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1.
Pneumonia (Nathan) ; 14(1): 8, 2022 Nov 25.
Article in English | MEDLINE | ID: mdl-36424653

ABSTRACT

BACKGROUND: There is a knowledge gap of specific characteristics linked to disease severity of the different COVID-19 waves, especially in underserved populations. We compared the demographic and clinical factors associated with SARS-CoV-2-infected patients admitted to the intensive care unit (ICU) during the Omicron and Alpha waves. METHODS: An observational study comparing two COVID-19 waves was conducted in Brooklyn, NY. Twenty-seven ICU admitted patients with a positive COVID-19 test result during the period of November 1, 2021, to January 31, 2022, ("Omicron wave") were compared to 271 COVID-19 patients who received ICU consults during the Alpha wave, the period from March 28, 2020, to April 30, 2020. RESULTS: The Omicron wave had a 55.6% mortality rate compared to a 67.2% mortality rate in the Alpha wave. For the non-survivors, there were more females (66.7%) in the Omicron wave, while the trend was reversed in the Alpha wave (38.5%). Most of the patients seen were Black (> 85%) in both waves. A bivariate comparison of the two waves found that patients in the Omicron wave had overall significantly lower ALT levels (p = 0.03) and higher monocyte % (p = 0.005) compared to the patients in the Alpha wave. In the multivariate analysis, adjusting for age and sex, increasing levels of HCO3- were significantly associated with reduced mortality in the Omicron wave (OR: 0.698; 95% CI: 0.516 - 0.945; p = 0.02). Also, multivariable analyses using both waves combined found that neutrophil % was significantly associated with increased mortality (OR: 1.05; 95% CI: 1.02 - 1.09; p = 0.006) while lymphocyte % was significantly associated with reduced mortality (OR: 0.946; 95% CI: 0.904 - 0.990; p = 0.018). CONCLUSIONS: The COVID-19-positive ICU patients in the Omicron wave experienced less severe outcomes than those of the Alpha wave. In contrast to the Alpha variant, the Omicron variant exhibited enhanced infectivity and disease severity in females.

2.
J Lipid Res ; 63(4): 100185, 2022 04.
Article in English | MEDLINE | ID: mdl-35202607

ABSTRACT

The LDL receptor-related protein 1 (LRP1) partakes in metabolic and signaling events regulated in a tissue-specific manner. The function of LRP1 in airways has not been studied. We aimed to study the function of LRP1 in smoke-induced disease. We found that bronchial epithelium of patients with chronic obstructive pulmonary disease and airway epithelium of mice exposed to smoke had increased LRP1 expression. We then knocked out LRP1 in human bronchial epithelial cells in vitro and in airway epithelial club cells in mice. In vitro, LRP1 knockdown decreased cell migration and increased transforming growth factor ß activation. Tamoxifen-inducible airway-specific LRP1 knockout mice (club Lrp1-/-) induced after complete lung development had increased inflammation in the bronchoalveolar space and lung parenchyma at baseline. After 6 months of smoke exposure, club Lrp1-/- mice showed a combined restrictive and obstructive phenotype, with lower compliance, inspiratory capacity, and forced expiratory volume0.05/forced vital capacity than WT smoke-exposed mice. This was associated with increased values of Ashcroft fibrotic index. Proteomic analysis of room air exposed-club Lrp1-/- mice showed significantly decreased levels of proteins involved in cytoskeleton signaling and xenobiotic detoxification as well as decreased levels of glutathione. The proteome fingerprint created by smoke eclipsed many of the original differences, but club Lrp1-/- mice continued to have decreased lung glutathione levels and increased protein oxidative damage and airway cell proliferation. Therefore, LRP1 deficiency leads to greater lung inflammation and damage and exacerbates smoke-induced lung disease.


Subject(s)
Airway Remodeling , Low Density Lipoprotein Receptor-Related Protein-1 , Oxidative Stress , Smoke , Animals , Epithelium/metabolism , Glutathione/metabolism , Humans , Low Density Lipoprotein Receptor-Related Protein-1/genetics , Low Density Lipoprotein Receptor-Related Protein-1/metabolism , Lung/metabolism , Mice , Proteomics , Smoke/adverse effects
3.
Medicina (Kaunas) ; 57(10)2021 Oct 07.
Article in English | MEDLINE | ID: mdl-34684107

ABSTRACT

Background and Objectives: This study aimed to identify demographic and clinical factors at the time of critical care consultation associated with mortality or intensive care unit acceptance in a predominantly Afro-Caribbean population during the first wave of the COVID19 pandemic. Materials and Methods: This retrospective, single-center observational cohort study included 271 COVID19 patients who received a critical care consult between March 11 and April 30, 2020 during the first wave of the COVID19 pandemic at State University of New York Downstate Health Sciences University. Results: Of the 271 patients with critical care consults, 33% survived and 67% expired. At the bivariate level, age, blood urea nitrogen, and blood neutrophil percentage were significantly associated with mortality (mean age: survivors, 61.62 ± 1.50 vs. non-survivors, 68.98 ± 0.85, p < 0.001). There was also a significant association between neutrophil% and mortality in the univariate logistic regression model (quartile 4 vs. quartile 1: odd ratio 2.73, 95% confidence interval (1.28-5.82), p trend = 0.044). In the multivariate analyses, increasing levels of procalcitonin and C-reactive protein were significantly associated with mortality, adjusting for age, sex, and race/ethnicity (for procalcitonin quartile 4 vs. quartile 1: odds ratio 5.65, 95% confidence interval (2.14-14.9), p trend < 0.001). In contrast, higher platelet levels correlated with significantly decreased odds of mortality (quartile 4 vs. quartile 1, odds ratio 0.47, 95% CI (0.22-0.998), p trend = 0.010). Of these factors, only elevated procalcitonin levels were associated with intensive care unit acceptance. Conclusions: Procalcitonin showed the greatest magnitude of association with both death and likelihood of intensive care unit acceptance at the bivariate level. Our data suggests that procalcitonin reflects pneumonia severity during COVID-19 infection. Thus, it may help the intensivist identify those COVID19 patients who require intensive care unit level care.


Subject(s)
COVID-19 , Procalcitonin , Aged , Humans , Intensive Care Units , Middle Aged , Prognosis , Retrospective Studies , SARS-CoV-2
4.
SAGE Open Med ; 9: 20503121211012521, 2021.
Article in English | MEDLINE | ID: mdl-33996084

ABSTRACT

OBJECTIVES: Sepsis is one of the leading causes of morbidity and mortality within the healthcare system and remains a diagnostic and therapeutic challenge. A major issue in the diagnosis of sepsis is understanding the pathophysiologic mechanism, which revolves around host immune system activation and dysregulated responses. African Americans are more likely to experience severe sepsis with higher mortality rates compared to the general population. This pilot study characterized multiple inflammatory markers and proteases in plasma of primarily African American and Afro-Caribbean patients with mild sepsis. METHODS: Plasma was collected from 16 healthy controls and 15 subjects presenting with sepsis, on admission, and again upon resolution of the signs of sepsis, defined as a resolution of sepsis criteria. Plasma samples were analyzed for cytokines, chemokines, and proteases using multiplex bead assays. RESULTS: Elevated levels of granulocyte colony-stimulating factor, interleukin-10, interleukin-15, interleukin-1 receptor antagonist, interleukin-8, interferon gamma-induced protein 10, monocyte chemoattractant protein-1, matrix metallopeptidase 12, and cathepsin S were identified in plasma from sepsis patients on admission compared to control subjects. Interleukin-6, interleukin-8, granulocyte colony-stimulating factor, and cathepsin S were reduced in sepsis patients upon clinical resolution of sepsis. CONCLUSION: These findings profile the circulating inflammatory cytokines, chemokines, and proteases in African Americans and Afro-Caribbean patients during sepsis. The role of these targets in sepsis needs addressing in this patient population.

6.
Medicine (Baltimore) ; 99(51): e22559, 2020 Dec 18.
Article in English | MEDLINE | ID: mdl-33371055

ABSTRACT

RATIONALE: Lung cancer is a leading cause of cancer-related deaths. Smoking is major risk factor for initial and subsequent lung cancer especially in active smokers. Treatment of subsequent lung cancer depends on whether it is synchronous or metachronous. We report a rare case of triple metachronous lung cancer and review of literature of patients with triple metachronous cancers. This will be the second case reported of triple metachronous lung cancer. PATIENT CONCERNS: A 60-year-old male, active smoker with diabetes mellitus, chronic obstructive pulmonary disease (COPD) and peripheral arterial disease presented with cough and hemoptysis. Initial computed tomography (CT) scan showed right upper lobe spiculated mass. DIAGNOSIS: He underwent transthoracic needle biopsy for right upper lobe mass, showing primary lung adenocarcinoma (ADC)-Stage-IIIA. He continued to smoke and 9-years later had new left upper lobe spiculated nodule, which on surgical resection showed squamous cell carcinoma (SCC)-Stage-IA1. Despite counselling on smoking cessation, he was unable to quit. Six months later, he presented with shortness of breath and CT chest showing right hilar adenopathy in right upper and lower lobes. He underwent transbronchial biopsies of lesion which showed small cell lung carcinoma (SCLC). INTERVENTIONS: His initial lung ADC-Stage-IIIA, was treated with chemotherapy, weekly thoracic radiation and additional chemotherapy cycles. Nine years later, his left upper lobe mass showing SCC-Stage-IA1 was deemed curative after apical resection and he was kept on surveillance. Six months later, after diagnosis of SCLC in right upper and lower lobe, patient was not a candidate for systemic chemotherapy due to poor performance status and opted for hospice care. OUTCOMES: His initial lung ADC-Stage-IIIA showed complete radiological response with chemotherapy and radiation. Subsequent SCC-Stage-IA1 was deemed curative after resection. Due to his poor performance status, he was not a candidate for chemotherapy for SCLC and patient opted for hospice care. LESSONS: Smoking is a major risk factor for developing lung cancer and with continued smoking, patients are at higher risk for developing subsequent primary lung cancers. We recommend, patients with lung cancer must quit smoking, and those who do not, should remain on long-term surveillance.


Subject(s)
Adenocarcinoma/pathology , Carcinoma, Squamous Cell/pathology , Lung Neoplasms/pathology , Small Cell Lung Carcinoma/pathology , Tobacco Use/pathology , Humans , Male , Middle Aged
7.
Sci Rep ; 10(1): 16350, 2020 10 01.
Article in English | MEDLINE | ID: mdl-33005006

ABSTRACT

Chronic rhinosinusitis (CRS) is a common condition associated with inflammation and tissue remodeling of the nose and paranasal sinuses, frequently occurring with nasal polyps and allergies. Here we investigate inflammation and the protease profile in nasal tissues and plasma from control non-CRS patients and CRS patients. Gene expression for several cytokines, proteases, and antiproteases was quantified in nasal tissue from non-CRS and CRS subjects with nasal polyps. Elevated expression of S100A9, IL1A, MMP3, MMP7, MMP11, MMP25, MMP28, and CTSK was observed in tissue from CRS subjects with nasal polyps compared to control tissue. Tissue protein analysis confirmed elevated levels of these targets compared to controls, and increased MMP3 and MMP7 observed in CRS subjects with nasal polyps compared to CRS subjects without polyps. Plasma concentrations of MMP3 and MMP7 were elevated in the CRS groups compared to controls. The nasal cell line, CCL-30, was exposed to S100A9 protein, resulting in increased MMP3, MMP7, and CTSK gene expression and elevated proliferation. Silencing MMP3 significantly reduced S100A9-mediated cell proliferation. Therefore, the elevated expression of S100A9 and MMPs are observed in CRS nasal tissue and S100A9 stimulated MMP3 responses to contribute to elevated nasal cell proliferation.


Subject(s)
Calgranulin B/metabolism , Matrix Metalloproteinases/metabolism , Nasal Mucosa/metabolism , Nasal Polyps/metabolism , Rhinitis/metabolism , Sinusitis/metabolism , Adult , Cytokines/metabolism , Female , Humans , Male , Middle Aged
8.
Acad Emerg Med ; 27(6): 520-522, 2020 06.
Article in English | MEDLINE | ID: mdl-32096893
9.
IDCases ; 10: 102-104, 2017.
Article in English | MEDLINE | ID: mdl-29062711

ABSTRACT

Citrobacter koseri is a gram-negative bacillius that belongs to the Enterobacteriaceae family. It is an uncommon pathogen that typically causes meningitis and brain abscesses in children, however central nervous system (CNS) infections are rarely found in adults. We present a case of C. koseri meningitis in an immunocompetent adult secondary to intestinal micro-perforation caused by Strongyloides A 76-year-old man admitted for asthma exacerbation developed septic shock. A lumbar puncture revealed bacterial meningitis. Blood and CSF cultures grew Citrobacter koseri with identical susceptibilities, suggesting infection by one strain. Despite broad-spectrum antibiotics, the patient expired of multi-organ failure. Autopsy identified diffuse alveolar hemorrhage as the immedi ate cause of death with a heavy burden of Strongyloides stercoralis in his gastrointestinal system, lungs, and meninges. Citrobacter koseri is a gram-negative bacillus of the Enterobacteriaceae family. It is an uncommon pathogen that typically causes meningitis and brain abscesses in children. Infections in adults occur in immunocompromised hosts or instances where an insult creates a port of entry. This is the first documented case of C.koseri sepsis in an immunocompetent host associated with Strongyloides Hyperinfection Syndrome (SHS), where massive parasitic intestinal invasion reaches pulmonary circulation and perforates the alveolar membrane. This case highlights that presence of rare enterobacterial infections should prompt consideration of differentials including SHS.

10.
Gene ; 443(1-2): 55-63, 2009 Aug 15.
Article in English | MEDLINE | ID: mdl-19450668

ABSTRACT

RASSF1A, which is frequently found inactivated in human cancers, is revealed as a tumor suppressor gene in nasopharyngeal carcinoma (NPC). Using RASSF1A-expressing (NP69 and HK-1) and non-RASSF1A-expressing (C666-1) cell models, the transcriptional regulation of RASSF1A was studied. By deletion analysis of 3.1 kb of 5' flanking region, the core promoter of RASSF1A was identified in the region between -431 and -1 upstream of the translation start site. Sequence analysis of this core promoter revealed several putative transcription factor binding sties. Using NP69 cells and by block replacement mutagenesis, the presence of three functional GC-boxes were identified, to which by competitive and supershift electrophoretic mobility shift assays (EMSA), the in vitro bindings of Sp1 and Sp3 were suggested. The in vivo functions of Sp-proteins in regulating RASSF1A gene were then investigated by overexpression studies; among the tested Sp-proteins, Sp1 or Sp3, but not Sp4, was able to augment promoter activities. More interestingly, co-expression of Sp1 and Sp3 could synergistically enhance RASSF1A promoter function. UV irradiation induces oxidation stresses and hence is routinely used to investigate expressions of oncogenes and tumor suppressors. In this report, upon UV irradiation, the RASSF1A promoter activity and endogenous transcript levels were found to be reduced. By chromatin immunoprecipitation (ChIP) and EMSA, we demonstrated that the binding of Sp1 and Sp3 onto -431 to -202 were significantly reduced after UV irradiation. This UV-mediated effect on RASSF1A promoter, as shown by specific inhibitors that interrupt cellular pathways, is MEK1-, but not JNK-dependent. In summary, our data provided a simple model to explain the potential development of NPC, via silencing of the tumor suppressor RASSF1A by reduced bindings of activators Sp1 and Sp3 onto the GC-boxes in the core promoter of the gene.


Subject(s)
Down-Regulation , Nasopharyngeal Neoplasms/metabolism , Tumor Suppressor Proteins/metabolism , Cell Line, Tumor , CpG Islands , Humans , MAP Kinase Kinase 1/metabolism , MAP Kinase Kinase 4/metabolism , Mutagenesis, Site-Directed , Promoter Regions, Genetic , Sp Transcription Factors/metabolism , Tumor Suppressor Proteins/genetics , Ultraviolet Rays
11.
Genes Chromosomes Cancer ; 46(2): 171-80, 2007 Feb.
Article in English | MEDLINE | ID: mdl-17099870

ABSTRACT

Deletion of the short arm of chromosome 3 is a common event in nasopharyngeal carcinoma (NPC), suggesting that one or more tumor suppressor genes at 3p are involved in this cancer. DLEC1, Deleted in Lung and Esophageal Cancer 1, located at 3p22.2, was recently identified as a candidate tumor suppressor gene in lung, esophageal, and renal cancers. In this study, we investigated the involvement of DLEC1 in the development of NPC. Down-regulation of DLEC1 and promoter hypermethylation were observed in all NPC cell lines and xenografts but not in normal nasopharyngeal epithelial cells. Promoter hypermethylation of DLEC1 was also detected in 30 of 42 (71%) NPC primary tumors. Treatment of NPC cell lines with demethylating agent or histone deacetylase inhibitor resulted in restoration of DLEC1 expression. Overexpression of DLEC suppressed growth and reduced invasiveness of NPC cells. Furthermore, the tumorigenic potential of DLEC1 expressing NPC cells was highly reduced in nude mice. Taken together, our results strongly suggest that silencing of DLEC1 expression by promoter hypermethylation and histone deacetylation may be important in NPC tumorigenesis.


Subject(s)
Carcinoma/genetics , Epigenesis, Genetic , Gene Silencing , Nasopharyngeal Neoplasms/genetics , Tumor Suppressor Proteins/antagonists & inhibitors , Tumor Suppressor Proteins/genetics , Adult , Aged , Animals , Carcinoma/metabolism , Cell Line, Tumor , Cell Transformation, Neoplastic/genetics , Female , Histones/metabolism , Humans , Male , Mice , Mice, Nude , Middle Aged , Nasopharyngeal Neoplasms/etiology , Nasopharyngeal Neoplasms/metabolism , Promoter Regions, Genetic , Transplantation, Heterologous , Tumor Suppressor Proteins/biosynthesis
12.
Neoplasia ; 7(1): 67-74, 2005 Jan.
Article in English | MEDLINE | ID: mdl-15720818

ABSTRACT

Aberrant retinoid signaling in human cancers is extending from the nucleus to the cytoplasm. Recently, we have demonstrated frequent epigenetic inactivation of a retinoic acid receptor (RAR), RARbeta2, in nasopharyngeal carcinoma (NPC). To further explore targets contributing to aberrant retinoid signaling in NPC, the expression of cellular retinol-binding proteins (CRBPs), cellular retinoic acid-binding proteins (CRABPs), RARs, and retinoid X receptors (RXRs) was examined. Apart from RARbeta2, transcriptional silencing of two CRBPs, CRBPI and CRBPIV, was observed in NPC cell lines and xenografts. Hypermethylation of CRBPI and CRBPIV CpG islands was found to be closely correlated with the loss of expression. Treatment with the DNA methyltransferase inhibitor, 5-aza-2'-deoxycytidine, resulted in reexpression of CRBP1 and CRBPIV gene expression in NPC cell lines. Both CRBPI and CRBPIV hypermethylations were also observed in 43/48 (87.8%) and 26/48 (54.2%) primary NPC tumors, respectively. Here, we reported for the first time that CRBPIV was transcriptionally inactivated by promoter hypermethylation in human cancer. Simultaneous methylation of CRBPI, CRBPIV, and RARbeta2 was commonly found in NPC primary tumors. Our findings implied that epigenetic disruption of the CRBPs, CRBPI and CRBPIV, is important in NPC tumorigenesis and may contribute to the loss of retinoic acid responsiveness in cancer.


Subject(s)
Azacitidine/analogs & derivatives , CpG Islands , DNA Methylation , Nasopharyngeal Neoplasms/genetics , Promoter Regions, Genetic/genetics , Retinoids/pharmacology , Retinol-Binding Proteins/genetics , Adult , Aged , Animals , Azacitidine/pharmacology , DNA, Neoplasm/genetics , DNA, Neoplasm/metabolism , Decitabine , Female , Gene Expression Regulation, Neoplastic , Humans , Male , Mice , Middle Aged , Nasopharyngeal Neoplasms/metabolism , Nasopharyngeal Neoplasms/pathology , Nasopharynx/metabolism , Retinol-Binding Proteins/metabolism , Retinol-Binding Proteins, Cellular , Transplantation, Heterologous , Tumor Cells, Cultured
13.
Int J Cancer ; 113(3): 386-92, 2005 Jan 20.
Article in English | MEDLINE | ID: mdl-15455391

ABSTRACT

Tazarotene-induced gene 1 (TIG1) and Tazarotene-induced gene 3 (TIG3) are retinoid acid (RA) target genes as well as candidate tumor suppressor genes in human cancers. In our study, we have investigated the expression of TIG1 and TIG3 in nasopharyngeal carcinoma (NPC). Loss of TIG1 expression was found in 80% of NPC cell lines and 33% of xenografts, whereas TIG3 was expressed in all NPC samples and immortalized nasopharyngeal epithelial cells. In order to elucidate the epigenetic silencing of TIG1 in NPC, the methylation status of TIG1 promoter was examined by genomic bisulfite sequencing and methylation-specific PCR (MSP). We have detected dense methylation of TIG1 5'CpG island in the 5 TIG1-negative NPC cell lines and xenograft (C666-1, CNE1, CNE2, HONE1 and X666). Partial methylation was observed in 1 NPC cell line HK1 showing dramatic decreased in TIG1 expression. Promoter methylation was absent in 2 TIG1-expressed NPC xenografts and the normal epithelial cells. Restoration of TIG1 expression and unmethylated alleles were observed in NPC cell lines after 5-aza-2'-deoxycytidine treatment. Moreover, the methylated TIG1 sequence was detected in 39 of 43 (90.7%) primary NPC tumors by MSP. In conclusion, our results showed that TIG1 expression is lost in the majority of NPC cell lines and xenografts, while promoter hypermethylation is the major mechanism for TIG1 silencing. Furthermore, the frequent epigenetic inactivation of TIG1 in primary NPC tumors implied that it may play an important role in NPC tumorigenesis.


Subject(s)
Azacitidine/analogs & derivatives , DNA Methylation , Gene Silencing , Nasopharyngeal Neoplasms/genetics , Promoter Regions, Genetic/genetics , Retinoids/pharmacology , Transcription Factors/genetics , Animals , Azacitidine/pharmacology , Cells, Cultured , DNA Modification Methylases/antagonists & inhibitors , Decitabine , Enzyme Inhibitors/pharmacology , Gene Expression Regulation, Neoplastic/drug effects , Humans , Mediator Complex , Mice , Nasopharyngeal Neoplasms/metabolism , Nasopharyngeal Neoplasms/pathology , Nasopharynx/metabolism , Nasopharynx/pathology , Receptors, Retinoic Acid/genetics , Reverse Transcriptase Polymerase Chain Reaction , Transplantation, Heterologous
14.
Oncol Rep ; 12(4): 781-7, 2004 Oct.
Article in English | MEDLINE | ID: mdl-15375500

ABSTRACT

Ras-association domain family of proteins (RASSF) is characterized by the Ras-association (RA) domain at the C-terminal. Frequent inactivation of RASSF1A gene in human cancers suggests that other members of the family may also play an important role in tumorigenesis. By in silico gene searches, the number of RASSF family members is increasing. Two new members of RASSF family, RASSF4/AD037 and NORE1, were recently identified. While the status of RASSF4/AD037 is poorly understood, methylation of NORE1A was reported to be common in human cancers. In this study, we aimed to investigate the expression and methylation status of RASSF4/AD037 and NORE1 in nasopharyngeal carcinoma (NPC) in which RASSF1A is frequently inactivated by promoter hypermethylation. Our results showed that expression of RASSF4/AD037 was lost in 12.5% (1/8) of NPC cell lines/xenografts. Bisulfite sequencing analysis revealed dense methylation in the promoter region of RASSF4/AD037 in the cell line. Restoration of RASSF4/AD037 mRNA was observed by treatment with a demethylating agent. Moreover, methylation of primary NPC was found in 5% (1/20) of the samples examined. For NORE1A, partial methylation was detected in 37.5% (3/8) of NPC cell lines/xenografts while expression of NORE1A was found in all NPC cell lines/xenografts. No aberrant methylation of NORE1A was observed in 20 primary tumors. In summary, epigenetic inactivation of RASSF4/AD037 and NORE1A is rare in NPC, suggesting that these two RASSF family members may not be critical targets for gene inactivation during the tumorigenesis of NPC.


Subject(s)
DNA Methylation , Nasopharyngeal Neoplasms/genetics , Promoter Regions, Genetic/genetics , Tumor Suppressor Proteins/genetics , Adaptor Proteins, Signal Transducing , Amino Acid Sequence , Apoptosis , Apoptosis Regulatory Proteins , Azacitidine/pharmacology , DNA, Neoplasm/genetics , Epigenesis, Genetic , Gene Silencing , Humans , Molecular Sequence Data , Monomeric GTP-Binding Proteins/genetics , RNA, Messenger/genetics , RNA, Messenger/metabolism , Sequence Homology, Amino Acid , Transplantation, Heterologous , Tumor Cells, Cultured
15.
Int J Cancer ; 109(6): 839-47, 2004 May 10.
Article in English | MEDLINE | ID: mdl-15027117

ABSTRACT

Deletion on the short arm of chromosome 3 is one of the most important genetic abnormalities in the tumorigenesis of nasopharyngeal carcinoma (NPC). Both physical mapping and functional studies have targeted an NPC-related tumor suppressor gene(s) to chromosome 3p21.3. We have reported recently that RASSF1A gene, located on a 120-kb minimal deletion region on 3p21.3, was frequently inactivated by promoter hypermethylation in NPC. We further confirmed that RASSF1A is the critical target tumor suppressor from 3p21.3, with the evidence that loss of expression and aberrant methylation of the other 8 candidate genes/transcripts (HYAL2, FUS1, RASSF1C, BLU, NPRL2, 101F6, PL6 and CACNA2D2) in this 120-kb region were rare in NPC samples. The contribution of RASSF1A in NPC tumorigenesis was investigated by restoring its expression in a RASSF1A deficient cell line, C666-1. Transient transfection of wild-type RASSF1A resulted in marked growth inhibition in NPC cells. Isolated stable clones expressing wild-type RASSF1A demonstrated retarded cell proliferation in vitro. Soft-agar assay also showed decreased number and sizes of colony formed in these clones. In vivo nude mice assay demonstrated the dramatic reduction of tumorigenic potential in the RASSF1A-transfected clones. Our results provide strong evidence to support RASSF1A as a target tumor suppressor gene on 3p21.3 in NPC.


Subject(s)
Chromosomes, Human, Pair 3/genetics , Gene Expression Regulation, Neoplastic , Genes, Tumor Suppressor , Nasopharyngeal Neoplasms/genetics , Tumor Suppressor Proteins/genetics , Animals , Azacitidine/pharmacology , Biomarkers, Tumor/genetics , Biomarkers, Tumor/metabolism , Cell Cycle , Cell Division/genetics , Colony-Forming Units Assay , DNA Methylation , Female , Humans , Mice , Mice, Inbred BALB C , Mice, Nude , Nasopharyngeal Neoplasms/metabolism , Nasopharyngeal Neoplasms/pathology , Nasopharynx/metabolism , Nasopharynx/pathology , Reverse Transcriptase Polymerase Chain Reaction , Transduction, Genetic , Tumor Cells, Cultured , Tumor Suppressor Proteins/metabolism , Xenograft Model Antitumor Assays
16.
Mol Carcinog ; 38(4): 170-8, 2003 Dec.
Article in English | MEDLINE | ID: mdl-14639656

ABSTRACT

Deletion of 11q23 is a common genetic aberration in nasopharyngeal carcinoma (NPC). Multiple candidate tumor suppressor genes (TSG) were mapped to this region but few of them were investigated in NPC. TSLC1 (tumor suppressor in lung cancer) is recently reported to be a putative TSG on 11q23. This gene was found to be inactivated by promoter hypermethylation in non-small cell lung carcinoma (NSCLC), liver cancer, and breast cancer. To study the role of TSLC1 gene in NPC tumorigenesis, we screened for mutations and aberrant methylation of TSLC1 gene in 5 NPC cell lines, 3 NPC xenografts, and 38 primary NPC cases. No somatic mutations of TSLC1 were detected in the NPC samples, but a 9-bp (CCACCACCA) deletion in exon 8 was found in a primary NPC and its corresponding blood sample. Bisulfite sequencing revealed aberrant methylation of TSLC1 promoter in four NPC cell lines. Loss of TSLC1 gene expression was found in two cell lines (HK-1 and CNE-2) with dense methylation. Expression of this gene was restored in these cell lines after treatment with demethylating agent 5-aza-2'-deoxycytidine. Our results showed that silencing of TSLC1 gene expression in NPC was associated with promoter hypermethylation. Promoter hypermethylation of TSLC1 gene was further illustrated in 34.2% (13/38) of primary NPCs. No aberrant promoter methylation was found in any of the four investigated normal nasopharyngeal epithelia. Frequent epigenetic inactivation of TSLC1 gene in NPC suggested that this gene is one of the target tumor suppressor genes of this endemic cancer.


Subject(s)
Azacitidine/analogs & derivatives , DNA Methylation , Immunoglobulins , Membrane Proteins , Nasopharyngeal Neoplasms/genetics , Promoter Regions, Genetic , Proteins/genetics , Adult , Aged , Animals , Azacitidine/pharmacology , Base Sequence , Cell Adhesion Molecule-1 , Cell Adhesion Molecules , Chromosomes, Human, Pair 11/genetics , DNA Modification Methylases/antagonists & inhibitors , DNA Primers/chemistry , DNA, Neoplasm/genetics , Decitabine , Enzyme Inhibitors/pharmacology , Female , Gene Expression Regulation, Neoplastic , Gene Silencing , Genes, Tumor Suppressor , Humans , Loss of Heterozygosity , Male , Mice , Microsatellite Repeats , Middle Aged , Molecular Sequence Data , Mutation , Nasopharyngeal Neoplasms/metabolism , Nasopharynx/metabolism , Proteins/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Sequence Deletion , Transplantation, Heterologous , Tumor Cells, Cultured , Tumor Suppressor Proteins
17.
Anticancer Drugs ; 13(9): 957-64, 2002 Oct.
Article in English | MEDLINE | ID: mdl-12394259

ABSTRACT

The use of cisplatin as a potential radiosensitizer in nasopharyngeal carcinoma (NPC) has produced encouraging results in clinical trials. In order to provide information on improving the design of clinical treatments, we investigated the effect of cisplatin dose, and the time interval and sequence between administration of cisplatin and radiation on cell survival of two NPC cell lines, CNE1 and SUNE1. When cisplatin was applied first, an exposure time of 24 h resulted in up to 2.6-fold increase in cell death and 7-fold increase in radiation effect (cell survival after cisplatin/cell survival after cisplatin plus radiation) in the cisplatin-radiation combination treatment compared to the cells treated with cisplatin for 4 h. When radiation was applied first, a shorter interval time of 4 h followed by cisplatin treatment resulted in up to 3-fold increase in cell death and a 3-fold enhanced radiation effect over longer time intervals of 24 h. By changing the order of radiation and cisplatin treatment alone, a 2-fold difference in radiation effect was observed. The differential cytotoxicity was partially explained by the alterations in cell cycle distribution. Our results indicate the importance of scheduling the radiation and cisplatin combination regimens on the survival of NPC cells.


Subject(s)
Cisplatin/therapeutic use , Nasopharyngeal Neoplasms/drug therapy , Nasopharyngeal Neoplasms/radiotherapy , Radiation-Sensitizing Agents/administration & dosage , Cell Cycle/drug effects , Cell Cycle/radiation effects , Cell Survival/drug effects , Cell Survival/radiation effects , Cisplatin/administration & dosage , Combined Modality Therapy , Dose-Response Relationship, Drug , Dose-Response Relationship, Radiation , Drug Administration Schedule , Drug Evaluation, Preclinical , Humans , Nasopharyngeal Neoplasms/pathology , Tumor Cells, Cultured , Tumor Stem Cell Assay
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