Collagen Deposition In Extracellular Matrix Research Articles

Abstract PO4-26-03: Collagen deposition in the breast cancer microenvironment correlates with ER-positive, Histological Grade I and low proliferation tumors

Abstract Breast cancer is a highly heterogeneous neoplasm both at the molecular and histological levels. Breast cancer cells present extremely high levels of genetic heterogeneity concerning mutational burden, copy number variations (CNVs) and epigenetic signatures. While this level of heterogeneity is well established, other layers of heterogeneity, such as tumor microenvironment (TME) heterogeneity, remains to be elucidated. TME in breast cancer is an intricate network encompassing tumor cells, “normal” stroma cells such as fibroblasts, lymphocytes, and a plethora of extracellular matrix (ECM) proteins produced either by cancer cells or stromal cells. These three interacting modules (cancer cells, stromal cells and the ECM) can affect each other in a reciprocal way with profound effects on patient prognosis and treatment outcome. Major protein components of the TME are ECM-related collagens, that are produced by breast cancer cells or/and cancer associated fibroblasts. The ECM collagen in breast cancer, that is mainly composed of collagen types I, III and V, has multiple roles modulating tumor growth, cancer cell invasiveness and metastasis. Here by Masson Trichrome and Immunohistochemistry/Aniline Blue co-stains for collagen fibers and proliferation index (Ki-67) in breast cancer FFPE tissue samples, we identified a statistically significant correlation between collagen deposition and Estrogen Receptor (ER)) status (p< 0.05, proliferation index (p< 0.01) and histological Grade (p=0.01). Further, in order to expand and support our findings, we analyzed the METABRIC study through the cBioPortal hub in relevance to collagen genes and multiple clinicopathological parameters. We were able to identify a coregulated subset of collagen genes that presented a positive correlation with ER-positive (p< 10−10, q< 10−10), low proliferating (p< 10−10, q< 10−10), Grade I (p=2.35e−9, q< 1.07e−8) group of breast cancer cases, supporting our findings. In addition, analyses of collagen-high patients from the METABRIC study indicated that most cases presented with PIK3CA, CBFB and MAP3K1 mutations, while through the g.Profiler software we identified collagen-high relevant gene signatures that encompassed gene ontology terms related to tissue development, extracellular matrix organization and cell migration. Collectively, our preliminary results indicate that ECM collagen deposition in breast cancer is characteristic of low-grade tumors with a better differentiation and possibly with a favorable prognosis. Citation Format: Angelos Koutras, Chaido Sirinian, Olga Bogri, Martha Nifora, Maria Theakou, Soren Degn, Ioannis Mouratidis, Dimitrios Chaniotis, Stavros Peroukidis, Ilias Georgakopoulos-Soares, Anastasios Papanastasiou. Collagen deposition in the breast cancer microenvironment correlates with ER-positive, Histological Grade I and low proliferation tumors [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO4-26-03.

Post-myocardial infarction fibrosis: Pathophysiology, examination, and intervention.

Cardiac fibrosis plays an indispensable role in cardiac tissue homeostasis and repair after myocardial infarction (MI). The cardiac fibroblast-to-myofibroblast differentiation and extracellular matrix collagen deposition are the hallmarks of cardiac fibrosis, which are modulated by multiple signaling pathways and various types of cells in time-dependent manners. Our understanding of the development of cardiac fibrosis after MI has evolved in basic and clinical researches, and the regulation of fibrotic remodeling may facilitate novel diagnostic and therapeutic strategies, and finally improve outcomes. Here, we aim to elaborate pathophysiology, examination and intervention of cardiac fibrosis after MI.

Long-term cadmium exposure induces chronic obstructive pulmonary disease-like lung lesions in a mouse model

Accumulating evidences demonstrate that long-term exposure to atmospheric fine particles and air pollutants elevates the risk of chronic obstructive pulmonary disease (COPD). Cadmium (Cd) is one of the important toxic substances in atmospheric fine particles and air pollutants. In this study, we aimed to establish a mouse model to evaluate whether respiratory Cd exposure induces COPD-like lung injury. Adult male C57BL/6 mice were exposed to CdCl2 (10 mg/L, 4 h per day) by inhaling aerosol for either 10 weeks (short-term) or 6 months (long-term). The mean serum Cd concentration was 6.26 μg/L in Cd-exposed mice. Lung weight and coefficient were elevated in long-term Cd-exposed mice. Pathological scores and alveolar destructive indices were increased in long-term Cd-exposed mouse lungs. Mean linear intercept and airway wall thickness were accordingly elevated in Cd-exposed mice. Inflammatory cell infiltration was obvious and inflammatory cytokines, including TNF-α, IL-1β, IL-6, IL-8, IL-10 and TGF-β, were up-regulated in Cd-exposed mouse lungs. α-SMA, N-cadherin and vimentin, epithelial-mesenchymal transition markers, and extracellular matrix collagen deposition around small airway, determined by Masson's trichrome staining, were shown in Cd-exposed mouse lungs. COPD-characteristic lung function decline was observed in long-term Cd-exposed mice. These outcomes show that long-term respiratory exposure to Cd induces COPD-like lung lesions for the first time.

Gelatinized PLCL Electrospun Membrane for the Prevention of Postoperative Abdominal Adhesion Through Fibrinolysis Activation

AbstractAbdominal adhesion is a common complication after surgery, which causes pain to patient and increases the risks of reoperation. Electrospinning polyester membrane serving as a physical barrier is used for preventing abdominal adhesion; however, the efficacy is limited due to the lacking of bioactivity necessary for antiadhesion. Here, hydrophobic poly(l‐lactide‐co‐caprolactone) (PLCL) electrospinning membranes are hydrophilized with photo‐crosslinked methacrylic anhydride gelatin (GelMA) hydrogel for postoperative abdominal adhesion prevention. The composite membranes show fibrous network architecture, good cytocompatibility, and hydrophilicity than commercial poly(d,l‐lactide acid) (PDLLA) film. Importantly, the composite membrane provides superior antiadhesion effect over PLCL membrane alone or commercial PDLLA film, against abdominal wall–cecum adhesion models in Sprague Dawley (SD) rats. The underlying mechanism is that PLCL/GelMA membrane successfully promotes the secretion of matrix metalloproteinases 9 (MMP‐9) that can reduce the collagen deposition in extracellular matrix (ECM). Furthermore, the composite membrane significantly upregulates the expression of tissue‐type plasminogen activator (t‐PA) and downregulates the production of plasminogen activator inhibitor‐1 (PAI‐1), leading to the activation of fibrinolytic system, which inhibits the formation of adhesive tissues. Collectively, gelatinized PLCL electrospun membrane is a promising bioactive barrier for preventing postsurgery abdominal adhesions.

Increased expression of latent TGF-β-binding protein 4 affects the fibrotic process in scleroderma by TGF-β/SMAD signaling

Scleroderma is a fibrosis-related disorder characterized by cutaneous and internal organ fibrosis, and excessive collagen deposition in extracellular matrix (ECM) is a major cause of fibrosis. Transforming growth factor-β (TGF-β)/SMAD signaling has a central role in the pathogenesis of fibrosis by inducing abnormal collagen accumulation in ECM, and latent TGF-β-binding protein 4 (LTBP-4) affects the secretion of latent TGF-β to ECM. A previous study indicated that bleomycin (BLM) treatment increased LTBP-4 expression in lung fibroblasts of Thy-1 knockout mice with lung fibrosis, and LTBP-4 further promoted TGF-β bioavailability as well as SMAD3 phosphorylation. However, the expression and function of LTBP-4 in human scleroderma remain unclear. We aimed to investigate the potential role of LTBP-4 in scleroderma through clinical, in vivo and in vitro studies. LTBP-4 and TGF-β expressions were significantly upregulated in systemic scleroderma (SSc) patients' plasma compared with normal controls (LTBP-4, 1,215±100.2 vs 542.8±41.7 ng/ml, P<0.0001; TGF-β, 1.5±0.2 vs 0.7±0.1 ng/ml, P=0.0031), while no significant difference was found between localized scleroderma (LSc) and normal controls. The plasma concentrations of LTBP-4 and TGF-β were even higher in SSc patients with lung fibrosis (LTBP-4, 1462± 137.3 vs 892.8±113.4 ng/ml, P=0.0037; TGF-β, 2.0±0.4 vs 0.9±0.2 ng/ml, P=0.0212) and esophagus involvement (1390±134.4 vs 940.7±127.0 ng/ml, P=0.0269; TGF-β, 1.9±0.3 vs 0.9±0.2 ng/ml, P=0.0426). The area under receiver operating characteristics (ROC) curve of LTBP-4 was 0.86. Immunohistochemistry measurement also demonstrated a higher LTBP-4 expression in sclerotic skin tissue of LSc and SSc compared with normal controls. More positive fibroblasts were also found in BLM-induced scleroderma mouse model than the saline-treated group. In in vitro studies, knockdown of LTBP-4 in SSc skin fibroblasts prominently reduced downstream COL1A1, COL1A2, and COL3A1 mRNA level by 84%, 82%, and 43%, respectively, and other fibrosis-related genes' expression were also decreased. Furthermore, extracellular TGF-β level and the SMAD2/3 phosphorylation were inhibited through LTBP-4 knockdown treatment, suggesting that the knockdown of LTBP-4 reduced the collagen expression through TGF-β/SMAD signaling pathway. Taken together, these data suggest that LTBP-4 affects fibrotic process in scleroderma, and the high expression of LTBP-4 in SSc plasma may serve as a clinical biomarker in diagnosing this disease. In addition, this study also lays the theoretical foundation for targeting LTBP-4 as treatment of scleroderma.

Mesenchymal Stem Cells and Idiopathic Pulmonary Fibrosis. Potential for Clinical Testing

Idiopathic pulmonary fibrosis (IPF) is a progressive, debilitating, and fatal lung disease characterized by interstitial fibrosis with decreasing lung volumes and hypoxemic respiratory failure. The prognosis for patients with IPF is poor and the quest to find effective therapies has been unsuccessful. Despite several clinical trials over the past decade, there are no U.S. Food and Drug Administration-approved treatments for patients with IPF and thus no standard of care. In terms of pathogenesis, IPF is characterized by alveolar epithelial cell injury and activation with interstitial inflammation, fibroblast proliferation with extracellular matrix collagen deposition, and loss of lung function. Because mesenchymal stem cells (MSCs) home to sites of injury, inhibit inflammation, and contribute to epithelial tissue repair, their use has been suggested as a therapy for the treatment of IPF. MSCs have potential as a novel therapeutic agent in multiple diseases and they have been safely administered in a number of clinical trials. Some, but not all, preclinical studies in animal models of lung fibrosis suggest that MSCs might be effective in the treatment of IPF. Given the safety and ease of MSC administration in other patient populations, the results in preclinical animal models of IPF, and the major need for novel therapeutic options in this devastating disease, we propose that carefully designed clinical trials of MSCs for the treatment of patients with IPF are appropriate. Establishing safety in the setting of IPF is the first priority in early clinical trials followed by clinical and biological measures of efficacy.

Adenosine A2A Receptor: A Target for Regulating Renal Interstitial Fibrosis in Obstructive Nephropathy

Renal interstitial fibrosis (RIF) is the common pathological process of chronic kidney diseases leading inevitably to renal function deterioration. RIF and its preceding epithelial-mesenchymal transition (EMT) are commonly triggered by an early occurring renal inflammation. However, an effective approach to prevent EMT and RIF is still lacking and of urgent need. Recently, the adenosine A2A receptor (A2AR) emerges as a novel inflammation regulator, therefore manipulation of A2AR may suppress the EMT process and as such protect against RIF. To test this hypothesis we applied a unilateral ureteral obstruction (UUO) model of RIF on A2AR knockout mice and their wild-type littermates, combined with the intervention of a selective A2AR agonist, CGS 21680. On days 3, 7 and 14 post-UUO we evaluated the effects of A2AR manipulation on the molecular pathological progresses of RIF, including the cellular component of interstitial infiltration, expression of profibrotic factors, cellular biomarkers of EMT, and collagen deposition of extracellular matrix. Our data demonstrated that activation of A2AR significantly suppressed the deposition of collagen types I and III, reduced the infiltration of CD4+ T lymphocytes, and attenuated the expression of TGF-β1 and ROCK1, which in turn inhibited and postponed the EMT progress. Conversely, genetic inactivation of A2AR exacerbated the aforementioned pathological processes of UUO-induced RIF. Together, activation of A2AR effectively alleviated EMT and RIF in mice, suggesting A2AR as a potential therapeutic target for the treatment of RIF.

Prolonged allergen challenge in a guinea pig model of allergic rhinitis leads to nasal mucosa remodeling

The aim of this study was to use a guinea pig model of prolonged allergic-induced rhinitis to characterize the feature of nasal mucosa remodeling. Forty-eight male Hartley guinea pigs were randomly divided into six groups: allergen challenged groups (Group OVA(2w) , Group OVA(6w) and Group OVA(12w)) and control groups respectively (Group Sal(2w), Group Sal(6w) and Group Sal(12w)). Each group had 8 guinea pigs. To develop a guinea pig model of nasal mucosa remodeling, ovalbumin-sensitized guinea pigs were repeatedly challenged with allergen twice a week from two weeks to 12 weeks. Matched control groups were challenged with physiological saline. Nasal lavage was performed 24 hours after the last intranasal challenge. Then nasal mucosa were obtained. HE, AB-PAS, MT, and immunohistochemical staining against transforming growth factor-beta1 (TGF-beta1) were performed. Eosinophil cationic protein (ECP) and OVA-special IgE (OVA-sIgE) were detected by ELISA in nasal lavage fluid. (1) The levels of OVA-sIgE in nasal lavage fluid in Group OVA(6w) and Group OVA(12w) were significantly different from Group OVA(2w), while the levels of ECP had no significant difference among the experiment groups. The levels of OVA-sIgE and ECP in experiment groups were significantly different from control groups respectively (P < 0.01). (2) Grade 0 and Grade 1 of epithelial damage were significantly different in Group OVA(6w) and Group OVA(12w) when compared with from Group OVA(2w) (P < 0.01). At the same time, Grade 0 and Grade 1 of epithelial damage were statistically different in the experiment groups when compared with the respectively control groups (P < 0.05). (3) Goblet gland hyperplasia and collagen deposit within the extracellular matrix (ECM) were easily found in Group OVA(6w) and Group OVA(12w) compared with Group OVA(2w) (P < 0.01). The number of goblet gland and the ratio of collagen deposit were statistically more in Group OVA(6w) and Group OVA(12w) than in Group Sal(6w) and Group Sal(12w) (P < 0.05). That feature of the ratio of collagen deposit did not show in Group OVA(2w) versus Group Sal(2w). (4) Increased TGF-beta1 expressions were observed in Group OVA(6w) and Group OVA(12w) compared with Group OVA(2w) (P < 0.01). Those increasing expressions were also observed in experiment groups rather than in the respectively control groups (P < 0.01). Epithelial damage, goblet cells hyperplasia and collagen deposition in ECM were observed as the features of remodeling in this guinea pig model of allergic rhinitis under prolonged allergen challenge. Epithelial damage, excessive expression of related cytokines and enhancement activity of enzymes were observed in early time after challenge of allergen. The features of goblet cells hyperplasia and collagen deposition in ECM were observed at a later stage.

Development and Application of Chymase Inhibitors: Development of a Chymase Inhibitor: Pharmacological Characterization of a Chymase Inhibitor in Inflamed Tissue Remodeling and Fibrosis

Chymase, a chymotrypsin-like serine protease, has not only alternative angiotensin II-generating activity but also various activities involving inflammatory responses. However, little is known of its contribution to physiological functions. Therefore, chymase inhibitors are thought to be potentially useful as tools for elucidating the physiological functions of chymase and therapeutic agents. Within the last five years, many patents on non-peptide chymase inhibitors have been published. We developed a potent non-peptide chymase inhibitor BCEAB (4-[1-[[bis-(4-methyl-phenyl)-methy]-carbamoyl]-3-(2-ethoxy-benzyl)-4-oxo-azetidine-2-yloxy]-benzoic acid) and examined its effect on inflamed tissue remodeling and fibrosis using a hamster sponge implant model. BCEAB has high inhibitory activity against human chymase but not against angiotensin-converting enzyme, elastase and tryptase. In the hamster sponge implant model, oral administration of BCEAB for 15 days dose-dependently suppressed both the dry weight of granuloma tissues in the sponge discs and the amounts of hydroxyproline in the tissues gradually increased during the experimental period. These results suggest that chymase, at least in part, participates in the growth of granuloma tissues of inflammatory regions by stimulating fibroblast growth and extracellular matrix collagen deposition. Chymase inhibitors for oral administration, such as BCEAB, might be useful for clarifying the pathophysiological roles of chymase in vivo.