Circulating Inflammation Proteins Associated With Lung Cancer in African Americans

Chronic periodontitis and risk of lung cancer: a nationwide cohort study

Background

The impact of long-term chronic periodontal conditions on the risk of lung cancer could not be accurately evaluated. Our aim was to provide more evidence on the connection between chronic periodontitis (CP) and lung cancer using a nationwide dataset.

Methods

This study used data from the Korean National Health Insurance Service National Sample Cohort. We enrolled 72,658 individuals with CP (CP cohort) between 2005 and 2019 and 1:1 age- and sex-matched controls without CP (non-CP cohort).

Results

During the median follow-up period of 5.1 (interquartile range, 2.8-8.0) years, 0.56% (n = 405/72,658) of the CP cohort and 0.29% (n = 212/72,658) of the matched non-CP cohort developed lung cancer, with incidence rates of 8.3 and 4.5 per 10,000 person-years. The risk of incident lung cancer was significantly higher in the CP cohort than in the matched non-CP cohort (adjusted hazard ratio = 2.27, 95% confidence interval = 1.94-2.65). The risk of incident lung cancer was 2.45-fold and 2.10-fold higher in mild and moderate-to-severe CP cohorts than in the matched non-CP control. The risk of incident lung cancer was especially higher in the 40-59 age group, females, and never-smokers than their counterparts.

Conclusion

We demonstrate that the risk of incident lung cancer is higher in individuals with CP than in those without. The risk of lung cancer was especially high in individuals with more severe CP, females, never-smokers, and obese populations.

Differences in systemic immune parameters in individuals with lung cancer according to race

Introduction

Racial and ethnic disparities in the presentation and outcomes of lung cancer are widely known. To evaluate potential factors contributing to these observations, we measured systemic immune parameters in Black and White patients with lung cancer.

Methods

Patients scheduled to receive cancer immunotherapy were enrolled in a multi-institutional prospective biospecimen collection registry. Clinical and demographic information were obtained from electronic medical records. Pre-treatment peripheral blood samples were collected and analyzed for cytokines using a multiplex panel and for immune cell populations using mass cytometry. Differences between Black and White patients were determined and corrected for multiple comparisons.

Results

A total of 187 patients with non-small cell lung cancer (Black, 19; White, 168) were included in the analysis. There were no significant differences in baseline characteristics between Black and White patients. Compared to White patients, Black patients had significantly lower levels of CCL23 and CCL27, and significantly higher levels of CCL8, CXCL1, CCL26, CCL25, CCL1, IL-1 b, CXCL16, and IFN-γ (all P <0.05, FDR<0.1). Black patients also exhibited greater populations of non-classical CD16+ monocytes, NKT-like cells, CD4+ cells, CD38+ monocytes, and CD57+ gamma delta T cells (all P <0.05).

Conclusions

Black and White patients with lung cancer exhibit several differences in immune parameters, with Black patients exhibiting greater levels of numerous pro-inflammatory cytokines and cell populations. The etiology and clinical significance of these differences warrant further evaluation.

Cytokine Signatures for Lung Cancer Diagnosis in African American Populations

Lung cancer is the leading cause of cancer-related deaths among both men and women. African Americans (AAs) experience disproportionately higher incidence and mortality compared to other ethnic groups. Cytokines play multifaceted and crucial roles in the initiation, progression, and spread of cancer. Our aim was to identify cytokine biomarkers for the early detection of lung cancer in AAs. We examined eight key cytokines (Interleukin-1, IL-6, IL-8, IL-10, IL-12p70, monocyte chemotactic protein-1 (MCP-1), interferon-gamma (IFN-γ), and tumor necrosis factor-alpha (TNF-α)) in the plasma of 104 lung cancer patients and 48 cancer-free individuals using the FirePlex Immunoassay. These findings were subsequently validated in a separate cohort of 58 cases and 58 controls. IL-8, IFN-γ, and TNF-α exhibited elevated levels in both AA and White American (WA) lung cancer cases. Notably, IL-10 and MCP-1 displayed significant increases specifically in AA lung cancer patients, with MCP-1 levels associated with lung adenocarcinoma cases. Conversely, WA lung cancer patients showed heightened IL-6 levels, particularly linked to lung adenocarcinoma. The combined use of specific cytokines showed promise in lung cancer diagnosis, with IL-8, IL-10, and MCP-1 achieving 76% sensitivity and 79% specificity in AAs and IL-6 and IL-8 combined offering 76% sensitivity and 74% specificity in WAs. These diagnostic biomarkers were validated in the independent cohort. The ethnicity-related cytokine biomarkers hold promise for diagnosing lung cancer in AAs and WAs, potentially addressing the observed racial disparity.

Racial differences in serum chemokines in prostate cancer patients

BACKGROUND

This study aimed to understand the differential levels of inflammatory chemokines in association with higher prostate cancer incidence and mortality in African American (AA) men than in Caucasians (CA).

METHODS

The authors used a chemokine assay to simultaneously measure 40 chemokines and cytokines levels in the serum of preoperative prostate cancer patients and healthy controls of AA and CA races. Selected chemokines (CXCL2, CXCL5, and CCL23) serum level was validated in 211 serum samples from prostate cancer patients and healthy controls. Differential expression of CXCL5 and CCL23 was analyzed using immunohistochemistry in a representative cohort of prostate tumor tissues of AA and CA races.

RESULTS

Race-specific comparisons from 211 serum samples showed significantly higher levels of CXCL2 (control: 3104.0 pg/mL vs. cancer: 2451.0 pg/mL) and CXCL5 (control: 5189.0 pg/mL vs. cancer: 5459.0 pg/mL) in AA men than in CAs (CXCL2; control: 1155.0 pg/mL vs. cancer: 889.3 pg/mL, and CXCL5; control: 1183.0 pg/mL vs. cancer: 977.5 pg/mL). CCL23 differed significantly within and between the races with a lower level in AA cancer cases (454.5 vs. 966.6 pg/mL) than healthy controls (740.5 vs. 1263.0 pg/mL). Patient age, prostate-specific antigen, or Gleason scores were not significantly associated with these chemokines. Immunostaining for CXCL5 and CCL23 in a representative cohort of archival prostate tissues displayed significantly higher CXCL5 in prostate tumors than in adjacent benign tissues, whereas CCL23 was nondetectable in most of the analyzed tumor tissues.

CONCLUSION

Lower levels of CCL23 in AA prostate cancer patient sera and tumor tissues and high CXCL2 and CXCL5 may contribute to aggressive prostate cancer, as often seen in AA men. The disproportionate levels of serum chemokines associated with race warrant further exploration to improve equitability in precision oncology to benefit prostate cancer patients.

Race-Associated Genomic Correlates of Therapeutic Response in African American Patients With Non-Small-Cell Lung Cancer

PURPOSE

African American individuals are disproportionately affected by lung cancer in terms of incidence and mortality. In oncogene-driven non-small-cell lung cancer (NSCLC), emerging evidence indicates that underlying molecular heterogeneity, which can be affected by ancestry, contributes to variable drug sensitivity and therapeutic responses. The purpose of this study was to evaluate race-associated differences in reported treatment decisions, therapeutic outcomes, and molecular features in KRAS- and EGFR-mutant NSCLC.

MATERIALS AND METHODS

This is a retrospective study using real-world clinical-genomic data from health systems in the United States to evaluate race-associated outcomes in advanced-stage KRAS- or EGFR-driven NSCLC. Our overall objectives were to evaluate race-associated therapeutic outcomes and to describe molecular features in non-Hispanic Black (NHB) and non-Hispanic White (NHW) patients with NSCLC.

RESULTS

A total of 723 NSCLC patients with KRAS and 315 patients with EGFR oncogenic mutations were evaluated. In KRAS-mutant patients, variable outcomes were observed in NHB and NHW patients on the basis of receiving chemotherapy alone or in combination with immune checkpoint inhibitors. NHB patients received treatment at significantly lower rates compared with NHW patients. In the EGFR-mutant cohort, NHB and NHW patients received EGFR-targeted agents at similar rates, and overall survival was not significantly different. Race-associated differences in molecular features included a higher frequency of TP53 comutation in KRAS-mutant NHB patients and higher prevalence of EGFR G719S subtype in NHB patients.

CONCLUSION

In a real-world cohort of patients with NSCLC, we identified race-associated differences in therapeutic outcomes and described molecular characteristics in NHB and NHW patients with NSCLC. To proactively identify patients most likely to respond to systemic therapies, a more comprehensive approach is needed to help guide therapy selection in individualized patient populations.

Impact of Race on Outcomes of Advanced Stage Non-Small Cell Lung Cancer Patients Receiving Immunotherapy

BACKGROUND

The impact of race in advanced stage non-small cell lung cancer (NSCLC) patients treated with immune checkpoint inhibitors (ICIs) is conflicting. Our study sought to examine racial disparities in time to treatment initiation (TTI), overall survival (OS), and progression-free survival (PFS) using a population that was almost equally black and white.

METHODS

This was a retrospective cohort study of stage IV NSCLC patients > 18 years receiving immunotherapy at our center between 2014 and 2021. Kaplan-Meier curves and the multivariate Cox proportional hazards model determined the predictors of OS and PFS. Analyses were undertaken using IBM PSAW (SPSS v.28).

RESULTS

Out of 194 patients who met the inclusion criteria, 42.3% were black (n = 82). In the multivariate analysis, there was no difference in PFS (HR: 0.96; 95% CI: 0.66,1.40; p = 0.846) or OS (HR: 0.99; 95% CI: 0.66, 1.48; p = 0.966). No difference in treatment selection was observed between white and black patients (p = 0.363), nor was there a difference observed in median time to overall treatment initiation (p = 0.201).

CONCLUSIONS

No difference was observed in OS and PFS in black and white patients. Black patients' reception of timelier immunotherapy was an unanticipated finding. Future studies are necessary to better understand how race impacts patient outcomes.

Correlation Between Chronic Periodontitis and Lung Cancer: A Systematic Review With Meta-Analysis

Periodontal disease is associated with many systemic diseases, such as cardiovascular diseases, atherosclerosis, diabetes mellitus, stroke, and pulmonary diseases. Interestingly, recent literature suggests that periodontal disease might be a risk factor for various cancers such as lung, colon, oesophageal, head, and neck cancers. However, the precise mechanistic link is lacking. Hence, in this meta-analysis, we aimed to investigate the correlation between periodontal disease and lung cancer in periodontally diseased patients. Data were searched for relevant studies from 2010 to 2022. We correlated periodontal disease and lung cancer based on adjusted ORs/HRs and associated CIs. I2 statistic was used to assess statistical heterogeneity. Publication bias was analyzed by visually inspecting the symmetry of the funnel plot and Egger's test. The study is registered in the International Prospective Register of Systematic Reviews (PROSPERO; registration no: CRD42023390819). A total of 194,850 participants from observational studies (two case-control studies and five cohort studies) were incorporated for the current analysis. The meta-analysis of included studies showed an overall effect size (risk ratio) of the periodontal disease group with respect to the non-periodontal disease group for lung neoplasm to be 1.41 (95% CI: 1.32-1.52). The value was more than 1, indicating that the periodontal disease group had a relatively higher lung cancer prevalence than the non-periodontal disease group. Further, the overall risk ratio was found to be statistically significant (p<0.00001). Moreover, the funnel plot suggested some degree of publication bias. Evidence in our study implicated that there is an increased risk of occurrence of lung cancer in chronic periodontitis patients.

Racial/Ethnic Differences in Traumatic Brain Injury: Pathophysiology, Outcomes, and Future Directions

Traumatic brain injury (TBI) is a major cause of death and disability in the United States, exacting a debilitating physical, social, and financial strain. Therefore, it is crucial to examine the impact of TBI on medically underserved communities in the U.S. The purpose of the current study was to review the literature on TBI for evidence of racial/ethnic differences in the U.S. Results of the review showed significant racial/ethnic disparities in TBI outcome and several notable differences in other TBI variables. American Indian/Alaska Natives have the highest rate and number of TBI-related deaths compared with all other racial/ethnic groups; Blacks/African Americans are significantly more likely to incur a TBI from violence when compared with Non-Hispanic Whites; and minorities are significantly more likely to have worse functional outcome compared with Non-Hispanic Whites, particularly among measures of community integration. We were unable to identify any studies that looked directly at underlying racial/ethnic biological variations associated with different TBI outcomes. In the absence of studies on racial/ethnic differences in TBI pathobiology, taking an indirect approach, we looked for studies examining racial/ethnic differences in oxidative stress and inflammation outside the scope of TBI as they are known to heavily influence TBI pathobiology. The literature indicates that Blacks/African Americans have greater inflammation and oxidative stress compared with Non-Hispanic Whites. We propose that future studies investigate the possibility of racial/ethnic differences in inflammation and oxidative stress within the context of TBI to determine whether there is any relationship or impact on TBI outcome.

A systematic review of genetic ancestry as a risk factor for incidence of non-small cell lung cancer in the US

Background: Non-Small Cell Lung Cancer (NSCLC), the leading cause of cancer-related death in the United States, is the most diagnosed form of lung cancer. While lung cancer incidence has steadily declined over the last decade, disparities in incidence and mortality rates persist among African American (AA), Caucasian American (CA), and Hispanic American (HA) populations. Researchers continue to explore how genetic ancestry may influence differential outcomes in lung cancer risk and development. The purpose of this evaluation is to highlight experimental research that investigates the differential impact of genetic mutations and ancestry on NSCLC incidence. Methods: This systematic review was conducted using PubMed and Google Scholar search engines. The following key search terms were used to select articles published between 2011 and 2022: "African/European/Latin American Ancestry NSCLC"; "Racial Disparities NSCLC"; "Genetic Mutations NSCLC"; "NSCLC Biomarkers"; "African Americans/Hispanic Americans/Caucasian Americans NSCLC incidence." Systematic reviews, meta-analyses, and studies outside of the US were excluded. A total of 195 articles were initially identified and after excluding 156 which did not meet eligibility criteria, 38 were included in this investigation. Results: Studies included in this analysis focused on racial/ethnic disparities in the following common genetic mutations observed in NSCLC: KRAS, EGFR, TP53, PIK3CA, ALK Translocations, ROS-1 Rearrangements, STK11, MET, and BRAF. Results across studies varied with respect to absolute differential expression. No significant differences in frequencies of specific genetic mutational profiles were noted between racial/ethnic groups. However, for HAs, lower mutational frequencies in KRAS and STK11 genes were observed. In genetic ancestry level analyses, multiple studies suggest that African ancestry is associated with a higher frequency of EGFR mutations. Conversely, Latin ancestry is associated with TP53 mutations. At the genomic level, several novel predisposing variants associated with African ancestry and increased risk of NSCLC were discovered. Family history among all racial/ethnic groups was also considered a risk factor for NSCLC. Conclusion: Results from racially and ethnically diverse studies can elucidate driving factors that may increase susceptibility and subsequent lung cancer risk across different racial/ethnic groups. Identification of biomarkers that can be used as diagnostic, prognostic, and therapeutic tools may help improve lung cancer survival among high-risk populations.

The role of smoking history in longitudinal changes in C-reactive protein between Black and White older adults in the US

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This study is the first to examine the effect of race and smoking history on changes in CRP.

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Overall, there were no significant effects of race or current cigarette smoking on CRP change.

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In NHWs only, smoking history, education, sex, and BMI were predictive of CRP.

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In NHBs only, only BMI was predictive of CRP.

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NHBs may not experience the same reductions in CRP with smoking cessation as NHWs.

Smoking cessation is associated with decreases in C-reactive protein (CRP), a biomarker of systemic inflammation and cancer risk; yet CRP levels remain higher long-term in individuals who quit vs. those who never smoked. While non-Hispanic, Black/African American (NHB) have higher levels of CRP vs. non-Hispanic, White/Caucasian (NHW) adults, the association between CRP and race has not been examined in individuals with smoking history. Utilizing longitudinal data from the Health and Retirement Study (HRS), the current study examined the effects of race and smoking history on CRP in older adults. NHB (n = 242) and NHW (n = 1529) participants completed HRS assessments in 2006, 2010, and 2014. Dried blood spots collected at each wave were assayed for CRP. Linear mixed models were used to examine the effect of race and smoking history on CRP across waves – controlling for sociodemographics, physical activity, body mass index (BMI), and current smoking. Overall, results showed no significant effects of race or current smoking on CRP; rather age, sex, education, BMI, physical activity, smoking history, and time × race predicted CRP (ps<.04). However, while age, sex, education, BMI, physical activity, and smoking history were also predictive of CRP in NHWs (ps<.04) in race-stratified models, only BMI was a significant predictor of CRP in NHBs (p=.012). BMI may be important in explaining inflammation-related disease risk in NHBs with a history of smoking. NHBs may not experience the same reductions in CRP with smoking cessation as NHWs – potentially contributing to tobacco-related health disparities.

LKB1 phosphorylation and deactivation in lung cancer by NNAL, a metabolite of tobacco-specific carcinogen, in an isomer-dependent manner

LKB1 loss of function is one key oncogenic event in lung cancer. Clinical data suggest that LKB1 loss of function is associated with patients' smoking status. The responsible ingredients and molecular mechanisms in tobacco for LKB1 loss of function, however, are not defined. In this study, we reported that NNAL, a major metabolite of a tobacco-specific carcinogen NNK, induces LKB1 phosphorylation and its loss of function via the β-AR/PKA signaling pathway in an isomer-dependent manner in human lung cancer cells. NNAL exposure also resulted in enhanced lung cancer cell migration and chemoresistance in an LKB1-dependent manner. A 120-day NNAL exposure in lung cancer cells, mimicking its chronic exposure among smokers, resulted in more prominent LKB1 phosphorylation, cell migration, and chemoresistance even in the absence of NNAL, indicating the long-lasting LKB1 loss of function although such an effect eventually disappeared after NNAL was removed for two months. These observations were confirmed in a lung cancer xenograft model. More importantly, human lung cancer tissues revealed elevated LKB1 phosphorylation in comparison to the paired normal lung tissues. These results suggest that LKB1 loss of function in human lung cancer could be extended to its phosphorylation, which may be mediated by NNAL from tobacco smoke in an isomer-dependent manner via the β-AR/PKA signaling pathway.

Potential of Inflammatory Protein Signatures for Enhanced Selection of People for Lung Cancer Screening

Randomized trials have demonstrated a substantial reduction in lung cancer (LC) mortality by screening heavy smokers with low-dose computed tomography (LDCT). The aim of this study was to assess if and to what extent blood-based inflammatory protein biomarkers might enhance selection of those at highest risk for LC screening. Ever smoking participants were chosen from 9940 participants, aged 50-75 years, who were followed up with respect to LC incidence for 17 years in a prospective population-based cohort study conducted in Saarland, Germany. Using proximity extension assay, 92 inflammation protein biomarkers were measured in baseline plasma samples of ever smoking participants, including 172 incident LC cases and 285 randomly selected participants free of LC. Smoothly clipped absolute deviation (SCAD) penalized regression with 0.632+ bootstrap for correction of overoptimism was applied to derive an inflammation protein biomarker score (INS) and a combined INS-pack-years score in a training set, and algorithms were further evaluated in an independent validation set. Furthermore, the performances of nine LC risk prediction models individually and in combination with inflammatory plasma protein biomarkers for predicting LC incidence were comparatively evaluated. The combined INS-pack-years score predicted LC incidence with area under the curves (AUCs) of 0.811 and 0.782 in the training and the validation sets, respectively. The addition of inflammatory plasma protein biomarkers to established nine LC risk models increased the AUCs up to 0.121 and 0.070 among ever smoking participants from training and validation sets, respectively. Our results suggest that inflammatory protein biomarkers may have potential to improve the selection of people for LC screening and thereby enhance screening efficiency.

Immune response and inflammation in cancer health disparities

Cancer death rates vary among population groups. Underserved populations continue to experience an excessive burden of lethal cancers that is largely explained by health-care disparities. However, the prominent role of advanced-stage disease as a driver of cancer survival disparities may indicate that some cancers are more aggressive in certain population groups than others. The tumor mutational burden can show large differences among patients with similar-stage disease but differences in race/ethnicity or residence. These dissimilarities may result from environmental or chronic inflammatory exposures, altering tumor biology and the immune response. We discuss the evidence that inflammation and immune response dissimilarities among population groups contribute to cancer disparities and how they can be targeted to reduce these disparities.

Crosstalk Between Inflammatory Signaling and Methylation in Cancer

Inflammation is an intricate immune response against infection and tissue damage. While the initial immune response is important for preventing tumorigenesis, chronic inflammation is implicated in cancer pathogenesis. It has been linked to various stages of tumor development including transformation, proliferation, angiogenesis, and metastasis. Immune cells, through the production of inflammatory mediators such as cytokines, chemokines, transforming growth factors, and adhesion molecules contribute to the survival, growth, and progression of the tumor in its microenvironment. The aberrant expression and secretion of pro-inflammatory and growth factors by the tumor cells result in the recruitment of immune cells, thus creating a mutual crosstalk. The reciprocal signaling between the tumor cells and the immune cells creates and maintains a successful tumor niche. Many inflammatory factors are regulated by epigenetic mechanisms including DNA methylation and histone modifications. In particular, DNA and histone methylation are crucial forms of transcriptional regulation and aberrant methylation has been associated with deregulated gene expression in oncogenesis. Such deregulations have been reported in both solid tumors and hematological malignancies. With technological advancements to study genome-wide epigenetic landscapes, it is now possible to identify molecular mechanisms underlying altered inflammatory profiles in cancer. In this review, we discuss the role of DNA and histone methylation in regulation of inflammatory pathways in human cancers and review the merits and challenges of targeting inflammatory mediators as well as epigenetic regulators in cancer.

Periodontal Disease and Tooth Loss Are Associated with Lung Cancer Risk

Background

The associations between periodontal disease, tooth loss, and lung cancer risk remain debatable. Therefore, the purpose of the present study is to evaluate whether periodontal disease and tooth loss are associated with lung cancer risk.

Methods

A literature search was performed for relevant studies using PubMed and Embase databases. Risk ratio (RR) with 95% confidence interval (CI) was applied as effect size to summarize the associations between periodontal disease, tooth loss, and lung cancer risk. A further dose-response analysis was also performed.

Results

A total of twelve studies comprising 263,238 participants were included. The results indicated that periodontal disease was positively associated with lung cancer risk (RR = 1.37, 95%CI = 1.16‐1.63). There was a positive association between tooth loss and lung cancer risk (RR = 1.69, 95%CI = 1.46‐1.96). Moreover, there was a significantly linear dose-response relationship between tooth loss and lung cancer risk, and every 5 increment in tooth loss was associated with 10% increased lung cancer risk. Similar results were obtained in subgroup analysis.

Conclusions

Periodontal disease and tooth loss are increased risk factors for lung cancer. Prevention and treatment of periodontal disease may be effective potential prevention strategies for lung cancer.

An overview of cancer health disparities: new approaches and insights and why they matter

Cancer health disparities remain stubbornly entrenched in the US health care system. The Affordable Care Act was legislation to target these disparities in health outcomes. Expanded access to health care, reduction in tobacco use, uptake of other preventive measures and cancer screening, and improved cancer therapies greatly reduced cancer mortality among women and men and underserved communities in this country. Yet, disparities in cancer outcomes remain. Underserved populations continue to experience an excessive cancer burden. This burden is largely explained by health care disparities, lifestyle factors, cultural barriers, and disparate exposures to carcinogens and pathogens, as exemplified by the COVID-19 epidemic. However, research also shows that comorbidities, social stress, ancestral and immunobiological factors, and the microbiome, may contribute to health disparities in cancer risk and survival. Recent studies revealed that comorbid conditions can induce an adverse tumor biology, leading to a more aggressive disease and decreased patient survival. In this review, we will discuss unanswered questions and new opportunities in cancer health disparity research related to comorbid chronic diseases, stress signaling, the immune response, and the microbiome, and what contribution these factors may have as causes of cancer health disparities.

Whole-Exome Profiling of NSCLC Among African Americans

INTRODUCTION

Lung cancer incidence is higher among African Americans (AAs) compared with European Americans (EAs) in the United States, especially among men. Although significant progress has been made profiling the genomic makeup of lung cancer in EAs, AAs continue to be underrepresented. Our objective was to chart the genome-wide landscape of somatic mutations in lung cancer tumors from AAs.

METHODS

In this study, we used the whole-exome sequencing of 82 tumor and noninvolved tissue pairs from AAs. Patients were selected from an ongoing case-control study conducted by the National Cancer Institute and the University of Maryland.

RESULTS

Among all samples, we identified 178 significantly mutated genes (p < 0.05), five of which passed the threshold for false discovery rate (p < 0.1). In lung adenocarcinoma (LUAD) tumors, mutation rates in STK11 (p = 0.05) and RB1 (p = 0.008) were significantly higher in AA LUAD tumors (25% and 13%, respectively) compared with The Cancer Genome Atlas EA samples (14% and 4%, respectively). In squamous cell carcinomas, mutation rates in STK11 (p = 0.002) were significantly higher among AA (8%) than EA tumors from The Cancer Genome Atlas (1%). Integrated somatic mutation data with CIBERSORT (Cell-type Identification By Estimating Relative Subsets Of RNA Transcripts) data analysis revealed LUAD tumors from AAs carrying STK11 mutations have decreased interferon signaling.

CONCLUSIONS

Although a considerable degree of the somatic mutation landscape is shared between EAs and AAs, discrete differences in mutation frequency in potentially important oncogenes and tumor suppressors exist. A better understanding of the molecular basis of lung cancer in AA patients and leveraging this information to guide clinical interventions may help reduce disparities.

Recurrent PTPRT/JAK2 mutations in lung adenocarcinoma among African Americans

Reducing or eliminating persistent disparities in lung cancer incidence and survival has been challenging because our current understanding of lung cancer biology is derived primarily from populations of European descent. Here we show results from a targeted sequencing panel using NCI-MD Case Control Study patient samples and reveal a significantly higher prevalence of PTPRT and JAK2 mutations in lung adenocarcinomas among African Americans compared with European Americans. This increase in mutation frequency was validated with independent WES data from the NCI-MD Case Control Study and TCGA. We find that patients carrying these mutations have a concomitant increase in IL-6/STAT3 signaling and miR-21 expression. Together, these findings suggest the identification of these potentially actionable mutations could have clinical significance for targeted therapy and the enrollment of minority populations in clinical trials.