Faculty Bibliography

Patients with resected, high-risk melanoma receive adjuvant immune checkpoint blockade (ICB), yet clinical benefit remains unpredictable, with 25%-40% of patients experiencing recurrence. To evaluate whether pre-treatment gut microbiome (GMB) features predict recurrence, we analyzed stool samples from 674 patients enrolled in a phase 3 clinical trial, CheckMate 915, which investigated the combination of nivolumab plus ipilimumab versus nivolumab as a single agent across five geographic regions. Region-specific and cross-region meta-analyses identified pre-treatment taxa associated with recurrence, including Eubacterium, Ruminococcus, Firmicutes, and Clostridium. Recurrence prediction was strongest when the validation cohort exhibited GMB profiles similar to those in the discovery cohort. Among closely matched individuals (Jensen-Shannon divergence [JSD] ≤ 0.11), the area under the curve (AUC) for recurrence prediction ranged from 0.78 to 0.94 across regions. GMB composition remained largely stable following treatment. These findings suggest that gut bacterial markers can predict recurrence after adjuvant ICB treatment in melanoma, supporting their potential as clinically actionable biomarkers to guide personalized therapy.

BACKGROUND:Asian American (AsA) and Native Hawaiian and Pacific Islander (NHPI) populations are underrepresented in U.S. health studies. OBJECTIVES/OBJECTIVE:The MOSAAIC (Multi-ethnic Observational Study in American Asian and Pacific Islander Communities) is a cohort study designed to improve understanding of disparities in cardiovascular disease and other health conditions affecting AsA and NHPI groups. METHODS:Through broad eligibility criteria and outreach tailored to each study community, MOSAAIC will include 11,500 adults aged 18+ years living in 5 field center regions: New York, Philadelphia, Chicago, San Francisco Bay Area, and Honolulu. The protocol specifies sample-size targets to allow valid comparisons among persons having personal or family origins in 4 geographically defined regions, including East Asia (the largest groups being Chinese and Korean), South Asia (Indian), Southeast Asia (Vietnamese and Filipino) and Oceania (NHPI). Measurements to be obtained at an in-person examination include clinical laboratory tests, medical history, medication use, spirometry, cognitive and physical function, anthropometry, and electrocardiogram. Surveys in multiple languages to assess medical, behavioral, lifestyle, social and environmental influences on health were developed by a multistep process to ensure equivalency between translations and cultural appropriateness. Biospecimens are stored for future studies. Long-term follow-up will be conducted to ascertain and adjudicate major health events including myocardial infarction, stroke, heart failure, and mortality. CONCLUSIONS:The National Institutes of Health established MOSAAIC as a resource for wide-ranging epidemiologic investigation of factors related to cardiometabolic, pulmonary, or mental health in persons of diverse AsA and NHPI background.

IMPORTANCE/UNASSIGNED:The oral microbiota may be involved in the development of pancreatic cancer, yet current evidence is largely limited to bacterial 16S amplicon sequencing and small retrospective case-control studies. OBJECTIVE/UNASSIGNED:To test whether the oral bacterial and fungal microbiome is associated with the subsequent development of pancreatic cancer. DESIGN, SETTING, AND PARTICIPANTS/UNASSIGNED:This cohort study used data from 2 epidemiological cohorts: the American Cancer Society Cancer Prevention Study-II Nutrition Cohort and the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial. Among cohort participants who provided oral samples, those who prospectively developed pancreatic cancer were identified during follow-up. Control participants who remained free of cancer were selected by 1:1 frequency matching on cohort, 5-year age band, sex, race and ethnicity, and time since oral sample collection. Data were collected from August 2023 to September 2024, and data were analyzed from August 2023 to January 2025. EXPOSURES/UNASSIGNED:The oral bacterial and fungal microbiome were characterized via whole-genome shotgun sequencing and internal transcribed spacer (ITS) sequencing, respectively. The association of periodontal pathogens of the red complex (Treponema denticola, Porphyromonas gingivalis, and Tannerella forsythia) and orange complex (Fusobacterium nucleatum, F periodonticum, Prevotella intermedia, P nigrescens, Parvimonas micra, Eubacterium nodatum, Campylobacter shower, and C gracilis) with pancreatic cancer was tested via logistic regression. The association of the microbiome-wide bacterial and fungal taxa with pancreatic cancer was assessed by Analysis of Compositions of Microbiomes With Bias Correction 2 (ANCOM-BC2). Microbial risk scores (MRS) for pancreatic cancer were calculated from the risk-associated bacterial and fungal species. MAIN OUTCOMES AND MEASURES/UNASSIGNED:Pancreatic cancer incidence. RESULTS/UNASSIGNED:Of 122 000 cohort participants who provided samples, 445 developed pancreatic cancer over a median (IQR) follow-up of 8.8 (4.9-13.4) years and were matched with 445 controls. Of these 890 participants, 474 (53.3%) were male, and the mean (SD) age was 67.2 (7.5) years. Three oral bacterial periodontal pathogens-P gingivalis, E nodatum, and P micra-were associated with increased risk of pancreatic cancer. A bacteriome-wide scan revealed 8 oral bacteria associated with decreased and 13 oral bacteria associated with increased risk of pancreatic cancer (false discovery rate-adjusted Q statistic less than .05). Of the fungi, genus Candida was associated with increased risk of pancreatic cancer. The MRS, based on 27 oral species, was associated with an increase in pancreatic cancer risk (multivariate odds ratio per 1-SD increase in MRS, 3.44; 95% CI, 2.63-4.51). CONCLUSIONS AND RELEVANCE/UNASSIGNED:In this cohort study, oral bacteria and fungi were significant risk factors for pancreatic cancer development. Oral microbiota hold promise as biomarkers to identify individuals at high risk of pancreatic cancer, potentially contributing to personalized prevention.

IMPORTANCE/UNASSIGNED:The oral microbiota may be involved in development of head and neck squamous cell cancer (HNSCC), yet current evidence is largely limited to bacterial 16S amplicon sequencing or small retrospective case-control studies. OBJECTIVE/UNASSIGNED:To test whether oral bacterial and fungal microbiomes are associated with subsequent risk of HNSCC development. DESIGN, SETTING, AND PARTICIPANTS/UNASSIGNED:Prospective nested case-control study among participants providing oral samples in 3 epidemiological cohorts, the American Cancer Society Cancer Prevention Study II Nutrition Cohort, the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial, and the Southern Community Cohort Study. Two hundred thirty-six patients who prospectively developed HNSCC were identified during a mean (SD) of 5.1 (3.6) years of follow-up. Control participants who remained HNSCC free were selected by 2:1 frequency matching on cohort, age, sex, race and ethnicity, and time since oral sample collection. Data analysis was conducted in 2023. EXPOSURES/UNASSIGNED:Characterization of the oral bacterial microbiome using whole-genome shotgun sequencing and the oral fungal microbiome using internal transcribed spacer sequencing. Association of bacterial and fungal taxa with HNSCC was assessed by analysis of compositions of microbiomes with bias correction. Association with red and orange oral pathogen complexes was tested by logistic regression. A microbial risk score for HNSCC risk was calculated from risk-associated microbiota. MAIN OUTCOMES AND MEASURES/UNASSIGNED:The primary outcome was HNSCC incidence. RESULTS/UNASSIGNED:The study included 236 HNSCC case participants with a mean (SD) age of 60.9 (9.5) years and 24.6% women during a mean of 5.1 (3.6) years of follow-up, and 485 matched control participants. Overall microbiome diversity at baseline was not related to subsequent HNSCC risk; however 13 oral bacterial species were found to be differentially associated with development of HNSCC. The species included the newly identified Prevotella salivae, Streptococcus sanguinis, and Leptotrichia species, as well as several species belonging to beta and gamma Proteobacteria. The red/orange periodontal pathogen complex was moderately associated with HNSCC risk (odds ratio, 1.06 per 1 SD; 95% CI, 1.00-1.12). A 1-SD increase in microbial risk score (created based on 22 bacteria) was associated with a 50% increase in HNSCC risk (multivariate odds ratio, 1.50; 95% CI, 1.21-1.85). No fungal taxa associated with HNSCC risk were identified. CONCLUSIONS AND RELEVANCE/UNASSIGNED:This case-control study yielded compelling evidence that oral bacteria are a risk factor for HNSCC development. The identified bacteria and bacterial complexes hold promise, along with other risk factors, to identify high-risk individuals for personalized prevention of HNSCC.

The human microbiome contributes metabolic functions, protects against pathogens, educates the immune system, and through these basic functions, directly or indirectly, affects most of our physiologic functions. Here, we consider the human microbiome and its relationship to several major noncommunicable human conditions, including orodigestive tract cancers, neurologic diseases, diabetes, and obesity. We also highlight the scope of contextual macroenvironmental factors (toxicological and chemical environment, built environment, and socioeconomic environment) and individual microenvironmental factors (smoking, alcohol, and diet) that may push the microbiota toward less healthy or more healthy conditions, influencing the development of these diseases. Last, we highlight current uncertainties and challenges in the study of environmental influences on the human microbiome and implications for understanding noncommunicable disease, suggesting a research agenda to strengthen the scientific evidence base.

Little is known regarding the impact of immigrant acculturation on the gut microbiome. We characterized differences in the gut microbiome between racially/ethnically diverse US immigrant and US-born groups, and determined the impact of dietary acculturation on the microbiome. Stool samples were collected from 863 US residents, including US-born (315 White, 93 Black, 40 Hispanic) and foreign-born (105 Hispanic, 264 Korean) groups. We determined dietary acculturation from dissimilarities based on food frequency questionnaires, and used 16S rRNA gene sequencing to characterize the microbiome. Gut microbiome composition differed across study groups, with the largest difference between foreign-born Koreans and US-born Whites, and significant differences also observed between foreign-born and US-born Hispanics. Differences in sub-operational taxonomic unit (s-OTU) abundance between foreign-born and US-born groups tended to be distinct from differences between US-born groups. Bacteroides plebeius, a seaweed-degrading bacterium, was strongly enriched in foreign-born Koreans, while Prevotella copri and Bifidobacterium adolescentis were strongly enriched in foreign-born Koreans and Hispanics, compared with US-born Whites. Dietary acculturation in foreign-born participants was associated with specific s-OTUs, resembling abundance in US-born Whites; e.g., a Bacteroides plebeius s-OTU was depleted in highly diet-acculturated Koreans. In summary, we observed that US nativity is a determinant of the gut microbiome in a US resident population. Dietary acculturation may result in loss of native species in immigrants, though further research is necessary to explore whether acculturation-related microbiome alterations have consequences for immigrant health.

BACKGROUND:Recent evidence suggests that immunotherapy efficacy in melanoma is modulated by gut microbiota. Few studies have examined this phenomenon in humans, and none have incorporated metatranscriptomics, important for determining expression of metagenomic functions in the microbial community. METHODS:In melanoma patients undergoing immunotherapy, gut microbiome was characterized in pre-treatment stool using 16S rRNA gene and shotgun metagenome sequencing (n = 27). Transcriptional expression of metagenomic pathways was confirmed with metatranscriptome sequencing in a subset of 17. We examined associations of taxa and metagenomic pathways with progression-free survival (PFS) using 500 × 10-fold cross-validated elastic-net penalized Cox regression. RESULTS:Higher microbial community richness was associated with longer PFS in 16S and shotgun data (p < 0.05). Clustering based on overall microbiome composition divided patients into three groups with differing PFS; the low-risk group had 99% lower risk of progression than the high-risk group at any time during follow-up (p = 0.002). Among the species selected in regression, abundance of Bacteroides ovatus, Bacteroides dorei, Bacteroides massiliensis, Ruminococcus gnavus, and Blautia producta were related to shorter PFS, and Faecalibacterium prausnitzii, Coprococcus eutactus, Prevotella stercorea, Streptococcus sanguinis, Streptococcus anginosus, and Lachnospiraceae bacterium 3 1 46FAA to longer PFS. Metagenomic functions related to PFS that had correlated metatranscriptomic expression included risk-associated pathways of L-rhamnose degradation, guanosine nucleotide biosynthesis, and B vitamin biosynthesis. CONCLUSIONS:This work adds to the growing evidence that gut microbiota are related to immunotherapy outcomes, and identifies, for the first time, transcriptionally expressed metagenomic pathways related to PFS. Further research is warranted on microbial therapeutic targets to improve immunotherapy outcomes.

BACKGROUND:Cancer recurrence after tumor resection in early-stage non-small cell lung cancer (NSCLC) is common, yet difficult to predict. The lung microbiota and systemic immunity may be important modulators of risk for lung cancer recurrence, yet biomarkers from the lung microbiome and peripheral immune environment are understudied. Such markers may hold promise for prediction as well as improved etiologic understanding of lung cancer recurrence. METHODS:In tumor and distant normal lung samples from 46 stage II NSCLC patients with curative resection (39 tumor samples, 41 normal lung samples), we conducted 16S rRNA gene sequencing. We also measured peripheral blood immune gene expression with nanoString®. We examined associations of lung microbiota and peripheral gene expression with recurrence-free survival (RFS) and disease-free survival (DFS) using 500 × 10-fold cross-validated elastic-net penalized Cox regression, and examined predictive accuracy using time-dependent receiver operating characteristic (ROC) curves. RESULTS:Over a median of 4.8 years of follow-up (range 0.2-12.2 years), 43% of patients experienced a recurrence, and 50% died. In normal lung tissue, a higher abundance of classes Bacteroidia and Clostridia, and orders Bacteroidales and Clostridiales, were associated with worse RFS, while a higher abundance of classes Alphaproteobacteria and Betaproteobacteria, and orders Burkholderiales and Neisseriales, were associated with better RFS. In tumor tissue, a higher abundance of orders Actinomycetales and Pseudomonadales were associated with worse DFS. Among these taxa, normal lung Clostridiales and Bacteroidales were also related to worse survival in a previous small pilot study and an additional independent validation cohort. In peripheral blood, higher expression of genes TAP1, TAPBP, CSF2RB, and IFITM2 were associated with better DFS. Analysis of ROC curves revealed that lung microbiome and peripheral gene expression biomarkers provided significant additional recurrence risk discrimination over standard demographic and clinical covariates, with microbiome biomarkers contributing more to short-term (1-year) prediction and gene biomarkers contributing to longer-term (2-5-year) prediction. CONCLUSIONS:We identified compelling biomarkers in under-explored data types, the lung microbiome, and peripheral blood gene expression, which may improve risk prediction of recurrence in early-stage NSCLC patients. These findings will require validation in a larger cohort.

BACKGROUND:Over 90% of Asian American (AsA) adults are first- or second-generation immigrants, undergoing substantial environmental and sociocultural transitions; yet most environmental epidemiology cohorts have included few AsA participants. METHODS:The Food and Microbiome Longitudinal Investigation (FAMiLI) is an environmental health cohort enriched with AsA adults (predominantly Korean and Chinese American) and designed to capture environmental exposures, dietary acculturation, and sociocultural factors across immigration generations. Its biobank-including buccal and stool specimens-supports research on the oral and gut microbiomes, human genomics, and other multi-omics. RESULTS:Since its launch in 2018, FAMiLI has completed baseline recruitment and biospecimen collection for 13,183 adults aged 40-75 years. The cohort is now expanding to include an additional 3,000 Asian American adults, bringing the total to approximately 16,000 participants, with an expected distribution of ~50% Asian American and ~50% from other racial/ethnic groups. This expansion provides an opportunity to examine AsA environmental health experiences within the broader U.S. CONCLUSIONS:FAMiLI is a unique national resource to address priority questions in environmental health, including microbiome and exposome science, individual susceptibility, and large-scale data analytics. IMPACT/CONCLUSIONS:The cohort supports investigation of critical windows of environmental change across the immigration experience, racial and ethnic disparities, and drivers of emerging health outcomes, including cancer, cardiovascular disease, diabetes and other outcomes. This cohort offers essential data to inform prevention strategies and shape public health policy to improve health outcomes in AsA communities.