Expression Of Colony Stimulating Factor-1 Research Articles

Dorsal root ganglia CSF1+ neuronal subtypes have different impact on macrophages and microglia after spared nerve injury.

Colony-stimulating factor 1 (CSF1) is a growth factor secreted by dorsal root ganglia (DRG) neurons important for DRG macrophages and spinal cord (SC) microglia injury-induced proliferation and activation, specifically released after spared nerve injury (SNI). In this study, we investigated if SNI-induced CSF1 expression and perineuronal rings of macrophages around mouse DRG neurons vary between L3-L5 DRG and with the neuronal type, and if the CSF1+ neuronal projections at the SC dorsal horns were associated with an increased microglial number in the corresponding laminae. Seven days after surgery, L3-L5 DRG as well as their corresponding segments at the SC level were collected, frozen, and cut. DRG sections were double-immunostained using antibodies against CSF1 and NF200, CGRP or IB4, while SC sections were immunostained using a fluorescent Nissl Stain and analyzed for CX3CR1-GFP microglia number and distribution by an in-house ImageJ Plug-in. Our results showed that SNI-induced CSF1 expression was common for all subtypes of mouse DRG neurons, being responsible for attracting more resident macrophages around them in a DRG-dependent manner, with L4 showing the stronger response and CSF1+/NF200+ neurons showing the highest incidence. Even though the total number of microglia in the SC ipsilateral dorsal horns increased after SNI, the increase at their specific laminar projection sites did not mirror the incidence of DRG neuronal subtypes among CSF1+ neurons. Taken together, these results contribute to a more comprehensive understanding of the connection between CSF1 and macrophage/microglia response after SNI and emphasize the importance of considering L3-L5 DRG individually when investigating SNI-neuropathic pain pathogenesis in mice.

Evaluation of Tumour-Associated Macrophages and Colony-Stimulating Factor-1 Expression in Invasive Breast Carcinoma and Their Association with Prognostic Parameters

INTRODUCTION: Recent breast cancer research has focused on tumour microenvironment (TME). Tumour-associated macrophages (TAMs) are the key players in TME as they provide pro-tumorigenic milieu for tumour progression and metastasis. These macrophages are primarily regulated by colony-stimulating factor-1 (CSF-1) secreted by breast cancer cells. This study investigated the association of localization of TAMs infiltration within breast carcinoma and CSF-1 expression by cancer cells with the pathological prognostic parameters. MATERIALS AND METHODS: TAMs were assessed in 128 cases of invasive breast carcinoma by CD163 immunohistochemical expression. The median TAM density in both the tumour nest and tumour stroma was utilized to classify TAMs into categories of low and high infiltration. The cancer cells were immunostained with anti-CSF-1 antibody and the staining intensity was evaluated as low or high expression. RESULTS: High nest and stromal TAMs were associated with higher tumour grades (p=0.005 and p=0.0001, respectively) whereas only high stromal TAMs showed significant association with negative oestrogen and progesterone receptors status (p=0.001 and 0.001, respectively); and triple-negative subtype (p=0.002). High CSF-1 expression was significantly associated with high stromal TAMs (p=0.031). High CSF-1 expression was associated with tumour grade and positive HER2 status (p=0.008 and 0.007, respectively). CONCLUSION: TAMs in tumour nest and stroma showed varying degrees of association with the clinicopathological parameters. High CSF-1 expression was associated with unfavourable prognostic parameters. Therefore, the evaluation of TAMs and CSF-1 expressions could potentially serve as prognostic markers and cellular targets for novel treatment modality in invasive breast cancers.

Baricitinib ameliorates inflammatory and neuropathic pain in collagen antibody-induced arthritis mice by modulating the IL-6/JAK/STAT3 pathway and CSF-1 expression in dorsal root ganglion neurons

BackgroundJanus kinase (JAK) inhibitors, such as baricitinib, are widely used to treat rheumatoid arthritis (RA). Clinical studies show that baricitinib is more effective at reducing pain than other similar drugs. Here, we aimed to elucidate the molecular mechanisms underlying the pain relief conferred by baricitinib, using a mouse model of arthritis.MethodsWe treated collagen antibody-induced arthritis (CAIA) model mice with baricitinib, celecoxib, or vehicle, and evaluated the severity of arthritis, histological findings of the spinal cord, and pain-related behaviours. We also conducted RNA sequencing (RNA-seq) to identify alterations in gene expression in the dorsal root ganglion (DRG) following baricitinib treatment. Finally, we conducted in vitro experiments to investigate the direct effects of baricitinib on neuronal cells.ResultsBoth baricitinib and celecoxib significantly decreased CAIA and improved arthritis-dependent grip-strength deficit, while only baricitinib notably suppressed residual tactile allodynia as determined by the von Frey test. CAIA induction of inflammatory cytokines in ankle synovium, including interleukin (IL)-1β and IL-6, was suppressed by treatment with either baricitinib or celecoxib. In contrast, RNA-seq analysis of the DRG revealed that baricitinib, but not celecoxib, restored gene expression alterations induced by CAIA to the control condition. Among many pathways changed by CAIA and baricitinib treatment, the interferon-alpha/gamma, JAK-signal transducer and activator of transcription 3 (STAT3), and nuclear factor kappa B (NF-κB) pathways were considerably decreased in the baricitinib group compared with the celecoxib group. Notably, only baricitinib decreased the expression of colony-stimulating factor 1 (CSF-1), a potent cytokine that causes neuropathic pain through activation of the microglia–astrocyte axis in the spinal cord. Accordingly, baricitinib prevented increases in microglia and astrocytes caused by CAIA. Baricitinib also suppressed JAK/STAT3 pathway activity and Csf1 expression in cultured neuronal cells.ConclusionsOur findings demonstrate the effects baricitinib has on the DRG in relation to ameliorating both inflammatory and neuropathic pain.

Colony stimulating factor-1 (CSF-1) signalling is predictive of response to immune checkpoint inhibitors in advanced non-small cell lung cancer

The identification of biomarkers related to treatment in patients with non-small cell lung cancer (NSCLC) treated with immune checkpoint inhibitors (ICIs) represents a significant challenge. The aim of this study was to determine the predictive value of macrophage-related markers assessed in plasma and tissue samples of patients with NSCLC undergoing ICI treatment. This bicentric study included a prospective cohort of 88 patients with advanced NSCLC who received first-line therapy with ICI (either as monotherapy or in combination with chemotherapy) or chemotherapy alone (CT). Samples were collected from the patients at baseline and during follow-up. Plasma levels of CSF-1 and IL-34 were measured using ELISA, while expression levels of the macrophage receptors CD163 and CSF-1-R were evaluated using immunohistochemistry on lung biopsies. At baseline, the median plasma CSF-1 expression was higher in patients who did not respond to immunotherapy compared to those who responded (8898 pg/mL vs. 14031 pg/mL, p = 0.0005). Importantly, high CSF-1 levels at the initial assessment were associated with disease progression regardless of the treatment received. Furthermore, high CSF-1 levels were associated with shorter progression-free survival (PFS) and overall survival (OS) in patients receiving ICI therapy, but not in those treated with chemotherapy. There was no correlation between IL-34, CSF-1R, CD163 and therapeutic response. We observed in vitro that the activation of lymphocytes mediated by pembrolizumab was hindered by the treatment of PBMC with recombinant CSF-1, suggesting that CSF-1 creates a systemic immunosuppressive state that interferes with ICI treatment. In conclusion, baseline CSF-1 levels represent a potential predictive marker to ICI treatment in NSCLC.

Inhibition of inflammation and infiltration of M2 macrophages in NSCLC through the ATF3/CSF1 axis: Role of miR-27a-3p.

Non-small cell lung cancer (NSCLC) imposes a significant economic burden on patients and society due to its low overall cure and survival rates. Tumour-associated macrophages (TAM) affect tumour development and may be a novel therapeutic target for cancer. We collected NSCLC and tumour-adjacent tissue samples. Compared with the tumour-adjacent tissues, the Activation Transcription Factor 3 (ATF3) and Colony Stimulating Factor 1 (CSF-1) were increased in NSCLC tissues. Levels of ATF3 and CSF-1 were identified in different cell lines (HBE, A549, SPC-A-1, NCI-H1299 and NCI-H1795). Overexpression of ATF3 in A549 cells increased the expression of CD68, CD206 and CSF-1. Moreover, levels of CD206, CD163, IL-10 and TGF-β increased when A549 cells were co-cultured with M0 macrophages under the stimulation of CSF-1. Using the starbase online software prediction and dual-luciferase assays, we identified the targeting between miR-27a-3p and ATF3. Levels of ATF3, CSF-1, CD206, CD163, IL-10 and TGF-β decreased in the miR-27a mimics, and the tumour growth was slowed in the miR-27a mimics compared with the mimics NC group. Overall, the study suggested that miR-27a-3p might inhibit the ATF3/CFS1 axis, regulate the M2 polarization of macrophages and ultimately hinder the progress of NSCLC. This research might provide a new therapeutic strategy for NSCLC.

Gene Expression Levels of CSF-1 and CSF-1R Endometrial under The Influence of Prolactin Level in Unexplained Miscarriage: A Case-Control Study.

Hormones such as prolactin, by influencing expression of the endometrial genes, play a pivotal role in embryo implantation and development. The present study aimed to evaluate serum level of prolactin and its effect on altering expression level of colony-stimulating factor-1 (CSF-1) and colony-stimulating factor-1 receptor (CSF-1R) genes in endometrial tissue during in vitro fertilization (IVF) pregnancy in the infertile women and recurrent pregnancy loss (RPL), compared to fertile women, who lost their pregnancies at gestational age <20 weeks. In this case-control study, 40 infertile women, 40 IVF pregnant women with RPL and 40 fertile women who lost their pregnancies at <20 weeks of gestation for unknown reasons were selected. Prolactin serum level was assessed using ELISA technique and expression of CSF-1 and CSF-1R genes was determined in endometrial tissue, using quantitative reverse transcription polymerase chain reaction (qRT-PCR). Mean prolactin level of the infertile group was 24.38 ± 1.43 ng/mL and it had statistically significant relationship with the fertile group (P<0.001). Expression level of the CSF-1 and CSF-1R genes were higher in the fertile than infertile groups by 2.88 times (P<0.0001) and 2.64 times (P<0.0001), while it was respectively 2.28 (P<0.0001) and 1.69 (P<0.0001) times higher compared to the RPL group. Risk factors for pregnancy loss, such as aging, increased body mass index (BMI), smoking and diabetes caused decreasing changes in gene expression (CSF-1 and CSF-1R ) and the differences were statistically significant, except in the infertile group. The present study showed a significant relationship of CSF-1 and CSF-1R expression levels with pregnancy loss. Risk factors such as aging, obesity, smoking and diabetes decreased both genes expression levels.

Decreased melanoma CSF-1 secretion by Cannabigerol treatment reprograms regulatory myeloid cells and reduces tumor progression

ABSTRACT During solid tumor progression, the tumor microenvironment (TME) evolves into a highly immunosuppressive milieu. Key players in the immunosuppressive environment are regulatory myeloid cells, including myeloid-derived suppressor cells (MDSCs) and tumor-associated macrophages (TAMs), which are recruited and activated via tumor-secreted cytokines such as colony-stimulating factor 1 (CSF-1). Therefore, the depletion of tumor-secreted cytokines is a leading anticancer strategy. Here, we found that CSF-1 secretion by melanoma cells is decreased following treatment with Cannabis extracts. Cannabigerol (CBG) was identified as the bioactive cannabinoid responsible for the effects. Conditioned media from cells treated with pure CBG or the high-CBG extract reduced the expansion and macrophage transition of the monocytic-MDSC subpopulation. Treated MO-MDSCs also expressed lower levels of iNOS, leading to restored CD8+ T-cell activation. Tumor-bearing mice treated with CBG presented reduced tumor progression, lower TAM frequencies and reduced TAM/M1 ratio. A combination of CBG and αPD-L1 was more effective in reducing tumor progression, enhancing survival and increasing the infiltration of activated cytotoxic T-cells than each treatment separately. We show a novel mechanism for CBG in modulating the TME and enhancing immune checkpoint blockade therapy, underlining its promising therapeutic potential for the treatment of a variety of tumors with elevated CSF-1 expression.

Matrix stiffness enhances cancer-macrophage interactions and M2-like macrophage accumulation in the breast tumor microenvironment.

The role of intratumor heterogeneity is becoming increasingly apparent in part due to expansion in single cell technologies. Clinically, tumor heterogeneity poses several obstacles to effective cancer therapy dealing with biomarker variability and treatment responses. Matrix stiffening is known to occur during tumor progression and contribute to pathogenesis in several cancer hallmarks, including tumor angiogenesis and metastasis. However, the effects of matrix stiffening on intratumor heterogeneity have not been thoroughly studied. In this study, we applied single-cell RNA sequencing to investigate the differences in the transcriptional landscapes between stiff and compliant MMTV-PyMT mouse mammary tumors. We found similar compositions of cancer and stromal subpopulations in compliant and stiff tumors but differential intercellular communication and a significantly higher concentration of tumor-promoting, M2-like macrophages in the stiffer tumor microenvironments. Interestingly, we found that cancer cells seeded on stiffer substrates recruited more macrophages. Furthermore, elevated matrix stiffness increased Colony Stimulating Factor 1 (CSF-1) expression in breast cancer cells and reduction of CSF-1 expression on stiffer substrates reduced macrophage recruitment. Thus, our results demonstrate that tissue phenotypes were conserved between stiff and compliant tumors but matrix stiffening altered cell-cell interactions which may be responsible for shifting the phenotypic balance of macrophages residing in the tumor microenvironment towards a pro-tumor progression M2 phenotype. STATEMENT OF SIGNIFICANCE: Cells within tumors are highly heterogeneous, posing challenges with treatment and recurrence. While increased tissue stiffness can promote several hallmarks of cancer, its effects on tumor heterogeneity are unclear. We used single-cell RNA sequencing to investigate the differences in the transcriptional landscapes between stiff and compliant MMTV-PyMT mouse mammary tumors. We found similar compositions of cancer and stromal subpopulations in compliant and stiff tumors but differential intercellular communication and a significantly higher concentration of tumor-promoting, M2-like macrophages in the stiffer tumor microenvironments. Using a biomaterial-based platform, we found that cancer cells seeded on stiffer substrates recruited more macrophages, supporting our in vivo findings. Together, our results demonstrate a key role of matrix stiffness in affecting cell-cell communication and macrophage recruitment.

Increased expression of CSF1 in patients with eosinophilic asthma.

The link between colony-stimulating factor 1 (CSF1) and asthma was reported recently. However, the role and mechanism of CSF1 in asthma remain poorly understood. In this study, we aimed to explore the expression and its potential mechanism of CSF1 in asthma. CSF1 expression in the airway samples from asthmatics and healthy controls were examined, then the correlations between CSF1 and eosinophilic indicators were analyzed. Subsequently, bronchial epithelial cells (BEAS-2B) with CSF1 overexpression and knockdown were constructed to investigate the potential molecular mechanism of CSF1. Finally, the effect of CSF1R inhibitor on STAT1 was investigated. The expression of CSF1 was significantly increased in patients with asthma compared to healthy controls, especially in patients with severe and eosinophilic asthma. Upregulated CSF1 positively correlated with airway-increased eosinophil inflammation. In vitro, cytokines interleukin 13(IL-13) and IL-33 can stimulate the upregulation of CSF1 expression. CSF1 overexpression enhanced p-CSF1R/CSF1R and p-STAT1/STAT1 expression, while knockdown CSF1 using anti-CSF1 siRNAs decreased p-CSF1R/CSF1R and p-STAT1/STAT1 expression. Furthermore, the inhibitor of CSF1R significantly decreased p-STAT1/STAT1 expression. Sputum CSF1 may be involved in asthmatic airway eosinophil inflammation by interacting with CSF1R and further activating the STAT1 signaling. Interfering this potential pathway could serve as an anti-inflammatory therapy for asthma.

Abstract 1289: The role of mutant p53-mediated mechanisms in modulating the tumor microenvironment and promoting lung metastasis

Abstract INTRODUCTION/METHODS: The multistep process of the tumor invasion-metastasis cascade is a major barrier to effective therapy. Mutations of the tumor suppressor p53 are frequently detected in esophageal squamous cell carcinoma (ESCC) cases, which in turn correlate with high metastatic rates. To understand the mutant p53-mediated mechanisms in promoting ESCC metastasis, we conducted RNA-Seq, ChIP-Seq and cytokine array on isogenic primary and metastatic tumor cells harvested from our mouse model of esophageal cancer, L2-Cre; LSL-Trp53R172H; Rosa26LSL-YFP, in which we have identified macrophage colony stimulating factor 1 (CSF1) to be a direct gene target of p53-R172H. We have targeted CSF1/CSF1R signaling to assess its pro-tumorigenic roles. In addition to studying tumor intrinsic mechanisms, we have established multiplex immunofluorescence and flow cytometry approaches to characterize the changes in tumor microenvironment (TME). Overall, this study aims to investigate the role and mediators of CSF1 signaling through its cognate receptor CSF1R by which missense p53 mutations can promote lung metastasis. RESULTS/DISCUSSION: We demonstrate that metastatic ESCC has increased Csf1 expression compared to primary tumors and this is dependent upon p53 mutation status, which is reinforced by TCGA data and patient-derived tissue microarrays (TMAs). The TMA analysis also suggested that CSF1 expression is higher in tumors that are poorly differentiated. Furthermore, through the proximity ligation assay (PLA), we have identified that bromodomain and extra-terminal (BET) protein BRD4, which binds to acetylated histones to regulate transcription interacts with p53-R172H at higher levels compared to wild-type p53 to induce Csf1 expression. We show that the BRD4/CSF1/CSF1R signaling axis fosters tumor invasion, subcutaneous tumor growth and metastatic burden in lungs in a mutant p53 background. In accordance, targeting CSF1/CSF1R signaling reduces phosphorylation of STAT3 in the metastatic tumors, which suggests a mechanism for increased invasiveness and metastasis. In parallel, upon inhibiting this axis, we have identified decreased infiltration of F4/80+CD163+ and F4/80+CD206+ M2-polarized macrophages, as well as CD31+ endothelial cells, and increased number of CD3+CD8+ cytotoxic T-cells at the metastatic tumor sites, indicating that the CSF1/CSF1R pathway plays a critical role in shaping the pro-metastatic and immunosuppressive TME. Finally, analysis of squamous cell carcinoma (SCC) datasets reveals that specific p53 mutations are associated with differential survival rates and CSF1 expression. CONCLUSION: We have demonstrated novel roles and mechanisms of mutant p53-dependent CSF1-CSF1R signaling pathway in fostering ESCC tumor invasion and lung metastasis that may be applicable to other SCCs. We believe this can open up new avenues for therapeutic applications. Citation Format: Gizem Efe, Katherine M. Cunningham, Qiaosi Tang, Kensuke Sugiura, Karen Dunbar, Kensuke Suzuki, Lois Resnick-Silverman, Alison M. Taylor, James J. Manfredi, Carol L. Prives, Anil K. Rustgi. The role of mutant p53-mediated mechanisms in modulating the tumor microenvironment and promoting lung metastasis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 1289.

Diagnostic utility of CSF1 immunohistochemistry in tenosynovial giant cell tumor for differentiating from giant cell-rich tumors and tumor-like lesions of bone and soft tissue

BackgroundTenosynovial giant cell tumor (TSGCT) is a benign fibrohistiocytic tumor that affects the synovium of joints, bursa, and tendon sheaths and is categorized into localized TSGCT (LTSGCT) and diffuse TSGCT (DTSGCT). LTSGCT and DTSGCT are characterized by recurrent fusions involving the colony-stimulating factor 1 (CSF1) gene and its translocation partner collagen type VI alpha 3 chain. The fusion gene induces intratumoral overexpression of CSF1 mRNA and CSF1 protein. CSF1 expression is a characteristic finding of TSGCT and detection of CSF1 mRNA and CSF1 protein may be useful for the pathological diagnosis. Although there have been no effective anti-CSF1 antibodies to date, in situ hybridization (ISH) for CSF1 mRNA has been performed to detect CSF1 expression in TSGCT. We performed CSF1 immunohistochemistry (IHC) using anti-CSF1 antibody (clone 2D10) in cases of TSGCT, giant cell-rich tumor (GCRT), and GCRT-like lesion and verified its utility for the pathological diagnosis of TSGCT.MethodsWe performed CSF1 IHC in 110 cases including 44 LTSGCTs, 20 DTSGCTs, 1 malignant TSGCT (MTSGCT), 10 giant cell tumors of bone, 2 giant cell reparative granulomas, 3 aneurysmal bone cysts, 10 undifferentiated pleomorphic sarcomas, 10 leiomyosarcomas, and 10 myxofibrosarcomas. We performed fluorescence ISH (FISH) for CSF1 rearrangement to confirm CSF1 expression on IHC in TSGCTs. We considered the specimens to have CSF1 rearrangement if a split signal was observed in greater than 2% of the tumor cells.ResultsOverall, 50 of 65 TSGCT cases, including 35 of the 44 LTSGCTs and 15 of the 20 DTSGCTs, showed distinct scattered expression of CSF1 in the majority of mononuclear tumor cells. MTSGCT showed no CSF1 expression. Non-TSGCT cases were negative for CSF1. FISH revealed CSF1 rearrangement in 6 of 7 CSF1-positive cases on IHC. On the other hand, FISH detected no CSF1 rearrangement in all CSF1-negative cases on IHC. Thus, the results of IHC corresponded to those of FISH.ConclusionWe revealed characteristic CSF1 expression on IHC in cases of TSGCT, whereas the cases of non-TSGCT exhibited no CSF1 expression. CSF1 IHC may be useful for differentiating TSGCTs from histologically mimicking GCRTs and GCRT-like lesions.

475P Safety and efficacy of vimseltinib in tenosynovial giant cell tumour (TGCT): Long-term phase I update

TGCT is a rare, locally aggressive neoplasm caused by upregulation of the colony-stimulating factor 1 (CSF1) gene, resulting in aberrant CSF1 expression and the recruitment of CSF1 receptor (CSF1R)-dependent inflammatory macrophages. Vimseltinib is an oral switch-control tyrosine kinase inhibitor specifically designed to selectively and potently inhibit CSF1R. We report long-term safety and efficacy for patients (pts) with TGCT from the phase I arm (dose escalation) of the phase I/II study.

1509P Efficacy and safety of vimseltinib in tenosynovial giant cell tumour (TGCT): Phase II expansion

TGCT is a rare, locally aggressive neoplasm caused by upregulation of the colony-stimulating factor 1 (CSF1) gene, resulting in aberrant CSF1 expression and recruitment of CSF1 receptor (CSF1R)-dependent inflammatory macrophages. Vimseltinib is an oral switch control tyrosine kinase inhibitor specifically designed to selectively and potently inhibit CSF1R. We report safety, efficacy, and preliminary patient-reported outcome data for patients (pts) with TGCT treated with the recommended phase 2 dose (RP2D; 30 mg twice weekly).

MOTION: A randomized, phase 3, placebo-controlled, double-blind study of vimseltinib (DCC-3014) for the treatment of tenosynovial giant cell tumor.

TPS11590 Background: Tenosynovial giant cell tumor (TGCT) is a rare, locally aggressive neoplasm that occurs in the synovium of joints, bursae, or tendon sheaths. TGCT is caused by upregulation of the colony-stimulating factor 1 (CSF1) gene, resulting in aberrant CSF1 expression and the recruitment of CSF1 receptor (R)-dependent inflammatory cells. Resection is the primary treatment, but nonsurgical treatment options are necessary for patients with symptomatic TGCT not amenable to surgical resection. Vimseltinib is an oral switch control TKI specifically designed to selectively and potently inhibit CSF1R. In a Phase 1/2 study in patients with TGCT, vimseltinib showed encouraging antitumor activity with an overall objective response rate (ORR) of 42% in the cohort receiving 30 mg twice weekly (recommended phase 2 dose; Gelderblom et al, ESMO 2021 Poster). Vimseltinib was also well tolerated, and the majority of the common (≥15%) treatment-emergent adverse events (TEAEs) were Grades 1–2. Among these common TEAEs, the only Grade 3–4 event in the Phase 2, twice-weekly, 30-mg cohort was increased blood creatine phosphokinase (CPK); however, this elevated CPK was not associated with any symptoms (Gelderblom et al, ESMO 2021 Poster). Phase 1/2 efficacy and safety data support further development of vimseltinib; here, we describe the ongoing Phase 3 study for patients with TGCT not amenable to surgical resection. Methods: MOTION (NCT05059262) is a Phase 3, randomized, placebo-controlled, double-blind study that aims to evaluate the efficacy and safety of vimseltinib for the treatment of TGCT not amenable to surgical resection. Participants must be at least 18 years of age and have histologically confirmed and symptomatic TGCT for which surgical resection will potentially cause worsening functional limitation or severe morbidity. Prior CSF1R therapy is not permitted (previous imatinib and nilotinib is allowed). In Part 1 of the study, eligible participants will be randomized 2:1 to receive either vimseltinib 30 mg twice a week or matched placebo for 24 weeks. The primary outcome measure is ORR assessed by central read using Response Evaluation Criteria in Solid Tumors version 1.1 at 25 weeks. Secondary outcome measures include ORR per tumor volume score, range of motion, and patient-reported outcomes. Participants assigned to placebo in Part 1 will have the option to receive vimseltinib in Part 2, a long-term treatment phase in which participants will receive open-label vimseltinib. This international study plans to randomize 120 participants and is currently enrolling. Clinical trial information: NCT05059262.

Enhancer RNA Transcription Is Essential for a Novel CSF1 Enhancer in Triple-Negative Breast Cancer.

Simple SummaryIn cancer, regulatory regions of the genome are hijacked by the tumor cells for the activation of oncogenes that lead to cancer initiation and progression. One of the most salient regulatory elements of the genome are called enhancers, which are characterized by their ability to increase the expression of their target genes. In this study, we identified a novel enhancer that drives the expression of the oncogene CSF1 in triple-negative breast cancer patients, the most aggressive subtype of breast cancer. We demonstrate that this enhancer is specifically active in triple-negative breast cancer patients compared to other breast cancer subtypes and show that its target genes portend a worse clinical outcome in patients. We then use innovative CRISPR-based genome engineering techniques to systematically perturb various features of this enhancer to elucidate its mechanisms of action and determine the consequences on tumor cell growth. Furthermore, we test our model for CSF1 enhancer function in ovarian cancer cells and demonstrate that our findings can apply to other cancer types. These results demonstrate the significant impact of enhancers in cancer biology and highlight their potential as tractable targets for therapeutic intervention.Enhancers are critical regulatory elements in the genome that help orchestrate spatiotemporal patterns of gene expression during development and normal physiology. In cancer, enhancers are often rewired by various genetic and epigenetic mechanisms for the activation of oncogenes that lead to initiation and progression. A key feature of active enhancers is the production of non-coding RNA molecules called enhancer RNAs, whose functions remain unknown but can be used to specify active enhancers de novo. Using a combination of eRNA transcription and chromatin modifications, we have identified a novel enhancer located 30 kb upstream of Colony Stimulating Factor 1 (CSF1). Notably, CSF1 is implicated in the progression of breast cancer, is overexpressed in triple-negative breast cancer (TNBC) cell lines, and its enhancer is primarily active in TNBC patient tumors. Genomic deletion of the enhancer (via CRISPR/Cas9) enabled us to validate this regulatory element as a bona fide enhancer of CSF1 and subsequent cell-based assays revealed profound effects on cancer cell proliferation, colony formation, and migration. Epigenetic silencing of the enhancer via CRISPR-interference assays (dCas9-KRAB) coupled to RNA-sequencing, enabled unbiased identification of additional target genes, such as RSAD2, that are predictive of clinical outcome. Additionally, we repurposed the RNA-guided RNA-targeting CRISPR-Cas13 machinery to specifically degrade the eRNAs transcripts produced at this enhancer to determine the consequences on CSF1 mRNA expression, suggesting a post-transcriptional role for these non-coding transcripts. Finally, we test our eRNA-dependent model of CSF1 enhancer function and demonstrate that our results are extensible to other forms of cancer. Collectively, this work describes a novel enhancer that is active in the TNBC subtype, which is associated with cellular growth, and requires eRNA transcripts for proper enhancer function. These results demonstrate the significant impact of enhancers in cancer biology and highlight their potential as tractable targets for therapeutic intervention.

A Pan-cancer Analysis Reveals the Abnormal Expression and Drug Sensitivity of CSF1.

Colony-stimulating factor-1 (CSF1) is a cytokine that is closely related to normal organ growth and development as well as tumor progression. We aimed to summarize and clarify the reasons for the abnormal expression of CSF1 in tumors and explore the role of CSF1 in tumor progression. Furthermore, drug response analysis could provide a reference for clinical medication. The expression of CSF1 was analyzed by TCGA and CCLE. Besides, cBioPortal and MethSurv databases were used to conduct mutation and DNA methylation analyses. Further, correlations between CSF1 expression and tumor stage, survival, immune infiltration, drug sensitivity and enrichment analyses were validated via UALCAN, Kaplan-Meier plotter, TIMER, CTRP and Coexperia databases. CSF1 is expressed in a variety of tissues; meaningfully, it can be detected in the blood. Compared with normal tissues, CSF1 expression was significantly decreased in most tumors. The missense mutation and DNA methylation of CSF1 might cause the downregulated expression. Moreover, decreased CSF1 expression was related to higher tumor stage and worse survival. Further, the promoter DNA methylation level of CSF1 was prognostically significant in most tumors. Besides, CSF1 was closely related to immune infiltration, especially macrophages. Importantly, CSF1 expression was associated with a good response to VEGFRs inhibitors, which may be due to the possible involvement of CSF1 in tumor angiogenesis and metastasis processes. The abnormal expression of CSF1 could serve as a promising biomarker of tumor progression and prognosis in pan-cancer. Significantly, angiogenesis and metastasis inhibitors may show a good response to CSF1-related tumors.

MEK1/2 inhibition transiently alters the tumor immune microenvironment to enhance immunotherapy efficacy against head and neck cancer

BackgroundAlthough the mitogen-activated protein kinases (MAPK) pathway is hyperactive in head and neck cancer (HNC), inhibition of MEK1/2 in HNC patients has not shown clinically meaningful activity. Therefore, we aimed...

Gingival crevicular fluid CSF-1 and IL-34 levels in patients with stage III grade C periodontitis and uncontrolled type 2 diabetes mellitus.

Periodontal diseases are inflammatory conditions that alter the host's response to microbial pathogens. Type 2 diabetes mellitus (T2DM) is a complex disease that affects the incidence and severity of periodontal diseases. This study investigated the gingival crevicular fluid (GCF) levels of colony-stimulating factor-1 (CSF-1) and interleukin-34 (IL-34) in patients with stage III grade C periodontitis (SIII-GC-P) and stage III grade C periodontitis with uncontrolled type 2 diabetes (SIII-GC-PD). In total, 72 individuals, including 24 periodontally healthy (PH), 24 SIII-GC-P, and 24 SIII-GC-PD patients, were recruited for this study. Periodontitis patients (stage III) had interdental attachment loss (AL) of 5 mm or more, probing depth (PD) of 6 mm or more, radiographic bone loss advancing to the middle or apical part of the root, and tooth loss (<5) due to periodontal disease. Radiographic bone loss in the teeth was also evaluated; grade C periodontitis was defined as a ratio of the percentage of root bone loss to age greater than 1.0. The plaque index (PI), gingival index (GI), presence of bleeding on probing (BOP), PD, and clinical AL were used for clinical periodontal assessments. GCF samples were obtained and analyzed using an enzyme-linked immunosorbent assay. All clinical parameters-PD, AL, GI, BOP, and PI-were significantly higher in the SIII-GC-PD group than in the PH and SIII-GC-P groups for both the full mouth and each sampling site (P<0.05). The total IL-34 and CSF-1 levels were significantly higher in the SIII-GC-PD group than in the PH and SIII-GC-P groups (P<0.05), and there were significant differences between the periodontitis groups (P<0.05). These findings suggest that IL-34 and CSF-1 expression increases in patients with SIII-GC-PD. CSF-1 was associated with the inflammatory status of periodontal tissues and T2DM, while IL-34 was associated only with T2DM. ClinicalTrials.gov Identifier: NCT04891627.

Neoplastic synovial lining cells that coexpress podoplanin and CD90 overproduce CSF-1, driving tenosynovial giant cell tumor.

Tenosynovial giant cell tumor (TCGT) is a rare neoplasm affecting the synovium of joints, bursae, and tendon sheaths. The overproduction of colony-stimulating factor-1 (CSF-1) by a minority of the tumor population works in a paracrine fashion to drive tumor growth. Pathology of the reactive, monocytic component has been well elucidated, whereas the populations of neoplastic cells and all the sources of CSF-1 overproduction are incompletely characterized. Podoplanin (PDPN), or gp38, is a cell surface glycoprotein that is expressed on fibroblast-like synovial cells and upregulated in rheumatoid arthritis and many cancers; it governs cell mobility, epithelial-mesenchymal transition, and other functions and is associated with lymphangiogenesis and poor prognosis in many solid tumors, which underscores its local and possible systemic effects. We found higher PDPN expression in TGCT than in internal controls of patients' healthy synovium. Flow cytometry partitioned PDPNhigh cells into PDPNhigh CD90+ and PDPNhigh CD14+ populations. Quantitative real-time polymerase chain reaction analysis of the PDPNhigh CD90+ cells revealed that CSF-1 expression was 10-fold higher than in PDPNhigh CD14+ cells. Therefore, we conclude that the lining fibroblast-like synovial cells, which express PDPNhigh CD90+ , are responsible for the overproduction of CSF-1 and for driving tumor growth.

Long non-coding RNA HOMER3-AS1 drives hepatocellular carcinoma progression via modulating the behaviors of both tumor cells and macrophages

The crosstalk between cancer cells and tumor microenvironment plays critical roles in hepatocellular carcinoma (HCC). The identification of long non-coding RNAs (lncRNAs) mediating the crosstalk might promote the development of new therapeutic strategies against HCC. Here, we identified a lncRNA, HOMER3-AS1, which is over-expressed in HCC and correlated with poor survival of HCC patients. HOMER3-AS1 promoted HCC cellular proliferation, migration, and invasion, and reduced HCC cellular apoptosis. Furthermore, HOMER3-AS1 promoted macrophages recruitment and M2-like polarization. In vivo, HOMER3-AS1 significantly facilitated HCC progression. Mechanism investigations revealed that HOMER3-AS1 activated Wnt/β-catenin signaling via upregulating HOMER3. Functional rescue experiments revealed that HOMER3/Wnt/β-catenin axis mediated the roles of HOMER3-AS1 in promoting HCC cellular malignant phenotypes. Furthermore, colony stimulating factor-1 (CSF-1) was also identified as a critical downstream target of HOMER3-AS1. HOMER3-AS1 increased CSF-1 expression and secretion. Blocking CSF-1 reversed the roles of HOMER3-AS1 in inducing macrophages recruitment and M2 polarization. Furthermore, positive correlations between HOMER3-AS1 and HOMER3 expression, HOMER3-AS1 and CSF-1 expression, and HOMER3-AS1 expression and M2-like macrophages infiltration were found in human HCC tissues. In summary, our findings demonstrated that HOMER3-AS1 drives HCC progression via modulating the behaviors of both tumor cells and macrophages, which are dependent on the activation of HOMER3/Wnt/β-catenin axis and CSF-1, respectively. HOMER3-AS1 might be a promising prognostic and therapeutic target for HCC.