Cancer-associated Fibroblasts Infiltration Research Articles

Pathomics and single-cell analysis of papillary thyroid carcinoma reveal the pro-metastatic influence of cancer-associated fibroblasts

BackgroundPapillary thyroid carcinoma (PTC) is globally prevalent and associated with an increased risk of lymph node metastasis (LNM). The role of cancer-associated fibroblasts (CAFs) in PTC remains unclear.MethodsWe collected postoperative pathological hematoxylin–eosin (HE) slides from 984 included patients with PTC to analyze the density of CAF infiltration at the invasive front of the tumor using QuPath software. The relationship between CAF density and LNM was assessed. Single-cell RNA sequencing (scRNA-seq) data from GSE193581 and GSE184362 datasets were integrated to analyze CAF infiltration in PTC. A comprehensive suite of in vitro experiments, encompassing EdU labeling, wound scratch assays, Transwell assays, and flow cytometry, were conducted to elucidate the regulatory role of CD36+CAF in two PTC cell lines, TPC1 and K1.ResultsA significant correlation was observed between high fibrosis density at the invasive front of the tumor and LNM. Analysis of scRNA-seq data revealed metastasis-associated myoCAFs with robust intercellular interactions. A diagnostic model based on metastasis-associated myoCAF genes was established and refined through deep learning methods. CD36 positive expression in CAFs can significantly promote the proliferation, migration, and invasion abilities of PTC cells, while inhibiting the apoptosis of PTC cells.ConclusionThis study addresses the significant issue of LNM risk in PTC. Analysis of postoperative HE pathological slides from a substantial patient cohort reveals a notable association between high fibrosis density at the invasive front of the tumor and LNM. Integration of scRNA-seq data comprehensively analyzes CAF infiltration in PTC, identifying metastasis-associated myoCAFs with strong intercellular interactions. In vitro experimental results indicate that CD36 positive expression in CAFs plays a promoting role in the progression of PTC. Overall, these findings provide crucial insights into the function of CAF subset in PTC metastasis.

CPT1C-positive cancer-associated fibroblast facilitates immunosuppression through promoting IL-6-induced M2-like phenotype of macrophage

ABSTRACT Cancer-associated fibroblasts (CAFs) exhibit remarkable phenotypic heterogeneity, with specific subsets implicated in immunosuppression in various malignancies. However, whether and how they attenuate anti-tumor immunity in gastric cancer (GC) remains elusive. CPT1C, a unique isoform of carnitine palmitoyltransferase pivotal in regulating fatty acid oxidation, is briefly indicated as a protumoral metabolic mediator in the tumor microenvironment (TME) of GC. In the present study, we initially identified specific subsets of fibroblasts exclusively overexpressing CPT1C, hereby termed them as CPT1C+CAFs. Subsequent findings indicated that CPT1C+CAFs fostered a stroma-enriched and immunosuppressive TME as they correlated with extracellular matrix-related molecular features and enrichment of both immunosuppressive subsets, especially M2-like macrophages, and multiple immune-related pathways. Next, we identified that CPT1C+CAFs promoted the M2-like phenotype of macrophage in vitro. Bioinformatic analyses unveiled the robust IL-6 signaling between CPT1C+CAFs and M2-like phenotype of macrophage and identified CPT1C+CAFs as the primary source of IL-6. Meanwhile, suppressing CPT1C expression in CAFs significantly decreased IL-6 secretion in vitro. Lastly, we demonstrated the association of CPT1C+CAFs with therapeutic resistance. Notably, GC patients with high CPT1C+CAFs infiltration responded poorly to immunotherapy in clinical cohort. Collectively, our data not only present the novel identification of CPT1C+CAFs as immunosuppressive subsets in TME of GC, but also reveal the underlying mechanism that CPT1C+CAFs impair tumor immunity by secreting IL-6 to induce the immunosuppressive M2-like phenotype of macrophage in GC.

Integrative analyses of bulk and single-cell transcriptomics reveals the infiltration and crosstalk of cancer-associated fibroblasts as a novel predictor for prognosis and microenvironment remodeling in intrahepatic cholangiocarcinoma

BackgroundIntrahepatic cholangiocarcinoma (ICC) is a highly malignant neoplasm and characterized by desmoplastic matrix. The heterogeneity and crosstalk of tumor microenvironment remain incompletely understood.MethodsTo address this gap, we performed Weighted Gene Co-expression Network Analysis (WGCNA) to identify and construct a cancer associated fibroblasts (CAFs) infiltration biomarker. We also depicted the intercellular communication network and important receptor-ligand complexes using the single-cell transcriptomics analysis of tumor and Adjacent normal tissue.ResultsThrough the intersection of TCGA DEGs and WGCNA module genes, 784 differential genes related to CAFs infiltration were obtained. After a series of regression analyses, the CAFs score was generated by integrating the expressions of EVA1A, APBA2, LRRTM4, GOLGA8M, BPIFB2, and their corresponding coefficients. In the TCGA-CHOL, GSE89748, and 107,943 cohorts, the high CAFs score group showed unfavorable survival prognosis (p < 0.001, p = 0.0074, p = 0.028, respectively). Additionally, a series of drugs have been predicted to be more sensitive to the high-risk group (p < 0.05). Subsequent to dimension reduction and clustering, thirteen clusters were identified to construct the single-cell atlas. Cell-cell interaction analysis unveiled significant enhancement of signal transduction in tumor tissues, particularly from fibroblasts to malignant cells via diverse pathways. Moreover, SCENIC analysis indicated that HOXA5, WT1, and LHX2 are fibroblast specific motifs.ConclusionsThis study reveals the key role of fibroblasts - oncocytes interaction in the remodeling of the immunosuppressive microenvironment in intrahepatic cholangiocarcinoma. Subsequently, it may trigger cascade activation of downstream signaling pathways such as PI3K-AKT and Notch in tumor, thus initiating tumorigenesis. Targeted drugs aimed at disrupting fibroblasts-tumor cell interaction, along with associated enrichment pathways, show potential in mitigating the immunosuppressive microenvironment that facilitates tumor progression.

Abstract PO5-21-05: An Endocrine Resistant-Related Gene Signature Revealing the Tumor Microenvironment to Predict the Prognosis of Hormone Receptor-Positive Breast Cancer Patients

Abstract Key words: breast cancer; hormone receptor-positive; predictive model; prognosis; endocrine therapy; drug resistance Hormone receptor positive (HR+) breast cancer is the most common type of breast cancer, accounting for approximately 70% of all breast cancer, in whom endocrine therapy plays a vital role. However, the limited effectiveness of endocrine therapy due to intricate mechanisms of drug resistance poses a significant challenge in treating certain patients. Therefore, it is imperative to identify novel indicators of endocrine resistance and develop new models for predicting recurrence-free survival (RFS) in patients with HR+ breast cancer. In this study, we successfully established an endocrine resistance-related risk model based on multicenter RNA sequencing data. This model could represent tumor microenvironment characteristics and provide valuable insights into predicting the prognosis of HR+ breast cancer patients. A seven gene risk model reflecting endocrine therapy resistance in 208 early HR+ breast cancer patients from two centers was constructed by LASSO analysis and multivariate cox regression. Based on the median value of risk score, patients were divided into high-risk group and low-risk group. Compared with the low-risk group, the high-risk group exhibited a significantly worse prognosis, which showed consistent across two external validation cohorts (TCGA-BRCA and METABRIC cohort). Time dependent ROC curve showed excellent capacity of gene model in predicting 1,3 and 5-year RFS. The IC50 analysis revealed that patients in low-risk group exhibited greater sensitivity to endocrine drugs, such as tamoxifen, fulvestrant and palbociclib, which strongly suggested that the identified gene signature can effectively differentiate between endocrine-resistant and -sensitive status. Gene-set enrichment analysis revealed regulation of cell killing, positive regulation of inflammatory response and T cell mediated cytotoxicity were enriched in low risk group, suggesting immune activation and a higher immune infiltration status. Conversely, the high-risk group demonstrated associations with collagen metabolic process, extracellular matrix structural constituent and collagen fibril organization, which were the indicative of the location and function of cancer-associated fibroblasts (CAFs). As expected, ssGSEA results revealed elevated expression levels of immune cells (e.g., natural killer cells, tumor-infiltrating lymphocytes, CD8+ T cells) and immune functions (e.g., T cell co-stimulation, inflammation-promoting, cytolytic activity) in the low-risk group. However, three diverse acknowledged methods (TIDE, EPIC and MCP-counter) consistently identified CAFs as predominantly content in the high-risk groups. Furthermore, considering that CD8+ T cell is the primary cell type responsible for exerting cytotoxic effects, we observed a negative correlation between CD8+ T cells and CAFs. This suggests that CAFs may inhibit the infiltration of CD8+ T cells, thereby weakening their cytotoxic capabilities, leading to a shorter RFS in high-risk patient groups. In conclusion, a novel gene signature constructed with 7 endocrine resistance response-related genes can be used for prognostic prediction and reflecting the tumor microenvironment status in HR+ early breast cancer. The low-risk group exhibited enhanced anti-tumor immunity, resulting in a favorable prognosis. In contrast, the high-risk group displayed pronounced infiltration of CAFs, indicating their potential to impede immune cell infiltration and impact the efficacy of endocrine drugs through the formation of physical barriers and recruitment of immunosuppressive factors. Consequently, patients in the high-risk group experienced a worse prognosis. Therefore, inhibiting these genes may be a therapeutic option for overcoming endocrine therapy resistance in HR+ breast cancer patients. Citation Format: Xiyu Kang, Jiaxiang Liu, Xin Wang. An Endocrine Resistant-Related Gene Signature Revealing the Tumor Microenvironment to Predict the Prognosis of Hormone Receptor-Positive Breast Cancer Patients [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 PO5-21-05.

VDR is a potential prognostic biomarker and positively correlated with immune infiltration: a comprehensive pan-cancer analysis with experimental verification.

The vitamin D receptor (VDR) is a transcription factor that mediates a variety of biological functions of 1,25-dihydroxyvitamin D3. Although there is growing evidence of cytological and animal studies supporting the suppressive role of VDR in cancers, the conclusion is still controversial in human cancers and no systematic pan-cancer analysis of VDR is available. We explored the relationships between VDR expression and prognosis, immune infiltration, tumor microenvironment, or gene set enrichment analysis (GSEA) in 33 types of human cancers based on multiple public databases and R software. Meanwhile, the expression and role of VDR were experimentally validated in papillary thyroid cancer (PTC). VDR expression decreased in 8 types and increased in 12 types of cancer compared with normal tissues. Increased expression of VDR was associated with either good or poor prognosis in 13 cancer types. VDR expression was positively correlated with the infiltration of cancer-associated fibroblasts, macrophages, or neutrophils in 20, 12, and 10 cancer types respectively and this correlation was experimentally validated in PTC. Increased VDR expression was associated with increased percentage of stromal or immune components in tumor microenvironment (TME) in 24 cancer types. VDR positively and negatively correlated genes were enriched in immune cell function and energy metabolism pathways, respectively, in the top 9 highly lethal tumors. Additionally, VDR expression was increased in PTC and inhibited cell proliferation and migration. In conclusion, VDR is a potential prognostic biomarker and positively correlated with immune infiltration as well as stromal or immune components in TME in multiple human cancers.

Integrative analysis of the bladder cancer from a cell cycle NCAM1 perspective at both single cell and bulk resolution.

Bladder cancer (BLCA) is a prevalent and deadly form of urinary cancer, and there is a need for effective therapies, particularly for muscle-invasive bladder cancer (MIBC). Cell cycle inhibitors show promise in restoring control of the cell cycle in BLCA cells, but their clinical prognosis evaluation is limited. Transcriptome and scRNA-seq data were collected from the Cancer Genome Atlas Program (TCGA)-BLCA and GSE190888 cohort, respectively. R software and the Seurat package were used for data analysis, including cell quality control, dimensionality reduction, and identification of differentially expressed genes. Genes related to the cell cycle were obtained from the genecards website, and a protein-protein interaction network analysis was performed using cytoscape software. Functional enrichment analysis, immune infiltration analysis, drug sensitivity analysis, and molecular docking were conducted using various tools and packages. BLCA cell lines were cultured and transfected for in vitro experimental assays, including RT-qPCR analysis, and CCK-8 cell viability assays. We identified 32 genes as independent risk or protective factors for BLCA prediction. Functional enrichment analysis revealed their involvement in cell cycle regulation, apoptosis, and various signaling pathways. Using these genes, we developed a nomogram for predicting BLCA survival, which displayed high prognosis stratification efficacy in BLCA patients. Four cell cycle associated key genes identified, including NCAM1, HBB, CKD6, and CTLA4. We also identified the main cell types in BLCA patients and investigated the functional differences between epithelial cells based on their expression levels of key genes. Furthermore, we observed a high positive correlative relationship between the infiltration of cancer-associated fibroblasts and the risk score value. Finally, we conducted in vitro experiments to demonstrate the suppressive role of NCAM1 in BLCA cell proliferation. These findings suggest that cell cycle associated genes could serve as potential biomarkers for predicting BLCA prognosis and may represent therapeutic targets for the development of more effective therapies. Hopefully, these findings provide valuable insights into the molecular mechanisms and potential therapeutic targets in BLCA from the perspective of cell cycle. Moreover, NCAM1 was a novel cell proliferation suppressor in the BLCA carcinogenesis.

Identification of CREB5 as a prognostic and immunotherapeutic biomarker in glioma through multi-omics pan-cancer analysis

BackgroundThe functional relevance of cyclic adenosine monophosphate (cAMP)-response element-binding protein 5 (CREB5) in cancers remains elusive, despite its significance as a member of the CREB family. The current research aims to explore the role of CREB5 in multiple cancers. MethodsPan-cancer analysis was performed to explore the expression patterns, prognostic value, mutational landscape as well as single-cell omic, immunologic, and drug sensitivity profiles of CREB5. Furthermore, we incorporated five distinct machine learning algorithms and determined that the least absolute shrinkage and selection operator-COX (LASSO-COX) algorithm, which exhibited the highest C index, was the optimal selection. Subsequently, we constructed a prognostic model centered around CREB5-associated genes. To elucidate the biological function of CREB5 in glioma cells, several assays including cell counting kit-8 (CCK-8), wound healing, transwell, flow cytometric were performed. ResultsCREB5 was overexpressed in pan-cancer and was linked to unfavorable prognosis, particularly in glioma. Furthermore, genetic alterations were determined in various types of cancer, and modifications in the CREB5 gene were linked to the prognosis. The single-cell omics and enrichment analyses showed that CREB5 was predominantly expressed in malignant glioma cells and was critically involved in the regulation of various oncogenic processes. Elevated levels of CREB5 were strongly linked with the infiltration of cancer-associated fibroblasts and the Th1 subset of CD4+ T cells. The validated CREB5-associated prognostic model reliably predicted the prognosis and drug response of glioma patients. The in vitro experiments showed that CREB5 promoted glioma cell proliferation, invasion, migration, and gap phase 2/mitotic (G2/M) phase arrest and recruited M2 macrophages into glioma cells. ConclusionCREB5 has the potential to act as an oncogene and a biological marker in multiple cancers, particularly glioma.

Cancer-associated fibroblasts rewire the estrogen receptor response in luminal breast cancer, enabling estrogen independence.

Advanced breast cancers represent a major therapeutic challenge due to their refractoriness to treatment. Cancer-associated fibroblasts (CAFs) are the most abundant constituents of the tumor microenvironment and have been linked to most hallmarks of cancer. However, the influence of CAFs on therapeutic outcome remains largely unchartered. Here, we reveal that spatial coincidence of abundant CAF infiltration with malignant cells was associated with reduced estrogen receptor (ER)-α expression and activity in luminal breast tumors. Notably, CAFs mediated estrogen-independent tumor growth by selectively regulating ER-α signaling. Whereas most prototypical estrogen-responsive genes were suppressed, CAFs maintained gene expression related to therapeutic resistance, basal-like differentiation, and invasion. A functional drug screen in co-cultures identified effector pathways involved in the CAF-induced regulation of ER-α signaling. Among these, the Transforming Growth Factor-β and the Janus kinase signaling cascades were validated as actionable targets to counteract the CAF-induced modulation of ER-α activity. Finally, genes that were downregulated in cancer cells by CAFs were predictive of poor response to endocrine treatment. In conclusion, our work reveals that CAFs directly control the luminal breast cancer phenotype by selectively modulating ER-α expression and transcriptional function, and further proposes novel targets to disrupt the crosstalk between CAFs and tumor cells to reinstate treatment response to endocrine therapy in patients.

CRABP2 regulates infiltration of cancer-associated fibroblasts and immune response in melanoma.

Finding biomarkers for immunotherapy is an urgent issue in cancer treatment. Cellular retinoic acid-binding protein 2 (CRABP2) is a controversial factor in the occurrence and development of human tumors. However, there is limited research on the relationship between CRABP2 and immunotherapy response. This study found that negative correlations of CRABP2 and immune checkpoint markers (PD-1, PD-L1, and CTLA-4) were observed in breast invasive carcinoma (BRCA), skin cutaneous melanoma (SKCM), stomach adenocarcinoma (STAD) and testicular germ cell tumors (TGCT). In particular, in SKCM patients who were treated with PD-1 inhibitors, high levels of CRABP2 predicted poor prognosis. Additionally, CRABP2 expression was elevated in cancer-associated fibroblasts (CAFs) at the single-cell level. The expression of CRABP2 was positively correlated with markers of CAFs, such as MFAP5, PDPN, ITGA11, PDGFRα/β and THY1 in SKCM. To validate the tumor-promoting effect of CRABP2 in vivo, SKCM xenograft mice models with CRABP2 overexpression have been constructed. These models showed an increase in tumor weight and volume. Enrichment analysis indicated that CRABP2 may be involved in immune-related pathways of SKCM, such as extracellular matrix (ECM) receptor interaction and epithelial-mesenchymal transition (EMT). The study suggests that CRABP2 may regulate immunotherapy in SKCM patients by influencing infiltration of CAFs. In conclusion, this study provides new insights into the role of CRABP2 in immunotherapy response. The findings suggest that CRABP2 may be a promising biomarker for PD-1 inhibitors in SKCM patients. Further research is needed to confirm these findings and to explore the clinical implications of CRABP2 in immunotherapy.

A pan-cancer analysis of the role of argininosuccinate synthase 1 in human tumors.

There is accumulating evidence indicating that ASS1 is closely related to tumors. No pan-cancer analysis of ASS1 was available. Here we explored the gene expression and survival analysis of ASS1 across thirty-three tumors based on the datasets of the TCGA (Cancer Genome Atlas), the GEO (Gene Expression Omnibus), and the GEPIA2 (Gene Expression Profiling Interactive Analysis, version 2). ASS1 is highly expressed in most normal tissues and is related to the progression of some tumors. We also report ASS1 genetic alteration and their association with tumor prognosis and report differences in ASS1 phosphorylation sites between tumors and control normal tissues. ASS1 expression was associated with the infiltration of cancer-associated fibroblasts (CAFs) for the TCGA tumors of BRCA (Breast invasive carcinoma), CESC (Cervical squamous cell carcinoma and endocervical adenocarcinoma), COAD (Colon adenocarcinoma), ESCA (Esophageal carcinoma), SKCM (Skin cutaneous melanoma), SKCM-Metastasis, TGCT (Testicular germ cell tumors), and endothelial cell for the tumors of BRCA, BRCA-Basal, CESC, ESCA, KIRC (Kidney renal clear cell carcinoma), LUAD (Lung adenocarcinoma), LUSC (Lung squamous cell carcinoma), SKCM, SKCM-Metastasis, SKCM-Primary, STAD (Stomach adenocarcinoma), and TGCT. The KEGG and GO analysis were used to analyze ASS1-related signaling pathways. Finally, we used Huh7 cell line to verify the function of ASS1 in vitro. After ASS1 knockdown using small interfering RNA (siRNA), the proliferation and invasion of Huh7 were enhanced, cyclin D1 was up-regulated, and anti-apoptotic protein bax was down-regulated, suggesting that ASS1 is a tumor suppressor gene in hepatocellular carcinoma. Our first pan-cancer study offers a relatively comprehensive understanding of the roles of ASS1 in different tumors.

Multi-omics analysis of the oncogenic role of optic atrophy 1 in human cancer.

To investigate the prognostic significance of optic atrophy 1 (OPA1) in pan-cancer and analyze the relationship between OPA1 and immune infiltration in cancer. OPA1 exhibited high expression levels or mutations in various types of tumor cells, and its expression levels were significantly correlated with the survival rate of tumor patients. In different tumor tissues, there was a notable positive correlation between OPA1 expression levels and the infiltration of cancer-associated fibroblasts in the immune microenvironment. Additionally, OPA1 and its related genes were found to be involved in several crucial biological processes, including protein phosphorylation, protein import into the nucleus, and protein binding. OPA1 is highly expressed or mutated in numerous tumors and is strongly associated with protein phosphorylation, patient prognosis, and immune cell infiltration. OPA1 holds promise as a novel prognostic marker with potential clinical utility across various tumor types. We examined OPA1 expression in pan-cancer at both the gene and protein levels using various databases, including Tumor Immune Estimation Resource 2.0 (TIMER 2.0), Gene Expression Profiling Interactive Analysis (GEPIA2), UALCAN, and The Human Protein Atlas (HPA). We utilized the Kaplan-Meier plotter and GEPIA datasets to analyze the relationship between OPA1 expression levels and patient prognosis. Through the cBioPortal database, we detected OPA1 mutations in tumors and examined their relationship with patient prognosis. We employed the TIMER 2.0 database to explore the correlation between OPA1 expression levels in tumor tissue and the infiltration of cancer-associated fibroblasts in the immune microenvironment. Furthermore, we conducted a gene search associated with OPA1 and performed enrichment analysis to identify the main signaling pathways and biological processes linked to them.

An integrated analysis identifies six molecular subtypes of pancreatic ductal adenocarcinoma revealing cellular and molecular landscape.

Pancreatic ductal adenocarcinoma (PDA) has been found to have a high mortality rate. Despite continuous efforts, current histopathological classification is insufficient to guide individualized therapies of PDA. We first define the molecular subtypes of PDA (MSOP) based on a meta-cohort of 845 samples from 11 PDA datasets. We then performed functional analyses involving immunity, fibrosis and metabolism. We recognized six molecular subtypes with different survival statistics and molecular composition. The squamous basal-like (SBL) subtype had a poor prognosis and high infiltration of ENO1+ (Enolase 1)/ADM+ (Adrenomedullin) cancer-associated fibroblasts (CAFs). The immune mesenchymal-like (IML) subtype and the normal mesenchymal-like (NML) subtype were characterized by genes associated with extracellular matrix (ECM) activities and immune responses, having favorable prognoses. IML was featured by elevated exhausted immune signaling and inflammatory CAFs infiltration, whereas NML was featured with myofibroblastic CAFs infiltration. The exocrine-like (EL) subtype was high in exocrine signals, while the pure classical-like (PCL) subtype lacked immunocytes infiltration. The quiescent-like (QL) subtype had diminished metabolic signaling and high infiltration of NK cells. SBL, IML and NML were enriched in innate anti-PD-1 resistance signatures. In sum, this MSOP depicts a vivid cell-to-molecular atlas of the tumor microenvironment of PDA and might facilitate to design a precise combination of therapies that target immunity, metabolism and stroma.

Microdissection of cancer-associated fibroblast infiltration subtypes unveils the secreted SERPINE2 contributing to immunosuppressive microenvironment and immuotherapeutic resistance in gastric cancer: A large-scale study integrating bulk and single-cell transcriptome profiling

In the era of immunotherapy, the suboptimal response rate and the development of acquired resistance among the initial beneficiaries continue to present significant challenges across multiple malignancies, including gastric cancer (GC). Considering that the interactions of tumor stroma, especially the cancer-associated fibroblasts (CAFs), with immune and tumor cells, play indispensable roles in tumor progression, tumor microenvironment remodeling and therapeutic responsiveness, in-depth exploration on the roles of CAFs and pivotal mediators of their functions may provide novel clues to increase the effectiveness of current immunotherapeutic drugs and further achieve synergistic antitumor response. Herein, through the consensus clustering of canonical biomarkers, three GC subclasses with different abundance of CAFs were virtually microdissected in four integrated bulk cohorts encompassing 2148 GC patients from 11 independent datasets. An extensive immunogenomic analysis revealed that tumors with high CAFs infiltration were characterized with unfavorable outcomes, aggressive phenotypes, decreased tumor immunogenicity, high risk of immune evasion and thus immunotherapeutic resistance. By leveraging large-scale single-cell transcriptomic profiling, a series of CAF-secreted proteins were identified, among which the SERPINE2 was confirmed to be restrictively enriched in stromal fibroblasts of GC tissues and contribute to promoting a protumor milieu and fostering an immunosuppressive microenvironment via bioinformatics computations and tissue microarray analysis. Moreover, pan-cancer investigations generalized the immunological roles of SERPINE2, especially in pan-gastrointestinal malignancies, with multiple real-world immunotherapy cohorts further confirming its implications on predicting immunotherapeutic efficacy. In conclusion, these findings suggest that the CAF-derived SERPINE2 is a promising immune-oncology target with therapeutic implications to further synergize the immunotherapeutic combinations.

A gene signature of cancer-associated fibroblasts predicts prognosis and treatment response in bladder cancer.

Due to the pivotal role cancer-associated fibroblasts (CAFs) play in tumor progression, our study aimed to develop a signature of CAFs-related gene (CRG) to predict the survival outcomes and treatment response of bladder cancer (BLCA). The transcriptome data and relevant clinical information about BLCA were collected from publicly available databases, including The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) datasets. Weighted gene co-expression network analysis was utilized to uncover CAFs-associated hub genes, and subsequently, a risk model for survival prognosis was constructed using LASSO-Cox regression. The immune microenvironment, immune infiltration, immunotherapy response, and drug sensitivity were explored using ESTIMATE, CIBERSORT, TIDE, and oncoPredict algorithms. To verify the expression of the CRGs, additional analyses were performed using online databases (HPA, CCLE, TIMER, cBioPortal, and TISCH). Our study developed a CRG signature and constructed a prognostic model. Significant differences in overall survival were observed between the two risk stratifications. The risk score increased with the infiltration of CAFs and tumor staging progression, while closely correlating with immune checkpoint expression and infiltration of CD8 T cells, follicular helper T cells, regulatory T cells, activated dendritic cells, M0 macrophages, M2 macrophages, and resting mast cells. Furthermore, a higher proportion of patients in the low-risk stratification exhibited responsiveness to immunotherapy, and significant variances in sensitivity to multiple chemotherapy medications were observed between the two risk stratifications. The construction of the risk model based on the CRG signature offers new avenues for the prognosis evaluation and development of personalized treatment strategies for BLCA.

Immunosuppressive MFAP2+ cancer associated fibroblasts conferred unfavorable prognosis and therapeutic resistance in gastric cancer.

To explore the predictive merit of MFAP2+ cancer associated fibroblasts (CAFs) infiltration for clinical outcomes and adjuvant chemotherapy or immunotherapy responsiveness in gastric cancer (GC). In this study, several independent cohorts were included respectively to dissect the relationship of clinical outcomes, therapeutic responses and tumor microenvironment with different MFAP2+ CAFs infiltration. Drug sensitivity analysis was conducted to predict the relationship between MFAP2+ CAFs infiltration and targeted drug response. Kaplan-Meier curves and the log-rank test were used to compare clinical outcomes of patients with different MFAP2+ CAFs infiltration. High MFAP2+ CAFs infiltration yielded inferior prognosis in terms of overall survival, progress free survival and recurrence free survival in GC. Patients with low MFAP2+ CAFs infiltration were more likely to gain benefit from adjuvant therapy. Moreover, low MFAP2+ CAFs infiltration could predict a promising response to immunotherapy in GC patients. MFAP2+ CAFs with immunosuppressive features were highly relevant to immune evasive contexture characterized by the dysfunction of CD8+ T cells. We found that MFAP2+ CAFs communicated with T cells, B cells and Macrophages through releasing macrophage migration inhibitor factor (MIF), which further suggested that MFAP2+ CAFs might promote therapeutic resistance through regulating T cells dysfunction and M2 macrophages polarization. Immunosuppressive MFAP2+ CAFs constructed an immune evasive tumor microenvironment characterized by incapacitated immune effector cells, consequently predicting inferior clinical outcomes and response on adjuvant therapy and immunotherapy in patients with GC. The potential of immunosuppressive MFAP2+ CAFs as a therapeutic target for GC deserved thoroughly exploration.

Identifying a baicalein-related prognostic signature contributes to prognosis prediction and tumor microenvironment of pancreatic cancer.

Pancreatic ductal adenocarcinoma (PDAC) is one of the most malignant and lethal human cancers in the world due to its high metastatic potential, and patients with PDAC have a poor prognosis, yet quite little is understood regarding the underlying biological mechanisms of its high metastatic capacity. Baicalein has a dramatic anti-tumor function in the treatment of different types of cancer. However, the therapeutic effects of baicalein on human PDAC and its mechanisms of action have not been extensively understood. In order to explore the biological characteristic, molecular mechanisms, and potential clinical value of baicalein in inhibiting the metastatic capacity of PDAC. We performed several in vitro, in vivo, and in silico studies. We first examined the potential regulation of baicalein in the metastatic capacity of PDAC cells. We showed that baicalein could dramatically suppress liver metastasis of PDAC cells with highly metastatic potential in mice model. The high-throughput sequencing analysis was employed to explore the biological roles of baicalein in PDAC cells. We found that baicalein might be involved in the infiltration of Cancer-Associated Fibroblasts (CAF) in PDAC. Moreover, a baicalein-related risk model and a lncRNA-related model were built by Cox analysis according to the data set of PDAC from TCGA database which suggested a clinical value of baicalein. Finally, we revealed a potential downstream target of baicalein in PDAC, we proposed that baicalein might contribute to the infiltration of CAF via FGFBP1. Thus, we uncovered a novel role for baicalein in regulation of PDAC liver metastasis that may contribute to its anti-cancer effect. We proposed that baicalein might suppress PDAC liver metastasis via regulation of FGFBP1-mediated CAF infiltration. Our results provide a new perspective on clinical utility of baicalein and open new avenues for the inhibition of liver-metastasis of PDAC.

An HGF-dependent positive feedback loop between bladder cancer cells and fibroblasts mediates lymphangiogenesis and lymphatic metastasis.

Cancer-associated fibroblasts (CAFs) play a vital role in facilitating tumor progression through extensive reciprocal interplay with cancer cells. Tumor-derived extracellular vesicles (EVs) are the critical mediators involved in the crosstalk between cancer cells and stromal cells, contributing to the metastasis of cancers. Yet, the biological mechanisms of tumor-derived EVs in triggering CAFs phenotype to stimulate the lymph node (LN) metastasis of bladder cancer (BCa) are largely unknown. Here, we aimed to explore the effects and molecular mechanisms of tumor-derived EV-mediated CAFs phenotype in regulating BCa LN metastasis. The high-throughput sequencing was utilized to identify the crucial long non-coding RNA (lncRNA) associated with CAF enrichment in BCa. The functional role of the transition of fibroblasts to CAFs induced by LINC00665-mediated EVs was investigated through the in vitro and in vivo assays. Chromatin isolation by RNA purification assays, fluorescence resonance energy transfer assays, cytokine profiling and patient-derived xenograft (PDX) model were performed to explore the underlying mechanism of LINC00665 in the LN metastasis of BCa. We found that CAFs are widely enriched in the tumor microenvironment of BCa, which correlated with BCa lymphangiogenesis and LN metastasis. We then identified a CAF-associated long non-coding RNA, LINC00665, which acted as a crucial mediator of CAF infiltration in BCa. Clinically, LINC00665 was associated with LN metastasis and poor prognosis in patients with BCa. Mechanistically, LINC00665 transcriptionally upregulated RAB27B expression and induced H3K4me3 modification on the promoter of RAB27B through the recruitment of hnRNPL. Moreover, RAB27B-induced EVs secretion endowed fibroblasts with the CAF phenotype, which reciprocally induced LINC00665 overexpression to form a RAB27B-HGF-c-Myc positive feedback loop, enhancing the lymphangiogenesis and LN metastasis of BCa. Importantly, we demonstrated that blocking EV-transmitted LINC00665 or HGF broke this loop and impaired BCa lymphangiogenesis in a PDX model. Our study uncovers a precise mechanism that LINC00665 sustains BCa LN metastasis by inducing a RAB27B-HGF-c-Myc positive feedback loop between BCa cells and fibroblasts, suggesting that LINC00665 could be a promising therapeutic target for patients with LN metastatic BCa.

Hepatocellular carcinoma cells remodel the pro-metastatic tumour microenvironment through recruitment and activation of fibroblasts via paracrine Egfl7 signaling

BackgroundThe tumour microenvironment consists of a complex and dynamic milieu of cancer cells, including tumour-associated stromal cells (leukocytes, fibroblasts, vascular cells, etc.) and their extracellular products. During invasion and metastasis, cancer cells actively remodel the tumour microenvironment and alterations of microenvironment, particularly cancer-associated fibroblasts (CAFs), can promote tumour progression. However, the underlying mechanisms of the CAF formation and their metastasis-promoting functions remain unclear.MethodsPrimary liver fibroblasts and CAFs were isolated and characterized. CAFs in clinical samples were identified by immunohistochemical staining and the clinical significance of CAFs was also analysed in two independent cohorts. A transwell coculture system was used to confirm the role of HCC cells in CAF recruitment and activation. qRT-PCR, western blotting and ELISA were used to screen paracrine cytokines. The role and mechanism of Egfl7 in CAFs were explored via an in vitro coculture system and an in vivo mouse orthotopic transplantation model.ResultsWe showed that CAFs in hepatocellular carcinoma (HCC) are characterized by the expression of α-SMA and that HCC cells can recruit liver fibroblasts (LFs) and activate them to promote their transformation into CAFs. High α-SMA expression, indicating high CAF infiltration, was correlated with malignant characteristics. It was also an independent risk factor for HCC survival and could predict a poor prognosis in HCC patients. Then, we demonstrated that EGF-like domain multiple 7 (Egfl7) was preferentially secreted by HCC cells, and exhibited high potential to recruit and activate LFs into the CAF phenotype. The ability of Egfl7 to modulate LFs relies upon increased phosphorylation of FAK and AKT via the receptor ανβ3 integrin. Strikingly, CAFs activated by paracrine Egfl7 could further remodel the tumour microenvironment by depositing fibrils and collagen and in turn facilitate HCC cell proliferation, invasion and metastasis.ConclusionOur data highlighted a novel role of Egfl7 in remodelling the tumour microenvironment: it recruits LFs and activates them to promote their transformation into CAFs via the ανβ3 integrin signaling pathway, which further promotes HCC progression and contributes to poor clinical outcomes in HCC patients.3o7rdHzTehVwN25qa8k-ATVideo

Identification and validation of cancer-associated fibroblast-related subtypes and the prognosis model of biochemical recurrence in prostate cancer based on single-cell and bulk RNA sequencing.

Cancer-associated fibroblasts (CAFs) are an essential component of the tumor immune microenvironment that are involved in extracellular matrix (ECM) remodeling. We aim to investigate the characteristics of CAFs in prostate cancer and develop a biochemical recurrence (BCR)-related CAF signature for predicting the prognosis of PCa patients. The bulk RNA-seq and relevant clinical information were obtained from the TCGA and GEO databases, respectively. The infiltration scores of CAFs in prostate cancer patients were calculated using the MCP counter and EPIC algorithms. The single-cell RNA sequencing (scRNA-seq) was downloaded from the GEO database. Subsequently, univariate Cox regression analysis was employed to identify prognostic genes associated with CAFs. We identified two subtypes (C1 and C2) of prostate cancer that were associated with CAFs via non-negative matrix factorization (NMF) clustering. In addition, the BCR-related CAF signatures were constructed using Lasso regression analysis. Finally, a nomogram model was established based on the risk score and clinical characteristics of the patients. Initially, we found that patients with high CAF infiltration scores had shorter biochemical recurrence-free survival (BCRFS) times. Subsequently, CAFs in four pairs of tumors and paracancerous tissues were identified. We discovered 253 significantly differentially expressed genes, of which 13 had prognostic significance. Using NMF clustering, we divided PCa patients into C1 and C2 subgroups, with the C1 subgroup having a worse prognosis and substantially enriched cell cycle, homologous recombination, and mismatch repair pathways. Furthermore, a BCR-related CAFs signature was established. Multivariate COX regression analysis confirmed that the BCR-related CAFs signature was an independent prognostic factor for BCR in PCa. In addition, the nomogram was based on the clinical characteristics and risk scores of the patient and demonstrated high accuracy and reliability for predicting BCR. Lastly, our findings indicate that the risk score may be a useful tool for predicting PCa patients' sensitivity to immunotherapy and drug treatment. NMF clustering based on CAF-related genes revealed distinct TME immune characteristics between groups. The BCR-related CAF signature accurately predicted prognosis and immunotherapy response in prostate cancer patients, offering a promising new approach to cancer treatment.

Cancer-associated fibroblast infiltration in osteosarcoma: the discrepancy in subtypes pathways and immunosuppression.

Introduction: Osteosarcoma (OS), the primary malignant bone tumor, has a low survival rate for recurrent patients. Latest reports indicated that cancer-associated fibroblasts (CAFs) were the main component of tumor microenvironment, and would generate a variable role in the progression of tumors. However, the role of CAFs is still few known in osteosarcoma. Methods: The processed RNA-seq data and the corresponding clinical and molecular information were retrieved from the Cancer Genome Atlas Program (TCGA) database and processed data of tumor tissue was obtained from Gene Expression Omnibus (GEO) database. Xcell method was used in data processing, and Gene set variation analysis (GSVA) was used to calculates enrichment scores. Nomogram was constructed to evaluate prognostic power of the predictive model. And the construction of risk scores and assessment of prognostic predictive were based on the LASSO model. Results: This study classified Cancer Genome Atlas (TCGA) cohort into high and low CAFs infiltrate phenotype with different CAFs infiltration enrichment scores. Then TOP 9 genes were screened as prognostic signatures among 2,488 differentially expressed genes between the two groups. Key prognostic molecules were CGREF1, CORT and RHBDL2 and the risk score formula is: Risk-score = CGREF1*0.004 + CORT*0.004 + RHBDL2*0.002. The signatures were validated to be independent prognostic factors to predict tumor prognosis with single-factor COX and multi-factor COX regression analyses and Norton chart. The risk score expression of risk score model genes could predict the drug resistance, and significant differences could be found between the high and low scoring groups for 17-AAG, AZD6244, PD-0325901 and Sorafenib. Discussion: To sum up, this article validated the prediction role of CAF infiltration in the prognosis of OS, which might shed light on the treatment of OS.