An integrative histopathologic clustering model based on immuno-matrix elements to predict the risk of death in malignant mesothelioma

Prognostic significance of inflammation-related and electrolyte laboratory variables in patients with malignant pleural mesothelioma

Objective

Malignant pleural mesothelioma (MPM) is a kind of pleural cancer characterized by low incidence but high invasiveness. There is heterogeneity in survival among patients with MPM. Inflammation-related and electrolyte laboratory variables were previously reported as potential predictors of survival. We evaluated the relationship between overall survival and pre-treatment biomarkers.

Materials and methods

Patients diagnosed with MPM in Beijing Chaoyang Hospital for more than 10 years were screened for this study. All basic, clinical, radiologic and laboratory variables were collected. The COX univariable and multivariable analysis were used to explore prognostic related risk factors.

Results

Ninety patients with MPM were included. The median follow-up of all patients was 57 months [interquartile range (IQR): 27–100 months]. The median survival time was 24 months (IQR: 12–52 months). Univariate survival analyses indicated that age, Eastern Cooperative Oncology Group Performance Status, treatment, erythrocyte sedimentation rate, calcium, lymphocyte, hemoglobin, platelet-to-lymphocyte ratio (PLR), and monocyte-to-white blood cell ratio (MWR) were significantly related to survival. Multivariable analysis demonstrated that age [hazard ratio (HR), 2.548; 95% confidence interval (CI) 1.145–5.666; p = 0.022], calcium (HR, 0.480; 95% CI 0.270–0.855; p = 0.013), PLR (HR, 2.152; 95% CI 1.163–3.981; p = 0.015), and MWR (HR, 3.360; 95% CI 1.830–6.170; p < 0.001) might have a significant impact on the prognosis.

Conclusion

Calcium, MWR, and PLR might be related to the prognosis of MPM patients. Analyzing the relationship between the results of inflammation-related and electrolyte laboratory variables in peripheral blood and prognosis could help clinicians evaluate the situation of patients.

High Expression of SMO and GLI1 Genes with Poor Prognosis in Malignant Mesothelioma

Background

To investigate the value of SMO and GLI1 genes in the hedgehog pathway in malignant mesothelioma specimens. Further study on the expression and prognosis of SMO and GLI1 in malignant mesothelioma tissues and the relationship between the two and the molecular mechanisms of mesothelioma immunity and to further investigate the prognostic value of mesothelioma expression.

Materials and Methods

Immunohistochemistry and RT-qPCR were applied to detect the expression of SMO and GLI1 proteins and mRNA in biopsy specimens and plasma cavity effusion specimens from malignant mesothelioma (n = 130) and benign mesothelial tissues (n = 50) and to analyze the clinicopathological significance and survival risk factors of SMO and GLI1 protein expression in mesothelioma. The mechanisms of mesothelioma cell expression and immune cell infiltration were investigated using bioinformatics methods.

Results

SMO and GLI1 in mesothelioma tissues detected high concordance between the diagnostic results of mesothelioma biopsy specimens and plasma cavity effusion specimens. The expression levels of SMO and GLI1 protein and mRNA in mesothelioma tissues were higher than those in benign mesothelioma tissues. The expression levels of SMO and GLI1 protein were correlated with the age, site, and asbestos exposure history of patients with mesothelioma. The expression levels of SMO and GLI1 protein were correlated with the expressions of ki67 and p53 (P < 0.05). SMO and GLI1 gene expression levels were negatively correlated with good prognosis in mesothelioma patients (P < 0.05). Cox proportional risk model indicated that protein expressions of invasion, lymph node metastasis, distant metastasis, staging, and genes were independent prognostic factors of mesothelioma. The GEPIA database showed the overall survival rate and the disease-free survival rate of mesothelioma patients in the high SMO and GLI1 expression groups; the UALCAN database analysis showed lower SMO expression levels in mesothelioma patients with more pronounced TP53 mutations (P = 0.001); GLI1 gene expression levels were strongly correlated with lymph node metastasis in mesothelioma patients (P = 0.009). Timer database analysis showed that the mechanism of immune cell infiltration was closely related to SMO and GLI1 expression. The degree of immune cell infiltration was strongly correlated with the prognosis of mesothelioma patients (P < 0.05).

Conclusion

The expression levels of both SMO and GLI1 proteins were higher than those of normal mesothelial tissues, and the mRNA expression levels also changed in the same direction. SMO and GLI1 gene expressions in mesothelioma were negatively correlated with age, site of occurrence, and history of asbestos exposure. Positive expression of SMO and GLI1 was negatively correlated with patient survival. The Cox proportional risk model showed that gender, history of asbestos exposure, site of occurrence, SMO, and GLI1 were independent prognostic factors for mesothelioma. The mechanism of immune cell infiltration in mesothelioma is closely related to the gene expression of both and the survival prognosis of mesothelioma patients.

Effects of different fluid management on lung and kidney during pressure-controlled and pressure-support ventilation in experimental acute lung injury

Optimal fluid management is critical during mechanical ventilation to mitigate lung damage. Under normovolemia and protective ventilation, pulmonary tensile stress during pressure-support ventilation (PSV) results in comparable lung protection to compressive stress during pressure-controlled ventilation (PCV) in experimental acute lung injury (ALI). It is not yet known whether tensile stress can lead to comparable protection to compressive stress in ALI under a liberal fluid strategy (LF). A conservative fluid strategy (CF) was compared with LF during PSV and PCV on lungs and kidneys in an established model of ALI. Twenty-eight male Wistar rats received endotoxin intratracheally. After 24 h, they were treated with CF (minimum volume of Ringer's lactate to maintain normovolemia and mean arterial pressure ≥70 mmHg) or LF (~4 times higher than CF) combined with PSV or PCV (VT  = 6 ml/kg, PEEP = 3 cmH2 O) for 1 h. Nonventilated animals (n = 4) were used for molecular biology analyses. CF-PSV compared with LF-PSV: (1) decreased the diffuse alveolar damage score (10 [7.8-12] vs. 25 [23-31.5], p = 0.006), mainly due to edema in axial and alveolar parenchyma; (2) increased birefringence for occludin and claudin-4 in lung tissue and expression of zonula-occludens-1 and metalloproteinase-9 in lung. LF compared with CF reduced neutrophil gelatinase-associated lipocalin and interleukin-6 expression in the kidneys in PSV and PCV. In conclusion, CF compared with LF combined with PSV yielded less lung epithelial cell damage in the current model of ALI. However, LF compared with CF resulted in less kidney injury markers, regardless of the ventilatory strategy.

Fibrosis in Mesothelioma: Potential Role of Lysyl Oxidases

Immunotherapies (such as checkpoint inhibitors) and standard chemotherapies (such as cisplatin) have limitations in the successful treatment of malignant pleural mesothelioma (MPM). Fibrosis is the accumulation of collagen in the extracellular matrix (ECM) of tissues, making them denser than that of healthy tissues and thereby affecting drug delivery and immune cell infiltration. Moreover, fibrosis severely affects the patient's breathing and quality of life. The production of collagen and its assembly is highly regulated by various enzymes such as lysyl oxidases. Many solid tumors aberrantly express the family of lysyl oxidases (LOX/LOXL). This review examines how LOX/LOXLs were found to be dysregulated in noncancerous and cancerous settings, discusses their roles in solid tumor fibrosis and pathogenesis and explores the role of fibrosis in the development and poor clinical outcomes of patients with MPM. We examine the current preclinical status of drugs targeting LOX/LOXLs and how the incorporation of such drugs may have therapeutic benefits in the treatment and management of patients with MPM.

Pulmonary Neuroendocrine Neoplasms Overexpressing Epithelial-Mesenchymal Transition Mechanical Barriers Genes Lack Immune-Suppressive Response and Present an Increased Risk of Metastasis

Typical carcinoids (TC), atypical carcinoids (AC), large cell neuroendocrine carcinomas (LCNEC), and small cell lung carcinomas (SCLC) encompass a bimodal spectrum of metastatic tumors with morphological, histological and histogenesis differences, The hierarchical structure reveals high cohesiveness between neoplastic cells by mechanical desmosomes barrier assembly in carcinoid tumors and LCNEC, while SCLC does not present an organoid arrangement in morphology, the neoplastic cells are less cohesive. However, the molecular mechanisms that lead to PNENs metastasis remain largely unknown and require further study. In this work, epithelial to mesenchymal transition (EMT) transcription factors were evaluated using a set of twenty-four patients with surgically resected PNENs, including carcinomas. Twelve EMT transcription factors (BMP1, BMP7, CALD1, CDH1, COL3A1, COL5A2, EGFR, ERBB3, PLEK2, SNAI2, STEAP1, and TCF4) proved to be highly expressed among carcinomas and downregulated in carcinoid tumors, whereas upregulation of BMP1, CDH2, KRT14 and downregulation of CAV2, DSC2, IL1RN occurred in both histological subtypes. These EMT transcription factors identified were involved in proliferative signals, epithelium desmosomes assembly, and cell motility sequential steps that support PNENs invasion and metastasis in localized surgically resected primary tumor. We used a two-stage design where we first examined the candidate EMT transcription factors using a whole-genome screen, and subsequently, confirmed EMT-like changes by transmission electron microscopy and then, the EMT-related genes that were differentially expressed among PNENs subtypes were predicted through a Metascape analysis by in silico approach. A high expression of these EMT transcription factors was significantly associated with lymph node and distant metastasis. The sequential steps for invasion and metastasis were completed by an inverse association between functional barrier created by PD-L1 immunosuppressive molecule and EMT transcriptional factors. Our study implicates upregulation of EMT transcription factors to high proliferation rates, mechanical molecular barriers disassembly and increased cancer cell motility, as a critical molecular event leading to metastasis risk in PNENs thus emerging as a promising tool to select and customize therapy.

In Situ Overexpression of Matricellular Mechanical Proteins Demands Functional Immune Signature and Mitigates Non-Small Cell Lung Cancer Progression

Non-small cell lung carcinoma (NSCLC) is a complex cancer biome composed of malignant cells embedded in a sophisticated tumor microenvironment (TME) combined with different initiating cell types, including immune cells and cancer-associated fibroblasts (CAFs), and extracellular matrix (ECM) proteins. However, little is known about these tumors’ immune-matricellular relationship as functional and mechanical barriers. This study investigated 120 patients with NSCLC to describe the immune-matricellular phenotypes of their TME and their relationship with malignant cells. Immunohistochemistry (IHC) was performed to characterize immune checkpoints (PD-L1, LAG-3, CTLA-4+, VISTA 1), T cells (CD3+), cytotoxic T cells (CD8⁺, Granzyme B), macrophages (CD68+), regulatory T cells (FOXP3+, CD4+), natural killer cells (CD57+), and B lymphocytes (CD20+), whereas CAFs and collagen types I, III, and V were characterized by immunofluorescence (IF). We observed two distinct functional immune-cellular barriers—the first of which showed proximity between malignant cells and cytotoxic T cells, and the second of which showed distant proximity between non-cohesive nests of malignant cells and regulatory T cells. We also identified three tumor-associated matricellular barriers: the first, with a localized increase in CAFs and a low deposition of Col V, the second with increased CAFs, Col III and Col I fibers, and the third with a high amount of Col fibers and CAFs bundled and aligned perpendicularly to the tumor border. The Cox regression analysis was designed in two steps. First, we investigated the relationship between the immune-matricellular components and tumor pathological stage (I, II, and IIIA), and better survival rates were seen in patients whose tumors expressed collagen type III > 24.89 fibers/mm². Then, we included patients who had progressed to pathological stage IV and found an association between poor survival and tumor VISTA 1 expression > 52.86 cells/mm² and CD3+ ≤ 278.5 cells/mm². We thus concluded that differential patterns in the distribution of immune-matricellular phenotypes in the TME of NSCLC patients could be used in translational studies to predict new treatment strategies and improve patient outcome. These data raise the possibility that proteins with mechanical barrier function in NSCLC may be used by cancer cells to protect them from immune cell infiltration and immune-mediated destruction, which can otherwise be targeted effectively with immunotherapy or collagen therapy.

The Fibrosis-Targeted Collagen/Integrins Gene Profile Predicts Risk of Metastasis in Pulmonary Neuroendocrine Neoplasms

Recently, collagen/integrin genes have shown promise as predictors of metastasis mainly in non-small cell lung cancer and breast cancer. However, it is unknown if these gene expression profiling differ in metastatic potential of pulmonary neuroendocrine neoplasms (PNENs). In this study, we sought to identify differentially expressed collagen/integrin genes in PNENs in order to understand the molecular mechanisms underlying the development of stroma-associated fibrosis for invasion and metastasis. We compared collagen/integrin gene expression profiling between PNE tumors (PNETs) and PNE carcinomas (PNECs) using a two-stage design. First, we used PCR Array System for 84 ECM-related genes, and among them, we found COL1A2, COL3A1, COL5A2, ITGA5, ITGAV, and ITGB1 functionally involved in the formation of the stroma-associated fibrosis among PNENs histological subtypes. Second, we examined the clinical association between the six collagen/integrin genes in tumor tissues from 24 patients with surgically excised PNENs. However, the pathological exam of their resected tissues demonstrated that 10 developed lymph node metastasis and 7 distant metastasis. We demonstrated and validated up regulation of the six fibrogenic genes in PNECs and down regulation in PNETs that were significantly associated with metastasis-free and overall survival (P<0.05). Our study implicates up regulation of fibrogenic genes as a critical molecular event leading to lymph node and distant metastasis in PNENs.

Pathological Characterization of Tumor Immune Microenvironment (TIME) in Malignant Pleural Mesothelioma

Malignant pleural mesothelioma (MPM) is a rare and highly aggressive disease that arises from pleural mesothelial cells, characterized by a median survival of approximately 13-15 months after diagnosis. The primary cause of this disease is asbestos exposure and the main issues associated with it are late diagnosis and lack of effective therapies. Asbestos-induced cellular damage is associated with the generation of an inflammatory microenvironment that influences and supports tumor growth, possibly in association with patients' genetic predisposition and tumor genomic profile. The chronic inflammatory response to asbestos fibers leads to a unique tumor immune microenvironment (TIME) composed of a heterogeneous mixture of stromal, endothelial, and immune cells, and relative composition and interaction among them is suggested to bear prognostic and therapeutic implications. TIME in MPM is known to be constituted by immunosuppressive cells, such as type 2 tumor-associated macrophages and T regulatory lymphocytes, plus the expression of several immunosuppressive factors, such as tumor-associated PD-L1. Several studies in recent years have contributed to achieve a greater understanding of the pathogenetic mechanisms in tumor development and pathobiology of TIME, that opens the way to new therapeutic strategies. The study of TIME is fundamental in identifying appropriate prognostic and predictive tissue biomarkers. In the present review, we summarize the current knowledge about the pathological characterization of TIME in MPM.

Different histological patterns of type-V collagen levels confer a matrices-privileged tissue microenvironment for invasion in malignant tumors with prognostic value

Previous studies have reported a close relationship between type V collagen (Col V) and tumor invasion and motility in both breast cancer (BC) and lung cancer (LC). The present work aims to determine whether the extracellular-matrix (ECM)-defined microenvironment influences patient clinical outcome and investigate to which extent histological patterns of Col V expression in malignant cells have a prognostic effect in patients. To that end, we examined the expression of Col V in the tissues of 174 primary tumors (MM, N = 82; LC, N = 41; and BC, N = 46) by immunohistochemistry. We found: (1) diffuse strong green birefringence in membrane and cytoplasm individualizing malignant cells in MM; (2) a focal and weak birefringence mainly in cytoplasmic membrane involving groups of malignant cells in LC and BC; (3) higher average H-score of Col V in MM than in LC and BC samples; (4) a direct correlation between Col V histologic pattern and TNM stage IV, status and median overall survival; (5) patients with LC in TNM stage I, and Col V ≤ 41.7 IOD/mm2 had a low risk of death and a median survival time more than 20 months; (6) patients with MM in TNM stage IV and Col V > 41.7 IOD/mm2 presented a high risk of death and a median survival time of just 20 months. These findings suggest that high levels of Col V individualizing malignant cells, as observed in MM, and low levels grouping malignant cells, as observed in LC and BC, confers different immune-privileged tissue microenvironment for tumor invasion with impact on prognosis of the patients.

In situ Evidence of Collagen V and Interleukin-6/Interleukin-17 Activation in Vascular Remodeling of Experimental Pulmonary Hypertension

Several studies have reported the pathophysiologic and molecular mechanisms responsible for pulmonary arterial hypertension (PAH). However, the in situ evidence of collagen V (Col V) and interleukin-17 (IL-17)/interleukin-6 (IL-6) activation in PAH has not been fully elucidated. We analyzed the effects of collagen I (Col I), Col V, IL-6, and IL-17 on vascular remodeling and hemodynamics and its possible mechanisms of action in monocrotaline (MCT)-induced PAH. Twenty male Wistar rats were randomly divided into two groups. In the PAH group, animals received MCT 60 mg/kg intraperitoneally, whereas the control group (CTRL) received saline. On day 21, the pulmonary blood pressure (PAP) and right ventricular systolic pressure (RVSP) were determined. Lung histology (smooth muscle cell proliferation [α-smooth muscle actin; α-SMA] and periadventitial fibrosis), immunofluorescence (Col I, Col V, and α-SMA), immunohistochemistry (IL-6, IL-17, and transforming growth factor-beta [TGF-β]), and transmission electron microscopy to detect fibronexus were evaluated. The RVSP (40 ± 2 vs. 24 ± 1 mm Hg, respectively; p < 0.0001), right ventricle hypertrophy index (65 ± 9 and 25 ± 5%, respectively; p < 0.0001), vascular periadventitial Col I and Col V, smooth muscle cell α-SMA+, fibronexus, IL-6, IL-17, and TGF-β were higher in the MCT group than in the CTRL group. In conclusion, our findings indicate in situ evidence of Col V and IL-6/IL-17 activation in vascular remodeling and suggest that increase of Col V may yield potential therapeutic targets for treating patients with PAH.

An integrative histopathologic clustering model based on immuno-matrix elements to predict the risk of death in malignant mesothelioma

Objective

Previous studies have reported a close relationship between malignant mesothelioma (MM) and the immune matricial microenvironment (IMM). One of the major problems in these studies is the lack of adequate adjustment for potential confounders. Therefore, the aim of this study was to identify and quantify risk factors such as IMM and various tumor characteristics and their association with the subtype of MM and survival.

Methods

We examined IMM and other tumor markers in tumor tissues from 82 patients with MM. These markers were evaluated by histochemistry, immunohistochemistry, immunofluorescence, and morphometry. Logistic regression analysis, cluster analysis, and Cox regression analysis were performed.

Results

Hierarchical cluster analysis revealed two clusters of MM that were independent of clinicopathologic features. The high‐risk cluster included MM with high tumor cellularity, high type V collagen (Col V) fiber density, and low CD8⁺ T lymphocyte density in the IMM. Our results showed that the risk of death was increased for patients with MM with high tumor cellularity (OR = 1.63, 95% CI = 1.29‐2.89, P = .02), overexpression of Col V (OR = 2.60, 95% CI = 0.98‐6.84, P = .04), and decreased CD8 T lymphocytes (OR = 1.001, 95% CI = 0.995‐1.007, P = .008). The hazard ratio for the high‐risk cluster was 2.19 (95% CI = 0.54‐3.03, P < .01) for mortality from MM at 40 months.

Conclusion

Morphometric analysis of Col V, CD8⁺ T lymphocytes, and tumor cellularity can be used to identify patients with high risk of death from MM.