Hepatocellular carcinoma (HCC) is a lethal form of liver cancer, and the tumor microenvironment, particularly cancer-associated fibroblasts (CAFs), plays a critical role in its progression. This study aimed to elucidate the mechanism by which CAF-derived exosomes regulate the development of HCC. The study employed quantitative real-time polymerase chain reaction for mRNA expression analysis and western blot analysis for protein expression detection. Chromatin immunoprecipitation assay and dual-luciferase reporter assay were performed to investigate the relationship between zinc finger protein 250 (ZNF250) and programmed cell death 1 ligand 1 (PD-L1). Transmission electron microscopy and western blot analysis were used to characterize the isolated exosomes. The transferability of CAF-derived exosomes and normal fibroblasts (NFs)-derived exosomes into HCC cells was analyzed using a green fluorescent labeling dye PKH67. Cell proliferation was assessed via a 5-Ethynyl-2\'-deoxyuridine assay, while Transwell assays were conducted to evaluate cell migration and invasion. Flow cytometry was performed to measure cell apoptosis, while enzyme-linked immunosorbent assays were used to assess the levels of tumor necrosis factor-α and perforin. Finally, a xenograft mouse model was constructed to examine the effects of exosomes derived from ZNF250-deficient CAFs on the tumor properties of HCC cells. The study revealed increased expression of ZNF250 in HCC tissues and cells, with ZNF250 transcriptionally activating PD-L1 in HCC cells. ZNF250 expression was associated with HbsAg, clinical stage and tumor size of HCC patients. CAF-derived exosomal ZNF250 can regulate PD-L1 expression in HCC cells. Furthermore, exosomes derived from ZNF250-deficient CAFs inhibited the proliferation, migration, invasion, and immune escape of HCC cells by downregulating PD-L1 expression. Moreover, CAF-derived exosomal ZNF250 promoted tumor formation in vivo. These findings provide insights into the role of CAF-derived exosomes in the suppression of HCC development, highlighting the significance of ZNF250 and PD-L1 regulation in tumor progression.

Currently, the oncogenic mechanism of endoplasmic reticulum stress-CAF (ERS-CAF) subpopulation in chordoma remains unknown. Here, single-cell RNA sequencing, spatial transcriptomics, GeoMx Digital Spatial Profiler, data-independent acquisition proteomics, bulk RNA-seq, and multiplexed quantitative immunofluorescence are used to unveil the precise molecular mechanism of how ERS-CAF affected chordoma progression. Results show that hypoxic microenvironment reprograms CAFs into ERS-CAF subtype. Mechanistically, this occurrs via hypoxia-mediated transcriptional upregulation of IER2. Overexpression of IER2 in CAFs promotes chordoma progression, which can be impeded by IER2 knockdown or use of ERS inhibitors. IER2 also induces expression of ERS-CAF marker genes and results in production of a pro-tumorigenic paracrine GMFG signaling, which exert its biological function via directly binding to ITGB1 on tumor cells. ITGB1 inhibition attenuates tumor malignant progression, which can be partially reversed by exogenous GMFG intervention. Further analyses reveal a positive correlation between ITGB1high tumor cell counts and SPP1+ macrophage density, as well as the spatial proximity of these two cell types. Clinically, a significant correlation of high IER2/ITGB1 expression with tumor aggressive phenotype and poor patient survival is observed. Collectively, the findings suggest that ERS-CAF regulates SPP1+ macrophage to aggravate chordoma progression via the IER2/GMFG/ITGB1 axis, which may be targeted therapeutically in future.

Metastasis is a crucial stage in tumour progression, and cancer-associated fibroblasts (CAFs) support metastasis through their participation in extracellular matrix (ECM) stiffness. CD248 is a possible biomarker for non-small cell lung cancer (NSCLC)-derived CAFs, but its role in mediating ECM stiffness to promote NSCLC metastasis is unknown. We investigated the significance of CD248+ CAFs in activating the Hippo axis and promoting connective tissue growth factor (CTGF) expression, which affects the stromal collagen I environment and improves ECM stiffness, thereby facilitating NSCLC metastasis. In this study, we found that higher levels of CD248 in CAFs induced the formation of collagen I, which in turn increased extracellular matrix stiffness, thereby enabling NSCLC cell infiltration and migration. Hippo axis activation by CD248+ CAFs induces CTGF expression, which facilitates the formation of the collagen I milieu in the stromal matrix. In a tumour lung metastasis model utilizing fibroblast-specific CD248 gene knockout mice, CD248 gene knockout mice showed a significantly reduced ability to develop tumour lung metastasis compared to that of WT mice. Our findings demonstrate that CD248+ CAFs activate the Hippo pathway, thereby inducing CTGF expression, which in turn facilitates the collagen I milieu of the stromal matrix, which promotes NSCLC metastasis.

OBJECTIVE: Cancer-associated fibroblasts (CAFs) are abundant in colon cancer (CC) patients with a poor prognosis. Here, the molecular regulatory mechanism of CAFs on CC growth and metastasis was explored.
METHODS: The genes\' expression was monitored using RT-qPCR, immunoblotting, and immunohistochemistry. Cell viability and proliferation were found using CCK-8 and clone formation assays. The cell migration and invasion were probed using wound healing and Transwell. Co-IP was utilized for ascertaining the interaction between AKT and the ring finger protein, LIM domain interacting (RLIM). The in vivo murine subcutaneous tumor model and the metastasis model were built to further ascertain the axis.
RESULTS: The result showed that CAFs motivate the growth and activate the PI3K/AKT pathway of CC cells via paracrine cartilage oligomeric matrix protein (COMP). Moreover, RLIM promoted the growth of CC cells, and its protein stability was regulated by AKT through its phosphorylation. Further, RLIM facilitated the ubiquitination and degradation of promyelocytic leukemia protein (PML). The in vitro and in vivo tests found that PML overexpression could inhibit CC\'s growth and metastasis, which were enhanced by CAFs.
CONCLUSIONS: The COMP excreted from CAFs enhances the CC\'s growth and metastasis through regulating the RLIM/PML axis, supplying a new potential target for the cure of CC.

OBJECTIVE: 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.
METHODS: 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.
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-β dependent manner.
CONCLUSIONS: 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.

Acquired resistance is a major obstacle to the therapeutic efficacy of osimertinib in lung adenocarcinoma (LUAD), but the underlying mechanisms are still not fully understood. Cancer-associated fibroblasts (CAFs) are the most abundant stromal cell type in LUAD tumor-microenvironment (TME) and have emerged as a key player in chemoresistance. However, the function of CAFs in osimertinib resistance is still unclear. Here, we showed that CAFs derived from osimertinib-resistant LUAD tissues (CAFOR) produced much more colony-stimulating factor 2 (CSF2) than those isolated from osimertinib-sensitive tissues. CAFOR-derived CSF2 activated the Janus kinase 2 (JAK2)/Signal transducer and activator of transcription 3 (STAT3) signaling pathway and upregulated lnc-CSRNP3 in LUAD cells. Lnc-CSRNP3 then promoted the expression of nearby gene CSRNP3 by recruiting chromodomain helicase DNA binding protein 9 (CHD9) and inhibited the phosphatase activity of the serine/threonine protein phosphatase 1 catalytic subunit α (PP1α), thereby induced osimertinib resistance by enhancing ribosome biogenesis. Collectively, our study reveals a critical role for CAFs in the development of osimertinib resistance and identifies the CSF2 pathway as an attractive target for monitoring osimertinib efficacy and overcoming osimertinib resistance in LUAD.

A key characteristic of cancer cells is their ability to induce changes in their microenvironment that render it permissive to tumor growth, invasion and metastasis. Indeed, these changes are required for tumor progression. Consequently, the tumor microenvironment is emerging as a key source of new targets against cancer, with novel therapies aimed at reversing tumor-promoting changes, reinstating a tumor-hostile microenvironment and suppressing disease progression. RHO-ROCK signaling, and consequent tension within the cellular actomyosin cytoskeleton, regulates a paracrine signaling cascade that establishes a tumor-promoting microenvironment. Here, we show that consistent with our observations in breast cancer, enhanced ROCK activity and consequent production of CRELD2 is associated with the recruitment and tumor-promoting polarization of cancer-associated fibroblasts in cutaneous squamous cell carcinoma. Our observations provide support for the notion that the role of RHO-ROCK signaling in establishing a tumor-promoting microenvironment may be conserved across patients and potentially also different cancer types.

The specificity and clinical relevance of cancer-associated fibroblasts (CAFs) in prostate cancer (PCa), as well as the effect of androgen deprivation therapy (ADT) on CAFs, remain to be fully elucidated. Using cell lineage diversity and weighted gene co-expression network analysis (WGCNA), we pinpointed a unique CAF signature exclusive to PCa. The specificity of this CAF signature was validated through single-cell RNA sequencing (scRNA-seq), cell line RNA sequencing, and immunohistochemistry. This signature associates CAFs with tumor progression, elevated Gleason scores, and the emergence of castration resistant prostate cancer (CRPC). Using scRNA-seq on collected samples, we demonstrated that the CAF-specific signature is not altered by ADT, maintaining its peak signal output. Identifying a PCa-specific CAF signature and observing signaling changes in CAFs after ADT lay essential groundwork for further PCa studies.

Cancer-associated fibroblasts (CAFs) are a major cellular component in the tumor microenvironment and have been shown to exhibit protumorigenic effects in hepatocellular carcinoma (HCC). This study aimed to delve into the mechanisms underlying the tumor-promoting effects of CAFs in HCC. Small RNA sequencing was conducted to screen differential expressed microRNAs in exosomes derived from CAFs and normal fibroblasts (NFs). The miR-92a-3p expression was then measured using reverse transcriptase quantitative real-time PCR in CAFs, NFs, CAFs-derived exosomes (CAFs-Exo), and NF-derived exosomes (NFs-Exo). Compared to NFs or NF-Exo, CAFs and CAFs-Exo significantly promoted HCC cell proliferation, migration, and stemness. Additionally, compared to NFs or NF-Exo, miR-92a-3p level was notably higher in CAFs and CAFs-Exo, respectively. Exosomal miR-92a-3p was found to enhance HCC cell proliferation, migration, and stemness. Meanwhile, AXIN1 was targeted by miR-92a-3p. Exosomal miR-92a-3p could activate β-catenin/CD44 signaling in HCC cells by inhibiting AXIN1 messenger RNA. Furthermore, in vivo studies verified that exosomal miR-92a-3p notably promoted tumor growth and stemness through targeting AXIN1/β-catenin axis. Collectively, CAFs secreted exosomal miR-92a-3p was capable of promoting growth and stemness in HCC through activation of Wnt/β-catenin signaling pathway by suppressing AXIN1. Therefore, targeting CAFs-derived miR-92a-3p may be a potential strategy for treating HCC.

Cancer-associated fibroblasts (CAFs) are abundant and heterogeneous stromal cells in the tumor microenvironment, which play important roles in regulating tumor progression and therapy resistance by transferring exosomes to cancer cells. However, how CAFs modulate esophageal squamous cell carcinoma (ESCC) progression and radioresistance remains incompletely understood. The expression of fibroblast activation protein (FAP) in CAFs was evaluated by immunohistochemistry in 174 ESCC patients who underwent surgery and 78 pretreatment biopsy specimens of ESCC patients who underwent definitive chemoradiotherapy. We sorted CAFs according to FAP expression, and the conditioned medium (CM) was collected to culture ESCC cells. The expression levels of several lncRNAs that were considered to regulate ESCC progression and/or radioresistance were measured in exosomes derived from FAP+ CAFs and FAP- CAFs. Subsequently, cell counting kit-8, 5-ethynyl-2\'-deoxyuridine, transwell, colony formation, and xenograft assays were performed to investigate the functional differences between FAP+ CAFs and FAP- CAFs. Finally, a series of in vitro and in vivo assays were used to evaluate the effect of AFAP1-AS1 on radiosensitivity of ESCC cells. FAP expression in stromal CAFs was positively correlated with nerve invasion, vascular invasion, depth of invasion, lymph node metastasis, lack of clinical complete response and poor survival. Culture of ESCC cells with CM/FAP+ CAFs significantly increased cancer proliferation, migration, invasion and radioresistance, compared with culture with CM/FAP- CAFs. Importantly, FAP+ CAFs exert their roles by directly transferring the functional lncRNA AFAP1-AS1 to ESCC cells via exosomes. Functional studies showed that AFAP1-AS1 promoted radioresistance by enhancing DNA damage repair in ESCC cells. Clinically, high levels of plasma AFAP1-AS1 correlated with poor responses to dCRT in ESCC patients. Our findings demonstrated that FAP+ CAFs promoted radioresistance in ESCC cells through transferring exosomal lncRNA AFAP1-AS1; and may be a potential therapeutic target for ESCC treatment.