Citations

Abstract Rationale: Hematopoietic cell transplantation (HCT) risk scores have seen minimal updates over the past 20 years, despite advancements in clinical practice. Pulmonary function test (PFT) thresholds, initially based on NHANES reference equations, now have alternative reference standards from the Global Lung Function Initiative (GLI) 2012 and GLI-Global, which may reclassify patients and affect outcomes. This study investigates the impact of GLI reclassification on outcomes in HCT, comparing traditional fixed thresholds with continuous (z-score) risk assessment models. Methods: A retrospective review of 3,120 adult patients who underwent autologous HCT at MD Anderson Cancer Center from 1999 to 2015 was conducted. Primary endpoints were ICU admission, mechanical ventilation (IMV), and survival within 120 days post-transplant. PFT measures (FEV1, FVC, DLCO) were calculated using GLI-2012 and GLI-Global reference equations, analyzed both continuously (z-scores) and categorically by ATS/ERS guidelines. Cox proportional hazards and logistic regression models were employed, with AUROC comparisons to evaluate predictive performance. Results: The cohort had a mean age of 49 years (SD 14), with 41% female and 77% White. Of the 3,120 patients included in the study, the cohort consisted of 77% White, 5.4% Black, 3.3% Asian, and 14% identifying as other ethnicities. At 120 days, mortality was 1% (n=41), ICU admission 5% (n=169), and IMV 2% (n=70). Continuous DLCO was associated with a lower risk of mortality (HR: 0.75; p=0.03), ICU admission (OR: 0.83; p=0.01), and IMV (OR: 0.80; p=0.02). GLI-Global's FEV1 z-scores were also significant for mortality (HR: 0.70; p=0.01), ICU admission (OR: 0.74; p<0.0001), and IMV (OR: 0.70; p=0.0003). Categorical analyses showed significant mortality reduction with normal DLCO (HR: 0.46; p=0.01) and ICU admission reduction with normal FEV1 GLI-2012 (OR: 0.63; p=0.02). Reclassification by race, as shown in Figure 1, indicated that race-specific equations overestimated PFT values in Black patients and underestimated them in Asian patients. Conclusion: Reclassification by GLI reference equations, particularly using continuous z-scores, significantly influences post-HCT outcomes, suggesting that continuous assessment may improve risk stratification. Including race does not improve the model's performance. These findings support integrating updated PFT references and continuous risk models into HCT prognostic tools for enhanced clinical decision-making.

Abstract Rationale: Patients with fibrotic interstitial lung (f-ILD) disease often have decreased physical activity (PA) due to high symptom burden, with shortness of breath, cough, anxiety, and fatigue affecting health-related quality of life (HR-QOL). Previously undiagnosed anxiety and depression has been described in f-ILD though contributing factors remain unknown. We hypothesize that significant rates of disease-related anxiety and depression may be detected but not persist, representing situational or short-term responses to disease burden. We also hypothesize that real-world PA is an important contributor to or reflection of HR-QOL and associated with selected patient-reported outcome measures (PROMs). Methods: This was a single-center prospective observational cohort enrolling adult patients with established f-ILD. PROM questionnaires were sent electronically to patients at study enrollment and 3 months. These included the Modified Medical Research Council (mMRC), Fatigue Severity Scale (FSS), Generalized Anxiety Disorder-7 (GAD-7), Patient Health Questionnaire-9 (PHQ-9), Self-Management Ability Scale-30 (SMAS-30), and abbreviated Prolife of Mood States (POMS). PA was defined as mean number of steps per day over a 7-day period as measured by at-home Actigraphy, obtained at enrollment and 3 months (within 2 weeks of completing PROM questionnaires). Results: Forty five patients were included (mean age 69, female 49 %, non-IPF f-ILD 78%, mean forced vital capacity 77%). Baseline GAD-7 anxiety scores were ‘moderate’ in 45% and ‘severe’ in 5%. PHQ-9 depression scores were ‘moderately severe’ in 30% and ‘severe’ in 5%. Mean GAD-7 and PHQ scores were no different at baseline and three months (GAD7 10.18 vs 10, P = 0.653; PHQ-9 12.82 vs 13.32, P = 0.294). mMRC, FSS, and SMAS-30 scores were associated with daily step activity. A one-point increase in mMRC or FSS (greater dyspnea or fatigue) was associated with a decrease in daily steps of 1400 [CI: (-2000, -600), ] or 90 steps [CI: (-160, -15))], respectively. A one-point increase in SMAS-30 (greater self-management) was associated with an increase of 108 steps per day [CI: (25, 190-0.38) ]. Anxiety, depression, and mood did not appear to be associated with step activity GAD-7-4.5 (P = 0.982), PHQ-9-211.5 (P = 0.13), POMS -36.5 (P = 0.096). Conclusions: Clinical symptoms of anxiety and depression are prevalent in patients with f-ILD and do not appear diminished or improved in the short term. Dyspnea, fatigue, and self-management ability are associated with real-world measures of physical activity.

Abstract RATIONALE: The diagnosis of Pulmonary Embolism (PE) is associated with high mortality and morbidity. In patients with cancer, high-risk pulmonary emboli further escalate these risks. Ensuring access to the necessary resources for appropriate intervention is crucial for improving patient outcomes. However, the resource-intensive nature of managing multiple life-threatening conditions can create barriers for certain demographic populations, leading to disparities in outcomes. To address this issue, we explored mortality trends among diverse groups based on gender, ethnicity, and geographical background in the United States from 1999-2000. METHODS: We obtained mortality data from death certificate queries in the Centers for Disease Control and Prevention Wide-range Online Data for Epidemiologic Research database. Queries included all decedents with the underlying cause of death being PE (I26) in patients with a diagnosis of cancer (C00 – C97). Age-adjusted mortality rates (AAMR) per 100,000 people were compared across demographic populations, and 95% Confidence Intervals were standardized to the year 2000. Log-linear regression models were utilized to assess temporal mortality shifts and calculate annual percentage change (APC) from 1999 to 2020. RESULTS: A total of 179483 PE-related deaths was reported in patients with cancer. The AAMR increased from 2.14 [2.08-2.19] in 1999 to 3.05 [3.00-3.11] in 2020. The cumulative AAMR was 2.42 [2.41-2.43] with an average APC of +1.56% (p<0.001). The mortality rate accelerated following the year 2016, with the years prior having an APC of +0.69%, (p<0.001) and the years following having an APC +5.33% (p<0.001). A higher mortality was observed in males (AAMR 2.71 [2.69-2.73]) than females (2.20 [2.18-2.21]), in rural communities (AAMR 2.50 [2.47-2.53]) compared to urban communities (AAMR 2.38 [2.37-2.40]), and in non-Hispanic (AAMR 2.48 [2.47-2.49]) populations over Hispanic populations (AAMR 1.45 [1.42-1.48]). Mortality was highest in the Black population (AAMR 3.65 [3.60-3.69]), followed by White population (AAMR 2.33 [2.32-2.34]), American Natives (AAMR 1.43 [1.33-1.54]), and Asian (AAMR 1.04 [1.00-1.08]). Geographically, Midwest (AAMR 2.58 [2.56-2.61]) had the highest mortality while the South (AAMR 2.26 [2.24-2.28]) had the lowest mortality. CONCLUSIONS: We identified significant disparities in mortality related to pulmonary embolism (PE) among cancer patients across different demographic populations. Further investigation into these healthcare inequities is essential for addressing the disparities affecting various groups.

Abstract Introduction: Pulmonary sclerosing pneumocytoma, formerly known as sclerosing hemangioma, is an uncommon benign neoplasm most recently classified by the World Health Organization as an adenoma. It occurs most commonly in middle-aged women of East Asian descent, in whom it is most often discovered incidentally on imaging. It typically appears as a single, well-circumscribed lesion on CT that lacks specific defining characteristics and can appear similar to malignancies such as pulmonary adenocarcinoma. Therefore, diagnosis relies on histopathology. The tumor is derived from respiratory epithelial cells expressing TTF-1 in both round and surface cells, and immunohistochemistry (IHC) staining is positive for both TTF-1 and EMA. Description of Case: A 52-year-old female from Southeast Asia presented to primary care clinic reporting atypical chest pain. She denied shortness of breath, cough, fever, night sweats, or weight loss. She had no prior smoking history, but there was a remote history of chewing tobacco. Chest x-ray revealed a retrocardiac left lower lobe pulmonary nodule. CT chest was obtained and revealed a solid left lower lobe pulmonary nodule measuring 2.2 cm in diameter. The nodule was mildly FDG avid on subsequent PET-CT with SUVmax 2.8, noted to be suspicious for a lesion on the pulmonary adenocarcinoma spectrum. She opted for surgical removal and underwent thoracoscopic left lower lobe wedge resection. Pathology demonstrated sclerosing pneumocytoma with IHC stains positive for TTF1, EMA, and keratin AE1/AE3. The follow-up CT chest showed no evidence of local recurrence or residual tumor. Discussion: Pulmonary sclerosing pneumocytoma is an uncommon benign neoplasm of the lung that can be easily mistaken for malignancy such as pulmonary adenocarcinoma given its imaging characteristics and FDG avidity on PET-CT. It must be considered in the differential for lung nodules, particularly in middle-aged women of East Asian descent. Diagnosis is made with biopsy showing both cuboidal surface cells and stromal round cells, with IHC staining positively for TTF-1 and EMA. However, these tumors remain difficult to diagnose in frozen section, small biopsies, and cytology, because they are easily mistaken for adenocarcinoma or carcinoid tumors. The clinical course is generally benign, but very rarely there is metastasis or recurrence.

Abstract RATIONALE: As technology for biopsy of peripheral pulmonary nodules advances, the size of suspicious nodules referred for biopsy has decreased. This can be partly attributed to tools such as shape-sensing robotic-assisted bronchoscopy (ssRAB), which can increase the likelihood of a diagnostic result. Literature describing the biopsy of sub-centimeter nodules is primarily single center with a reported diagnostic yield for robotic bronchoscopy of 67%1, and 71%2 for CT-guided percutaneous biopsy; robust prospective multi-center data is needed to further understand the feasibility and clinical value of <1cm nodule biopsies. Herein, we report data from the prospective Ion Registry describing outcomes for patients with sub-centimeter nodules biopsied using ssRAB. METHODS: Patients with at least one (1) nodule <1cm that underwent ssRAB biopsy were identified from those enrolled in the Ion Registry. Subjects with multiple lesions were included if all nodules were <1cm in largest diameter. Nodule and procedure characteristics are reported with descriptive statistics; diagnostic yield was assessed using the ATS/ACCP recommended guidelines of index biopsy results only. Safety was assessed as the rate of pneumothorax requiring intervention and Nashville Grade ≥3 bleeding. RESULTS: Fifty-four (54) subjects and 57 sub-centimeter nodules were identified across 9 centers and 15 investigators; procedures were completed October 2023 through September 2024. The majority of nodules (47.4%) were incidental findings. Median nodule diameter was 8 mm (IQR: 7,9; range: 4.0-9.7 mm) with 66.7% of nodules located in the outer-third of the lung, and predominantly (57.9%) in the upper lobes. CT bronchus sign was present in 24.6% of nodules, and most (89.5%) nodule were solid. Median procedure time was 34.5 mins (IQR: 26,47; range: 9-89 mins); fixed or mobile CBCT was utilized for 80.7% (46/57) of nodules. The flexision biopsy needle and cryoprobe were used in 91% and 49% of biopsies, respectively. Diagnostic yield was 83% (45/54) using index biopsy results, 59% of which were malignant. No (0%) pneumothorax requiring intervention, Nashville Grade ≥3 bleeding events. CONCLUSION: Preliminary results from this prospective, multi-center registry cohort demonstrate peripheral nodules <1cm can be safely and effectively diagnosed through ssRAB biopsy and highlight the impact of ssRAB in enhancing lung nodule diagnosis, particularly when combined with CBCT. These findings suggest ssRAB may be considered a viable option for the biopsy of suspicious sub-centimeter nodules, further optimizing the management of patients with suspected lung cancer. REFERENCES:1. 10.1016/j.chest.2021.07.2169 2. https://doi.org/10.1016/j.clinimag.2020.04.040

Abstract Rationale Pulmonary function tests (PFT) are interpreted in the context of reference values that were based on sex, age, height and previously race/ethnicity. The Global Lung Function Initiative (GLI) published spirometry references equations in 2012 and static lung volume reference equations in 2021. In 2023, the American Thoracic Society recommended removal of race from predictive equations for spirometry using the new race-neutral GLI-Global reference equations. Since the change of spirometry reference equations, we have noticed an increase in number of patients with normal spirometry but a low total lung capacity (TLC), where historically the incidence was less than 5 percent and normal spirometry was used to exclude restriction. The goal of this study was to further investigate this observation and characterize the population of patients with normal spirometry and reduced TLC, which we termed occult restriction. Methods We analyzed our existing PFT database which included 28,415 spirometry tests performed at Mayo Clinic Rochester and Mayo Clinic Florida between 2013 to 2016. 26,856 tests included lung volume measurements. The spirometry was interpreted using both GLI-2012 and GLI-Global reference equations and TLC was interpreted using GLI lung volume reference equations. Patients’ demographics including self-identified race were obtained. Patients with occult restriction were further characterized using descriptive statistics. All data analysis was done using BlueSky Statistics Version 10.3.1. Results Our study showed that 920 (3.4%) patients with normal spirometry using GLI-2012 reference equations had low TLC, while 1526 (5.7%) patients with normal spirometry using GLI-Global reference equations had low TLC. Among these patients, 697 patients had a change from abnormal to normal spirometry interpretation and 91 patients had a change from normal to abnormal spirometry interpretation when using GLI-Global reference equations. Comparing patients of different races and ethnicities, there is increased incidence of occult restriction in Caucasian patients with transition to GLI-Global, while the incidence of occult restriction decreased in African American patients. Patients who identify as African American or Southeast Asian are more likely to have occult restriction than others (Table 1). Conclusions With the change from GLI-2012 to GLI-Global spirometry reference equations, the frequency of occult restriction has increased from 3.4% to 5.7% with predominant effect on Caucasian patients. The clinical implication of this finding requires further study but clinicians need to be vigilant that a normal spirometry may not exclude restrictive lung disease using our current reference equations.

Abstract RATIONALE: Mitochondria show cell and context-specific heterogeneity in their morphometry, determined by regulators of mitochondrial dynamics. Previously, we reported that TNFα increased maximum O2 consumption rate (OCR) and mitochondrial volume density (MVD) in human airway smooth muscle (hASM) cells. However, when normalized to mitochondrial volume, maximum OCR per mitochondrion was reduced following TNFα exposure. TNFα exposure also altered mitochondrial distribution and motility within hASM cells relative to the nuclear membrane. Although high-resolution respirometry is a valuable tool for assessing mitochondrial function, it does not account for the presence of mitochondrial structural and functional heterogeneity within cells. Therefore, a direct measurement of cellular mitochondrial function provides valuable novel information and physiological insight. Previously, we developed a confocal-based quantitative histochemical technique to determine the maximum velocity of the succinate dehydrogenase (SDH) reaction (SDHmax) in single cells and observed that cellular SDHmax corresponds with MVD. Therefore, we hypothesize that SDH activity varies relative to the intracellular mitochondrial distribution within hASM cells. METHODS: Cells were dissociated from bronchiolar tissue samples collected from female and male patients with no history of smoking or respiratory disease. Isolated hASM cells were serum-deprived for 48 h and split into two treatment groups: 1) TNFα-treated (20 ng/mL, 6 h and 24 h) and 2) time-matched untreated control. Following treatments, CellLight GFP-labeled mitochondria were imaged in 3D (Z optical slice of 0.5 μm) on a Nikon Eclipse A1 laser scanning confocal system (oil-immersion ×60/1.4 NA objective). Using a concentric shell method for analysis, MVD, mitochondrial complexity index (MCI) and SDHmax were quantified relative to the nuclear membrane. SDHmax was measured using a solution containing 80 mM succinate (maximum substrate concentration) and 1.5 mM nitroblue tetrazolium (reaction indicator). As the reaction proceeded, the change in optical density (OD), was measured every 15 s over a 10-min period. Using the Beer-Lambert equation, the change in OD was used to determine SDHmax expressed as mmol fumarate/L cell/min. RESULTS: Within each shell, SDHmax and MVD peaked in the perinuclear region and decreased toward the distal compartments of the cell in all treatment groups. When normalized to mitochondrial volume, SDHmax decreased in the perinuclear region compared to the distal compartments of the cell. Compared to control, TNFα exposure caused a significant shift in mitochondrial morphometry and function relative to the nuclear membrane. CONCLUSIONS: In summary, our data indicate that mitochondria within individual cells are morphologically heterogeneous with distinct functional properties, which is disrupted in disease.

Abstract Rationale: With an increasing elderly population, understanding mechanisms that contribute to structural and functional changes in aging lung is important in the context of healthy aging and diseases such as asthma and pulmonary fibrosis that disproportionately affect the elderly. Asthma in the elderly (AIE) is a particular challenge, with thickened fibrotic bronchial airways (remodeling) and inflammation compared to non-asthmatic elderly: issues not addressed by current therapies. Factors such as iron regulation that are critical for normal physiology can become dysregulated in disease. Iron overload can catalyze a Fenton reaction that increases ROS which oxidizes lipids and proteins, i.e. iron-mediated lipid peroxidation cell death (ferroptosis).The goal of this study was to determine iron regulation in aging- and AIE-associated in human ASM (hASM), a cell type important in airway contractility and remodeling. Methods: hASM cells and lung tissues from young (<45y), and aged (>65y) male/female patients with/without asthma were used (approved by Mayo IRB #16-009655). Cells were treated with ferroptosis inhibitor deferoxamine (DFO) [100µM], inducer RSL3 [125 nM] or vehicle (DMSO) for 24 hrs. Levels of intracellular iron (Fe2+) were determined using FerroOrange. Cell lysates were examined for iron accumulation and ferroptosis markers (4-HNE, FTH1, TfR1, SLC7A11, and KEAP1), cell proliferation, and ECM production (COL1A1 and FN1), and supernatants analyzed for proinflammatory mediators IL-6 and IL-8. Results: Non-asthmatic and asthmatic elderly hASM cells showed a higher cytosolic Fe2+ and lower end-product of lipid peroxidation (4-HNE), higher level of SLC7A11 and KEAP1 (regulators of redox systems) compared to cells from young individuals. High level of iron storage (FTH1) was observed in asthmatics compared to non-asthmatic elderly, but no difference was observed for iron transporters (TfR1). Furthermore, COL1A1 and FN1 were higher in AIE hASM, compared to young hASM. COL1A1 was higher in aging hASM compared to young. DFO reduced COL1A1 in elderly, but upregulated in AIE. Cell proliferation was inhibited by DFO in aging hASM but not in young and AIE. The ferroptosis inducer RLS3 impaired antioxidant system and increased lipid peroxidation and IL-8 levels. Conclusions: Our findings suggest that iron regulation is impaired in aging and AIE hASM, resulting in iron accumulation which modulates airway remodeling via cell proliferation and ECM production. While ferroptosis per se can be targeted, it will be important to explore modulation of specific iron regulatory pathways in alleviating the impact of aging and asthma.

Abstract Rationale : Airway remodeling in asthma involves increased airway smooth muscle (ASM) mass, changes to bronchial epithelial cell (BEC) layer, and increased fibrosis. ASM and BECs actively contribute by secreting growth factors and cytokines, regulating extracellular matrix (ECM) composition and enhancing cell proliferation/migration. Altering mechanisms which modulate remodeling presents a key to novel therapeutic strategies. BDNF increases ASM [Ca2+]i and contractility, and potentiates the effects of inflammation. Importantly, studies show that ASM is not only a target, but also a source of BDNF, raising the possibility of local autocrine/paracrine effects. Arginase 1 and 2 are expressed by BECs, but their roles in asthma are still under investigation with studies showing arginase 1 inhibition blunting epithelial remodeling and ASM hyperplasia. Knockdown of appealing targets such as ASM BDNF and epithelial arginases using small interfering RNA (siRNA) is a promising approach to combating inflammatory lung remodeling. Polymer based nanoparticles have been constructed which demonstrate cell-type specificity and high efficiency in delivering siRNA. Thus, we hypothesize that BDNF and arginases are central to airway remodeling and can be targeted via nanopartiacles.Methods: Primary human ASM and BEC cells from non-asthmatic vs. asthmatic individuals were obtained post-surgery from lung tissues after approval Mayo Clinic IRB. PONI-Guan NP were generated using block copolymer engineering. PCR, immunoblotting and ELISA were performed using standard techniques. Contractility studies were conducted in adult mouse precision cut lung slices. In vivo lung function studies were conducted in 6-8 week old mice, with or without mixed allergen (MA) treatment and Scireq Flexivent system. Results: PONI-Guan NP uptake demonstrates cell-type specificity in BEC/ASM co-culture and mouse lung. Arginase I/II and ECM expression is upregulated in BECs when exposed to BDNF and cytokines. In ASM, BDNF is increased in asthmatics compared to non-asthmatic controls; ECM expression is increased in response to BDNF and TNF-α. In BEC, PONI-Guan NP/siRNA inhibits Arg I/II expression, even in the presence of TNF-α. In ASM, TNF-α increases in BDNF secretion and ECM deposition are blunted by NP-delivered siRNA. PCLS and mouse lung function studies show contractility to MCh: effects suppressed by NP-delivered BDNF and Arg I siRNA. Conclusions: Our studies show the importance of BDNF/Arginase pathways in airway remodeling and efficacy of PONI-based siRNA delivery vectors in blunting remodeling processes.

Abstract Rationale: Within the asthmatic lung, inflammatory signaling alters the contractile capacity of airway smooth muscle (ASM). In chronic inflammation, ASM become hypercontractile and are a key contributor toward airway hyperresponsiveness (AHR). As a heterogenous disorder, several asthmatic endotypes have been defined. A severe ASM endotype is partly defined as being glucocorticoid insensitive. We have reported the role of Kisspeptin (Kp)/KISS1R signaling in the lung in the context of airway fibrosis. In this study, KISS1R and Kp-10 were investigated for a potential interactions with intracellular calcium [Ca2+]i signaling and ASM contractility in the in vitro setting of severe asthmatic endotypes. Methods: Primary ASM were obtained from non-pathological samples from the Mayo Clinic. ASM cells were treated with inflammatory cytokines (TNFα 20 ng/ml, or IL-13 50 ng/mL)± Kp-10 (1 μM). The steroid-insensitive asthma endotype was investigated using pro-inflammatory cytokines (TNFα 20 ng/ml and IFN-γ 25 ng/mL) ± a corticosteroid (Fluticasone Propionate 100 nM). Β2-Adrenergic Receptor (β2-AR) desensitized endotypes were developed by treating cells with a β2-AR agonist (Salbutamol 1 μM) for 24 hours prior to and along with cytokine treatments (TNFα 20 ng/ml and IFN-γ 25 ng/mL or IL-13 50 ng/mL) ± Kp-10. [Ca2+]i was measured via Fura-2AM (4 μM) labeling on an Olympus Fluoview 300 microscope. Myosin light chain (MLC) phosphorylation studies were used to quantify downstream mechanics of ASM contractility. Results: KISS1R activation in IL-13 treated cells reduced [Ca2+]i in response to histamine. In contrast, TNFα treated cells were responsive to Kp-10 for acute treatments, however this effect was lost after 24 hours of Kp-10 treatment. TNFα and IFN-γ treated cells showed a robust [Ca2+]i response to histamine, and both fluticasone (∼20% reduction) and Kp-10 (∼10% reduction) alone had a minimal effect in reducing [Ca2+]i. Fluticasone and Kp-10 co-exposure significantly reduced [Ca2+]i and significantly reduced the effect of TNFα/IFN-γ (∼45% reduction). In B2-AR desensitized cells, Kp-10 exposure maintained the effect of reducing [Ca2+]i, suggesting Kp-10/KISS1R signaling works through an alternate or independent pathway. Kp-10 treatments on cytokine exposed cells reduced p-MLC in response to histamine, suggesting a role in ASM contractility. Conclusion: The increase of [Ca2+]i in inflamed cells is associated with AHR; Kp-10/KISS1R signaling showed varying efficacy in reducing [Ca2+]i within inflammatory endotypes. These results also highlight that Kp-10 acts synergistically with the current therapeutics available for asthma.