Reduced DNA-dependent protein kinase activity is associated with lung cancer.

Reduced DNA repair capacity of carcinogen-induced DNA damage is now thought to significantly influence inherent susceptibility to lung cancer. DNA-dependent protein kinase (DNA-PK) is a serine-threonine kinase activated by the presence of double-strand breaks in DNA that appears to play a major role in non-homologous recombination and transcriptional control. The purpose of this study was to determine whether DNA-PK activity varies among individuals and how this affects lung cancer risk. DNA-PK activity in peripheral mononuclear cells from individuals with lung cancer (n = 41) was compared with lung cancer-free controls (n = 41). Interindividual variability was seen within each group, however, significant differences (P = 0.03) in DNA-PK activity between cases and controls were seen when comparing the distribution of enzyme activity among these two groups. The percentages of cases and controls with DNA-PK activity in the ranges 2.5-5.0 and 7.6-10.0 units were 39 versus 20% and 7 versus 29%, respectively. The enzyme activity in peripheral mononuclear cells reflected that seen in bronchial epithelial cells, one progenitor cell for lung cancer, supporting the use of peripheral mononuclear cells for larger population-based studies of DNA-PK activity. Its role as a potential modifier for lung cancer risk was supported by the fact that cell growth in bronchial epithelial cells exposed to bleomycin was directly associated with enzyme activity. The results of this study demonstrate that reduced DNA-PK repair activity is associated with risk for lung cancer.

The XRCC1 399 glutamine allele is a risk factor for adenocarcinoma of the lung.

Defects in the repair and maintenance of DNA increase risk for cancer. X-ray cross-complementing group 1 protein (XRCC1) is involved with the repair of DNA single-strand breaks. A nucleotide substitution of guanine to adenine leading to a non-conservative amino acid change was identified in the XRCC1 gene at codon 399 (Arg/Gln). This change is associated with higher levels of aflatoxin B1-adducts and glycophorin A somatic mutations. A case-control study was conducted to test the hypothesis that the 399Gln allele is positively associated with risk for adenocarcinoma of the lung. XRCC1 genotypes were assessed at codon 399 in 172 cases of lung adenocarcinoma and 143 cancer-free controls. Two ethnic populations were represented, non-Hispanic White and Hispanic. The distribution of XRCC1 genotypes differed between cases and controls. Among cases, 47.7% were Arg/Arg, 35.5% were Arg/Gln, and 16.9% were Gln/Gln. Among controls, XRCC1 allele frequencies were 45.5% for Arg/Arg, 44.8% for Arg/Gln, and 9.8% for Gln/Gln. Logistic regression analysis was used to assess the association between lung adenocarcinoma and the G/G genotype relative to the A/A or A/G genotypes. In non-Hispanic White participants, the lung cancer risk associated with the G/G genotype increased significantly after adjustment for age (OR=2.81; 95% CI, 1.2-7.9; P=0.03) and increased further after adjustment for smoking (OR=3.25; 95% CI, 1.2-10.7; P=0.03). Among all groups, a significant association was found between the G/G homozygote and lung cancer (OR=2.45; 95% CI, 1.1-5.8; P=0.03) after adjustment for age, ethnicity, and smoking. This study links a functional polymorphism in the critical repair gene XRCC1 to risk for adenocarcinoma of the lung.

The lingula is an appropriate site for lung biopsy.

BACKGROUND: Lung biopsy is commonly performed for diagnosis of diffuse pulmonary disease. The lingula offers technical advantages for biopsy, however the quality of tissue obtained by lingula biopsy has been questioned. We sought to determine whether lingula biopsy was a satisfactory site for biopsy in terms of diagnostic yield, therapeutic interventions, and survival results. METHODS: All diagnostic lung biopsies performed for diffuse lung disease at 3 university affiliated hospitals between July 1, 1992 and December 31, 1998 were retrospectively reviewed. Patients were divided into 2 groups, depending upon site of biopsy: patients with lingula biopsy only and those with biopsies from other sites. RESULTS: There were 75 patients; 20 underwent biopsy of the lingula alone, 48 had biopsy of other sites with or without biopsy of the lingula, and location of biopsy was unknown in 7 patients. Histologic diagnosis was achieved in all patients. Significant beneficial therapeutic changes were made in 14 lingula patients, and consisted of immunosuppression in 12 cases. Three patients died in the hospital or within 30 days. Fourteen patients survived 1 year. There was no significant difference between patients that had biopsy of the lingula alone and those that had biopsies from other sites in urgency, technique, histologic diagnosis, rate of therapeutic interventions, hospital mortality, or 1 year survival. CONCLUSIONS: Lung biopsy of the lingula compared to other anatomic sites has equivalent diagnostic yield, therapeutic significance, and survival. Given the technical ease of biopsy, when disease is present radiographically it is the preferred site for lung biopsy.

Lung biopsy: is it necessary?

OBJECTIVE: Lung biopsy is associated with substantial mortality rates. We reviewed our experience with this operation, primarily in patients with immunocompetence, to determine whether the results justify the continued performance of this procedure. METHODS: We conducted a retrospective review of all diagnostic lung biopsies performed at 3 university-affiliated hospitals between July 1, 1992, and December 31, 1998. RESULTS: There were 75 patients: 25 patients were treated electively, 17 were treated on an urgent basis, 27 patients on an emergency basis, and the urgency was unclear in 6 patients. Significant beneficial therapeutic changes were made in 15 of 25 elective procedures (60%), in 16 of 17 urgent procedures (94%), and in 11 of 27 emergency procedures (41%; P =.001). Significant beneficial therapeutic changes consisted of immunosuppression in 13 of 15 (87%) patients treated on an elective basis, in 9 of 16 (56%) treated on an urgent basis, and in 9 of 11 (82%) treated on an emergency basis in whom therapy was altered (P =.14). Operative death was 0 of 25 for elective operations (0%), 3 of 17 for urgent operations (18%), and 14 of 26 for emergency operations (54%). Multivariable analysis of operative death showed urgency to be the only significant predictor of death (P =.002). CONCLUSIONS: In patients with immunocompetence, elective and urgent lung biopsies have acceptable operative mortality rates and frequently result in important beneficial therapeutic changes. Consequently biopsies are appropriate in these patients. Emergency biopsies are associated with high operative mortality rates and rarely result in a therapeutic change other than immunosuppression. These patients should not undergo lung biopsy if they are in stable condition and should be treated empirically with immunosuppression without operation if their condition is deteriorating.

Frequency of trisomy 20 in nonmalignant bronchial epithelium from lung cancer patients and cancer-free former uranium miners and smokers.

Lung cancer is the leading cause of cancer-related deaths. The development of sensitive screening methods to identify at-risk individuals before emergence of clinical disease would permit early intervention that could decrease this mortality. Our previous studies have shown that cells with trisomy 7 can be detected in bronchial epithelium from cancer-free smokers and former uranium miners. However, the use of more than one molecular marker could increase the chance of identifying at-risk individuals. Trisomy 20, which is found in 43-57% of non-small cell lung cancers, is a candidate marker. The purpose of the current investigation was to determine the percentage of cells with trisomy 20 in persons with a high risk for lung cancer. Bronchial epithelial cells that had been assayed for trisomy 7 were assayed for trisomy 20 by fluorescence in situ hybridization. Trisomy 20 was detected in bronchial epithelial cells from lung cancer patients and from smokers and ex-uranium miners without lung cancer. In some cases, patients who were negative for trisomy 7 exhibited trisomy 20. Consequently, more people with field cancerization were identified using both markers. However, the two markers combined did not appear to stratify the risk for lung cancer.

Mediastinitis without antecedent surgery.

The study evaluates the results of aggressive surgical treatment for mediastinitis without antecedent surgery, after retrospectively reviewing all patients with mediastinitis, excluding patients with prior cardiac, esophageal or mediastinal operations, treated between June 1, 1992 and August 1, 1996. 8 patients were treated. 7 were male, mean age was 58 years. The etiology was Boerhaave's syndrome in 4, iatrogenic injury in 2 and descending necrotizing mediastinitis in 2 patients. The mean number of operations was 2.5. The initial operation was through thoracotomy in 5 patients and sternotomy in 2 patients. 4 patients underwent neck drainage, 1 as primary treatment and 3 combined with transthoracic drainage. 1 patient received laparotomy. Mean hospitalization was 52 days (excluding 1 death). Complications included mechanical ventilation greater than 48 hours in 7 patients, 2 or more operations in 5 patients, multisystem organ failure in 5 patients and other complications in 6 patients. Death occurred in one patients. Mediastinitis without antecedent surgery is associated with significant morbidity, however, with aggressive surgical drainage 87% of patients survived.

Individuals at high risk for lung cancer have airway epithelial cells with chromosome aberrations frequently found in lung tumor cells.

Identification of individuals at greatest risk of developing lung cancer could enhance the efficacy of intervention modalities, thereby greatly reducing mortality from this disease. One strategy for identifying these people is to establish molecular markers which reflect the severity of their cancerization field. Thus, investigations were initiated to determine of cells with chromosome aberrations frequently exhibited by lung tumor cells, i.e., trisomy 7, trisomy 20, and deletion of 9p23, are prevalent within the uninvolved airways of cancer patients. As a result, cells containing these aberrations were consistently found at significantly elevated levels by using fluorescence in situ hybridization (FISH). In contrast, cells collected from non-smokers who had never smoked were normal by this assay. The next objective was to determine of cells exhibiting these alterations are also present in upper airways of exposed, but cancer-free smokers and ex-uranium miners. The results showed that, although only a subset of these people will develop lung cancer in their lifetimes, they universally harbor increased numbers of abnormal cells within their airway epithelium. However, the number of sites with multiple verities of abnormal cells tended to be fewer compared with the cancer patients. Thus, quantifying cells with molecular alterations within the cancerization field of a smoker may delineate those with a lesser grade of damage, and these individuals may be at a lesser risk of developing disease. However, differences in the extent of genetic damage afforded by these assays may not clearly define individuals with pending disease, and additional molecular assays must be devised.

Concurrent fluorescence in situ hybridization and immunocytochemistry for the detection of chromosome aberrations in exfoliated bronchial epithelial cells.

OBJECTIVE: A procedure was developed to allow concurrent detection of chromosome aberrations and identification of bronchial epithelial cells. STUDY DESIGN: Fluorescence in situ hybridization for chromosome 7 and immunocytochemistry for cytokeratin were performed on exfoliated bronchial epithelial cells in a sputum sample from a cancer patient. RESULTS: The Spectrum Orange-labeled alpha satellite probe for chromosome 7 produced red fluorescence, nuclei were counterstained with 4,6-diamidino-2-phenylindole (blue), and cytokeratin was visualized using a fluorescein isothiocyanate (FITC)-conjugated secondary antibody (green). CONCLUSION: This procedure allowed the rapid identification of airway epithelial cells with numerical chromosome aberrations in this sample. Ultimately, this procedure could increase the sensitivity and specificity of sputum cytology as a laboratory diagnostic tool for the early detection of lung cancer.

Molecular identification of individuals at high risk for lung cancer.

The objective of the work reviewed herein was to evaluate whether a cancerization field-consisting of cells with genetic alterations can be detected within normal-appearing bronchial epithelium. By using fluorescence in situ hybridization (FISH) for trisomy 7, cancerization fields were detected in the majority of cancer patients and also in significant percentages of cancer-free tobacco smokers and former uranium miners. These results suggest that molecular analyses may enhance the power of detecting premalignant changes in bronchial epithelium and may ultimately lead to identifying persons at greatest risk for developing lung cancer.

Adenocarcinoma of the lung presenting as a diffuse interstitial process in a 25-year-old man.

Adenocarcinoma of the lung is rare in young adults, particularly in persons below the age of 30. Younger patients tend to present with advanced stages of carcinoma, and often have a rapidly deteriorating course. We describe a 25-year-old male who presented with diffuse interstitial lung disease which was found at autopsy to be lymphangitic carcinomatosis of probable pulmonary origin.

Detection of trisomy 7 in nonmalignant bronchial epithelium from lung cancer patients and individuals at risk for lung cancer.

Early identification and subsequent intervention are needed to decrease the high mortality rate associated with lung cancer. The examination of bronchial epithelium for genetic changes could be a valuable approach to identify individuals at greatest risk. The purpose of this investigation was to assay cells recovered from nonmalignant bronchial epithelium by fluorescence in situ hybridization for trisomy of chromosome 7, an alteration common in non-small cell lung cancer. Bronchial epithelium was collected during bronchoscopy from 16 cigarette smokers undergoing clinical evaluation for possible lung cancer and from seven individuals with a prior history of underground uranium mining. Normal bronchial epithelium was obtained from individuals without a prior history of smoking (never smokers). Bronchial cells were collected from a segmental bronchus in up to four different lung lobes for cytology and tissue culture. Twelve of 16 smokers were diagnosed with lung cancer. Cytological changes found in bronchial epithelium included squamous metaplasia, hyperplasia, and atypical glandular cells. These changes were present in 33, 12, and 47% of sites from lung cancer patients, smokers, and former uranium miners, respectively. Less than 10% of cells recovered from the diagnostic brush had cytological changes, and in several cases, these changes were present within different lobes from the same patient. Background frequencies for trisomy 7 were 1.4 +/- 0.3% in bronchial epithelial cells from never smokers. Eighteen of 42 bronchial sites from lung cancer patients showed significantly elevated frequencies of trisomy 7 compared to never smoker controls. Six of the sites positive for trisomy 7 also contained cytological abnormalities. Trisomy 7 was found in six of seven patients diagnosed with squamous cell carcinoma, one of one patient with adenosquamous cell carcinoma, but in only one of four patients with adenocarcinoma. A significant increase in trisomy 7 frequency was detected in cytologically normal bronchial epithelium collected from four sites in one cancer-free smoker, whereas epithelium from the other smokers did not contain this chromosome abnormality. Finally, trisomy 7 was observed in almost half of the former uranium miners; three of seven sites positive for trisomy 7 also exhibited hyperplasia. Two of the former uranium miners who were positive for trisomy 7 developed squamous cell carcinoma 2 years after collection of bronchial cells. To determine whether the increased frequency of trisomy 7 reflects generalized aneuploidy or specific chromosomal duplication, a subgroup of samples was evaluated for trisomy of chromosome 2; the frequency was not elevated in any of the cases as compared with controls. The studies described in this report are the first to detect and quantify the presence of trisomy 7 in subjects at risk for lung cancer. These results also demonstrate the ability to detect genetic changes in cytologically normal cells, suggesting that molecular analyses may enhance the power for detecting premalignant changes in bronchial epithelium in high-risk individuals.

Cardiopulmonary manifestations of hantavirus pulmonary syndrome.

OBJECTIVE: To describe the clinical characteristics of a group of patients infected with the newly recognized hantavirus in the Southwestern United States. DESIGN: Case series. SETTING: Tertiary referral center. PATIENTS: All patients with confirmed hantavirus infection admitted to the University of New Mexico Hospital between May 1, 1993 and January 1, 1994. INTERVENTIONS: Records of patients with hantavirus infection were reviewed to collect all pertinent clinical data. MEASUREMENTS AND MAIN RESULTS: Pulmonary disease in these patients was characterized by hypoxemia covering a wide range of severity. The cause of hypoxemia was an increased permeability (noncardiac) pulmonary edema which could be differentiated from hydrostatic (cardiac) pulmonary edema by its association with low pulmonary artery occlusion pressures and increased protein content of edema fluid. Hemodynamic measurements in severe cases showed a shock state characterized by a low cardiac index (range 1.6 to 3.0 L/min/min2), a low stroke volume index (range 10.5 to 29 mL/m2), and high systemic vascular resistance index (range 1,653 to 2,997 dyne.sec/cm5.m2). Progression to death was associated with worsening cardiac dysfunction unresponsive to treatment and causing oxygen debt and lactic acidosis. CONCLUSIONS: The two major life-threatening pathophysiologic changes in Hantavirus Pulmonary Syndrome are increased permeability pulmonary edema, and an atypical form of septic shock caused by myocardial depression and hypovolemia.

Hyperoxic suppression of Fc-gamma receptor-mediated phagocytosis by isolated murine pulmonary macrophages.

Lower respiratory tract exposure to high oxygen (O2) concentrations is known to induce changes in pulmonary function through effects on several cell types located within the lung parenchyma, including pulmonary macrophages (PM). We studied the effects of hyperoxic exposure on phagocytosis via Fc-gamma receptors (FcR) on isolated murine PM. PM cultured in hyperoxic conditions exhibited little change in ingestion via FcR for up to 96 h, compared with significant increases in ingestion by PM cultured in 21% O2 over the same time period. This suppression was reversible and occurred whether 50 or 100% O2 concentrations were used for hyperoxic exposure. Addition of the potent macrophage-activating agent interferon-gamma (IFN-gamma) to cultured PM further increased FcR-mediated phagocytosis in normoxic PM but had no effect on PM cultured in 100% O2. Analysis of FcR expression by flow cytometry using monoclonal antibodies specific for two different FcR classes revealed that culture in normoxic conditions increased surface expression of both FcR classes. Hyperoxic culture inhibited up-regulation of the high-affinity FcR but did not affect low-affinity FcR up-regulation, suggesting that hyperoxic effects were not due solely to effects on regulation of FcR expression. However, hyperoxic exposure completely suppressed FcR-mediated actin polymerization. These findings suggest that hyperoxic exposure impairs PM ability to increase FcR-mediated phagocytic activity after appropriate stimulation, which could impair the lung's defenses against infection.

Intrapulmonary antigen deposition in the human lung: local responses.

We hypothesized that, as in animal models, localized deposition of antigen into the human lung would induce local inflammatory and immune responses in antigen-exposed sites. To test this hypothesis, segmental instillation of a well-characterized, highly immunogenic, soluble antigen, keyhole limpet hemocyanin (KLH) was performed in 10 healthy, nonsmoking volunteers. Ten to fifteen days after instillation, bronchoalveolar lavage (BAL) was performed in immunized segments (IS) and contralateral control segments (CS) and local responses to antigen instillation were assessed by comparing IS and CS BAL. Greater albumin concentrations and cell recoveries were found in IS than in CS BAL, suggesting local inflammation. Although total numbers of each cell type were increased, relative proportions of alveolar macrophages, lymphocytes, and neutrophils were similar in IS and CS BAL. CD4/CD8 ratios in IS BAL samples were greater than those in CS samples, because of higher numbers of CD4+ lymphocytes in IS than in CS BAL but similar numbers of CD8+ lymphocytes. Anti-KLH IgG and IgA concentrations were greater in IS than in CS BAL. However, anti-KLH IgG/albumin ratios were similar in IS BAL and serum, suggesting that anti-KLH IgG had reached IS by passive transudation from the circulation. In contrast, anti-KLH IgA/albumin concentrations were greater in IS BAL than in serum, suggesting local production, and/or active transport of serum-derived anti-KLH IgA into the IS. Fractionation of serum and IS BAL on sucrose gradients demonstrated that anti-KLH IgA activity was largely associated with 11S polymeric IgA in both locations.(ABSTRACT TRUNCATED AT 250 WORDS)

Alveolar and interstitial macrophage populations in the murine lung.

Pulmonary macrophages (PM) exist in two general anatomical compartments in the lower respiratory tract: the alveolar space (alveolar macrophages, AM) and the interstitium (interstitial macrophages, IM). We determined the relative contribution that macrophages in each of these compartments make to the size of the total PM population found in the lungs of C3H/OUJ mice, while also evaluating how efficiently bronchoalveolar lavage (BAL) removes AM from the murine lung. These objectives were accomplished by combining extensive BAL with subsequent mechanical and enzymatic dissociation of the lungs in conjunction with in situ and in vitro phagocytic assays involving opsonized erythrocytes (EA) to identify mononuclear phagocytes. On average, 2.5 x 10(6) cells were recovered by extensive BAL, and approximately 78% of these cells ingested EA in vitro. To determine the efficiency of BAL in removing PM from the alveolar space, EA were instilled intratracheally into intact lungs, which had been removed from the chest cavity, and allowed to incubate for 60 min; this was followed by exhaustive BAL and subsequent lung digestion. After these procedures, approximately 4% of the dissociated lung cells contained EA, indicating that these cells were alveolar in origin but had not been removed despite extensive BAL. Subtraction of these AM from the total EA+ cells in lung cell suspensions following a second in vitro incubation with EA indicated that approximately 37% of all PM were within the interstitium. These results suggest that, while AM comprise the majority of lung macrophages, IM constitute a larger component of the total PM population in murine lungs than previously reported. In addition, this study, like several previous investigations using other species, indicates that a significant proportion of AM remain in the lung despite attempts to remove them with BAL. Accordingly, residual AM significantly contaminate the IM population present in murine lung cell suspensions even after extensive lavage.

Neutrophil responses to intravascular pneumococcal sonicate.

Leukopenia and pulmonary leukostasis are prominent features in patients succumbing to pneumococcal (PNC) infections. We examined mechanisms involved in recruitment of polymorphonuclear neutrophils (PMNs) into pulmonary capillaries and alveolae after PNC sonicate injection. We showed that by 15 min postinjection, PMN chemotactic activity was found in bronchoalveolar lavage (BAL) fluids and increased with time until the end point of the study at 90 min. Accompanying the increased chemotactic activity in BAL fluids was a decrease in circulating PMNs more pronounced in the femoral artery (FA) than the pulmonary artery (PA). Superoxide anion (O2-) production by peripheral PMNs was depressed following PNC sonicate injection, and comparison of FA and PA showed that FA PMNs produced less O2- than PA PMNs. PA PMNs also showed enhanced random migration when compared to the depressed random migration of FA PMNs. This study demonstrated that an intravascular challenge of PNC sonicate was associated with increased chemotactic activity for PMNs in BAL fluid. Fewer PMNs and altered PMN function resulted from passage through the pulmonary microvasculature after PNC sonicate injection.

C-reactive protein receptors on the human monocytic cell line U-937. Evidence for additional binding to Fc gamma RI.

C-reactive protein (CRP) is an acute-phase protein that binds to components of damage tissue, activates C, and stimulates phagocytic cells. CRP binding to receptors on monocytic and polymorphonuclear phagocytes has been shown. Recently, CRP-binding proteins of 38 to 40 kDa and 57 to 60 kDa have been identified on the human promonocyte cell line U-937 and the mouse macrophage cell line PU5 1.8, respectively. However, analysis of CRP binding to these cells and to peripheral blood leukocytes suggests that additional CRP receptor sites may be present. Because many studies have shown interactions between CRP binding and IgG binding to leukocytes, we have examined further the CRP binding sites on U-937 cells and determined their relationship to the FcR for IgG (Fc gamma R) expressed on these cells. Our results demonstrate specific saturable binding of CRP to peripheral blood monocytes and U-937 cells, which is readily inhibited by aggregated IgG. Monomeric IgG, which binds specifically to Fc gamma RI, inhibited a maximum of 20% of CRP binding to these cells. mAb 197 and mAb IV.3, which block IgG binding to Fc gamma RI and Fc gamma RII, respectively, failed to inhibit CRP binding to U-937 cells. Two CRP-binding molecules were identified by precipitation of lysates from surface-labeled U-937 cells and cross-linking experiments. One of these had a molecular mass of 43 to 45 kDa, similar to the molecule previously described as the CRPR on U-937 cells. The other had the same mobility by SDS-PAGE as Fc gamma RI. The identity of this protein with Fc gamma RI was confirmed by the ability of both IgG-Sepharose and CRP-Sepharose to preclear the protein from cell lysates and by inhibition of binding to both IgG-Sepharose and CRP-Sepharose by anti-Fc gamma RI mAb 197.