RESUMO
AIMS: Amyotrophic lateral sclerosis (ALS) is a chronic neurodegenerative disease characterized by progressive loss of motor neurons, muscle weakness, spasticity, paralysis and death usually within 2-5 years of onset. Neuroinflammation is a hallmark of ALS pathology characterized by activation of glial cells, which respond by upregulating small heat shock proteins (HSPBs), but the exact underlying pathological mechanisms are still largely unknown. Here, we investigated the association between ALS disease duration, lower motor neuron loss, TARDNA-binding protein 43 (TDP-43) pathology, neuroinflammation and HSPB expression. METHODS: With immunohistochemistry, we examined HSPB1, HSPB5, HSPB6, HSPB8 and HSP16.2 expression in cervical, thoracic and sacral spinal cord regions in 12 ALS cases, seven with short disease duration (SDD), five with moderate disease duration (MDD), and ten age-matched controls. Expression was quantified using ImageJ to examine HSP expression, motor neuron numbers, microglial and astrocyte density and phosphorylated TDP-43 (pTDP-43+) inclusions. RESULTS: SDD was associated with elevated HSPB5 and 8 expression in lateral tract astrocytes, while HSP16.2 expression was increased in astrocytes in MDD cases. SDD cases had higher numbers of motor neurons and microglial activation than MDD cases, but similar levels of motor neurons with pTDP-43+ inclusions. CONCLUSIONS: Increased expression of several HSPBs in lateral column astrocytes suggests that astrocytes play a role in the pathogenesis of ALS. SDD is associated with increased microgliosis, HSPB5 and 8 expression in astrocytes, and only minor changes in motor neuron loss. This suggests that the interaction between motor neurons, microglia and astrocytes determines neuronal fate and functional decline in ALS.
Assuntos
Esclerose Lateral Amiotrófica/patologia , Astrócitos/metabolismo , Proteínas de Choque Térmico/metabolismo , Microglia/metabolismo , Idoso , Idoso de 80 Anos ou mais , Esclerose Lateral Amiotrófica/metabolismo , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neurônios Motores/metabolismo , Neurônios Motores/patologia , Medula Espinal/metabolismo , Medula Espinal/patologiaRESUMO
BACKGROUND: Patients presenting with peritoneal metastases (PM) of colorectal cancer (CRC) can be curatively treated with cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC). Angiogenesis is under control of multiple molecules of which HIF1a, SDF1, CXCR4, and VEGF are key players. We investigated these angiogenesis-related markers and their prognostic value in patients with PM arising from CRC treated with CRS and HIPEC. PATIENTS AND METHODS: Clinicopathological data and tissue specimens were collected in 2 tertiary referral centers from 52 patients who underwent treatment for isolated PM of CRC. Whole tissue specimens were subsequently analyzed for protein expression of HIF1a, SDF1, CXCR4, and VEGF by immunohistochemistry. Microvessel density (MVD) was analyzed by CD31 immunohistochemistry. The relationship between overall survival (OS) and protein expression as well as other clinicopathological characteristics was analyzed. RESULTS: Univariate analysis showed that high peritoneal cancer index (PCI), resection with residual disease and high expression of VEGF were negatively correlated with OS after treatment with CRS and HIPEC (P < 0.01, P < 0.01, and P = 0.02, respectively). However, no association was found between the other markers and OS (P > 0.05). Multivariate analysis showed an independent association between OS and PCI, resection outcome and VEGF expression (multivariate HR: 6.1, 7.8 and 3.8, respectively, P ≤ 0.05). CONCLUSIONS: An independent association was found between high VEGF expression levels and worse OS after CRS and HIPEC. The addition of VEGF expression to the routine clinicopathological workup could help to identify patients at risk for early treatment failure. Furthermore, VEGF may be a potential target for adjuvant treatment in these patients.
Assuntos
Moduladores da Angiogênese/metabolismo , Biomarcadores Tumorais/metabolismo , Quimioterapia do Câncer por Perfusão Regional , Neoplasias Colorretais/patologia , Procedimentos Cirúrgicos de Citorredução , Hipertermia Induzida , Neoplasias Peritoneais/secundário , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Adenocarcinoma/terapia , Adenocarcinoma Mucinoso/metabolismo , Adenocarcinoma Mucinoso/patologia , Adenocarcinoma Mucinoso/terapia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Células em Anel de Sinete/metabolismo , Carcinoma de Células em Anel de Sinete/patologia , Carcinoma de Células em Anel de Sinete/terapia , Quimioterapia Adjuvante , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/terapia , Terapia Combinada , Feminino , Seguimentos , Humanos , Técnicas Imunoenzimáticas , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Estadiamento de Neoplasias , Neovascularização Patológica/prevenção & controle , Neoplasias Peritoneais/metabolismo , Neoplasias Peritoneais/terapia , Prognóstico , Estudos Prospectivos , Taxa de SobrevidaRESUMO
BACKGROUND: Resection of colorectal cancer liver metastasis (CRCLM) with curative intent has long-term benefit in ~40% of cases. Prognostic biomarkers are needed to improve clinical management and reduce futile surgeries. Expression of epidermal growth factor receptor (EGFR) and prostaglandin-endoperoxide synthase 2 (PTGS2; also known as cyclooxygenase-2) has been associated with carcinogenesis and survival. We investigated the prognostic value of EGFR and PTGS2 expression in patients with resected CRCLM. METHODS: Formalin-fixed paraffin-embedded CRCLM tissue and corresponding primary tumour specimens from a multi-institutional cohort of patients who underwent liver resection between 1990 and 2010 were incorporated into tissue microarrays (TMAs). TMAs were stained for EGFR and PTGS2 by immunohistochemistry. The hazard rate ratio (HRR) for the association between expression in CRCLM and overall survival was calculated using a 500-fold cross-validation procedure. RESULTS: EGFR and PTGS2 expression could be evaluated in 323 and 351 patients, respectively. EGFR expression in CRCLM was associated with poor prognosis (HRR 1.54; P<0.01) with a cross-validated HRR of 1.47 (P=0.03). PTGS2 expression was also associated with poor prognosis (HRR 1.60; P<0.01) with a cross-validated HRR of 1.63 (P<0.01). Expression of EGFR and PTGS2 remained prognostic after multivariate analysis with standard clinicopathological variables (cross-validated HRR 1.51; P=0.02 and cross-validated HRR 1.59; P=0.01, respectively). Stratification for the commonly applied systemic therapy regimens demonstrated prognostic value for EGFR and PTGS2 only in the subgroup of patients who were not treated with systemic therapy (HRR 1.78; P<0.01 and HRR 1.64; P=0.04, respectively), with worst prognosis when both EGFR and PTGS2 were highly expressed (HRR 3.08; P<0.01). Expression of PTGS2 in CRCLM was correlated to expression in patient-matched primary tumours (P=0.02, 69.2% concordance). CONCLUSIONS: EGFR and PTGS2 expressions are prognostic molecular biomarkers with added value to standard clinicopathological variables for patients with resectable CRCLM.
Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias Colorretais/metabolismo , Ciclo-Oxigenase 2/metabolismo , Receptores ErbB/metabolismo , Neoplasias Hepáticas/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Neoplasias Colorretais/cirurgia , Feminino , Humanos , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/cirurgia , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
BACKGROUND: Five-year survival after resection of colorectal cancer liver metastasis (CRLCM) is <30%. We recently found that aurora kinase A (AURKA) drives 20q gain-associated tumour progression and is associated with disease recurrence. This study evaluates the prognostic value of AURKA expression in CRCLM of patients who underwent liver resection. METHODS: Tissue microarrays (TMAs) were generated using formalin-fixed paraffin-embedded CRCLM and matched primary tumour from a multi-institutional cohort of patients with CRCLM who underwent liver resection between 1990 and 2010. Tissue microarrays were stained for AURKA using immunohistochemistry, and a hazard rate ratio (HRR) for the association between overall survival (OS) and nuclear AURKA expression in CRCLM was calculated. Results were validated by 500-fold cross-validation. RESULTS: The expression of AURKA was evaluated in CRCLM of 343 patients. High AURKA expression was associated with poor OS (HRR 1.55, P<0.01), with a cross-validated average HRR of 1.57 (P=0.02). Average HRR was adjusted for the established prognostic clinicopathological variables in a multivariate analysis (average HRR 1.66; P=0.02). The expression of AURKA in CRCLM was correlated to its expression in corresponding primary tumour (P<0.01). CONCLUSION: The expression of AURKA protein is a molecular biomarker with prognostic value for patients with CRCLM, independent of established clinicopathological variables.
Assuntos
Aurora Quinase A/biossíntese , Neoplasias Colorretais/enzimologia , Neoplasias Colorretais/patologia , Neoplasias Hepáticas/enzimologia , Neoplasias Hepáticas/secundário , Adulto , Idoso , Idoso de 80 Anos ou mais , Aurora Quinase A/genética , Biomarcadores Tumorais/biossíntese , Biomarcadores Tumorais/genética , Neoplasias Colorretais/genética , Feminino , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/enzimologia , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/patologia , Prognóstico , Adulto JovemRESUMO
AIM: This study was designed to assess the relationship between diverticulitis and the development of colorectal cancer (CRC) and colonic adenomas. METHOD: A retrospective study was longitudinally conducted. Patients who had been admitted to the hospital between 1990 and 2000 with diverticulitis were retrieved and the incidence of CRC and prevalence of colonic adenomas in these patients was determined. Data were collected from the electronic clinical and pathology records. The incidence of CRC and prevalence of adenomas in this patient cohort was compared with the general population. The patients were followed until 2008. RESULTS: A total of 288 patients with diverticulitis were included (167 of whom were female patients [58%]). The mean age of patients at admittance for diverticulitis was 66 years (range: 27-92). CRC was detected in five patients (1.7%) (95% CI 0.8-3.5) with a mean age of 77 years; colonic adenomas were found in 18 patients (6.3%) (95% CI 4.3-9.0) with a mean age of 62 years. The lifetime risks of developing CRC and adenomas were presumed to be 4% and 20% respectively. Expected rates for CRC and adenomas in our patients were calculated as 17 (95% CI 4.0-8.6) and 69 patients (95% CI 20.1-28.3) respectively. CONCLUSION: This study showed a lower prevalence of CRC and colonic adenomas in patients with diverticulitis compared with the lifetime risk which means that diverticulitis is not a risk factor for development of CRC and adenomas. Long-term colonic screening after a negative colonoscopy for diverticulitis (generally performed several weeks after recovery) does not seem to be justified.
Assuntos
Adenoma/complicações , Neoplasias Colorretais/complicações , Doença Diverticular do Colo/complicações , Adenoma/diagnóstico , Adenoma/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/epidemiologia , Intervalos de Confiança , Doença Diverticular do Colo/tratamento farmacológico , Doença Diverticular do Colo/cirurgia , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , RiscoRESUMO
BACKGROUND: DNA aneuploidy reflects gross genomic changes. It can be measured by flow cytometry (FCM-DNA) or image cytometry (ICM-DNA). In gastric cancer, the prevalence of DNA aneuploidy has been reported to range from 27 to 100%, with conflicting associations with clinicopathological variables. The aim of our study was to compare the DNA ploidy status measured using FCM-DNA and ICM-DNA in gastric cancer and to evaluate its association with clinicopathological variables. METHODS: Cell nuclei were isolated from 221 formalin-fixed, paraffin-embedded gastric cancer samples. DNA ploidy was assessed using FCM-DNA and ICM-DNA. RESULTS: A total of 178 (80.5%) gastric cancer samples were classified as DNA aneuploid using FCM-DNA, compared with 172 (77.8%) gastric cancer samples when using ICM-DNA. Results obtained from both methods were concordant in 183 (82.8%) cases (kappa=0.48). Patients with ICM-DNA diploid gastric cancer survived significantly longer than those with ICM-DNA aneuploid gastric cancer (log rank 10.1, P=0.001). For FCM-DNA data, this difference did not reach statistical significance. The multivariate Cox model showed that ICM-DNA ploidy status predicted patient survival independently of tumour-node-metastasis status. CONCLUSION: ICM-DNA ploidy status is an independent predictor of survival in gastric cancer patients and may therefore be a more clinically relevant read out of gross genomic damage than FCM-DNA.
Assuntos
Aneuploidia , DNA de Neoplasias/análise , Citometria por Imagem/métodos , Neoplasias Gástricas/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ploidias , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/patologiaRESUMO
The purpose of this study is to evaluate the prognostic value of the combined assessment of multiple molecular markers related to the epidermal growth factor receptor (EGFR) pathway in resected non-small cell lung cancer (NSCLC) patients. Tumour specimens of 178 NSCLC patients were collected and analysed for EGFR and KRAS mutation status by DNA sequencing, and for EGFR copy number by fluorescent in situ hybridisation. Tissue microarrays were generated and used to determine the expression of multiple EGFR pathway-related proteins by immunohistochemistry. We analysed the association between each marker and patient prognosis. Univariate analyses for each clinical variable and each molecular marker were performed using Kaplan-Meier curves and log-rank tests. From these results, we selected the variables KRAS mutations and expression of cytoplasmic EGFR, granular pERK, nuclear pSTAT3, cytoplasmic E-cadherin and cytoplasmic pCMET to enter into a Cox proportional hazards model, along with stage as the strongest clinical variable related with prognosis. Of the EGFR-related markers evaluated here, the markers EGFR, pERK, pSTAT3, E-cadherin, pCMET and mutations in KRAS were associated with survival when analysed in combination in our patient cohort, with P=0.00015 as the P-value for a test of the additional impact of markers on prognosis, after taking stage into consideration. Confirmation of the impact of these markers in independent studies will be necessary.
Assuntos
Carcinoma Pulmonar de Células não Pequenas/mortalidade , Receptores ErbB/fisiologia , Neoplasias Pulmonares/mortalidade , Transdução de Sinais/fisiologia , Caderinas/análise , Carcinoma Pulmonar de Células não Pequenas/genética , Receptores ErbB/análise , Receptores ErbB/genética , Feminino , Dosagem de Genes , Genes ras , Humanos , Neoplasias Pulmonares/genética , Masculino , Análise Multivariada , Mutação , Prognóstico , Fator de Transcrição STAT3/análiseRESUMO
The entorhinal cortex (EC) projects via the perforant pathway to all subfields in the hippocampal formation. One can distinguish medial and lateral components in the pathway, originating in corresponding medial and lateral subdivisions of EC. We analyzed the innervation by medial and lateral perforant pathway fibers of parvalbumin-expressing neurons in the subiculum. A neuroanatomical tracer (biotinylated dextran amine, BDA) was stereotaxically injected in the medial or lateral entorhinal cortex, thus selectively labeling either perforant pathway component. Transport was allowed for 1 week. Transported BDA was detected with streptavidin-Alexa Fluor 488. Parvalbumin neurons were visualized via immunofluorescence histochemistry, using the fluorochrome Alexa Fluor 594. Via a random systematic sampling scheme using a two-channel, sequential-mode confocal laser scanning procedure, we obtained image series at high magnification from the molecular layer of the subiculum. Labeled entorhinal fibers and parvalbumin-expressing structures were three dimensionally (3D) reconstructed using computer software. Further computer analysis revealed that approximately 16% of the 3D objects ('boutons') of BDA-labeled fibers was engaged in contacts with parvalbumin-immunostained dendrites in the subiculum. Both medial and lateral perforant pathway fibers and their boutons formed such appositions. Contacts are suggestive for synapses. We found no significant differences between the medial and lateral components in the relative numbers of contacts. Thus, the medial and lateral subdivisions of the entorhinal cortex similarly tune the firing of principal neurons in the subiculum by way of parvalbumin positive interneurons in their respective terminal zones.
Assuntos
Córtex Entorrinal/fisiologia , Hipocampo/citologia , Neurônios/metabolismo , Parvalbuminas/metabolismo , Via Perfurante/fisiologia , Animais , Biotina/análogos & derivados , Biotina/metabolismo , Dextranos/metabolismo , Feminino , Hipocampo/metabolismo , Imageamento Tridimensional , Microscopia Confocal , Microscopia Eletrônica de Transmissão/métodos , Fibras Nervosas/fisiologia , Fibras Nervosas/ultraestrutura , Neurônios/ultraestrutura , Via Perfurante/ultraestrutura , Terminações Pré-Sinápticas/metabolismo , Terminações Pré-Sinápticas/ultraestrutura , Ratos , Ratos WistarRESUMO
Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) can increase survival of colorectal cancer (CRC) patients with peritoneal metastases (PM). This treatment is associated with high morbidity and mortality rates. Therefore, improvement of patient selection is necessary. Assuming that the clinical phenotype is dictated by biological mechanisms, biomarkers could play a crucial role in this process. Since it is unknown whether and to what extent angiogenesis influences the course of disease in patients with PM, we investigated the expression of two angiogenesis-related markers and their relation to overall survival (OS) in CRC patients after CRS and HIPEC. Clinicopathological data and tissue samples were collected from 65 CRC patients with isolated metastases to the peritoneum that underwent CRS and HIPEC. Whole tissue specimens from PM were evaluated for versican (VCAN) expression, VEGF expression and microvessel density (MVD) by immunohistochemistry. The relation between these markers and OS was assessed using univariate and multivariate analysis. Associations between VEGF expression, VCAN expression, MVD and clinicopathological data were tested. High stromal VCAN expression was associated with high MVD (p = 0.001), better resection outcome (p = 0.003) and high T-stage (p = 0.027). High epithelial VCAN expression was associated with MVD (p = 0.007) and a more complete resection (p < 0.001). In multivariate analysis, simplified peritoneal cancer index (p = 0.001), VEGF expression levels (p = 0.012), age (p = 0.030), epithelial VCAN expression levels (p = 0.042) and lymph node status (p = 0.053) were associated with OS. Concluding, VCAN and VEGF were associated with survival in CRC patients with PM after CRS and HIPEC. Independent validation in a well-defined patient cohort is required to confirm the putative prognostic role of these candidate biomarkers.
Assuntos
Biomarcadores Tumorais/biossíntese , Neoplasias Colorretais/genética , Neoplasias Peritoneais/genética , Fator A de Crescimento do Endotélio Vascular/biossíntese , Versicanas/biossíntese , Adulto , Idoso , Biomarcadores Tumorais/genética , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/cirurgia , Procedimentos Cirúrgicos de Citorredução , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Hipertermia Induzida , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Neovascularização Patológica/genética , Neovascularização Patológica/patologia , Neoplasias Peritoneais/tratamento farmacológico , Neoplasias Peritoneais/secundário , Neoplasias Peritoneais/cirurgia , Fator A de Crescimento do Endotélio Vascular/genética , Versicanas/genéticaRESUMO
The estimated prevalence of oral leukoplakia is worldwide approximately 2%, with an annual malignant transformation rate of approximately 1%. The aim of the present study was to evaluate the possible contribution of ploidy measurement to the prediction of the clinical course, in a well defined cohort of patients with oral leukoplakia. Ploidy was measured by both flow cytometry (FCM-DNA) and image cytometry (ICM-DNA) and we focussed on the comparison of the two different techniques to determine ploidy. A total of 41 patients have been included, with a mean age of 59 years (range 36-78 years). With FCM-DNA, three lesions were aneuploid, with ICM-DNA, 19 lesions were aneuploid. DNA ploidy was compared with clinicopathological and patients parameters. There were no statistically significant differences between DNA ploidy and any patient factor with both FCM-DNA and ICM-DNA. Using FCM-DNA, DNA aneuploid lesions showed statistically significant more dysplasia (p=0.04) than diploid lesions. Furthermore, DNA aneuploid lesions were more frequently encountered at high-risk locations (p=0.03) as being determined with FCM-DNA. These relations were not found when DNA ploidy was determined with ICM-DNA.
Assuntos
Aneuploidia , DNA de Neoplasias/genética , Citometria de Fluxo/métodos , Citometria por Imagem/métodos , Leucoplasia Oral/genética , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos RetrospectivosRESUMO
AIM OF THE STUDY: Loss of the nuclear lamina protein lamin A/C (LMNA) has been observed in several human malignancies. The present study aimed to investigate associations between LMNA expression and clinical outcome in colon cancer patients. PATIENTS AND METHODS: Clinicopathological data and formalin-fixed paraffin embedded tissues were collected from 370 stage II and III colon cancer patients. Tissue microarrays were constructed, stained for lamin A/C and evaluated microscopically. Microsatellite instability status was determined for 318 tumours. RESULTS: Low levels of LMNA expression were observed in 17.8% of colon tumours, with disease recurrence occurring in 45.5% of stage II and III colon cancer patients with LMNA-low expressing tumours compared to 29.6% of patients with LMNA-high expressing tumours (p=0.01). For stage II patients, disease recurrence was observed for 35.7% of LMNA-low compared to 20.3% of LMNA-high expressing tumours (p=0.03). Microsatellite stable (MSS) tumours exhibited more frequently low LMNA expression than microsatellite instable (MSI) tumours (21% versus 9.8%; p=0.05). Interestingly, disease recurrence among LMNA-low and LMNA-high expressing MSS tumours varied significantly for stage III patients who had not received adjuvant chemotherapy (100% versus 37.8%; p<0.01) while no such difference was observed for patients who received adjuvant chemotherapy (46.7% versus 46.0%; p=0.96). CONCLUSION: These data indicate that low expression of LMNA is associated with an increased disease recurrence in stage II and III colon cancer patients, and suggest that these patients in particular may benefit from adjuvant chemotherapy.
Assuntos
Biomarcadores Tumorais/análise , Neoplasias do Colo/química , Neoplasias do Colo/patologia , Lamina Tipo A/análise , Adulto , Idoso , Neoplasias do Colo/cirurgia , Intervalo Livre de Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Masculino , Instabilidade de Microssatélites , Pessoa de Meia-Idade , Análise Multivariada , Recidiva Local de Neoplasia/química , Recidiva Local de Neoplasia/diagnóstico , Estadiamento de Neoplasias , Países Baixos , Razão de Chances , Valor Preditivo dos Testes , Prognóstico , Análise Serial de Proteínas , Recidiva , Fatores de RiscoAssuntos
Biomarcadores Tumorais/análise , Neoplasias/irrigação sanguínea , Neovascularização Patológica/diagnóstico , Antígenos CD/análise , Fatores de Crescimento Endotelial/análise , Histocitoquímica/métodos , Humanos , Metástase Linfática , Linfocinas/análise , Neoplasias/patologia , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio VascularRESUMO
The hypoxia-inducible factor 1 (HIF-1) plays a critical role in cellular responses to hypoxia. The aim of the present study was to evaluate which genes are induced by hypoxia, and whether this induction is mediated by HIF-1, by expression microarray analysis of wt and HIF-1alpha null mouse fibroblasts. Forty-five genes were up-regulated by hypoxia and 40 (89%) of these were regulated by HIF-1. Of the 114 genes down-regulated by hypoxia, 19 (17%) were HIF-1-dependent. All glycolytic enzymes were strongly up-regulated by hypoxia in a HIF-1-dependent manner. Genes already known to be related to hypoxia, such as glucose transporter 1, BNIP3, and hypoxia-induced gene 1, were induced. In addition, multiple new HIF-1-regulated genes were identified, including genes involved in metabolism (adenylate kinase 4, galactokinase), apoptosis (galectin-3 and gelsolin), and invasion (RhoA). Genes down-regulated by hypoxia were involved in cytoskeleton maintenance (Rho kinase), mRNA processing (heterogeneous nuclear ribonucleoprotein H1 and splicing factor), and DNA repair (REV3). Furthermore, seven cDNAs from genes with unknown function or expressed sequence tags (ESTs) were up-regulated and 27 such cDNAs were down-regulated. In conclusion, hypoxia causes down- rather than up-regulation of gene expression and HIF-1 seems to play a major role in the regulation of hypoxia-induced genes.