Tumor Vessels Research Articles

Efficacy of Cisplatin-CXCR4 Antagonist Combination Therapy in Oral Cancer.

Cisplatin is a platinum-based compound that is widely used for treating inoperable oral squamous cell carcinoma (OSCC) in Japan; however, resistance to cisplatin presents a challenge and innovative approaches are required. We aimed to investigate the therapeutic potential of targeting the chemokine receptor CXCR4, which is involved in angiogenesis and tumor progression, using the CXCR4 inhibitor AMD3100, in combination with cisplatin. AMD3100 induced necrosis and bleeding in OSCC xenografts by inhibiting angiogenesis. We investigated the combined ability of AMD3100 plus cisplatin to enhance the antitumor effect in cisplatin-resistant OSCC. An MTS assay identified HSC-2 cells as cisplatin-resistant cells in vitro. Mice treated with the cisplatin-AMD combination exhibited the most significant reduction in tumor volume, accompanied by extensive hemorrhage and necrosis. Histological examination indicated thin and short tumor vessels in the AMD and cisplatin-AMD groups. These results indicated that cisplatin and AMD3100 had synergistic antitumor effects, highlighting their potential for vascular therapy of refractory OSCC. Antitumor vascular therapy using cisplatin combined with a CXCR4 inhibitor provides a novel strategy for addressing cisplatin-resistant OSCC.

Probabilistic Nested Model Selection in Pharmacokinetic Analysis of DCE-MRI Data in Animal Model of Cerebral Tumor.

Best current practice in the analysis of dynamic contrast enhanced (DCE)-MRI is to employ a voxel-by-voxel model selection from a hierarchy of nested models. This nested model selection (NMS) assumes that the observed time-trace of contrast-agent (CA) concentration within a voxel, corresponds to a singular physiologically nested model. However, admixtures of different models may exist within a voxel's CA time-trace. This study introduces an unsupervised feature engineering technique (Kohonen-Self-Organizing-Map (K-SOM)) to estimate the voxel-wise probability of each nested model. Sixty-six immune-compromised-RNU rats were implanted with human U-251N cancer cells, and DCE-MRI data were acquired from all the rat brains. The time-trace of change in the longitudinalrelaxivity for all animals' brain voxels was calculated. DCE-MRI pharmacokinetic (PK) analysis was performed using NMS to estimate three model regions: Model-1: normal vasculature without leakage, Model-2: tumor tissues with leakage without back-flux to the vasculature, Model-3: tumor vessels with leakage and back-flux. Approximately two hundred thirty thousand (229,314) normalized profiles of animals' brain voxels along with their NMS results were used to build a K-SOM (topology-size: 8×8, with competitive-learning algorithm) and probability map of each model. K-fold nested-cross-validation (NCV, k=10) was used to evaluate the performance of the K-SOM probabilistic-NMS (PNMS) technique against the NMS technique. The K-SOM PNMS's estimation for the leaky tumor regions were strongly similar (Dice-Similarity-Coefficient, DSC=0.774 [CI: 0.731-0.823], and 0.866 [CI: 0.828-0.912] for Models 2 and 3, respectively) to their respective NMS regions. The mean-percent-differences (MPDs, NCV, k=10) for the estimated permeability parameters by the two techniques were: -28%, +18%, and +24%, for , and , respectively. The KSOM-PNMS technique produced microvasculature parameters and NMS regions less impacted by the arterial-input-function dispersion effect. This study introduces an unsupervised model-averaging technique (K-SOM) to estimate the contribution of different nested-models in PK analysis and provides a faster estimate of permeability parameters.

Role of transforming growth factor-β1 pathway in angiogenesis induced by chronic stress in colorectal cancer

ABSTRACT Background Chronic stress can induce stress-related hormones; norepinephrine (NE) is considered to have the highest potential in cancer. NE can stimulate the expression of hypoxia-inducible factor-1α (HIF-1α), which is associated with vascular endothelial growth factor (VEGF) secretion and tumor angiogenesis. However, the underlying mechanisms are poorly understood. Methods Tumor-bearing mice were subjected to chronic restraint stress and treated with normal saline, human monoclonal VEGF-A neutralizing antibody bevacizumab, or β-adrenergic receptor (β-AR) antagonist (propranolol). Tumor growth and vessel density were also evaluated. Human colorectal adenocarcinoma cells were treated with NE, propranolol, or the inhibitor of transforming growth factor-β (TGF-β) receptor Type I kinase (Ly2157299) in vitro. TGF-β1 in mouse serum and cell culture supernatants was quantified using ELISA. The expression of HIF-1α was measured using Real time-PCR and western blotting. Cell migration and invasion were tested. Results Chronic restraint stress attenuated the efficacy of bevacizumab and promoted tumor growth and angiogenesis in a colorectal tumor model. Propranolol blocked this effect and inhibited TGF-β1 elevation caused by chronic restraint stress or NE. NE upregulated HIF-1α expression, which was reversed by propranolol or Ly2157299. Propranolol and Ly2157199 blocked NE-stimulated cancer cell migration and invasion. Conclusions Our results demonstrate the effect of NE on tumor angiogenesis and the critical role of TGF-β1 signaling during this process. In addition, β-AR/TGF-β1 signaling/HIF-1α/VEGF is a potential signaling pathway. This study also indicates that psychosocial stress might be a risk factor which weakens the efficacy of anti-angiogenic therapy.

High CIB1 expression in colorectal cancer liver metastases correlates with worse survival and the replacement histopathological growth pattern

To date, nearly one-quarter of CRC patients develop liver metastases (CRCLM), and its aggressiveness can be correlated to defined histopathological growth patterns (HGP). From the three main HGPs within CRCLM, the replacement HGP emerges as particularly aggressive, characterized by heightened tumor cell motility and vessel co-option. Here, we investigated the correlation between the expression of CIB1, an ubiquitously expressed gene involved in various cellular processes including migration and adhesion, and disease-free (DFS) and overall survival (OS) in primary CRC patients. Additionally, we explored the correlation between CIB1 expression and different HGP of CRCLM. Proteomic analysis was used to evaluate CIB1 expression in a cohort of 697 primary CRC patients. Additionally, single-cell and spatial RNA-sequencing datasets, along with a publicly available bulk sequencing data were used to evaluate CIB1 expression in CRCLM. In silico data was further validate by FFPE immunohistochemical stainings. We observed that high CIB1 expression is independently associated with worse DFS and OS, regardless of UICC stage, gender, or age. Furthermore, the aggressive replacement CRCLM HGP is significantly associated with high CIB1 expression. Our findings show a correlation between CIB1 levels and the clinical aggressiveness of CRC. Moreover, CIB1 may be a novel marker to stratify HGP CRCLM.

Swept-source optical coherence tomography and swept-source optical coherence tomography angiography findings in circumscribed choroidal hemangioma before and after transpupillary thermotherapy

PurposeTo investigate the swept-source optical coherence tomography (SS-OCT) and SS-OCT angiography (SS-OCTA) findings in circumscribed choroidal hemangioma (CCH) before and after treatment with transpupillary thermotherapy (TTT).MethodsThe clinical records of 21 eyes having CCH imaged with SS-OCT/SS-OCTA between September 2018 and December 2022 were evaluated.ResultsSS-OCT examination in CCH showed dome-shaped appearance (100%), choroidal shadowing (100%), expansion of choroidal structures (100%), subretinal fluid (66.7%), intraretinal edema/schisis (33.3%), retinal pigment epithelium (RPE) atrophy (19.0%), hyperreflective dots (19.0%), and epiretinal membrane (4.8%). Internal arborizing tumor vessels showing hyperreflectivity were observed in the choriocapillaris slab on SS-OCTA in all eyes. In the deep capillary plexus (DCP), flow void changes were seen in 7 eyes with intraretinal schisis/cystoid macular edema. Four CCHs > 2 mm in thickness showed outer retinal involvement due to unmasking of flow in intratumoral vessels related to RPE atrophy. Following TTT/indocyanine green-enhanced TTT (ICG-TTT) of CCH, SS-OCT findings included total/partial resolution of subretinal fluid (57.1%), complete/partial regression of the tumor (52.4%), and RPE atrophy (33.3%). After treatment; loss of choriocapillaris, decrease in tumor vascularity together with increase in the fibrous component and flow void areas were detected on SS-OCTA.ConclusionsSS-OCT/SS-OCTA are useful non-invasive tools for imaging the structural/vascular changes in CCHs managed with TTT or ICG-TTT. On SS-OCTA, hyporeflective spaces localizing to edema/schisis in the DCP and arborizing tumor vessels within a hyporeflective stromal background in the choriocapillaris slab were observed. After TTT/ICG-TTT, a decrease in tumor vessels and an increase in the fibrous component and flow-void areas inside the CCH were detected on SS-OCTA.

Disturbance in cerebral blood microcirculation and hypoxic-ischemic microenvironment are associated with the development of brain metastasis.

Brain metastases (BM) constitute an increasing challenge in oncology due to their impact on neurological function, limited treatment options, and poor prognosis. BM occurs through extravasation of circulating tumor cells across the blood-brain barrier. However, the extravasation processes are still poorly understood. We here propose a brain colonization process which mimics infarction-like microenvironmental reactions, that are dependent on Angiopoietin-2 (Ang-2) and vascular endothelial growth factor (VEGF). In this study, intracardiac BM models were used, and cerebral blood microcirculation was monitored by 2-photon microscopy through a cranial window. BM formation was observed using cranial magnetic resonance, bioluminescent imaging, and postmortem autopsy. Ang-2/VEGF targeting strategies and Ang-2 gain-of-function (GOF) mice were employed to interfere with BM formation. In addition, vascular and stromal factors as well as clinical outcomes were analyzed in BM patients. Blood vessel occlusions by cancer cells were detected, accompanied by significant disturbances of cerebral blood microcirculation, and focal stroke-like histological signs. Cerebral endothelial cells showed an elevated Ang-2 expression both in mouse and human BM. Ang-2 GOF resulted in an increased BM burden. Combined anti-Ang-2/anti-VEGF therapy led to a decrease in brain metastasis size and number. Ang-2 expression in tumor vessels of established human BM negatively correlated with survival. Our observations revealed a relationship between disturbance of cerebral blood microcirculation and brain metastasis formation. This suggests that vessel occlusion by tumor cells facilitates brain metastatic extravasation and seeding, while combined inhibition of microenvironmental effects of Ang-2 and VEGF prevents the outgrowth of macrometastases.

Association of combination tumor texture and vessel tortuosity with progression free survival across PD-L1 subgroups in durvalumab treated non-small cell lung cancer (NSCLC): Blinded validation results from CP1108.

8600 Background: Immunotherapy (IO) has shown a durable response with minimal toxicity in the treatment of metastatic NSCLC. However, only 30-50% of these patients (pts) actually respond. Despite initial optimism surrounding PD-L1 expression as a potential biomarker, IO provides benefit across PD-L1 low (<25%) and high (≥25%) status. This highlights a critical need for more effective biomarkers to guide treatment decisions. Here, we present blinded validation results of a CT-based biomarker of change in quantitative vessel tortuosity (1) (Δ-QVT) and texture radiomics (2) (Δ-Rad) between baseline (B) and 6 weeks post-treatment (TP1) for predicting response, overall survival (OS) and progression free survival (PFS) in CP1108 (NCT01693562). Methods: CT scans at B and TP1 were retrospectively analyzed from two studies (a) a multi-center training set (Str, N=110) of metastatic NSCLC pts treated with first line IO and (b) a blinded NSCLC cohort of N = 151 pts treated with Durvalumab in CP1108 study (Sv). In Sv, N=75 pts were PD-L1 high (Sv+) whereas N=65 pts were PD-L1 low (Sv-). An in-house MATLAB based algorithm was used to extract intra-tumoral, peri-tumoral texture and QVT features from up to two largest measurable tumors in each CT. A classifier (MCombo) was trained on Str to predict best overall response defined as per the RECIST v1.1 criteria using combination of Δ-QVT and Δ-Rad features. Area under the receiver operating characteristic (AUC) was used to evaluate MCombo against RECIST response whereas univariable and multivariable Cox regression models with log-rank test, hazard ratio (HR) with confidence interval (CI) and concordance index (C-index) were used to study the association of MCombo with OS and PFS in Sv, Sv+, and Sv-. Results: MCombo predicted objective response with an AUC of 0.78 in Sv and was statistically significantly associated with PFS (Table) in Sv, Sv+, and Sv-. MCombo was associated with OS in Sv, Sv+, but not in Sv-. Multivariable analysis with PD-L1 status, histological subtype, ECOG status, liver metastasis, line of therapy and sex showed independent association of MCombo across OS and PFS. Conclusions: Our results indicate that combination of radiomics and vessel tortuosity biomarker from CT is independently prognostic of response and PFS across PD-L1 levels. Prospective validation of this biomarker is needed. 1. Alilou et al. Sci Adv 2022. 2. Khorrami et al. Cancer Immunol Res 2020. [Table: see text]

Are we ready to use PSMA as a theranostic biomarker in clinical practice for patients with breast cancer?

e13114 Background: Subtype classification for breast cancer (BC) patients is important for risk-stratification. Unfortunately, this parameter is not able to discriminate perfectly between high- and low-risk disease and the identification of an accurate biomarker to determine aggressiveness is still a clinical need. Prostate-specific membrane antigen (PSMA) could be important given that it has been reported to be expressed in BC tumor cells and even more in endothelial cells of tumor vessels. Methods: We analyzed 101 BCs of whom 22 luminal A, 34 Luminal B, 22 HER2 positive and 23 triple negative (TN) BC to assess whether PSMA expression by immunohistochemistry was different in tumor subtypes and was related to ki67 expression and stromal (tumour-infiltrating lymphocytes) TILs. PSMA positivity was calculated as the number of positive vessels on 10 fields at 40X magnifications. Kruskal Wallis’s test was used to assess difference in PSMA positivity among BC subgroups and Dunn’s test was performed for post-hoc comparisons; Spearman’s rho coefficient was calculated to analyze the correlation among PSMA, KI67 and TILs. Results: The median age at diagnosis of BC patients was 66 (min-max: 25-87 years). Seventy (69.3%) patients had ER>0 and 64 (63.4%) had PgR>0. The ductal histotype was present in 92 patients (91%). The majority of the patients had grade 3 tumors (55.4%). Considering the number of positive vessels, our results showed that median PSMA was higher in TNBC compared to Luminal A, Luminal B and HER2 positive tumors (p<0.001, p=0.001 and p=0.041, respectively). Ki67 was higher in TNBC compared to Luminal A, Luminal B and HER2 positive tumors (p<0.001, p<0.001 and p=0.001, respectively). We saw a correlation between PSMA and ki67, especially in HER2 positive tumors (p<0.001), while a correlation between PSMA and TILs was observed in Luminal A (p=0.028). The analysis of PSMA expression on the lymph nodes showed the same trend observed for the primary tumors given that it was higher in TNBC compared to HER2 positive and luminal cancers. Conclusions: Our results suggest that PSMA could be used as a theranostic biomarker in BC considering that it is highly expressed in more aggressive tumors and the possibility to treat PSMA expressing patients for anti-angiogenesis and/or radionuclide treatment.

Different types of tumor microvessels in stage I-IIIA squamous cell lung cancer and their clinical significance.

Lung cancer (LC) is the leading cause of morbidity and mortality among malignant neoplasms. Improving the diagnosis and treatment of LC remains an urgent task of modern oncology. Previously, we established that in gastric, breast and cervical cancer, tumor microvessels (MVs) differ in morphology and have different prognostic significance. The connection between different types of tumor MVs and the progression of LC is not well understood. To evaluate the morphological features and clinical significance of tumor MVs in lung squamous cell carcinoma (LUSC). A single-center retrospective cohort study examined medical records and archival paraffin blocks of 62 and 180 patients with stage I-IIIA LUSC in the training and main cohorts, respectively. All patients underwent radical surgery (R0) at the Orenburg Regional Cancer Clinic from May/20/2009 to December/14/2021. Tumor sections were routinely processed, and routine Mayer's hematoxylin and eosin staining and immunohistochemical staining for cluster of differentiation 34 (CD34), podoplanin, Snail and hypoxia-inducible factor-1 alpha were performed. The morphological features of different types of tumor MVs, tumor parenchyma and stroma were studied according to clinicopathological characteristics and LUSC prognosis. Statistical analysis was performed using Statistica 10.0 software. Univariate and multivariate logistic regression analyses were performed to identify potential risk factors for LUSC metastasis to regional lymph nodes (RLNs) and disease recurrence. Receiver operating characteristic curves were constructed to discriminate between patients with and without metastases in RLNs and those with and without disease recurrence. The effectiveness of the predictive models was assessed by the area under the curve. Survival was analyzed using the Kaplan-Meier method. The log-rank test was used to compare survival curves between patient subgroups. A value of P < 0.05 was considered to indicate statistical significance. Depending on the morphology, we classified tumor vessels into the following types: normal MVs, dilated capillaries (DCs), atypical DCs, DCs with weak expression of CD34, "contact-type" DCs, structures with partial endothelial linings, capillaries in the tumor solid component and lymphatic vessels in lymphoid and polymorphocellular infiltrates. We also evaluated the presence of loose, fine fibrous connective tissue (LFFCT) and retraction clefts in the tumor stroma, tumor spread into the alveolar air spaces (AASs) and fragmentation of the tumor solid component. According to multivariate analysis, the independent predictors of LUSC metastasis in RLNs were central tumor location (P < 0.00001), the presence of retraction clefts (P = 0.003), capillaries in the tumor solid component (P = 0.023) and fragmentation in the tumor solid component (P = 0.009), whereas the independent predictors of LUSC recurrence were tumor grade 3 (G3) (P = 0.001), stage N2 (P = 0.016), the presence of LFFCT in the tumor stroma (P < 0.00001), fragmentation of the tumor solid component (P = 0.0001), and the absence of tumor spread through the AASs (P = 0.0083). The results obtained confirm the correctness of our previously proposed classification of different types of tumor vessels and may contribute to improving the diagnosis and treatment of LUSC.

Effect of novel anti-tumor and anti-angiogenesis drug taurolactone on angiogenic factor AGGF1 and angiogenesis mimicry in patients with hepatocellular carcinoma

ObjectiveOur study was to investigate the impact of taurolactone, a novel anti-tumor and anti-angiogenic drug, on AGGF1, an angiogenic factor, and angiogenesis mimicry in patients diagnosed with hepatocellular carcinoma (HCC).MethodsA total of 120 HCC patients were enrolled from the Department of Oncology and Hepatobiliary Surgery at our hospital between May 2021 and December 2022. HCC diagnoses were confirmed through imaging or tissue biopsy for all patients. The age of patients ranged from 37 to 72 years, with an average age of 64.29 ± 4.58 years. These participants were divided equally into two groups: the control group and the observation group, each consisting of 60 individuals. While the control group received standard drug treatment, the observation group was administered taurolactone treatment. Before being included in the study, all participants or their legal representatives provided signed informed consent. Patient demographic information was collected through a questionnaire survey. ELISA was used to measure the levels of VEGF and AGGF1 in patients following treatment. Western blot was applied to assess the protein expression of PDGF, Angiopoietin, and AGGF1. MRI imaging technology was utilized to assess the perfusion characteristics of tumor blood vessels in patients. Tumor vessel density was compared between patients using ultrasonography. We also conducted a comparison between the two groups in terms of progression-free survival and overall survival.ResultsGeneral patient information between the two groups showed no significant differences (P > 0.05). Of note, the observation group exhibited greatly lower levels of VEGF and AGGF1 compared to the control group (P < 0.05). Moreover, the levels of PDGF, Angiopoietin, and AGGF1 protein expression were significantly reduced in the observation group compared to the control group (P < 0.05). In terms of tumor perfusion, the observation group displayed lower average and maximum perfusion volumes in tumor blood vessels compared to the control group (P < 0.05). Additionally, the observation group demonstrated delayed peak times and arrival times of tumor blood vessels in comparison to the control group (P < 0.05). Furthermore, the density of tumor blood vessels was notably lower in the observation group compared to the control group (P < 0.05). Patients in the observation group had longer progression-free survival and overall survival than the control group (P < 0.05).ConclusionIn HCC patients, our study highlighted the potential efficacy of taurolactone treatment as it effectively inhibited angiogenic factors and angiogenesis mimicry, ultimately leading to an improved prognosis for these patients.

Prostate-Specific Membrane Antigen Targeted StarPEG Nanocarrier for Imaging and Therapy of Prostate Cancer.

The tumor uptake of large non-targeted nanocarriers primarily occurs through passive extravasation, known as the enhanced permeability and retention (EPR) effect. Prior studies demonstrated improved tumor uptake and retention of 4-arm 40 kDa star polyethylene glycol (StarPEG) polymers for cancer imaging by adding prostate-specific membrane antigen (PSMA) targeting small molecule ligands. To test PSMA-targeted delivery and therapeutic efficacy, StarPEG nanodrugs with/without three copies of PSMA-targeting ligands, ACUPA, are designed and synthesized. For single-photon emission computed tomography (SPECT) imaging and therapy, each nanocarrier is labeled with 177Lu using DOTA radiometal chelator. The radiolabeled nanodrugs, [177Lu]PEG-(DOTA)1 and [177Lu]PEG-(DOTA)1(ACUPA)3, are evaluated in vitro and in vivo using PSMA+ PC3-Pip and/or PSMA- PC3-Flu cell lines, subcutaneous xenografts and disseminated metastatic models. The nanocarriers are efficiently radiolabeled with 177Lu with molar activities 10.8-15.8 MBq/nmol. Besides excellent in vitro PSMA binding affinity (kD = 51.7nM), the targeted nanocarrier, [177Lu]PEG-(DOTA)1(ACUPA)3, demonstrated excellent in vivo SPECT imaging contrast with 21.3% ID/g PC3-Pip tumors uptake at 192h. Single doses of 18.5MBq [177Lu]PEG-(DOTA)1(ACUPA)3 showed complete resolution of the PC3-Pip xenografts observed up to 138days. Along with PSMA-targeted excellent imaging contrast, these results demonstrated high treatment efficacy of [177Lu]PEG-(DOTA)1(ACUPA)3 for prostate cancer, with potential for clinical translation.

Prostate-Specific Membrane Antigen Positron Emission Tomography Oncological Applications beyond Prostate Cancer in Comparison to Other Radiopharmaceuticals.

Prostate-specific membrane antigen (PSMA) is a type II transmembrane glycoprotein overexpressed on the surface of tumor cells in most of the patients affected by prostate adenocarcinoma (PCa). However, PSMA expression has also been demonstrated in the endothelial cells of newly formed vessels of various solid tumors, suggesting a role for PSMA in neoangiogenesis. In this scenario, gallium-68 (68Ga) or fluoro-18 (18F)-labeled PSMA positron emission tomography (PET) may play a role in tumors other than PCa, generally evaluated employing other radiopharmaceuticals targeting different pathways. This review aims to investigate the detection rate of PSMA-PET compared to other radiopharmaceuticals (especially [18F]FDG) in non-prostate tumors to identify patients who may benefit from the use of such a theragnostic agent. We performed a bibliographic search on three different databases until February 2024 using the following terms: "positron emission tomography", "PET", "PET/CT", "Prostate-specific membrane antigen", "PSMA", "non-prostate", "not prostate cancer", "solid tumor", "FDG", "Fluorodeoxyglucose", "FAPi", "FET", "MET", "DOPA", "choline", "FCH", "FES", "DOTATOC", "DOTANOC", and "DOTATATE". Only original articles edited in English with at least 10 patients were included. Out of a total of 120 articles, only 25 original articles comparing PSMA with other radiotracers were included in this study. The main evidence was demonstrated in renal cell carcinoma, where PSMA showed a higher detection rate compared to [18F]FDG PET/CT, with implications for patient management. PSMA PET may also improve the assessment of other entities, such as gliomas, in defining regions of early neoangiogenesis. Further data are needed to evaluate the potential role of PSMA-PET in triple-negative breast cancer as a novel therapeutic vascular target. Finally, unclear applications of PSMA-PET include thyroid and gastrointestinal tumors. The present review shows the potential use of PSMA-labeled PET/CT in solid tumors beyond PCa, underlining its value over other radiopharmaceuticals (mainly [18F]FDG). Prospective clinical trials with larger sample sizes are crucial to further investigate these possible clinical applications.

Photodynamically Tumor Vessel Destruction Amplified Tumor Targeting of Nanoparticles for Efficient Chemotherapy.

Efficient tumor-targeted drug delivery is still a challenging and currently unbreakable bottleneck in chemotherapy for tumors. Nanomedicines based on passive or active targeting strategy have not yet achieved convincing chemotherapeutic benefits in the clinic due to the tumor heterogeneity. Inspired by the efficient inflammatory-cell recruitment to acute clots, we constructed a two-component nanosystem, which is composed of an RGD-modified pyropheophorbide-a (Ppa) micelle (PPRM) that mediates the tumor vascular-targeted photodynamic reaction to activate local coagulation and subsequently transmits the coagulation signals to the circulating clot-targeted CREKA peptide-modified camptothecin (CPT)-loaded nanodiscs (CCNDs) for amplifying tumor targeting. PPRM could effectively bind with the tumor vasculature and induce sufficient local thrombus by a photodynamic reaction. Local photodynamic reaction-induced tumor target amplification greatly increased the tumor accumulation of CCND by 4.2 times, thus significantly enhancing the chemotherapeutic efficacy in the 4T1 breast tumor model. In other words, this study provides a powerful platform to amplify tumor-specific drug delivery by taking advantage of the efficient crosstalk between the PPRM-activated coagulation cascade and clot-targeted CCND.

Abstract PO2-15-09: Immune related cell fraction in peripheral blood and outcomes of advanced breast cancer patients treated with Eribulin

Abstract Background: Eribulin prolongs overall survival (OS) of patients with advanced breast cancer, and an ad-hoc analysis of the EMBRACE trial showed that baseline absolute lymphocyte count (ALC) was a predictor of OS prolongation. It has been suggested that eribulin improves the immune response to the tumor by improving the hypoxic environment through remodeling of local tumor vessels and reducing hypoxic stress, leading to OS prolongation. However, the details of the immune response mediated by eribulin remain to be fully elucidated. CD8+ cells attack cancer cells as cytotoxic T cells, while regulatory T cells (Tregs) and myeloid-derived suppressor cells (MDSCs) suppress activated T cells that attack cancer cells. In this study, we focused on CD8+ cytotoxic T cells, Tregs, MDSCs, and CD4-CD25-FoxP3+ cells in peripheral blood, analyzed the changes of those immune cells before and after eribulin treatment, and examined the effects on the outcomes of breast cancer patients. Methods: Nineteen patients with advanced or recurrent breast cancer treated with eribulin from April 2021 to May 2023 at our hospital were included. Peripheral blood was collected before drug administration as the first treatment (pre-treatment) and before drug administration in the second course (post-treatment), and the cell fractions, including CD4+ cells, CD8+ cells, CD4+CD25+FoxP3+ Tregs, CD11b+CD14+CD33+ MDSCs, and CD4-CD25-FoxP3+ cells, were analyzed by flow cytometry. The cutoff value for ALC was set at 1000 and NLR at 3.0, and each cell fraction was set to its respective median. Kaplan-Meier plots and logrank tests for progression-free survival (PFS) or OS were applied. Results: CD4+ cells were significantly lower post-treatment compared to pre-treatment (p=0.0140). Further, Tregs were significantly lower post-treatment compared to pre-treatment (p=0.0258). There were no significant changes in the levels of CD8+ cells, MDSCs, and CD4-CD25-FoxP3+ cells between pre- and post-treatment. We examined the association between each cell fraction and ALC or NLR, and found that CD4-CD25-FoxP3+ cells were significantly higher in cases with high NLR (p=0.0110). Analysis of the association between each cell fraction and prognosis at pre-treatment revealed that the high CD8+ cell group had significantly better PFS and OS than the low CD8+ cell group (p=0.0129 and p=0.0077, respectively). Interestingly, the high CD4-CD25-FoxP3+ cell group had significantly worse PFS than the low CD4-CD25-FoxP3+ cell group (p=0.0026). Conclusion: In the current study, Tregs in the peripheral blood of breast cancer patients significantly decreased after eribulin treatment, suggesting that eribulin may improve the immune microenvironment by suppressing immunosuppressive cells in cancer, including Tregs. In addition, the CD4-CD25-FoxP3+ cell fraction may serve as a biomarker for eribulin therapy, and further studies are needed to elucidate the details, including analysis of the constituent cells within the fraction. Citation Format: Masayuki Nagahashi, Ayako Bun, Mamiko Kuroiwa, Miki Komatsu, Sayaka Urano, Yukie Fujimoto, Aoi Oshiro, Ayumu Mitsuyoshi, Haruka Kanaoka, Akira Hattori, Reiko Fukui, Tomoko Higuchi, Arisa Nishimukai, Keiko Murase, Yuichi Takatsuka, Yasuo Miyoshi. Immune related cell fraction in peripheral blood and outcomes of advanced breast cancer patients treated with Eribulin [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO2-15-09.

Abstract PO4-13-05: Spotlight on PSMA as a new theranostic biomarker for breast cancer

Abstract Breast cancer patients are risk-stratified on the basis of the subtype classification. However, this parameter is not completely accurate in discriminating between high- and low-risk disease, creating a need for a reliable marker to determine aggressiveness. Prostate-specific membrane antigen (PSMA) could fulfill this need given that it has been reported to be expressed by breast cancer tumor cells and the endothelial cells of tumor vessels. We analyzed 68 breast cancers (BC) of whom 14 luminal A, 28 Luminal B, 15 HER2 positive and 11 triple negative BC to assess whether PSMA expression by immunohistochemistry was different in the several tumor subtypes and was related to ki67 expression and stromal TILs. PSMA positivity was calculated as the number of positive vessels on 10 fields at 40X magnifications. Kruskal Wallis’s test was used to assess difference in PSMA positivity among BC subgroups and Dunn’s test was performed for post-hoc comparisons; Spearman’s rho coefficient was calculated to analyze the correlation among PSMA, KI67 and TILs. Our results show that median PSMA was higher both considering the number of positive vessels and the staining intensity in TNBC compared to Luminal A and B tumors (p&amp;lt; 0.001). Ki67 was higher in TNBC compared to Luminal A tumors (p&amp;lt; 0.001). We saw a correlation between PSMA and ki67, especially in HER2+ tumors (p=0.002), while a correlation between PSMA and TILs was observed in TNBC (p=0.014). The analysis of PSMA expression on the lymph nodes showed the same trend observed for the primary tumors given that it was higher in TNBC compared to HER2 positive and luminal cancers. Our results suggest that PSMA could be used as theranostic biomarker in BC considering that it is highly expressed in more aggressive tumors and the possibility to treat PSMA-expressing patients for anti-angiogenesis and/or radionuclide treatment. Citation Format: Sara Bravaccini, Stefania Cortecchia, Flavia Foca, Giovanni Martinelli, Sara Ravaioli, Maria Maddalena Tumedei, Federica Matteucci, Roberta Maltoni, Giovanni Paganelli, Francesca Poli, Maurizio Puccetti. Spotlight on PSMA as a new theranostic biomarker for breast cancer [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO4-13-05.

Predicting red blood cell traffcking and capillary hemodynamics in angiogenic and tumor microcirculation in silico

Objective: Angiogenic and tumor microvasculatures are known to have abnormal topology due to the presence of frequent vessel junctions, irregular and deflated blood vessels, multi-furcations, and tessellated vessel organization. Although recent advances in imaging techniques in vivo have enabled mapping such vasculatures at high spatial resolution, simultaneous measurements of hemodynamic parameters, such as the wall shear stress (WSS) with full 3D details, remain a challenge. Theoretical network flow models, often used for hemodynamic predictions in such experimentally acquired images, cannot provide the full 3D hemodynamic details either, as these models treat each blood vessel as 1D segment and do not explicitly model red blood cells (RBCs). To overcome this limitation, we have developed a high-fidelity, 3D Computational Fluid Dynamics modeling to predict the flow of a large number of deformable RBCs through physiologically realistic tumor/angiogenic microvascular networks in silico. Methods: We use in vivo images to create such vascular networks in silico and then predict RBC traffcking and capillary hemodynamics. Deformation of every flowing RBC is considered with high accuracy, and 3D geometry of each vessel is accurately modeled. Flow is driven by specifying physiological pressure boundary conditions. Model predictions have been validated against in vivo data. This in-house predictive tool is versatile, can be applied to any microvascular network image obtained in vivo in any organ, and can predict trajectories of diverse cell types including leukocytes, platelets and circulating tumor cells, drug and molecular transport in capillary blood, and cell-vessel adhesion. Results: We provide quantitative differences between healthy microvascular networks and tumor/angiogenic networks in terms of RBC distribution, perfusion, and wall shear stress. Our model shows increased heterogeneity in RBC and flow distribution in both tumor and angiogenic vasculatures than the healthy one. Also, we predict reduced flow and hematocrit in several vessels in both tumor and angiogenic vasculatures. Interestingly, several vessels in the angiogenic vasculature are predicted to have higher flow than the healthy one, while most vessels in the tumor vasculature show flow reduction. This in silico prediction is consistent with a recent in vivo study which showed higher flow in peri-tumor region and reduced flow in tumor. We further predict a significant heterogeneity in WSS and WSS gradient, blood velocity profiles, and near-wall RBC-depleted region. Conclusion: In conclusion, we have developed a versatile, in silico model that allows high-fidelity prediction of capillary hemodynamics in tumor microcirculation and provide information on hemodynamic variables that are not readily measurable in vivo but have physiological significance in tumor progression and treatment. NIH (R01EY033003) and NSF (CBET1804591). This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

DOES EXERCISE CHANGE BLOOD FLOW TO TUMOURS? ACUTE AEROBIC EXERCISE EFFECTS ON LIVER METASTASES BLOOD FLOW: A CASE SERIES

AIM Effective cancer treatment relies on intravenous chemotherapy penetrating the entire tumour in sufficient concentrations, which is largely reliant on effective blood supply into and within the tumour. However, tumours contain abnormal vasculature with inefficient blood perfusion leading to the inability for chemotherapy to reach the target tumour. Pre-clinical evidence suggests acute exercise may increase blood flow by 200%. However, most pre-clinical studies investigate the effects of light-to-moderate intensity exercise and subsequently there is little evidence regarding the most effective exercise intensity for improved tumour vasculature. Therefore, the aim of this ongoing case series is to determine whether exercise changes tumour blood flow in a clinical model using non-invasive techniques, and how exercise intensity effects degree of change in blood flow to tumours in patients with liver metastases. METHODS Participants were eligible if they were aged over 18 years, had stage IV cancer with liver metastasis and ECOG 0-2. The study visit consisted of an aerobic fitness test (YMCA) to determine cardiorespiratory fitness and three 5-minute bouts of exercise at low, moderate and high intensities. After each exercise bout, Doppler ultrasound was used to measure a liver tumour vessel and the hepatic artery (as a control) to determine blood flow parameters. RESULTS Exercise increased peak systolic velocities (PSV) to liver tumours at all intensities compared to rest. Moderate and high exercise intensities showed a marked increase in PSV within the first 2 minutes after exercise. The hepatic artery showed less variability in PSV with time compared to the liver tumour. Cardiorespiratory fitness did not affect tumour PSV. CONCLUSION The results of this case series thus far suggest that exercise increases tumour blood flow at all exercise intensities with particular emphasis on moderate and high intensities. This supports the potential for using exercise as an adjunct to standard treatment to improve chemotherapy efficacy.

Neuropilin-1 Binding Peptide as Fusion to Diphtheria Toxin Induces Apoptosis in Non-small Cell Lung Cancer Cell Line.

Targeted cancer therapy can be considered as a new strategy to overcome the side effects of current cancer treatments. Neuropilin-1 (NRP-1) is a transmembrane glycoprotein that is expressed in endothelial cells and tumor vessels to stimulate angiogenesis progression. Targeted diphtheria toxin (DT)- based therapeutics are promising tools for cancer treatment. This study aimed to construct a novel NRP-1 binding peptide (as three repeats) (CRGDK) as a fusion to truncated DT (DTA) (DTA-triCRGDK) for targeted delivery of DT into NRP-1 expressing cells. The concept of DTA-triCRGDK was designed, synthesized and cloned into the bacterial host. Expression of DTA-triCRGDK was induced by Isopropyl ß-D-1-thiogalactopyranoside (IPTG) and purification was performed using Ni-NTA chromatography. Biological activity of DTA-triCRGDK was evaluated using MTT, apoptosis, and wound healing assays. In addition, expression levels of apoptotic Bax, Bcl2, and Casp3 genes were determined by Real-time PCR. Cytotoxicity analysis showed the IC50 values of DTA-triCRGDK for A549 and MRC5 were 0.43 nM and 4.12 nM after 24 h, respectively. Bcl2 expression levels decreased 0.4 and 0.72 fold in A549 and MRC5, respectively. However, Bax and Casp3 expression level increased by 6.75 and 8.19 in A549 and 2.51 and 3.6 in MRC5 cells. Taken together, DTA-triCRGDK is a promising tool for targeted therapy of NRP-1 overexpressing cancer cells.

Neuropilin-1-Targeted Nanomedicine for Spatiotemporal Tumor Suppression through Photodynamic Vascular Damage and Antiangiogenesis.

Antiangiogenic therapy is an effective way to disrupt nutrient supply and starve tumors, but it is restricted by poor efficacy and negative feedback-induced tumor relapse. In this study, a neuropilin-1 (NRP-1)-targeted nanomedicine (designated as FPPT@Axi) is reported for spatiotemporal tumor suppression by combining photodynamic therapy (PDT) with antiangiogenesis. In brief, FPPT@Axi is prepared by utilizing an NRP-1-targeting chimeric peptide (Fmoc-K(PpIX)-PEG8-TKPRR) to encapsulate the antiangiogenic drug Axitinib (Axi). Importantly, the NRP-1-mediated targeting property enables FPPT@Axi to selectively concentrate at vascular endothelial and breast cancer cells, facilitating the production of reactive oxygen species (ROS) in situ for specific vascular disruption and enhanced cell apoptosis under light stimulation. Moreover, the codelivered Axi can further inhibit vascular endothelial growth factor receptor (VEGFR) to impair the negative feedback of PDT-induced tumor neovascularization. Consequently, FPPT@Axi spatiotemporally restrains the tumor growth through blocking angiogenesis, destroying tumor vessels, and inducing tumor apoptosis. Such an NRP-1-mediated targeting codelivery system sheds light on constructing an appealing candidate with translational potential by using clinically approved PDT and chemotherapy.

Identification of hypoxic macrophages in glioblastoma with therapeutic potential for vasculature normalization

Monocyte-derived tumor-associated macrophages (Mo-TAMs) intensively infiltrate diffuse gliomas with remarkable heterogeneity. Using single-cell transcriptomics, we chart a spatially resolved transcriptional landscape of Mo-TAMs across 51 patients with isocitrate dehydrogenase (IDH)-wild-type glioblastomas or IDH-mutant gliomas. We characterize a Mo-TAM subset that is localized to the peri-necrotic niche and skewed by hypoxic niche cues to acquire a hypoxia response signature. Hypoxia-TAM destabilizes endothelial adherens junctions by activating adrenomedullin paracrine signaling, thereby stimulating a hyperpermeable neovasculature that hampers drug delivery in glioblastoma xenografts. Accordingly, genetic ablation or pharmacological blockade of adrenomedullin produced by Hypoxia-TAM restores vascular integrity, improves intratumoral concentration of the anti-tumor agent dabrafenib, and achieves combinatorial therapeutic benefits. Increased proportion of Hypoxia-TAM or adrenomedullin expression is predictive of tumor vessel hyperpermeability and a worse prognosis of glioblastoma. Our findings highlight Mo-TAM diversity and spatial niche-steered Mo-TAM reprogramming in diffuse gliomas and indicate potential therapeutics targeting Hypoxia-TAM to normalize tumor vasculature.