Single-cell tumor heterogeneity landscape of hepatocellular carcinoma: unraveling the pro-metastatic subtype and its interaction loop with fibroblasts.

BACKGROUND: Tumor heterogeneity presents a formidable challenge in understanding the mechanisms driving tumor progression and metastasis. The heterogeneity of hepatocellular carcinoma (HCC) in cellular level is not clear. METHODS: Integration analysis of single-cell RNA sequencing data and spatial transcriptomics data was performed. Multiple methods were applied to investigate the subtype of HCC tumor cells. The functional characteristics, translation factors, clinical implications and microenvironment associations of different subtypes of tumor cells were analyzed. The interaction of subtype and fibroblasts were analyzed. RESULTS: We established a heterogeneity landscape of HCC malignant cells by integrated 52 single-cell RNA sequencing data and 5 spatial transcriptomics data. We identified three subtypes in tumor cells, including ARG1+ metabolism subtype (Metab-subtype), TOP2A+ proliferation phenotype (Prol-phenotype), and S100A6+ pro-metastatic subtype (EMT-subtype). Enrichment analysis found that the three subtypes harbored different features, that is metabolism, proliferating, and epithelial-mesenchymal transition. Trajectory analysis revealed that both Metab-subtype and EMT-subtype originated from the Prol-phenotype. Translation factor analysis found that EMT-subtype showed exclusive activation of SMAD3 and TGF-ß signaling pathway. HCC dominated by EMT-subtype cells harbored an unfavorable prognosis and a deserted microenvironment. We uncovered a positive loop between tumor cells and fibroblasts mediated by SPP1-CD44 and CCN2/TGF-ß-TGFBR1 interaction pairs. Inhibiting CCN2 disrupted the loop, mitigated the transformation to EMT-subtype, and suppressed metastasis. CONCLUSION: By establishing a heterogeneity landscape of malignant cells, we identified a three-subtype classification in HCC. Among them, S100A6+ tumor cells play a crucial role in metastasis. Targeting the feedback loop between tumor cells and fibroblasts is a promising anti-metastatic strategy.

Corrigendum: Cigarette smoke restricts the ability of mesenchymal cells to support lung epithelial organoid formation.

[This corrects the article DOI: 10.3389/fcell.2023.1165581.].

Investigation roles of Adamts1 and Adamts5 in scleral fibroblasts under hypoxia and mice with form-deprived myopia.

Scleral hypoxia is considered a trigger in scleral remodeling-induced myopia. Identifying differentially expressed molecules within the sclera is essential for understanding the mechanism of myopia. We developed a scleral fibroblast hypoxia model and conducted RNA sequencing and bioinformatic analysis. RNA interference technology was then applied to knock down targeted genes with upregulated expression, followed by an analysis of COLLAGEN I protein level. Microarray data analysis showed that the expression of Adamts1 and Adamts5 were upregulated in fibroblasts under hypoxia (t-test, p < 0.05). Western blot analysis confirmed increased protein levels of ADAMTS1 and ADAMTS5, and a concurrent decrease in COLLAGEN I in hypoxic fibroblasts. The knockdown of either Adamts1 or Adamts5 in scleral fibroblasts under hypoxia resulted in an upregulation of COLLAGEN I. Moreover, a form-deprivation myopia (FDM) mouse model was established for validation. The sclera tissue from FDM mice exhibited increased levels of ADAMTS1 and ADAMTS5 protein and a decrease in COLLAGEN I, compared to controls. The study suggests that Adamts1 and Adamts5 may be involved in scleral remodeling induced by hypoxia and the development of myopia.

WNT2B high­expressed fibroblasts induce the fibrosis of IBD by promoting NK cells secreting IL-33.

Fibrosis is an important pathological change in inflammatory bowel disease (IBD), but the mechanism has yet to be elucidated. WNT2B high­expressed fibroblasts are enriched in IBD intestinal tissues, although the precise function of this group of fibroblasts remains unclear. This study investigated whether WNT2B high­expressed fibroblasts aggravated intestinal tissue damage and fibrosis. Our study provides evidence that WNT2B high­expressed fibroblasts and NK cells were enriched in colitis tissue of patients with IBD. WNT2B high­expressed fibroblasts secreted wnt2b, which bound to FZD4 on NK cells and activated the NF-κB and STAT3 pathways to enhance IL-33 expression. TCF4, a downstream component of the WNT/ß-catenin pathway, bound to p65 and promoted binding to IL-33 promoter. Furthermore, Salinomycin, an inhibitor of the WNT/ß-catenin pathway, inhibited IL-33 secretion in colitis, thereby reducing intestinal inflammation.Knocking down WNT2B reduces NK cell infiltration and IL-33 secretion in colitis, and reduce intestinal inflammation and fibrosis. In conclusion, WNT2B high­expressed fibroblasts activate NK cells by secreting wnt2b, which activates the WNT/ß-catenin and NF-κB pathways to promote IL-33 expression and secretion, potentially culminating in the induction of colonic fibrosis in IBD. KEY MESSAGES: WNT2B high-expressed fibroblasts and NK cells are enriched in colitis tissue, promoting NK cells secreting IL-33. Wnt2b activates NF-κB and STAT3 pathways promotes IL-33 expression by activating p65 and not STAT3. syndrome TCF4 binds to p65 and upregulates the NF- κB pathway. Salinomycin reduces NK cell infiltration and IL-33 secretion in colitis. Knocking down WNT2B mitigates inflammation and fibrosis in chronic colitis.

Exploring the Molecular Underpinnings of Skin Regeneration and Wound Healing: The Role of Renin Angiotensin.

The aim of this study is to review the role of renin-angiotensin in skin regeneration and wound healing with a focus on molecular mechanisms. Angiotensin receptor type 1 (AT1R) are abundant in the wounded area, and thus, lead to the activation of ERK, STAT1, and STAT3 which can lead to epidermal self-renewal. The expression of Renin Angiotensin System (RAS) components was significantly lower in wounds caused by burning, rather than intact skin, noting that RAS is involved in the re-epithelialization of skin. ERK, STAT and STAT3 are the targets of Ang II, indicating that RAS active components are involved in fibroblast, stem cells and keratinocyte migration. The effect of inhibiting the RAS on wound healing is context-dependent. On one hand, it is suggested that inhibiting RAS during this phase may slow down wound healing speed. On the other hand, studies have shown that RAS inhibition in this phase can lead to α-SMA activation, ultimately accelerating the wound healing process. Most of the investigations indicate that the inhibition of RAS with Angiotensin Receptor Blockers (ARBs) and Angiotensin Converting Enzyme (ACE) plays a significant role in tissue remodeling in the last phase of wound healing. It has been shown that the inhibition of RAS can inhibit scar formation and fibrosis through the downregulation of inflammatory and fibrogenic agents, such as TGF-ß, SMAD2/3, and TAK1, PDGF-BB, and HSP47. To sum up, that local administration of RAS regulators might lead to less scar formation and inflammation in the last phase of wound closure.

Gal-1-mediated cytochrome p450 activation promotes fibroblast into myofibroblast differentiation in pulmonary fibrosis.

Pulmonary fibrosis (PF) results from excessive extracellular matrix (ECM) deposition and tissue remodeling after activation of fibroblasts into myofibroblasts. Abnormally deposited fibrotic ECM, in turn, promotes fibroblast activation and accelerates loss of lung structure and function. However, the molecular mediators and exact mechanisms by which fibrotic ECM promotes fibroblast activation are unclear. In a bleomycin-induced PF mouse model, we found Galectin-1 (Gal-1) expression was significantly increased in lung tissue, and overexpression of Gal-1 plasmid-transfected fibroblasts were activated into myofibroblasts. Using the decellularization technique to prepare decellularized fibrotic ECM and constructing a 3D in vitro co-culture system with fibroblasts, we found that decellularized fibrotic ECM induced a high expression of Gal-1 and promoted the activation of fibroblasts into myofibroblasts. Therefore, Gal-1 has been identified as a pivotal mediator in PF. Further, we found that decellularized fibrotic ECM delivered mechanical signals to cells through the Gal-1-mediated FAK-Src-P130Cas mechanical signalling pathway, while the CYP450 enzymes (mainly involved in CYP1A1, CYP24A1, CYP3A4, and CYP2D6 isoforms) acted as a chemical signalling pathway to receive mechanical signals transmitted from upstream Gal-1, thereby promoting fibroblast activation. The Gal-1 inhibitor OTX008 or the CYP1A1 inhibitor 7-Hydroxyflavone prevented PF in mice and inhibited the role of fibrotic ECM in promoting fibroblast activation into myofibroblasts, preventing PF. These results reveal novel molecular mechanisms of lung fibrosis formation and identify Gal-1 and its downstream CYP1A1 as potential therapeutic targets for PF disease treatmnts.

Single-cell Analysis of Debrided Diabetic Foot Ulcers Reveals Dysregulated Wound Healing Environment in non-Hispanic Blacks.

Diabetic foot ulcer (DFU) is a critical complication of diabetes, but the wound microenvironment and its healing process are not completely understood. In this study, we optimized single-cell profiling from sharp debrided ulcers. Our findings demonstrate that healing-DFUs were significantly enriched with distinct fibroblasts expressing genes related to inflammation (CHI3L1, IL6) and extracellular matrix remodeling (ASPN), validating our previous studies on surgically resected ulcers. The race-focused analysis depicted lower expression of key healing-associated genes such as CHIL3L1, MMP11, and SFRP4 in fibroblasts of non-Hispanic Black (NHB) patients compared to White patients. In cellular communication analysis, healing enriched fibroblasts of NHBs exhibited upregulation of signaling pathways such as WNT while those of White showed IGF and MK pathways upregulation. Our findings advocate race as a risk marker of DFU outcomes, likely reflecting underlying disparities in environmental exposures and access to care that profoundly influence healing markers. Using sharp debrided tissues for single-cell assays, this study highlights the need for in-depth investigations into dysregulated wound healing microenvironments of under-represented racial groups.

Dual targeting chimeric antigen receptor cells enhance antitumour activity by overcoming T cell exhaustion in pancreatic cancer.

BACKGROUND AND PURPOSE: Although our previous data indicated that claudin 18 isoform 2 (CLDN18.2)-targeted chimeric antigen receptor (CAR) T cells displayed remarkable clinical efficacy in CLDN18.2-positive gastric cancer, their efficacy is limited in pancreatic ductal adenocarcinoma (PDAC). The tumour microenvironment (TME) is one of the main obstacles to the efficacy of CAR-T and remodelling the TME may be a possible way to overcome this obstacle. The TME of PDAC is characterized by abundant cancer-related fibroblasts (CAFs), which hinder the infiltration and function of CLDN18.2-targeted CAR-T cells. The expression of fibroblast activation protein alpha (FAP) is an important feature of active CAFs, providing potential targets for eliminating CAFs. EXPERIMENTAL APPROACH: In this study, we generated 10 FAP/CLDN 18.2 dual-targeted CAR-T cells and evaluated their anti-tumour ability in vitro and in vivo. KEY RESULTS: Compared with conventional CAR-T cells, some dual-targeted CAR-T cells showed improved therapeutic effects in mouse pancreatic cancers. Further, dual-targeted CAR-T cells with better anti-tumour effect could suppress the recruitment of myeloid-derived suppressor cells (MDSCs) to improve the immunosuppressive TME, which contributes to the survival of CD8+ T cells. Moreover, dual-targeted CAR-T cells reduced the exhaustion of T cells in transforming TGF-ß dependent manner. CONCLUSION AND IMPLICATIONS: The dual-targeted CAR-T cells obtained enhancement of T effector function, inhibition of T cell exhaustion, and improvement of tumour microenvironment. Our findings provide a theoretical rationale for dual-targeted FAP/CLDN 18.2 CAR-T cells therapy in PDAC.

Wound healing potential and anti-inflammatory action of extracts and compounds of Myrciaria plinioides D. Legrand leaves.

Wounds or chronic injuries are associated with high medical costs so, develop healing-oriented drugs is a challenge for modern medicine. The identification of new therapeutic alternatives focuses on the use of natural products. Therefore, the main goal of this study was to evaluate the healing potential and anti-inflammatory mechanism of action of extracts and the main compounds derived from Myrciaria plinioides D. Legrand leaves. The antimicrobial activity of leaf extracts was analyzed. Cell viability, cytotoxicity and genotoxicity of plant extracts and compounds were also assessed. Release of pro- and anti-inflammatory cytokines and TGF-ß by ELISA, and protein expression was determined by Western Blot. The cell migration and cell proliferation of ethanol and aqueous leaf extracts and p-coumaric acid, quercetin and caffeic acid compounds were also evaluated. The aqueous extract exhibited antibacterial activity and, after determining the safety concentrations in three assays, we showed that this extract induced p38-α MAPK phosphorylation and the same extract and the p-coumaric acid decreased COX-2 and caspase-3, -8 expression, as well as reduced the TNF-α release and stimulated the IL-10 in RAW 264.7 cells. In L929 cells, the extract and p-coumaric acid induced TGF-ß release, besides increasing the process of cell migration and proliferation. These results suggested that the healing properties of Myrciaria plinioides aqueous extract can be associated to the presence of phenolic compounds, especially p-coumaric acid, and/or glycosylated metabolites.

Combinatorial effects of hydroxyapatite and Tualang honey on medication-related osteonecrosis of the jaw (MRONJ): An in vitro study.

BACKGROUND: Medication-related osteonecrosis of the jaw (MRONJ) is a severe complication associated with prolonged bisphosphonate therapy. Increasing evidence shows that mucosal damage plays an important role in the pathogenesis of MRONJ. This study investigates the combinatorial effects of hydroxyapatite with Tualang honey on cell viability and wound healing in MRONJ. MATERIALS AND METHODS: The incorporation of Tualang honey into hydroxyapatite was assessed using Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD) and field emission scanning electron-energy dispersive X-ray analysis microscopy (FESEM-EDX). The effect of hydroxyapatite combined with Tualang honey on cell viability was determined by WST-1 assay and wound healing was assessed by scratch assay. RESULTS: The incorporation of Tualang honey into hydroxyapatite altered the functional groups, structure, size, morphology, and components of the crystal as evidenced by FTIR, XRD and FESEM-EDX analysis. High concentrations of pamidronic acid inhibit oral fibroblast viability and wound healing. Low and high concentrations of hydroxyapatite demonstrate non-toxicity towards fibroblast cells. Furthermore, hydroxyapatite reversed the action of pamidronic acid on the cells; it increased fibroblast viability but did not close the wound. Tualang honey promotes fibroblast viability and wound closure. However, the addition of Tualang honey is unable to overcome the inhibitory effects of pamidronic acid on fibroblasts. The addition of Tualang honey and hydroxyapatite improved the cell viability and accelerated wound closure of fibroblast exposed to pamidronic acid. CONCLUSION: These findings demonstrated that the combination treatment protects oral fibroblasts by preventing bisphosphonate toxicity.

[Corrigendum] Cancer­associated fibroblasts from invasive breast cancer have an attenuated capacity to secrete collagens.

Subsequently to the publication of the above article, an interested reader drew to the authors' attention that the GAPDH bands shown for the western blots portrayed in Fig. 2 (associated with the α­SMA proteins) on p. 1482 were strikingly similar to the GAPDH bands associated with the CAF64 and NF64 experiments in Fig. 4 on p. 1485. After re­examining their original data, the authors have realized that the GAPDH protein bands correctly shown in Fig. 4 had inadvertently been included in Fig. 2. The revised version of Fig. 2, showing the GAPDH bands that were correctly associated with the α­SMA proteins, is shown opposite. The authors are grateful to the Editor of International Journal of Oncology for allowing them this opportunity to publish a Corrigendum, and all the authors agree to its publication. Note that this error did not grossly affect either the results or the conclusions reported in this study; furthermore, the authors apologize to the readership for any inconvenience caused. [International Journal of Oncology 45: 1479­1488, 2014; DOI: 10.3892/ijo.2014.2562].

Unlocking the potential: Targeting metabolic pathways in the tumor microenvironment for Cancer therapy.

Cancer incidence and mortality are increasing and impacting global life expectancy. Metabolic reprogramming in the tumor microenvironment (TME) is intimately related to tumorigenesis, progression, metastasis and drug resistance. Tumor cells drive metabolic reprogramming of other cells in the TME through metabolic induction of cytokines and metabolites, and metabolic substrate competition. Consequently, this boosts tumor cell growth by providing metabolic support and facilitating immunosuppression and angiogenesis. The metabolic interplay in the TME presents potential therapeutic targets. Here, we focus on the metabolic reprogramming of four principal cell subsets in the TME: CAFs, TAMs, TILs and TECs, and their interaction with tumor cells. We also summarize medications and therapies targeting these cells' metabolic pathways, particularly in the context of immune checkpoint blockade therapy.

Synovial microenvironment in temporomandibular joint osteoarthritis: crosstalk with chondrocytes and potential therapeutic targets.

Temporomandibular joint osteoarthritis (TMJOA) is considered to be a low-grade inflammatory disease involving multiple joint tissues. The crosstalk between synovium and cartilage plays an important role in TMJOA. Synovial cells are a group of heterogeneous cells and synovial microenvironment is mainly composed of synovial fibroblasts (SF) and synovial macrophages. In TMJOA, SF and synovial macrophages release a large number of inflammatory cytokines and extracellular vesicles and promote cartilage destruction. Cartilage wear particles stimulate SF proliferation and macrophages activation and exacerbate synovitis. In TMJOA, chondrocytes and synovial cells exhibit increased glycolytic activity and lactate secretion, leading to impaired chondrocyte matrix synthesis. Additionally, the synovium contains mesenchymal stem cells, which are the seed cells for cartilage repair in TMJOA. Co-culture of chondrocytes and synovial mesenchymal stem cells enhances the chondrogenic differentiation of stem cells. This review discusses the pathological changes of synovium in TMJOA, the means of crosstalk between synovium and cartilage, and their influence on each other. Based on the crosstalk between synovium and cartilage in TMJOA, we illustrate the treatment strategies for improving synovial microenvironment, including reducing cell adhesion, utilizing extracellular vesicles to deliver biomolecules, regulating cellular metabolism and targeting inflammatory cytokines.

Consensus clustering and development of a risk signature based on trajectory differential genes of cancer-associated fibroblast subpopulations in colorectal cancer.

BACKGROUND: Cancer-associated fibroblasts (CAFs) play a crucial role in the progression of colorectal cancer (CRC). However, the impact of CAF subpopulation trajectory differentiation on CRC remains unclear. METHODS: In this study, we first explored the trajectory differences of CAFs subpopulations using bulk and integrated single-cell sequencing data, and then performed consensus clustering of CRC samples based on the trajectory differential genes of CAFs subpopulations. Subsequently, we analyzed the heterogeneity of CRC subtypes using bioinformatics. Finally, we constructed relevant prognostic signature using machine learning and validated them using spatial transcriptomic data. RESULTS: Based on the differential genes of CAFs subpopulation trajectory differentiation, we identified two CRC subtypes (C1 and C2) in this study. Compared to C1, C2 exhibited worse prognosis, higher immune evasion microenvironment and high CAF characteristics. C1 was primarily associated with metabolism, while C2 was primarily associated with cell metastasis and immune regulation. By combining 101 combinations of 10 machine learning algorithms, we developed a High-CAF risk signatures (HCAFRS) based on the C2 characteristic gene. HCAFRS was an independent prognostic factor for CRC and, when combined with clinical parameters, significantly predicted the overall survival of CRC patients. HCAFRS was closely associated with epithelial-mesenchymal transition, angiogenesis, and hypoxia. Furthermore, the risk score of HCAFRS was mainly derived from CAFs and was validated in the spatial transcriptomic data. CONCLUSION: In conclusion, HCAFRS has the potential to serve as a promising prognostic indicator for CRC, improving the quality of life for CRC patients.

Exploring the molecular mechanisms and shared potential drugs between rheumatoid arthritis and arthrofibrosis based on large language model and synovial microenvironment analysis.

Rheumatoid arthritis (RA) and arthrofibrosis (AF) are both chronic synovial hyperplasia diseases that result in joint stiffness and contractures. They shared similar symptoms and many common features in pathogenesis. Our study aims to perform a comprehensive analysis between RA and AF and identify novel drugs for clinical use. Based on the text mining approaches, we performed a correlation analysis of 12 common joint diseases including arthrofibrosis, gouty arthritis, infectious arthritis, juvenile idiopathic arthritis, osteoarthritis, post infectious arthropathies, post traumatic osteoarthritis, psoriatic arthritis, reactive arthritis, rheumatoid arthritis, septic arthritis, and transient arthritis. 5 bulk sequencing datasets and 4 single-cell sequencing datasets of RA and AF were integrated and analyzed. A novel drug repositioning method was found for drug screening, and text mining approaches were used to verify the identified drugs. RA and AF performed the highest gene similarity (0.77) and functional ontology similarity (0.84) among all 12 joint diseases. We figured out that they share the same key pathogenic cell including CD34 + sublining fibroblasts (CD34-SLF) and DKK3 + sublining fibroblasts (DKK3-SLF). Potential therapeutic target database (PTTD) was established with the differential expressed genes (DEGs) of these key pathogenic cells. Based on the PTTD, 15 potential drugs for AF and 16 potential drugs for RA were identified. This work provides a new perspective on AF and RA study which enhances our understanding of their pathogenesis. It also shed light on their underlying mechanism and open new avenues for drug repositioning studies.

Cancer-associated fibroblasts derived exosomal LINC01833 promotes the occurrence of non-small cell lung cancer through miR-335-5p -VAPA axis.

Cancer-associated fibroblasts (CAFs) are an important component of the tumor microenvironment (TME) and can induce functional polarization of tumor macrophages. This study aimed to explore the effect of CAFs-derived exosome LINC01833 on the malignant biological behavior of non-small cell lung cancer (NSCLC) cells and its mechanism. Tumor tissues (n = 3) and adjacent noncancerous tissues (n = 3) were collected from patients with NSCLC, and fibroblasts (CAF, NF) were isolated from the two tissues. Expression of LINC01833/miR-335-5p/VAPA in NSCLC clinical tissues and cell lines was detected by RT-qPCR. Exosomes of CAFs and NFs were isolated by ultracentrifugation. Cell proliferation, migration, invasion, and M2 macrophage polarization were detected by MTT, transwell, wound-healing assay, and flow cytometry assay, while western blot was used to verify the expression of M2 macrophage polarization-related proteins. Tumor volume weight and M2 macrophage polarization were detected by tumor xenografts in nude mice. LINC01833 was highly expressed in NSCLC tumor tissues and cells. Knockdown of LINC01833 exosomes could significantly inhibit proliferation, migration, invasion of NSCLC cells, and M2 macrophage polarization of THP-1 cells, while simultaneous knockdown of miR-335-5p on the above basis could reverse the effect of knockdown of LINC01833. In vivo experiments also indicated that knockdown of LINC01833 exosomes suppressed tumor growth and M2 macrophage polarization. CAF-derived LINC01833 exosomes can promote the proliferation, migration and invasion of NSCLC cells and M2 macrophage polarization by inhibiting miR-335-5p and regulating VAPA activity.

The role of cancer-associated fibroblasts in the invasion and metastasis of colorectal cancer.

Colorectal cancer (CRC) is the third most common cancer and has ranked the third leading cause in cancerassociated death globally. Metastasis is the leading cause of death in colorectal cancer patients. The role of tumor microenvironment (TME) in colorectal cancer metastasis has received increasing attention. As the most abundant cell type in the TME of solid tumors, cancer-associated fibroblasts (CAFs) have been demonstrated to have multiple functions in advancing tumor growth and metastasis. They can remodel the extracellular matrix (ECM) architecture, promote epithelial-mesenchymal transition (EMT), and interact with cancer cells or other stromal cells by secreting growth factors, cytokines, chemokines, and exosomes, facilitating tumor cell invasion into TME and contributing to distant metastasis. This article aims to analyze the sources and heterogeneity of CAFs in CRC, as well as their role in invasion and metastasis, in order to provide new insights into the metastasis mechanism of CRC and its clinical applications.

Sinoatrial node heterogeneity and fibroblasts increase atrial driving capability in a two-dimensional human computational model.

Background: Cardiac pacemaking remains an unsolved matter from many perspectives. Extensive experimental and computational studies have been performed to describe the sinoatrial physiology across different scales, from the molecular to clinical levels. Nevertheless, the mechanism by which a heartbeat is generated inside the sinoatrial node and propagated to the working myocardium is not fully understood at present. This work aims to provide quantitative information about this fascinating phenomenon, especially regarding the contributions of cellular heterogeneity and fibroblasts to sinoatrial node automaticity and atrial driving. Methods: We developed a bidimensional computational model of the human right atrial tissue, including the sinoatrial node. State-of-the-art knowledge of the anatomical and physiological aspects was adopted during the design of the baseline tissue model. The novelty of this study is the consideration of cellular heterogeneity and fibroblasts inside the sinoatrial node for investigating the manner by which they tune the robustness of stimulus formation and conduction under different conditions (baseline, ionic current blocks, autonomic modulation, and external high-frequency pacing). Results: The simulations show that both heterogeneity and fibroblasts significantly increase the safety factor for conduction by more than 10% in almost all the conditions tested and shorten the sinus node recovery time after overdrive suppression by up to 60%. In the human model, especially under challenging conditions, the fibroblasts help the heterogeneous myocytes to synchronise their rate (e.g. -82% in σ C L under 25 nM of acetylcholine administration) and capture the atrium (with 25% L-type calcium current block). However, the anatomical and gap junctional coupling aspects remain the most important model parameters that allow effective atrial excitations. Conclusion: Despite the limitations to the proposed model, this work suggests a quantitative explanation to the astonishing overall heterogeneity shown by the sinoatrial node.

Identification of miRNA signature in cancer-associated fibroblast to predict recurrent prostate cancer.

BACKGROUND: Cancer-associated fibroblasts (CAFs) are one of the major components of prostate stromal cells, which play a crucial part in tumor development and treatment resistance. This study aimed to establish a model of CAFs-related microRNAs (miRNAs) to assess prognostic differences, tumor microenvironments, and screening of anticancer drugs by integrating data from single-cell RNA sequencing (scRNA-seq) and bulk RNA sequencing (buRNA-seq). METHODS: scRNA-seq and buRNA-seq data of primary prostate cancer (PCa) were downloaded from Gene Expression Omnibus and The Cancer Genome Atlas databases. Statistical methods including Least absolute shrinkage and selection operator (Lasso), Lasso penalized, Random Forest, Random Forest Combination, and Support Vector Machine (SVM) were performed to select hub miRNAs. Pathway analyses and assessment of infiltrating immune cells were conducted using Gene Set Enrichment Analysis and the CIBERSORT algorithm. The expression of CAFs-related miRNAs in fibroblast cell lines were validated through quantitative real-time PCR. Cell Counting Kit 8 (CCK8), wound-healing, clone formation, and cell migration assays were used to explore cell proliferation, growth, and migration in vitro. A mouse xenograft model was established to investigate the effect of CAFs on tumor growth in vivo. RESULTS: Through single-cell transcriptomics analysis in 34 PCa patients, 89 CAFs-related mRNAs were identified. A prognostic model based on 9 CAFs-related miRNAs (hsa-miR-1258, hsa-miR-133b, hsa-miR-222-3p, hsa-miR-145-3p, hsa-miR-493-5p, hsa-miR-96-5p, hsa-miR-15b-5p, hsa-miR-106b-5p, and hsa-miR-191-5p) was established to predict biochemical recurrence (BCR). We have determined through two prediction methods that NVP-TAE684 may be the optimal targeted therapy drug for treating CAFs. Downregulation of hsa-miR-106b-5p in CAFs significantly suppressed cell proliferation, migration, and colony formation in vitro. In vivo studies using a xenograft model further confirmed that hsa-miR-106b-5p downregulation significantly reduced tumor growth. CONCLUSION: Our findings conducted an integrated bioinformatic analysis to develop a CAFs-related miRNAs model that provides prognostic insights into individualized and precise treatment for prostate adenocarcinoma patients. Downregulation of miR-106b-5p in CAFs significantly suppressed tumor growth, suggesting a potential therapeutic target for cancer treatment.

Detection of Carcinoma-Associated Fibroblasts Derived from Mesothelial Cells via Mesothelial-to-Mesenchymal Transition in Primary Ovarian Carcinomas.

Carcinoma-associated fibroblasts (CAFs) are highly accumulated in the tumor-surrounding stroma of primary epithelial ovarian cancer (OC). CAFs exert important functions for the vascularization, growth, and progression of OC cells. However, the origin of CAFs in primary OC had not yet been studied, and they were assumed to arise from the activation of resident fibroblasts. Here, we compared CAFs in the ovary to CAFs found in peritoneal metastases from patients with advanced OC. Our findings show that CAFs from primary tumors and peritoneal metastases share the expression of mesothelial markers. Therefore, similar to peritoneal carcinomatosis, CAFs in primary ovarian carcinomas may originate from mesothelial cells via a mesothelial-to-mesenchymal transition. The detection of mesothelial-derived CAFs in tumors confined to the ovary and identification of biomarkers could be the key to the early detection of OC and peritoneal spread.