Epicardial adipose tissue as a source of nuclear factor-kappaB and c-Jun N-terminal kinase mediated inflammation in patients with coronary artery disease

CONTEXT

Visceral adipose tissue (AT) is known to confer a significantly higher risk of type 2 diabetes and cardiovascular disease. Epicardial AT has been shown to be related to cardiovascular disease and myocardial function through unidentified mechanisms. Epicardial AT expresses an inflammatory profile of proteins; however, the mechanisms responsible are yet to be elucidated.

OBJECTIVES

The objectives of the study were to: 1) examine key mediators of the nuclear factor-kappaB (NFkappaB) and c-Jun N-terminal kinase (JNK) pathways in paired epicardial and gluteofemoral (thigh) AT from coronary artery disease (CAD) and control patients and 2) investigate circulating endotoxin levels in CAD and control subjects.

DESIGN

Serums and AT biopsies (epicardial and thigh) were obtained from CAD (n = 16) and non-CAD (n = 18) patients. Inflammation was assessed in tissue and serum samples through Western blot, real-time PCR, ELISAs, and activity studies.

RESULTS

Western blotting showed epicardial AT had significantly higher NFkappaB, inhibitory-kappaB kinase (IKK)-gamma, IKKbeta, and JNK-1 and -2 compared with thigh AT. Epicardial mRNA data showed strong correlations between CD-68 and toll-like receptor-2, toll-like receptor-4, and TNF-alpha. Circulating endotoxin was elevated in patients with CAD compared with matched controls [CAD: 6.80 +/- 0.28 endotoxin unit(EU)/ml vs. controls: 5.52 +/- 0.57 EU/ml; P<0.05].

CONCLUSION

Epicardial AT from patients with CAD shows increased NFkappaB, IKKbeta, and JNK expression compared with both CAD thigh AT and non-CAD epicardial AT, suggesting a depot-specific as well as a disease-linked response to inflammation. These studies implicate both NFkappaB and JNK pathways in the inflammatory profile of epicardial AT and highlight the role of the macrophage in the inflammation within this tissue.

LHX6 is a sensitive methylation marker in head and neck carcinomas

Head and neck cancer remains a morbid and often fatal disease and at the present time few effective molecular markers have been identified. The purpose of the present work was to identify new molecular markers for head and neck squamous cell carcinoma (HNSCC). We applied methylation-sensitive arbitrarily primed PCR (MS/AP-PCR) to isolate sequences differentially methylated in HNSCC. The most frequently hypermethylated fragment we found maps close to a cytosine guanine dinucleotide (CpG) island on chromosome 9q33.2, and hypermethylation of this CpG island was associated with transcriptional silencing of an alternative transcript of the LHX6 gene. Using combined bisulfite restriction analysis (COBRA), hypermethylation of this fragment was detected in 13 of 14 (92.8%) HNSCC cell lines studied and 21 of 32 (65.6%) primary tumors, whereas little or no methylation was seen in 10 normal oral mucosa samples. We extended this investigation to other cancer cell lines and methylation was found in those derived from colon, breast, leukemia and lung, and methylation was also found in 12/14 primary colon tumors. These findings suggest that differentially methylated (DIME)-6 hypermethylation is a good cancer marker in HNSCC as well as in other kinds of neoplasias and confirm the importance of searching for markers of epigenetic dysregulation in cancer.

Human BAC contig covering the deleted region in pancreatic cancer at 12q21

In sporadic human primary pancreatic cancer tissues, loss of heterozygosity is frequently observed in the 1-cM region between D12S81 and D12S1719 at 12q21. Loss of this chromosome arm is known to be associate with a poor prognosis in pancreatic cancer patients. Herein we report a complete contig of human bacterial artificial chromosome (BAC) clones covering the deleted region. The region was covered by 21 BAC clones in a minimum tiling path. The clones were confirmed to exist at 12q21 by fluorescence in situ hybridization. We identified novel 40 sequence tagged sites and mapped 10 expressed sequence tags in this region. The BAC contig reported here provides an avenue for determining the complete nucleotide sequence and mining putative tumor suppressor genes in the deleted region of pancreatic cancer at 12q21.

Diminished expression of S100A2, a putative tumor suppressor, at early stage of human lung carcinogenesis

To identify and understand early events in lung carcinogenesis, we used a cDNA array to screen for genes that are expressed differentially in normal human bronchial epithelial (NHBE) cells and a tumorigenic cell line (1170-I) derived from immortalized HBE cells after exposure to cigarette smoke condensate in vivo. Among these genes, we have identified the S100A2 gene, which encodes a nuclear calcium-binding protein, as being down-regulated in the 1170-I cells. Because this gene has been implicated as a tumor suppressor in breast cancer, we examined its potential role as a tumor suppressor in lung carcinogenesis. Levels of S100A2 transcript and protein, which were high in NHBE cells, decreased by up to 50% in immortalized HBE cells (BEAS-2B and 1799) and to low to nearly undetectable levels in transformed (1198) and tumorigenic (1170-I) HBE cells. Furthermore, S100A2 mRNA and protein were undetectable in 8 and expressed at a reduced level in 3 of 11 non-small cell lung cancer (NSCLC) cell lines. Positive immunohistochemical staining of S100A2 was detected in the majority (75-83%) of normal and hyperplastic lung tissues, whereas it was detected in <10% of metaplastic lung tissues, squamous cell carcinoma, and adenocarcinoma. Treatment of 1170-I HBE and NSCLC cells with 5-aza-2'-deoxycytidine resulted in partial restoration of S100A2 expression in seven of eight cell lines. Indeed, CpG methylation was detected in the promoter region of the S100A2 gene. Our results suggest that S100A2 expression is suppressed early during lung carcinogenesis, possibly by hypermethylation of its promoter, and that its loss may be a contributing factor in lung cancer development or a biomarker of early changes in this process.

Differential effects of chromosome 3p deletion on the expression of the putative tumor suppressor RAR beta and on retinoid resistance in human squamous carcinoma cells

Retinoids' effects on cell growth and differentiation are mediated by nuclear retinoid receptors, which are ligand-activated transcription enhancing factors. Because the expression of the retinoic acid receptor beta (RARbeta) gene, which is located on chromosome 3p24, is diminished in premalignant and malignant tissues it has been proposed that it acts as a tumor suppressor. To test the hypothesis that RARbeta loss leads to retinoid resistance, we studied several karyotyped head and neck squamous carcinoma (HNSCC) cell lines (UMSCC-17A, -17B, -22A, -22B, and -38) with deletion of one chromosome 3p arm. RARbeta mRNA was neither detected nor induced by retinoic acid in these cells, whereas it was expressed and induced by retinoic acid in two other HNSCC cell lines (1483 and 183) without 3p deletion. Methylation of the RARbeta gene promoter was detected in the 17B and 22B cells that failed to express RARbeta but no methylation was found in 183A cells that did express RARbeta mRNA. Responsiveness of HNSCC cells to several retinoids in assays of growth inhibition and colony formation, was rank ordered as: 22B>1483>38>183>17B. Additionally, retinoid response elements were transactivated in 22B more efficiently than in 17B cells. These results indicate that loss of RARbeta expression does not necessarily lead to loss of growth inhibition by retinoids or to a block of retinoid signaling.

Evidence supporting a role for mitochondrial respiration in apoptosis induction by the synthetic retinoid CD437

Retinoids have been shown to modulate cell proliferation, differentiation, and apoptosis. It is thought that these effects mediate the chemopreventive and therapeutic effects of retinoids. Recently, some synthetic retinoids, including 6-[3-(1-adamantyl)-4-hydroxyphenyl]-2-naphthalene carboxylic acid (CD437), have been found to induce apoptosis even in tumor cell lines that are resistant to all-trans retinoic acid. The proapoptotic activity of CD437 has been attributed to mitochondrial dysfunction via the induction of mitochondrial permeability transition (P. Marchetti et al., Cancer Res. 59: 6257-6266, 1999). The mechanistic aspects pertaining to how CD437 promotes changes in mitochondrial function are unclear. This study investigated the role of mitochondrial respiration in CD437-induced apoptosis. Human cutaneous squamous cell carcinoma COLO 16 cells were chronically exposed to ethidium bromide to inhibit mitochondrial DNA synthesis and produce respiration-deficient clones. These clones were exposed to CD437 (<or=10 microM) for 48 h and exhibited a marked resistance to mitochondrial permeability transition and apoptosis illustrating that mitochondrial respiration was required for these effects.

Genomic analysis of DUSP6, a dual specificity MAP kinase phosphatase, in pancreatic cancer

DUSP6 (alias PYST1), one of the dual-specificity tyrosine phosphatases, is localized on 12q21, one of the regions of frequent allelic loss in pancreatic cancer. This gene is composed of three exons, and two forms of alternatively spliced transcripts are ubiquitously expressed. Although no mutations were observed in 26 pancreatic cancer cell lines, reduced expressions of the full-length transcripts were observed in some cell lines, which may suggest some role for DUSP6 in pancreatic carcinogenesis.

An autopsy case of ovarian hyperstimulation syndrome with massive pulmonary edema and pleural effusion

Ovarian hyperstimulation syndrome (OHSS) is the most serious complication of ovulation induction with exogenous gonadotropins, such as human menopausal gonadotropin and follicle-stimulating hormone. These hormones are considered to increase capillary permeability and cause third space fluid shift. We report an autopsy case of severe OHSS in a 28-year-old Japanese female. The patient developed bilateral chest pain and progressive dyspnea during the course of administration of human gonadotropins. Pleural effusion and hypouresis clinically disappeared 4 days after the onset of the symptoms, but the patient died suddenly of rapid respiratory insufficiency. Autopsy examination revealed massive pulmonary edema, intra-alveolar hemorrhage and pleural effusion without any evidence of pulmonary thromboembolism. Histopathological examination of the ovary demonstrated multiple well-developed follicle formations, consistent with OHSS. It is very important to recognize that massive pulmonary edema can occur in a patient with OHSS. To the best of our knowledge, this is the first autopsy report of a patient with severe OHSS.

Cloning and characterization of the human UDP-N-acetylglucosamine: alpha-1,3-D-mannoside beta-1,4-N-acetylglucosaminyltransferase IV-homologue (hGnT-IV-H) gene

A novel human gene determining a polypeptide product of 478 residues with an estimated molecular mass of 55 kDa, which has significant homology and structural similarity to Bos UDP-N-acetylglucosamine: alpha-1,3-D-mannoside beta-1,4-N-acetylglucosaminyltransferase (GnT-IV), was cloned from the commonly deleted region in pancreatic cancer at 12q21. The gene is composed of at least six exons, and the last three exons cover the open reading frame. Different sized transcripts, 3.8-kb in the heart, brain, and fetal brain and 2.8-kb and 1.7-kb in the testis were observed by Northern blot analysis. By reverse transcription-polymerase chain reaction, expression was also observed in the adult brain, liver, and adrenal gland, but not in pancreas. Because of its significant homology and structural similarity to Bos GnT-IV, it is potentially the gene encoding human GnT-IV or its homologue, which had been one of two genes remaining to be cloned in the human GnT family.

Elevation of urinary enzyme levels in rat bladder carcinogenesis

Urinary enzyme levels were investigated in rats administered different promoters in their diet for 32 weeks after being initiated by treatment with 0.05% N-butyl-N-(4-hydroxybutyl)nitrosamine in their drinking water for 4 weeks. All groups were composed of 10 rats each. Group 1: females treated with 3% uracil (100% carcinoma incidence). Group 2: control females kept on basal diet only (0% carcinoma incidence). Group 3: males treated with 5% sodium L-ascorbate (100% carcinoma incidence). Group 4: control males (0% carcinoma incidence). Urine was collected at the end of weeks 12, 24 and 36 and tested for lactate dehydrogenase (LDH), alkaline phosphatase, N-acetyl-beta-D-glucosaminase and aspartate aminotransferase activity. To facilitate comparison, data were related to the corresponding excreted creatinine levels. All measurements were made using a centrifugal automatic analyzer. The urine of rats with cancer lesions (groups 1 and 3) showed significant elevation in all enzyme activities at weeks 24 and/or 36 except for LDH in females (group 1). The M/H ratio of the LDH isozymes was reversed (1.10 +/- 0.10) in the tested rats with carcinomas at week 36. This study thus provides evidence of a correlation between high urinary enzyme levels and cancer development in the rat bladder. Measurement of the tested enzymes might thus provide a method to detect malignant changes in bladder epithelium by direct urine analysis.

Identification of two common regions of allelic loss in chromosome arm 12q in human pancreatic cancer

Using the method of microsatellite analysis, we studied 40 tissues with pancreatic ductal adenocarcinoma and identified two commonly deleted regions on the long arm of chromosome 12. One (region A) was found between D12S81 and D12S1719 at 12q21 at a frequency of 67.5%, and the other (region B) was located between D12S360 and D12S78 at 12q22-q23.1 at a frequency of 60%; the latter was reported previously (M. Kimura, et al. Genes Chromosomes Cancer, 17: 88-93, 1996). The results of microsatellite analyses were verified by fluorescence in situ hybridization. We further analyzed 19 pancreatic cancer cell lines by fluorescence in situ hybridization and found that 10 of them showed allelic loss at D12S81 and 6 showed allelic loss at D12S360. Yeast artificial chromosome contigs were constructed to cover the deleted regions. Region B was completely covered by a 650-kb yeast artificial chromosome clone. The frequently deleted regions in chromosome 12q in pancreatic cancer that were identified here may provide new avenues for isolating novel tumor suppressor genes.

Overexpression of cyclin D1 in rat esophageal carcinogenesis model

Overexpression of cyclin D1 in human esophageal carcinomas has been well documented. The aim of the present study was to assess the expression of cyclin D1 in different types of esophageal epithelial lesions induced by N-nitrosomethylbenzylamine (NMBA) in rats. A total of 30 rats received s.c.-injections, five times/week, of 1.0 mg/kg NMBA for a period of 5 weeks followed by the same dose once per week for another 10 weeks. An additional 15 rats were given saline and used as controls to provide normal epithelium. The tumor incidence was 100% at the termination point of 21 weeks. Seventeen rats (57%) showed nuclear staining for cyclin D1, with a great variation in the intensity, as demonstrated by using an immunohistochemical technique. The cyclin D1 positive indices were in the range of 0% to 60% of the individual cells. Negligible staining was observed for normal esophageal epithelium, with a minimal increase in hyperplastic and dysplastic lesions. A significant elevation of cyclin D1 levels was observed in tumors. However, no significant differences were found between papillomas and carcinomas. The immunohistochemical results were confirmed by western blotting analysis. Tumors, papillomas and carcinomas overexpressing cyclin D1 had elevated proliferating cell nuclear antigen (PCNA) indices (P < 0.05). The correlation coefficient of overexpressions of PCNA and cyclin D1 was r = 0.7 for papillomas, but only r=0.3 for carcinomas. The study thus provides strong evidence of relatively early overexpression of cyclin D1 during tumorigenesis in the present rat esophageal model. Cyclin D1 expression is not simply a direct consequence of increase cell proliferation.

Prognostic significance of the MIB-1 proliferation index for patients with squamous cell carcinoma of the esophagus

BACKGROUND

A number of studies have indicated that the ki-67 proliferation index is of important prognostic significance for a variety of neoplasias. It was the aim of this study to investigate whether any correlation exits between the MIB-1 proliferation index and various clinicopathologic parameters in squamous cell carcinomas of the esophagus from 72 patients (20 women: median age, 64 years; range, 45-79 years; and 52 men: median age, 61 years; range, 43-77 years).

METHODS

Proliferative activity was determined using an immunohistochemical method with monoclonal antibody MIB-1 (ABC method), for tumor samples obtained from individuals who underwent esophagectomy in the period from 1983 to 1991. The percentage proliferation index (PI) was calculated as the number of positive cells divided by the total number of cells examined. Thirty-nine patients (54%) died of recurrence of esophageal cancer, with a median survival span of 15 months (range, 1-58 months). Thirty-three patients (46%) were still alive at the time of this study; their median follow up was 57 months (range, 40-98 months).

RESULTS

Significant differences between proliferative index values were recorded for the following parameters: survival rate, P < 0.0001; presence of lymph node metastasis, P < 0.05; size of the primary esophageal lesion, P < 0.01; proliferation pattern of the tumor, P < 0.01; and age of the patients, P < 0.05. No correlation was found regarding histologic differentiation, clinical stage, location of the lesion, intraepithelial cancerous spread, lymphatic and blood vessel invasion, and sex of the patients.

CONCLUSION

The MIB-1 proliferation index may be a powerful prognostic marker for patients with squamous cell carcinomas of the esophagus.

Prognostic significance of the MIB-1 proliferation index for patients with squamous cell carcinoma of the esophagus

BACKGROUND

A number of studies have indicated that the ki-67 proliferation index is of important prognostic significance for a variety of neoplasias. It was the aim of this study to investigate whether any correlation exits between the MIB-1 proliferation index and various clinicopathologic parameters in squamous cell carcinomas of the esophagus from 72 patients (20 women: median age, 64 years; range, 45-79 years; and 52 men: median age, 61 years; range, 43-77 years).

METHODS

Proliferative activity was determined using an immunohistochemical method with monoclonal antibody MIB-1 (ABC method), for tumor samples obtained from individuals who underwent esophagectomy in the period from 1983 to 1991. The percentage proliferation index (PI) was calculated as the number of positive cells divided by the total number of cells examined. Thirty-nine patients (54%) died of recurrence of esophageal cancer, with a median survival span of 15 months (range, 1-58 months). Thirty-three patients (46%) were still alive at the time of this study; their median follow up was 57 months (range, 40-98 months).

RESULTS

Significant differences between proliferative index values were recorded for the following parameters: survival rate, P < 0.0001; presence of lymph node metastasis, P < 0.05; size of the primary esophageal lesion, P < 0.01; proliferation pattern of the tumor, P < 0.01; and age of the patients, P < 0.05. No correlation was found regarding histologic differentiation, clinical stage, location of the lesion, intraepithelial cancerous spread, lymphatic and blood vessel invasion, and sex of the patients.

CONCLUSION

The MIB-1 proliferation index may be a powerful prognostic marker for patients with squamous cell carcinomas of the esophagus.