Faculty Bibliography

Mutations in the epidermal growth factor receptor (EGFR) represent one of the most common "actionable" alterations in non-small cell lung cancer (NSCLC). Typified by high response rates to targeted therapies, EGFR tyrosine kinase inhibitors (TKI) are now established first-line treatment options and have transformed the treatment paradigm for NSCLC. With the recent breakthrough designation and approval of osimertinib, a 3rd generation EGFR TKI, available systemic and local treatment options have expanded, requiring new clinical algorithms that take into account individual patient molecular and clinical profiles. In this International Association for the Study of Lung Cancer (IASLC) commissioned consensus statement, key pathologic, diagnostic and therapeutic considerations, such as optimal choice of EGFR TKI and management of brain metastasis, are discussed. In addition, recommendations are made for clinical guidelines and research priorities, such as the role of re-biopsies and use of circulating free DNA (cfDNA) for molecular studies. With the rapid pace of progress in treating EGFR mutant NSCLC, this statement provides a state-of-the-art review of the contemporary issues in managing this unique subgroup of patients.

PURPOSE: To determine whether serum levels of High Mobility Group Box Protein-1 (HMGB1) could differentiate malignant mesothelioma (MM) patients, asbestos-exposed individuals, and unexposed controls. EXPERIMENTAL DESIGN: Hyper-acetylated and non-acetylated HMGB1 (together referred to as total HMGB1) were blindly measured in blood collected from MM patients (n=22), individuals with verified chronic asbestos exposure (n=20), patients with benign pleural effusions (n=13) or malignant pleural effusions not due to MM (n=25), and healthy controls (n=20). Blood levels of previously proposed MM biomarkers fibulin-3, mesothelin, and osteopontin were also measured in non-healthy individuals. RESULTS: HMGB1 serum levels reliably distinguished MM patients, asbestos-exposed individuals, and unexposed controls. Total HMGB1 was significantly higher in MM patients and asbestos-exposed individuals compared to healthy controls. Hyper-acetylated HMGB1 was significantly higher in MM patients compared to asbestos-exposed individuals and healthy controls, and did not vary with tumor stage. At the cut-off value of 2.00 ng/ml, the sensitivity and specificity of serum hyper-acetylated HMGB1 in differentiating MM patients from asbestos-exposed individuals and healthy controls was 100%, outperforming other previously proposed biomarkers. Combining HMGB1 and fibulin-3 provided increased sensitivity and specificity in differentiating MM patients from patients with cytologically benign or malignant non-MM pleural effusion. CONCLUSIONS: Our results are significant and clinically relevant as they provide the first biomarker of asbestos exposure and indicate that hyper-acetylated HMGB1 is an accurate biomarker to differentiate MM patients from individuals occupationally exposed to asbestos and unexposed controls. A trial to independently validate these findings will start soon.

PURPOSE: Prognostic models for pleural mesothelioma (MPM) are needed to prevent potentially futile outcomes. We combined MPM plasma biomarkers with validated clinical prognostic indices to determine whether stratification of risk for death in 194 MPM patients improved. PATIENTS AND METHODS: Individuals were recruited from three different centers: a discovery cohort (83 MPM) created by combining patients from two US centers and a separate, independent cohort from Canada (111 MPM). Univariable/multivariable analyses were performed on the initial discovery and independent cohorts separately. In multivariable analyses, prognostic factors were adjusted for the Mesothelioma EORTC Prognostic Index (PI). The prognostic significance of adding plasma biomarker data to the PI was determined using the likelihood ratio test, comparing models with and without the addition of biomarker to the clinical PI. The predictive ability of the biomarker was then assessed formally using Harrell's c-index by applying the fitted model variables of the discovery cohort to the second, independent cohort, including and not including the biomarker with the PI. RESULTS: Higher levels of osteopontin and mesothelin were individually associated with worse prognosis after adjusting for the PI. In the independent cohort, incorporating either plasma osteopontin or mesothelin into the baseline predictive PI model substantively and statistically significantly improved Harrell's c-statistic. In the final prognostic model, log-osteopontin, EORTC CPI, and hemoglobin remained as independently significant predictors, and the entire prognostic model improved the optimism-corrected Harrell's c-index significantly from 0.718 (0.67-0.77) to 0.801 (0.77-0.84). CONCLUSION: These data suggest a possible role for preoperative plasma biomarkers to improve prognostic capability of the MPM EORTC PI.

Chronic lymphocytic leukemia (CLL) is the most common human leukemia, and transgenic mouse studies indicate that activation of the T-cell leukemia/lymphoma 1 (TCL1) oncogene is a contributing event in the pathogenesis of the aggressive form of this disease. While studying the regulation ofTCL1expression, we identified the microRNA clustermiR-4521/3676and discovered that these two microRNAs are associated with tRNA sequences and that this region can produce two small RNAs, members of a recently identified class of small noncoding RNAs, tRNA-derived small RNAs (tsRNAs). We further proved thatmiR-3676andmiR-4521are tsRNAs using Northern blot analysis. We found that, likets-3676,ts-4521is down-regulated and mutated in CLL. Analysis of lung cancer samples revealed that bothts-3676andts-4521are down-regulated and mutated in patient tumor samples. Because tsRNAs are similar in nature to piRNAs [P-element-induced wimpy testis (Piwi)-interacting small RNAs], we investigated whetherts-3676andts-4521can interact with Piwi proteins and found these two tsRNAs in complexes containing Piwi-like protein 2 (PIWIL2). To determine whether other tsRNAs are involved in cancer, we generated a custom microarray chip containing 120 tsRNAs 16 bp or more in size. Microarray hybridization experiments revealed tsRNA signatures in CLL and lung cancer, indicating that, like microRNAs, tsRNAs may have an oncogenic and/or tumor-suppressor function in hematopoietic malignancies and solid tumors. Thus, our results show that tsRNAs are dysregulated in human cancer.

Lung cancer continues to be a major global health problem with more than 1.6 million new patients diagnosed each year with this disease. However, significant progress is underway in both the prevention and treatment of lung cancer. Lung cancer therapy has now emerged as a "role model" for precision cancer medicine with several important therapeutic breakthroughs occurring during 2015. These advances have occurred primarily in the immunotherapy field and in treatments directed against tumors harboring specific oncogenic drivers. Our knowledge about molecular mechanisms for oncogenic driven tumors and about resistance to targeted therapies has increased quickly over the last year. As a result, several regulatory approvals of new agents have occurred; which significantly improve survival and quality of life for lung cancer patients with advanced disease. The International Association for the Study of Lung Cancer has gathered experts in different areas of lung cancer research and management to summarize the most significant scientific advancements related to prevention and therapy of lung cancer during the last year.

Germline BAP1 mutations predispose to several cancers, in particular malignant mesothelioma. Mesothelioma is an aggressive malignancy generally associated with professional exposure to asbestos. However, to date, we found that none of the mesothelioma patients carrying germline BAP1 mutations were professionally exposed to asbestos. We hypothesized that germline BAP1 mutations might influence the asbestos-induced inflammatory response that is linked to asbestos carcinogenesis, thereby increasing the risk of developing mesothelioma after minimal exposure. Using a BAP1(+/-) mouse model, we found that, compared with their wild-type littermates, BAP1(+/-) mice exposed to low-dose asbestos fibers showed significant alterations of the peritoneal inflammatory response, including significantly higher levels of pro-tumorigenic alternatively polarized M2 macrophages, and lower levels of several chemokines and cytokines. Consistent with these data, BAP1(+/-) mice had a significantly higher incidence of mesothelioma after exposure to very low doses of asbestos, doses that rarely induced mesothelioma in wild-type mice. Our findings suggest that minimal exposure to carcinogenic fibers may significantly increase the risk of malignant mesothelioma in genetically predisposed individuals carrying germline BAP1 mutations, possibly via alterations of the inflammatory response.

BACKGROUND: Recent computed tomography (CT) screening trials showed that it is effective for early detection of lung cancer, but were plagued by high false positive rates. Additional blood biomarker tests designed to complement CT screening and reduce false positive rates are highly desirable. OBJECTIVE: Identify blood-based metabolite biomarkers for diagnosing lung cancer. MEHTODS: Serum samples from subjects participating in a CT screening trial were analyzed using untargeted GC-TOFMS and HILIC-qTOFMS-based metabolomics. Samples were acquired prior to diagnosis (pre-diagnostic, n= 17), at-diagnosis (n= 25) and post-diagnosis (n= 19) of lung cancer and from subjects with benign nodules (n= 29). RESULTS: Univariate analysis identified 40, 102 and 30 features which were significantly different between subjects with malignant (pre-, at- and post-diagnosis) solitary pulmonary nodules (SPNs) and benign SPNs, respectively. Ten metabolites were consistently different between subjects presenting malignant (pre- and at-diagnosis) or benign SPNs. Three of these 10 metabolites were phosphatidylethanolamines (PE) suggesting alterations in lipid metabolism. Accuracies of 77%, 83% and 78% in the pre-diagnosis group and 69%, 71% and 67% in the at-diagnosis group were determined for PE(34:2), PE(36:2) and PE(38:4), respectively. CONCLUSIONS: This study demonstrates evidence of early metabolic alterations that can possibly distinguish malignant from benign SPNs. Further studies in larger pools of samples are warranted.

INTRODUCTION: Surgery is the treatment of choice for early-stage lung cancer (LC). Although lobectomy (L) is the historic standard treatment, the issue of whether long-term outcomes of sublobar resection (SL) are comparable is still under debate. The objective of this study was to perform a review of the literature on 5-year survival rates after SL compared to L for patients with early-stage LC. METHODS: A priori inclusion criteria were as follows: (1) observational studies, (2) L compared to SL for early-stage LC, (3) radiographic staging by computed tomography scan, and (4) 5-year survival reported. A Medline search through January 2015 resulted in 31 studies representing 23 distinct datasets. The absolute difference in 5-year survival was calculated and plotted for each study. RESULTS: L was performed in 4564 patients and SL in 2287 patients. Of 19 studies reporting the reason for SL, 11 indicated that SL was performed because of comorbidities or impaired cardiopulmonary function. Four studies showed no difference in 5-year survival, 13 favored L, and six favored SL. One propensity score study favored L and the other favored SL. Of 20 studies reporting recurrence rate, 11 favored L and nine favored SL. CONCLUSIONS: Studies comparing 5-year survival rates of SL to L are sufficiently heterogeneous to prevent carrying out traditional meta-analysis. SL survival is often similar to L when adjustments are made for age, comorbidities, or impaired cardiopulmonary function. New approaches are needed for the comparison of L to SL.

INTRODUCTION: The reduction in lung cancer mortality associated with computed tomography (CT) screening has led to its increased use and a concomitant increase in the detection of benign pulmonary nodules. Many individuals found to have benign nodules undergo unnecessary, costly, and invasive procedures. Therefore, there is a need for companion diagnostics that stratify individuals with pulmonary nodules into high-risk or low-risk groups. Lung cancers can trigger host immune responses and elicit antibodies against tumor antigens. The identification of these autoantibodies (AAbs) and their corresponding antigens may expand our knowledge of cancer immunity, leading to early diagnosis or even benefiting immunotherapy. Previous studies were performed mostly in the context of comparing cancers and healthy (smoker) controls. We have performed one of the first studies to understand humoral immune response in patients with cancer, patients with benign nodules, and healthy smokers. METHODS: We first profiled seroreactivity to 10,000 full-length human proteins in 40 patients with early-stage lung cancer and 40 smoker controls by using nucleic acid programmable protein arrays to identify candidate cancer-specific AAbs. Enzyme-linked immunosorbent assays of promising candidates were performed on 137 patients with lung cancer and 127 smoker controls, as well as on 170 subjects with benign pulmonary nodules. RESULTS: From protein microarray screening experiments using a discovery set of 40 patients and 40 smoker controls, 17 antigens showing higher reactivity in lung cancer cases relative to the controls were subsequently selected for evaluation in a large sample set (n = 264) by using enzyme-linked immunosorbent assay. A five-AAb classifier (tetratricopeptide repeat domain 14 [TTC14], B-Raf proto-oncogene, serine/threonine kinase [BRAF], actin like 6B [ACTL6B], MORC family CW-type zinc finger 2 [MORC2], and cancer/testis antigen 1B [CTAG1B]) that can differentiate lung cancers from smoker controls with a sensitivity of 30% at 89% specificity was developed. We further tested AAb responses in subjects with CT-positive benign nodules (n = 170), and developed a five-AAb panel (keratin 8, type II, TTC14, Kruppel-like factor 8, BRAF, and tousled like kinase 1) with a sensitivity of 30% at 88% specificity. Interestingly, messenger RNA levels of six AAb targets (TTC14, BRAF, MORC family CW-type zinc finger 2, cancer/testis antigen 1B, keratin 8, type II, and tousled like kinase 1) were also found to increase in lung adenocarcinoma tissues based on The Cancer Genome Atlas data set. CONCLUSION: We discovered AAbs associated with lung adenocaricnoma that have the potential to differentiate cancer from CT-positive benign diseases. We believe that these antibodies warrant future validation using a larger sample set and/or longitudinal samples individually or as a panel. They could potentially be part of companion molecular diagnostic modalities that will benefit subjects undergoing CT screening for lung cancer.