Squamous cell lung cancer

The overarching concept guiding our work is that combinations of biomarkers and imaging characteristics will be most robust in predicting which patients with lung nodules should receive an aggressive diagnostic and/or therapeutic approach and which patients should be monitored for nodule stability over time. Our objectives are to improve two biomarker tests that already have shown significant promise-- sputum chromosomal aneusomy by fluorescence in situ hybridization (CA-FISH) and the analysis of multiple serum analytes by a highly multiplexed aptamer-based assay developed by SomaLogic, Inc.-- and then to compare test performance with predictive models based on nodule and patient characteristics. These objectives are based on two separate hypotheses: 1. The current CA-FISH assay panel can be further improved by the development of two sub-panels, one for detection of squamous cell carcinoma of the lung (SCC) and the second for the detection of adenocarcinoma of the lung (AC). 2. The current aptamer-based analysis can be further improved by developing separate assays specifically designed for the detection of AC, SCC, K-ras, and EGFR-mutated lung tumors. The assays will then be applied to sputum and blood specimens from the Pittsburgh SPORE Pittsburgh Lung Screening Study (PLuSS) and Colorado SPORE Lung Nodule cohorts, in concert with analysis of the CT characteristics of the corresponding lung nodules, including size, volume, density, location, or airway involvement, to compare test performances and to assess whether combining tests would be valuable.

Evaluating suspicious pulmonary nodules in the setting of a lung cancer diagnostic work-up is a common clinical management challenge. High resolution multi-detector computed tomography visualizes many noncalcified lesions that could represent either potentially lethal cancers or benign processes. Although the vast majority of these nodules are benign, non-neoplastic lesions, a subset will be malignant and in these cases, patients could benefit from immediate treatment. A non-invasive test that maintains a high sensitivity and specificity across the spectrum of clinical presentations of pulmonary nodules would be of tremendous clinical benefit by reducing the number unnecessary invasive procedures and minimizing the time between detection and definitive treatment. The overall goal for the proposed studies is to develop a convenient and low-cost serum test that will, either alone or in combination with clinical features, accurately classify indeterminate nodules and direct proper clinical management. Our approach to develop such a test will be to profile and identify which proteins detected in the serum at the time of the detection of these nodules were immunogenic and induced the production of circulating autoantibodies. Differences in the autoantibody profile between the malignant and non-malignant groups will then be further evaluated against additional clinical specimens from both our institution and two pre-specified collaborator institutions to identify the optimal test for this urgent clinical need. Once completed, we anticipate this test will aid clinicians in deciding the optimal treatment for patients found to have suspicious nodules and improve the current standard of care.

The development of non-invasive diagnostic tools to detect lung cancer at an early stage is the subject of active investigations because of its enormous potential impact on the number-one cause of cancer-related deaths. We have recently discovered by shotgun proteomics profiling 164 candidate biomarkers that are differentially expressed in stage 1 lung cancer tissue compared to non-malignant matched controls tissues and found in the circulation. Validation of these candidates by traditional methods using western blot or ELISA is a slow, low throughput, and expensive process. In this application, we propose to take advantage of the individual’s immune response to capture and detect autoantibodies directed against these 164 candidate protein targets identified by shotgun proteomics. To achieve this goal, we intend (1) to establish immune-based assays for the detection and quantitation  of lung cancer autoantibodies using an indirect ELISA; (2) to validate the diagnostic performance of our autoantibody signature in blood samples from individuals with early-stage lung cancer or matched nodule controls; and (3) to determine whether the diagnostic performance of our panel of autoantibody signatures augments the diagnostic accuracy of known predictive models for the evaluation of lung nodules. These studies may lead to the development and early validation of a new molecular diagnostic tool for lung cancer.

Recently, the National Lung Screening Trial reported a 20% reduction in lung cancer mortality and lung cancer chemoprevention trials targeting the arachidonic acid pathway have demonstrated decreases in lung cancer associate markers .These studies highlight possibilities for future reductions in lung cancer mortality through early detection and chemoprevention. Our group has previously identified smoking- and lung cancer-specific gene expression alterations in cytologically normal airway epithelial cells that can serve s a clinically relevant biomarker for the early detection of lung cancer. We propose to extend our studies of the field of injury by profiling  these cells from high-risk smokers with preinvasive lesions (dysplasia) and matched controls without lesions by RNA-Seq. We will characterize the molecular alterations (coding, noncoding, and novel RNA expression and alterative splicing) associated with the field of injury in premalignancy and identify whether these differences are similar in both current and former smokers. Next, we will develop molecular signatures that predict subsequent progression or regression of premalignant lesions as well as changes that occur as a result of progression or regression. Collectively, these signatures will aid in the stratification of high-risk smokers for chemoprevention trials, serve as intermediate markers of efficacy in these trials, and identify new targets for chemoprevention. Finally, we will explore whether these molecular signatures re associated with occult lung cancer or future lung cancer development in independent cohorts as common alterations may indicate early events in lung carcinogenesis and have additional utility as biomarkers in the early detection of lung cancer.

Small cell lung cancer (SCLC) exhibits aggressive clinical behavior and poor outcome and response to therapy. Moreover, there are no effective strategies for early detection of SCLC. Therefore, there is an urgent need to identify new strategies and markers for SCLC detection. We recently characterized the molecular airway field cancerization (FC) in non-small cell lung carcinoma (NSCLC) patients and identified airway profiles that varied spatially (n=1165) and with time (n=1395) following surgery. Moreover, we characterized the adjacent airway FC in NSCLC (n=1606 genes), a subset of which (n=299) significantly distinguished airways of smokers with lung cancer from those of healthy smokers and another (n=208) separated airways of different NSCLC subtypes. Although we previously showed that SCLCs and adjacent airways are characterized by higher level of allelic losses compared to those of NSCLC cases, the global airway FC in SCLC and its relevance to detection has not been explored. We hypothesize that the molecular airway FC in SCLC is different compared to that in NSCLC or benign lung disease and comprises biomarkers specific for early detection of SCLC. We will 1) perform global expression profiling of the airway FC and tumors or nodules in patients with SCLC, NSCLC, and benign disease for identification of airway markers specific to SCLC and 2) test identified airway mRNA markers for SCLC detection in bronchial and nasal compartments in patients with suspect lung cancer. We anticipate that our proposal, due to its unique resources and approaches, will identify novel markers for SCLC detection.

Lung cancer remains the leading cause of cancer death in the world for both men and women. Prevention studies have largely been ineffective. A chemoprevention trial using the prostacyclin analogue iloprost demonstrated improvement in endobronchial histology in former smokers. An ongoing trial is investigating lung cancer chemoprevention with pioglitazone, which decreases lung cancer risk in diabetics. The effects of iloprost and pioglitazone are mediated by PPARγ and its downstream targets. We hypothesize that response to iloprost and pioglitazone depends on expression of PPARγ and that measures of prostacyclin and PPARγ activity will correlate with histology. We will measure a PPARγ expression in biopsy tissues to determine if expression can predict response to iloprost. We will assess methylation and acetylation in tissues with loss of PPARγ expression, which could identify a potential role for demethylation or deacetylation agents in creating a response to chemoprevention. We will measure activity of iloprost and pioglitazone through QPCR of downstream targets. Previously generated tissues from mouse models of lung cancer chemoprevention will be used to correlate markers with human samples. miRNA have the potential to be important markers but there is little information on miRNA associated with lung cancer chemoprevention. We identify potential miRNA markers of iloprost and pioglitazone activity in dysplastic cell lines treated with iloprost or pioglitazone and in tissues from mouse models of chemoprevention. Data from this project will inform future clinical trials using iloprost and pioglitazone, improve targeted lung cancer chemoprevention, and identify relevant miRNA markers for future chemoprevention studies.

Whole genome pooled retroviral shRNA screens were performed in NSCLC cell lines A549 and NCI-H460. Out of nearly 18,000 genes, the top hit whose knockdown most reproducibly showed cytoxicity was PSMA1, a core subunit of the 20S proteasome. The combination of radiotherapy and PSMA1 knockdown significantly enhanced tumor control in a mouse xenograft model. We observed that proteasome inhibition results in increases in nuclear 1κBa, which in turn decreases NF-κB binding to the promoters of Fanconi Anemia/Homologous Recombination (HR) genes including FANCD2 and BRCA1. This reduces the expression and subsequent availability of these DNA repair proteins for recruitment to double strand breaks (DSBs) induced by radiation. These mechanistic studies provided the basis for the proposed hypothesis-driven translational research.

The central hypothesis is that high levels of HR-mediated repair of radiation-induced DNA DSBs are associated with poor tumor control, which may be improved with proteasome inhibitors. First, CT-guided fractionated radiotherapy ± bortezomib will be tested in diverse genetically engineered mouse models of NSCLC to identify mutations and other biomarkers associated with responses to radiation and/or proteasome inhibitors. Immunofluorescence and immunohistochemistry against proteins, identified in prior mechanistic studies, as well as gene expression profiling (GEP), will be performed. Then, the biomarkers will be examined in archived specimens from patients treated with radiotherapy, to assess associations with outcomes. DASL will be used to perform GEP studies using formalin-fixed, paraffin-embedded specimens. The goal will be to identify pathway-based expression signatures that predict poor outcomes with radiotherapy and improved outcomes with addition of proteasome inhibitors.