Hasmeena Kathuria

Transcriptional repression of Caveolin-1 (CAV1) gene expression by GATA-6 in bladder smooth muscle hypertrophy in mice and human beings.

Hypertrophy occurs in urinary bladder wall smooth muscle (BSM) in men with partial bladder outlet obstruction (PBOO) caused by benign prostatic hyperplasia (BPH) and in animal models of PBOO. Hypertrophied BSM from the rabbit model exhibits down-regulation of caveolin-1, a structural and functional protein of caveolae that function as signaling platforms to mediate interaction between receptor proteins and adaptor and effector molecules to regulate signal generation, amplification, and diversification. Caveolin-1 expression is diminished in PBOO-induced BSM hypertrophy in mice and in men with BPH. The proximal promoter of the human and mouse caveolin-1 (CAV1) gene was characterized, and it was observed that the transcription factor GATA-6 binds this promoter, causing reduced expression of caveolin-1. Furthermore, caveolin-1 expression levels inversely correlate with the abundance of GATA-6 in BSM hypertrophy in mice and human beings. Silencing of GATA6 gene expression up-regulates caveolin-1 expression, whereas overexpression of GATA-6 protein sustains the transcriptional repression of caveolin-1 in bladder smooth muscle cells. Together, these data suggest that GATA-6 acts as a transcriptional repressor of CAV1 gene expression in PBOO-induced BSM hypertrophy in men and mice. GATA-6-induced transcriptional repression represents a new regulatory mechanism of CAV1 gene expression in pathologic BSM, and may serve as a target for new therapy for BPH-induced bladder dysfunction in aging men.

Updates and Controversies in the Rapidly Evolving Field of Lung Cancer Screening, Early Detection, and Chemoprevention

Lung cancer remains the leading cause of cancer-related death in the United States. Cigarette smoking is a well-recognized risk factor for lung cancer, and a sustained elevation of lung cancer risk persists even after smoking cessation. Despite identifiable risk factors, there has been minimal improvement in mortality for patients with lung cancer primarily stemming from diagnosis at a late stage when there are few effective therapeutic options. Early detection of lung cancer and effective screening of high-risk individuals may help improve lung cancer mortality. While low dose computerized tomography (LDCT) screening of high risk smokers has been shown to reduce lung cancer mortality, the high rates of false positives and potential for over-diagnosis have raised questions on how to best implement lung cancer screening. The rapidly evolving field of lung cancer screening and early-detection biomarkers may ultimately improve the ability to diagnose lung cancer in its early stages, identify smokers at highest-risk for this disease, and target chemoprevention strategies. This review aims to provide an overview of the opportunities and challenges related to lung cancer screening, the field of biomarker development for early lung cancer detection, and the future of lung cancer chemoprevention.

ERM is expressed by alveolar epithelial cells in adult mouse lung and regulates caveolin‐1 transcription in mouse lung epithelial cell lines

We previously identified an Ets cis‐element in the mouse caveolin‐1 promoter that is selectively activated in lung epithelial (E10), but not lung endothelial murine lung endothelial cell line (MFLM‐4), cell lines and therefore appears important for differential, cell‐specific caveolin‐1 transcription. In the present study, we demonstrate that immunostaining of adult mouse lung detects the ETS protein Ets‐related molecule (ERM PEA3) in distal lung epithelium in alveolar type I and II cells, but not in bronchial epithelium or lung endothelial cells. We tested ERM and polyomavirus enhancer activator 3 (PEA3) for their ability to increase endogenous caveolin‐1 transcripts and to activate caveolin‐1 promoter fragments containing the −865 Ets cis‐element. Chromatin immunoprecipitation (ChIP) assays show that both ERM and PEA3 bind to the caveolin‐1 promoter in murine E10, but not MFLM‐4, cells. Normalized luciferase activities show that only ERM activates the caveolin‐1 promoter in E10 cells, but neither protein enhances promoter activity in MFLM‐4 cells. Mutation of the Ets site blocks ERM‐mediated promoter activation in E10 cells. Furthermore, overexpression of ERM increases the cellular content of caveolin‐1 mRNA and protein, in E10, but not MFLM‐4, cells. The effects of PEA3 on the cellular content of endogenous caveolin‐1 expression are variable. These results demonstrate that ERM is involved in caveolin‐1 regulation in a murine lung epithelial, but not lung endothelial cell line. We conclude that transcriptional regulation of caveolin‐1 differs markedly between lung epithelial and endothelial cell lines, perhaps explaining why the onset of caveolin‐1 expression differs in epithelial and endothelial cells during lung development. J. Cell. Biochem. 102: 13–27, 2007.

Initial surgical experience following implementation of lung cancer screening at an urban safety net hospital

Background: Safety net hospitals provide care mostly to low‐income, uninsured, and vulnerable populations, in whom delays in cancer screening are established barriers. Socioeconomic barriers might pose important challenges to the success of a lung cancer screening program at a safety net hospital. We aimed to determine screening follow‐up compliance, rates of diagnostic and treatment procedures, and the rate of cancer diagnosis in patients classified as category 4 by the Lung CT Screening Reporting and Data System (Lung‐RADS 4). Methods: We conducted a retrospective review of all patients enrolled in our multidisciplinary lung cancer screening program between March 2015 and July 2016. Demographics, smoking status, Lung‐RADS score, and number of diagnostic and therapeutic interventions and cancer diagnoses were captured. Results: A total of 554 patients were screened over a 16‐month period. The mean patient age was 63 years (range, 47–85 years), and 60% were male. The majority (92%; 512 of 554) were classified as Lung‐RADS 1 to 3, and 8% (42 of 554) were classified as Lung‐RADS 4. Among the Lung‐RADS 4 patients, 98% (41 of 42) completed their recommended follow‐up; 29% (12 of 42) underwent a diagnostic procedure, for an overall diagnostic intervention rate of 2% (12 of 554). Eleven of these 12 patients had cancer, and 1 patient had sarcoidosis. The overall rate of surgical resection was 0.9% (5 of 554), and the rate of diagnostic intervention for noncancer diagnosis was 0.1% (1 of 554). Conclusions: Implementation of a multidisciplinary lung cancer screening program at a safety net hospital is feasible. Compliance with follow‐up and interventional recommendations in Lung‐RADS 4 patients was high despite anticipated social challenges. Overall diagnostic and surgical resection rates and interventions for noncancer diagnosis were low in our initial experience.

Patient and Clinician Perspectives on Shared Decision-making in Early Adopting Lung Cancer Screening Programs: a Qualitative Study

ABSTRACTBackgroundGuidelines recommend, and Medicare requires, shared decision-making between patients and clinicians before referring individuals at high risk of lung cancer for chest CT screening. However, little is known about the extent to which shared decision-making about lung cancer screening is achieved in real-world settings.ObjectiveTo characterize patient and clinician impressions of early experiences with communication and decision-making about lung cancer screening and perceived barriers to achieving shared decision-making.DesignQualitative study entailing semi-structured interviews and focus groups.ParticipantsWe enrolled 36 clinicians who refer patients for lung cancer screening and 49 patients who had undergone lung cancer screening in the prior year. Participants were recruited from lung cancer screening programs at four hospitals (three Veterans Health Administration, one urban safety net).ApproachUsing content analysis, we analyzed transcripts to characterize communication and decision-making about lung cancer screening. Our analysis focused on the recommended components of shared decision-making (information sharing, deliberation, and decision aid use) and barriers to achieving shared decision-making.Key ResultsClinicians varied in the information shared with patients, and did not consistently incorporate decision aids. Clinicians believed they explained the rationale and gave some (often purposely limited) information about the trade-offs of lung cancer screening. By contrast, some patients reported receiving little information about screening or its trade-offs and did not realize the CT was intended as a screening test for lung cancer. Clinicians and patients alike did not perceive that significant deliberation typically occurred. Clinicians perceived insufficient time, competing priorities, difficulty accessing decision aids, limited patient comprehension, and anticipated patient emotions as barriers to realizing shared decision-making.ConclusionsDue to multiple perceived barriers, patient-clinician conversations about lung cancer screening may fall short of guideline-recommended shared decision-making supported by a decision aid. Consequently, patients may be left uncertain about lung cancer screening’s rationale, trade-offs, and process.

A Call to Formalize Training in Tobacco Dependence Treatment for Pulmonologists.

Cigarette smoking is the leading cause of preventable death in North America. We know that time spent on smoking cessation counseling and physician-delivered advice correlates to patient abstinence (1), making it incumbent on physicians to help patients quit. Fortunately, there are evidence-based treatments to help patients quit smoking. Tobacco dependence treatment options range from pharmacotherapy (including nicotine replacement therapies) to behavioral counseling (2). The U.S. Preventive Services Task Force recommends that clinicians ask all adults about tobacco use, advise them to stop, and provide behavioral interventions and pharmacotherapy approved by the U.S. Food and Drug Administration for cessation to those adults who use tobacco (A-level recommendation) (3). However, use of these interventions is neither intuitive nor commonplace. Despite the fact that all medical students receive rudimentary training in tobacco dependence treatment (typically about 4 hours total), clinician knowledge gaps are common, and implementation is poor (4). For example, the U.S. Public Health Service guidelines recommend practice of the 5As as the primary approach to smoking cessation: (1) ask about smoking, (2) advise to quit, (3) assess readiness to quit, (4) assist in connecting to tobacco treatment, and (5) arrange followup to review progress toward quitting (1). Nevertheless, in the United States, only 20.9% of smokers receive counseling, and 7.6% receive cessation medications (5). We believe this barrier to providing effective treatment for tobacco dependence is rooted in the lack of appropriate training. The recent Centers for Medicare & Medicaid Services requirement to integrate smoking cessation with lung cancer screening (6) may serve as a catalyst to improve the rates of tobacco dependence treatment among current smokers undergoing screening. Although the National Lung Screening Trial demonstrated low-dose computed tomography screening as a powerful intervention through which lung cancer mortality can be mitigated, the role of smoking cessation cannot be understated, as it is far more effective than screening to reduce smokers’ risk for lung cancer death (7). Indeed, integrating effective tobacco treatment into the low-dose computed tomography screening process is critical, as some smokers who undergo screening may believe there is little urgency to quit smoking (8). Yet, even in the context of lung cancer screening, only about half of current smokers received assistance to quit, and only 10.6% received the full U.S. Public Health Service guideline-recommended 5As protocol (9). The anticipated widespread implementation of low-dose computed tomography screening in the United States has prompted a call for additional subspecialization of pulmonologists for the practice of lung cancer-specific medicine, which would include smoking cessation counseling as a training competency (10). Although we wholeheartedly agree with the spirit of these recommendations, we believe all pulmonologists should be well versed in effective treatment of tobacco dependence, thus allowing us to leverage opportunities to reach smokers in multiple clinical contexts. Although all physicians could benefit from increased training in tobacco dependence treatment, pulmonologists represent an obvious target with which to start. Pulmonary medicine has been significantly affected by the toll smoking has taken on the public’s health. Present-day pulmonary clinics are awash with patients afflicted by smoking-related disease, and the need to care for a high volume of such patients is anticipated to persist for many years to come (11). Pulmonologists have multiple opportunities to capitalize on the “teachable moments” in our daily practice, when smokers may be acutely aware of the consequences of smoking and, thus, more receptive to cessation interventions. These teachable moments include not only lung cancer screening but also delivery of pulmonary function test results, when telling smokers their “spirometric lung age” has been shown to increase smoking quit rates (12). Taking advantage of these teachable moments is critical, as treating tobacco dependence improves mortality more than the limited armament of inhaled therapies available to treat smoking-related lung diseases (13). Yet despite the clear need and opportunity for pulmonologists to promote

NKX2-1-AS1 negatively regulates CD274/PD-L1, cell-cell interaction genes, and limits human lung carcinoma cell migration.

The function of most long noncoding RNAs (lncRNAs) is unknown. However, recent studies reveal important roles of lncRNAs in regulating cancer-related pathways. Human antisense lncRNA-NKX2-1-AS1 partially overlaps the NKX2-1/TTF1 gene within chromosomal region 14q13.3. Amplification of this region and/or differential expression of genes therein are associated with cancer progression. Herein we show higher levels of NKX2-AS1 and NKX2-1 in lung adenocarcinomas relative to non-tumor controls but no correlation between NKX2-1-AS1 and NKX2-1 levels across specimens, or with amplification of the 14q13.3 region, suggesting that NKX2-1-AS1 and NKX2-1 are independently regulated. Loss-and-gain of function experiments showed that NKX2-1-AS1 does not regulate NKX2-1 expression, or nearby genes, but controls genes in trans. Genes up-regulated by NKX2-1-AS1-knockdown belong to cell adhesion and PD-L1/PD-1 checkpoint pathways. NKX2-1-AS1 negatively regulates endogenous CD274/PD-L1, a known target of NKX2-1, and the transcriptional activity of -1kb-CD274 promoter-reporter construct. Furthermore, NKX2-1-AS1 interferes with NKX2-1 protein binding to the CD274-promoter, likely by NKX2-1 protein-NKX2-1-AS1 interactions. Finally, NKX2-1-AS1 negatively regulates cell migration and wound healing, but not proliferation or apoptosis. These findings support potential roles of NKX2-1-AS1 in limiting motility and immune system evasion of lung carcinoma cells, highlighting a novel mechanism that may influence tumorigenic capabilities of lung epithelial cells.

Chapter 9 – Lung Cancer

This review summarizes how gene expression profiling is leading to new approaches in lung cancer screening, classification, diagnosis, and treatment. The early diagnosis/screening of lung cancer section summarizes the current studies that use genomic profiling to identify the subset of smokers who are at high risk for developing lung cancer. The classification and prognosis section describes how genomic expression profiling of lung cancer has identified prognostic genes, thus potentially identifying patients who would benefit from improved diagnostic and treatment options. The pathogenesis and treatment of lung cancer section describes how genomics has advanced our ability to predict dysregulation of oncogenic pathways in lung cancer, thus potentially offering an opportunity for developing new pathway-specific therapeutics.

Stakeholder Research Priorities for Smoking Cessation Interventions within Lung Cancer Screening Programs. An Official American Thoracic Society Research Statement

Rationale: Smoking cessation counseling in conjunction with low‐dose computed tomography (LDCT) lung cancer screening is recommended in multiple clinical practice guidelines. The best approach for integrating effective smoking cessation interventions within this setting is unknown. Objectives: To summarize evidence, identify research gaps, prioritize topics for future research, and propose standardized tools for use in conducting research on smoking cessation interventions within the LDCT lung cancer screening setting. Methods: The American Thoracic Society convened a multistakeholder committee with expertise in tobacco dependence treatment and/or LDCT screening. During an in‐person meeting, evidence was reviewed, research gaps were identified, and key questions were generated for each of three research domains: (1) target population to study; (2) adaptation, development, and testing of interventions; and (3) implementation of interventions with demonstrated efficacy. We also identified standardized measures for use in conducting this research. A larger stakeholder panel then ranked research questions by perceived importance in an online survey. Final prioritization was generated hierarchically on the basis of average rank assigned. Results: There was little consensus on which questions within the population domain were of highest priority. Within the intervention domain, research to evaluate the effectiveness in the lung cancer screening setting of evidence‐based smoking cessation interventions shown to be effective in other contexts was ranked highest. In the implementation domain, stakeholders prioritized understanding strategies to identify and overcome barriers to integrating smoking cessation in lung cancer screening settings. Conclusions: This statement offers an agenda to stimulate research surrounding the integration and implementation of smoking cessation interventions with LDCT lung cancer screening.

Genomics in the Diagnosis and Management of Lung Cancer

Publisher Summary This chapter summarizes the progress made in understanding the molecular mechanisms and pathogenesis of lung cancer, and describes how gene expression profiling on human lung cancer, airway, and peripheral blood specimens is leading to new approaches in lung cancer screening, classification, diagnosis, prognosis, and treatment. The focus is on genomic studies of lung cancer and the findings of methylation and microRNA (miRNA) arrays in lung tumorigenesis. Hereditary factors explain susceptibility to the carcinogenic effects of smoking. Current studies use genomic profiling to identify the subset of smokers who are at high risk for developing lung cancer and highlights the importance of developing biomarkers and chemoprevention strategies aimed at high-risk current or former smokers. Gene expression profiling, combined with genetics, clinical information, proteomics, and imaging studies, can be applied to developing tools for risk-assessment, early diagnosis, and new approaches for individualized treatment. With stronger working relationships and collaborations between bench scientists and their clinical counterparts, and establishment of large databases with standardized methods for data collection and analyses, modern genomic technology promises continued improvement in diagnostic and therapeutic options for lung cancer patients.