Idiopathic Pulmonary Fibrosis
Lipocalin-2 as a prognostic marker in patients with acute exacerbation of idiopathic pulmonary fibrosis
Respir Res. 2024 May 4;25(1):195. doi: 10.1186/s12931-024-02825-y.
ABSTRACT
BACKGROUND: Lipocalin-2 (LCN2) is a secretory glycoprotein upregulated by oxidative stress; moreover, patients with idiopathic pulmonary fibrosis (IPF) have shown increased LCN2 levels in bronchoalveolar lavage fluid (BALF). This study aimed to determine whether circulatory LCN2 could be a systemic biomarker in patients with IPF and to investigate the role of LCN2 in a bleomycin-induced lung injury mouse model.
METHODS: We measured serum LCN2 levels in 99 patients with stable IPF, 27 patients with acute exacerbation (AE) of IPF, 51 patients with chronic hypersensitivity pneumonitis, and 67 healthy controls. Further, LCN2 expression in lung tissue was evaluated in a bleomycin-induced lung injury mouse model, and the role of LCN2 was investigated using LCN2-knockout (LCN2 -/-) mice.
RESULTS: Serum levels of LCN2 were significantly higher in patients with AE-IPF than in the other groups. The multivariate Cox proportional hazards model showed that elevated serum LCN2 level was an independent predictor of poor survival in patients with AE-IPF. In the bleomycin-induced lung injury mouse model, a higher dose of bleomycin resulted in higher LCN2 levels and shorter survival. Bleomycin-treated LCN2 -/- mice exhibited increased BALF cell and protein levels as well as hydroxyproline content. Moreover, compared with wild-type mice, LCN2-/- mice showed higher levels of circulatory 8-isoprostane as well as lower Nrf-2, GCLC, and NQO1 expression levels in lung tissue following bleomycin administration.
CONCLUSIONS: Our findings demonstrate that serum LCN2 might be a potential prognostic marker of AE-IPF. Moreover, LCN2 expression levels may reflect the severity of lung injury, and LCN2 may be a protective factor against bleomycin-induced acute lung injury and oxidative stress.
PMID:38704585 | DOI:10.1186/s12931-024-02825-y
Issue 3-The occupational burden of respiratory diseases, an update
Pulmonology. 2024 May 3:S2531-0437(24)00045-X. doi: 10.1016/j.pulmoe.2024.03.004. Online ahead of print.
ABSTRACT
INTRODUCTION AND AIMS: Workplace exposures are widely known to cause specific occupational diseases such as silicosis and asbestosis, but they also can contribute substantially to causation of common respiratory diseases. In 2019, the American Thoracic Society (ATS) and the European Respiratory Society (ERS) published a joint statement on the occupational burden of respiratory diseases. Our aim on this narrative review is to summarise the most recent evidence published after the ATS/ERS statement as well as to provide information on traditional occupational lung diseases that can be useful for clinicians and researchers.
RESULTS: Newer publications confirm the findings of the ATS/ERS statement on the role of workplace exposure in contributing to the aetiology of the respiratory diseases considered in this review (asthma, COPD, chronic bronchitis, idiopathic pulmonary fibrosis, hypersensitivity pneumonitis, infectious pneumonia). Except for COPD, chronic bronchitis and infectious pneumonia, the number of publications in the last 5 years for the other diseases is limited. For traditional occupational lung diseases such as silicosis and asbestosis, there are old as well as novel sources of exposure and their burden continues to be relevant, especially in developing countries.
CONCLUSIONS: Occupational exposure remains an important risk factor for airways and interstitial lung diseases, causing occupational lung diseases and contributing substantially in the aetiology of common respiratory diseases. This information is critical for public health professionals formulating effective preventive strategies but also for clinicians in patient care. Effective action requires shared knowledge among clinicians, researchers, public health professionals, and policy makers.
PMID:38704309 | DOI:10.1016/j.pulmoe.2024.03.004
Combination of co-amorphization with SNEDDS outperforms Ofev® in the oral absorption of nintedanib
Int J Pharm. 2024 May 2:124197. doi: 10.1016/j.ijpharm.2024.124197. Online ahead of print.
ABSTRACT
Nintedanib (NTD), approved for the treatment of idiopathic pulmonary fibrosis and advanced non-small cell lung cancer, is one of brick dusts with high melting point. Although NTD has been marketed as Ofev®, a soft capsule of NTD ethanesulfonate (NTD-ESA) suspended in oil components, the oral bioavailability is quite low and highly variable. To improve the oral absorption behavior of NTD, we prepared SNEDDS formulation containing NTD-(+)-10-camphorsulfonic acid (CSA) complex with 2 % HPMCP-50. CSA disrupted the high crystallinity of NTD-ESA and the formed complex, NTD-CSA, was found to be amorphous by DSC and XRPD. NTD-CSA provided solubilities in various vehicles much higher than NTD-ESA. Under the gastric luminal condition, NTD-CSA SNEDDS with or without 2 % HPMCP-50 and NTD-CSA powder indicated very good dissolution of NTD from early time periods, while NTD was gradually dissolved until around 60 min from NTD-ESA and Ofev®. Under the small intestinal luminal condition, in contrast, both NTD-CSA SNEDDS formulations almost completely dissolved NTD throughout the experiments, while Ofev®, NTD-CSA, and NTD-ESA exhibited a very poor dissolution of NTD. In the in vivo absorption study, NTD-CSA SNEDDS with 2 % HPMCP-50 significantly improved NTD absorption and reduced the inter-individual variation in oral absorption behavior compared with Ofev®.
PMID:38703930 | DOI:10.1016/j.ijpharm.2024.124197
Urea cycle promotion via ammonia-upregulated CPS1 is involved in arsenite-induced pulmonary fibrosis through enhancing collagen synthesis
Chem Biol Interact. 2024 May 2:111029. doi: 10.1016/j.cbi.2024.111029. Online ahead of print.
ABSTRACT
Arsenic exposure is connected with lung toxicity and is related to lung fibrotic changes. Idiopathic pulmonary fibrosis (IPF) is characterized by extracellular matrix (ECM) deposition. Various genetic mechanisms and environmental factors induce or exacerbate pulmonary fibrosis. Collagen synthesis induced by arsenite (NaAsO2) is closely associated with IPF. Fibroblasts tend to fine-tune their metabolic networks to support their synthetic requirements in response to environmental stimuli. Alterations in metabolism have an influential role in the pathogenesis of IPF. However, it is unclear how arsenic affects the metabolism in IPF. The urea cycle (UC) is needed for collagen formation, which provides adequate levels of proline (Pro) for biosynthesis of collagen. Carbamoyl phosphate synthetase 1 (CPS1) converts the ammonia to carbamoyl phosphate, which controls the first reaction of the UC. We show that, in arsenite-exposed mice, high amounts of ammonia in the lung microenvironment promotes the expression levels of CPS1 and the Pro metabolism. Reduction of ammonia and CPS1 ablation inhibit collagen synthesis and ameliorate IPF phenotypes induced by arsenite. This work takes advantage of multi-omics data to enhance understanding of the underlying pathogenic mechanisms, the key molecules and the complicated cellular responses to this pollutant, which provide a target for the prevention of pulmonary fibrosis caused by arsenic.
PMID:38703806 | DOI:10.1016/j.cbi.2024.111029
Shared biomarkers and mechanisms in idiopathic pulmonary fibrosis and non-small cell lung cancer
Int Immunopharmacol. 2024 May 3;134:112162. doi: 10.1016/j.intimp.2024.112162. Online ahead of print.
ABSTRACT
BACKGROUND: Epidemiological evidence has indicated the occurrence of idiopathic pulmonary fibrosis (IPF) with coexisting lung cancer is not a coincidence. The pathogenic mechanisms shared between IPF and non-small cell lung cancer (NSCLC) at the transcriptional level remain elusive and need to be further elucidated.
METHODS: IPF and NSCLC datasets of expression profiles were obtained from the GEO database. Firstly, to detect the shared dysregulated genes positively correlated with both IPF and NSCLC, differentially expressed analysis and WGCNA analysis were carried out. Functional enrichment and the construction of protein-protein network were employed to reveal pathogenic mechanisms related to two diseases mediated by the shared dysregulated genes. Then, the LASSO regression was adopted for screening critical candidate biomarkers for two disorders. Moreover, ROC curves were applied to evaluate the diagnostic value of the candidate biomarkers in both IPF and NSCLC.
RESULTS: The 20 shared dysregulated genes positively correlated with both IPF and NSCLC were identified after intersecting differentially expressed analysis and WGCNA analysis. Functional enrichment revealed the 20 shared genes mostly enriched in extracellular region, which is critical in the organization of extracellular matrix. The protein-protein networks unrevealed the interaction of the 11 shared genes involving in collagen deposition and the connection between PYCR1 with PSAT1. PSAT1, PYCR1, COL10A1 and KIAA1683 were screened by the LASSO regression. ROC curves comprising area under the curve (AUC) verified the potential diagnostic value of PSAT1 and COL10A1 in both IPF and NSCLC.
CONCLUSIONS: We revealed dysregulated extracellular matrix through aberrant expression of the relevant genes, which provided further understanding for the common molecular mechanisms predisposing the occurrence of both IPF and NSCLC.
PMID:38703565 | DOI:10.1016/j.intimp.2024.112162
Acute exacerbation predicting poor outcomes in idiopathic interstitial pneumonia and advanced lung cancer patients undergoing cytotoxic chemotherapy
Sci Rep. 2024 May 3;14(1):10162. doi: 10.1038/s41598-024-60833-w.
ABSTRACT
Effective treatment for advanced lung cancer and idiopathic interstitial pneumonia (IIP) remains an unmet medical need. The relationship between chemotherapy's effectiveness in advanced lung cancer and the risk of acute exacerbation of IIP is poorly investigated. There is limited evidence that patients who experience an acute exacerbation of IIPs during cytotoxic chemotherapy have poorer outcomes than those who do not. Among 1004 patients with advanced lung cancer and IIPs enrolled in our published multi-centre retrospective study from 110 Japanese institutions, 708 patients (male: female, 645:63; mean age, 70.4) received first-line chemotherapy. The occurrence of chemotherapy-triggered acute exacerbations of IIPs and overall survival (OS) were analysed. The OS between groups of patients with and without the occurrence of acute exacerbation was compared at four landmark time points (30, 60, 90, and 120 days), starting from the first-line chemotherapy, using the landmark method. The incidence of acute exacerbation in patients who received first-line chemotherapy with small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC) was more frequent in NSCLC patients than in SCLC (4.2% vs 12.6%; odds ratio [OR]: 3.316; 95% confidence interval [CI] 1.25-8.8). Median survival time was 9.9 months (95% CI 9.2-10.7). Patients who experienced acute exacerbation had significant worse survival outcomes than those who did not at various time points (30 days, hazard ratio [HR]: 5.191, 95% CI 2.889-9.328; 60 days, HR: 2.351, 95% CI 1.104-5.009; 90 days, HR: 2.416, 95% CI 1.232-4.739; and 120 days, HR: 2.521, 95% CI 1.357-4.681). Acute exacerbation during first-line chemotherapy can predict poor survival.Trial Registration number: UMIN000018227.
PMID:38702426 | DOI:10.1038/s41598-024-60833-w
Lung Transplantation in Patients With Systemic Scleroderma-Description of the First Consecutive Cases in Poland: Case Series Report and a Short Literature Review
Transplant Proc. 2024 May 2:S0041-1345(24)00243-4. doi: 10.1016/j.transproceed.2024.04.007. Online ahead of print.
ABSTRACT
Pulmonary complications of systemic scleroderma (SSc), such as interstitial lung disease and pulmonary hypertension (PH), are responsible for up to 60% of deaths among patients. For many years, most centers considered SSc a contraindication to lung transplantation (LTx); however, recent publications show that appropriately selected SSc candidates for LTx give results comparable to patients with idiopathic PH or idiopathic pulmonary fibrosis. This paper presents the cases of a 60-year-old male patient (patient 1) and a 42-year-old female patient (patient 2) diagnosed with SSc in 2019 and 2013, respectively. In both patients, interstitial-fibrotic changes in the lungs leading to respiratory failure were confirmed by high-resolution computed tomography as well as pulmonary hypertension (WHO group 3), which was also diagnosed during right heart catheterization. In both cases, despite pharmacotherapy, pulmonary fibrosis progressed, leading to severe respiratory failure. The patients were referred for LTx qualification. LTx was possible to consider in patients due to the lack of significant changes in other internal organs. Double LTx was successfully performed in both patients (patient 1-July 19, 2022; patient 2-September 14, 2022). They were discharged from the hospital in good condition on the 22nd and 20th postoperative day, respectively. LTx is a last-chance therapy that saves lives among patients with extreme respiratory failure in the course of SSc. It prolongs and improves the quality of life. The selection of appropriate patients is key to the success of the procedure.
PMID:38702265 | DOI:10.1016/j.transproceed.2024.04.007
Cell selective BCL-2 inhibition enabled by lipid nanoparticles alleviates lung fibrosis
J Control Release. 2024 May 1:S0168-3659(24)00284-0. doi: 10.1016/j.jconrel.2024.04.055. Online ahead of print.
ABSTRACT
Idiopathic pulmonary fibrosis (IPF) is a devastating lung disease with a high mortality rate due to limited treatment options. Current therapies cannot effectively reverse the damage caused by IPF. Research suggests that promoting programmed cell death (apoptosis) in myofibroblasts, the key cells driving fibrosis, could be a promising strategy. However, inducing apoptosis in healthy cells like epithelial and endothelial cells can cause unwanted side effects. This project addresses this challenge by developing a targeted approach to induce apoptosis specifically in myofibroblasts. We designed liposomes (LPS) decorated with peptides that recognize VCAM-1, a protein highly expressed on myofibroblasts in fibrotic lungs. These VCAM1-targeted LPS encapsulate Venetoclax (VNT), a small molecule drug that inhibits BCL-2, an anti-apoptotic protein. By delivering VNT directly to myofibroblasts, we hypothesize that VCAM1-VNT-LPS can selectively induce apoptosis in these cells, leading to reduced fibrosis and improved lung function. We successfully characterized VCAM1-VNT-LPS for size, surface charge, and drug loading efficiency. Additionally, we evaluated their stability over three months at different temperatures. In vitro and in vivo studies using a bleomycin-induced mouse model of lung fibrosis demonstrated the therapeutic potential of VCAM1-VNT-LPS. These studies showed a reduction in fibrosis-associated proteins (collagen, α-SMA, VCAM1) and BCL-2, while simultaneously increasing apoptosis in myofibroblasts. These findings suggest that VCAM1-targeted delivery of BCL-2 inhibitors using liposomes presents a promising and potentially selective therapeutic approach for IPF.
PMID:38701884 | DOI:10.1016/j.jconrel.2024.04.055
Identification of shared molecular mechanisms and diagnostic biomarkers between heart failure and idiopathic pulmonary fibrosis
Heliyon. 2024 Apr 20;10(8):e30086. doi: 10.1016/j.heliyon.2024.e30086. eCollection 2024 Apr 30.
ABSTRACT
BACKGROUND: Heart failure (HF) and idiopathic pulmonary fibrosis (IPF) are global public health concerns. The relationship between HF and IPF is widely acknowledged. However, the interaction mechanisms between these two diseases remain unclear, and early diagnosis is particularly difficult. Through the integration of bioinformatics and machine learning, our work aims to investigate common gene features, putative molecular causes, and prospective diagnostic indicators of IPF and HF.
METHODS: The Gene Expression Omnibus (GEO) database provided the RNA-seq datasets for HF and IPF. Utilizing a weighted gene co-expression network analysis (WGCNA), possible genes linked to HF and IPF were found. The Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) were then employed to analyze the genes that were shared by HF and IPF. Using the cytoHubba and iRegulon algorithms, a competitive endogenous RNA (ceRNA) network was built based on seven basic diagnostic indicators. Additionally, hub genes were identified using machine learning approaches. External datasets were used to validate the findings. Lastly, the association between the number of immune cells in tissues and the discovered genes was estimated using the CIBERSORT method.
RESULTS: In total, 63 shared genes were identified between HF- and IPF-related modules using WGCNA. Extracellular matrix (ECM)/structure organization, ECM-receptor interactions, focal, and protein digestion and absorption, were shown to be the most enrichment categories in GO and KEGG enrichment analysis of common genes. Furthermore, a total of seven fundamental genes, including COL1A1, COL3A1, THBS2, CCND1, ASPN, FAP, and S100A12, were recognized as pivotal genes implicated in the shared pathophysiological pathways of HF and IPF, and TCF12 may be the most important regulatory transcription factor. Two characteristic molecules, CCND1 and NAP1L3, were selected as potential diagnostic markers for HF and IPF, respectively, using a support vector machine-recursive feature elimination (SVM-RFE) model. Furthermore, the development of diseases and diagnostic markers may be associated with immune cells at varying degrees.
CONCLUSIONS: This study demonstrated that ECM/structure organisation, ECM-receptor interaction, focal adhesion, and protein digestion and absorption, are common pathogeneses of IPF and HF. Additionally, CCND1 and NAP1L3 were identified as potential diagnostic biomarkers for both HF and IPF. The results of our study contribute to the comprehension of the co-pathogenesis of HF and IPF at the genetic level and offer potential biological indicators for the early detection of both conditions.
PMID:38699746 | PMC:PMC11063427 | DOI:10.1016/j.heliyon.2024.e30086
Interstitial lung disease: a review of classification, etiology, epidemiology, clinical diagnosis, pharmacological and non-pharmacological treatment
Front Med (Lausanne). 2024 Apr 18;11:1296890. doi: 10.3389/fmed.2024.1296890. eCollection 2024.
ABSTRACT
Interstitial lung diseases (ILDs) refer to a heterogeneous and complex group of conditions characterized by inflammation, fibrosis, or both, in the interstitium of the lungs. This results in impaired gas exchange, leading to a worsening of respiratory symptoms and a decline in lung function. While the etiology of some ILDs is unclear, most cases can be traced back to factors such as genetic predispositions, environmental exposures (including allergens, toxins, and air pollution), underlying autoimmune diseases, or the use of certain medications. There has been an increase in research and evidence aimed at identifying etiology, understanding epidemiology, improving clinical diagnosis, and developing both pharmacological and non-pharmacological treatments. This review provides a comprehensive overview of the current state of knowledge in the field of interstitial lung diseases.
PMID:38698783 | PMC:PMC11063378 | DOI:10.3389/fmed.2024.1296890
Involvement of E3 ubiquitin ligase NEDD4-mediated YY1 ubiquitination in alleviating idiopathic pulmonary fibrosis
Int J Biol Macromol. 2024 Apr 30:131976. doi: 10.1016/j.ijbiomac.2024.131976. Online ahead of print.
ABSTRACT
Idiopathic pulmonary fibrosis (IPF) is a chronic and lethal lung disease characterized by progressive lung scarring. This study aims to elucidate the role of the E3 ubiquitin ligase NEDD4 in the ubiquitination of YY1 and its subsequent impact on TAB1 transcription, revealing a possible molecular mechanism in the development of IPF. Through bioinformatics analysis and both in vitro and in vivo experiments, we observed differential expression levels of NEDD4 and YY1 between normal and IPF samples, identifying NEDD4 as an upstream E3 ubiquitin ligase of YY1. Furthermore, binding sites for the transcription factor YY1 on the promoter region of TAB1 were discovered, indicating a direct interaction. In vitro experiments using HEPF cells showed that NEDD4 mediates the ubiquitination and degradation of YY1, leading to suppressed TAB1 transcription, thereby inhibiting cell proliferation and fibrogenesis. These findings were corroborated by in vivo experiments in an IPF mouse model, where the ubiquitination pathway facilitated by NEDD4 attenuated IPF progression through the downregulation of YY1 and TAB1 transcription. These results suggest that NEDD4 plays a crucial role in the development of IPF by modulating YY1 ubiquitination and TAB1 transcription, providing new insights into potential therapeutic targets for treating IPF.
PMID:38697427 | DOI:10.1016/j.ijbiomac.2024.131976
Unravelling the health and economic burden of interstitial lung diseases in adults in Australia
Aust J Gen Pract. 2024 May;53(5):333-336. doi: 10.31128/AJGP-02-23-6713.
ABSTRACT
BACKGROUND: Interstitial lung diseases (ILD) are a heterogenous group of over 200 disorders affecting the pulmonary interstitium. Although there have been advances in knowledge on ILDs in Australia, the characterisation of the health and economic burden of disease remained largely undetermined until recently.
OBJECTIVE: The main objective of this review is to provide a synopsis of health and economic burden of ILDs in Australia, based on recently completed research.
DISCUSSION: Recent research has demonstrated that idiopathic pulmonary fibrosis (IPF) is the most frequent ILD in Australia. Incidence and prevalence of IPF have demonstrated an increasing trend over the past decades. Mortality has also increased over the past decades, but has shown a slight decreasing trend recently, since the introduction of antifibrotic medication. Health-related quality of life is poor in patients with IPF, and care is estimated to cost approximately AU$299 million per year in Australia. Early diagnosis and referral to tertiary care is crucial for favourable outcomes, and general practitioners are considerably important to this as the first interface to identify patients at risk and detect early symptoms of ILDs.
PMID:38697068 | DOI:10.31128/AJGP-02-23-6713
Changes in physical activity in people with idiopathic pulmonary fibrosis before and after virtual pulmonary rehabilitation: a feasibility study
BMC Pulm Med. 2024 May 2;24(1):215. doi: 10.1186/s12890-024-03030-9.
ABSTRACT
BACKGROUND: Pulmonary rehabilitation (PR) is recommended for the treatment of people with idiopathic pulmonary fibrosis (IPF). Physical activity is an important health behaviour, closely linked to survival in people with IPF. Little is known about the impact of virtual (V) PR on physical activity in people with IPF.
OBJECTIVE: To explore the feasibility of conducting a trial to explore effect of virtual PR on objectively measured physical activity in people with IPF.
METHODS: All patients with a diagnosis of IPF in a stable phase of the disease were invited to participate in VPR: a 10 week exercise programme delivered twice-weekly for one hour. Data were collected at baseline (BL) and post VPR (10 weeks): Kings Brief Interstitial Lung Disease (K-BILD), Exercise capacity (6-minute walk test (6MWT) or 1-minute sit-to-stand (STS)) and Physical Activity. Physical activity was measured with a triaxial accelerometer for seven days. Screening, recruitment, adherence and safety data were collected.
RESULTS: 68 people were screened for this study. N = 16 participants were recruited to the study. There was one dropout. N = 15 completed VPR. All results reported in mean (standard deviation) (SD). Participants attended 18.1(2.0) of the 20 sessions. No adverse events were detected. The mean age of participants was 71.5(11.5) years, range: 47-95 years; 7 M:9 F. Mean (SD) FEV1 2.3(0.3)L, FVC 2.8(0.7)L. No statistically significant changes were observed in outcome measures apart from exercise capacity. Light physical activity increased from 152(69.4) minutes per day (n = 16) to 161.9(88.7) minutes per day (n = 14), mean change (SD) (CI) p-value: 9.9 (39.8) [-12.3 to 30.9] p = 0.4. Moderate-to-vigorous physical activity increased from 19.1(18.6) minutes per day (n = 16) to 25.7(28.3) minutes per day (n = 14), mean change (SD) (CI) p-value: 6.7 (15.5) [-2.1 to 15.1] p = 0.1. Step count increased from 3838(2847) steps per day (n = 16) to 4537(3748) steps per day (n = 14), mean change (SD) (CI) p-value: 738 (1916) [-419.3 to 1734.6] p = 0.2. K-BILD (n = 15) increased from 55.1(7.4) at BL to 55.7(7.9) post VPR mean change (SD) [95% confidence interval] (CI) p-value: 1.7(6.5) [-1.7 to 5.3], p = 0.3. 6MWT (n = 5) increased from 361.5(127.1) to 452.2(136.1) meters, mean change (SD) (CI) p-value: 63.7 (48.2) [-3.8 to 123.6], p = 0.04 and 1-minute STS increased from 17.6(3.0) (n = 11) to 23.7(6.3) (n = 10), mean change (SD) (CI) p-value 5.8 (4.6) [2.6 to 9.1], p = 0.003.
CONCLUSION: VPR can improve physical activity in people with IPF. A number of important feasibility issues included recruitment, retention, adherence and safety have been reported which are crucial for future research in this area. A fully powered trial is needed to determine the response of people with IPF to PR with regard to physical activity.
PMID:38698361 | DOI:10.1186/s12890-024-03030-9
<sup>99m</sup>Tc-labeled FAPI compounds for cancer and inflammation: from radiochemistry to the first clinical applications
EJNMMI Radiopharm Chem. 2024 May 2;9(1):36. doi: 10.1186/s41181-024-00264-0.
ABSTRACT
BACKGROUND: In recent years, fibroblast activating protein (FAP), a biomarker overexpressed by cancer-associated fibroblasts, has emerged as one of the most promising biomarkers in oncology. Similarly, FAP overexpression has been detected in various fibroblast-mediated inflammatory conditions such as liver cirrhosis and idiopathic pulmonary fibrosis. Along this trajectory, FAP-targeted positron emission tomography (PET), utilizing FAP inhibitors (FAPi) labeled with positron emitters, has gained traction as a powerful imaging approach in both cancer and inflammation. However, PET represents a high-cost technology, and its widespread adoption is still limited compared to the availability of gamma cameras. To address this issue, several efforts have been made to explore the potential of [99mTc]Tc-FAPi tracers as molecular probes for imaging with gamma cameras and single photon emission computed tomography (SPECT).
MAIN BODY: Several approaches have been investigated for labeling FAPi-based compounds with 99mTc. Specifically, the mono-oxo, tricarbonyl, isonitrile, and HYNIC strategies have been applied to produce [99mTc]Tc-FAPi tracers, which have been tested in vitro and in animal models. Overall, these labeling approaches have demonstrated high efficiency and strong binding. The resulting [99mTc]Tc-FAPi tracers have shown high specificity for FAP-positive cells and xenografts in both in vitro and animal model studies, respectively. However, the majority of [99mTc]Tc-FAPi tracers have exhibited variable levels of lipophilicity, leading to preferential excretion through the hepatobiliary route and undesirable binding to lipoproteins. Consequently, efforts have been made to synthesize more hydrophilic FAPi-based compounds to improve pharmacokinetic properties and achieve a more favorable biodistribution, particularly in the abdominal region. SPECT imaging with [99mTc]Tc-FAPi has yielded promising results in patients with gastrointestinal tumors, demonstrating comparable or superior diagnostic performance compared to other imaging modalities. Similarly, encouraging outcomes have been observed in subjects with gliomas, lung cancer, breast cancer, and cervical cancer. Beyond oncological applications, [99mTc]Tc-FAPi-based imaging has been successfully employed in myocardial and idiopathic pulmonary fibrosis.
CONCLUSIONS: This overview focuses on the various radiochemical strategies for obtaining [99mTc]Tc-FAPi tracers, highlighting the main challenges encountered and possible solutions when applying each distinct approach. Additionally, it covers the preclinical and initial clinical applications of [99mTc]Tc-FAPi in cancer and inflammation.
PMID:38695960 | DOI:10.1186/s41181-024-00264-0
Interstitial Lung Abnormalities
Surg Pathol Clin. 2024 Jun;17(2):215-225. doi: 10.1016/j.path.2023.11.007. Epub 2023 Dec 20.
ABSTRACT
Interstitial lung abnormalities (ILA) is a radiographic term, which has recently undergone clarification of definition with creation of 3 subtypes. ILA is defined as incidental identification of computed tomography abnormalities in a patient who is not suspected of having an interstitial lung disease (ILD). A subset of ILA may progress to clinically significant ILD and is associated with morbidities not related to progression such as an increased incidence of sepsis-related acute respiratory distress syndrome (ARDS). ILA has been associated with an increased incidence of treatment-related complications in patients with lung cancer. Information on corresponding histology is limited; knowledge gaps exist concerning optimal patient management.
PMID:38692806 | DOI:10.1016/j.path.2023.11.007
Pirfenidone and nintedanib exert additive antifibrotic effects by the SPP1-AKT pathway in macrophages and fibroblasts
Biochem Biophys Res Commun. 2024 Apr 26;716:150020. doi: 10.1016/j.bbrc.2024.150020. Online ahead of print.
ABSTRACT
Idiopathic pulmonary fibrosis (IPF) is a chronic and progressive disease with high mortality rates. It has been shown that pirfenidone (PFD) and nintedanib (Ofev) can slow down the decline in lung function of IPF patients, but their efficacy remains suboptimal. Some studies have suggested that the combination of PFD and Ofev may yield promising results. However, there is a lack of research on the combined application of these two medications in the treatment of IPF. A mouse model of bleomycin-induced (BLM) pulmonary fibrosis was established to investigate the impact of combination therapy on pulmonary fibrosis of mice. The findings demonstrated a significant reduction in lung tissue damage in mice treated with the combination therapy. Subsequent transcriptome analysis identified the differential gene secreted phosphoprotein 1 (SPP1), which was found to be associated with macrophages and fibroblasts based on multiple immunofluorescence staining results. Analysis of a phosphorylated protein microarray indicated that SPP1 plays a regulatory role in macrophages and fibroblasts via the AKT pathway. Consequently, the regulation of macrophages and fibroblasts in pulmonary fibrosis by the combination of PFD and Ofev is mediated by SPP1 through the AKT pathway, potentially offering a novel therapeutic option for IPF patients. Further investigation into the targeting of SPP1 for the treatment of pulmonary fibrosis is warranted.
PMID:38692011 | DOI:10.1016/j.bbrc.2024.150020
Chemokine receptor PET imaging: Bridging molecular insights with clinical applications
Nucl Med Biol. 2024 Apr 18;134-135:108912. doi: 10.1016/j.nucmedbio.2024.108912. Online ahead of print.
ABSTRACT
Chemokine receptors are important components of cellular signaling and play a critical role in directing leukocytes during inflammatory reactions. Their importance extends to numerous pathological processes, including tumor differentiation, angiogenesis, metastasis, and associations with multiple inflammatory disorders. The necessity to monitor the in vivo interactions of cellular chemokine receptors has been driven the recent development of novel positron emission tomography (PET) imaging agents. This imaging modality provides non-invasive localization and quantitation of these receptors that cannot be provided through blood or tissue-based assays. Herein, we provide a review of PET imaging of the chemokine receptors that have been imaged to date, namely CXCR3, CXCR4, CCR2, CCR5, and CMKLR1. The quantification of these receptors can aid in understanding various diseases, including cancer, atherosclerosis, idiopathic pulmonary fibrosis, and acute respiratory distress syndrome. The development of specific radiotracers targeting these receptors will be discussed, including promising results for disease diagnosis and management. However, challenges persist in fully translating these imaging advancements into practical therapeutic applications. Given the success of CXCR4 PET imaging to date, future research should focus on clinical translation of these approaches to understand their role in the management of a wide variety of diseases.
PMID:38691942 | DOI:10.1016/j.nucmedbio.2024.108912
A pipeline for senolytics
J Clin Invest. 2024 May 1;134(9):e180558. doi: 10.1172/JCI180558.
ABSTRACT
There is intense interest in identifying compounds that selectively kill senescent cells, termed senolytics, for ameliorating age-related comorbidities. However, screening for senolytic compounds currently relies on primary cells or cell lines where senescence is induced in vitro. Given the complexity of senescent cells across tissues and diseases, this approach may not target the senescent cells that develop under specific conditions in vivo. In this issue of the JCI, Lee et al. describe a pipeline for high-throughput drug screening of senolytic compounds where senescence was induced in vivo and identify the HSP90 inhibitor XL888 as a candidate senolytic to treat idiopathic pulmonary fibrosis.
PMID:38690734 | DOI:10.1172/JCI180558
Survival and Lung Function Changes in Hypersensitivity Pneumonitis According to Radiological Phenotypes Compared With Idiopathic Pulmonary Fibrosis
Cureus. 2024 Mar 31;16(3):e57307. doi: 10.7759/cureus.57307. eCollection 2024 Mar.
ABSTRACT
INTRODUCTION: The main objective of this study was to estimate survival and changes in lung function in patients with chronic hypersensitivity pneumonitis (HP), both fibrotic (f-HP) and nonfibrotic (nf-HP), and to compare them with those in patients with idiopathic pulmonary fibrosis (IPF).
METHODS: HP was diagnosed based on antigen exposure, HRCT (high-resolution CT scan), BAL (bronchoalveolar lavage), and histology. According to HRCT, HP was classified into fibrotic and non-fibrotic phenotypes. In most cases, IPF was diagnosed based on HRCT findings.
RESULTS: We identified 84 patients: 46 with IPF, 18 with f-HP, and 20 with nf-HP. Five-year survival was 23.9% in IPF, 72% in f-HP, and 100% in nf-HP (p <0.0001). Honeycombing was associated with decreased survival in IPF (p <0.001) and in f-HP (p <0.0001). The mean loss of FVC (forced vital capacity) % pred. (percent predicted) was -18.3% in IPF (p =0.001), -4.8% in f-HP, and -6.0% in nf-HP. The mean change in DLCO (diffusion capacity for carbon monoxide) % pred. was -10.2% in IPF (p <0.002), -0.5% in f-HP, and +1.9% in nf-HP. The agreement between radiological phenotypes and histology in HP was 89.6%.
CONCLUSIONS: We found shorter survival in IPF, followed by f-HP, and nf-HP. Over time, we did not find significant changes in FVC% pred. or DLCO% pred. in HP, while a significant decline in IPF was noted. In HP, we found strong agreement between radiological phenotypes and histology. Radiological signs suggestive of lung fibrosis in HP were reliable for the diagnosis of f-HP and seem to have intrinsic prognostic value.
PMID:38690457 | PMC:PMC11059194 | DOI:10.7759/cureus.57307
Incidence, prevalence and mortality of idiopathic pulmonary fibrosis in England from 2008 to 2018: a cohort study
Thorax. 2024 Apr 30:thorax-2023-220887. doi: 10.1136/thorax-2023-220887. Online ahead of print.
ABSTRACT
BACKGROUND: Owing to discrepancies in methodologies and how idiopathic pulmonary fibrosis (IPF) is diagnosed it is challenging to establish a consistent understanding of the disease burden In the UK, over 10 years ago, the incidence and prevalence of IPF were reported as 2.8-8.7 per 100 000 person-years (from 2000 to 2012) and 39 per 100 000 persons (in 2012), respectively. Here, we estimated the incidence and prevalence of IPF in England from 2008 to 2018 and investigated IPF mortality.
METHODS: Using Clinical Practice Research Datalink Aurum and Hospital Episode Statistics (HES) linked datasets, we estimated incidence and prevalence using four validated diagnostic-code-based algorithms. Using the registered number of deaths (from Office of National Statistics) with the underlying cause being recorded as IPF, we estimated IPF mortality for the same period.
RESULTS: Using Aurum-based definitions, incidence increased over time by 100% for Aurum narrow (3-6.1 per 100 000 person-years) and by 25% for Aurum broad (22.4-28.6 per 100 000 person-years). However, using HES-based definitions showed a decrease in incidence over the same period and lay between the two extremes derived for Aurum-based definition. IPF mortality in 2018 was 7.9 per 100 000 person-years and increased by 53% between 2008 and 2018.
INTERPRETATION: When using best-case definitions, incidence rose throughout the study period. Scaling this to England's population (2018), our best estimate would be in the range of 8000-9000 new cases per year which is higher than previously reported estimates (5000-6000). This increased burden in the new cases of IPF each year impacts future health service planning and resource allocation.
PMID:38688708 | DOI:10.1136/thorax-2023-220887