' to 3' degradation of specific mRNAs. We provide data consistent with a similar role for CaSm in human cells, supporting the hypothesis that elevated CaSm expression observed in cancer leads to destabilization of multiple gene transcripts, contributing to the mutator phenotype of cancer cells.


Assuntos
Transformação Celular Neoplásica/genética , Neoplasias da Próstata/genética , Proteínas Proto-Oncogênicas/biossíntese , RNA Mensageiro/genética , Adenoviridae/genética , Animais , Proteínas de Ciclo Celular/biossíntese , Proteínas de Ciclo Celular/genética , Divisão Celular/genética , Processos de Crescimento Celular/genética , Linhagem Celular Tumoral , Transformação Celular Neoplásica/metabolismo , Inibidor de Quinase Dependente de Ciclina p21 , Fase G2/genética , Expressão Gênica , Humanos , Masculino , Camundongos , Camundongos SCID , Neoplasias da Próstata/metabolismo , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Proteínas Proto-Oncogênicas/genética , RNA Antissenso/genética , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/genética , Proteínas de Ligação a RNA
12.
Cancer Res ; 63(15): 4626-31, 2003 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-12907642

RESUMO

Ets transcription factors control multiple biological processes, including cell proliferation, differentiation, apoptosis, angiogenesis, transformation, and invasion. Pdef is an Ets transcription factor originally identified in prostate tissue. We demonstrate that human Pdef is expressed at high levels primarily in tissues with high epithelial cell content, including prostate, colon, and breast. We also determined that Pdef protein is reduced in human invasive breast cancer and is absent in invasive breast cancer cell lines. We next assessed the functional consequences of these observations. Significantly, expression of Pdef in breast cancer cells leads to inhibition of invasion, migration, and growth. Expression of Pdef also results in the down-regulation of urokinase-type plasminogen activator and activation of the promoter of the tumor suppressor gene, MASPIN: Growth-suppressive effects of Pdef expression are mediated in part by a G(0)-G(1) cell cycle arrest associated with elevated p21 levels. Collectively, these results indicate that Pdef loss may alter the expression of genes controlling progression to invasive breast cancer.


Assuntos
Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Regulação Neoplásica da Expressão Gênica/fisiologia , Fatores de Transcrição/biossíntese , Neoplasias da Mama/genética , Ciclo Celular/fisiologia , Divisão Celular/fisiologia , Movimento Celular/fisiologia , Regulação para Baixo , Humanos , Invasividade Neoplásica , Proteínas Proto-Oncogênicas c-ets , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Fatores de Transcrição/genética , Fatores de Transcrição/fisiologia , Células Tumorais Cultivadas
13.
Int J Oncol ; 22(5): 1033-43, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12684669

RESUMO

DNA mismatch repair (MMR) is involved in the post-replication correction of errors due to misincorporated nucleotides or DNA slippage during DNA synthesis. We previously reported the reduction or loss of MMR protein expression in human prostate cancer cell lines and some primary tumors. In the present report, we further demonstrate the involvement of defects of MMR in the pathogenesis of prostate cancer. Immunohistochemical analysis of 39 formalin-fixed, paraffin-embedded human prostate tumors, showed reduction or absence of MMR protein expression (MLH1, MSH2, PMS2) in the epithelium of prostate tumor foci compared to normal adjacent prostate tissue. The reduction or absence of the PMS2 and MSH2 (but not MLH1) protein was correlated to the differentiation of the tumor. Poorly differentiated tumors showed greater loss of these two proteins than the well differentiated tumors (P<0.05). We previously reported that microsatellite instability was detectable by a beta-galactosidase restoration mutation assay in the prostate cancer cell lines DU145, PC3, LNCaP, p67SV40T, M2182, and M12. In this study, we detected the insertion or deletion of one nucleotide in the mononucleotide repeats located within the coding regions of BAX gene in DU145, and TGFbetaRII in M12 cells. In addition, we used an in vitro model of defective MMR to demonstrate that microsatellite instability can be induced in an otherwise stable cancer cell line by transfection with a dominant negative fragment of PMS2. These results suggest that defects in MMR may result in MSI in the secondary genes in prostate cancer. From these results, we conclude that loss of MMR function can produce MSI and target some secondary genes containing microsatellites in their coding regions. These series of events may play important roles in the development of human prostate cancer.


Assuntos
Adenosina Trifosfatases/genética , Pareamento Incorreto de Bases/genética , Enzimas Reparadoras do DNA , Reparo do DNA/genética , Proteínas de Ligação a DNA/genética , Regulação Neoplásica da Expressão Gênica , Mutação , Proteínas de Neoplasias/genética , Neoplasias da Próstata/genética , Proteínas Proto-Oncogênicas/genética , Proteínas Adaptadoras de Transdução de Sinal , Adenosina Trifosfatases/metabolismo , Sequência de Bases , Proteínas de Transporte , Primers do DNA , Proteínas de Ligação a DNA/metabolismo , Humanos , Imuno-Histoquímica , Masculino , Repetições de Microssatélites , Endonuclease PMS2 de Reparo de Erro de Pareamento , Proteína 1 Homóloga a MutL , Proteína 2 Homóloga a MutS , Proteínas Nucleares , Reação em Cadeia da Polimerase , Neoplasias da Próstata/patologia , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Recombinantes/metabolismo , Transfecção , Células Tumorais Cultivadas
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