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BACKGROUND AND AIMS: Initial reports on US COVID-19 showed different outcomes in different races. In this study we use a diverse large cohort of hospitalized COVID-19 patients to determine predictors of mortality. METHODS: We analyzed data from hospitalized COVID-19 patients (n = 5852) between March 2020- August 2020 from 8 hospitals across the US. Demographics, comorbidities, symptoms and laboratory data were collected. RESULTS: The cohort contained 3,662 (61.7%) African Americans (AA), 286 (5%) American Latinx (LAT), 1,407 (23.9%), European Americans (EA), and 93 (1.5%) American Asians (AS). Survivors and non-survivors mean ages in years were 58 and 68 for AA, 58 and 77 for EA, 44 and 61 for LAT, and 51 and 63 for AS. Mortality rates for AA, LAT, EA and AS were 14.8, 7.3, 16.3 and 2.2%. Mortality increased among patients with the following characteristics: age, male gender, New York region, cardiac disease, COPD, diabetes mellitus, hypertension, history of cancer, immunosuppression, elevated lymphocytes, CRP, ferritin, D-Dimer, creatinine, troponin, and procalcitonin. Use of mechanical ventilation (p = 0.001), shortness of breath (SOB) (p < 0.01), fatigue (p = 0.04), diarrhea (p = 0.02), and increased AST (p < 0.01), significantly correlated with death in multivariate analysis. Male sex and EA and AA race/ethnicity had higher frequency of death. Diarrhea was among the most common GI symptom amongst AAs (6.8%). When adjusting for comorbidities, significant variables among the demographics of study population were age (over 45 years old), male sex, EA, and patients hospitalized in New York. When adjusting for disease severity, significant variables were age over 65 years old, male sex, EA as well as having SOB, elevated CRP and D-dimer. Glucocorticoid usage was associated with an increased risk of COVID-19 death in our cohort. CONCLUSION: Among this large cohort of hospitalized COVID-19 patients enriched for African Americans, our study findings may reflect the extent of systemic organ involvement by SARS-CoV-2 and subsequent progression to multi-system organ failure. High mortality in AA in comparison with LAT is likely related to high frequency of comorbidities and older age among AA. Glucocorticoids should be used carefully considering the poor outcomes associated with it. Special focus in treating patients with elevated liver enzymes and other inflammatory biomarkers such as CRP, troponin, ferritin, procalcitonin, and D-dimer are required to prevent poor outcomes.
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COVID-19 , Negro ou Afro-Americano , Idoso , Biomarcadores , Diarreia , Ferritinas , Hospitalização , Humanos , Masculino , Pessoa de Meia-Idade , Pró-Calcitonina , Estudos Retrospectivos , SARS-CoV-2 , TroponinaRESUMO
Pathologic alterations in epigenetic regulation have long been considered a hallmark of many cancers, including hepatocellular carcinoma (HCC). In a healthy individual, the relationship between DNA methylation and microRNA (miRNA) expression maintains a fine balance; however, disruptions in this harmony can aid in the genesis of cancer or the propagation of existing cancers. The balance between DNA methylation and microRNA expression and its potential disturbance in HCC can vary by race. There is emerging evidence linking epigenetic events including DNA methylation and miRNA expression to cancer disparities. In this paper, we evaluate the epigenetic mechanisms of racial heterogenity in HCC through an integrated analysis of DNA methylation, miRNA, and combined regulation of gene expression. Specifically, we generated DNA methylation, mRNA-seq, and miRNA-seq data through the analysis of tumor and adjacent non-tumor liver tissues from African Americans (AA) and European Americans (EA) with HCC. Using mixed ANOVA, we identified cytosine-phosphate-guanine (CpG) sites, mRNAs, and miRNAs that are significantly altered in HCC vs. adjacent non-tumor tissue in a race-specific manner. We observed that the methylome was drastically changed in EA with a significantly larger number of differentially methylated and differentially expressed genes than in AA. On the other hand, the miRNA expression was altered to a larger extent in AA than in EA. Pathway analysis functionally linked epigenetic regulation in EA to processes involved in immune cell maturation, inflammation, and vascular remodeling. In contrast, cellular proliferation, metabolism, and growth pathways are found to predominate in AA as a result of this epigenetic analysis. Furthermore, through integrative analysis, we identified significantly differentially expressed genes in HCC with disparate epigenetic regulation, associated with changes in miRNA expression for AA and DNA methylation for EA.
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The African American (AA) community in Washington DC is at an elevated risk for hepatocellular carcinoma (HCC) that has a dismal prognosis. The recent rapid increase in the incidence and diagnosis of HCC and liver metastases (LM) in DC prompted us to evaluate the past six decades of this incidence and some of its underlying causes using a single institutional cohort in a hospital located in the center of the city. Electronic medical and pathology records of 454 liver cancer patients from 1959 to 2013 at Howard University Hospital (HUH) were reviewed. Demographic, clinical and pathology characteristics were examined, and statistical analysis was performed using Wilcoxon rank-sum test. Incidence of HCC rose substantially between 1959 and 2013, increasing eight-fold from 1.05 to 8.0 per 100,000 AAs. The rate of increase in the last decade was highest at 550%. Cases were disproportionately male (67.2%), and median age at diagnosis was 57 years. Towards the last decade, the most common etiology for HCC was nonalcoholic fatty liver disease (NAFLD) followed by NAFLD/HCV combination. Liver cancer was clustered in the eastern region of DC in wards 4, 5, 7, and 8. Cases of liver metastases clinically diagnosed and confirmed by biopsies increased 96.4% from 1959 to 1968 to 2009-2013. This study confirms that HCC incidence has been increasing (initially driven by HCV, and NAFLD in the latter decades) more rapidly in DC than previously believed, highlighting the impact of case definitions especially regarding NAFLD in the context of changing diagnostic approaches including the revised ICD10. The rising burden, disproportionate population distribution, and low survival rate among AAs emphasize the importance of prevention and early detection as a public health imperative.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Carcinoma Hepatocelular/epidemiologia , Estudos de Coortes , Humanos , Incidência , Neoplasias Hepáticas/epidemiologia , Masculino , Fatores de RiscoRESUMO
Weight reduction continues to be first-line therapy in the treatment of hypertension (HTN). However, the long-term effect of bariatric malabsorptive surgical techniques such as Roux-en-Y Gastric Bypass (RYGB) surgery in the management of hypertension (HTN) is less clear. African Americans (AA) are disproportionately affected by obesity and hypertension and have inconsistent outcomes after bariatric surgery (BS). Despite a plethora of bariatric literature, data about characteristics of a predominantly AA bariatric hypertensive cohort including hypertension in obese (HIO) are scarce and underreported. The aims of this study were, (1) to describe the preoperative clinical characteristics of HIO with respect to HTN status and age, and (2) to identify predictors of HTN resolution one year after RYGB surgery in an AA bariatric cohort enrolled at the Howard University Center for Wellness and Weight Loss Surgery (HUCWWS). In the review of 169 AA bariatric patients, the average BMI was 48.50 kg/m2 and the average age was 43.86 years. Obese hypertensive patients were older (46 years vs. 37.89 years; p < .0001); had higher prevalence of diabetes mellitus (DM, 43.09% vs. 10.87%; p < .0001) and dyslipidemia (38.2% vs. 13.04%; p 0.002). Hypertensive AA who were taking ≥ 2 antihypertensive medications prior to RYGB were 18 times less likely to experience HTN resolution compared to hypertensive AA taking 0-1 medications, who showed full or partial response. Also, HIO was less likely to resolve after RYGB surgery in patients who needed ≥ 2 antihypertensive medications prior to surgical intervention.
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Anti-Hipertensivos/uso terapêutico , Cirurgia Bariátrica/métodos , População Negra/estatística & dados numéricos , Derivação Gástrica/métodos , Hipertensão/terapia , Obesidade/cirurgia , Redução de Peso , Adulto , Feminino , Humanos , Hipertensão/etnologia , Hipertensão/etiologia , Hipertensão/patologia , Masculino , Obesidade/complicações , Obesidade/etnologia , Estudos Retrospectivos , Resultado do TratamentoRESUMO
BACKGROUND: African Americans (AA) are at high risk for Colorectal Cancer (CRC). Studies report a 30-60% increase in CRC risk with physical inactivity, obesity and metabolic syndrome. Activation of the WNT/ß-catenin (CTNNB1) signaling pathway plays a critical role in colorectal carcinogenesis. Accumulating evidence also indicates a role of WNT-CTNNB1 signaling in obesity and metabolic diseases. AIM: To examine the association between obesity, ß-Catenin expression and colonic lesions in African Americans. METHODS: We reviewed the pathology records of 152 colorectal specimens from 2010 to 2012 (46 CRCs, 74 advanced adenomas and 32 normal colon tissues). Tissue Microarrays (TMA) were constructed from these samples. Immunohistochemistry (IHC) for CTNNB1 (ß-Catenin; clone ß-Catenin-1) was performed on the constructed TMAs. The IHC results were evaluated by 2 pathologists and the nuclear intensity staining was scored from 0 to 4. BMI, sex, age, location of the lesion and other demographic data were obtained. RESULTS: Positive nuclear staining in normal, advanced adenoma and CRC was 0, 24 and 41%, respectively (P < 0.001). CRC was asso ciated with positive status for nuclear CTNNB1 intensity (adjusted OR: 3.40, 95%CI = 1.42-8.15, P = 0.006 for positive nuclear staining) compared to non-CRC samples (Normal or advanced adenoma). Nuclear staining percentage has a fair diagnostic ability for CRC with an AUC of 0.63 (95%CI = 0.55-0.71). Overweight/obese patients (BMI > 25) did not show a significant difference in (p = 0.3) nuclear CTNNB1 staining (17% positive in normal weight vs. 27% positive in overweight/obese). The association between nuclear intensity and CRC was not different between normal and overweight patients (P for interaction = 0.6). The positive nuclear CTNNB1status in CRC stage III and IV (35% of all CRC) was not different from stage I and II (50% vs. 36%, respectively, P = 0.4). CONCLUSION: In our study, advanced adenoma and CRC were associated with activation of ß-catenin in physically fit, overweight and obese patients. Thus, obesity and WNT/ß-Catenin pathway seem to be independent in African American patients. WNT/ß-Catenin signaling pathway has a potential to be used as an effector in colon carcinogenic transformation. Whether or not BMI is a modifier of this pathway needs to be investigated further.
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Neoplasias Colorretais , beta Catenina , Negro ou Afro-Americano , Humanos , Obesidade/complicações , Via de Sinalização Wnt , beta Catenina/genética , beta Catenina/metabolismoRESUMO
BACKGROUND: Colitis is generally considered a risk factor for colon neoplasia. However, not all types of colitis seem to have equal neoplastic transformation potential. AIM: To determine the prevalence of colorectal polyps in a predominantly African American population with inflammatory bowel disease (IBD) and Non-IBD/Non-Infectious Colitis (NIC). METHODS: We retrospectively evaluated medical records of 1060 patients previously identified with colitis at Howard University Hospital, based on ICD-10 code. Among these, 485 patients were included in the study: 70 IBD and 415 NIC based on a thorough review of colonoscopy, pathology and clinical reports. Logistic regression analysis was applied to estimate the risk of polyps in patients with IBD compared to those with NIC after adjusting for age and sex. A subgroup analysis within the IBD group was performed. RESULTS: Of the 485 patients, 415 were NIC and 70 were IBD. Seventy-three percent of the NIC patients and 81% of the IBD patients were African Americans. Forty six percent of IBD and 41% of NIC cases were male. IBD patients were younger than NIC patients (median age of 38 years vs. 50, P < 0.001). The prevalence of all types of polyps was 15.7 and 8.2% in the IBD and NIC groups, respectively (P = 0.045). Among patients with polyps, the prevalence of inflammatory polyps was higher in the IBD group (55%) compared to the NIC group (12%). After adjusting for age, sex and race, odds ratio of inflammatory polyps in IBD patients was 6.0 (P = 0.016). Adenoma prevalence was 4.3% (3/70) in IBD patients and 3.9% (16/415) in the NIC patients (p = 0.75). The anatomic distribution of lesions and colitis shows that polyps occur predominantly in the colitis field regardless of colitis type. More polyps were present in the ulcerative colitis patients when compared to Crohn's disease patients (27% vs. 5%, P < 0.001) within the IBD group. CONCLUSION: Our study shows that inflammatory polyps are more common in IBD patients when compared to NIC patients. Most polyps were in the same location as the colitis.
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Colite Ulcerativa/complicações , Colite/complicações , Pólipos do Colo/epidemiologia , Doença de Crohn/complicações , Doenças Inflamatórias Intestinais/complicações , Adulto , Negro ou Afro-Americano/estatística & dados numéricos , Colite/etnologia , Colite Ulcerativa/etnologia , Pólipos do Colo/etnologia , Pólipos do Colo/etiologia , Colonoscopia/estatística & dados numéricos , Doença de Crohn/etnologia , Feminino , Humanos , Doenças Inflamatórias Intestinais/etnologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Prevalência , Estudos Retrospectivos , Medição de Risco , Fatores de RiscoRESUMO
BACKGROUND: The established role miRNA-mRNA regulation of gene expression has in oncogenesis highlights the importance of integrating miRNA with downstream mRNA targets. These findings call for investigations aimed at identifying disease-associated miRNA-mRNA pairs. Hierarchical integrative models (HIM) offer the opportunity to uncover the relationships between disease and the levels of different molecules measured in multiple omic studies. METHODS: The HIM model we formulated for analysis of mRNA-seq and miRNA-seq data can be specified with two levels: (1) a mechanistic submodel relating mRNAs to miRNAs, and (2) a clinical submodel relating disease status to mRNA and miRNA, while accounting for the mechanistic relationships in the first level. RESULTS: mRNA-seq and miRNA-seq data were acquired by analysis of tumor and normal liver tissues from 30 patients with hepatocellular carcinoma (HCC). We analyzed the data using HIM and identified 157 significant miRNA-mRNA pairs in HCC. The majority of these molecules have already been independently identified as being either diagnostic, prognostic, or therapeutic biomarker candidates for HCC. These pairs appear to be involved in processes contributing to the pathogenesis of HCC involving inflammation, regulation of cell cycle, apoptosis, and metabolism. For further evaluation of our method, we analyzed miRNA-seq and mRNA-seq data from TCGA network. While some of the miRNA-mRNA pairs we identified by analyzing both our and TCGA data are previously reported in the literature and overlap in regulation and function, new pairs have been identified that may contribute to the discovery of novel targets. CONCLUSION: The results strongly support the hypothesis that miRNAs are important regulators of mRNAs in HCC. Furthermore, these results emphasize the biological relevance of studying miRNA-mRNA pairs.
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Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/genética , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , MicroRNAs/genética , RNA Mensageiro/genética , Adulto , Carcinoma Hepatocelular/patologia , Feminino , Perfilação da Expressão Gênica , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , PrognósticoRESUMO
BACKGROUND: Colorectal and endometrial lesions increase with age. It is not known if these two precursor lesions in sporadic cases associate with each other. AIM: To determine the association between colorectal polyps and endometrial polyps (EP) in African Americans. METHODS: We reviewed records of patients referred to gynecology clinics and had colonoscopy at Howard University Hospital from January 2004 to December 2015. We defined cases as all patients who had EP and underwent colonoscopy. For controls, we used EP-free patients who underwent colonoscopy. Logistic regression analysis was used to assess the association between colon polyps and EP. RESULTS: The median age was 60 years in 118 Cases and 57 years in 664 Controls. The overall colorectal polyps prevalence in the two groups was not statistically different (54% in controls vs. 52% in cases, P = 0.60). Sessile serrated adenoma/polyps (SSPs) were more frequent in cases (8% vs. 2% in controls, P = 0.003). Sigmoid and rectal locations were more prevalent in controls than cases. In multivariate analysis and after adjusting for age, diabetes mellitus (DM), and BMI, SSPs were associated with EP occurrence with an odds ratio of 4.6 (CI 1.2-16.7, P = 0.022). CONCLUSION: Colorectal polyp prevalence was similar in EP patients compared to EP-free controls. However, we observed a significant association between higher-risk SSPs in patients with EP. The prevalence of smoking and DM was higher in these patients. Females with EP might benefit from a screening for colonic lesions in an age-independent manner.
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Negro ou Afro-Americano , Pólipos do Colo/etnologia , Neoplasias Colorretais/etnologia , Pólipos/etnologia , Doenças Uterinas/etnologia , Idoso , Pólipos do Colo/diagnóstico , Neoplasias Colorretais/diagnóstico , Diabetes Mellitus/etnologia , Feminino , Humanos , Pessoa de Meia-Idade , Pólipos/diagnóstico , Prevalência , Fatores Raciais , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fumar/efeitos adversos , Fumar/etnologia , Doenças Uterinas/diagnósticoRESUMO
The complexity of TP73 expression and its functionality, as well as the role of TP73 in tumorigenesis, unlike its cousin TP53, which is an established tumor suppressor, have remained elusive to date. In this study, we isolated two stem cell lines (HepCY & HepCO) from normal young and old human liver tissues. We determined TP73 expression in HepCY and HepCO, hepatocellular cancer (HCC) cell lines (HepG2, SNU398, SNU449 and SNU475), gastrointestinal cancer (GI) cell lines (Caco2 and HCT116) and normal skin fibroblasts cell line (HS27). Immunohistochemical analyses of TP73 expression was also performed in non-cancerous and adjacent cancerous liver tissues of HCC patients. The results show that TP73 expression is exclusive to the cancer cell lines and not the adjacent normal liver tissues. Moreover, methylation-specific PCR and bisulfite sequencing studies revealed that TP73 promoter is activated only in cancer cell lines by DNA methylation. Furthermore, ChIP assay results demonstrated that a chromosomal networking protein (CTCF) and tumor protein p53 (TP53) bind to TP73 promoter and regulate TP73 expression. Our observations demonstrate that a positive correlation in tumorigenesis exists between TP73 expression and DNA methylation in promoter regions of TP73. These findings may prove significant for the development of future diagnostic and therapeutic applications.
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Carcinoma Hepatocelular/genética , Metilação de DNA/genética , Neoplasias Gastrointestinais/genética , Proteína Tumoral p73/genética , Células CACO-2 , Carcinoma Hepatocelular/patologia , Proliferação de Células/genética , Neoplasias Gastrointestinais/patologia , Regulação Neoplásica da Expressão Gênica/genética , Inativação Gênica , Células Hep G2 , Humanos , Fígado/metabolismo , Fígado/patologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Proteína Supressora de Tumor p53/genéticaRESUMO
Hepatocellular carcinoma (HCC) causes more than half a million annual deaths worldwide. Understanding the mechanisms contributing to HCC development is highly desirable for improved surveillance, diagnosis, and treatment. Liver tissue metabolomics has the potential to reflect the physiological changes behind HCC development. Also, it allows identification of biomarker candidates for future evaluation in biofluids and investigation of racial disparities in HCC. Tumor and nontumor tissues from 40 patients were analyzed by both gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-mass spectrometry (LC-MS) platforms to increase the metabolome coverage. The levels of the metabolites extracted from solid liver tissue of the HCC area and adjacent non-HCC area were compared. Among the analytes detected by GC-MS and LC-MS with significant alterations, 18 were selected based on biological relevance and confirmed metabolite identification. These metabolites belong to TCA cycle, glycolysis, purines, and lipid metabolism and have been previously reported in liver metabolomic studies where high correlation with HCC progression is implied. We demonstrated that metabolites related to HCC pathogenesis can be identified through liver tissue metabolomic analysis. Additionally, this study has enabled us to identify race-specific metabolites associated with HCC.
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Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Metaboloma/genética , Metabolômica , Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Metabolismo dos Lipídeos/genética , Fígado/metabolismo , Fígado/patologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-IdadeRESUMO
Disparities in hepatocellular carcinoma (HCC) incidence and survival have been observed between ethnic groups including African-Americans (AA) and European-Americans (EA). The evaluation of the changes in the levels of metabolites in samples stratified by race could provide a snapshot of ethnically diverse disease related pathways and identify reliable biomarkers. In this study, we considered AA and EA to investigate metabolites that may be associated with HCC in a race-specific manner. The levels of 46 metabolites in plasma samples, collected from patients recruited at MedStar Georgetown University Hospital, were analyzed by Agilent GC-qMS in selected ion monitoring (SIM) mode. A least absolute shrinkage and selection operator (LASSO) regression model was applied to select metabolites with significant changes in HCC vs. cirrhosis in three groups: (1) AA and EA combined; (2) AA separately; and (3) EA separately. In addition, metabolites that distinguish HCC cases from cirrhosis in these three groups were selected by excluding those without HCV infection. The performances of the metabolites selected by LASSO in each group were evaluated through a leave-one-out cross-validation. We identified race-specific metabolites that differentiated HCC cases from cirrhotic controls, yielding better area under the receiver operating characteristics (ROC) curve (AUC) compared to alpha-fetoprotein (AFP), the serological marker widely used for the diagnosis of HCC. This study sheds light on metabolites that could potentially be used as biomarkers for HCC by monitoring their levels in high-risk population of cirrhotic patients in a race-specific manner.
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Negro ou Afro-Americano , Carcinoma Hepatocelular , Hepacivirus , Hepatite C , Cirrose Hepática , Neoplasias Hepáticas , Modelos Biológicos , População Branca , Idoso , Carcinoma Hepatocelular/epidemiologia , Carcinoma Hepatocelular/etnologia , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Feminino , Hepatite C/epidemiologia , Hepatite C/etnologia , Hepatite C/metabolismo , Hepatite C/patologia , Humanos , Cirrose Hepática/epidemiologia , Cirrose Hepática/etnologia , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/etnologia , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-IdadeRESUMO
Increasing evidence suggests a role of the gut microbiota in colorectal carcinogenesis (CRC). To detect bacterial markers of colorectal cancer in African Americans a metabolomic analysis was performed on fecal water extracts. DNA from stool samples of adenoma and healthy subjects and from colon cancer and matched normal tissues was analyzed to determine the microbiota composition (using 16S rDNA) and genomic content (metagenomics). Metagenomic functions with discriminative power between healthy and neoplastic specimens were established. Quantitative Polymerase Chain Reaction (q-PCR) using primers and probes specific to Streptococcus sp. VT_162 were used to validate this bacterium association with neoplastic transformation in stool samples from two independent cohorts of African Americans and Chinese patients with colorectal lesions. The metabolomic analysis of adenomas revealed low amino acids content. The microbiota in both cancer vs. normal tissues and adenoma vs. normal stool samples were different at the 16S rRNA gene level. Cross-mapping of metagenomic data led to 9 markers with significant discriminative power between normal and diseased specimens. These markers identified with Streptococcus sp. VT_162. Q-PCR data showed a statistically significant presence of this bacterium in advanced adenoma and cancer samples in an independent cohort of CRC patients. We defined metagenomic functions from Streptococcus sp. VT_162 with discriminative power among cancers vs. matched normal and adenomas vs. healthy subjects' stools. Streptococcus sp. VT_162 specific 16S rDNA was validated in an independent cohort. These findings might facilitate non-invasive screening for colorectal cancer.
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The Li-Fraumeni Syndrome (LFS), a genetically rare heterogeneous cancer syndrome, is characterized primarily by a germline p53 (TP53) gene mutation. We recently discovered a balanced reciprocal chromosomal translocation t(11;15)(q23;q15) in the non-cancerous skin fibroblasts of a bilateral breast cancer patient in LFS family. This prompted us to investigate the breakpoint region of the translocation, which uncovered a gene that encodes a Notch ligand, DLL4, (locus at 15q15.1), a key target in tumor vasculature. We analyzed DLL4 gene expression and protein level in LFS non-cancerous skin fibroblast cell lines and non-LFS cancer cell lines. DLL4 is abrogated in all the LFS cells and drastically down-regulated in breast (MCF7) and brain (IMR32) cancer cells and tumor tissue samples. However, DNA methylation studies revealed that DLL4 promoter is silenced only in MCF7 but not in LFS cells. We further investigated the regulation of DLL4 gene expression by ChIP assays, which demonstrated that p53 binds to DLL4 promoter through its association with CTCF, a chromosomal networking protein CCCTC binding factor. This implies a possible karyotype-phenotype correlation with respect to DLL4 in LFS and breast cancer initiation and progression. The drastic reduction or absence in the expression of DLL4 in LFS as well as breast and brain cancer cells is significant and supports the concept that this ligand may also play a role in cancer immune-surveillance; and its resuscitation in the tumor microenvironment may stimulate T-cell immunity and suppress tumor growth. Therefore, DLL4 may provide a strong platform as an immuno-therapeutic target in LFS and cancer patients.
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Epigênese Genética , Inativação Gênica , Peptídeos e Proteínas de Sinalização Intercelular/genética , Síndrome de Li-Fraumeni/genética , Células-Tronco Neoplásicas/metabolismo , Proteína Supressora de Tumor p53/genética , Proteínas Adaptadoras de Transdução de Sinal , Fator de Ligação a CCCTC/metabolismo , Proteínas de Ligação ao Cálcio , Linhagem Celular Tumoral , Metilação de DNA , Progressão da Doença , Feminino , Fibroblastos/metabolismo , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Mutação em Linhagem Germinativa , Humanos , Cariotipagem , Células MCF-7 , Fenótipo , Regiões Promotoras Genéticas , RNA Interferente Pequeno/metabolismo , Translocação GenéticaRESUMO
BACKGROUND: Historically, studies suggested that immigrants acquire the risk of colorectal cancer (CRC) as US-born persons within the same generation. CRC risk of immigrants is largely unknown in this era of cancer screening and widespread immigration. We investigated the association of place of birth and cancer beliefs with uptake of CRC screening. METHODS: The 2007 Health Information National Trends Survey was used and 4,299 respondents (weighted population size=81,896,392) who were 50 years and older (3,960 US-born and 339 foreign-born) were identified. We defined being current with CRC screening guidelines as the use of fecal occult blood test within 1 year, sigmoidoscopy within 5 years, or colonoscopy within 10 years. We compared being up-to-date with CRC screening among foreign-born versus US-born respondents. Logistic regression models were used to calculate odds ratios (OR) and 95% confidence intervals (CI). RESULTS: Overall, 2,594 (63.3%) US-born and 208 (52.8%) foreign-born respondents were current with CRC screening. Foreign-born respondents were less current in unadjusted model (OR 0.65; 95% CI: 0.50-0.85) but became non-statistically significant after adjustment (OR 0.79; 95% CI: 0.51-1.24). Respondents who believed that screening finds cancer when it is easy to treat (OR 2.85; 95% CI: 1.44-3.61), those who believed that cancer can be cured when detected early (OR 1.56; 95% CI: 1.20-2.00), and those who worry about getting cancer (OR 1.34; 95% CI: 1.10-1.61) were likely to be current with CRC screening. However, respondents with fatalistic beliefs were borderline less likely to be current (OR 0.82; 95% CI: 0.65-1.04). CONCLUSION: There is a need to improve education on CRC screening, particularly among foreign-born adults.
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The synthesis of new 3-cyano-2-substituted pyridines bearing various pharmacophores and functionalities at position 2 is described. The synthesized compounds were evaluated for their in vitro anti-cancer activities on five cancer cell lines using 5-FU as reference compound. The results revealed that the benzohydrazide derivative 9a induced growth inhibition in human breast cancer cell line MCF-7 with an IC50 value of 2 µM and it showed lower cytotoxicity on MCF-12a normal breast epithelial cells. Additionally, 9a induced apoptotic morphological changes and induced apoptosis in MCF-7 in a dose and time-dependent manner according to an enzyme linked immunosorbent apoptosis assay which is further confirmed by a TUNEL assay. Flow cytometric analysis indicated that 9a arrested MCF-7 cells in the G1 phase, which was further confirmed by increased expression of p21 and p27 and reduced expression of CDK2 and CDK4. Western blot data revealed significant upregulation of the expression of p53, Bax, caspase-3 and down-regulation of Bcl-2, Mdm-2 and Akt. Additionally, 9a increased the release of cytochrome c from mitochondria to cytoplasm which provokes the mitochondrial apoptotic pathway while it showed no significant change on the expression of the death receptor proteins procaspase-8, caspase-8 and FAS. Furthermore, 9a reduced the expression of phospho AKT and ß-catenin in dose dependent manner while inhibiting the expression of migration-related genes such as matrix metalloproteinase (MMP)-9 and vascular endothelial growth factor (VEGF). Our findings suggest that compound 9a could be considered as a lead structure for further development of more potent apoptosis inducing agents with anti-metastatic activities.
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Neoplasias da Mama/metabolismo , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Piridinas/síntese química , Piridinas/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Apoptose , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Células MCF-7 , Piridinas/química , Transdução de SinaisRESUMO
AIM: To determine compliance to colorectal cancer (CRC) screening guidelines among persons with a family history of any type of cancer and investigate racial differences in screening compliance. METHODS: We used the 2007 Health Information National Trends Survey and identified 1094 (27.4%) respondents (weighted population size = 21959672) without a family history of cancer and 3138 (72.6%) respondents (weighted population size = 58201479) with a family history of cancer who were 50 years and older. We defined compliance with CRC screening as the use of fecal occult blood testing within 1 year, sigmoidoscopy within 5 years, or colonoscopy within 10 years. We compared compliance with CRC screening among those with and without a family member with a history of cancer. RESULTS: Overall, those with a family member with cancer were more likely to be compliant with CRC screening (64.9% vs 55.1%; OR = 1.45; 95%CI: 1.20-1.74). The absolute increase in screening rates associated with family history of cancer was 8.2% among whites. Hispanics had lowest screening rates among those without family history of cancer 41.9% but had highest absolute increase (14.7%) in CRC screening rate when they have a family member with cancer. Blacks had the lowest absolute increase in CRC screening (5.3%) when a family member has a known history of cancer. However, the noted increase in screening rates among blacks and Hispanics when they have a family member with cancer were not higher than whites without a family history of cancer: (54.5% vs 58.7%; OR = 1.16; 95%CI: 0.72-1.88) for blacks and (56.7% vs 58.7%; OR = 1.25; 95%CI: 0.72-2.18) for Hispanics. CONCLUSION: While adults with a family history of any cancer were more likely to be compliant with CRC screening guidelines irrespective of race/ethnicity, blacks and Hispanics with a family history of cancer were less likely to be compliant than whites without a family history. Increased burden from CRC among blacks may be related to poor uptake of screening among high-risk groups.
RESUMO
Wild-type p53 is well known to induce cell cycle arrest and apoptosis to block aberrant cell growth. However, p53's unique role in apoptosis and cell proliferation in Li-Fraumeni Syndrome (LFS) has not been well elucidated. The aim of this study is to characterize the activity of wild-type p53 protein in LFS family dominated by a germline negative mutant p53. As expected, etoposide-treated wild-type p53-containing cell lines, LFS 2852 and control Jurkat, showed a greater rate of caspase- and annexin V-induced apoptotic cell death compared to the p53-mutant LFS 2673 cell line although mitochondrial and nuclear assays could not detect apoptosis in these organelles. The most intriguing part of the observation was the abnormal proliferation rate of the wild-type p53-containing cell line, which grew twice as fast as 2673 and Jurkat cells. This is important because apoptosis inducers acting through the mitochondrial death pathway are emerging as promising drugs against tumors where the role of p53 is not only to target gene regulation but also to block cell proliferation. This study casts a long shadow on the possible dysregulation of p53 mediators that enable cell proliferation. The deregulation of proliferation pathways represents an important anticancer therapeutic strategy for patients with the LFS phenotype.
RESUMO
Li-Fraumeni syndrome (LFS) is primarily characterized by development of tumors exhibiting germ-line mutations in the p53 gene. Cell lines developed from patients of a LFS family have decreased p53 activity as evidenced by the absence of apoptosis upon etoposide treatment. To test our hypothesis that changes in gene expression beyond p53 per se are contributing to the development of tumors, we compared gene expression in non-cancerous skin fibroblasts of LFS-affected (p53 heterozygous) vs. non-affected (p53 wild-type homozygous) family members. Expression analysis showed that several genes were differentially regulated in the p53 homozygous and heterozygous cell lines. We were particularly intrigued by the decreased expression (~88%) of a putative tumor-suppressor protein, caveolin-1 (Cav-1), in the p53-mutant cells. Decreased expression of Cav-1 was also seen in both p53-knockout and p21-knockout HTC116 cells suggesting that p53 controls Cav-1 expression through p21 and leading to the speculation that p53, Cav-1 and p21 may be part of a positive auto-regulatory feedback loop. The direct relationship between p53 and Cav-1 was also tested with HeLa cells (containing inactive p53), which expressed a significantly lower Cav-1 protein. A panel of nonfunctional and p53-deficient colon and epithelial breast cancer cell lines showed undetectable expression of Cav-1 supporting the role of p53 in the control of Cav-1. However, in two aggressively metastasizing breast cancer cell lines, Cav-1 was strongly expressed suggesting a possible role in tumor metastasis. Thus, there is a divergent control of Cav-1 expression as evidenced in non-cancerous Li-Fraumeni syndrome and some aggressive human cancer cell lines.
Assuntos
Caveolina 1/genética , Regulação Neoplásica da Expressão Gênica , Síndrome de Li-Fraumeni/metabolismo , Caveolina 1/metabolismo , Ciclo Celular , Linhagem Celular Tumoral , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Regulação para Baixo , Retroalimentação Fisiológica , Feminino , Expressão Gênica , Humanos , Síndrome de Li-Fraumeni/genética , Masculino , Análise de Sequência com Séries de Oligonucleotídeos , Transcriptoma , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Regulação para CimaRESUMO
Signal transducer and activator of transcription (Stat) 5 appears to play a vital role in prolactin (PRL)-induced cell differentiation and normal mammary gland development. We previously showed that PRL-activated Stat5a induced expression of E-cadherin-beta-catenin complex in vitro and in xenotransplant tumors in vivo led to inhibition of breast cancer invasion. In the present study, we show that human breast cancer cells co-overexpressing Stat5a and its tyrosine kinase (Jak) 2 cultured in three-dimensional (3D) Matrigel culture demonstrate changes consistent with induction of mesenchymal-epithelial redifferentiation. Jak2 and Stat5a-co-overexpressing cells treated with cocktail (PRL, dexamethasone, and insulin), effectively reverse epithelial-mesenchymal transition by stimulating 3D organoids more reminiscent of the acinar growth of normal mammary epithelial cells, compared with cells overexpressing only Stat5a or Jak2. In contrast, dominant-negative dominant-negative-Stat5 blocks 3D organoid formation, causing cells to grow in layers instead. Hyperactivation of Jak2 and Stat5a in T-47D cells induces alveolar-like structures, mamospheres, with marked lumen formation through central apoptosis and restores a polarized epithelial phenotype. However, Jak2 and Stat5a overexpression in BT-20 cells induces partially differentiated 3D organoids with no central lumen, but effectively re-expresses estrogen receptor alpha. Jak2 and Stat5a-induced 3D differentiated organoids are accompanied by increased expression of E-cadherin, zonula occludens-1, and cytokeratins 8 and 18, and decreased levels of vimentin and Snail, indicating a shift from a mesenchymal phenotype toward an epithelial phenotype. Collectively, Jak2 and Stat5a co-overexpression cooperatively reverses epithelial-mesenchymal transition and promotes differentiation in human breast cancer cells, which may provide a mechanism to explain the invasive suppressor role of PRL-activated Stat5a in mammary cancer cells.
Assuntos
Neoplasias da Mama/metabolismo , Células Epiteliais/citologia , Janus Quinase 2/metabolismo , Mesoderma/citologia , Fator de Transcrição STAT5/metabolismo , Transdução de Sinais , Proteínas Supressoras de Tumor/metabolismo , Neoplasias da Mama/enzimologia , Neoplasias da Mama/patologia , Diferenciação Celular , Linhagem Celular Transformada , Linhagem Celular Tumoral , Células Epiteliais/metabolismo , Feminino , Humanos , Mesoderma/metabolismoRESUMO
Li-Fraumeni Syndrome (LFS) is characterized by early-onset carcinogenesis involving multiple tumor types and shows autosomal dominant inheritance. Approximately 70% of LFS cases are due to germline mutations in the TP53 gene on chromosome 17p13.1. Mutations have also been found in the CHEK2 gene on chromosome 22q11, and others have been mapped to chromosome 11q23. While characterizing an LFS family with a documented defect in TP53, we found one family member who developed bilateral breast cancer at age 37 yet was homozygous for wild-type TP53. Her mother also developed early-onset primary bilateral breast cancer, and a sister had unilateral breast cancer and a soft tissue sarcoma. Cytogenetic analysis using fluorescence in situ hybridization of a primary skin fibroblast cell line revealed that the patient had a novel balanced reciprocal translocation between the long arms of chromosomes 11 and 15: t(11;15)(q23;q15). This translocation was not present in a primary skin fibroblast cell line from a brother with neuroblastoma, who was heterozygous for the TP53 mutation. There was no evidence of acute lymphoblastic leukemia in either the patient or her mother, although a nephew did develop leukemia and died in childhood. These data may implicate the region at breakpoint 11q23 and/or 15q15 as playing a significant role in predisposition to breast cancer development.