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2.
Front Physiol ; 9: 1321, 2018.
Article in English | MEDLINE | ID: mdl-30294284

ABSTRACT

Introduction: Metabolic syndrome (MetS) is a multiplex cardiometabolic manifestation associated with type 2 diabetes mellitus and cardiovascular diseases. Yoga training has been shown to alleviate MetS. Recently, circulatory ghrelin profile was demonstrated to be associated with MetS. This study examined the effects of 1 year of yoga training on ß-cell function and insulin resistance, and the involvement of metabolic peptides, including unacylated ghrelin (UnAG), acylated ghrelin (AG), obestatin, growth hormone (GH), and insulin, in the beneficial effects of yoga training in centrally obese adults with MetS. Methods: This was a follow up study, in which data of risk factors of MetS, physical performance tests [resting heart rate (HR), chair stand test (CS), chair sit and reach test (CSR), back scratch test (BS), and single leg stand tests (SLS)] and serum samples of 79 centrally obese MetS subjects aged 58 ± 8 years (39 subjects received 1-year yoga training and 40 subjects received no training) were retrieved for analyses. ß-cell function and insulin resistance were examined by Homeostasis Model Assessment (HOMA). Circulating levels of UnAG, AG, obestatin, GH, and insulin were determined by enzyme-linked immunosorbent assay using fasting serum samples. Generalized estimating equation analysis and Mann-Whitney U-test were used to detect statistically significant differences between groups. Results: Waist circumference (WC) was significantly decreased after yoga intervention (control: +2%; yoga: -4%). Significant improvements in HR (control: +2%; yoga: -5%), CS (control: -1%; yoga: +24%), CSR left (control: worsen by 0.90 cm; yoga: improved by 4.21 cm), CSR right (control: worsen by 0.75 cm; yoga: improved by 4.28 cm), right side of BS (control: improved by 0.19 cm; yoga: improved by 4.31 cm), SLS left (control: -10%; yoga: +86%), and SLS right (control: -6%; yoga: +47%) were observed after 1-year yoga training. No significant difference was found between the two groups in insulin, HOMA indices, and disposition index. Yoga training significantly increased circulating GH (control: -3%; yoga: +22%), total circulating ghrelin (control: -26%; yoga: +13%), and UnAG (control: -27%; yoga: +14%), whereas decreased AG (control: -7%; yoga: -33%) and obestatin (control: +24%; yoga: -29%). Conclusion: One-year of yoga training modulated total ghrelin, UnAG, AG, obestatin, and GH while exerting beneficial effects on physical functions and central obesity in adults with MetS. The beneficial effects of yoga may be associated with the alteration of ghrelin gene product and GH.

3.
Article in English | MEDLINE | ID: mdl-30258404

ABSTRACT

Objective: This study aimed to investigate how central obesity and hypertension modulate unacylated ghrelin (UnAG), acylated ghrelin (AG), obestatin, growth hormone (GH), and the ratios of UnAG/obestatin, AG/obestatin, and total ghrelin/obestatin. Methods: Circulatory abundances of UnAG, AG, obestatin and GH were determined in 387 Hong Kong Chinese female adults with age between 24 to 86 years based on a 2 × 2 factorial design of hypertension (blood pressure ≥140/90 mmHg) and central obesity (waist circumference or WC ≥80 cm). Participants were categorized as neither hypertensive nor centrally obese (NHNO; n = 105), hypertensive but not centrally obese (HNO; n = 102), centrally obese but not hypertensive (NHO; n = 74) and hypertensive and centrally obese (NO; n = 106). Pearson's correlation analyses were performed to detect the association between the peptides examined with WC and blood pressure. The main and interaction effects of hypertension and central obesity were examined by generalized estimating equations analyses. Results: Correlation analyses revealed that systolic blood pressure was negatively correlated with AG/obestatin, UnAG/obestatin and total ghrelin/obestatin ratios, AG, total ghrelin, and GH, while diastolic blood pressure was negatively correlated with UnAG/obestatin, total ghrelin/obestatin ratios, and GH. WC was negatively correlated with AG/obestatin, UnAG/obestatin, and total ghrelin/obestatin ratios, UnAG, AG, total ghrelin, GH, and obestatin. Interaction effects of hypertension and central obesity were observed on UnAG/obestatin, AG/obestatin and total ghrelin/obestatin ratios, and obestatin. Obestatin in NHO group was significantly higher compared to NHNO and HO groups. UnAG/obestatin, AG/obestatin, and total ghrelin/obestatin ratios were higher in NHNO group compared to HNO and HO groups. Main effects of central obesity and hypertension were observed in UnAG, total ghrelin and GH. The HO group manifested the lowest level of UnAG, total ghrelin and GH among all the groups studied. Main effect of hypertension was observed on AG, suggesting that hypertensive individuals exhibited lower levels of AG regardless of central obesity. Conclusion: Circulatory ghrelin gene products and GH exhibit different modes of modulation in response to the co-manifestation of multiple cardiovascular risk factors compared with a single risk factor alone.

4.
BMC Bioinformatics ; 16: 182, 2015 May 31.
Article in English | MEDLINE | ID: mdl-26026612

ABSTRACT

BACKGROUND: Both differential expression (DE) and differential co-expression (DC) analyses are appreciated as useful tools in understanding gene regulation related to complex diseases. The performance of integrating DE and DC, however, remains unexplored. RESULTS: In this study, we proposed a novel analytical approach called DECODE (Differential Co-expression and Differential Expression) to integrate DC and DE analyses of gene expression data. DECODE allows one to study the combined features of DC and DE of each transcript between two conditions. By incorporating information of the dependency between DC and DE variables, two optimal thresholds for defining substantial change in expression and co-expression are systematically defined for each gene based on chi-square maximization. By using these thresholds, genes can be categorized into four groups with either high or low DC and DE characteristics. In this study, DECODE was applied to a large breast cancer microarray data set consisted of two thousand tumor samples. By identifying genes with high DE and high DC, we demonstrated that DECODE could improve the detection of some functional gene sets such as those related to immune system, metastasis, lipid and glucose metabolism. Further investigation on the identified genes and the associated functional pathways would provide an additional level of understanding of complex disease mechanism. CONCLUSIONS: By complementing the recent DC and the traditional DE analyses, DECODE is a valuable methodology for investigating biological functions of genes exhibiting disease-associated DE and DC combined characteristics, which may not be easily revealed through DC or DE approach alone. DECODE is available at the Comprehensive R Archive Network (CRAN): http://cran.r-project.org/web/packages/decode/index.html .


Subject(s)
Algorithms , Breast Neoplasms/genetics , Breast Neoplasms/metabolism , Computational Biology/methods , Gene Expression Profiling/methods , Gene Regulatory Networks , Software , Female , High-Throughput Nucleotide Sequencing/methods , Humans , Protein Interaction Maps
5.
Cancer ; 121(16): 2720-9, 2015 Aug 15.
Article in English | MEDLINE | ID: mdl-25946469

ABSTRACT

BACKGROUND: Single nucleotide polymorphism (SNP) of the excision repair cross-complementing group 1 (ERCC1) gene has been linked with sensitivity to platinum and radiation. The authors hypothesized that the ERCC1 genotype for the SNPs cytosine-to-thymine substitution at codon 118 (C118T) and cytosine-to-adenine substitution at codon 8092 (C8092A) is prognostic in patients with nasopharyngeal carcinoma (NPC) who receive either radiotherapy (RT) or cisplatin plus RT. METHODS: The authors tested their hypothesis using biomarker screening samples from the Hong Kong NPC Study Group 0502 trial, which was a prospective, multicenter clinical trial that used post-RT plasma Epstein-Bar virus (EBV) DNA (pEBV) levels to screen patients with high-risk NPC for adjuvant chemotherapy. RESULTS: ERCC1 SNPs were analyzed in 576 consecutive patients who were screened by pEBV. In the total biomarker population, there was no significant association of ERCC1 C118T or C8092A genotype with relapse-free survival (RFS) or overall survival (OS). There also was no correlation between ERCC1 genotype and ERCC1 protein or messenger RNA expression in a subset of patients who had available paired biopsies. Post-RT pEBV status was the only independent prognosticator for RFS and OS in multivariate analyses. However, there was a significant interaction between ERCC1 C118T genotype and post-RT pEBV status (RFS, P = .0106; OS, P = .0067). The ERCC1 C118T genotype was significantly associated with both RFS (hazard ratio, 1.67; 95% confidence interval, 1.07-2.61; P = .024) and OS (hazard ratio, 2.31; 95% confidence interval, 1.22-4.40; P = .0106) in the post-RT pEBV-negative population, but not in the pEBV-positive population. CONCLUSIONS: The current results prospectively validate pEBV as the most significant prognostic biomarker in NPC that can be used to select high-risk patients for adjuvant therapy. The ERCC1 C118T genotype may help to identify a favorable subgroup (approximately 7%) of pEBV-negative patients with NPC who have an excellent prognosis and can be spared the toxicities of further therapy.


Subject(s)
DNA, Viral/blood , DNA-Binding Proteins/genetics , Endonucleases/genetics , Herpesvirus 4, Human/isolation & purification , Nasopharyngeal Neoplasms/genetics , Polymorphism, Single Nucleotide , Adult , Aged , Carcinoma , Female , Genotype , Humans , Male , Middle Aged , Nasopharyngeal Carcinoma , Nasopharyngeal Neoplasms/mortality , Nasopharyngeal Neoplasms/virology , Prospective Studies
6.
Curr Gene Ther ; 15(2): 97-108, 2015.
Article in English | MEDLINE | ID: mdl-25537771

ABSTRACT

Hepatocellular carcinoma (HCC) is a complex liver disease with limited treatment options and often resulting in a poor prognosis. The development of HCC depends on the formation of new blood vessels and it demonstrates hypervascularity and invasive property to the surrounding vasculature clinically. A complex network of growth factors acting on both tumor cells and endothelial cells mediates the angiogenesis in HCC. It is an attractive approach to inhibit the angiogenic processes as the treatment of HCC and therefore, anti-angiogenic TKIs were developed to inhibit the vessel formation in the tumors. However, it is currently perceived that the efficacy of these anti-angiogenic TKIs has reached plateau, and it is necessary to develop novel agents with non-TKI mechanism to inhibit the angiogenic targets. With the better understanding of molecular mechanisms that govern angiogenesis, as well as the advancement in biomedical engineering, new approaches of gene therapy have brought hopes for therapeutic intervention in HCC. Gene therapy is based on the transfer of genetic material to the patients with the aim to modify or correct the malignancy from its molecular basis. In this article, we will discuss the conventional anti-angiogenic therapies and the gene therapy approaches in HCC. The therapeutic potential of gene therapy for HCC treatment has been demonstrated and further development of anti-angiogenic may result in new treatment option for HCC patients.


Subject(s)
Genetic Therapy , Liver Neoplasms/therapy , Neovascularization, Pathologic/therapy , Angiogenesis Inhibitors/therapeutic use , Carcinoma, Hepatocellular/genetics , Carcinoma, Hepatocellular/therapy , Humans , Liver Neoplasms/genetics , Neovascularization, Pathologic/genetics , Vascular Endothelial Growth Factor A/genetics
7.
Biosens Bioelectron ; 61: 434-42, 2014 Nov 15.
Article in English | MEDLINE | ID: mdl-24934744

ABSTRACT

We report the label-free enumeration of human colorectal-carcinoma cells from blood lymphocytes by using interdigitated ring-array microelectrodes; this enumeration was based on the dielectrophoretic selection of cells. Because of the novel design of the device, a continuous flow of cells is uniformly distributed into parallel streams through 300 rings (~40 µm in diameter each) that are integrated into the electrode digits. Using this array, 82% of cancer cells were recovered and 99% of blood lymphocytes were removed. Most of the cancer cells recovered were viable (94%) and could be cultivated for >8 days, during which period they retained their normal cell morphology and proliferation rates. The recovery rate correlated closely with cancer-cell loadings in spiked samples and this relationship was linear over a range of at least 2 orders of magnitude. Importantly, because of the 3D structure of the rings, these results were obtained at a high cell-loading concentration (10(7)cells/mL). The rings could be further optimized for use in accurate label-free identification and measurement of circulating tumor cells in cancer research and disease management.


Subject(s)
Cell Separation/instrumentation , Colorectal Neoplasms/blood , Microfluidic Analytical Techniques/instrumentation , Neoplastic Cells, Circulating/pathology , Biosensing Techniques/instrumentation , Cell Count , Cell Line, Tumor , Colorectal Neoplasms/pathology , Electrophoresis/instrumentation , Equipment Design , Humans , Lymphocytes/cytology , Microelectrodes
8.
Prenat Diagn ; 34(3): 251-8, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24352757

ABSTRACT

OBJECTIVE: Circulating placental-derived RNA is useful for noninvasive prenatal investigation. However, in addition to placental gene expression, there are limited investigations on other biological parameters that may affect the circulating placental RNA profile. In this study, we explored two of these potential parameters. METHODS: We first demonstrated the existence of such biological parameters by comparing the relative levels of a panel of placental-derived transcripts between the placentas and maternal plasma by digital PCRs. We then compared the post-delivery clearance of the transcripts by serial plasma samples collected from pregnant women after delivery. We also studied the placental in vivo localization of the transcripts by in situ hybridization. RESULTS: There was an imperfect correlation of the transcript levels between the placentas and maternal plasma, with placenta-specific 4 (PLAC4) mRNA showing the largest discrepancy. Although PLAC4 mRNA showed a similar clearance half-life with other transcripts, we observed a preferential localization of PLAC4 mRNA around the villous surface. We speculated that this phenomenon might play a role in favoring the release of PLAC4 mRNA molecules into maternal plasma. CONCLUSION: We revealed that in addition to expression levels in the placenta, other biological factors might interplay to determine the maternal plasma profile of placental-derived RNAs.


Subject(s)
Placenta/metabolism , Pregnancy/blood , RNA, Messenger/blood , Female , Humans
9.
Proc Natl Acad Sci U S A ; 110(47): 18761-8, 2013 Nov 19.
Article in English | MEDLINE | ID: mdl-24191000

ABSTRACT

We explored the detection of genome-wide hypomethylation in plasma using shotgun massively parallel bisulfite sequencing as a marker for cancer. Tumor-associated copy number aberrations (CNAs) could also be observed from the bisulfite DNA sequencing data. Hypomethylation and CNAs were detected in the plasma DNA of patients with hepatocellular carcinoma, breast cancer, lung cancer, nasopharyngeal cancer, smooth muscle sarcoma, and neuroendocrine tumor. For the detection of nonmetastatic cancer cases, plasma hypomethylation gave a sensitivity and specificity of 74% and 94%, respectively, when a mean of 93 million reads per case were obtained. Reducing the sequencing depth to 10 million reads per case was found to have no adverse effect on the sensitivity and specificity for cancer detection, giving respective figures of 68% and 94%. This characteristic thus indicates that analysis of plasma hypomethylation by this sequencing-based method may be a relatively cost-effective approach for cancer detection. We also demonstrated that plasma hypomethylation had utility for monitoring hepatocellular carcinoma patients following tumor resection and for detecting residual disease. Plasma hypomethylation can be combined with plasma CNA analysis for further enhancement of the detection sensitivity or specificity using different diagnostic algorithms. Using the detection of at least one type of aberration to define an abnormality, a sensitivity of 87% could be achieved with a specificity of 88%. These developments have thus expanded the applications of plasma DNA analysis for cancer detection and monitoring.


Subject(s)
DNA Copy Number Variations/genetics , DNA Methylation/genetics , Genome, Human/genetics , High-Throughput Nucleotide Sequencing/methods , Neoplasms/genetics , Sequence Analysis, DNA/methods , Epigenomics/methods , Gene Library , Hong Kong , Humans , Plasma/chemistry
10.
Cancer ; 118(16): 3984-92, 2012 Aug 15.
Article in English | MEDLINE | ID: mdl-22180222

ABSTRACT

BACKGROUND: The level of circulating interleukin 10 (IL-10) is elevated in a proportion of patients with hepatocellular carcinoma (HCC). The objective of the current study was to evaluate the prognostic significance of serum the IL-10 level in patients with unresectable HCC. METHODS: Patients with unresectable HCC who provided serum at the time of diagnosis were enrolled prospectively in the study. The level of circulating IL-10 in serum samples was determined by enzyme-linked immunosorbent assay. The association of the IL-10 level with overall survival was evaluated in relation to sociodemographics, liver function, hepatitis B viral load, and tumor staging. RESULTS: In total, 222 patients were recruited; of these, 82.4% were positive for hepatitis B virus surface antigen, and 65.8% had Barcelona Clinic Liver Cancer stage C disease. The mean log IL-10 level was 1.1 pg/mL, and 146 patients had an IL-10 level >1 pg/mL (high IL-10 group). The high IL-10 group had worse overall survival than the low IL-10 group (5.0 months vs 14.9 months; hazard ratio, 2.192; P < .0001). The IL-10 level was associated with worse hepatic function and with a high alanine transaminase (ALT) level. The IL-10 level remained an independent prognostic factor (hazard ratio, 1.824; P = .0005) after adjustment for sociodemographics, tumor staging, treatment, Child-Pugh stage, and ALT level. The IL-10 level also subdivided patients into 2 populations with distinct survival (10.2 months vs 3.5 months; P = .0027). CONCLUSIONS: The serum IL-10 level was identified as an independent prognostic factor for unresectable HCC. The current findings suggested that an elevated IL-10 level may be related to hepatic injury caused by cirrhotic processes rather than tumor load. The authors concluded that the IL-10 level offers additional prognostic value to the existing tumor staging systems.


Subject(s)
Carcinoma, Hepatocellular/blood , Interleukin-10/blood , Liver Neoplasms/blood , Adult , Aged , Carcinoma, Hepatocellular/pathology , Female , Hepatitis B/complications , Humans , Liver Neoplasms/pathology , Male , Neoplasm Staging , Prognosis
11.
Invest New Drugs ; 29(6): 1123-31, 2011 Dec.
Article in English | MEDLINE | ID: mdl-20467883

ABSTRACT

PURPOSE: Sunitinib is a multi-target receptor tyrosine kinase (RTK) inhibitor against vascular endothelial growth factor receptors, platelet-derived growth factor receptors (PDGFR), c-kit and RET. Several of these RTKs are known to be involved in the progression of nasopharyngeal carcinoma (NPC). Here, we evaluated the preclinical activities of sunitinib in NPC. METHOD: We determined the basal level of total and phosphorylated PDGFR, c-kit and RET by immunoblotting in a panel of five NPC cell lines. The effect of sunitinib on NPC cell proliferation was evaluated by MTT assay. We further studied the effect of sunitinib on NPC cell cycle progression and apoptosis. We investigated the in vitro and in vivo activities of sunitinib as single agent and in combination with cisplatin or docetaxel in NPC cell lines and tumor xenografts. RESULTS: Sunitinib exhibited dose-dependent growth inhibition in all NPC cell lines tested with IC(50) between 2-7.5 µM and maximum inhibition of over 97%. Sunitinib induced apoptosis and cell cycle arrest at G(0)/G(1) phase. In vitro, sunitinib moderately enhanced the growth inhibition of cisplatin or docetaxel. Single agent sunitinib demonstrated significant growth inhibition, reduced microvessel density and caused extensive tumor necrosis in a NPC xenograft model. However, concurrent administration of sunitinib and docetaxel induced severe toxicity in mice without enhanced antitumor effect. CONCLUSIONS: Single agent sunitinib demonstrated potent in vitro and in vivo growth inhibition in NPC. When combined with chemotherapy, sequential instead of concurrent administration schedule should be further explored.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/pharmacology , Indoles/pharmacology , Nasopharyngeal Neoplasms/drug therapy , Protein Kinase Inhibitors/pharmacology , Pyrroles/pharmacology , Animals , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Apoptosis/drug effects , Cell Cycle/drug effects , Cell Line, Tumor , Cell Proliferation/drug effects , Cisplatin/administration & dosage , Docetaxel , Dose-Response Relationship, Drug , Female , Humans , Indoles/administration & dosage , Mice , Mice, Nude , Nasopharyngeal Neoplasms/pathology , Protein Kinase Inhibitors/administration & dosage , Protein Kinase Inhibitors/toxicity , Pyrroles/administration & dosage , Sunitinib , Taxoids/administration & dosage , Xenograft Model Antitumor Assays
12.
Clin Chem ; 55(4): 715-22, 2009 Apr.
Article in English | MEDLINE | ID: mdl-18974360

ABSTRACT

BACKGROUND: The term "transrenal DNA" was coined in 2000 to signify that DNA in urine may come from the passage of plasma DNA through the kidney barrier. Although DNA in the urine has the potential to provide a completely noninvasive source of nucleic acids for molecular diagnosis, its existence remains controversial. METHODS: We obtained blood and urine samples from 22 hematopoietic stem cell transplant (HSCT) recipients and used fluorescence in situ hybridization, PCR for short tandem repeats, mass spectrometry, quantitative PCR, and immunofluorescence detection to study donor-derived DNA in the urine. RESULTS: All HSCT recipients exhibited high amounts of donor-derived DNA in buffy coat and plasma samples. Male donor-derived DNA was detected in supernatants of urine samples from all 5 female sex-mismatched HSCT recipients. Surprisingly, the amount of DNA in urine supernatants was not correlated with the plasma value. Moreover, cell-free urine supernatants contained DNA fragments >350 bp that were absent in plasma. Donor-derived polymorphs were detected in urine by fluorescence in situ hybridization. Coincidentally, donor-derived cytokeratin-producing epithelial cells were discovered in urine samples from 3 of 10 sex-mismatched HSCT recipients as long as 14.2 years after transplantation. CONCLUSIONS: This report is the first to demonstrate the presence of donor-derived DNA in the urine of HSCT recipients; however, we show that much of this DNA originates from donor-derived cells, rather than from the transrenal passage of cell-free plasma DNA. Our discovery of donor-derived cytokeratin-producing epithelial cells raises interesting biological and therapeutic implications, e.g., the capacity of marrow stem cells to serve as an extrarenal source for renal tubule regeneration.


Subject(s)
DNA/urine , Hematopoietic Stem Cell Transplantation , Kidney/physiology , Models, Biological , Tissue Donors , DNA/blood , DNA/genetics , Epithelial Cells/metabolism , Female , Humans , Male , Transplantation, Homologous
13.
Clin Cancer Res ; 14(21): 7080-7, 2008 Nov 01.
Article in English | MEDLINE | ID: mdl-18981006

ABSTRACT

PURPOSE: Recent studies have suggested that osteopontin is induced by hypoxia in head and neck cancer cell lines and its plasma level may serve as a surrogate marker for tumor hypoxia and treatment outcome in head and neck cancer. We investigated the response of osteopontin to in vitro hypoxia in nasopharyngeal carcinoma cell lines, and determined plasma osteopontin levels in nasopharyngeal carcinoma patients, nonnasopharyngeal carcinoma head and neck cancer patients, and healthy controls. We explored the relationship of plasma osteopontin and response to radiotherapy in nasopharyngeal carcinoma. EXPERIMENTAL DESIGN: Nasopharyngeal carcinoma cell lines HK1, HONE-1, C666-1, and CNE-2 were treated with 0 to 48 hours of hypoxia or normoxia, +/- reoxygenation. Osteopontin secretion in the supernatant was measured by ELISA assay. Cellular osteopontin protein and mRNA were detected by Western blotting and reverse transcription-PCR, respectively. Plasma osteopontin levels in patients (n=66; 44 nasopharyngeal carcinoma, 22 head and neck cancer) and controls (n=29) were measured by ELISA. RESULTS: Hypoxia has no effect on osteopontin protein and mRNA level in nasopharyngeal carcinoma cells. Only CNE-2 secreted osteopontin, and there was no significant induction by hypoxia. Plasma osteopontin levels in patients of metastatic nasopharyngeal carcinoma and head and neck cancer, but not in locoregional nasopharyngeal carcinoma, were significantly higher than in controls. In patients with locoregional nasopharyngeal carcinoma receiving curative radiotherapy (n=31), a high (>median) pretreatment plasma osteopontin level was a significant predictor of poor response to radiotherapy (complete response rate, 40% versus 88%; P=0.009), which remained significant in multivariate analysis. CONCLUSION: Our results suggested that the pretreatment plasma osteopontin level may be a useful biomarker of response to radiotherapy in nasopharyngeal carcinoma.


Subject(s)
Carcinoma/blood , Carcinoma/radiotherapy , Cell Hypoxia , Nasopharyngeal Neoplasms/blood , Nasopharyngeal Neoplasms/radiotherapy , Osteopontin/blood , Adult , Aged , Biomarkers, Tumor/analysis , Carcinoma/pathology , Cell Line, Tumor , Female , Humans , Male , Middle Aged , Nasopharyngeal Neoplasms/pathology , Treatment Outcome
14.
Am J Pathol ; 170(3): 941-50, 2007 Mar.
Article in English | MEDLINE | ID: mdl-17322379

ABSTRACT

The pseudomalignant nature of the placenta prompted us to search for tumor suppressor gene hypermethylation, a phenomenon widely reported in cancer, in the human placenta. Nine tumor suppressor genes were studied. Hypermethylation of the Ras association domain family 1 A (RASSF1A) gene was found in human placentas from all three trimesters of pregnancy but was absent in other fetal tissues. Hypermethylation of Rassf1 was similarly observed in placentas from the rhesus monkey but not the mouse. An inverse relationship between RASSF1A promoter methylation and gene expression was demonstrated by bisulfite sequencing of microdissected placental cells and immunohistochemical staining of placental tissue sections using an anti-RASSF1A antibody. Treatment of choriocarcinoma cell lines, JAR and JEG3, by 5-aza-2'-deoxycytidine and trichostatin A led to reduction in RASSF1A methylation but increased expression. These observations extend the analogy between the primate placenta and malignant tumors to the epigenetic level.


Subject(s)
DNA Methylation , Epigenesis, Genetic , Placenta/physiology , Tumor Suppressor Proteins/genetics , Amino Acid Sequence , Animals , Biomarkers, Tumor/analysis , Biomarkers, Tumor/genetics , Cell Line, Tumor , DNA Primers , Female , Gene Expression , Genes, Tumor Suppressor , Humans , Immunohistochemistry , Lasers , Macaca mulatta , Mice , Microdissection , Molecular Sequence Data , Pregnancy , Promoter Regions, Genetic , Reverse Transcriptase Polymerase Chain Reaction , Sequence Homology, Amino Acid
15.
Am J Surg Pathol ; 28(6): 801-7, 2004 Jun.
Article in English | MEDLINE | ID: mdl-15166673

ABSTRACT

Rabbit monoclonal antibody (MAb), which has become available only recently, theoretically combines the advantage of the high affinity attributable to its rabbit origin and the high specificity due to its monoclonal nature. Since immunohistochemical demonstration of cyclin D1 is notoriously difficult, this study aims to assess whether a newly available rabbit MAb against cyclin D1 (SP4) can improve the consistency of immunostaining, especially for the diagnosis of mantle cell lymphoma (MCL). A total of 150 cases of lymphoproliferative lesions, including 30 cases of MCL, histologic mimickers of MCL, and various types of lymphomas and leukemias, were studied. Immunostaining was performed on formalin-fixed, paraffin-embedded tissue sections using a labeled streptavidin-biotin peroxidase system in an automated immunostainer. All cases of MCL expressed cyclin D1, with a higher median staining score (8 out of a maximum of 12) compared with mouse MAb DCS-6 (score 4). In addition, 2 of 15 cases of B-cell chronic lymphocytic leukemia (B-CLL), 3 of 12 cases of multiple myeloma, and 2 of 5 cases of hairy cell leukemia were also positive. Comparable staining results could also be achieved by an optimized manual staining protocol. This study thus confirms the superior performance of the rabbit MAb SP4, which should permit consistent immunostaining for cyclin D1 to be readily achieved. The value of cyclin D1 immunohistochemistry in the differential diagnosis of MCL from other low-grade B-cell lymphomas is also affirmed, but with the caveat that rare cases of B-CLL can also be cyclin D1 positive.


Subject(s)
Antibodies, Monoclonal/pharmacology , Cyclin D1/immunology , Immunohistochemistry/methods , Staining and Labeling/methods , Animals , Biotin , Cyclin D1/analysis , Diagnosis, Differential , Humans , Leukemia, Hairy Cell/pathology , Leukemia, Lymphocytic, Chronic, B-Cell/pathology , Lymphoma, Mantle-Cell/pathology , Rabbits , Streptavidin
16.
Am J Clin Pathol ; 121(3): 335-42, 2004 Mar.
Article in English | MEDLINE | ID: mdl-15023037

ABSTRACT

We assessed the usefulness of a mouse monoclonal antibody (13B10) against human herpesvirus 8 (HHV-8) latent nuclear antigen-1 (LNA-1) in diagnosis of Kaposi sarcoma (KS) and for distinguishing it from various mimickers by studying 50 cases of KS and 53 mimickers (angiosarcoma, 15; kaposiform hemangioendothelioma, 6; spindle cell hemangioma, 3; reactive angioendotheliomatosis, 3; bacillary angiomatosis, 4; acroangiomatous dematitis, 2; microvenular hemangioma, 2; hobnail hemangioma, 2; pyogenic granuloma, 5; dermatofibroma, 8; arteriovenous hemangioma, 1; verrucous hemangioma, 1; nonspecific vascular proliferation, 1) from patients with or without acquired HIV infection. Immunohistochemical staining was performed on formalin-fixed, paraffin-embedded tissue sections. All 50 cases of KS were positive for HHV-8 LNA-1, with immunolocalization in the nuclei of the spindle cells and cells lining the primitive and thin-walled vascular channels, whereas all 53 mimickers (including 4 lesions from HIV-positive patients) tested negative. The results idicate that positive immunostaining for HHV-8 LNA- 1 exhibits high sensitivity and specificity for the diagnosis of KS and is, thus, useful for distinguishing it from the mimickers.


Subject(s)
Herpesvirus 8, Human/isolation & purification , Nuclear Proteins/biosynthesis , Phosphoproteins/biosynthesis , Sarcoma, Kaposi/diagnosis , Adult , Antibodies, Monoclonal , Diagnosis, Differential , Humans , Immunohistochemistry , Male , Nuclear Proteins/immunology , Phosphoproteins/immunology , Sarcoma, Kaposi/virology , Sensitivity and Specificity , Skin Diseases/diagnosis
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