Lung cancer (LC) is the leading cause of cancer death in the US, claiming over 160,000 lives annually. Although CT screening has been shown to be efficacious in reducing mortality, the limited access to screening programs among high-risk individuals and the high number of false positives contribute to low survival rates and increased healthcare costs. As a result, there is an urgent need for preventative therapeutics and novel interception biomarkers that would enhance current methods for detection of early-stage LC. This thesis addresses this challenge by examining the hypothesis that transcriptomic changes preceding the onset of LC can be identified by studying bronchial premalignant lesions (PMLs) and the normal-appearing airway epithelial cells altered in their presence (i.e., the PML-associated airway field of injury). PMLs are the presumed precursors of lung squamous cell carcinoma (SCC) whose presence indicates an increased risk of developing SCC and other subtypes of LC. Here, I leverage high-throughput mRNA and miRNA sequencing data from bronchial brushings and lesion biopsies to develop biomarkers of PML presence and progression, and to understand regulatory mechanisms driving early carcinogenesis. First, I utilized mRNA sequencing data from normal-appearing airway brushings to build a biomarker predictive of PML presence. After verifying the power of the 200-gene biomarker to detect the presence of PMLs, I evaluated its capacity to predict PML progression and detect presence of LC (Aim 1). Next, I identified likely regulatory mechanisms associated with PML severity and progression, by evaluating miRNA expression and gene coexpression modules containing their targets in bronchial lesion biopsies (Aim2). Lastly, I investigated the preservation of the PML-associated miRNAs and gene modules in the airway field of injury, highlighting an emergent link between the airway field and the PMLs (Aim 3). Overall, this thesis suggests a multi-faceted utility of PML-associated genomic signatures as markers for stratification of high-risk smokers in chemoprevention trials, markers for early detection of lung cancer, and novel chemopreventive targets, and yields valuable insights into early lung carcinogenesis by characterizing mRNA and miRNA expression alterations that contribute to premalignant disease progression towards LC. / 2020-01-25

Development of tyrosine kinase inhibitors (TKIs) against oncogenic drivers has significantly improved survival of patients with oncogene-mutated non-small cell lung cancer (NSCLC). However, acquired resistance to TKIs emerges over time in essentially all patients who initially respond. Recent evidence suggests that drug-tolerant persister (DTP) cells, which survive and adapt to targeted therapies during an early phase of treatment, play an important role in the emergence of drug resistance. A previous study reported that cluster of differentiation 74 (CD74) expression is upregulated in epidermal growth factor receptor (EGFR)-mutated lung cancer after treatment with EGFR-TKIs and that CD74 can be one of the DTP cell markers. However, both the mechanism underlying CD74 expression and the role of CD74 in DTP cells remain unclear. In the current study, an attempt was made to identify the mechanism using cell culture systems and transgenic mouse models. The results confirmed CD74 upregulation at the messenger RNA (mRNA) level after treatments with TKIs in various oncogene-mutated cell lines, including those with EGFR mutations, ROS1 fusions, and ALK fusions. The class II transactivator (CIITA), upstream of CD74, and tumor necrosis factor (TNF)-α expression were induced by treatments with TKIs in tumor cells, leading to an increase in CD74 expression. In addition, the results showed that treatments with TKIs enhance the autocrine secretion of macrophage migration inhibitory factor (MIF), a ligand of CD74, from tumor cells. This implied that autocrine stimulation of CD74 signaling blocks apoptosis and causes emergence of DTP cells. To examine whether CD74 plays an important role in the emergence of resistance to TKIs in vivo, experiments were completed in which lung-specific EGFR-L858R-T790M transgenic mice were crossed with Cd74 knockout mice. The results showed that complete deletion of CD74 overcomes or delays resistance to TKIs. Taken together, the results of this study suggest that the MIF-CD74 axis can be a novel target to overcome resistance in driver-mutated NSCLC. / 2026-02-28T00:00:00Z

There is a vast diversity in tetrapod lung branching morphology. Phylogenetically, much of the pulmonary diversity among vertebrates appears to arise from the way epithelial tubes branch or form saccular (cyst) structures. Fgf10 activity has been shown to play a critical role in regulating branch versus cyst morphology. We hypothesize that the species-specific differences in lung morphology may be primarily due to species-specific differences in Fgf10 expression. To test this hypothesis, we have performed bioinformatic analyses on the Fgf10 locus and have identified a conserved 11 kb noncoding region that potentially contains the Fgf10 lung enhancer. We are taking a large DNA sequence upstream of the Fgf10 gene of the American Alligator and swapping it into the orthologous locus in the genome of chicken primordial germ cells (cPGCs). We are accomplishing these swaps by using a combination of homology directed repair (HDR) and recombinase mediated cassette exchange (RMCE) in cPGCs. These edited cell lines can be used to generate germline chimeric chickens capable of producing offspring that putatively drive Fgf10 expression in the lung under control of regulatory sequences from various other reptiles. We have also generated a cPGC line where, through RMCE, we can easily target any enhancer from any organism to drive a GFP reporter as a means to test the temporal and spatial regulatory characteristics of these enhancers. This work is funded through a BYU Turkey Vaccine Grant and a Skaggs Mentoring Grant.

京都大学 / 新制・課程博士 / 博士(医学) / 甲第24186号 / 医博第4880号 / 新制||医||1060(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 中山 健夫, 教授 平井 豊博, 教授 中本 裕士 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

Robotic-assisted segmentectomy is a pulmonary resection procedure that is emerging as an alternative to lobectomy for the treatment of early-stage lung cancer tumours less than 2 cm in maximal diameter. Segmentectomy offers better lung function after surgery by only removing a few segments of the lobe that contain the tumour, and sparing remaining healthy lung tissue. As tumours are being more frequently detected in their early-stages, segmentectomy has gained considerable attention for its potential as a primary treatment option for suspected nodules less than 3 cm in maximal diameter. However, there is a reluctance in adopting segmentectomy due to technical challenges while performing the operation, and the lack of high-quality prospective data compared to lobectomy, which is the current standard of care. From a technical standpoint, segmentectomy is difficult to perform because the pulmonary lines that separate segments, or intersegmental planes, are invisible. This poses a challenge for the operating surgeon in determining where to resect the lung tissue to obtain adequate margin distance from the tumour. Near-infrared mapping (NIF) with indocyanine green dye (ICG) is a recent advancement in robotic-assisted segmentectomy that provides a complete delineation of the intersegmental plane. Previous work at our center has also shown that this technique was associated with an increase in the oncological margin distance compared to the surgeons’ initially estimated resection line. Given that segmentectomy is associated with a learning curve, we evaluated whether this was observed due to our early experience in robotic-assisted segmentectomy, and hypothesized that the added benefit of ICG would diminish as more cases were performed. In Chapter 2, we used a temporal analysis to monitor surgeon experience over time, and found that the clinical utility of NIF mapping diminished after approximately 42 cases with ICG, and the surgeon began to identify the location of the intersegmental plane more accurately and consistently without ICG injection since. The second barrier in the adoption of segmentectomy is the lack of high quality-prospective data. Current evidence pertaining to the effectiveness of segmentectomy in terms of cancer-related outcomes is inconclusive and difficult to generalize to the current lung cancer population. In Chapter 3, we performed a secondary analysis of a prospectively collected database of participants who underwent robotic-assisted segmentectomy or lobectomy for tumours less than 3 cm. The oncological efficacy of segmentectomy can be evaluated by the measuring the number of lymph node stations sampled intraoperatively and rates of nodal upstaging, and comparing these outcomes to pulmonary lobectomy. These are important surrogate outcomes that can be readily evaluated, and have been shown to predict overall survival after lung resection. We observed that these outcomes, including overall survival, were similar between patients who underwent segmentectomy and lobectomy for tumours less than 3 cm. While these findings were consistent for patients that underwent segmentectomy for tumours between 2 and 3 cm, recurrence-free survival was found to be significantly lower after segmentectomy compared to lobectomy. In conclusion, the clinical utility of near-infrared mapping diminishes over time, which is indicative of an improved ability to perform robotic-assisted segmentectomy as more cases were attempted. Second, adequate lymph node evaluation can be expected after segmentectomy, reducing the likelihood of missing positive lymph nodes. Although patients who underwent segmentectomy for tumours greater than 2 cm may be at a greater risk of experiencing recurrence compared to lobectomy, this population did not experience any reductions in overall survival. / Thesis / Master of Health Sciences (MSc)

<p> Using maps, correlation and multiple regression, an ecologic analysis was performed to examine the geographic distribution of cancer incidence in ontario with respect to selected ethnic, socio-economic and environmental characteristics for the 10 year period, 1976-1985. Two of the most common causes of cancer deaths, stomach and lung, were studied for each sex separately. The unit of analysis consisted of census divisions. The information used for the cancer were standardized incidence rates from the Ontario cancer Registry. The data for the ecologic variables was obtained from the 1981 Census of Canada. Two of the ecologic variables, education and income (low and median) were used to account for the effects of smoking. </p> <p> Correlation co-efficients were significant for both sites of cancer for males and females for % urban and population density revealing the possibility of a positive relationship with cancer incidence and environmental characteristics. Ethnicity was strongly related to male and female stomach cancer. </p> <p> Significant regression models were obtained for each of the cancer sites using a stepwise procedure with backward elimination. For each of the "best fit" equations, median income and education were included to control for smoking effects. Population density was significant in all equations at the 0.05 level. The percentage urban was significant for all except female stomach cancer. Manufacturing had a negative significant relationship for all cancer sites (male and female). </p> <p> Also included in the study were descriptive statistics and cancer maps to determine the strongest cancer distributions in Ontario. For each site, northern Ontario contained the highest rates. In southern Ontario, urban areas such as Hamilton-Wentworth, and Toronto-York had high rates for all cancers (except Hamilton-Wentworth for male lung cancer). </p> / Thesis / Bachelor of Arts (BA)

Image-guided radiation therapy (IGRT) provides accurate and precise tumour targeting. To ensure adequate coverage in IGRT, a planning target volume (PTV) margin is added around the target to account for treatment uncertainties. Treatment plans are designed to deliver a high percentage of the prescription dose to the PTV; thus, portions of healthy tissue are also subjected to high radiation dose. IGRT employs dedicated devices that enable visual assessment of some treatment uncertainties, such as variations in patient set-up. Safe and effective IGRT delivery requires adherence to disease site-specific protocols that describe process details such as imaging technique, alignment method, and corrective action levels. Protocol design is challenging since its effect on treatment accuracy is currently unknown. This thesis aims to understand the interplay between lung IGRT protocol parameters by developing a framework that quantifies geometrical accuracy. Deformable image registration was used to account for changes in target shape and size throughout treatment. Sufficient accuracy was considered when at least 99% of the target surface fell within the PTV. This analysis revealed that the clinical 10 mm PTV margin can be safely reduced by at least 2 mm in each direction. Evaluation of IGRT accuracy was extended to spinal cord alignment. Simulations were carried out with various matching strategies to correct for set-up error, including rotational off-sets. Inappropriate combinations of matching strategies and safety margins resulted in sub-optimal geometrical coverage. Various lung IGRT protocol options were recommended to optimize accuracy and workflow efficiency. For example, an 8 mm PTV margin can be used with spinal cord alignment, a 4 mm cord margin, and up to 5° of rotational error. A more aggressive protocol involved a 6 mm PTV margin with direct target alignment, a 5 mm cord margin, and a 4° rotational tolerance. / Thesis / Master of Science (MSc)

Preterm infants are at risk for respiratory distress syndrome (RDS) due to immature lungs, leading to notable neonatal mortality. About 10% of US births are premature. While mechanical ventilation is a common RDS treatment, it can cause complications. If it fails, extracorporeal membrane oxygenation (ECMO) is employed, but standard ECMO devices are not suited for preterm babies. The limitations of hollow fiber membrane oxygenators used in ECMO have spurred interest in an artificial placenta that connects to the umbilical cord and supports lung growth. Microfluidic blood oxygenators, with their biomimetic designs, have being explored for this purpose. This thesis advances microfabrication techniques for Lung Assist Devices (LADs), focusing on two main objectives: I. Improving Throughput for Elevated Blood Flow Rates: This section delves into refining Microfluidic Blood Oxygenators (MBOs) to accommodate greater blood flow rates. By combining parallel units, we increased throughput and optimized LAD designs. Newly designed MBOs, with an expanded gas exchange surface area, can manage blood flow rates up to 60 mL/min. Using these enhanced MBOs, we constructed a novel LAD achieving superior oxygenation compared to predecessors. Our in vitro tests confirmed that this LAD can sustain blood flow rates of up to 150 ml/min, elevating oxygen saturation by approximately 20%—equivalent to an oxygen transfer of 7.48 mL/min, a leading figure for AP-type devices. II. Hierarchically Designed Microchannels: The second objective revolves around developing microchannels with a hierarchical layout to mitigate stagnation and high shear stress regions. Traditional photolithography poses challenges at channel intersections, inducing clotting risks. We pioneered alternative microfabrication methods, yielding diverse microchannels and intricate hierarchical designs that emulate natural vascular networks devoid of dead zones. These advancements have propelled the microfabrication domain for artificial placenta-like LADs. Utilizing our method, we produced channels varying from hundreds to a few microns in height with a single exposure and an opal diffuser. Thin membranes (~60 µm top and ~45 µm bottom) were amalgamated, culminating in a total depth of about 200 µm. Such oxygenators excel in oxygenating blood even at intense flow rates of up to 15 mL/min per unit. Leveraging these hierarchically designed MBOs, we crafted a LAD supporting a flow rate of 100 mL/min, offering an oxygen transfer of 5.21 mL/min. Both LADs developed in this research proficiently support premature neonates weighing up to 2 kg. Notably, the priming volume of the LAD using the enhanced MBOs has been substantially minimized, underscoring its advancements over earlier models. Realizing these objectives can transform neonatal care, addressing respiratory challenges in premature neonates and bolstering their chances for a healthier life. / Thesis / Master of Science (MSc)

Background and aim: Lung cancer is the leading cause of cancer incidence and mortality in Canada. Population-based screening programs using low dose computed tomography are being more widely used. Screening reduces lung cancer mortality. It also introduces potential ethical issues that need to be elucidated to inform the ethical, equitable, and effective implementation of screening programs. This aim of this research was to begin developing an understanding of what the ethical issues are and how they are being, and should be, approached in health policy. Methods: Using empirical ethics inquiry, this research produced descriptive evidence via three independent studies: a systematic literature review and mixed methods integrative synthesis of public perspectives on screening benefits and harms, and two qualitative description studies about public and key informants’ ethical and social values on ethical issues in screening. Results: The major finding of this research was the preponderance of ethical issues located within health and social systems and structures, including equity of screening access, stigma against people who currently smoke commercial tobacco, commercialization of tobacco, and the need for increased investment in primary prevention of lung cancer. These ethical issues reflect the social, economic, and political determinants of lung cancer and the means available to reduce the burden of lung cancer in Canada, including but not limited to screening. In health policy, there was a lack of ethical frameworks or principles currently being used to address these ethical issues and the sometimes-conflicting perspectives found between the public and key informants. Discussion: Future empirical and normative research is needed to understand ethical and social values related to screening by populations with high lung cancer incidence and mortality, and to integrate empirical evidence with appropriate ethical theories to make recommendations for ethical, equitable, and effective population-based LDCT lung cancer screening policy in Canada. / Thesis / Candidate in Philosophy / Lung cancer is the top cause of cancer in Canada. An estimated 30,000 people were diagnosed with lung cancer and 20,700 people died from lung cancer in 2022. Screening is being more widely used to find and treat lung cancer in earlier stages. There are some ethical questions to consider, like how to ensure that screening programs are fair and effective. This research focused on understanding what the ethical issues are and how they could be solved in health policy. Perspectives on ethical issues were collected and analyzed from the public and lung cancer screening leaders. The two major ethical issues were fair access to screening and stigma against people who currently smoke commercial tobacco. There was a lack of ethical guidance to address these issues in health policy. Ethical concepts about justice and individual choice, and ethics research with key communities, may help navigate ethical issues in health policy.

京都大学 / 0048 / 新制・課程博士 / 博士(薬科学) / 甲第22752号 / 薬科博第126号 / 新制||薬科||14(附属図書館) / 京都大学大学院薬学研究科薬科学専攻 / (主査)教授 金子 周司, 教授 土居 雅夫, 教授 竹島 浩 / 学位規則第4条第1項該当 / Doctor of Pharmaceutical Sciences / Kyoto University / DFAM