Fibrin Deposit on the Peritoneal Surface Serves as a Niche for Cancer Expansion in Carcinomatosis Patients

Mesothelial cell responses to acute appendicitis or small bowel obstruction reactive ascites: Insights into immunoregulation of abdominal adhesion

Previous abdominal surgery (PAS) increases risk of small bowel obstruction (SBO) due to adhesions, and appendectomy (appy) is an independent risk factor for abdominal adhesion-related complications. Peritoneal inflammation, e.g., acute appendicitis (AA), causes formation of reactive ascitic fluid (rA) that activates peritoneum surface mesothelial cells (MCs) to form adhesions. Pathologic adhesions may arise if restoration of MC-regulated fibrinolysis and secretion of glycocalyx (GCX) are disrupted. Proteins affecting these processes may originate from peritoneal rA. This is a prospective observational IRB-approved study at three Level 1 trauma centers where rA is collected prior to surgical intervention for non-perforated AA or adhesiolysis for SBO. Samples from 48 appy and 15 SBO patients were used to treat human MCs and subjected to quantification of 85 inflammatory mediators. Results were compared between patients with surgically naïve abdomens (naïve) and patients with >1 PAS. Select rA caused MCs to form clusters of fibroblastic cells, extracellular matrix fibers (FIB), and secretion of GCX. PAS and naïve patient rA fluids were clustered into "fiber-GCX" (FIB-GCX) groups: highFIB-highGCX, highFIB-lowGCX, noFIB-highGCX, noFIB-lowGCX, and noFIB-noGCX. Between groups, 26 analytes were differentially abundant including innate immune response, wound healing, and mucosal defense proteins. Factors that contributed to the differences between groups were rA-induced highFIB and history of PAS. Overall, PAS patient rA showed a muted immune response compared to rA from naïve patients. Our data suggest that abdominal surgery may negatively impact future immune responses in the abdomen. Further, quantifying immunomodulators in peritoneal rA may lead to the development a personalized approach to post-surgical adhesion treatment and prevention.

Research progress of epithelial-mesenchymal transformation-related transcription factors in peritoneal metastases

Metastasis is the leading cause of mortality in patients with malignant tumors, particularly characterized by peritoneal metastases originating from gastric, ovarian, and colorectal cancers. Regarded as the terminal phase of tumor progression, peritoneal metastasis presents limited therapeutic avenues and is associated with a dismal prognosis for patients. The epithelial-mesenchymal transition (EMT) is a crucial phenomenon in which epithelial cells undergo significant changes in both morphology and functionality, transitioning to a mesenchymal-like phenotype. This transition plays a pivotal role in facilitating tumor metastasis, with transcription factors being key mediators of EMT's effects. Consequently, we provide a retrospective summary of the efforts to identify specific targets among EMT-related transcription factors, aimed at modulating the onset and progression of peritoneal metastatic cancer. This summary offers vital theoretical underpinnings for developing treatment strategies against peritoneal metastasis.

Ascites microenvironment conditions the peritoneal pre-metastatic niche to promote the implantation of ovarian tumor spheroids: Involvement of fibrinogen/fibrin and αV and α5β1 integrins

At least one-third of patients with epithelial ovarian cancer (OC) present ascites at diagnosis and almost all have ascites at recurrence especially because of the propensity of the OC cells to spread in the abdominal cavity leading to peritoneal metastasis. The influence of ascites on the development of pre-metastatic niches, and on the biological mechanisms leading to cancer cell colonization of the mesothelium, remains poorly understood. Here, we show that ascites weakens the mesothelium by affecting the morphology of mesothelial cells and by destabilizing their distribution in the cell cycle. Ascites also causes destabilization of the integrity of mesothelium by modifying the organization of cell junctions, but it does not affect the synthesis of N-cadherin and ZO-1 by mesothelial cells. Moreover, ascites induces disorganization of focal contacts and causes actin cytoskeletal reorganization potentially dependent on the activity of Rac1. Ascites allows the densification and reorganization of ECM proteins of the mesothelium, especially fibrinogen/fibrin, and indicates that it is a source of the fibrinogen and fibrin surrounding OC spheroids. The fibrin in ascites leads to the adhesion of OC spheroids to the mesothelium, and ascites promotes their disaggregation followed by the clearance of mesothelial cells. Both αV and α5β1 integrins are involved. In conclusion ascites and its fibrinogen/fibrin composition affects the integrity of the mesothelium and promotes the integrin-dependent implantation of OC spheroids in the mesothelium.

The role of ANXA1 in the tumor microenvironment

Annexin A1 (ANXA1) is widely expressed in a variety of body tissues and cells and is also involved in tumor development through multiple pathways. The invasion, metastasis, and immune escape of tumor cells depend on the interaction between tumor cells and their surrounding environment. Research shows that ANXA1 can act on a variety of cells in the tumor microenvironment (TME), and subsequently affect the proliferation, invasion and metastasis of tumors. This article describes the role of ANXA1 in the various components of the tumor microenvironment and its mechanism of action, as well as the existing clinical treatment measures related to ANXA1. These findings provide insight for the further design of strategies targeting ANXA1 for the diagnosis and treatment of malignant tumors.

Extracellular fibrin promotes non-small cell lung cancer progression through integrin β1/PTEN/AKT signaling

The extracellular matrix (ECM) has been strongly correlated with cancer progression in various tumor types. However, the specific mechanisms underlying ECM-associated tumor behaviors remain unclear. In this study, we found an enriched distribution of fibrin in tumor tissues obtained from high-grade non-small cell lung cancer (NSCLC) patients. For further investigation, we established an in vitro 3D culture system using fibrin gel and found that NSCLC cells grown in this system exhibited increased stemness and tumorigenesis. Mechanistically, we demonstrated that fibrin facilitated the activation of the phosphatase and tensin homolog (PTEN)/protein kinase B (AKT) signaling pathway through integrin β1. Furthermore, we found that blocking integrin β1 signals enhanced the tumor suppressive effects of chemotherapy, providing a novel approach for clinical therapy for NSCLC.

The role of coagulome in the tumor immune microenvironment

The rising incidence and persistent thrombosis in multiple cancers including those that are immunosuppressive highlight the need for understanding the tumor coagulome system and its role beyond hemostatic complications. Immunotherapy has shown significant benefits in solid organ tumors but has been disappointing in the treatment of hypercoagulable cancers, such as glioblastoma and pancreatic ductal adenocarcinomas. Thus, targeting thrombosis to prevent immunosuppression seems a clinically viable approach in cancer treatment. Hypercoagulable tumors often develop fibrin clots within the tumor microenvironment (TME) that dictates the biophysical characteristics of the tumor tissue. The application of systems biology and single-cell approaches highlight the potential role of coagulome or thrombocytosis in shaping the tumor immune microenvironment (TIME). In-depth knowledge of the tumor coagulome would provide unprecedented opportunities to better predict the hemostatic complications, explore how thrombotic stroma modulates tumor immunity, reexamine the significance of clinical biomarkers, and enable steering the stromal versus systemic immune response for boosting the effectiveness of immune checkpoint inhibitors in cancer treatment. We focus on the role of coagulation factors in priming a suppressive TIME and the huge potential of existing anticoagulant drugs in the clinical settings of cancer immunotherapy.

The tumor immune microenvironment in peritoneal carcinomatosis

One in four patients with colorectal cancer, 40% of gastric cancer patients, and 60% of ovarian cancer patients will develop peritoneal metastases (PM) in the course of their disease. The outcome of patients with widespread PM remains poor with currently available treatments. Despite the relatively common occurrence of PM, little is known on the pathophysiology that drives the peritoneal metastatic cascade. It is increasingly recognized that the stromal components of the peritoneal microenvironment play an essential role in tumor progression. However, little is known about the specific interactions and components of the peritoneal tumor microenvironment, particularly with respect the immune cell population. We summarize the current knowledge of the tumor immune microenvironment (TIME) in peritoneal metastases originating from the three most common origins: ovarian, gastric, and colorectal cancer. Clearly, the TIME is highly heterogeneous and its composition and functional activity differ according to tumor type and, within the same patient, according to anatomical location. The TIME in PM remains to be explored in detail, and further elucidation of their immune contexture may allow biology driven design of novel immune modulating or immune targeting therapies.

Coagulome and the tumor microenvironment: an actionable interplay

Human tumors often trigger a hypercoagulable state that promotes hemostatic complications, including venous thromboembolism. The recent application of systems biology to the study of the coagulome highlighted its link to shaping the tumor microenvironment (TME), both within and outside of the vascular space. Addressing this link provides the opportunity to revisit the significance of biomarkers of hemostasis and assess the communication between vasculature and tumor parenchyma, an important topic considering the advent of immune checkpoint inhibitors and vascular normalization strategies. Understanding how the coagulome and TME influence each other offers exciting new prospects for predicting hemostatic complications and boosting the effectiveness of cancer treatment.

Ultrastructural observation of filtration membrane in cell-free and concentrated ascites reinfusion therapy for malignant ascites

INTRODUCTION

Cell-free and concentrated ascites reinfusion therapy (CART) is used for the treatment of diuretic-resistant ascites. An increase in circuit pressure and clogging of the filtration membrane often occur in CART for malignant ascites.

METHODS

To clarify the precise mechanism of filter clogging, we performed an ultrastructural observation study of the filtration membrane after the filtration of malignant ascites.

RESULTS

The deposition on the filtration membrane was composed of blood cells, fibrin, or both. Cellular deposition was associated with a greater number of blood cells in the original ascites fluid. In contrast, fibrin deposition was associated with higher levels of interleukin-6, α1-antitrypsin, haptoglobin, and fibrinogen/fibrin degradation products.

CONCLUSION

Our results suggest that the specific pathophysiologies of malignancy (such as inflammation or coagulation/fibrinolysis) and characteristics of malignant ascites (highly concentrated and cell-rich) are associated with clogging of the filtration membrane during CART.

Intraperitoneal Chemotherapy for Peritoneal Metastases: Technical Innovations, Preclinical and Clinical Advances and Future Perspectives

(1) Background: Tumors of the peritoneal serosa are called peritoneal carcinosis. Their origin may be primary by primitive involvement of the peritoneum (peritoneal pseudomyxoma, peritoneal mesothelioma, etc.). This damage to the peritoneum can also be a consequence of the dissipation of cancers-in particular, digestive (stomach, pancreas, colorectal, appendix) and gynecological (ovaries) ones in the form of metastases. The aim of the treatment is a maximal reduction of the macroscopic disease called "cytoreduction" in combination with hyperthermic intra-abdominal chemotherapy to treat residual microscopic lesions. (2) Methods: In this narrative review, we fundamentally synthetize the evolution of this process over time and its impact on clinical applications. (3) Results: Over the last past decade, different evolutions concerning both delivery modes and conditions concerning hyperthermic intra-abdominal chemotherapy have been realized. (4) Conclusion: The final objective of these evolutions is the improvement of the global and recurrence-free survival of primary and secondary malignant peritoneal pathologies. However, more large randomized controlled trials are needed to demonstrate the efficacy of such treatments with the help of molecular biology and genetics.

LncRNA HOXA-AS2 promotes glioblastoma carcinogenesis by targeting miR-885-5p/RBBP4 axis

Background

LncRNA HOXA-AS2 has been found in the literature to deteriorate glioblastoma. However, its regulatory mechanism is yet to be fully investigated. Our study focused chiefly on the interaction and role of the HOXA-AS2/miR-885-5p/RBBP4 axis in the development of glioblastoma.

Methods

qRT-PCR analysis was performed to detect the expression of lncRNA, miRNA and mRNA in glioblastoma tissues and cells. Dual-luciferase assay, RIP assay and RNA pull-down assay were later carried out to reveal the interactions among HOXA-AS2, miR-885-5p and RBBP4. After that, CCK-8 assay, BrdU assay, nude mice xenografting assay, western blot assay, and flow cytometry were carried out to analyze the effect of the HOXA-AS2/miR-885-5p/RBBP4 axis on glioblastoma samples.

Results

HOXA-AS2 and RBBP4 were found to be overexpressed in glioblastoma. Experimental results showed that HOXA-AS2 and RBBP4 contributed to the tumorigenesis of glioblastoma cells. However, miR-885-5p was observed to be downregulated in glioblastoma. Findings also indicated that HOXA-AS2 could negatively regulate miR-885-5p, thereby enhancing RBBP4 expression.

Conclusion

Overall, HOXA-AS2 promoted the tumorigenesis of glioblastoma by targeting and regulating miR-885-5p to induce the expression of RBBP4.

Remodeling cancer stemness by collagen/fibronectin via the AKT and CDC42 signaling pathway crosstalk in glioma

Cancer development is a complex set of proliferative progression, which arises in most cases via multistep pathways associated with various factors, including the tumor microenvironment and extracellular matrix. However, the underlying mechanisms of cancer development remain unclear and this study aimed to explore the role of extracellular matrix in glioma progression.

Methods: The expression of type I collagen and fibronectin in tumor tissues from glioma patients was examined by immunofluorescence staining. The correlations between collagen/fibronectin and glioma progression were then analyzed. A 3D collagen/fibronectin cultured system was established for tumor cells culture in vitro. Quantitative, real-time PCR and western blot were used to detect PI3K/ATK and CDC42 signals associated proteins expression in glioma. We used in vitro Cell Counting Kit-8, colony formation, and tumorigenesis assays to investigate the function of PI3K/AKT and CDC42 signals associated proteins. A xenograft glioma mice model was also used to study the anticancer effects of integrin inhibitor in vivo.

Results: Our study demonstrated that type I collagen and fibronectin collaborate to regulate glioma cell stemness and tumor growth. In a 3D collagen/fibronectin culture model, glioma cells acquired tumorigenic potential and revealed strengthened proliferative characteristics. More significantly, collagen/fibronectin could facilitate the activation of PI3K/AKT/SOX2 and CDC42/YAP-1/NUPR1/Nestin signaling pathways via integrin αvβ3, eliciting sustained tumor growth and cancer relapse. Combination of the integrin signaling pathway inhibitor and the chemotherapeutic agent efficiently suppressed glioma cell proliferation and tumorigenic ability.

Conclusion: We demonstrated that type I collagen and fibronectin could collaborate to promote glioma progression through PI3K/AKT/SOX2 and CDC42/YAP-1/NUPR1/Nestin signaling pathways. Blockade of the upstream molecular integrin αvβ3 revealed improved outcome in glioma therapy, which provide new insights for eradicating tumors and reducing glioma cancer relapse.

Injured tissues favor cancer cell implantation via fibrin deposits on scar zones

AIM

Evaluation of fibrin role on cancer cells implantation in injured tissues and studying the molecular mechanism of cancer cell interaction with the peritoneal damage.

MATERIAL AND METHODS

Mouse colon cancer (CT26) and human mesothelial cells (HMCs) were used. CT26 cells were implanted on injured peritoneal zones. Icodextrin was used as a lubricant. For in vitro studies, fibrin clots from human plasma were used. The cell-fibrin interaction was observed by optical, electronic, and confocal microscopies. Aprotinin was used as a plasmin inhibitor. Hemostasis impact quantified by (1) the fibrin degradation product D-Dimer and PAR expression in HMCs; (2) the expression of plasminogen activator (PA) and its inhibitor (PAI-1) in cancer cells by qPCR and in supernatants through ELISA after in vitro HMC incubation with 2U of thrombin for 24 h.

RESULTS

(i) Cancer cell lines were adhered and implanted into the wound area in vivo in both the incision and peeling zones of the peritoneum and on the fibrin network in vitro. (ii) Icodextrin significantly inhibited cancer nodule formation in the scar and the incision or peritoneal damaged zones after surgery. (iii) In in vitro studies, cancer cell interaction with the fibrin clot generated a lysed area, causing an increase in plasmin-dependent fibrinolysis measured by D-dimer levels in the supernatants that was inhibited by aprotinin. (iv) Aprotinin inhibited cell-fibrin interaction and invasion. (v) Thrombin upregulates PAI-1 and downregulates PA expression in HMC.

CONCLUSION

Injured tissues favor cancer cell implantation through generated fibrin. Fibrin-cancer cells adhesion can be inhibited by icodextrin.

Role and Mechanism of Rhizopus Nigrum Polysaccharide EPS1-1 as Pharmaceutical for Therapy of Hepatocellular Carcinoma

Objective: This work is to study the effect of Rhizopus nigrum polysaccharide EPS1-1 on hepatocellular carcinoma (HCC) in vitro and in vivo. Methods: HepG2 and Huh-7 cells and nude mice models of liver cancers were used in this study. The cells and nude mice were treated with EPS1-1 at different concentrations. The CCK8 assays were used to measure the proliferation activities of cells, apoptosis was determined with flow cytometry, cell migration was measured by wound-healing assays, cell invasion was evaluated by Transwell assay, and the survival periods of different groups of tumor-bearing mice were compared. Real-time PCR and Western blot were used to measure the expression levels of mRNAs and proteins of the genes related to proliferation, apoptosis, migration, and invasion. Results: In vitro experiments revealed that when treated with EPS1-1, HepG2 and Huh-7 cell proliferation activities decreased, while there was an increase for the apoptosis rate, and the migration and invasion capabilities were significantly reduced. In vivo experiments showed that EPS1-1 could significantly reduce the tumor growth and lung metastasis of HCC, and prolong the survival periods of tumor-bearing nude mice. Furthermore, EPS1-1 has no apparent damage to the heart, liver, and kidney. Further studies showed that EPS1-1 could affect the expression of proliferation-related genes CCND1 and c-Myc, apoptosis-related genes BAX and Bcl-2, and migration and invasion related genes Vimentin and Slug, thereby affecting the biological process of HCC. Conclusion: EPS1-1 can inhibit the malignant process of HCC in vitro and in vivo, which indicates that EPS1-1 has the potential value of clinical application as chemotherapy or adjuvant in the treatment of liver cancer.

Mesothelial-to-Mesenchymal Transition Contributes to the Generation of Carcinoma-Associated Fibroblasts in Locally Advanced Primary Colorectal Carcinomas

During peritoneal metastasis, cancer cells spread from abdominal solid tumors, disseminate through the peritoneal fluid and attach to and invade through mesothelial cells (MCs) that line the peritoneum. Intestinal adenocarcinomas originating in the mucosa infiltrate the submucosa, muscle layer, and serosa in order to finally colonize the peritoneal cavity. However, the mechanism by which metastatic cells leave the primary tumor and reach the peritoneal cavity has not been previously described. Hence, we investigate whether MCs lining visceral peritoneum, through a mesothelial-to-mesenchymal transition (MMT), are a source of carcinoma-associated fibroblasts (CAFs), which could contribute to cancer progression toward the peritoneal cavity. CAFs detected in biopsies from patients with superficially invasive colorectal cancer differed from locally advanced tumors. An aberrant accumulation of myofibroblasts expressing mesothelial markers was found in the stroma of deeply infiltrative tumors located in the neighborhood of a frequently activated mesothelium. We suggest that MMT is a key event in the early stages of peritoneal dissemination.