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1.
Ann Clin Lab Sci ; 50(5): 674-680, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33067215

RESUMO

OBJECTIVE: This study aimed to establish a new external quality assessment (EQA) of chromosomal karyotype analysis. METHODS: Chimeric assembly A1 was established by collecting chimeric chromosome images prepared artificially from chromosomally abnormal amniocytes remaining after prenatal diagnosis. Chimeric assembly B1 and nonchimeric assembly C1 were constructed through the collection of chimeric and nonchimeric chromosome images from prenatal diagnosis, respectively. Then, chromosome images were selected randomly from assemblies A1, B1, or C1 to send to 20 technicians via email to verify the validity of a new EQA of chromosomal karyotype analysis. RESULTS: According to the EQA of 20 technicians, 47,XX,+mar from assembly A was easily misdiagnosed as 47,XX,+19 or 47,XXY, and 45,XX,t(13;22) (q10;q10) was misdiagnosed as 45,XX,13S+,-22. The total misdiagnosis rate was 3.8%. For assembly B, 46,X,+mar and 46,X,idic(Y) were easily misdiagnosed as 46,XY and 46,X,+mar, respectively. In addition, some testers missed 47,XXX in 47,XXX[2]/46,XX[48], as well as 47,XX,+18 in 46,XX [47]/47,XX,+18[3], and 45,X and 47,XXX in 46,XX[47]/45,X[2]/47,XXX[1]. The total misdiagnosis rate was 4.2%. All karyo-types from assembly C were correctly diagnosed, although incorrect descriptions used for 4% of cases. CONCLUSION: The quality of chromosome karyotype analysis can be comprehensively evaluated by a new EQA based on assembly A1 or B1.


Assuntos
Processamento de Imagem Assistida por Computador , Cariotipagem , Diagnóstico Pré-Natal , Feminino , Humanos , Gravidez , China , Transtornos Cromossômicos/diagnóstico , Processamento de Imagem Assistida por Computador/métodos , Cariótipo , Cariotipagem/métodos , Diagnóstico Pré-Natal/métodos , Controle de Qualidade
2.
Clin Lab ; 66(9)2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32902232

RESUMO

BACKGROUND: The shortage of quality-control materials caused by non-renewable utilization of rare disease samples is the key factor to limit the quality control of prenatal molecular diagnosis. This study aimed to prepare aneuploid amniocyte lines for the development of quality control cells for fluorescence in situ hybridization (FISH)-mediated detection of aneuploidy. METHODS: Recombinant SV40LTag-pcDNA3.1(-) vectors were transfected into 47,XY,+18 amniotic fluid cells with the use of liposomes. After culturing, these cells were mixed with primary amniocytes with the karyotype 46,XY to prepare four groups of chimeric quality control cells comprising recombinant cells with the karyotypes 47,XY,+18 and primary cells with 46,XY, with theoretical ratios of 47,XY,+18 cells at 5%, 10%, 20%, and 40%. Subsequently, the chimeric quality control cells were tested as clinical samples by three technicians to examine their feasibility for use as internal quality controls (IQC) for FISH detection. RESULTS: After being immortalized by the SV40 large T antigen gene (SV40LT), these aneuploid amniocytes can be cultured indefinitely to prepare chimeric quality control cells. The actual ratio of the 47,XY,+18 cells was identified by FISH to be 1.5 ± 1.1%, 10.3 ± 1.0%, 19.9 ± 0.4%, and 40.8 ± 0.3%, respectively, and the fluorescence signals of chromosomes 13, 18, 21, X, and Y in these cells were consistent with that of the primary cells. CONCLUSIONS: The present study may resolve the shortage of quality control cells in the prenatal detection of chromosomal aneuploidy and may provide a foundation for IQC-based detection in FISH.


Assuntos
Aneuploidia , Diagnóstico Pré-Natal , Feminino , Humanos , Hibridização in Situ Fluorescente , Cariotipagem , Gravidez , Controle de Qualidade
3.
Med Phys ; 43(7): 4349, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27370150

RESUMO

PURPOSE: Lower radiation tolerance of the whole liver hinders dose escalations of stereotactic body radiation therapy (SBRT) in hepatocellular carcinoma (HCC) treatment. This study was conducted to define the exact doses that result in radiation-induced liver disease (RILD) as well as to determine dose constraints for the critical organs at risk (OARs) in mice; these parameters are still undefined in HCC SBRT. METHODS: This study consisted of two phases. In the primary phase, mice treated with helical tomotherapy-based SBRT were stratified according to escalating radiation doses to the livers. The pathological differences, signs [such as mouse performance status (MPS)], and serum aspartate aminotransferase (AST)/alanine aminotransferase (ALT)/albumin levels were observed. Radiation-induced disease severities of the OARs were scored using systematic evaluation standards. In the validation phase in humans, 13 patients with HCC who had undergone radiotherapy before hepatectomy were enrolled to validate RILD pathological changes in a mouse study. RESULTS: The evaluation criteria of the mouse liver radiotherapy-related signs were as follows: MPS ≥ 2.0 ± 0.52, AST/ALT ≥ 589.2 ± 118.5/137.4 ± 15.3 U/L, serum albumin ≤ 16.8 ± 2.29 g/L. The preliminary dose constraints of the OARs were also obtained, such as those for the liver (average dose ≤ 26.36 ± 1.71 Gy) and gastrointestinal tract (maximum dose ≤ 22.63 Gy). Mouse RILD models were able to be developed when the livers were irradiated with average doses of ≥31.76 ± 1.94 Gy (single fraction). RILD pathological changes in mice have also been validated in HCC patients. CONCLUSIONS: Mouse RILD models could be developed with SBRT based on the dose constraints for the OARs and evaluation criteria of mouse liver radiotherapy-related signs, and the authors' results favor the study of further approaches to treat HCC with SBRT.


Assuntos
Hepatopatias/etiologia , Fígado/efeitos da radiação , Lesões Experimentais por Radiação , Radiocirurgia/efeitos adversos , Radioterapia de Intensidade Modulada/efeitos adversos , Adulto , Idoso , Alanina Transaminase/sangue , Albuminas/metabolismo , Animais , Aspartato Aminotransferases/sangue , Carcinoma Hepatocelular/radioterapia , Carcinoma Hepatocelular/cirurgia , Relação Dose-Resposta à Radiação , Feminino , Trato Gastrointestinal/efeitos da radiação , Humanos , Fígado/patologia , Fígado/cirurgia , Hepatopatias/sangue , Hepatopatias/patologia , Hepatopatias/terapia , Masculino , Camundongos Endogâmicos ICR , Pessoa de Meia-Idade , Órgãos em Risco , Lesões Experimentais por Radiação/sangue , Radiocirurgia/métodos , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Radioterapia de Intensidade Modulada/métodos , Distribuição Aleatória
4.
FEBS J ; 282(3): 579-94, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25475121

RESUMO

Deregulated microRNAs and their roles in carcinogenesis and cancer progression have attracted much attention. In previous studies conducted in our laboratory, the Illumina Solexa massively parallel signature sequencing of miRNomes in nontumor and hepatocellular carcinoma (HCC) tissues revealed that miR-486-5p was significantly downregulated in HCC, but its role in HCC development remains unknown. In this study, miR-486-5p levels in HCC tissues and matched control tissues, and in seven HCC cell lines (QGY-7701, QGY-7703, QGY-7404, SMMC-7721, Huh7, HepG2, and PCL/PRF/5) and human normal liver cells (HL-7702), were tested by real-time quantitative RT-PCR. We found that the level of miR-486-5p was significantly decreased in HCC tissue and in all seven HCC cell lines. Overexpression of miR-486-5p markedly suppressed HCC cell proliferation, migration and invasion in vitro, and inhibited HCC growth in vivo. Mechanistically, miR-486-5p was confirmed to directly target PIK3R1 expression, thereby suppressing phosphatidylinositol 3-kinase-AKT pathway activation, by dual luciferase reporter assay and real-time quantitative RT-PCR and western blot analysis. In addition, PIK3R1 knockdown mimicked the effects of miR-486-5p overexpression by inhibiting HCC growth, migration, and invasion. Furthermore, correlation analysis, Kaplan-Meier estimates and Cox proportional hazard models showed an inverse correlation between miR-486-5p and PIK3R1, as well as a shorter time to recurrence after HCC resection, in patients with lower miR-486-5p expression. Hence, we conclude that miR-486-5p, which is frequently downregulated in HCC, inhibits HCC progression by targeting PIK3R1 and phosphatidylinositol 3-kinase-AKT activation.


Assuntos
Carcinoma Hepatocelular/metabolismo , Proliferação de Células/fisiologia , Neoplasias Hepáticas/metabolismo , MicroRNAs/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Animais , Western Blotting , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Movimento Celular/fisiologia , Proliferação de Células/genética , Classe Ia de Fosfatidilinositol 3-Quinase , Humanos , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , MicroRNAs/genética , Fosfatidilinositol 3-Quinase/metabolismo , Fosfatidilinositol 3-Quinases/genética , Células Tumorais Cultivadas
5.
Chem Biol Interact ; 203(1): 212-6, 2013 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-22960160

RESUMO

We are investigating treatments for cocaine abuse based on viral gene transfer of a cocaine hydrolase (CocH) derived from human butyrylcholinesterase, which can reduce cocaine-stimulated locomotion and cocaine-primed reinstatement of drug-seeking behavior in rats for many months. Here, in mice, we explored the possibility that anti-cocaine antibodies can complement the actions of CocH to reduce cocaine uptake in brain and block centrally-evoked locomotor stimulation. Direct injections of test proteins showed that CocH (0.3 or 1mg/kg) was effective by itself in reducing drug levels in plasma and brain of mice given cocaine (10mg/kg, s.c., or 20mg/kg, i.p). Administration of cocaine antibody per se at a low dose (8 mg/kg, i.p.) exerted little effect on cocaine distribution. However, a higher dose of antibody (12 mg/kg) caused peripheral trapping (increased plasma drug levels), which led to increased cocaine metabolism by CocH, as evidenced by a 6-fold rise in plasma benzoic acid. Behavioral tests with small doses of CocH and antibody (1 and 8 mg/kg, respectively) showed that neither agent alone reduced mouse locomotor activity triggered by a very large cocaine dose (100mg/kg, i.p.). However, dual treatment completely suppressed the locomotor stimulation. Altogether, we found cooperative and possibly synergistic actions that warrant further exploration of dual therapies for treatment of cocaine abuse.


Assuntos
Butirilcolinesterase/metabolismo , Cocaína/antagonistas & inibidores , Cocaína/imunologia , Hidrolases/metabolismo , Animais , Anticorpos/administração & dosagem , Encéfalo , Butirilcolinesterase/genética , Cocaína/metabolismo , Cocaína/toxicidade , Transtornos Relacionados ao Uso de Cocaína/fisiopatologia , Transtornos Relacionados ao Uso de Cocaína/terapia , Comportamento de Procura de Droga , Humanos , Hidrolases/genética , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Atividade Motora , Ratos , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Vacinas/administração & dosagem
7.
PLoS One ; 6(7): e21697, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21750723

RESUMO

Engagement of T-cell immunoglobulin mucin (Tim)-1 on T cells with its ligand, Tim-4, on antigen presenting cells delivers positive costimulatory signals to T cells. However, the molecular mechanisms for Tim-1-mediated regulation of T-cell activation and differentiation are relatively poorly understood. Here we investigated the role of Tim-1 in T-cell responses and allograft rejection using recombinant human Tim-1 extracellular domain and IgG1-Fc fusion proteins (Tim-1-Fc). In vitro assays confirmed that Tim-1-Fc selectively binds to CD4(+) effector T cells, but not dendritic cells or natural regulatory T cells (nTregs). Tim-1-Fc was able to inhibit the responses of purified CD4(+) T cells that do not express Tim-4 to stimulation by anti-CD3/CD28 mAbs, and this inhibition was associated with reduced AKT and ERK1/2 phosphorylation, but it had no influence on nTregs. Moreover, Tim-1-Fc inhibited the proliferation of CD4(+) T cells stimulated by allogeneic dendritic cells. Treatment of recipient mice with Tim-1-Fc significantly prolonged cardiac allograft survival in a fully MHC-mismatched strain combination, which was associated with impaired Th1 response and preserved Th2 and nTregs function. Importantly, the frequency of Foxp3(+) cells in splenic CD4(+) T cells was increased, thus shifting the balance toward regulators, even though Tim-1-Fc did not induce Foxp3 expression in CD4(+)CD25(-) T cells directly. These results indicate that Tim-1-Fc can inhibit T-cell responses through an unknown Tim-1 binding partner on T cells, and it is a promising immunosuppressive agent for preventing allograft rejection.


Assuntos
Rejeição de Enxerto/imunologia , Fragmentos Fc das Imunoglobulinas/imunologia , Glicoproteínas de Membrana/imunologia , Receptores Virais/imunologia , Proteínas Recombinantes de Fusão/imunologia , Linfócitos T/imunologia , Animais , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Proliferação de Células/efeitos dos fármacos , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Citometria de Fluxo , Fatores de Transcrição Forkhead/imunologia , Fatores de Transcrição Forkhead/metabolismo , Rejeição de Enxerto/prevenção & controle , Transplante de Coração/imunologia , Receptor Celular 1 do Vírus da Hepatite A , Fragmentos Fc das Imunoglobulinas/genética , Fragmentos Fc das Imunoglobulinas/metabolismo , Masculino , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Proteína Quinase 1 Ativada por Mitógeno/imunologia , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/imunologia , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Fosforilação/efeitos dos fármacos , Ligação Proteica , Proteínas Proto-Oncogênicas c-akt/imunologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores Virais/genética , Receptores Virais/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Recombinantes de Fusão/farmacologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Linfócitos T/metabolismo , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Transplante Homólogo
8.
Zhong Xi Yi Jie He Xue Bao ; 8(2): 145-51, 2010 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-20141737

RESUMO

OBJECTIVE: To explore the effects of astilbin on the maturation and immunologic function of mouse bone marrow-derived dendritic cells (DCs). METHODS: Mouse bone marrow cells were cultured with recombinant mouse granulocyte-macrophage colony-stimulating factor and interleukin-4 (IL-4) for 5 days to get immature DCs (imDCs), then the imDCs was cultured in the presence of 1 microg/mL lipopolysaccharide (LPS) or LPS (1 microg/mL) plus astilbin (25, 50, 100 microg/mL) for 48 h. Then, the cells were harvested, and the apoptosis, immunophenotypes and antigen phagocytosis capability of imDCs in LPS, and low-, medium- and high-dose astilbin groups were analyzed by flow cytometry. Contents of p40 subunit of interleukin-12 (IL-12p40) in the supernatants were detected with enzyme-linked immunosorbent assay (ELISA). The stimulatory activity of the harvested cells on allogeneic T cells in mixed lymphocyte reactions (MLR) was tested by incorporation of 3H-thymidine, and the contents of IL-2, IL-4, IL-10 and interferon-gamma (INF-gamma) in the supernatants of MLR were examined by ELISA. RESULTS: At the concentrations of 25 to 100 microg/mL, astilbin exhibited no toxicity on co-cultured DCs. Compared with the lipopolysaccharide, low-, medium- and high-dose astilbin could decrease the expression levels of major histocompatibility complex-Ia (MHC-Ia), CD40, CD80 and CD86 molecules in DCs. DCs in the low-, medium- and high-dose astilbin groups exhibited weaker capabilities for antigen phagocytosis and less contents of IL-12p40 in the supernatants than in the LPS group. Furthermore, low-, medium- and high-dose astilbin showed weak activities in stimulating the proliferation of allogeneic T cells as compared with the LPS (P<0.05). Compared with the LPS, low-, medium- and high-dose astilbin could decrease IL-2 and INF-mu secretion from T cells in MLR but had no effect on IL-10 secretion. CONCLUSION: Astilbin can inhibit maturation of mouse bone marrow-derived DCs with dose-dependent effect and exert negative effects on immunologic function of the DCs.


Assuntos
Células Dendríticas/efeitos dos fármacos , Células Dendríticas/imunologia , Medicamentos de Ervas Chinesas/farmacologia , Flavonóis/farmacologia , Animais , Células da Medula Óssea/citologia , Células Cultivadas , Células Dendríticas/citologia , Camundongos , Camundongos Endogâmicos BALB C
9.
Zhong Xi Yi Jie He Xue Bao ; 7(8): 753-7, 2009 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-19671414

RESUMO

OBJECTIVE: To investigate the protective effects of astilbin on renal ischemia-reperfusion (IR) injury in rats. METHODS: Twenty-four male SD rats, two months old, were randomly allocated into three groups: sham-operated group (n=8), untreated group (n=8) and astilbin group (n=8). Rats in the untreated group and the astilbin group underwent temporary renal artery occlusion to induce IR injury. The rats in the astilbin group were intraperitoneally injected with 12 mg/mL astilbin at a dose of 30 mg/kg from 3 day before IR injury until to be sacrificed once per day, and rats in the untreated group were injected with equal volume of normal saline at the same time. After 6-hour reperfusion, blood urea nitrogen (BUN) and serum creatinine (SCr) and histological changes of the renal tissues were detected to evaluate renal injury. Expressions of monocyte chemoattractant protein-1 (MCP-1) mRNA and protein in the renal tissues and the serum contents of interleukin-6 (IL-6) and IL-1beta were also measured with semi-quantitative reverse transcription-polymerase chain reaction, Western blotting or enzyme-linked immunosorbent assay. RESULTS: Compared with the untreated group, BUN and SCr levels were significantly decreased in the astilbin group after 6-hour reperfusion (P<0.01), and similar results were also found in histological examination. The expressions of MCP-1 mRNA and protein in renal tissues in the astilbin group were lower than those in the untreated group. The serum contents of IL-6 and IL-1beta were decreased in the astilbin group as compared with the untreated group (P<0.01). CONCLUSION: Astilbin can ameliorate kidney IR injury in rats by inhibiting the production of chemokine MCP-1 and cytokines IL-6 and IL-1beta.


Assuntos
Flavonóis/farmacologia , Rim/irrigação sanguínea , Substâncias Protetoras/farmacologia , Traumatismo por Reperfusão/tratamento farmacológico , Animais , Quimiocina CCL2/genética , Quimiocina CCL2/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Interleucina-1beta/sangue , Interleucina-6/sangue , Masculino , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley
10.
Can Vet J ; 47(9): 902-6, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17017658

RESUMO

The clinical signs of a disorder in yaks (Bos grunniens), known locally as "swayback ailment," in the Qing Hai-Tibetan Plateau are described. The purpose of this study is to investigate the possibility that swayback ailment is iron (Fe)-induced copper (Cu) deficiency. The mean concentrations of Cu in soil and forage from affected areas and unaffected areas are similar and within the normal ranges. The mean concentrations of Cu in blood and hair from the affected yaks was significantly lower (P < 0.01) than that in unaffected yaks. The mean concentrations of Fe in soil and forage were significantly higher (P < 0.01) in affected than in unaffected areas. Affected yaks showed a hypochromic microcytic anemia and a low level of ceruloplasmin. Oral administration of copper sulphate prevented and cured the disease. We conclude that "swayback disorder" of yaks is caused by secondary Cu deficiency, mainly due to the high Fe content in forage.


Assuntos
Ração Animal/efeitos adversos , Doenças dos Bovinos/diagnóstico , Sulfato de Cobre/uso terapêutico , Cobre/deficiência , Ferro/intoxicação , Animais , Bovinos , Doenças dos Bovinos/tratamento farmacológico , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/metabolismo , Ceruloplasmina/metabolismo , China/epidemiologia , Cobre/sangue , Cobre/metabolismo , Cabelo/química , Ferro/metabolismo , Distribuição Aleatória , Solo/análise , Resultado do Tratamento
11.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 35(1): 18-22, 2006 01.
Artigo em Chinês | MEDLINE | ID: mdl-16470915

RESUMO

OBJECTIVE: To observe the effects of kaempferol and quercetin on the activity of cytochrome P450 in rat hepatocytes. METHODS: Primarily cultured rat hepatocytes were exposed to kaempferol or quercetin in concentrations of 0.1, 1, 10 micromol/L for 12 h, 24 h and 48 h. Hepatocytes CYP isoemzymes-erythromycin N-demethylase (ERND) and aminopyrine N-demethylase (ADM) activities were determined by Nash methods. Erythromycin (10 micromol/L) was used as positive control and DMSO(0.1%) as solvent control. RESULTS: Kaempferol and quercetin inhibited ENRD activity in a dose-and time-dependent manner. In dose-response study, the ENRD activities in kaempferol (0.1,1 and 10 micromol/L) treated groups were (0.088+/-0.008), (0.074+/-0.006) and (0.041+/-0.003)micromol/(mg.min(-1)), respectively. ENRD activity in quercetin treated groups at the same concentrations were (0.082+/-0.007), (0.063+/-0.007) and (0.034+/-0.005) micromol/(mg.min(-1)), respectively. In time-courses study, the ENRD activity exposed to 10 micromol/L kaempferol or quercetin for 12 h and 48 h were (0.053+/-0.006) and (0.037+/-0.007) micromol/(mg.min(-1)), or (0.067+/-0.005) and (0.032+/-0.004) micromol/(mg.min(-1)). ADM activity was inhibited only by kaempferol in 10 mol/L at 24 h, but was not significantly altered by quercetin at any concentration tested. CONCLUSION: In the present condition, kaempferol and quercetin act as potential CYP3A4 inhibitors as they can significantly inhibit ENRD in primarily cultured rat hepatocytes.


Assuntos
Citocromo P-450 CYP3A/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Quempferóis/farmacologia , Neoplasias Hepáticas/enzimologia , Quercetina/farmacologia , Aminopirina N-Desmetilase/metabolismo , Animais , Carcinoma Hepatocelular/enzimologia , Relação Dose-Resposta a Droga , Hepatócitos/metabolismo , Neoplasias Hepáticas/patologia , Ratos , Células Tumorais Cultivadas
12.
Photochem Photobiol ; 81(2): 306-13, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15560738

RESUMO

Photodynamic therapy (PDT) is a novel cancer therapy inducing irreversible photodamage to tumor tissue via photosensitizer-mediated oxidative cytotoxicity. The cellular and molecular responses associated with PDT are only partially understood. We have reported previously the generation of several photosensitizer-specific PDT-resistant cell variants of HT29 human colon adenocarcinoma cells by selecting cells from sequential PDT treatment using different photosensitizers. In this report, we describe the use of messenger RNA (mRNA) differential display to identify genes that were differentially expressed in the parental HT29 cells compared with their resistant variants. In comparison with parental HT29 cells, mRNA expression was increased in the PDT-resistant cell variants for BNIP3, estrogen receptor-binding fragment-associated gene 9, Myh-1c, cytoplasmic dynein light chain 1, small membrane protein I and differential dependent protein. In contrast, expression in the PDT-resistant variants was downregulated for NNX3, human HepG2 3' region Mbol complementary DNA, glutamate dehydrogenase, hepatoma-derived growth factor and the mitochondrial genes coding for 16S ribosomal RNA (rRNA) and nicotinamide adenine dinucleotide (NADH) dehydrogenase subunit 4. The reduction for mitochondrial 16S rRNA in the PDT-resistant variants was confirmed by Northern blotting, and the elevated expression of the proapoptotic BNIP3 in the PDT-resistant variants was confirmed by Northern and Western blotting analysis. We also examined the expression of some additional apoptosis-regulating genes using Western blotting. We show an increased expression of Bcl-2 and heat shock protein 27 and a downregulation of Bax in the PDT-resistant variants. In addition, the mutant p53 levels in the parental HT29 cells were reduced substantially in the PDT-resistant variants. We suggest that the altered expression in several mitochondrial and apoptosis-regulating genes contributes to PDT resistance.


Assuntos
Apoptose/fisiologia , Neoplasias do Colo/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Mitocôndrias/metabolismo , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Apoptose/efeitos dos fármacos , Apoptose/genética , Neoplasias do Colo/metabolismo , Resistencia a Medicamentos Antineoplásicos , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Proteínas de Choque Térmico HSP27 , Células HT29 , Proteínas de Choque Térmico/efeitos dos fármacos , Proteínas de Choque Térmico/genética , Humanos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/genética , Chaperonas Moleculares , Dados de Sequência Molecular , Proteínas de Neoplasias/efeitos dos fármacos , Proteínas de Neoplasias/genética , Proteínas Proto-Oncogênicas c-bcl-2/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/genética , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteína Supressora de Tumor p53/efeitos dos fármacos , Proteína Supressora de Tumor p53/genética , Proteína X Associada a bcl-2
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