Helicobacter pylori seroprevalence in patients with lung cancer

Hospital-Treated Infectious Diseases, Infection Burden, and Risk of Lung Cancer: An Observational and Mendelian Randomization Study

BACKGROUND

Although infections play a role in the development of lung cancer, the longitudinal association between infection and the risk of lung cancer is disputed, and data relating to pathogen types and infection sites are sparse.

RESEARCH QUESTION

How do infections affect subsequent lung cancer risk, and is the impact limited to specific microbes rather than infection burden?

STUDY DESIGN AND METHODS

Data on > 900 infectious diseases were gathered from the UK Biobank study. Short- and long-term effects of infections were assessed by using time-varying Cox proportional hazards models. The analysis was repeated, excluding patients with concurrent multi-pathogen infections or outcomes within the 10 years following the initial hospitalization for the index infection. A life table approach was used to estimate years of life lost from lung cancer. Infection burden was defined as the sum of the number of infection episodes over time and co-occurring infections. The genome-wide association studies used in two-sample Mendelian randomization were obtained from mostly European ancestry.

RESULTS

Hospital-treated infectious disease was associated with a greater risk of lung cancer (adjusted hazard ratio [aHR], 1.79; 95% CI, 1.74-1.83). aHRs for lung cancer ranged from 1.39 to 2.82 across pathogen types. The impact of lower respiratory tract infections (LRTIs) on lung cancer was the strongest, with an aHR of 3.22 (95% CI, 2.64-3.92); the aHR for extra-LRTIs was 1.29 (95% CI, 1.16-1.44). A dose-response association was observed between infection burden and lung cancer risk across different FEV1 percent predicted (Ptrend < .001). Multiple infections led to significant life lost from lung cancer at the age of 50 years. Mendelian randomization analysis reaffirmed the causal association.

INTERPRETATION

Both observational and genetic analyses suggest that infectious diseases could increase the risk of lung cancer. The dual perspective on the LRTIs and extra-LRTIs impacts may inform lung cancer prevention strategies.

Comparative Microbiomics Analysis of Antimicrobial Antibody Response between Patients with Lung Cancer and Control Subjects with Benign Pulmonary Nodules

BACKGROUND

CT screening can detect lung cancer early but suffers a high false-positive rate. There is a need for molecular biomarkers that can distinguish malignant and benign indeterminate pulmonary nodules (IPN) detected by CT scan.

METHODS

We profiled antibodies against 901 individual microbial antigens from 27 bacteria and 29 viruses in sera from 127 lung adenocarcinoma (ADC), 123 smoker controls (SMC), 170 benign nodule controls (BNC) individuals using protein microarrays to identify ADC and BNC specific antimicrobial antibodies.

RESULTS

Analyzing fourth quartile ORs, we found more antibodies with higher prevalence in the three BNC subgroups than in ADC or SMC. We demonstrated that significantly more anti-Helicobacter pylori antibodies showed higher prevalence in ADC relative to SMC. We performed subgroup analysis and found that more antibodies with higher prevalence in light smokers (≤20 pack-years) compared with heavy smokers (>20 pack-years), in BNC with nodule size >1 cm than in those with ≤1 cm nodules, and in stage I ADC than in stage II and III ADC. We performed multivariate analysis and constructed antibody panels that can distinguish ADC versus SMC and ADC versus BNC with area under the ROC curve (AUC) of 0.88 and 0.80, respectively.

CONCLUSIONS

Antimicrobial antibodies have the potential to reduce the false positive rate of CT screening and provide interesting insight in lung cancer development.

IMPACT

Microbial infection plays an important role in lung cancer development and the formation of benign pulmonary nodules.

Associations of lung cancer risk with biomarkers of Helicobacter pylori infection

Helicobacter pylori infection has been suggested to be associated with lung cancer risk. However, information is lacking on whether the association differs by H. pylori antigen. We conducted a nested case-control study within the Southern Community Cohort Study, including 295 incident lung cancer cases and 295 controls. Helicobacter pylori multiplex serology assay was performed to detect antibodies to 15 H. pylori proteins. Conditional logistic regression was used to estimate odds ratios (ORs) and confidence intervals (95% CIs) after adjustment for covariates. Overall H. pylori+ was associated with a non-statistically significant increased risk of lung cancer (OR: 1.29; 95% CI: 0.85-1.95). Significant associations, however, were observed for H. pylori+ VacA+ (OR: 1.64; 95% CI: 1.02-2.62) and H. pylori+ Catalase+ (OR: 1.75; 95% CI: 1.11-2.77). The positive association of H. pylori+ Catalase+ with lung cancer risk was predominantly seen among African Americans (OR: 2.09; 95% CI: 1.11-3.95) but not European Americans (OR: 1.20; 95% CI: 0.56-2.54). Among participants who smoked ≥ 30 pack-years, overall H. pylori+ (OR: 1.85; 95% CI: 1.02-3.35), H. pylori+ CagA+ (OR: 2.77; 95% CI: 1.35-5.70), H. pylori+ VacA+ (OR: 2.53; 95% CI: 1.25-5.13) and H. pylori+ HP1564+ (OR: 2.01; 95% CI: 1.07-3.77) were associated with increased risk of lung cancer. Our study provides novel evidence that associations of H. pylori infection with lung cancer risk differ by H. pylori biomarker, may be more evident among African Americans and may be modified by smoking habits. Furthermore, studies are warranted to confirm our findings.

Helicobacter pylori and Respiratory Diseases: 2021 Update

Helicobacter pylori (H. pylori) is a Gram-negative bacterium involved in the development of gastritis, peptic ulcer disease, gastric adenocarcinoma, and gastric mucosa-associated lymphoid tissue. Unexplained iron deficiency anemia, idiopathic thrombocytopenic purpura and vitamin B12 deficiency have also been related to H. pylori infection, whereas for other extra-gastric diseases, the debate is still open. In this review, we evaluate and discuss the potential involvement of H. pylori infection in the pathogenesis of several respiratory diseases. A MEDLINE search of all studies published in English from 1965 to 2021 was carried out. Controversial findings have been reported in patients with bronchial asthma, chronic obstructive pulmonary disease, bronchiectasis, lung cancer, tuberculosis, cystic fibrosis, and sarcoidosis. Most of the available literature is concerned with case-control studies based on seroprevalence, with a small sample size and low consideration of confounders, which represents a potential issue. So far, there is no clear evidence of a causal association between H. pylori infection and respiratory diseases, and larger studies with appropriate epidemiological design are required.

Does Helicobacter pylori Infection Play a Role in Susceptibility to Brucellosis?

Brucellosis is endemic in Iran. Several studies have shown that brucellosis is associated with other infectious diseases. This study aimed to determine the relationship between Helicobacter pylori (HP) and brucellosis. In this case-control study, 100 patients with brucellosis as cases and 200 participants without brucellosis as controls were evaluated. To compare the prevalence of HP in the 2 groups, odds ratios and confidence intervals for every variable were analyzed using logistic regression models after adjustment for confounding factors. The results obtained in patients with brucellosis showed that fever, sweating, and joint pain were the most prevalent clinical symptoms. In addition, compared with the control group, there was a significant relationship between the IgM antibody to HP and brucellosis infection (estimated odds ratio 2.74; 95% CI: 1.5-4.9) (p = 0.001). Acute infection with HP was associated with brucellosis and increased the risk of brucellosis infection.

Association between Helicobacter pylori and mortality in the NHANES III study

OBJECTIVE

Persistent colonisation by Helicobacter pylori, and especially by cagA-positive strains, has been related to several health outcomes with effects in opposite directions. Thus, it is important to evaluate its influence on total and category-specific mortality.

DESIGN

We conducted prospective cohort analyses in a nationally representative sample of 9895 participants enrolled in the National Health and Nutrition Examination Survey III to assess the association of H pylori status with all-cause and cause-specific mortality. Analyses for the association of H pylori cagA positivity with mortality were conducted in 7384 subjects with data on H pylori cagA status.

RESULTS

In older people (> 40.1 years), H pylori was not associated with all-cause mortality (HR 1.00; 95% CI 0.84 to 1.18). There was an inverse association of H pylori status with stroke mortality (HR 0.69; 95% CI 0.44 to 1.08), and the inverse association was stronger for H pylori cagA positivity, with the HR of 0.45 (95% CI 0.27 to 0.76). H pylori was also strongly positively related to gastric cancer mortality. After we adjusted p values using the Benjamini-Hochberg false discovery rate method to account for multiple comparisons, these associations remained, and H pylori status was not related to other outcomes.

CONCLUSIONS

Our findings suggest that H pylori has a mixed role in human health, but is not a major risk factor for all-cause mortality.

Helicobacter pylori infection and lung cancer: a review of an emerging hypothesis

Helicobacter pylori (Hp) is one of the most common bacteria infecting humans. Recently, certain extragastric manifestations, linked to Hp infection, have been widely investigated, suggesting that Hp infection might be a 'systemic' disease. Accumulating, yet limited, evidence points to a potential association between Hp infection and lung cancer risk. Epidemiologic studies have shown that odds ratios (estimated relative risks) of lung cancer with Hp infection range from 1.24 to 17.78 compared with the controls, suggesting an increased lung cancer risk in the population exposed to Hp infection although far from supporting a causal relationship between Hp and lung cancer. Many studies have demonstrated the existence of Hp in the mucosa of the upper respiratory tract with no direct evidence of Hp-localization in lung tissue in the published literatures, rendering the possible functional mechanism underlying the association an open question. We followed the classic hypothesis-generating path, where we have thoroughly reviewed the publications on lung cancer and Hp infection from serological association to possible mechanisms as: (i) p130cas activated by Src kinase following Hp-host communication and p130cas-related carcinogenesis as in various malignancies; and (ii) gastroesophageal reflux and inhalation of urease or gastrin, which are Hp-related carcinogenic factors and present in lung tissues. We propose rigorous investigations regarding the Hp-lung cancer association and, if confirmed, the mechanisms of Hp infection leading to lung cancer development and progression. Clarification on Hp-lung cancer association is important for the understanding of lung cancer beyond tobacco-smoking-related carcinogenesis.

Helicobacter pylori Infection and Risk of Lung Cancer: A Meta-Analysis

Background. Recent evidence showed that Helicobacter pylori seropositivity is a risk factor for gastric and several other cancers. However, evidence on H. pylori infection and risk of lung cancer has been controversial, with a limited number of underpowered studies. We therefore examined the association between H. pylori infection and risk of lung cancer. Methods. A comprehensive literature search was performed using PubMed, EMBASE (until October 2012) for studies investigating an association between Helicobacter pylori (H. pylori) infection and risk of lung cancer. Pooled odds ratio (OR) was calculated using random-effects model. Subgroup and sensitivity analysis were also done. Results. A total of seven studies (6 case-control and 1 cohort study) were included for the analysis. There was a significant heterogeneity among the studies, but no publication bias was observed. We found that H. pylori infection was associated with significantly increased risk of lung cancer (pooled OR, 2.29 (95% CI, 1.34–3.91) P = 0.01). Conclusions. Our meta-analysis suggests a significant increased risk of lung cancer in patients with H. pylori infection. Further research is needed to confirm these findings and to identify the underlying biological mechanisms.

Urease and Helicobacter spp. antigens in pulmonary granuloma

Pulmonary sarcoidosis, a human disease of unknown cause, has no animal model. Sarcoidosis patients have serum antibodies specific for Helicobacter pylori and its surface enzyme urease. H. pylori do not survive in the high-oxygen pulmonary atmosphere, but urease may access the lung by oesophageal reflux. A model was established in rats to study gastro-oesophageal reflux of urease into the airways. Pathology in tissues from human sarcoidosis patients was compared with that in the rat model. Changes observed in the rat model included prominent peribronchial lymphocytic infiltration, which is seen occasionally in human sarcoidosis. Granulomas, pathognomonic for human sarcoidosis, occurred occasionally in the lungs of rats given urease protein intratracheally, but were widespread when urease was coupled to microbeads and administered intravenously. Biomarkers associated with human sarcoidosis (interleukin1-β and platelet-activating factor) were up-regulated acutely in the rat model. Further investigations with this model may provide significant insights into the origin and pathogenesis of pulmonary diseases in man and other species that carry gastric Helicobacter spp. and its associated enzyme.

Helicobacter pylori seropositivity and risk of lung cancer

Lung cancer is the leading cause of cancer mortality worldwide. Helicobacter pylori (H. pylori) is a risk factor for distal stomach cancer, and a few small studies have suggested that H. pylori may be a potential risk factor for lung cancer. To test this hypothesis, we conducted a study of 350 lung adenocarcinoma cases, 350 squamous cell carcinoma cases, and 700 controls nested within the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study (ATBC) cohort of male Finnish smokers. Controls were one-to-one matched by age and date of baseline serum draw. Using enzyme-linked immunosorbent assays to detect immunoglobulin G antibodies against H. pylori whole-cell and cytotoxin-associated gene (CagA) antigens, we calculated odds ratios (ORs) and 95% confidence intervals (95% CIs) for associations between H. pylori seropositivity and lung cancer risk using conditional logistic regression. H. pylori seropositivity was detected in 79.7% of cases and 78.5% of controls. After adjusting for pack-years and cigarettes smoked per day, H. pylori seropositivity was not associated with either adenocarcinoma (OR: 1.1, 95% CI: 0.75–1.6) or squamous cell carcinoma (OR: 1.1, 95% CI: 0.77–1.7). Results were similar for CagA-negative and CagA-positive H. pylori seropositivity. Despite earlier small studies suggesting that H. pylori may contribute to lung carcinogenesis, H. pylori seropositivity does not appear to be associated with lung cancer.

Role of bacteria in oncogenesis

Although scientific knowledge in viral oncology has exploded in the 20th century, the role of bacteria as mediators of oncogenesis has been less well elucidated. Understanding bacterial carcinogenesis has become increasingly important as a possible means of cancer prevention. This review summarizes clinical, epidemiological, and experimental evidence as well as possible mechanisms of bacterial induction of or protection from malignancy.

Assessment of the relationship between Helicobacter pylori and lung cancer: a meta-analysis

BACKGROUND AND AIMS

Helicobacter pylori infection has been thought to play a critical role in gastric carcinoma tumorigenesis and progression. Several studies have been devoted to the relationship between H. pylori infection and lung cancer risk and have generated inconclusive results. In this study we aimed to evaluate the potential association of H. pylori infection with lung cancer risk.

METHODS

We conducted a search in Medline, OVID, EMBASE and CNKI, covering all published papers until October 2008. The relevant published papers were deliberately selected according to the established inclusion criteria for publications. Essential data were then extracted from the included studies and further analyzed by a systematic meta-analysis.

RESULTS

A total of 98 papers were identified. Of these, four case-control studies met the inclusion criteria and thus were finally selected. Lung cancer risk for H. pylori infection was 3.24-fold (95% CI=1.11-9.47) (Z=2.15, p<0.05) compared with the controls.

CONCLUSIONS

The pooled data suggest infection of H. pylori as a potential risk factor for lung cancer.

H pylori seroprevalence in patients with lung cancer

AIM: To assess H pylori seroprevalence in lung cancer and determine whether there is a potential association between lung cancer and H pylori infection.

METHODS: The study was conducted on forty consecutive patients with lung cancer, confirmed by pathology (32 men, 8 women; mean age 55.50 ± 11.91 years, range 16-77 years). Forty healthy subjects (25 men, 15 women; mean age 43.08 ± 12.60 years, range 20-79 years) from the patients’ family members were matched to each case subject on the basis of age and socioeconomic status. H pylori infection was detected with a commercially available immunoglobulin G (IgG) enzyme-linked immunosorbent assay (Trinity kit, Biotech co., USA), previously validated in adults (86% sensitivity, 96% specificity) against a gold standard of culture and histology.

RESULTS: H pylori seropositivity was present in 52.5% of patients with lung cancer in comparison to 45.0% of healthy control subjects. Although H pylori seropositivity was more frequent in lung cancer patients than in controls, the difference did not reach statistical significance (OR = 1.35, 95% CI = 0.56-3.25; P = 0.65). In addition, there was no significant difference between cases and controls in terms of gastrointestinal symptoms.

CONCLUSION: The earlier described association between H pylori infection and lung cancer was not supported in this study. Further studies with larger sample sizes should be undertaken to assess the frequency of H pylori infection in patients with lung cancer and their potential association.

Helicobacter pylori in Bronchiectasis: A Polymerase Chain Reaction Assay in Bronchoalveolar Lavage Fluid and Bronchiectatic Lung Tissue

BACKGROUND

A number of studies have implicated an association between H. pylori and diverse extra-gastroduodenal pathologies. Chronic inflammation and increased immune response have been observed in bronchiectasis, likely gastroduodenal inflammatory diseases. H. pylori has been found in the trachea-bronchial aspirates of mechanically ventilated patients. Furthermore, the seroprevalence of H. pylori was found to be significantly higher in patients with bronchiectasis than in the control group. The present study was performed to investigate the possible role of H. pylori in the pathogenesis of bronchiectasis.

METHODS

Prospectively, bronchoalveolar lavage fluid (BALF) was obtained from patients with bronchiectasis (n=26) and control (n=20). BALF was subjected to polymerase chain reaction (PCR) to determine the presence of H. pylori and serum IgG against H. pylori was determined with micro-ELISA kit. In addition, PCR was performed to determine H. pylori in surgically removed lung tissues from patients with bronchiectasis (n=97).

RESULTS

H. pylori DNA was not detected in the BALF or in lung tissue samples. In addition, anti-H. pylori IgG level in patients with bronchiectasis did not show statistically significant difference from that of the control.

CONCLUSIONS

Our study provided evidence that there might be no direct association between H. pylori and bronchiectasis; however, the indirect role of soluble products of H. pylori could not be excluded.

Some fibrocystic breast change may be caused by sexually transmitted H. pylori during oral nipple contact: supporting literature and case report of resolution after gut H. pylori eradication treatment

OBJECTIVES

To briefly review previously published evidence for Helicobacter pylori (Hp), colonization of extra-intestinal sites and suggest an hypothesis that breast acini and ducts be added to this list, concluding such breast colonization is not rare and is a sexually transmitted infection.

METHODS

PubMed literature search and review with a case report.

CONCLUSIONS

(1) Evidence indicates oral Hp is common and can remain in the mouth after successful eradication in stomach and duodenum. (2) Evidence indicates that the breast is also occasionally colonized by Hp. (3) Hp may be injected retrograde up into ducts of the breast during oral nipple stimulation during sexual activity and this Hp may give rise to some cases of fibrocystic breast change. (4) A case of painful fibrocystic change that had been present for two years in a 27 year old female, resolved after gastrointestinal Hp treatment.

Helicobacter pylori infection as a possible risk factor for respiratory system disease: a review of the literature

Helicobacter pylori (HP) infection may cause extradigestive manifestations directly or indirectly, by potential mechanisms. HP infection triggers a marked local inflammatory response and a chronic systemic immune response. Some of the mediators that are thought to be possibly involved in the pathogenesis of extradigestive diseases caused by HP infection include IL-1, TNF-alpha, interferon (IFN)-gamma, leukotriene C4 and platelet-activating factor. Previous epidemiological and serological case control studies have revealed that HP infection might have a role in the development of chronic bronchitis, bronchiectasis, lung cancer and tuberculosis. However HP infection does not appear to have a role in the development of bronchial asthma. Considering the importance and prevalence of respiratory system diseases, it may be time to conduct well-designed sets of studies to clarify whether there is an association with HP infection and respiratory system diseases, and to answer questions that have been posed regarding the patterns of histology, genotypes of HP, and the effects of eradication therapy. The aim of this review was to analyze the possible association between HP and respiratory disease and provide a critical review of the relevant literature.

Respiratory diseases and Helicobacter pylori infection: is there a link?

Recent studies suggest an epidemiological association between Helicobacter pylori infection and several extra-gastroduodenal pathologies, including cardiovascular, rheumatic, skin and liver diseases. The observed associations might be explained by a role of H. pylori infection in the pathogenesis of certain extra-digestive disorders, as a variety of inflammatory mediators are activated by H. pylori infection. The present review summarizes the current literature, including our own studies, concerning the association between respiratory diseases and H. pylori infection. A small number of epidemiological and serologic case-control studies suggest that patients with chronic obstructive pulmonary disease have an increased seroprevalence of H. pylori. A frequent coexistence of bronchiectasis and H. pylori infection has also been found. Moreover, recent studies have shown an increased prevalence of H. pylori infection in patients with pulmonary tuberculosis and in those with lung cancer. On the other hand, bronchial asthma does not seem to be related to H. pylori infection. At present, there is no definite proof of a causal relationship between H. pylori and respiratory diseases. The primary evidence rests on case-control studies, concerning relatively small numbers of patients. Future studies should be large enough for moderate-sized effects to be assessed or registered reliably. The activation of inflammatory mediators by H. pylori infection might be the pathogenetic mechanism underlying the observed associations. Therefore, the role of genetic predisposition of the infected host, the presence of strain-specific virulence factors and the serum concentration of proinflammatory markers in H. pylori-infected patients with respiratory diseases need further evaluation.

Helicobacter pylori seroprevalence in patients with chronic obstructive pulmonary disease and its relation to pulmonary function tests

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is a slowly progressive condition characterized by poorly reversible airflow limitation that is associated with an abnormal inflammatory response of the lung. It has been shown that there is a seroepidemiological association of Helicobacter pylori (Hp) infection with many inflammatory conditions.

OBJECTIVE

In this study, we aimed to investigate seroprevalence in Hp patients with COPD and to determine whether there is an association between Hp infection and COPD.

METHODS

Forty-nine voluntary patients with COPD and 50 healthy control subjects of similar age and sex were included in the study. Hp-specific IgG was measured with a commercially available kit from venous blood samples.

RESULTS

Serum levels of Hp-specific IgG and Hp IgG seropositivity were significantly higher in the patients with COPD than in the control subjects (p < 0.001 and p = 0.006, respectively). In addition, when the patients with COPD were grouped according to Hp IgG seropositivity, forced expiratory volume in 1 s (FEV(1)) values were lower in the seropositive patients compared to seronegative patients, and Hp serum IgG levels were correlated with FEV(1) values, which indicate the severity of COPD, in the COPD group (r = -0.306, p = 0.032).

CONCLUSION

The results suggest that there is an association between Hp infection and COPD, and Hp IgG levels are correlated with the severity of COPD.

Helicobacter pylori and extragastric diseases--other Helicobacters

The involvement of Helicobacter pylori in the pathogenesis of extragastric diseases continues to be an interesting topic in the field of Helicobacter-related pathology. Although conflicting findings have been reported for most of the disorders, a role of H. pylori seems to be important especially for the development of cardiovascular and hematologic disorders. Previously isolated human and animal Helicobacter sp. flexispira and "Helicobacter heilmannii" strains have been validated using polyphasic taxonomy. A novel enterohepatic Helicobacter has been isolated from mastomys and mice, adding to the list of helicobacters that colonize the liver. Genetic targets that may aid the classification of novel Helicobacter species have emerged. Animal models of Helicobacter-induced gastric and hepatobiliary diseases have offered insights to the mechanisms associated with premalignant transformation.

Does Helicobacter pylori infection play a role in lung cancer?

BACKGROUND

Helicobacter pylori infection is a world-wide common disease and leads to many gastrointestinal and respiratory illnesses. It is suggested that one of these respiratory illnesses is lung cancer.

METHODS

Forty-three patients with non-small cell lung cancer and 28 control subjects have been included to this study. H. pylori status of the patients and controls was determined by immunoblot for the detection of IgG (RIDA Blot Helicobacter). All subjects were examined to evaluate the presence of VacA and CagA gene.

RESULTS

Seropositivity of anti H. pylori IgG was significantly higher in cancer patients than in control groups, 40 (93%) and 12 (42%), respectively (P<0.01). Although both VacA and CagA seropositivity was high in lung cancer patients, only VacA positivity was statistically significant when compared with control subjects, 35 (81%) and 11 (42%), respectively (P<0.05).

CONCLUSION

H. pylori infection may be associated with development of lung cancer.