Prediction of the mean transit time using machine learning models based on radiomics features from digital subtraction angiography in moyamoya disease or moyamoya syndrome-a development and validation model study.

Background: Digital subtraction angiography (DSA) is an important technique for diagnosis of moyamoya disease (MMD) or moyamoya syndrome (MMS), and computed tomography perfusion (CTP) is essential for assessing intracranial blood supply. The aim of this study was to assess whether radiomics features based on images of DSA could predict the mean transit time (MTT; outcome of CTP) using machine learning models. Methods: The DSA images and MTT values of adult patients with MMD or MMS, according to the diagnostic guidelines for MMD, as well as control cases, were retrospectively collected in the Guangdong Provincial People's Hospital between January 2018 and December 2020. A total of 93 features were extracted from the images of each case through 3-dimensional (3D) slicer. After features preprocessing and filtering, 3-4 features were selected by the least absolute shrinkage and selection operator (LASSO) regression algorithm. Prediction models were established using random forest (RF) and support vector machine (SVM) for MTT values. Single-factor receiver operating characteristic (ROC) curve analysis and partial-dependence (PD) profiles were conducted to investigate selected features and prediction models. Results: Our results showed that prediction models based on RF models had the best performance in frontal lobe {area under the curve (AUC) [95% confidence interval (CI)] =1.000 (1.000-1.000)], parietal lobe [AUC (95% CI) =1.000 (1.000-1.000)], and basal ganglia/thalamus [AUC (95% CI) =0.922 (0.797-1.000)] in the test set, whereas the SVM model performed the best in the temporal lobe [AUC (95% CI) =0.962 (0.876-1.000)] in the test set. The AUC values in the test set were greater than 0.9. The PD profiles showed good robustness and consistency. Conclusions: Prediction models based on radiomics features extracted from DSA images demonstrate excellent performance in predicting MTT in patients with MMD or MMS, which may provide guidance for future clinical practice.

PCSK9 Inhibition: From Current Advances to Evolving Future.

Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a secretory serine protease synthesized primarily by the liver. It mainly promotes the degradation of low-density lipoprotein receptor (LDL-R) by binding LDL-R, reducing low-density lipoprotein cholesterol (LDL-C) clearance. In addition to regulating LDL-R, PCSK9 inhibitors can also bind Toll-like receptors (TLRs), scavenger receptor B (SR-B/CD36), low-density lipoprotein receptor-related protein 1 (LRP1), apolipoprotein E receptor-2 (ApoER2) and very-low-density lipoprotein receptor (VLDL-R) reducing the lipoprotein concentration and slowing thrombosis. In addition to cardiovascular diseases, PCSK9 is also used in pancreatic cancer, sepsis, and Parkinson's disease. Currently marketed PCSK9 inhibitors include alirocumab, evolocumab, and inclisiran, as well as small molecules, nucleic acid drugs, and vaccines under development. This review systematically summarized the application, preclinical studies, safety, mechanism of action, and latest research progress of PCSK9 inhibitors, aiming to provide ideas for the drug research and development and the clinical application of PCSK9 in cardiovascular diseases and expand its application in other diseases.

Targeting Oxidative Stress and Inflammatory Response for Blood-Brain Barrier Protection in Intracerebral Hemorrhage.

Significance: Blood-brain barrier (BBB) disruption is a major pathological change after intracerebral hemorrhage (ICH) and is both the cause and result of oxidative stress and of the immune response post-ICH. These processes contribute to ICH-induced brain injury. Recent Advances: After the breakdown of cerebral vessels, blood components, including erythrocytes and their metabolites, thrombin, and fibrinogen, can access the cerebral parenchyma through the compromised BBB, triggering oxidative stress and inflammatory cascades. These aggravate BBB disruption and contribute to further infiltration of blood components, resulting in a vicious cycle that exacerbates brain edema and neurological injury after ICH. Experimental and clinical studies have highlighted the role of BBB disruption in ICH-induced brain injury. Critical Issues: In this review, we focus on the strategies to protect the BBB in ICH. Specifically, we summarize the evidence and the underlying mechanisms, including the ICH-induced process of oxidative stress and inflammatory response, and we highlight the potential therapeutic targets to protect BBB integrity after ICH. Future Directions: Future studies should probe the mechanism of ferroptosis as well as oxidative stress-inflammation coupling in BBB disruption after ICH and investigate the effects of antioxidants and immunomodulatory agents in more ICH clinical trials. Antioxid. Redox Signal. 37, 115-134.

Endoscopic Endonasal Approach for Clipping Anterior Communicating Artery Aneurysms From Cadaver Studies and Three-Dimensional Printed Models to a Clinical Case.

OBJECTIVES: Anterior communicating artery (ACoA) aneurysm is one of the most common intracranial aneurysms, and it is also the aneurysm with the highest rupture rate. With the improvement of endoscopic techniques, it is possible to use an endoscopic endonasal approach (EEA) to clip ACoA aneurysms. For further analysis of the EEA for clipping ACoA aneurysms, we used cadaver heads and three-dimensional (3D)-printed models to finish the anatomical study, and we finally selected 1 clinical case to complete the clipping through the EEA. MATERIALS AND METHODS: We first collected 3 cadaver heads to simulate the EEA. Then, the imaging data of 29 real cases of ACoA aneurysm were collected, and the model of an aneurysm was prepared by 3D printing technology; then, the EEA was used to simulate the clipping of the aneurysm model. Finally, a clinical case with 2 ACoA aneurysms was selected to adopt the EEA for clipping. RESULTS: Both the cadaver head and 3D-printed aneurysm model could simulate aneurysm clipping with the EEA. The clinical case of the selected ACoA aneurysm can successfully complete the clipping through the EEA. CONCLUSIONS: 3D-printed models are a good method to study the anatomical characteristics of a surgical approach. For specially selected ACoA aneurysms, the EEA is relatively simple method that can be used to clip the aneurysm successfully. The EEA for clipping ACoA aneurysms is a useful complement to the current traditional craniotomy approaches and endovascular embolization.

Circular RNA circ-ARFIP2 regulates proliferation, migration and invasion in human vascular smooth muscle cells via miR-338-3p-dependent modulation of KDR.

Dysfunction of vascular smooth muscle cells (VSMCs) plays a critical role in the pathogenesis of intracranial aneurysm (IA). Circular RNAs (circRNAs) have been implicated in the pathogenesis of IA by reducing microRNA (miRNA) activity. In this paper, we investigated the precise roles of circRNA ADP ribosylation factor interacting protein 2 (circ-ARFIP2, circ_0021001) in VSMC dysfunction. The levels of circ-ARFIP2, miR-338-3p and kinase insert domain receptor (KDR) were detected by quantitative real-time polymerase chain reaction (qRT-PCR) or western blot. Ribonuclease (RNase) R and subcellular fractionation assays were used to assess the stability and localization of circ-ARFIP2, respectively. Cell viability was detected by Cell Counting Kit-8 (CCK-8) assay, and cell invasion was measured by transwell assay. Cell proliferation was gauged by 5-Ethynyl-2'-Deoxyuridine (EdU) assay. Cell migration was evaluated by transwell and wound-healing assays. Targeted correlations among circ-ARFIP2, miR-338-3p and KDR were validated by dual-luciferase reporter and RNA immunoprecipitation (RIP) assays. Circ-ARFIP2 and KDR were underexpressed and miR-338-3p was overexpressed in the arterial wall tissues of IA patients. Overexpression of circ-ARFIP2 in human umbilical artery smooth muscle cells (HUASMCs) showed a significant promotion in cell proliferation, migration and invasion. Mechanistically, circ-ARFIP2 targeted miR-338-3p, and circ-ARFIP2 regulated cell behaviors by miR-338-3p. KDR was a direct and functional target of miR-338-3p. Moreover, KDR was a downstream effector of circ-ARFIP2 function. Circ-ARFIP2 regulated KDR expression by targeting miR-338-3p. Our present findings demonstrated that the increased level of circ-ARFIP2 enhanced HUASMC proliferation, migration and invasion at least in part by the miR-338-3p/KDR axis.

Erratum to microRNA-188 aggravates contrast-induced apoptosis by targeting SRSF7 in novel isotonic contrast-induced acute kidney injury rat models and renal tubular epithelial cells.

[This corrects the article DOI: 10.21037/atm.2019.07.20.].

The Minimum Distance May Affect Perioperative Complications and Completed Occlusions of Endovascular Treatment for Tandem Intracranial Aneurysms: A Multi-Institutional Retrospective Study.

BACKGROUND: Tandem aneurysms (TAs) are a distinct type of multiple intracranial aneurysms (IAs), the treatment strategies for which remain controversial. We aimed to reveal the clinical and angiographic outcomes of endovascular treatment as well as their risk factors in these complex multiple IAs. METHODS: This multicenter, retrospective follow-up study was carried out in 3 hospitals in China. In total, clinical and angiographical data of 137 patients with 145 lesions (7 patients had bilateral lesions) and 315 TAs were collected. The treatment strategies were divided into full or partial treatment, single- or multiple-session treatment, and coiling (including single coiling and stent-assisted coiling)- or flow-diverting stent (FDS) treatment. Perioperative complications, as well as angiographic and clinical outcomes and their risk factors, were analyzed using univariate analysis and a multiple regression model. RESULTS: Of treated TA lesions, 17 (16.0%) perioperative complications were found. Significant differences were found between the single- and multiple-session treatment groups (p = 0.012). At the latest follow-up, there were no significant differences in the modified Raymond Scale scores between different treatment groups. Significant differences were found in the embolization degree between the coiling and FDS groups (p = 0.038) and between the single common stent (without coiling) and the other treatment groups (p < 0.001). In IAs managed by a single LVIS stent (without coiling), 60% achieved improved or completed occlusion. Multivariate regression analysis found that a shorter minimum distance (odds ratio [OR] 5.967, 95% confidence interval [CI] 1.366-26.074; p = 0.018), multiple-session treatment (OR 9.961, 95% CI 1.707-58.127; p = 0.011), and diabetes (OR 8.106, 95% CI 1.928-34.084; p = 0.004) were predictors of perioperative complications, while shorter minimum distance (OR 5.619, 95% CI 1.493-21.152; p = 0.011), greater diameter ratio (OR 3.621, 95% CI 1.014-12.937; p = 0.048), and greater size ratio (OR 2.424, 95% CI 1.007-5.834; p = 0.048) were predictors of low completed occlusion rate. CONCLUSIONS: Both coiling and FDS can be utilized safely and can achieve similar clinical outcomes. FDS and LVIS are recommended for IAs that do not require embolization but cannot be prevented from being covered by stents. A multiple-session treatment may increase the treatment risk, and the minimum distance may affect the incidence of perioperative complications and completed occlusions. Further hemodynamic and prospective studies on such TAs in close proximity to one another are needed.

miR-647 inhibits glioma cell proliferation, colony formation and invasion by regulating HOXA9.

BACKGROUND: MicroRNA-647 (miR-647) has been reported to regulate tumor development, although its role in glioma remains unclear. METHODS: miR-647 expression in glioma cells and normal cells was measured using a quantitative real-time polymerase chain reaction. The effects of miR-647 expression on glioma cell proliferation, cell apoptosis, colony formation and cell invasion were measured using a cell counting kit-8 assay, flow cytometry, a colony formation assay and a transwell invasion assay. Luciferase activity reporter and western blot assays were conducted to explore whether homeobox A9 (HOXA9) was a direct target of miR-647. RESULTS: We found that miR-647 expression was downregulated in glioma cell lines compared to the normal cell line. Overexpression of miR-647 inhibits glioma cell proliferation, colony formation and cell invasion, although it promotes apoptosis in vitro. HOXA9 was validated a direct target of miR-647 and the overexpression of HOXA9 reversed the effects of miR-647 on glioma cell behavior. CONCLUSIONS: The identification of the miR-647/HOXA9 axis will advance our understanding underlying glioma progression and provide novel therapeutic targets for glioma treatment.

MicroRNA-188 aggravates contrast-induced apoptosis by targeting SRSF7 in novel isotonic contrast-induced acute kidney injury rat models and renal tubular epithelial cells.

BACKGROUND: Contrast media (CM) is widely used in cardiac catheterization; however, it may cause contrast-induced acute kidney injury (CI-AKI) which severely increases mortality. MicroRNA (miRNA) has been found to participate in the process of acute kidney injury (AKI), and this discovery has great potential for diagnosis and treatment. However, the role of miRNA in CI-AKI is still unclear. This study aimed to investigate the regulatory effect miRNAs exert in CI-AKI. METHODS: We established a novel, representative, isotonic CI-AKI model by using CM iodixanol, a CM which is commonly used in clinic. Next-generation sequencing and reverse transcription polymerase chain reaction (RT-qPCR) were performed to determine the expression of miRNA-188 in CI-AKI. Western blot analysis of the apoptosis regulator protein and TUNEL assay were ordered to evaluate apoptosis. Bioinformatics and double luciferin reporter gene assay were performed to predict and to confirm the interaction between microRNA-188 and SRSF7. RESULTS: The novel isotonic CI-AKI rat model we established exhibited typical characteristics of CI-AKI in serum creatinine, cystatin C, HE staining, and under electron microscope observation. Sequencing and RT-qPCR demonstrated that miRNA-188 was significantly up-regulated both in CI-AKI rat and HK-2 cell models while overexpression of miRNA-188 significantly aggravated apoptosis in CI-AKI cell models. SRSF7 was identified as a direct target gene of miRNA-188, and dual luciferase reporter assay determined the direct interaction between SRSF7 and miRNA-188. In addition, SRSF7 silencing reduced the cell viability rate of the CI-AKI cell model. CONCLUSIONS: The present study's findings indicate that miRNA-188 aggravated contrast-induced apoptosis by regulating SRSF7, which may serve as a potential drug target for CI-AKI intervention.

Clinical outcomes and predictive model of platelet reactivity to clopidogrel after acute ischemic vascular events.

BACKGROUND: High on-treatment platelet reactivity (HTPR) has been suggested as a risk factor for patients with ischemic vascular disease. We explored a predictive model of platelet reactivity to clopidogrel and the relationship with clinical outcomes. METHODS: A total of 441 patients were included. Platelet reactivity was measured by light transmittance aggregometry after receiving dual antiplatelet therapy. HTPR was defined by the consensus cutoff of maximal platelet aggregation >46% by light transmittance aggregometry. CYP2C19 loss-of-function polymorphisms were identified by DNA microarray analysis. The data were compared by binary logistic regression to find the risk factors. The primary endpoint was major adverse clinical events (MACEs), and patients were followed for a median time of 29 months. Survival curves were constructed with Kaplan-Meier estimates and compared by log-rank tests between the patients with HTPR and non-HTPR. RESULTS: The rate of HTPR was 17.2%. Logistic regression identified the following predictors of HTPR: age, therapy regimen, body mass index, diabetes history, CYP2C192, or CYP2C193 variant. The area under the curve of receiver operating characteristic for the HTPR predictive model was 0.793 (95% confidence interval: 0.738-0.848). Kaplan-Meier analysis showed that patients with HTPR had a higher incidence of MACE than those with non-HTPR (21.1% vs. 9.9%; χ = 7.572, P = 0.010). CONCLUSIONS: Our results suggest that advanced age, higher body mass index, treatment with regular dual antiplatelet therapy, diabetes, and CYP2C192 or CYP2C193 carriers are significantly associated with HTPR to clopidogrel. The predictive model of HTPR has useful discrimination and good calibration and may predict long-term MACE.

Three-dimensional brain arteriovenous malformation models for clinical use and resident training.

BACKGROUND: To fabricate three-dimensional (3D) models of brain arteriovenous malformation (bAVM) and report our experience with customized 3D printed models of patients with bAVM as an educational and clinical tool for patients, doctors, and surgical residents. METHODS: Using computerized tomography angiography (CTA) or digital subtraction angiography (DSA) images, the rapid prototyping process was completed with specialized software and "in-house" 3D printing service. Intraoperative validation of model fidelity was performed by comparing to DSA images of the same patient during the endovascular treatment process. 3D bAVM models were used for preoperative patient education and consultation, surgical planning, and resident training. RESULTS: 3D printed bAVM models were successful made. By neurosurgeons' evaluation, the printed models precisely replicated the actual bAVM structure of the same patients (n = 7, 97% concordance, range 95%-99% with average of < 2 mm variation). The use of 3D models was associated shorter time for preoperative patient education and consultation, higher acceptable of the procedure for patients and relatives, shorter time between obtaining intraoperative DSA data and the start of endovascular treatment. Thirty surgical residents from residency programs tested the bAVM models and provided feedback on their resemblance to real bAVM structures and the usefulness of printed solid model as an educational tool. CONCLUSIONS: Patient-specific 3D printed models of bAVM can be constructed with high fidelity. 3D printed bAVM models were proven to be helpful in preoperative patient consultation, surgical planning, and resident training.

Development of three-dimensional brain arteriovenous malformation model for patient communication and young neurosurgeon education.

PURPOSE: Rapid prototyping technology is used to fabricate three-dimensional (3D) brain arteriovenous malformation (AVM) models and facilitate presurgical patient communication and medical education for young surgeons. METHODS: Two intracranial AVM cases were selected for this study. Using 3D CT angiography or 3D rotational angiography images, the brain AVM models were reconstructed on personal computer and the rapid prototyping process was completed using a 3D printer. The size and morphology of the models were compared to brain digital subtraction arteriography of the same patients. 3D brain AVM models were used for preoperative patient communication and young neurosurgeon education. RESULTS: Two brain AVM models were successfully produced. By neurosurgeons' evaluation, the printed models have high fidelity with the actual brain AVM structures of the patients. The patient responded positively toward the brain AVM model specific to himself. Twenty surgical residents from residency programs tested the brain AVM models and provided positive feedback on their usefulness as educational tool and resemblance to real brain AVM structures. CONCLUSIONS: Patient-specific 3D printed models of brain AVM can be constructed with high fidelity. 3D printed brain AVM models are proved to be helpful in preoperative patient consultation, surgical planning and resident training.

Embolizing intracranial arteriovenous malformations with Onyx: experience at a single center with 250 patients.

Objective The aim of this study is to evaluate the embolization techniques, as well as the effects and complications, using the non-adhesive liquid embolic material Onyx in intracranial arteriovenous malformations (AVMs). Methods The study comprises a retrospective analysis of 250 patients with intracranial AVMs treated with Onyx in Guangdong General Hospital from Jan 2010 to Dec 2017. The therapeutic strategies, as well as embolization effects and complications, of Onyx are summarized. Results Of 250 cases, 170 were male and 80 were female. Following the Spetzler-Martin (S-M) grading system, there were 35 cases of grade I, 77 of grade II, 72 of grade III, 39 of grade IV, and 27 of grade V. All cases were treated with Onyx. In addition, 69 cases were treated with Glubran glue. The injected volume of Onyx per patient ranged from 1 mL to 10 mL. The largest volume of Onyx injected in one procedure was 10 mL. The cure rate was 67.9% (76/112) of grade I-II patients, 15.0% (11/72) of grade III patients, 7.7% (3/39) of grade IV patients, and 0% (0/27) of grade V patients. The total cure rate was 36.0% (90/250). The average number of targeted vascular branches per patient was 2.28. The microcatheter broke off in two cases. There were two patients who suffered an intracranial hemorrhage during the embolic procedure; in one of these two patients, the microcatheter also broke off. There were two patients who suffered an intracranial hemorrhage after the embolic procedure; one of them died. Seven cases suffered new-onset neurological deficits or their original symptoms deteriorated. Six of them improved or recovered within 3-6 months. The total complication rate was 5.2% (13/250). Conclusion The application of Onyx in intracranial AVMs is flexible, effective and safe, and may also reduce the complications.

Analysis of the Expression of Angioarchitecture-related Factors in Patients with Cerebral Arteriovenous Malformation.

BACKGROUND: Cerebral arteriovenous malformation (cAVM) is a type of vascular malformation associated with vascular remodeling, hemodynamic imbalance, and inflammation. We detected four angioarchitecture-related cytokines to make a better understanding of the potential aberrant signaling in the pathogenesis of cAVM and found useful proteins in predicting the risk of cerebral hemorrhage. METHODS: Immunohistochemical analysis was conducted on specimens from twenty patients with cAVM diagnosed via magnetic resonance imaging and digital subtraction angiography and twenty primary epilepsy controls using antibodies against vascular endothelial growth factor receptor-2 (VEGFR-2), matrix metalloproteinase-9 (MMP-9), vascular cell adhesion molecule (VCAM-1), and endothelial nitric oxide synthase (eNOS). Western blotting and real-time fluorescent quantitative polymerase chain reaction (PCR) were performed to determine protein and mRNA expression levels. Student's t-test was used for statistical analysis. RESULTS: VEGFR-2, MMP-9, VCAM-1, and eNOS expression levels increased in patients with cAVM compared with those in normal cerebral vascular tissue, as determined by immunohistochemical analysis. In addition, Western blotting and real-time PCR showed that the protein and mRNA expression levels of VEGFR-2, MMP-9, VCAM-1, and eNOS were higher in the cAVM group than in the control group, all the differences mentioned were statistically significant (P < 0.05). CONCLUSIONS: VEGFR-2, MMP-9, VCAM-1, and eNOS are upregulated in patients with cAVM and might play important roles in angiogenesis, vascular remodeling, and migration in patients with cAVM. MMP-9, VEGFR-2, VCAM-1, and eNOS might be potential excellent group proteins in predicting the risk of cerebral hemorrhage at arteriovenous malformation.

Characterizing nanoscale changes in the activity of VEGFR-2 on glioma microvascular endothelial cell membranes using atomic force microscopy.

The aim of the current study was to demonstrate the distribution of VEGFR-2 on glioma microvascular endothelial cells on a nanoscale and investigate changes in VEGFR-2 activity following treatment with the VEGFR-2 inhibitor and agonist sorafenib and bradykinin, respectively. Three groups were evaluated in this study: Control glioma microvascular endothelial cells, sorafenib-treated glioma microvascular endothelial cells and bradykinin-treated glioma microvascular endothelial cells. Changes in the activity of VEGFR-2 on the glioma microvascular endothelial cell membranes following treatment with sorafenib and bradykinin were characterized by atomic force microscopy (AFM). Colloidal gold-labeled immune complexes and AFM were used to visualize the distribution of VEGFR-2 on the cell membranes. In the control group, VEGFR-2, which was observed as numerous globular structures, was evenly distributed on the cell surface membranes. The majority of the receptors were active. In the sorafenib group, only a few globular structures were observed on the cell membranes, with a density significantly lower than that in the control group (P<0.01). Furthermore, compared with the control group, fewer of the receptors were active. In the bradykinin group, numerous globular structures were densely distributed on the cell membranes, with a density significantly higher than that in the control group (P<0.01). The distribution and activity of VEGFR-2 on glioma microvascular endothelial cell membranes treated with sorafenib and bradykinin suggested that the activity of VEGFR-2 could be regulated by its inhibitor or agonist.

Brain abscess after endosaccular embolisation of a cerebral aneurysm.

Endovascular embolization has become an important treatment option for cerebral aneurysms, along with surgical clipping. But few literatures mentioned infectious complications after coiling of aneurysms. We present a patient with a brain abscess that developed after endosaccular embolization of a left middle cerebral artery aneurysm. The brain abscess was located adjacent to the aneurysm and discovered more than 2 months after embolization. We discuss the clinical implications of this rare complication and review the literature for infections related to the coils used for embolization of aneurysms.

Macrophage migration inhibitory factor reduces apoptosis in cerebral arteriovenous malformations.

PURPOSE: To investigate the expression of macrophage migration inhibitory factor (MIF) in human brain arteriovenous malformations (AVM). MATERIALS AND METHODS: Twelve AVM specimens were obtained from patients who did not received preoperative embolization. MIF levels were measured by Western blot and matrix metalloproteinase 9 (MMP9) levels were measured by reverse transcription PCR. The expression of MIF in brain AVMs was also evaluated by immunohistochemistry and was correlated with apoptosis and the expression of cleaved caspase-3 and MMP9. RESULTS: The expression of MIF, MMP9, and cleaved caspase-3 was elevated in brain AVM vessels. High levels of MIF were primarily found in the endothelium and adventitia, whereas apoptotic cells were concentrated in the smooth muscle layer. CONCLUSIONS: Abnormal apoptosis may be involved in the pathogenesis of brain AVM. In addition, increased MIF expression could play an important role regulating the homeostasis of AVM vessels.

A study of the distribution and density of the VEGFR-2 receptor on glioma microvascular endothelial cell membranes.

The purpose of the study was to examine the nanoscale distribution and density of the VEGFR-2 membrane receptor on the endothelial cell surface of glioma microvasculature. Immunofluorescence and atomic force microscopy combined with immunogold labeling techniques were used to characterize and determine the position of the glioma microvasculature endothelial cell surface receptor VEGFR-2. We aimed to indirectly detect the distribution of VEGFR-2 on the cell membrane at the nanoscale level and to analyze VEGFR-2 quantitatively. Immunofluorescence imaging showed a large amount of VEGFR-2 scattered across the endothelial cell surface; atomic force microscopy imaging also showed two globular structures of different sizes scattered across the endothelial cell surface. The difference between the average diameter of the small globular structure outside the cell surface (43.67 ± 5.02 nm) and that of IgG (44.61 ± 3.19 nm) was not statistically significant (P > 0.05). The three-dimensional morphologies of the small globular structure outside the cell surface and IgG were similar. The difference between the average diameter of the large globular structure outside the cell surface (74.19 ± 9.10 nm) and that of IgG-SpA-CG (74.54 ± 15.93 nm) was also not statistically significant (P > 0.05). The three-dimensional morphologies of this large globular structure outside the cell surface and IgG-SpA-CG were similar. The total density of these two globular structures within the unit area was 92 ± 19 particles µm(2). No globular structures were seen on the cell surface in the control group. The large globular structure on the surface of glioma microvascular endothelial cells was categorized as a VEGFR-2-IgG-SpA-CG immune complex, whereas the small globular structure was categorized as a VEGFR-2-IgG immune complex. The positions of the globular structures were the same as the positions of the VEGFR-2 molecules. A large amount of VEGFR-2 was scattered across glioma microvascular endothelial cell surfaces; the receptor density was about 92 per square micron.