Vascular channel formation by human melanoma cells in vivo and in vitro: vasculogenic mimicry

Dihydroartemisinin inhibited vasculogenic mimicry in gastric cancer through the FGF2/FGFR1 signaling pathway

Vasculogenic mimicry (VM) is a novel model for supplying blood to multiple tumors, including gastric cancer (GC), and is a potential target for its treatment. Dihydroartemisinin (DHA) is a potential natural antitumor substance that inhibits the progression of tumors in many ways. The research aimed to evaluate the impact of DHA on VM formation and its mechanisms. The IC50 of DHA, DHA's effect on proliferation, invasion, and migration in GC cells and VM formation in both cell and animal models were determined through wound healing, MTT, EdU, colony formation, and Transwell assays. Genomics was employed to identify genes related to DHA inhibition of VM formation, and to analyze their relationship to VM formation. qRT‒PCR and western blot (WB) analysis were carried out to analyze the changes in protein and mRNA levels after DHA treatment and the changes in VM-associated protein biomarkers after blocking target gene-related pathways. The mechanism by which DHA inhibits VM in GC was elucidated in vivo. DHA reduced the invasion, proliferation, and migration of GC cells and inhibited VM in cells and in vivo. A total of 220 DEGs were identified in the DHA-treated HGC-27 cells. Among the 146 downregulated genes, fibroblast growth Factor 2 (FGF2) was most closely associated with angiogenesis and VM. The level of FGF2 in GC tissues with VM was markedly greater than in VM lacking tissues. Treatment with DHA or FGFR1 blockade suppressed VM formation and reduced VM-related biomarker proteins. DHA suppressed tumor progression and VM formation by reducing FGF2 in xenograft mouse models. Per our knowledge, this is the first study to demonstrate the inhibitory effect of DHA on VM, providing a novel strategy for the treatment of GC.

BCAR1 facilitates the survival of lung adenocarcinoma cells by augmenting the unfolded protein response, autophagy, and the formation of vasculogenic mimicry

BACKGROUND

Our objective was to elucidate the pivotal roles of BCAR1 in unfolded protein response (UPR), autophagy and vasculogenic mimicry (VM) formation, processes that essential for the metastasis of lung adenocarcinoma (LUAD) cells.

METHODS

The morphological assessment of endoplasmic reticulum (ER) status and autolysosomes in H1975 and H1299 LUAD cells following BCAR1 knockout (KO) was conducted using transmission electron microscope. The expression of markers and cellular functions related to the UPR, autophagy, and VM formation were examined in LUAD cells tissues. Additionally, proteomic analysis of LUAD cells was performed via mass spectrometry, and the pertinent signaling pathways were analyzed using bioinformatics tools.

RESULTS

BCAR1-KO inhibited autophagy and UPR induced triggered starvation in LUAD cells. Cleaved-ATF6a-mediated UPR and subsequent autophagy, enhanced by BCAR1, were confirmed using the UPR stimulator and blocker. High BCAR1 expression, along with elevated UPR and autophagy, predicts poor prognosis in LUAD patients. BCAR1-KO reduced tube formation and VM markers expressions in LUAD cells. Additionally, BCAR1 expression positively correlated with VM formation in BALB/c-nu mice xenografts and LUAD patient tissues.

CONCLUSION

BCAR1 promotes LUAD metastasis by enhancing cancer cell survival in nutrient-poor environments through ATF6-mediated UPR activation and autophagy. As BCAR1 induces VM formation, metastatic lesions eventually colonize. Thus, BCAR1 is a promising anti-metastasis target.

Splicing dysregulation in glioblastoma alters the function of cell migration-related genes

Glioblastoma (GBM) has a poor prognosis with a high recurrence and low survival rate. Previous RNA-seq analyses have revealed that alternative splicing (AS) plays a role in GBM progression. Here, we present a novel AS analysis method (Semi-Q) and describe its use to identify GBM-specific AS events. We analyzed RNA-seq data from normal brain (NB), normal human astrocytes (NHAs) and GBM samples, and found that comparison between NHA and GBM was especially informative. Importantly, this analysis revealed that genes encoding cell migration-related proteins, including filamins (FLNs) and actinins (ACTNs), were among those most affected by differential AS. Functional assays revealed that dysregulated AS of FLNA, B and C transcripts produced protein isoforms that not only altered transcription of cell proliferation-related genes but also led to enhanced cell migration, resistance to cell death and/or mitochondrial respiratory function, while a dysregulated AS isoform of ACTN4 enhanced cell migration. Together, our results indicate that cell migration and actin cytoskeleton-related genes are differentially regulated by AS in GBM, supporting a role for AS in facilitating tumor growth and invasiveness.

Emerging Paradigms in Cancer Metastasis: Ghost Mitochondria, Vasculogenic Mimicry, and Polyploid Giant Cancer Cells

The capacity of cancer cells to migrate from a primary tumor, disseminate throughout the body, and eventually establish secondary tumors is a fundamental aspect of metastasis. A detailed understanding of the cellular and molecular mechanisms underpinning this multifaceted process would facilitate the rational development of therapies aimed at treating metastatic disease. Although various hypotheses and models have been proposed, no single concept fully explains the mechanism of metastasis or integrates all observations and experimental findings. Recent advancements in metastasis research have refined existing theories and introduced new ones. This review evaluates several novel/emerging theories, focusing on ghost mitochondria (GM), vasculogenic mimicry (VM), and polyploid giant cancer cells (PGCCs).

Novel deoxyhypusine synthase (DHPS) inhibitors target hypusination-induced vasculogenic mimicry (VM) against malignant melanoma

Vasculogenic mimicry (VM) contributes factor to the poor prognosis of malignant melanoma. Developing deoxyhypusine synthase (DHPS) inhibitors against melanoma VM is clinically essential. In this study, we optimized and synthesized a series of compounds based on the candidate structure, and the hit compound 7k was identified through enzyme assay and cell viability inhibition screening. Both inside and outside the cell, 7k's ability to target DHPS and its high affinity were demonstrated. Molecular dynamics and point mutation indicated that mutations of K329 or V129 in DHPS abolish 7k's inhibitory activity. Using PCR arrays, solid-state antibody microarrays, and angiogenesis assays investigated 7k's impact on melanoma cells to reveal that DHPS regulates melanoma VM by promoting FGFR2 and c-KIT expression. Surprisingly, 7k was discovered to inhibit MC1R-mediated melanin synthesis in the zebrafish. Pharmacokinetic evaluations demonstrated 7k's favorable properties, and xenograft models evidenced its notable anti-melanoma efficacy, achieving a TGI of 73 %. These results highlighted DHPS as key in melanoma VM formation and confirmed 7k's potential as a novel anti-melanoma agent.

Characterization of cell states in biliary tract cancers identifies mechanisms of therapeutic resistance in a phase II trial of DKN-01/nivolumab

Biliary tract cancers demonstrate profound therapeutic resistance, and broadly effective therapies for refractory disease are lacking. We conducted a single-arm, second-line phase II trial combining DKN-01, a humanized monoclonal antibody targeting Dickkopf-1 (DKK-1), and nivolumab to treat patients with advanced biliary tract cancer (NCT04057365). No objective responses were seen. To identify mechanisms of treatment failure, we analyzed paired pre-treatment and on-treatment biopsies using scRNA-seq and constructed a detailed molecular classification of malignant and immune cells. We annotated five biliary tract cancer malignant cell states: classical, basal, mesenchymal, neural-like, and endothelial-like. Neural-like and endothelial-like states, which drive therapeutic resistance in other cancers, have not previously been described in BTC. Malignant cell states co-varied with distinct immune cell states, revealing diverse mechanisms of myeloid and T-cell mediated immune suppression, including M2 myeloid and terminally exhausted T cell programs that were induced by DKN-01/nivolumab. Here, we provide the first systematic classification of functionally annotated cell states in biliary tract cancer and provide new insight into resistance mechanisms to an immunotherapy combination that can inform the next generation of trials.

Accessing the vasculature in cancer: revising an old hallmark

The classic cancer hallmark, inducing angiogenesis, was born out of the long-held notion that tumours could grow only if new vessels were formed. The attempts, based on this premise, to therapeutically restrain angiogenesis in hopes of controlling tumour growth have been less effective than expected. This is partly because primary and metastatic tumours can grow without angiogenesis. The discovery of nonangiogenic cancers and the mechanisms they use to exploit normal vessels, called 'vessel co-option,' has opened a new field in cancer biology. Consequently, the cancer hallmark, 'inducing angiogenesis,' has been modified to 'inducing or accessing vasculature.'

Interference of FZD2 suppresses proliferation, vasculogenic mimicry and stemness in glioma cells via blocking the Notch/NF‑κB signaling pathway

Frizzled family protein 2 (FZD2) is widely associated with tumor development and metastasis. The present study aimed to gain an insight into the role and regulatory mechanism of FZD2 in glioma. The expression level of FZD2 in normal astrocyte and glioma cells was determined by reverse transcription-quantitative PCR and western blotting, and cell transfection was conducted for FZD2 expression knockdown. Malignant behaviors including cell proliferation, migration and invasion, vasculogenic mimicry (VM) and cell stemness were determined using Cell Counting Kit-8, 5-Ethynyl-2'-deoxyuridine (EdU) staining, colony formation, wound healing, Transwell, 3D culturing and sphere formation assays. The expression levels of proteins related to stemness, epithelial-mesenchymal transition (EMT) and Notch/NF-κB signaling were measured by western blotting. Then, the Notch agonist, Jagged-1 (JAG), was adopted for rescue experiments. The results demonstrated that FZD2 was highly expressed in glioma cells. Interference of FZD2 expression suppressed the proliferation of glioma cells, as evidenced by the reduced cell viability and the number of EdU+ cells and colonies. Meanwhile, the reduced sphere formation ability and decreased protein expression of Nanog, Sox2 and Oct4 following FZD2 knockdown confirmed that FZD2 repressed cell stemness in glioma. Additionally, FZD2 knockdown suppressed the migration, invasion, EMT and VM formation capabilities of glioma cells, and also blocked the Notch/NF-κB signaling pathway. Furthermore, activation of Notch by JAG treatment partially reversed the aforementioned FZD2 knockdown-mediated changes in glioma cell malignant behaviors. In conclusion, FZD2 may contribute to glioma progression through activating the Notch/NF-κB signaling pathway, providing a plausible therapeutic target for the treatment of glioma.

Nrf2/ASPM axis regulated vasculogenic mimicry formation in hepatocellular carcinoma under hypoxia

BACKGROUND

Hypoxic microenvironment is a common feature of most solid tumors including hepatocellular carcinoma (HCC). Vasculogenic mimicry (VM) formation by tumor cells could provide blood supply to tumor cells under hypoxia. NFE2 like basic leucine zipper (bZIP) transcription factor 2 (Nrf2), a regulator of cellular homeostasis, may promote tumor progression in the hypoxic conditions. However, the role and regulatory mechanisms of Nrf2 in HCC are not fully elucidated.

METHODS

Nrf2 and assembly factor for spindle microtubules (ASPM) expression modulations were conducted by lentiviral transfections. Western blot, immunofluorescence, ChIP-qPCR, dual-luciferase reporter gene assay, flow cytometry, RNA sequencing, multiple bioinformatics databases analysis, cell function assays in vitro, mouse model in vivo and human HCC tissues were employed to assess the effect of Nrf2/ASPM axis on HCC progression under hypoxia.

RESULTS

Nrf2 and ASPM expression facilitated epithelial-mesenchymal transition (EMT), cancer stem cells (CSCs) feature, and VM formation of HCC cells under hypoxia. Furthermore, Nrf2-regulated ASPM expression, via binding directly to the promoter region of ASPM and transcriptionally promoting ASPM expression. ASPM re-expression in Nrf2 knockdown cells or ASPM knockdown in Nrf2 overexpression cells reversed the cellular function caused by Nrf2. Meantime, retinol metabolism pathway was disrupted following abnormal ASPM expression. Nrf2/ASPM axis in murine models accelerated tumor growth and VM, corroborating in vitro findings. All-trans retinoic acid treatment reversed stemness and VM of HCC cells in vitro and in vivo. Clinically, Nrf2 and ASPM expressions were related to poor prognosis of HCC patients.

CONCLUSIONS

Nrf2 drives EMT, CSCs characteristics and VM in HCC under hypoxia through the modulation of ASPM. Retinol metabolism pathway was dysregulated in HCC cells with ASPM overexpression. Nrf2/ASPM axis and related pathway provided potential therapeutic target for HCC.

The anti-angiogenic and anti-vasculogenic mimicry effects of GN25 in endothelial and glioma cells

BACKGROUND AND PURPOSE

Scientists have been exploring anti-angiogenic strategies to inhibit angiogenesis and prevent tumor growth. Vasculogenic mimicry (VM) in glioblastoma multiforme (GBM) poses a challenge, complicating anti-angiogenesis therapy. A novel drug, GN25 (3-[{1,4-dihydro-5,8-dimethoxy-1,4-dioxo-2-naphthalenyl}thio]-propanoic acid), can inhibit tumor formation. This study aims to investigate the microenvironmental effects and molecular mechanisms of GN25 in anti-angiogenesis and anti-VM.

EXPERIMENTAL APPROACH

MTT (3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide) assay was used to evaluate the cell viability of different concentrations of GN25 in human umbilical vein endothelial cells (HUVEC) and Uppsala 87 malignant glioma (U87MG) cells. Functional assays were used to investigate the effects of GN25 on angiogenesis-related processes, whereas gelatin zymography, enzyme-linked immunosorbent assays, and Western blotting were utilized to assess the influence on matrix metalloproteinase (MMP)-2 and vascular endothelial growth factor (VEGF) secretion and related signaling pathways.

KEY RESULTS

GN25 suppressed migration, wound healing, and tube formation in HUVECs and disrupted angiogenesis in a rat aorta ring and zebrafish embryo model. GN25 dose-dependently reduced phosphatidylinositol 3-kinase/AKT and inhibited MMP-2/VEGF secretion in HUVECs. In U87MG cells, GN25 inhibited migration, wound healing, and VM, accompanied by a decrease in MMP-2 and VEGF secretion. The results indicate that GN25 effectively inhibits angiogenesis and VM formation in HUVECs and U87MG cells without affecting preexisting vascular structures.

CONCLUSION AND IMPLICATIONS

This study elaborated GN25's potential as an anti-angiogenic agent by elucidating its inhibitory effects on classical angiogenesis. VM provides valuable insights for developing novel therapeutic strategies against tumor progression and angiogenesis-related diseases. These results indicate the potential of GN25 as a promising candidate for angiogenesis-related diseases.

Review of METTL3 in colorectal cancer: From mechanisms to the therapeutic potential

N6-methyladenosine (m6A), the most abundant modification in mRNAs, affects the fate of the modified RNAs at the post-transcriptional level and participants in various biological and pathological processes. Increasing evidence shows that m6A modification plays a role in the progression of many malignancies, including colorectal cancer (CRC). As the only catalytic subunit in methyltransferase complex, methyltransferase-like 3 (METTL3) is essential to the performance of m6A modification. It has been found that METTL3 is associated with the prognosis of CRC and significantly influences various aspects of CRC, such as cell proliferation, invasion, migration, metastasis, metabolism, tumor microcirculation, tumor microenvironment, and drug resistance. The relationship between METTL3 and gut-microbiota is also involved into the progression of CRC. Furthermore, METTL3 might be a viable target for CRC treatment to prolong survival. In this review, we comprehensively summarize the function of METTL3 in CRC and the underlying molecular mechanisms. We aim to deepen understanding and offer new ideas for diagnostic biomarkers and therapeutic targets for colorectal cancer.

Aberrant overexpression of myosin 1b in glioblastoma promotes angiogenesis via VEGF-myc-myosin 1b-Piezo1 axis

Glioblastoma (GBM) is the most aggressive intracranial malignancy with poor prognosis. Enhanced angiogenesis is an essential hallmark of GBM, which demonstrates extensive microvascular proliferation and abnormal vasculature. Here, we uncovered the key role of myosin 1b in angiogenesis and vascular abnormality in GBM. Myosin 1b is upregulated in GBM endothelial cells (ECs) compared to the paired nonmalignant brain tissue. In our study, we found that myosin 1b promotes migration, proliferation, and angiogenesis of human/mouse brain ECs. We also found that myosin 1b expression in ECs can be regulated by vascular endothelial growth factor (VEGF) signaling through myc. Moreover, myosin 1b promotes angiogenesis via Piezo1 by enhancing Ca2+ influx, in which process VEGF can be the trigger. In conclusion, our results identified myosin 1b as a key mediator in promoting angiogenesis via mechanosensitive ion channel component 1 (Piezo1) and suggested that VEGF/myc signaling pathway could be responsible for driving the changes of myosin 1b overexpression in GBM ECs.

The role of Rhizoma Paridis saponins on anti-cancer: The potential mechanism and molecular targets

Cancer is a disease characterized by uncontrolled cell proliferation, leading to excessive growth and invasion that can spread to other parts of the body. Traditional Chinese medicine has made new advancements in the treatment of cancer, providing new perspectives and directions for cancer treatment. Rhizoma Paridis is a widely used Chinese herbal medicine with documented anti-cancer effects dating back to ancient times. Modern research has shown that Rhizoma Paridis saponins (RPS) have various pharmacological activities. RPS can inhibit cancer in multiple ways, such as suppressing tumor growth, inducing cell cycle arrest, promoting cell apoptosis, enhancing cell autophagy, inducing ferroptosis, reducing inflammation, inhibiting angiogenesis, as well as inhibiting metastasis and invasion, and these findings demonstrate the potent anti-cancer activity of RPS. Polyphyllin I, polyphyllin II, polyphyllin VI, and polyphyllin VII have been widely reported as the main active ingredients with anti-cancer properties. Polyphyllin D, polyphyllin E, and polyphyllin G have also been confirmed to possess strong anti-cancer activity in recent years. Therefore, this review dives deep into the molecular mechanisms underlying the anti-cancer effects of RPS to serve as a valuable reference for future scientific research and their potential applications in cancer treatment.

Identification of new subtypes of breast cancer based on vasculogenic mimicry related genes and a new model for predicting the prognosis of breast cancer

Breast cancer is a malignant tumor that poses a serious threat to women's health, and vasculogenic mimicry (VM) is strongly associated with bad prognosis in breast cancer. However, the relationship between VM and immune infiltration in breast cancer and the underlying mechanisms have not been fully studied. On the basis of the Cancer Genome Atlas (TCGA), Fudan University Shanghai Cancer Center (FUSCC) database, GSCALite database, and gene set enrichment analysis (GSEA) datasets, we investigated the potential involvement of VM-related genes in the development and progression of breast cancer. We analyzed the differential expression, mutation status, methylation status, drug sensitivity, tumor mutation burden (TMB), microsatellite instability (MSI), immune checkpoints, tumor microenvironment (TME), and immune cell infiltration levels associated with VM-related genes in breast cancer. We created two VM subclusters out of breast cancer patients using consensus clustering, and discovered that patients in Cluster 1 had better survival outcomes compared to those in Cluster 2. The infiltration levels of T cells CD4 memory resting and T cells CD8 were higher in Cluster 1, indicating an immune-active state in this cluster. Additionally, we selected three prognostic genes (LAMC2, PIK3CA, and TFPI2) using Lasso, univariate, and multivariate Cox regression and constructed a risk model, which was validated in an external dataset. The prognosis of patients is strongly correlated with aberrant expression of VM-related genes, which advances our knowledge of the tumor immune milieu and enables us to identify previously unidentified breast cancer subtypes. This could direct more potent immunotherapy approaches.

In vitro biomaterial priming of human mesenchymal stromal/stem cells : implication of the Src/JAK/STAT3 pathway in vasculogenic mimicry

Mesenchymal stromal/stem cells (MSC) play a crucial role in promoting neovascularization, which is essential for wound healing. They are commonly utilized as an autologous source of progenitor cells in various stem cell-based therapies. However, incomplete MSC differentiation towards a vascular endothelial cell phenotype questions their involvement in an alternative process to angiogenesis, namely vasculogenic mimicry (VM), and the signal transducing events that regulate their in vitro priming into capillary-like structures. Here, human MSC were primed on top of Cultrex matrix to recapitulate an in vitro phenotype of VM. Total RNA was extracted, and differential gene expression assessed through RNA-Seq analysis and RT-qPCR. Transient gene silencing was achieved using specific siRNA. AG490, Tofacitinib, and PP2 pharmacological effects on VM structures were analyzed using the Wimasis software. In vitro VM occurred within 4 h and was prevented by the JAK/STAT3 inhibitors AG490 and Tofacitinib, as well as by the Src inhibitor PP2. RNA-Seq highlighted STAT3 as a signaling hub contributing to VM when transcripts from capillary-like structures were compared to those from cell monolayers. Concomitant increases in IL6, IL1b, CSF1, CSF2, STAT3, FOXC2, RPSA, FN1, and SNAI1 transcript levels suggest the acquisition of a combined angiogenic, inflammatory and epithelial-to-mesenchymal transition phenotype in VM cultures. Increases in STAT3, FOXC2, RPSA, Fibronectin, and Snail protein expression were confirmed during VM. STAT3 and RPSA gene silencing abrogated in vitro VM. In conclusion, in vitro priming of MSC into VM structures requires Src/JAK/STAT3 signaling. This molecular evidence indicates that a clinically viable MSC-mediated pseudo-vasculature process could temporarily support grafts through VM, allowing time for the host vasculature to infiltrate and remodel the injured tissues.

Spheroid-Hydrogel-Integrated Biomimetic System: A New Frontier in Advanced Three-Dimensional Cell Culture Technology

BACKGROUND

Despite significant advances in three-dimensional (3D) cell culture technologies, creating accurate in vitro models that faithfully recapitulate complex in vivo environments remains a major challenge in biomedical research. Traditional culture methods often fail to simultaneously facilitate critical cell-cell and cell-extracellular matrix (ECM) interactions while providing control over mechanical and biochemical properties.

SUMMARY

This review introduces the spheroid-hydrogel-integrated biomimetic system (SHIBS), a groundbreaking approach that synergistically combines spheroid culture with tailored hydrogel technologies. SHIBS uniquely bridges the gap between traditional culture methods and physiological conditions by offering unprecedented control over both cellular interactions and environmental properties. We explore how SHIBS is revolutionizing fields ranging from drug discovery and disease modeling to regenerative medicine and basic biological research. The review discusses current challenges in SHIBS technology, including reproducibility, scalability, and high-resolution imaging, and outlines ongoing research addressing these issues. Furthermore, we envision the future evolution of SHIBS into more sophisticated organoid-hydrogel-integrated biomimetic systems and its integration with cutting-edge technologies such as microfluidics, 3D bioprinting, and artificial intelligence.

KEY MESSAGES

SHIBS represents a paradigm shift in 3D cell culture technology, offering a unique solution to recreate complex in vivo environments. Its potential to accelerate the development of personalized therapies across various biomedical fields is significant. While challenges persist, the ongoing advancements in SHIBS technology promise to overcome current limitations, paving the way for more accurate and reliable in vitro models. The future integration of SHIBS with emerging technologies may revolutionize biomimetic modeling, potentially reducing the need for animal testing and expediting drug discovery processes. This comprehensive review provides researchers and clinicians with a holistic understanding of SHIBS technology, its current capabilities, and its future prospects in advancing biomedical research and therapeutic innovations.

Vasculogenic mimicry triggers early recidivation and resistance to adjuvant therapy in esophageal cancer

OBJECTIVE

To investigate the impact of vasculogenic mimicry (VM) and postoperative adjuvant therapy on the prognosis and survival of patients with esophageal squamous cell carcinoma (ESCC), as well as to assess whether VM affects the clinical benefit of postoperative adjuvant therapy.

METHODS

This single-center retrospective analysis included patients who underwent radical surgery for ESCC, which was documented in the medical record system. The presence or absence of VM in surgical specimens was determined using double staining with PAS/CD31. Stratification was applied based on adjuvant therapy and VM status. Survival curves and COX modeling were used to analyze the impact of the presence or absence of VM on the benefit of adjuvant therapy and the survival prognosis of patients.

RESULTS

VM-positive patients were more prone to postoperative recurrence and metastasis. VM was identified as an independent risk factor for progression-free survival (PFS) (p < 0.001, 95% CI:1.809-3.852) and overall survival (OS) (p < 0.001, 95% CI:1.603-2.786) in postoperative ESCC. Postoperative adjuvant therapy significantly prolonged PFS (p = 0.008) and OS time (p < 0.001) in patients with stage II and III ESCC, with concurrent chemoradiotherapy being the most effective. However, the presence of VM significantly reduced the benefits of postoperative adjuvant therapy (p < 0.001).

CONCLUSION

VM negatively impacts the prognosis of postoperative ESCC patients and reduces the efficacy of postoperative adjuvant therapy.

Hsa_circ_0000520 suppresses vasculogenic mimicry formation and metastasis in bladder cancer through Lin28a/PTEN/PI3K signaling

BACKGROUND

Vasculogenic mimicry (VM) is a potential cause of resistance to antiangiogenic therapy and is closely related to the malignant progression of tumors. It has been shown that noncoding RNAs play an important role in the formation of VM in malignant tumors. However, the role of circRNAs in VM of bladder cancer and the regulatory mechanisms are unclear.

METHODS

Firstly, hsa_circ_0000520 was identified to have circular character by Sanger sequencing and Rnase R assays. Secondly, the potential clinical value of hsa_circ_0000520 was explored by quantitative real-time polymerase chain reaction (qRT-PCR) and fluorescence in situ hybridization (FISH) of clinical specimens. Thirdly, the role of hsa_circ_0000520 in bladder cancer invasion, migration, and VM formation was examined by in vivo and in vitro experiments. Finally, the regulatory mechanisms of hsa_circ_0000520 in the malignant progression of bladder cancer were elucidated by RNA binding protein immunoprecipitation (RIP), RNA pulldown, co-immunoprecipitation (co-IP), qRT-PCR, Western blot (WB), and fluorescence co-localization.

RESULTS

Hsa_circ_0000520 was characterized as a circular RNA and was lowly expressed in bladder cancer compared with the paracancer. Bladder cancer patients with high expression of hsa_circ_0000520 had better survival prognosis. Functionally, hsa_circ_0000520 inhibited bladder cancer invasion, migration, and VM formation. Mechanistically, hsa_circ_0000520 acted as a scaffold to promote binding of UBE2V1/UBC13 to Lin28a, further promoting the ubiquitous degradation of Lin28a, improving PTEN mRNA stability, and inhibiting the phosphorylation of the PI3K/AKT pathway. The formation of hsa_circ_0000520 in bladder cancer was regulated by RNA binding protein QKI.

CONCLUSIONS

Hsa_circ_0000520 inhibits metastasis and VM formation in bladder cancer and is a potential target for bladder cancer diagnosis and treatment.

Tumor-Derived Immunoglobulin-Like Transcript 4 Promotes Postoperative Relapse via Inducing Vasculogenic Mimicry through MAPK/ERK Signaling in Hepatocellular Carcinoma

Conventional anti-angiogenesis drugs are usually unsatisfactory in hepatocellular carcinoma (HCC) treatment. Therefore, it is urgent to find new precise therapeutic targets and to further develop more effective drugs for the treatment of HCC. Vasculogenic mimicry (VM) is different from classic endothelium-dependent angiogenesis and is associated with a poor prognosis in patients with malignant tumor. However, the mechanism underlying VM is complex and not fully defined. Ig-like transcript (ILT)-4, as a negative regulator of immune response, was recently found to be expressed in many solid tumors. However, whether and how ILT4 regulates VM remains unclear. This study found VM enriched in HCC tissues, especially in tissues from patients with relapse within 5 years after surgery. Similarly, ILT4 expression level was also higher in HCC tissues from patients with relapse within 5 years after surgery. Linear regression analysis revealed a positive correlation between the expression of ILT4 and VM density. Furthermore, Overexpression/knockdown of ILT4 expression upregulated/down-regulated VM-related marker, three-dimensional tube formation, and migration and invasion in HCC cell lines in vitro. In mechanistic studies, ILT4 promoted VM formation via MAPK/ERK signaling. This study provides a rationale and mechanism for ILT4-mediated postoperative relapse via inducing VM in HCC. The related molecular pathways can be used as novel therapeutic targets for the inhibition of HCC angiogenesis and postoperative relapse.

Hyaluronidase improves the efficacy of nab-paclitaxel after prolonged angiogenesis inhibition in preclinical models for esophagogastric cancer

BACKGROUND

Long-term anti-angiogenesis leads to pruned vasculature, densely deposited extracellular matrix (ECM), and consequently reduced chemotherapy delivery in esophagogastric cancer (EGC). To address this issue, we evaluated the efficacy of adding a hyaluronidase or a NO-donor to the regimen of chemotherapy and anti-angiogenic drugs.

METHODS

A patient-derived EGC xenograft model was developed. Grafted mice were randomly assigned to four experimental groups and one control group. The experimental groups received DC101, a murine angiogenesis inhibitor, and nab-paclitaxel (NPTX), with the addition of hyaluronidase (PEGPH20), or NO-donor (nitroglycerine, NTG), or their combination, respectively. We compared tumor growth during 17 days of treatment. We performed immunohistochemistry for ECM components hyaluronan (HA) and collagen, CD31 for endothelial cells, and γH2AX for DNA damage. The positively stained areas were quantified, and vessel diameters were measured using QuPath software.

RESULTS

Prolonged DC101 treatment induced deposition of HA (p<0.01) and collagen (p<0.01). HA was effectively degraded by PEGPH20 (p<0.001), but not by NTG as expected. Both PEGPH20 (p<0.05) and NTG (p<0.01) dilated vessels collapsed in response to long-term DC101 treatment. However, only PEGPH20 (rather than NTG) was found to significantly inhibit tumor growth (p<0.05) in combination with NPTX and DC101.

CONCLUSIONS

These findings suggest that the mechanical barrier of HA is the major reason responsible for the resistance developed during prolonged anti-angiogenesis in EGC. Incorporating PEGPH20 into the existing treatment regimen is promising to improve outcomes for patients with EGC.

The Importance of Hypoxia-Related to Hemoglobin Concentration in Breast Cancer

The importance of hemoglobin (Hgb) as a novel prognostic biomarker in predicting clinical features of cancers has been the subject of intense interest. Anemia is common in various types of cancer including breast cancer (BC) and is considered to be attributed to tumoral hypoxia. Cancer microenvironments are hypoxic compared with normal tissues, and this hypoxia is associated with Hgb concentration. Recent preclinical documents propose a direct or indirect correlation of intratumoral hypoxia, specifically along with acidity, with Hgb concentration and anemia. Analysis of the prognostic value of Hgb in BC patients has demonstrated increased hypoxia in the intratumoral environment. A great number of studies demonstrated that lower concentrations of Hgb before or during common cancer treatments, such as radiation and chemotherapy, is an essential risk factor for poor prognostic and survival, as well as low quality of life in BC patients. This data suggests a potential correlation between anemia and hypoxia in BC. While low Hgb levels are detrimental to BC invasion and survival, identification of a distinct and exact threshold for low Hgb concentration is challenging and inaccurate. The optimal thresholds for Hgb and partial pressure of oxygen (pO2) vary based on different factors including age, gender, therapeutic approaches, and tumor types. While necessitating further investigations, understanding the correlation of Hgb levels with tumoral hypoxia and oxygenation could improve exploring strategies to overcome radio-chemotherapy related anemia in BC patients. This review highlights the collective association of Hgb concentration and hypoxia condition in BC progression.

The cellular-centered view of hypoxia tumor microenvironment: Molecular mechanisms and therapeutic interventions

Cancer is a profoundly dynamic, heterogeneous and aggressive systemic ailment, with a coordinated evolution of various types of tumor niches. Hypoxia plays an indispensable role in the tumor micro-ecosystem, drastically enhancing the plasticity of cancer cells, fibroblasts and immune cells and orchestrating intercellular communication. Hypoxia-induced signals, particularly hypoxia-inducible factor-1α (HIF-1α), drive the reprogramming of genetic, transcriptional, and proteomic profiles. This leads to a spectrum of interconnected processes, including augmented survival of cancer cells, evasion of immune surveillance, metabolic reprogramming, remodeling of the extracellular matrix, and the development of resistance to conventional therapeutic modalities like radiotherapy and chemotherapy. Here, we summarize the latest research on the multifaceted effects of hypoxia, where a multitude of cellular and non-cellular elements crosstalk with each other and co-evolve in a synergistic manner. Additionally, we investigate therapeutic approaches targeting hypoxic niche, encompassing hypoxia-activated prodrugs, HIF inhibitors, nanomedicines, and combination therapies. Finally, we discuss some of the issues to be addressed and highlight the potential of emerging technologies in the treatment of cancer.

Effects of natural products on angiogenesis in melanoma

Melanoma is the most aggressive form of skin cancer and originates from genetic mutations in melanocytes. The disease is multifactorial, but its main cause is overexposure to UV radiation. Currently, available chemotherapy expresses little to no results, which may justify the extensive use of natural products to treat this cancer. In this study, we reviewed the inhibition of melanoma angiogenesis by natural products and its potential mechanisms using literature from PubMed, EMBASE, Web of Science, Ovid, ScienceDirect and China National Knowledge Infrastructure databases. According to summarizes 27 natural products including alkaloids, polyphenols, terpenoids, flavonoids, and steroids that effectively inhibit angiogenesis in melanoma. In addition to these there are 15 crude extracts that can be used as promising agents to inhibit angiogenesis, but their core components still deserve further investigation. There are current studies on melanoma angiogenesis involving oxidative stress, immune-inflammatory response, cell proliferation and migration and capillary formation. The above natural products can be involved in melanoma angiogenesis through core targets such as VE-cadherin, COX-2, iNOS, VEGF, bFGF, FGF2,MMP2,MMP9,IL-1β,IL-6 play a role in inhibiting melanoma angiogenesis. Effective excavation of natural products can not only clarify the mechanism of drug action and key targets, but also help to promote the preclinical research of natural products for melanoma treatment and further promote the development of new clinical drugs, which will bring the gospel to the vast number of patients who are deeply afflicted by melanoma.

ENG is a Biomarker of Prognosis and Angiogenesis in Liver Cancer, and Promotes the Differentiation of Tumor Cells into Vascular ECs

BACKGROUND

Liver cancer is a highly lethal malignancy with frequent recurrence, widespread metastasis, and low survival rates. The aim of this study was to explore the role of Endoglin (ENG) in liver cancer progression, as well as its impacts on angiogenesis, immune cell infiltration, and the therapeutic efficacy of sorafenib.

METHODS

A comprehensive evaluation was conducted using online databases Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA), 76 pairs of clinical specimens of tumor and adjacent non-tumor liver tissue, and tissue samples from 32 hepatocellular carcinoma (HCC) patients treated with sorafenib. ENG expression levels were evaluated using quantitative Reverse Transcription Polymerase Chain Reaction (qRT-PCR), Western blot, and immunohistochemical analysis. Cox regression analysis, Spearman rank correlation analysis, and survival analysis were used to assess the results. Functional experiments included Transwell migration assays and tube formation assays with Human Umbilical Vein Endothelial Cells (HUVECs).

RESULTS

Tumor cells exhibited retro-differentiation into endothelial-like cells, with a significant increase in ENG expression in these tumor-derived endothelial cells (TDECs). High expression of ENG was associated with more aggressive cancer characteristics and worse patient prognosis. Pathway enrichment and functional analyses identified ENG as a key regulator of immune responses and angiogenesis in liver cancer. Further studies confirmed that ENG increases the expression of Collagen type Iα1 (COL1A1), thereby promoting angiogenesis in liver cancer. Additionally, HCC patients with elevated ENG levels responded well to sorafenib treatment.

CONCLUSIONS

This study found that ENG is an important biomarker of prognosis in liver cancer. Moreover, ENG is associated with endothelial cell differentiation in liver cancer and plays a crucial role in formation of the tumor vasculature. The assessment of ENG expression could be a promising strategy to identify liver cancer patients who might benefit from targeted immunotherapies.

Vasculogenic mimicry-related gene prognostic index for predicting prognosis, immune microenvironment in clear cell renal cell carcinoma

Background

Clear cell renal cell carcinoma (ccRCC) is a highly aggressive cancer associated with higher death rates. However, traditional anti-angiogenic therapies have limited effectiveness due to drug resistance. Vascular mimicry (VM) provides a different way for tumors to develop blood vessels without relying on endothelial cells or angiogenesis. However, the intricate mechanisms and interplay between it and the immune microenvironment in ccRCC remain unclear.

Methods

A PubMed and GeneCards literature review was conducted to identify VM-related genes (VMRGs). VMRGs expression profiles were obtained from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO), developing a novel VM risk score model and nomogram for ccRCC. The EBI ArrayExpress database (the validation set) was obtained to validate the prognostic model. The relationship between VMRGs risk score clinical characteristics and immune infiltration was investigated. Finally, the expression of six model VMRGs was validated using single-cell analysis, GEPIA, Human Protein Atlas (HPA), and quantitative Real-time PCR (qRT-PCR).

Results

Cox regression analysis and nomogram identified L1CAM, TEK, CLDN4, EFNA1, SERPINF1, and MALAT1 as independent prognostic risk factors, which could be used to stratify the ccRCC population into two risk groups with distinct immune profiles and responsiveness to immunotherapy. The results of single-cell analysis, GEPIA, HPA, and qRT-PCR validated the model genes' expression.

Conclusions

Our novel findings constructed a convenient and reliable 6 gene signatures as potential immunologic and prognostic biomarkers of VM in ccRCC.

Strong Activation of ID1, ID2, and ID3 Genes Is Coupled with the Formation of Vasculogenic Mimicry Phenotype in Melanoma Cells

Gene expression patterns are very sensitive to external influences and are reflected in phenotypic changes. It was previously described that transferring melanoma cells from a plastic surface to Matrigel led to formation of de novo vascular networks-vasculogenic mimicry-that are characteristic to a stemness phenotype in aggressive tumors. Up to now there was no detailed data about the gene signature accompanying this process. Here, we show that this transfer shortly led to extremely strong epigenetic changes in gene expression in the melanoma cells. We observed that on Matrigel numerous genes controlling ribosome biogenesis were upregulated. However, most of the activated genes were inhibitors of the differentiation genes (ID1, ID2, and ID3). At the same time, the genes that control differentiation were downregulated. Both the upregulated and the downregulated genes are simultaneously targeted by different transcription factors shaping sets of co-expressed genes. The specific group of downregulated genes shaping contacts with rDNA genes are also associated with the H3K27me3 mark and with numerous lincRNAs and miRNAs. We conclude that the stemness phenotype of melanoma cells is due to the downregulation of developmental genes and formation of dedifferentiated cells.

EBV-associated epithelial cancers cells promote vasculogenic mimicry formation via a secretory cross-talk with the immune microenvironment

Background: Vasculogenic mimicry (VM) induced by Epstein-Barr virus (EBV) infection plays an important role in resistance to anti-vascular endothelial growth factor (VEGF) therapy in EBV-associated epithelial cancers; however, the interaction between VM and the immune microenvironment has not been systematically investigated. Methods: IHC and multiplex IHC analysis the relationships among tumour-associated macrophage (TAM), VM and EBV infection in EBV-associated epithelial cancer biopsies. In vitro and in vivo evidence using CRISPR-Cas9 system engineered EBV-infected epithelial cancer cells and mouse models support functional role and mechanism for M2c-like macrophages in the VM formation. The prediction of VM in the effectiveness of anti-angiogenic agent was analysed using clinical datasets. Results: EBV-associated epithelial cancer biopsies revealed that infiltration of the TAM surrounding the VM is closely associated with EBV infection. AKT/mTOR/HIF-1α pathway in EBV-infected epithelial cancer cells control the secretion of CCL5 and CSF-1, enabling the recruitment of monocytes and their differentiation into M2c macrophages which promote VM formation by MMP9. Combination of anti-angiogenesis agents and HIF-1α inhibitor caused marked decreases in CD31-positive micro-vessels, VM, and M2c-like macrophages. VM scores can be used as biomarkers to predict the efficacy of anti-angiogenic agent therapy in EBV-associated epithelial cancers. Conclusions: Our findings define a secretory cross-talk between tumour cells and the immune microenvironment in EBV-associated epithelial cancer, revealing an unexpected role of EBV in epithelial cancer cells, controlling VM formation via M2c-like macrophages.

Unveiling the Dynamic Interplay between Cancer Stem Cells and the Tumor Microenvironment in Melanoma: Implications for Novel Therapeutic Strategies

Cutaneous melanoma still represents a significant health burden worldwide, being responsible for the majority of skin cancer deaths. Key advances in therapeutic strategies have significantly improved patient outcomes; however, most patients experience drug resistance and tumor relapse. Cancer stem cells (CSCs) are a small subpopulation of cells in different tumors, including melanoma, endowed with distinctive capacities of self-renewal and differentiation into bulk tumor cells. Melanoma CSCs are characterized by the expression of specific biomarkers and intracellular pathways; moreover, they play a pivotal role in tumor onset, progression and drug resistance. In recent years, great efforts have been made to dissect the molecular mechanisms underlying the protumor activities of melanoma CSCs to provide the basis for novel CSC-targeted therapies. Herein, we highlight the intricate crosstalk between melanoma CSCs and bystander cells in the tumor microenvironment (TME), including immune cells, endothelial cells and cancer-associated fibroblasts (CAFs), and its role in melanoma progression. Specifically, we discuss the peculiar capacities of melanoma CSCs to escape the host immune surveillance, to recruit immunosuppressive cells and to educate immune cells toward an immunosuppressive and protumor phenotype. We also address currently investigated CSC-targeted strategies that could pave the way for new promising therapeutic approaches for melanoma care.

Role of N6-methyladenosine in tumor neovascularization

Tumor neovascularization is essential for the growth, invasion, and metastasis of tumors. Recent studies have highlighted the significant role of N6-methyladenosine (m6A) modification in regulating these processes. This review explores the mechanisms by which m6A influences tumor neovascularization, focusing on its impact on angiogenesis and vasculogenic mimicry (VM). We discuss the roles of m6A writers, erasers, and readers in modulating the stability and translation of angiogenic factors like vascular endothelial growth factor (VEGF), and their involvement in key signaling pathways such as PI3K/AKT, MAPK, and Hippo. Additionally, we outline the role of m6A in vascular-immune crosstalk. Finally, we discuss the current development of m6A inhibitors and their potential applications, along with the contribution of m6A to anti-angiogenic therapy resistance. Highlighting the therapeutic potential of targeting m6A regulators, this review provides novel insights into anti-angiogenic strategies and underscores the need for further research to fully exploit m6A modulation in cancer treatment. By understanding the intricate role of m6A in tumor neovascularization, we can develop more effective therapeutic approaches to inhibit tumor growth and overcome treatment resistance. Targeting m6A offers a novel approach to interfere with the tumor's ability to manipulate its microenvironment, enhancing the efficacy of existing treatments and providing new avenues for combating cancer progression.

Immunosuppressive tumor microenvironment in the progression, metastasis, and therapy of hepatocellular carcinoma: from bench to bedside

Hepatocellular carcinoma (HCC) is a highly heterogeneous malignancy with high incidence, recurrence, and metastasis rates. The emergence of immunotherapy has improved the treatment of advanced HCC, but problems such as drug resistance and immune-related adverse events still exist in clinical practice. The immunosuppressive tumor microenvironment (TME) of HCC restricts the efficacy of immunotherapy and is essential for HCC progression and metastasis. Therefore, it is necessary to elucidate the mechanisms behind immunosuppressive TME to develop and apply immunotherapy. This review systematically summarizes the pathogenesis of HCC, the formation of the highly heterogeneous TME, and the mechanisms by which the immunosuppressive TME accelerates HCC progression and metastasis. We also review the status of HCC immunotherapy and further discuss the existing challenges and potential therapeutic strategies targeting immunosuppressive TME. We hope to inspire optimizing and innovating immunotherapeutic strategies by comprehensively understanding the structure and function of immunosuppressive TME in HCC.

Functional roles of microRNAs in vasculogenic mimicry and resistance to therapy in human cancers: an update

INTRODUCTION

Vasculogenic mimicry (VM) alludes to the ability of cancer cells to organize on three-dimensional channel-like structures to obtain nutrients and oxygen. This mechanism confers an aggressive phenotype, metastatic potential, and resistance to chemotherapy resulting in a poor prognosis. Recent studies have been focused on the identification of microRNAs (miRNAs) that regulate the VM representing potential therapeutic targets in cancer.

AREAS COVERED

An overview of the roles of miRNAs on VM development and their functional relationships with tumor microenvironment. The functions of cancer stem-like cells in VM, and resistance to therapy are also discussed. Moreover, the modulation of VM by natural compounds is explored. The clinical significance of deregulated miRNAs as potential therapeutic targets in tumors showing VM is further highlighted.

EXPERT OPINION

The miRNAs are regulators of protein-encoding genes involved in VM; however, their specific expression signatures with clinical value in large cohorts of patients have not been established yet. We considered that genomic profiling of miRNAs could be useful to define some hallmarks of tumors such as stemness, drug resistance, and VM in cancer patients. However, additional studies are needed to establish the relevant role of miRNAs as effective therapeutic targets in tumors that have developed VM.

The in vitro dynamics of pseudo-vascular network formation

BACKGROUND/OBJECTIVES

Pseudo-vascular network formation in vitro is considered a key characteristic of vasculogenic mimicry. While many cancer cell lines form pseudo-vascular networks, little is known about the spatiotemporal dynamics of these formations.

METHODS

Here, we present a framework for monitoring and characterising the dynamic formation and dissolution of pseudo-vascular networks in vitro. The framework combines time-resolved optical microscopy with open-source image analysis for network feature extraction and statistical modelling. The framework is demonstrated by comparing diverse cancer cell lines associated with vasculogenic mimicry, then in detecting response to drug compounds proposed to affect formation of vasculogenic mimics. Dynamic datasets collected were analysed morphometrically and a descriptive statistical analysis model was developed in order to measure stability and dissimilarity characteristics of the pseudo-vascular networks formed.

RESULTS

Melanoma cells formed the most stable pseudo-vascular networks and were selected to evaluate the response of their pseudo-vascular networks to treatment with axitinib, brucine and tivantinib. Tivantinib has been found to inhibit the formation of the pseudo-vascular networks more effectively, even in dose an order of magnitude less than the two other agents.

CONCLUSIONS

Our framework is shown to enable quantitative analysis of both the capacity for network formation, linked vasculogenic mimicry, as well as dynamic responses to treatment.

The role of vasculature and angiogenesis in respiratory diseases

In European countries, nearly 10% of all hospital admissions are related to respiratory diseases, mainly chronic life-threatening diseases such as COPD, pulmonary hypertension, IPF or lung cancer. The contribution of blood vessels and angiogenesis to lung regeneration, remodeling and disease progression has been increasingly appreciated. The vascular supply of the lung shows the peculiarity of dual perfusion of the pulmonary circulation (vasa publica), which maintains a functional blood-gas barrier, and the bronchial circulation (vasa privata), which reveals a profiled capacity for angiogenesis (namely intussusceptive and sprouting angiogenesis) and alveolar-vascular remodeling by the recruitment of endothelial precursor cells. The aim of this review is to outline the importance of vascular remodeling and angiogenesis in a variety of non-neoplastic and neoplastic acute and chronic respiratory diseases such as lung infection, COPD, lung fibrosis, pulmonary hypertension and lung cancer.

Vascular mimicry in zebrafish fin regeneration: how macrophages build new blood vessels

Vascular mimicry has been thoroughly investigated in tumor angiogenesis. In this study, we demonstrate for the first time that a process closely resembling tumor vascular mimicry is present during physiological blood vessel formation in tissue regeneration using the zebrafish fin regeneration assay. At the fin-regenerating front, vasculature is formed by mosaic blood vessels with endothelial-like cells possessing the morphological phenotype of a macrophage and co-expressing both endothelial and macrophage markers within single cells. Our data demonstrate that the vascular segments of the regenerating tissue expand, in part, through the transformation of adjacent macrophages into endothelial-like cells, forming functional, perfused channels and contributing to the de novo formation of microvasculature. Inhibiting the formation of tubular vascular-like structures by CVM-1118 prevents vascular mimicry and network formation resulting in a 70% shorter regeneration area with 60% reduced vessel growth and a complete absence of any signs of regeneration in half of the fin area. Additionally, this is associated with a significant reduction in macrophages. Furthermore, depleting macrophages using macrophage inhibitor PLX-3397, results in impaired tissue regeneration and blood vessel formation, namely a reduction in the regeneration area and vessel network by 75% in comparison to controls.

Hypomethylation-associated LINC00987 downregulation induced lung adenocarcinoma progression by inhibiting the phosphorylation-mediated degradation of SND1

DNA methylation, an epigenetic regulatory mechanism dictating gene transcription, plays a critical role in the occurrence and development of cancer. However, the molecular underpinnings of LINC00987 methylation in the regulation of lung adenocarcinoma (LUAD) remain elusive. This study investigated LINC00987 expression in LUAD patients through analysis of The Cancer Genome Atlas data sets. Quantitative real-time polymerase chain reaction (RT-qPCR) and fluorescence in situ hybridization assays were used to assess LINC00987 expression in LUAD. The bisulfite genomic sequence PCR (BSP) assay was used to determine the methylation levels of the LINC00987 promoter. The interaction between LINC00987 and SND1 was elucidated via immunoprecipitation and RNA pull-down assays. The functional significance of LINC00987 and SND1 in Calu-3 and NCI-H1688 cells was evaluated in vitro through CCK-8, EdU, Transwell, flow cytometry, and vasculogenic mimicry (VM) tube formation assays. LINC00987 expression decreased in LUAD concomitant with hypermethylation of the promoter region, while hypomethylation of the LINC00987 promoter in LUAD tissues correlated with tumor progression. Treatment with 5-Aza-CdR augmented LINC00987 expression and inhibited tumor growth. Mechanistically, LINC00987 overexpression impeded LUAD progression and VM through direct binding with SND1, thereby facilitating its phosphorylation and subsequent degradation. Additionally, overexpression of SND1 counteracted the adverse effects of LINC00987 downregulation on cell proliferation, apoptosis, cell migration, invasion, and VM in LUAD in vitro. In conclusion, this pioneering study focuses on the expression and function of LINC00987 and reveals that hypermethylation of the LINC00987 gene may contribute to LUAD progression. LINC00987 has emerged as a potential tumor suppressor gene in tumorigenesis through its binding with SND1 to facilitate its phosphorylation and subsequent degradation.

Engineered in vivo and in vitro tumor model recapitulates vasculogenic mimicry signatures in melanoma

Vasculogenic mimicry (VM) describes a process by which tumor cells formed a novel microcirculation pattern in an endothelial cell-free manner. Clinically, VM is associated with aggressive phenotype and poor patient survival. However, the current models for investigating VM include 2D monolayer cultures, Matrigel-based cultures, and animal models, each of which has limitations. Matrigel-based models often exhibit batch-to-batch variations, while in vivo tumor models currently produce insufficient amounts of VM. There is currently no suitable tumor model to discover new therapeutic targets against VM. Herein, we establish an extracellular matrix (ECM)-based engineered tumor model in vivo and in vitro. In this study, we demonstrate that matrix proteins enhanced the VM formation in the engineered xenograft model. Furthermore, we also investigated the role of collagen/fibronectin (FN) in melanoma progression and VM formation. Compared with cells cultured on TCPS plates, the B16F10 cells cultured on collagen/FN coated plates showed increased proliferation and stemness, and significantly enhanced invasion and formation of VM networks. Molecular mechanism analysis showed that Integrin/VE-cadherin/EphA2/PI3K/MMP-2 signaling pathways are responsible for VM formation. Our results indicate that collagen/FN matrix plays an important role in VM formation in melanoma, suggesting that ECM protein is a potential therapeutic target for anti-VM therapy for melanoma.

Correlation of functional magnetic resonance imaging features of primary central nervous system lymphoma with vasculogenic mimicry and reticular fibers

Objective

To deepen the imaging-pathological mechanism of primary central nervous system lymphoma (PCNSL) and provide a theoretical basis for clinical diagnosis and treatment, the functional magnetic resonance imaging (fMRI) characteristics of PCNSL were analyzed, and the relationship between the fMRI characteristics and vasculogenic mimicry (VM) and reticular fiber in PCNSL was discussed.

Methods

Ninety-six patients with PCNSL treated in our hospital were divided into three groups according to the pathological examination results, including strong positive group of VM (n = 40), weak positive group of VM (n = 56), strong positive group of reticular fiber (n = 45) and weak positive group of reticular fiber (n = 51). The levels of augmentation index and apparent diffusion coefficient (ADC) were compared among the groups. receiver operator characteristic (ROC) curve analysis was used to analyze the clinical value of ADC value in differential diagnosis of PCNSL.

Results

The levels of augmentation index in the strong positive group of VM were significantly higher than that in the weak positive group of VM, and the ADC value in the strong positive group of VM was significantly lower than that in the weak positive group of VM (P < 0.001). The levels of augmentation index in the strong positive group of reticular fiber were significantly higher than that in the weak positive group of reticular fiber, and ADC value in the strong positive group of reticular fiber was significantly lower than that in reticular fiber weak positive group (P < 0.001). Pearson correlation analysis showed that the levels of augmentation index were positively correlated with VM and reticular fiber (r = 0.529, 0.548, P < 0.001) and the ADC value was negatively correlated with VM and reticular fiber (r = -0.485, -0.513, P < 0.001). There was a significant negative correlation between necrotic lesions and VM (r = -0.185, P < 0.05). The area under the curve (AUC) values of average ADC value, minimum ADC value, and maximum ADC value for individual differential diagnosis of PCNSL were 0.920, 0.901, and 0.702, while the AUC of the combined differential diagnosis was 0.985, with a sensitivity of 95.00 % and a specificity of 92.70 %.

Conclusion

The levels of augmentation index and the ADC value of PCNSL focus are significantly correlated with VM and reticular fiber, and there is a strong negative correlation between necrotic lesions and VM. MRI imaging technology is of great significance in revealing the biological behavior of PCNSL, which can effectively reveal the relationship between VM and reticular fibers and the MRI characteristics in PCNSL, thereby providing a new imaging basis for the clinical diagnosis and treatment of PCNSL.

HNRNPA2B1 stabilizes NFATC3 levels to potentiate its combined actions with FOSL1 to mediate vasculogenic mimicry in GBM cells

BACKGROUND

Vasculogenic mimicry (VM) is an enigmatic physiological feature that influences blood supply within glioblastoma (GBM) tumors for their sustained growth. Previous studies identify NFATC3, FOSL1 and HNRNPA2B1 as significant mediators of VEGFR2, a key player in vasculogenesis, and their molecular relationships may be crucial for VM in GBM.

AIMS

The aim of this study was to understand how NFATC3, FOSL1 and HNRNPA2B1 collectively influence VM in GBM.

METHODS

We have investigated the underlying gene regulatory mechanisms for VM in GBM cell lines U251 and U373 in vitro and in vivo. In vitro cell-based assays were performed to explore the role of NFATC3, FOSL1 and HNRNPA2B1 in GBM cell proliferation, VM and migration, in the context of RNA interference (RNAi)-mediated knockdown alongside corresponding controls. Western blotting and qRT-PCR assays were used to examine VEGFR2 expression levels. CO-IP was employed to detect protein-protein interactions, ChIP was used to detect DNA-protein complexes, and RIP was used to detect RNA-protein complexes. Histochemical staining was used to detect VM tube formation in vivo.

RESULTS

Focusing on NFATC3, FOSL1 and HNRNPA2B1, we found each was significantly upregulated in GBM and positively correlated with VM-like cellular behaviors in U251 and U373 cell lines. Knockdown of NFATC3, FOSL1 or HNRNPA2B1 each resulted in decreased levels of VEGFR2, a key growth factor gene that drives VM, as well as the inhibition of proliferation, cell migration and extracorporeal VM activity. Chromatin immunoprecipitation (ChIP) studies and luciferase reporter gene assays revealed that NFATC3 binds to the promoter region of VEGFR2 to enhance VEGFR2 gene expression. Notably, FOSL1 interacts with NFATC3 as a co-factor to potentiate the DNA-binding capacity of NFATC3, resulting in enhanced VM-like cellular behaviors. Also, level of NFATC3 protein in cells was enhanced through HNRNPA2B1 binding of NFATC3 mRNA. Furthermore, RNAi-mediated silencing of NFATC3, FOSL1 and HNRNPA2B1 in GBM cells reduced their capacity for tumor formation and VM-like behaviors in vivo.

CONCLUSION

Taken together, our findings identify NFATC3 as an important mediator of GBM tumor growth through its molecular and epistatic interactions with HNRNPA2B1 and FOSL1 to influence VEGFR2 expression and VM-like cellular behaviors.

Selenium nanoparticles stabilized by Sargassum fusiforme polysaccharides: Synthesis, characterization and bioactivity

Selenium nanoparticles (SeNPs) are a potential tumor therapeutic drug and have attracted widespread attention due to their high bioavailability and significant anticancer activity. However, the poor water solubility and degradability of selenium nanoparticles severely limit their application. In this study, spherical selenium nanoparticles with a particle size of approximately 50 nm were prepared by using Sargassum fusiforme polysaccharide (SFPS) as a modifier and Tween-80 as a stabilizer. The results of in vitro experiments showed that Sargassum fusiforme polysaccharide-Tween-80-Selenium nanoparticles (SFPS-Tw-SeNPs) had a significant inhibitory effect on A549 cells, with an IC50 value of 6.14 μg/mL, and showed antitumor cell migration and invasion ability against A549 cells in scratch assays and cell migration and invasion assays (transwell assays). Western blot experiments showed that SFPS-Tw-SeNPs could inhibit the expression of tumor migration- and invasion-related proteins. These results suggest that SFPS-Tw-SeNPs may be potential tumor therapeutic agents, especially for the treatment of human lung cancer.

When DNA Mutations Interplay with Cellular Proliferation: A Narrative History of Theories of Carcinogenesis

While cancer is one of the most documented diseases, how normal cells become cancerous is still debated. To address this question, in the first part of this review, we investigated the long succession of theories of carcinogenesis since antiquity. Initiated by Hippocrates, Aristotle, and Galen, the humoral theory interpreted cancer as an excess of acid, the black bile. The discovery of the circulation of blood by Harvey in 1628 destroyed the basis of the humoral theory but revived the spontaneous generation hypothesis which was also promoted by Aristotle. In 1859, the theory of microbes promoted by Pasteur demonstrated the irrelevance of this last theory and contributed to the emergence of the germ cancer theory, opposed to the cellular theory of cancer, in which cancer was supposed to be caused by microbes or transformed cells, respectively. These theories were progressively refined by the notions of initiation, promotion, and progression thanks to advances in mutagenesis and cellular proliferation. In the second part of this review, recent discoveries and paradigms in carcinogenesis, notably the role of the protein ATM, a major actor of the stress response involved in both mutagenesis and cellular proliferation, were discussed to better understand the current state of the art of carcinogenesis.

PD-L1 knockdown suppresses vasculogenic mimicry of non-small cell lung cancer by modulating ZEB1-triggered EMT

BACKGROUND

PD-L1 overexpression is commonly observed in various malignancies and is strongly correlated with poor prognoses for cancer patients. Moreover, PD-L1 has been shown to play a significant role in promoting angiogenesis and epithelial-mesenchymal transition (EMT) processes across different cancer types.

METHODS

The relationship between PD-L1 and vasculogenic mimicry as well as epithelial-mesenchymal transition (EMT) was explored by bioinformatics approach and immunohistochemistry. The functions of PD-L1 in regulating the expression of ZEB1 and the EMT process were assessed by Western blotting and q-PCR assays. The impact of PD-L1 on the migratory and proliferative capabilities of A549 and H1299 cells was evaluated through wound healing, cell invasion, and CCK8 assays following siRNA-mediated PD-L1 knockdown. Tube formation assay was utilized to evaluate the presence of VM structures.

RESULTS

In this study, increased PD-L1 expression was observed in A549 and H1299 cells compared to normal lung epithelial cells. Immunohistochemical analysis revealed a higher prevalence of VM structures in the PD-L1-positive group compared to the PD-L1-negative group. Additionally, high PD-L1 expression was also found to be significantly associated with advanced TNM stage and increased metastasis. Following PD-L1 knockdown, NSCLC cells exhibited a notable reduction in their ability to form tube-like structures. Moreover, the levels of key EMT and VM-related markers, including N-cadherin, MMP9, VE-cadherin, and VEGFA, were significantly decreased, while E-cadherin expression was upregulated. In addition, the migration and proliferation capacities of both cell lines were significantly inhibited after PD-L1 or ZEB1 knockdown.

CONCLUSIONS

Knockdown PD-L1 can inhibit ZEB1-mediated EMT, thereby hindering the formation of VM in NSCLC.

Role of cancer stem cell ecosystem on breast cancer metastasis and related mouse models

Breast cancer metastasis is responsible for most breast cancer-related deaths and is influenced by many factors within the tumor ecosystem, including tumor cells and microenvironment. Breast cancer stem cells (BCSCs) constitute a small population of cancer cells with unique characteristics, including their capacity for self-renewal and differentiation. Studies have shown that BCSCs not only drive tumorigenesis but also play a crucial role in promoting metastasis in breast cancer. The tumor microenvironment (TME), composed of stromal cells, immune cells, blood vessel cells, fibroblasts, and microbes in proximity to cancer cells, is increasingly recognized for its crosstalk with BCSCs and role in BCSC survival, growth, and dissemination, thereby influencing metastatic ability. Hence, a thorough understanding of BCSCs and the TME is critical for unraveling the mechanisms underlying breast cancer metastasis. In this review, we summarize current knowledge on the roles of BCSCs and the TME in breast cancer metastasis, as well as the underlying regulatory mechanisms. Furthermore, we provide an overview of relevant mouse models used to study breast cancer metastasis, as well as treatment strategies and clinical trials addressing BCSC-TME interactions during metastasis. Overall, this study provides valuable insights for the development of effective therapeutic strategies to reduce breast cancer metastasis.

Constructing a novel prognostic model for triple-negative breast cancer based on genes associated with vasculogenic mimicry

BACKGROUND

Research has shown a connection between vasculogenic mimicry (VM) and cancer progression. However, the functions of genes related to VM in the emergence and progression of TNBC have not been completely elucidated.

METHODS

A survival risk model was constructed by screening biomarkers using DESeq2 and WGCNA based on public TNBC transcriptome data. Furthermore, gene set enrichment analysis was performed, and tumor microenvironment and drug sensitivity were analyzed. The selected biomarkers were validated via quantitative PCR detection, immunohistochemical staining, and protein detection in breast cancer cell lines. Biomarkers related to the proliferation and migration of TNBC cells were validated via in vitro experiments.

RESULTS

The findings revealed that 235 target genes were connected to the complement and coagulation cascade pathways. The risk score was constructed using KCND2, NRP1, and VSTM4. The prognosis model using the risk score and pathological T stage yielded good validation results. The clinical risk of TNBC was associated with the angiogenesis signaling pathway, and the low-risk group exhibited better sensitivity to immunotherapy. Quantitative PCR and immunohistochemistry indicated that the expression levels of KCND2 in TNBC tissues were higher than those in adjacent nontumor tissues. In the TNBC cell line, the protein expression of KCND2 was increased. Knockdown of KCND2 and VSTM4 inhibited the proliferation and migration of TNBC cells in vitro.

CONCLUSIONS

In this study, three VM-related biomarkers were identified, including KCND2, NRP1, and VSTM4. These findings are likely to aid in deepening our understanding of the regulatory mechanism of VM in TNBC.

The deubiquitinase USP7 and E3 ligase TRIM21 regulate vasculogenic mimicry and malignant progression of RMS by balancing SNAI2 homeostasis

BACKGROUND

Rhabdomyosarcoma (RMS) is a rare malignancy and the most common soft tissue sarcoma in children. Vasculogenic mimicry (VM) is a novel tumor microcirculation model different from traditional tumor angiogenesis, which does not rely on endothelial cells to provide sufficient blood supply for tumor growth. In recent years, VM has been confirmed to be closely associated with tumor progression. However, the ability of RMS to form VM has not yet been reported.

METHODS

Immunohistochemistry, RT-qPCR and western blot were used to test the expression level of SNAI2 and its clinical significance. The biological function in regulating vasculogenic mimicry and malignant progression of SNAI2 was examined both in vitro and in vivo. Mass spectrometry, co-immunohistochemistry, immunofluorescence staining, and ubiquitin assays were performed to explore the regulatory mechanism of SNAI2.

RESULTS

Our study indicated that SNAI2 was abnormally expressed in patients with RMS and RMS cell lines and promoted the proliferation and metastasis of RMS. Through cell tubule formation experiments, nude mice Matrigel plug experiments, and immunohistochemistry (IHC), we confirmed that RMS can form VM and that SNAI2 promotes the formation of VM. Due to SNAI2 is a transcription factor that is not easily drugged, we used Co-IP combined with mass spectrometry to screen for the SNAI2-binding protein USP7 and TRIM21. USP7 depletion inhibited RMS VM formation, proliferation and metastasis by promoting SNAI2 degradation. We further demonstrated that TRIM21 is expressed at low levels in human RMS tissues and inhibits VM in RMS cells. TRIM21 promotes SNAI2 protein degradation through ubiquitination in the RMS. The deubiquitinase USP7 and E3 ligase TRIM21 function in an antagonistic rather than competitive mode and play a key role in controlling the stability of SNAI2 to determine the VM formation and progression of RMS.

CONCLUSION

Our findings reveal a previously unknown mechanism by which USP7 and TRIM21 balance the level of SNAI2 ubiquitination, determining RMS vasculogenic mimicry, proliferation, and migration. This new mechanism may provide new targeted therapies to inhibit the development of RMS by restoring TRIM21 expression or inhibiting USP7 expression in RMS patients with high SNAI2 protein levels.

N-myc downstream-regulated gene 1 can promote vasculogenic mimicry and angiogenesis in urothelial carcinoma

Urothelial carcinoma (UC) of the bladder is a common cause of cancer-related death worldwide. Vasculogenic mimicry (VM) is a process by which the malignant cells can generate vascular-like structures formed of periodic acid-Schiff (PAS) positive/CD31 negative extracellular matrix independent of angiogenesis and thus promotes tumor progression. N-myc downstream-regulated gene 1 (NDRG1) is a protein that can modulate tumor angiogenesis; however, its role in regulating tumor angiogenesis and VM formation has not been previously investigated in UC. This study aims to evaluate the role of intra-tumor microvessel density (MVD) (as a surrogate measure of angiogenesis), VM, and NDRG1 in UC and their correlation with different clinicopathologic features, then assess the correlation between them in UC. Sixty specimens of UC of the bladder were included. PAS-CD31 immunohistochemical double staining method was used to evaluate the intra-tumor MVD and VM. Immunohistochemical expression of NDRG1 was also examined. VM and NDRG1 expression were detected in 41.7% and 83.3% of UC specimens respectively. The mean of intra-tumor MVD, VM area, and NDRG1 was significantly higher in tumors with higher grade, lymphovascular invasion, and higher T stage. NDRG1 expression was positively correlated with MVD and VM. We can suggest that MVD, VM, and NDRG1 may serve as poor prognostic markers for UC. The positive correlation between NDRG1 and both MVD and VM may provide the first evidence that NDRG1 can induce tumor angiogenesis and VM in UC which may offer a novel pathway for further therapeutic strategies.

The spectrum of microvascular patterns in adult diffuse glioma and their correlation with tumor grade

BACKGROUND

Primary brain tumors constitute the leading cause of cancer-related mortality. Among them, adult diffuse gliomas are the most common type, affecting the cerebral hemispheres and displaying a diffuse infiltrative pattern of growth in the surrounding neuropil that accounts for about 80% of all primary intracranial tumors. The hallmark feature of gliomas is blood vessel proliferation, which plays an important role in tumor growth, tumor biological behavior, and disease outcome. High-grade gliomas exhibit increased vascularity, the worst prognosis, and lower survival rates. Several angiogenic receptors and factors are upregulated in glioblastomas and stimulate angiogenesis signaling pathways by means of activating oncogenes and/or down-regulating tumor-suppressor genes. Existing literature has emphasized that different microvascular patterns (MVPs) are displayed in different subtypes of adult diffuse gliomas.

METHODS

We examined the distribution and biological characteristics of different MVPs in 50 patients with adult diffuse gliomas. Haematoxylin and eosin staining results, along with periodic acid-Schiff and CD34 dual-stained sections, were examined to assess the vascular patterns and correlate with different grades of diffuse glioma.

RESULTS

The present observational study on adult diffuse glioma evaluated tumor grade and MVPs. Microvascular sprouting was the most common pattern, while a bizarre pattern (type 2) was associated with the presence of a high-grade glioma. Vascular mimicry was observed in 6% of cases, all of which were grade 4 gliomas.

CONCLUSIONS

This study supplements the role of neo-angiogenesis and aberrant vasculature patterns in the grading and progression of adult diffuse gliomas, which can be future targets for planning treatment strategies.

HSP27 promotes vasculogenic mimicry formation in human salivary adenoid cystic carcinoma via the AKT-MMP-2/9 pathway

PURPOSE

To explore the role and mechanism of heat shock protein 27 (HSP27) in SACC VM formation.

STUDY DESIGN

Immunohistochemistry and double staining with cluster of differentiation 31 (CD31) and periodic acid-Schiff (PAS) were used to detect HSP27 expression and VM in 70 SACC tissue samples separately. Quantitative real-time polymerase chain reaction (qRT-PCR), western blot analysis, and immunofluorescence were used to detect gene and protein expression. HSP27 in SACC cells were overexpression or downregulated by transfecting HSP27 or short hairpin RNA target HSP27 (sh-HSP27). The migration and invasion abilities of SACC cells were detected using wound healing and Transwell invasion assays. The VM formation ability of the cells in vitro was detected using a Matrigel 3-dimensional culture.

RESULTS

HSP27 expression was positively correlated with VM formation and affected the prognosis of patients. In vitro, HSP27 upregulation engendered VM formation and the invasion and migration of SACC cells. Mechanistically, HSP27 upregulation increased Akt phosphorylation and subsequently increased downstream matrix metalloproteinase 2 and 9 expressions.

CONCLUSION

HSP27 may plays an important role in VM formation in SACC via the AKT-MMP-2/9 signalling pathway.

LIFU/MMP-2 dual-responsive release of repurposed drug disulfiram from nanodroplets for inhibiting vasculogenic mimicry and lung metastasis in triple-negative breast cancer

BACKGROUND

Vasculogenic mimicry (VM), when microvascular channels are formed by cancer cells independent of endothelial cells, often occurs in deep hypoxic areas of tumors and contributes to the aggressiveness and metastasis of triple-negative breast cancer (TNBC) cells. However, well-developed VM inhibitors exhibit inadequate efficacy due to their low drug utilization rate and limited deep penetration. Thus, a cost-effective VM inhibition strategy needs to be designed for TNBC treatment.

RESULTS

Herein, we designed a low-intensity focused ultrasound (LIFU) and matrix metalloproteinase-2 (MMP-2) dual-responsive nanoplatform termed PFP@PDM-PEG for the cost-effective and efficient utilization of the drug disulfiram (DSF) as a VM inhibitor. The PFP@PDM-PEG nanodroplets effectively penetrated tumors and exhibited substantial accumulation facilitated by PEG deshielding in a LIFU-mediated and MMP-2-sensitive manner. Furthermore, upon exposure to LIFU irradiation, DSF was released controllably under ultrasound imaging guidance. This secure and controllable dual-response DSF delivery platform reduced VM formation by inhibiting COL1/pro-MMP-2 activity, thereby significantly inhibiting tumor progression and metastasis.

CONCLUSIONS

Considering the safety of the raw materials, controlled treatment process, and reliable repurposing of DSF, this dual-responsive nanoplatform represents a novel and effective VM-based therapeutic strategy for TNBC in clinical settings.

A high-cholesterol diet promotes the intravasation of breast tumor cells through an LDL-LDLR axis

Most metastases in breast cancer occur via the dissemination of tumor cells through the bloodstream. How tumor cells enter the blood (intravasation) is, however, a poorly understood mechanism at the cellular and molecular levels. Particularly uncharacterized is how intravasation is affected by systemic nutrients. High levels of systemic LDL-cholesterol have been shown to contribute to breast cancer progression and metastasis in various models, but the cellular and molecular mechanisms involved are still undisclosed. Here we show that a high- cholesterol diet promotes intravasation in two mouse models of breast cancer and that this could be reverted by blocking LDL binding to LDLR in tumor cells. Moreover, we show that LDL promotes vascular invasion in vitro and the intercalation of tumor cells with endothelial cells, a phenotypic change resembling vascular mimicry (VM). At the molecular level, LDL increases the expression of SERPINE2, previously shown to be required for both VM and intravasation. Overall, our manuscript unravels novel mechanisms by which systemic hypercholesterolemia may affect the onset of metastatic breast cancer by favouring phenotypic changes in breast cancer cells and increasing intravasation.

Pan-cancer dissection of vasculogenic mimicry characteristic to provide potential therapeutic targets

Introduction

Vasculogenic mimicry (VM) represents a novel form of tumor angiogenesis that is associated with tumor invasiveness and drug resistance. However, the VM landscape across cancer types remains poorly understood. In this study, we elucidate the characterizations of VM across cancers based on multi-omics data and provide potential targeted therapeutic strategies.

Methods

Multi-omics data from The Cancer Genome Atlas was used to conduct comprehensive analyses of the characteristics of VM related genes (VRGs) across cancer types. Pan-cancer vasculogenic mimicry score was established to provide a depiction of the VM landscape across cancer types. The correlation between VM and cancer phenotypes was conducted to explore potential regulatory mechanisms of VM. We further systematically examined the relationship between VM and both tumor immunity and tumor microenvironment (TME). In addition, cell communication analysis based on single-cell transcriptome data was used to investigate the interactions between VM cells and TME. Finally, transcriptional and drug response data from the Genomics of Drug Sensitivity in Cancer database were utilized to identify potential therapeutic targets and drugs. The impact of VM on immunotherapy was also further clarified.

Results

Our study revealed that VRGs were dysregulated in tumor and regulated by multiple mechanisms. Then, VM level was found to be heterogeneous among different tumors and correlated with tumor invasiveness, metastatic potential, malignancy, and prognosis. VM was found to be strongly associated with epithelial-mesenchymal transition (EMT). Further analyses revealed cancer-associated fibroblasts can promote EMT and VM formation. Furthermore, the immune-suppressive state is associated with a microenvironment characterized by high levels of VM. VM score can be used as an indicator to predict the effect of immunotherapy. Finally, seven potential drugs targeting VM were identified.

Conclusion

In conclusion, we elucidate the characteristics and key regulatory mechanisms of VM across various cancer types, underscoring the pivotal role of CAFs in VM. VM was further found to be associated with the immunosuppressive TME. We also provide clues for the research of drugs targeting VM. Our study provides an initial overview and reference point for future research on VM, opening up new avenues for therapeutic intervention.