COPD as a Disease of Immunosenescence

Although chronic obstructive pulmonary disease (COPD) is regarded as a chronic inflammatory lung disease, the disease mechanism is still not known. Intriguingly, aging lungs are quite similar to COPD-affected lungs in many ways, and COPD has been viewed as a disease of accelerated premature aging of the lungs. In this paper, based on a literature review, we would like to propose immunosenescence, age-associated decline in immunity, as a critical mechanism for the development of COPD. Immunosenescence can cause a low-grade, systemic inflammation described as inflammaging. This inflammaging may be directly involved in the COPD pathogenesis. The potential contributors to the development of inflammaging in the lungs possibly leading to COPD are discussed in the review paper. A notable fact about COPD is that only 15% to 20% of smokers develop clinically significant COPD. Given that there is a substantial inter-individual variation in inflammaging susceptibility, which is genetically determined and significantly affected by the history of the individual's exposure to pathogens, immunosenescence and inflammaging may also provide the answer for this unexpectedly low susceptibility of smokers to clinically significant COPD.

Chitotriosidase in the Pathogenesis of Inflammation, Interstitial Lung Diseases and COPD

As a member of 18 glycosyl hydrolase (GH) family, chitotriosidase (Chitinase 1, CHIT1) is a true chitinase mainly expressed in the differentiated and polarized macrophages. CHIT1 is an innate immune mediator that digests the cell walls of chitin-containing eukaryotic pathogens, such as fungi. However, CHIT1 is dysregulated in granulomatous and fibrotic interstitial lung diseases characterized by inflammation and tissue remodeling. These include tuberclosis, sarcoidosis, idiopathic pulmonary fibrosis, scleroderma-associated interstitial lung diseases (SSc-ILD), and chronic obstructive lung diseases (COPD). CHIT1 serum concentration correlates with the progression or the severity of these diseases, suggesting a potential use of CHIT1 as a biomarker or a therapeutic target. Recent studies with genetically modified mice demonstrate that CHIT1 enhances TGF-beta1 receptor expression and signaling, suggesting a role in initiating or amplifying the response to organ injury and repair. This additional CHIT1 activity is independent of its enzymatic activity. These studies suggest that CHIT1 serves a bridging function; it is both an innate immune mediator and a regulator of tissue remodeling. This review will focus on recent data linking CHIT1 to the pathogenesis of inflammation, interstitial lung disease, and COPD.

Modifiers of TGF-beta1 effector function as novel therapeutic targets of pulmonary fibrosis

Pulmonary fibrosis is a fatal progressive disease with no effective therapy. Transforming growth factor (TGF)-beta1 has long been regarded as a central mediator of tissue fibrosis that involves multiple organs including skin, liver, kidney, and lung. Thus, TGF-beta1 and its signaling pathways have been attractive therapeutic targets for the development of antifibrotic drugs. However, the essential biological functions of TGF-beta1 in maintaining normal immune and cellular homeostasis significantly limit the effectiveness of TGF-beta1-directed therapeutic approaches. Thus, targeting downstream mediators or signaling molecules of TGF-beta1 could be an alternative approach that selectively inhibits TGF-beta1-stimulated fibrotic tissue response while preserving major physiological function of TGF-beta1. Recent studies from our laboratory revealed that TGF-beta1 crosstalk with epidermal growth factor receptor (EGFR) signaling by induction of amphiregulin, a ligand of EGFR, plays a critical role in the development or progression of pulmonary fibrosis. In addition, chitotriosidase, a true chitinase in humans, has been identified to have modulating capacity of TGF-beta1 signaling as a new biomarker and therapeutic target of scleroderma-associated pulmonary fibrosis. These newly identified modifiers of TGF-beta1 effector function significantly enhance the effectiveness and flexibility in targeting pulmonary fibrosis in which TGF-beta1 plays a significant role.

Protective effects of basic fibroblast growth factor in the development of emphysema induced by interferon-gamma

Recent clinical evidence indicates that the non-eosinophilic subtype of severe asthma is characterized by fixed airway obstruction, which may be related to emphysema. Transgenic studies have demonstrated that high levels of IFN-gamma in the airways induce emphysema. Fibroblast growth factor 2 (FGF2), which is the downstream mediator of TGF-beta, is important in wound healing. We investigated the role of FGF2 in IFN-gamma-induced emphysema and the therapeutic effects of recombinant FGF2 in the prevention of emphysema in a severe non-eosinophilic asthma model. To evaluate the role of FGF2 in IFN-gamma-induced emphysema, lung targeted IFN-gamma transgenic mice were cross-bred with FGF2-deficient mice. A severe non-eosinophilic asthma model was generated by airway application of LPS-containing allergens twice a week for 4 weeks. To evaluate protective effects of FGF2, recombinant FGF2 (10 microg) was injected subcutaneously during allergen challenge in the severe asthma model. We found that non-eosinophilic inflammation and emphysema induced by transgenic overexpression of IFN-gamma in the airways were aggravated by the absence of FGF2. Airway challenge with LPS-containing allergens induced more inflammation in mice sensitized with LPS-containing allergens compared to challenge with allergens alone. In addition, LPS-induced lung inflammation and emphysema depended on IFN-gamma but not on IL-13. Interestingly, emphysema in the severe asthma model was significantly inhibited by treatment with recombinant FGF2 during allergen challenge, whereas lung inflammation was unaffected. Therefore, our present data suggest that FGF2 may help protect against IFN-gamma-induced emphysema, and that recombinant FGF2 may help lessen the severity of emphysema.

IL-12-STAT4-IFN-gamma axis is a key downstream pathway in the development of IL-13-mediated asthma phenotypes in a Th2 type asthma model

IL-4 and IL-13 are closely related cytokines that are produced by Th2 cells. However, IL-4 and IL-13 have different effects on the development of asthma phenotypes. Here, we evaluated downstream molecular mechanisms involved in the development of Th2 type asthma phenotypes. A murine model of Th2 asthma was used that involved intraperitoneal sensitization with an allergen (ovalbumin) plus alum and then challenge with ovalbumin alone. Asthma phenotypes, including airway-hyperresponsiveness (AHR), lung inflammation, and immunologic parameters were evaluated after allergen challenge in mice deficient in candidate genes. The present study showed that methacholine AHR and lung inflammation developed in allergen-challenged IL-4-deficient mice but not in allergen-challenged IL-13-deficient mice. In addition, the production of OVA-specific IgG2a and IFN-gamma-inducible protein (IP)-10 was also impaired in the absence of IL-13, but not of IL-4. Lung-targeted IFN-gamma over-expression in the airways enhanced methacholine AHR and non-eosinophilic inflammation; in addition, these asthma phenotypes were impaired in allergen-challenged IFN-gamma-deficient mice. Moreover, AHR, non-eosinophilic inflammation, and IFN-gamma expression were impaired in allergen-challenged IL-12Rbeta2- and STAT4-deficient mice; however, AHR and non-eosinophilic inflammation were not impaired in allergen-challenged IL-4Ralpha-deficient mice, and these phenomena were accompanied by the enhanced expression of IL-12 and IFN-gamma. The present data suggest that IL-13-mediated asthma phenotypes, such as AHR and non-eosinophilic inflammation, in the Th2 type asthma are dependent on the IL-12-STAT4-IFN-gamma axis, and that these asthma phenotypes are independent of IL-4Ralpha-mediated signaling.

Role of breast regression protein-39/YKL-40 in asthma and allergic responses

BRP-39 and its human homolog YKL-40 have been regarded as a prototype of chitinase-like proteins (CLP) in mammals. Exaggerated levels of YKL-40 protein and/or mRNA have been noted in a number of diseases characterized by inflammation, tissue remodeling, and aberrant cell growth. Asthma is an inflammatory disease characterized by airway hyperresponsiveness and airway remodeling. Recently, the novel regulatory role of BRP-39/YKL-40 in the pathogenesis of asthma has been demonstrated both in human studies and allergic animal models. The levels of YKL-40 are increased in the circulation and lungs from asthmatics where they correlate with disease severity, and CHI3L1 polymorphisms correlate with serum YKL-40 levels, asthma and abnormal lung function. Animal studies using BRP-39 null mutant mice demonstrated that BRP-39 was required for optimal allergen sensitization and Th2 inflammation. These studies suggest the potential use of BRP-39 as a biomarker as well as a therapeutic target for asthma and other allergic diseases. Here, we present an overview of chitin/chitinase biology and summarize recent findings on the role of BRP-39 in the pathogenesis of asthma and allergic responses.

Chitin, Chitinases and Chitinase-like Proteins in Allergic Inflammation and Tissue Remodeling

Chitin, the second most abundant polysaccharide in nature after cellulose, consist exoskeleton of lower organisms such as fungi, crustaceans and insects except mammals. Recently, several studies evaluated immunologic effects of chitin in vivo and in vitro and revealed new aspects of chitin regulation of innate and adaptive immune responses. It has been shown that exogenous chitin activates macrophages and other innate immune cells and also modulates adaptive type 2 allergic inflammation. These studies further demonstrate that chitin stimulate macrophages by interacting with different cell surface receptors such as macrophage mannose receptor, toll-like receptor 2 (TLR-2), C-type lectin receptor Dectin-1, and leukotriene B4 recepptor (BLT1). On the other hand, a number of chitinase or chitinase-like proteins (C/CLP) are ubiquitously expressed in the airways and intestinal tracts from insects to mammals. In general, these chitinase family proteins confer protective functions to the host against exogenous chitin-containing pathogens. However, substantial body of recent studies also set light on new roles of C/CLP in the development and progression of allergic inflammation and tissue remodeling. In this review, recent findings on the role of chitin and C/CLP in allergic inflammation and tissue remodeling will be highlighted and controversial and unsolved issues in this field of studies will be discussed.

p53 Codon 72 and 16-bp Duplication Polymorphisms of Gastric Cancer in Koreans / 대한소화기학회지

BACKGROUND/AIMS: p53 gene plays an important role in cell cycle control in response to DNA damage which may increase the probability of mutations leading to carcinogenesis. The role of p53 gene polymorphisms [codon 72 (exon 4) and 16-bp duplication (intron 3)] as potential markers indicating cancer risk remains inconclusive, and the data on gastric cancer are very limited. The aim of this study was to assess the role of p53 gene polymorphisms in the risk of gastric cancer and in the determination of genetic susceptibility to gastric cancer in Koreans. METHODS: We analysed p53 genotypes using a polymerase chain reaction-based restriction fragment length polymorphism assay in a population-based case-control study in 120 gastric cancer patients and 145 cancer-free controls in Koreans. RESULTS: There was no specific genotype of p53 gene polymorphism in the gastric cancer patients compared to cancer-free controls. In p53 codon 72 and 16-bp duplication polymorphisms, the frequency and distribution of genotypes showed no statistical significance (p=0.7125 and p=0.1659). There was no difference in genotype by histologic subtypes, location of lesion, and age. However, the genotypic distribution in the patient subgroups with a history of heavy cigarette smoking of p53 16-bp duplication polymorphism were significantly different from those of cancer-free controls (p=0.0079). CONCLUSIONS: The p53 codon 72 and 16-bp duplication polymorphisms were not associated with the increased risk of gastric cancer and did not seem to contribute to gastric cancer susceptibility among Koreans. It is possible that p53 16-bp duplication polymorphism modulates the risk of smoking-induced gastric cancer development in Koreans. In order to clarify the associations between specific genotypes and gastric cancer risk, the evaluations of these polymorphisms in other ethnic backgrounds with larger number of patients would be needed.

A Study on the Loss of Heterozygosity of the p53 Gene in Primary Uterine Cervical Carcinomas / 대한암학회지

PURPOSE: Allelic deletion of p53 tumor suppressor gene have been observed frequently in a variety of human tumors. These losses are believed to contribute to the development of human cancers. But the loss of heterozygosity (LOH) data on chromosome 17p are rare and controversial with respect to cervical carcinomas. So, we tried to elucidate the frequency of p53 locus LOH in primary cervical carcinoma and compared the LOH data with clinicopathological parameters. MATERIALS AND METHODS: In order to detect LOH within one of the well-known tumor suppressor gene, p53, three intragenic polymorphisms (exon 1, exon 4, and intron 6) and one microsatellite distal to the p53 gene (D17S5) were examined. Paired DNA samples from 55 primary uterine cervical carcinomas and normal bloods were studied for the chromosomal allelic loss of p53 gene locus by polymerase chain reaction (PCR), the presence of human papilloma virus (HPV), and the presence of p53 gene point mutation by PCR-single conformation polymorphism (SSCP) analysis. And the relationships between allelic losses of this gene and conventional clinicopathological parameters were evaluated. RESULTS: We could increase the heterozygosity of the p53 gene up to 1 (100%). The observed allelic loss rate of the p53 locus in informative cases was 5.5% (3/55) and the observed allelic loss rate of the D17S5 locus in informative cases was 8.7% (4/46) . Only one of the four patients with LOH at the D17S5 locus showed a concomittant allelic loss of the p53 gene. The overall LOH incidence of the chromosomal region comprising 17p13.1 (p53) to 17p13.3 (D13S5) was 10.9% (6/55). All the samples contained at least one of the oncogenic HPV type 16 and/or 18 sequences. No shifted bands were observed in the PCR-SSCP analysis of the p53 gene. The LOH of the p53 gene was not related to other parameters including clinical stage, histological type, and degree of differentiation. CONCLUSION: Concerning with the results above, we conclude that the allelic imbalance of the p53 gene itself is not implicated as a major contributing factor in the malignant transformation or the tumor progression in HPV-positive cervical cancers. Another putative tumor suppressor gene which has more important function than p53 gene in cervical carcinogenesis might exist between these two loci [p53 (17p13.1) and D17S5 (17p13.3)].

Analysis of p53 and Retinoblasoma(Rb) Gene Polymorphisms in Relation to Lung Cancer in Koreans / 결핵

BACKGROUND: The p53 and retinoblastoma(Rb) tumor suppressor genes are associated with the pathogenesis of several types of human cancer. Substantial. proportion of the primary lung cancers or cell lines have been reported to have the p53 and/or the Rb gene mutations. But so far there is no report on the analysis of the Rb gene polymorphism as one of the genetic susceptibility marker. This study was undertaken to establish the gene frequencies of the polymorphic genotypes of the p53 and Rb genes in Koreans to evaluate the possible involvement of these genotypes as a risk factor of lung cancer. METHODS: In this study 145 controls without previous and present tumor history and 128 lung cancer patients were subjected to analysis The two intragenic polymorphisms of the p53 gene(exon 4/AccII, intron 6/MspI) and one intron 17/XbaI polymorphism of the Rb gene were analysed by the method of polymersae chain react lion-restriction fragment length polymorphisms(PCR-RFLPS). The genotype of the intron 3/16 bp repeat polymorphism of p53 was determined by PCR and direct gel electrophoresis. RESULTS: There were no significant differences in the genotype distributions of the p53 gene between lung cart cert patients and controls. But heterozygotes(Arg/Pro) of the exon 4/AcclII polymorphisms were slightly over-represented than controls, especially in the Kreyberg type I cancer, which was known 13 be associated with smoking. The intron 3/16 bp duplication and the intron 6/MspI polymorphisms were in complete linkage disequilibrium. About 95% of the individuals were homozygotes of the common alleles both in the 16 duplication and MspI polymorphisms, and no differences were deteced in the genotype distributions between lung cancer patients and controls. Overall genotype distributions of the Rb gene polymorphisms between lung cancer patients and controls were not significantly different However, the genotype distributions in the Kreyberg type I cancer were significantly different from those of controls(p=0.0297) or adenocarcinomas(p=0.0008). It was noticeable that 73.4% of the patients with adenocarcinomas were heterozygotes(r1/r2) whereas 39.2% of the Kreyberg type I cancer were heterozygous at this polymorphisms. In the lung cancer patients, significant differences were a]so noted between the high dose smokers and low dose smokers including non-smokers(p=0.0258). The relative risk to Kreyberg type I cancer was significantly reduced in the individuals with the genotype of r1/r2(odds ratio=0.46, 95%C.I.=0.25-0.86, p=0.0124). The combined genotype distribution of the exon 4/AccII of the p53 and the intron 17 Rb gene polymorphisms in Kreyberg type I cancers were significantly different from dose of controls or adenocarcinomas. The highest odds ratio were observed in the individuals with the genotypes of Arg/pro and r2/r2(odds ratio=1.97, 95%C.I.=0.84-4.59) and lowest one was in the patients with Arg/Arg, r1/r2 genotype(odds ratio=0.54, 95%C.I.=0.25-1.14). CONCLUSION: The p53 and the Rb gene polymorphisms modulate the risk of smoking induced lung cancer development in Koreans. However, the exact mechanism of risk modulation by these polymorphism remains to be determined. For more discrete clarification of associations between specific genotypes and lung cancer risk, the evaluations of these polymorphisms in other ethnics and more number of patients will be needed.

Cytochrome P450 2E1 Polymorphisms and Genetic Susceptibility to Cervical Cancer / 대한암학회지

PURPOSE: Interindividual genetic differences in susceptibility to chemical carcinogens are one of the most important host factors in human cancer. The genetically determined differences in metabolism, related to cytochrome P450 (CYP450) genes have been reported to be associated with various cancer susceptibility. The present study was set up to establish the frequency of the polymorphic genotypes of two CYP450 (CYP2E1/PstI and CYP2E1/DraI) isozymes in Korea, to evaluate a possible increased incidence of the genotype associated with higher cervical cancer risks among Korean cervical cancer patients. MATERIALS AND METHODS: In this study, extracted DNAs from 228 cervical cancer patients and 360 normal healthy controls were analysed with the polymerase chain reaction-restriction fragment length polymosphism (PCR-RFLP) method. RESULTS: In the CYP 2E1 genotypes, detected by PstI or RsaI digestion, there were no statistically remarkable differences between the cervical cancer patients and control groups. And when the cervical cancer patients were divided into subgroups with respect to the age, the frequency of CYP 2E1/PstI polymorphisms in the cervical cancer patients under the 40 years old was not significantly higher compared to the controls or the patients above the 40 years old and, c1/c1 genotype was prominent in this type of polymorphism. The frequency of CYP 2E1/DraI polymorphisms in the cervical cancer patients was not significantly higher compared to the controls, and D/D genotype was prominent in this type of polymorphism. In cervical carcinoma, the polymorphic genotypes of CYP 2E1 were not correlated to other parameters including clinical stage, histological tumor type, and degree of differentiation. CONCLUSION: These results suggest that individuals carrying CYP 2E1/PstI (c1/c1) or CYP 2E1/DraI (D/D) alleles are not genetically susceptible to cervical cancer in Korea.

Chromosime Analysis from Chorionic Villi Samples in Recurrent Sponataneous Abortion / 대한주산의학회잡지

Recurrent abortion has been defined as the occurrence of three or more clinically recognized pregnancy loss before 20 weeks and it occurs in 1% of women. The chromosomal abnormalities of abortuses have been suggested as the most common causes of recurrent abortion. We have studied the incidence of chromosomal abnormalities in 57 patients with recurrent abortion using the chorionic villi samples. Of the 57 abortuses analysed, 32 (56.1%) had chromosomal abnormalities. Trisomy was predominant (23 cases, 40.4%), followed by mosaicism 3 (5.2%), tetraploidy 2 (3.5%), monosomy 2 (3.5%), and structural anomaly 1 (1.8%). Trisomy for the chromosome 16 was most prevalent among trisomies. The incidence of trisomy was positively related to matemal age above 35 year-old. But there is not statistically significant. And there are no correlation between gestational age and chromosomal abnormalities. In conclusion, the incidence of chromosomal abnormalities of recurrent abortuses was 56.1% which was similar to that of the other reports. This means that the analysis of karyotype of chorionic villi, as the first test to investigate the cause of recurrent abortion, may be not useful, however, it will require further.

Glutathione S-Transferase Polymorphisms and Genetic Susceptibility to Cervical Cancer / 대한암학회지

PURPOSE: The identification of genetic traits that predispose individuals to environmentally induced cancers is one of the challanges in the assessment of individual cancer risk. The genetically determined differences in metabolism, related to glutathione S-transferases (GSTs) have been reported to be associated with various cancer susceptibility. The present study was set up to establish the frequencies of the polymorphic genotypes of two GST (GST- mu and GST-theta) isozymes in Korea, to evaluate a possible increased incidence of the genotypes associated with higher cervical cancer risks among Korean cervical cancer patients. MATERIALS AND METHODS: In this study, extracted DNAs from cervical cancer patients (228 for GST-mu and 241 for GST-theta genotypes) and normal controls (360 for GST-mu and 353 for GST-theta genotypes) were analysed with the polymerase chain reaction (PCR). RESULTS: The overall genotype distribution of the GST-theta polymorphisms was not statistically different between the patients and control groups. But, in the GST-mu null genotypes, there were remarkable differences between patients and control groups when the cervical cancer patients were devided into subgroups with respect to the age. The frequency of GST-mu null polymorphisms in the cervical cancer patients under the 40 years old was significantly higher compared to the patients above the 40 years old (0.01

Detection of the c-m c Oncogene Amplification in Ovarian Carcinomas by Differential Polymerase Chain Reaction

The amplification of c-myc oncogene was evaluated in 42 cases of ovarian carcinomas to correlate with clinical parameters. Using oligonucleotide primers, sequences from the c-myc exon-3 gene and from a control gene, tissue plasminogen activator (tPA), were amplified simultaneously by polymerase chain reaction (PCR). After the products of differential PCR (d-PCR) were electrophoresed, slot blot hybridization was performed, and hybridized with P32 dATP-labeled myc and tPA oligonucleotide probes and then autoradiographed. The signal intensities of the two products were quantitated by densitometry and the ratios of two products (c-myc/tPA) were measured. The ovarian carcinomas showed significantly increased amplification of c-myc oncogene Oligonucleoti compared to normal control group (p<0.05). 15 of 42 cases (35.7%) showed various degrees of the MYC gene amplification up to 27 folds in various histologic types of ovarian carcinomas. No significant differences of the MYC gene amplification according to histologic subtypes, tumor action) grades and clinical stages of ovarian carcinomas were present.

Molecular genetic study of St14.1(DXS52) TaqI RFLPs in Koreans for the diagnosis of hemophilia A / 대한산부인과학회잡지

No abstract available.