Effects of pharmacological primary cilium disturbance in the context of in vitro 2D and 3D malignant pleura mesothelioma

Effects of patient pleural effusion fluids on the BBSome components expression of human benign mesothelial cells

Malignant pleural mesothelial cells are affected by the extracellular milieu although such data on benign cells are scarce. Benign cells sense the extracellular environment with the primary cilium (PC) and its molecular complex, the Bardet-Biedl syndrome family of proteins (BBSome), is critical for this process. Here we aimed to assess the changes in BBSome gene expression in ordinary two-dimensional (2-D) and spheroid three-dimensional (3-D) cell cultures after incubation with pleural effusion fluids (PFs) of several etiologies. The benign human mesothelial cells (MeT-5A) were incubated with PF from patients with mesothelioma (Meso-PF), breast cancer (BrCa-PF), hemothorax (Hemo-PF), and congestive heart failure (CHF-PF). Gene expression of BBS1, 2, 4, 5, 7, 9, and 18 was assessed by quantitative real-time PCR (qRT-PCR) to monitor PF-induced gene expression changes. MeT-5A cell migration using the PC-modulating drugs ammonium sulfate (AS) and lithium chloride (LC) during PF incubation was also determined. BBSome gene expression upon influence of BrCa-PF and Hemo-PF was more pronounced in 2-D compared with 3-D, inducing global changes in 2-D. CHF-PF and Meso-PF also induced changes in 2-D but not as many, while in all cases, MeT-5A grown in 3-D were more resistant to the effects of the PF. Meso-PF decreased 2-D cell migration, while the disturbance of PC in all PF cases resulted in decreased cell migration. These data suggest distinct BBSome molecular profile changes in benign mesothelial cells exposed to malignant and benign PF that is different in each case, in both 2-D and 3-D. Cell migration is sensitive to drug disturbance with PC modulators in PF-exposed cells.NEW & NOTEWORTHY Studying mesothelial PC in pleural physiology and pathophysiology is at an early stage. Previously, we have highlighted the role of the PC in mesothelial cell phenotypes as well as the role of BBSome components in the context of benign and malignant mesothelial cell physiology. Here we extended our contributions by providing evidence on the BBSome changes induced in benign mesothelial cells by their exposure to different etiology PFs.

Clinical Perspectives and Novel Preclinical Models of Malignant Pleural Mesothelioma: A Critical Review

Pleural mesothelioma (PM), a rare malignant tumor explicitly associated with asbestos and erionite exposures, has become a global health problem due to limited treatment options and a poor prognosis, in which the median life expectancy varies depending on the method of treatment. However, the importance of early diagnosis is emphasized, and the practical methods have not matured yet. This study provides a critical overview of PM, addressing various aspects like epidemiology, etiology, diagnosis, treatment options, and the potential use of advanced technologies like microfluidic chip-based models for research and diagnosis. It initially begins with fundamentals of clinical aspects and then discusses the identification of disease-specific biomarkers in patients' serum or plasma samples, which could potentially be used for early diagnosis. A detailed investigation of the sophisticated preclinical models is highlighted. Recent three-dimensional (3D) model accomplishments, including microarchitecture modeling by transwell coculture, spheroids, organoids, 3D bioprinting constructs, and ex vivo tumor slices, are discussed comprehensively. On-chip models that imitate physiological processes, such as detection chips and therapeutic screening chips, are assessed as potential techniques. The review concludes with a critical and constructive discussion of the growing interest in the topic and its limitations and suggestions.

Differential effects of biocompatible peritoneal dialysis fluids on human mesothelial and endothelial cells in 2D and 3D phenotypes

INTRODUCTION

Peritoneal dialysis (PD) is a life maintaining treatment in patients with end-stage renal disease. Its chronic application leads to peritoneal mesothelial layer denudation and fibrotic transformation along with vascular activation of inflammatory pathways. The impact of different PD fluids (PDF) on mesothelial and endothelial cell function and repair mechanisms are not comprehensively described.

MATERIALS AND METHODS

Mesothelial (MeT-5A) and endothelial cells (EA.hy926) were cultured in 1:1 ratio with cell medium and different PDF (icodextrin-based, amino acid-based, and glucose-based). Cell adhesion, cell migration, and cell proliferation in 2D and spheroid formation and collagen gel contraction assays in 3D cell cultures were performed.

RESULTS

Cell proliferation and cell-mediated gel contraction were both significantly decreased in all conditions. 3D spheroid formation was significantly reduced with icodextrin and amino acid PDF, but unchanged with glucose PDF. Adhesion was significantly increased by amino acid PDF in mesothelial cells and decreased by icodextrin and amino acid PDF in endothelial cells. Migration capacity was significantly decreased in mesothelial cells by all three PDF, while endothelial cells remained unaffected.

CONCLUSIONS

In 3D phenotypes the effects of PDF are more uniform in both mesothelial and endothelial cells, mitigating spheroid formation and gel contraction. On the contrary, effects on 2D phenotypes are more uniform in the icodextrin and amino acid PDF as opposed to glucose ones and affect mesothelial cells more variably. 2D and 3D comparative assessments of PDF effects on the main peritoneal membrane cell barriers, the mesothelial and endothelial, could provide useful translational information for PD studies.

Changes in expression of mesothelial BBS genes in 2D and 3D after lithium chloride and ammonium sulphate induction of primary cilium disturbance: a pilot study

BACKGROUND

Malignant pleural mesothelioma (MPM), a rare and aggressive pleural tumor, has significant histological and molecular heterogeneity. Primary Cilium (PC), an organelle of emerging importance in malignancies, has been scarcely investigated in MPM. A critical molecular complex for the PC function is the BBSome and here we aimed at assessing its expression patterns in ordinary 2D and spheroid 3D cell cultures.

METHODS

A human benign mesothelial cell line (MeT-5A), MPM cell lines (M14K, epithelioid MPM; MSTO, biphasic MPM), and primary MPM cells (pMPM) were used. Primers specific for the human BBS1, 2, 4, 5, 7, 9, 18 transcripts were designed, and quantitative real-time PCR (qRT-PCR) was done with β-actin as the gene of reference. The relative gene expression across 2D and 3D cultures was analyzed by the expression factor (mean of 1/ΔCt values). With the 2-∆∆Ct method the gene expression fold changes were assessed from qRT-PCR data. Molecular changes using the PC-modulating drugs ammonium sulfate (AS) and lithium chloride (LC) were also determined.

RESULTS

PC was present in all cells used in the study at approximately 15% of the observed area. BBSome transcripts were differentially expressed in different dimensions of cell culture (2D vs. 3D) in all cell lines and pMPM. Treatment with AS and LC affected the expression of the ciliary BBS2 and BBS18 genes in the benign as well as in the MPM cells.

CONCLUSIONS

These data indicate distinct BBSome molecular profiles in human benign and MPM cells cultured in 2D and 3D dimensions and support the notion that PC genes should be investigated as potential MPM therapeutic targets.