Faculty Bibliography

BAP1 mutations cause a new cancer syndrome, with a high rate of malignant mesothelioma (MM). Here, we tested the hypothesis that MM associated with germline BAP1 mutations has a better prognosis compared to sporadic MM. We compared survival among germline BAP1 mutation MM patients with that of all MM (N = 10 556) recorded in the US SEER data from 1973 to 2010. We identified 23 MM patients -11 alive- with germline BAP1 mutations and available data on survival. Ten patients had peritoneal MM, ten pleural MM, and three MM in both locations. Thirteen patients had one or more malignancies in addition to MM. Actuarial median survival for the MM patients with germline BAP1 mutations was five years, as compared with less than one year for the median survival in the US SEER MM group. Five-year survival was 47%, 95%CI [24-67%], as compared with 6.7% [6.2-7.3%] in the control SEER group. Analysis of the pooled cohort of germline BAP1 mutation MM showed that patients with peritoneal MM (median survival of 10 years, P=0.0571), or with a second malignancy in addition to MM (median survival of 10 years, P=0.0716), survived for a longer time compared to patients who only had pleural MM, or MM patients without a second malignancy, respectively. In conclusion, we found that MM patients with germline BAP1 mutations have an overall seven-fold increased long-term survival, independently of sex and age. Appropriate genetic counseling and clinical management should be considered for MM patients who are also BAP1 mutation carriers.

BACKGROUND: Breath volatile organic compounds (VOCs) have been reported as biomarkers of lung cancer, but it is not known if biomarkers identified in one group can identify disease in a separate independent cohort. Also, it is not known if combining breath biomarkers with chest CT has the potential to improve the sensitivity and specificity of lung cancer screening. METHODS: Model-building phase (unblinded): Breath VOCs were analyzed with gas chromatography mass spectrometry in 82 asymptomatic smokers having screening chest CT, 84 symptomatic high-risk subjects with a tissue diagnosis, 100 without a tissue diagnosis, and 35 healthy subjects. Multiple Monte Carlo simulations identified breath VOC mass ions with greater than random diagnostic accuracy for lung cancer, and these were combined in a multivariate predictive algorithm. Model-testing phase (blinded validation): We analyzed breath VOCs in an independent cohort of similar subjects (n = 70, 51, 75 and 19 respectively). The algorithm predicted discriminant function (DF) values in blinded replicate breath VOC samples analyzed independently at two laboratories (A and B). Outcome modeling: We modeled the expected effects of combining breath biomarkers with chest CT on the sensitivity and specificity of lung cancer screening. RESULTS: Unblinded model-building phase. The algorithm identified lung cancer with sensitivity 74.0%, specificity 70.7% and C-statistic 0.78. Blinded model-testing phase: The algorithm identified lung cancer at Laboratory A with sensitivity 68.0%, specificity 68.4%, C-statistic 0.71; and at Laboratory B with sensitivity 70.1%, specificity 68.0%, C-statistic 0.70, with linear correlation between replicates (r = 0.88). In a projected outcome model, breath biomarkers increased the sensitivity, specificity, and positive and negative predictive values of chest CT for lung cancer when the tests were combined in series or parallel. CONCLUSIONS: Breath VOC mass ion biomarkers identified lung cancer in a separate independent cohort, in a blinded replicated study. Combining breath biomarkers with chest CT could potentially improve the sensitivity and specificity of lung cancer screening. TRIAL REGISTRATION: ClinicalTrials.gov NCT00639067.

Field of cancerization in the airway epithelium has been increasingly examined to understand early pathogenesis of non-small cell lung cancer. However, the extent of field of cancerization throughout the lung airways is unclear. Here we sought to determine the differential gene and microRNA expressions associated with field of cancerization in the peripheral airway epithelial cells of patients with lung adenocarcinoma. We obtained peripheral airway brushings from smoker controls (n=13) and from the lung contralateral to the tumor in cancer patients (n=17). We performed gene and microRNA expression profiling on these peripheral airway epithelial cells using Affymetrix GeneChip and TaqMan Array. Integrated gene and microRNA analysis was performed to identify significant molecular pathways. We identified 26 mRNAs and 5 miRNAs that were significantly (FDR <0.1) up-regulated and 38 mRNAs and 12 miRNAs that were significantly down-regulated in the cancer patients when compared to smoker controls. Functional analysis identified differential transcriptomic expressions related to tumorigenesis. Integration of miRNA-mRNA data into interaction network analysis showed modulation of the extracellular signal-regulated kinase/mitogen-activated protein kinase (ERK/MAPK) pathway in the contralateral lung field of cancerization. In conclusion, patients with lung adenocarcinoma have tumor related molecules and pathways in histologically normal appearing peripheral airway epithelial cells, a substantial distance from the tumor itself. This finding can potentially provide new biomarkers for early detection of lung cancer and novel therapeutic targets.

BACKGROUND: Support for early detection of lung cancer has emerged from the National Lung Screening Trial (NLST), in which low-dose computed tomography (LDCT) screening reduced lung cancer mortality by 20 % relative to chest x-ray. The US Preventive Services Task Force (USPSTF) recently recommended annual screening for the high-risk population, concluding that the benefits (life years gained) outweighed harms (false positive findings, abortive biopsy/surgery, radiation exposure). In making their recommendation, the USPSTF noted that the moderate net benefit of screening was dependent on the resolution of most false-positive results without invasive procedures. Circulating biomarkers may serve as a valuable adjunctive tool to imaging. RESULTS: We developed a broad-based proteomics discovery program, integrating liquid chromatography/mass spectrometry (LC/MS) analyses of freshly resected lung tumor specimens (n = 13), lung cancer cell lines (n = 17), and conditioned media collected from tumor cell lines (n = 7). To enrich for biomarkers likely to be found at elevated levels in the peripheral circulation of lung cancer patients, proteins were prioritized based on predicted subcellular localization (secreted, cell-membrane associated) and differential expression in disease samples. 179 candidate biomarkers were identified. Several markers selected for further validation showed elevated levels in serum collected from subjects with stage I NSCLC (n = 94), relative to healthy smoker controls (n = 189). An 8-marker model was developed (TFPI, MDK, OPN, MMP2, TIMP1, CEA, CYFRA 21-1, SCC) which accurately distinguished subjects with lung cancer (n = 50) from high risk smokers (n = 50) in an independent validation study (AUC = 0.775). CONCLUSIONS: Integrating biomarker discovery from multiple sample types (fresh tissue, cell lines and conditioned medium) has resulted in a diverse repertoire of candidate biomarkers. This unique collection of biomarkers may have clinical utility in lung cancer detection and diagnoses.

Malignant mesothelioma (MM) is a fatal disease in dire need of therapy. The role of inflammasomes in cancer is not very well studied, however, literature supports both pro-and anti-tumorigenic effects of inflammasomes on cancer depending upon the type of cancer. Asbestos is a causative agent for MM and we have shown before that it causes inflammasome priming and activation in mesothelial cells. MM tumor cells/tissues showed decreased levels of inflammasome components like NLRP3 and caspase-1 as compared to human mesothelial cells or normal tissue counterpart of tumor. Based on our preliminary findings we hypothesized that treatment of MMs with chemotherapeutic drugs may elevate the levels of NLRP3 and caspase-1 resulting in increased cell death by pyroptosis while increasing the levels of IL-1beta and other pro-inflammatory molecules. Therefore, a combined strategy of chemotherapeutic drug and IL-1R antagonist may play a beneficial role in MM therapy. To test our hypothesis we used two human MM tumor cell lines (Hmeso, H2373) and two chemotherapeutic drugs (doxorubicin, cisplatin). Through a series of experiments we showed that both chemotherapeutic drugs caused increases in NLRP3 levels, caspase-1 activation, pyroptosis and pro-inflammatory molecules released from MM cells. In vivo studies using SCID mice and Hmeso cells showed that tumors were smaller in combined treatment group of cisplatin and IL-1R antagonist (Anakinra) as compared to cisplatin alone or untreated control groups. Taken together our study suggests that chemotherapeutic drugs in combination with IL-1R antagonist may have a beneficial role in MM treatment.