Qiuyin Cai

MD, PhD

Vanderbilt University Medical Center

Professor

PLCO (Learn more about this study)

2019-1026

Jan 10, 2020

Helicobacter pylori strain-specific blood biomarker and lung cancer risk

Lung cancer is the leading cause of cancer death in the United States and many other countries. It has been suggested that infection play an important role in lung cancer risk. Helicobacter pylori (H. pylori) is one of the most common bacteria infecting humans. An increased seroprevalence of H. pylori was found in various respiratory diseases, such as chronic bronchitis and asthma. Multiple lines of evidence have emerged suggesting that H. pylori infection may increase the risk of lung cancer. In previous small case-control studies that investigated the association of H. pylori with lung cancer risk, H. pylori status was categorized in a dichotomous manner (H. pylori- vs. H. pylori+). In a study conducted within the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study (ATBC), cytotoxin-associated antigen (CagA) status was incorporated (H. pylori-; H. pylori+, CagA-; and H. pylori+, CagA+). Beside CagA, the previous studies did not evaluate other H. pylori biomarkers with lung cancer risk. A recently developed H. pylori multiplex serology method provides a sensitive high-throughput method to simultaneous detect antibodies to 15 H. pylori proteins. We hypothesize that H. pylori strain–specific infection may play a role in the etiology of lung cancer. We recently conducted a pilot study within the Southern Community Cohort Study (SCCS) to evaluate the association of H. pylori strain-specific blood biomarker with lung cancer risk. We found that antibodies to four H. pylori proteins were associated with risk of lung cancers. We plan to follow up these findings in PLCO, cohorts from Asia, and rest of cases in the SCCS. We will also investigate whether the association between H. pylori strain-specific infection and lung cancer risk differ by lung cancer histology types (adenocarcinoma vs. squamous cell carcinoma) and times between blood collection and cancer diagnosis. In addition, we will evaluate the possible interaction of H. pylori strain-specific infection with other lung cancer risk factors, particularly smoking and COPD, in relation to lung cancer risk. The proposed study may help understand of H. pylori infection and lung cancer risk, identify markers for lung cancer risk, and provide new information for a feasible cancer prevention strategy.

Aim 1: To conduct a nested case-control study to evaluate the association of H. pylori strain-specific biomarkers with lung cancer risk. We will include 1,615 lung cancer cases with pre-diagnostic serum/plasma samples and 1,615 matched controls from PLCO. H. pylori multiplex serology assays will be used to detect antibodies of 15 H. pylori proteins. Data from PLCO samples will be analyzed together with data from other cohorts.
Aim 2: To investigate whether the association between H. pylori strain-specific infection and lung cancer risk differ by lung cancer histology types (adenocarcinoma vs. squamous cell carcinoma) and times between blood collection and cancer diagnosis.

Aim 3. To evaluate the possible interaction of H. pylori strain-specific infection with other risk factors, particularly smoking and COPD, in relation to lung cancer risk.