Tumor Blood Vessels Research Articles

RNA Nanotechnology for Codelivering High-Payload Nucleoside Analogs to Cancer with a Synergetic Effect.

Nucleoside analogs are potent inhibitors for cancer treatment, but the main obstacles to their application in humans are their toxicity, nonspecificity, and lack of targeted delivery tools. Here, we report the use of RNA four-way junctions (4WJs) to deliver two nucleoside analogs, floxuridine (FUDR) and gemcitabine (GEM), with high payloads through routine and simple solid-state RNA synthesis and nanoparticle assembly. The design of RNA nanotechnology for the co-delivery of nucleoside analogs and the chemotherapeutic drug paclitaxel (PTX) resulted in synergistic effects and high efficacy in the treatment of Triple-Negative Breast Cancer (TNBC). The 4WJ-drug complexes were confirmed to have efficient tumor spontaneous targeting and no toxicity because the motility of RNA nanoparticles has been previously shown to enable these RNA-drug complexes to spontaneously accumulate in tumor blood vessels. The negative charge of RNA enables those RNA complexes that are not targeted to tumor vasculature to circulate in the blood and enter the urine through the kidney glomerulus, without accumulating in organs, therefore being nontoxic. Drug incorporation into RNA 4WJ can be precisely controlled with a defined loading amount, location, and ratio. The incorporation of nucleoside analogs into 4WJ only requires one step using nucleoside analogue phosphoramidites during solid-phase RNA synthesis, without the need for additional conjugation and purification processes.

Losartan rewires the tumor-immune microenvironment and suppresses IGF-1 to overcome resistance to chemo-immunotherapy in ovarian cancer.

Ovarian cancer (OvCa) is the most lethal of the gynecologic malignancies. Immune checkpoint inhibitors, which have revolutionized the treatment of multiple malignancies, have had limited efficacy in OvCa patients. This lack of effectiveness is partly due to the abnormal ovarian tumor microenvironment (TME), displaying a desmoplastic, highly fibrotic extracellular matrix. High extracellular matrix deposition leads to a buildup of compressive forces that cause tumor blood vessel collapse, reduced vessel perfusion, poor delivery of drugs, and compromised trafficking of cytotoxic T-cells to these tumors. Using two syngeneic OvCa models, we tested the effect of losartan, a widely prescribed anti-hypertensive drug, on reprogramming the TME and chemosensitizing the cancer cells. Losartan treatment (i) reprograms the TME leading to increased vascular perfusion, and thus enhances drug delivery and immune effector cell intratumoral infiltration and function; and (ii) rewires the OvCa cells by suppressing the IGF-1 signaling, resulting in enhanced chemosensitivity. As a result of the combined tumor and stromal effects, losartan treatment enhances the efficacy of chemo-immunotherapy in OvCa models. The safety and low cost ( < $1-2/day) of losartan warrant rapid translation of our findings to patients with OvCa.

HCC spatial transcriptomic profiling reveals significant and potentially targetable cancer-endothelial interactions.

HCC is a highly vascular tumor, and many effective drug regimens target the tumor blood vessels. Prior bulk HCC subtyping data used bulk transcriptomes, which contained a mixture of parenchymal and stromal contributions. We utilized computational deconvolution and cell-cell interaction analyses to cell type-specific (tumor-enriched and vessel-enriched) spatial transcriptomic data collected from 41 resected HCC tissue specimens. We report that the prior Hoshida bulk transcriptional subtyping schema is driven largely by an endothelial fraction, show an alternative tumor-specific schema has potential prognostic value, and use spatially paired ligand-receptor analyses to identify known and novel (LGALS9 tumor-HAVCR2 vessel) signaling relationships that drive HCC biology in a subtype-specific and potentially targetable manner. Our study leverages spatial gene expression profiling technologies to dissect HCC heterogeneity and identify heterogeneous signaling relationships between cancer cells and their endothelial cells. Future validation and expansion of these findings may validate novel cancer-endothelial cell interactions and related drug targets.

Exposed Phosphatidylserine as a Biomarker for Clear Identification of Breast Cancer Brain Metastases in Mouse Models.

Brain metastasis is the most common intracranial malignancy in adults. The prognosis is extremely poor, partly because most patients have more than one brain lesion, and the currently available therapies are nonspecific or inaccessible to those occult metastases due to an impermeable blood-tumor barrier (BTB). Phosphatidylserine (PS) is externalized on the surface of viable endothelial cells (ECs) in tumor blood vessels. In this study, we have applied a PS-targeting antibody to assess brain metastases in mouse models. Fluorescence microscopic imaging revealed that extensive PS exposure was found exclusively on vascular ECs of brain metastases. The highly sensitive and specific binding of the PS antibody enables individual metastases, even micrometastases containing an intact BTB, to be clearly delineated. Furthermore, the conjugation of the PS antibody with a fluorescence dye, IRDye 800CW, or a radioisotope, 125I, allowed the clear visualization of individual brain metastases by optical imaging and autoradiography, respectively. In conclusion, we demonstrated a novel strategy for targeting brain metastases based on our finding that abundant PS exposure occurs on blood vessels of brain metastases but not on normal brain, which may be useful for the development of imaging and targeted therapeutics for brain metastases.

Sialyl Lewis X decorated integrin α3 on small extracellular vesicles promotes metastasis of bladder cancer via enhancing vascular permeability.

The permeability of blood vessels plays a crucial role in the spread of cancer cells, facilitating their metastasis at distant sites. Small extracellular vesicles (sEVs) are known to contribute to the metastasis of various cancers by crossing the blood vessel wall. However, the role of abnormal glycoconjugates on sEVs in tumor blood vessels remains unclear. Our study found elevated levels of fucosyltransferase VII (FUT7) and its product sialyl Lewis X (sLeX) in muscle-invasive bladder cancer (BLCA), with high levels of sLeX promoting the growth and invasion of BLCA cells. Further investigation revealed that sLeX was enriched in sEVs derived from BLCA. sLeX-decorated sEVs increased blood vessel permeability by disrupting the tight junctions of human umbilical vein endothelial cells (HUVECs). Using the glycoproteomics approach, we identified integrin α3 (ITGA3) as a sLeX-bearing glycoprotein in BLCA cells and their sEVs. Mechanically, sLeX modification stabilized ITGA3 by preventing its degradation in lysosomes. sEVs carrying sLeX-modified ITGA3 can be effectively internalized by HUVECs, leading to a decrease in the expression of tight junction protein. Conversely, silencing ITGA3 in sLeX-decorated sEVs restored tight junction proteins and reduced blood vessel permeability by inhibiting the MAPK pathway. Moreover, sLeX-modification of ITGA3 at Asn 265 in HUVECs promoted occludin dephosphorylation at Ser/Thr residues, followed by inducing its importin α1-mediated nuclear translocation, which resulted in the disruption of tight junctions. Our findings suggest a potential strategy for disrupting the formation of a metastatic microenvironment and preventing the spread of malignant bladder cancer.

The impact of Kirsten rat sarcoma (KRAS) status on local tumor progression after surgical ablation of colorectal liver metastases

BackgroundKirsten rat sarcoma mutation was reported to adversely affect local tumor control after percutaneous ablation of colorectal liver metastasis. Nevertheless, the effect of Kirsten rat sarcoma mutation on surgical ablation has not been investigated in the literature. The aim of this study is to analyze the impact of Kirsten rat sarcoma mutation on local recurrence after surgical ablation of colorectal liver metastasis. MethodsThis was an institutional review board–approved study of patients who underwent surgical ablation of colorectal liver metastasis between 2005 and 2023 at a single center and underwent Kirsten rat sarcoma testing with ≥1 year follow-up. Local recurrence was analyzed using univariate Kaplan–Meier and multivariate Cox hazard models. ResultsA total of 163 patients with 424 lesions fulfilled inclusion criteria. Fifty (30.7%) patients received radiofrequency ablation and 113 (69.3%) patients received microwave ablation. Fifty-seven patients (32.2%) with 177 lesions were found to have a Kirsten rat sarcoma mutation. Patients with Kirsten rat sarcoma mutation had a larger number of tumors, percentage of posteriorly located tumors, and tumor burden score compared with those with wild-type Kirsten rat sarcoma. Nevertheless, there was no difference between the groups regarding local recurrence per lesion (15% vs 17%, respectively, P = not significant). Independent predictors of local recurrence included tumor size, ablation margin, and blood vessel proximity for radiofrequency ablation compared with tumor size and ablation margin for microwave ablation. ConclusionThere was no effect of Kirsten rat sarcoma mutations on local recurrence after surgical radiofrequency ablation or microwave ablation of colorectal liver metastasis in this study. Tumor size and ablation margin remained as independent predictors.

Relationship between the white blood cell count and some lipid profile parameters in cancer patients with myocardial infarction

Hokkaido University (Tsumita T, 2022) researchers found that endothelial cells accumulate low-density lipoproteins (LDL) in tumor blood vessels. At the same time, the endothelium carries out neutrophil chemotaxis, which perform an immunosuppressive function contributing to cancer progression.Aim. To search for the relationship between the white blood cell (WBC) count and some lipid profile parameters in cancer patients with myocardial infarction (MI).Material and methods. We examined 319 patients who were treated at Dzhanelidze Research Institute of Emergency Medicine in 2018-2023, which were divided into three groups: MI in combination with an active cancer — 132 patients (Group I), MI+cancer in history — 58 patients (Group II), MI without cancer — 129 patients (Group III). Following laboratory data used in routine practice were assessed: WBC count, relative neutrophil count, total cholesterol, low-density lipoproteins.Results. Cancer patients with MI are characterized by higher WBC and neutrophil count than in other samples However, the total cholesterol level was significantly lower in this sample, and the LDL level was not significantly different. Patients with MI and previous cancer occupied an intermediate position between groups I and III in terms of studied parameters.Conclusion. In general, data on the role of cholesterol levels in cancer patients are contradictory. In particular, some studies have shown that elevated cholesterol levels are a potential risk factor for cancer. In our study, as in a number of others, no significant associations were identified between elevated cholesterol levels and the presence of cancer. Our study is a step towards understanding the connection between the cholesterol concentration and the immune response in cancer patients with MI.

Lymphatic and blood vessels in parathyroid tumors: Immunohistochemical study with LYVE-1 and von Willebrand factor.

Parathyroid tumors exhibit distinct histopathological features that differentiate benign from malignant lesions. This study aimed to study characteristic distribution of lymphatic and blood vessels in normal parathyroid gland and parathyroid tumors to distinguish cancer from benign tumors. Immunohistochemical staining for lymphatic and blood vessels and parathyroid hormone was performed with parathyroid proliferating lesions including adenoma, multiglandular multiple adenomas, atypical tumor, and carcinoma. Lymphatic vessels were immunostained with lymphatic vessel endothelial receptor 1 (LYVE-1) and blood vessels were immunostained with von Willebrand factor (vWf). Normal parathyroid gland contained several round blood vessels with less linear lymphatic vessels. The less parathormone-immunostained adenomas weighing less than 2 g revealed larger blood vessels with perivascular small linear lymphatic vessels, and the larger adenomas contained proportionally larger blood vessels. Smaller multiglandular multiple adenomas were like smaller adenomas with less parathormone staining and contained larger, round blood vessels with perivascular small linear lymphatic vessels. Larger multiglandular multiple adenomas weighing more than 4 g and one atypical tumor contained nodular pattern consisted of alternating strongly parathormone-positive lobes and negative lobes with numerous, dilated blood vessels and perivascular linear lymphatic vessels. Both primary and metastatic carcinomas were strongly and diffusely positive for parathyroid hormone with numerous lymphatic and blood vessels at the invading margin. Thus, normal parathyroid has rich blood vessels which provide accessibility of minced tissues seeding for auto-transplantation. Immunostaining patterns of parathyroid hormone, lymphatic and blood vessels help to distinguish carcinoma from benign parathyroid proliferating lesions. The negative immunohistochemical staining for parafibromin will detect carriers of hyperparathyroidism-jaw tumor (HPT-JT) syndrome and would help in diagnosing parathyroid cancer in both HPT-JT carriers and sporadic patients.

Modified C-type natriuretic peptide normalizes tumor vasculature, reinvigorates antitumor immunity, and improves solid tumor therapies.

Deficit of oxygen and nutrients in the tumor microenvironment (TME) triggers abnormal angiogenesis that produces dysfunctional and leaky blood vessels, which fail to adequately perfuse tumor tissues. Resulting hypoxia, exacerbation of metabolic disturbances, and generation of an immunosuppressive TME undermine the efficacy of anticancer therapies. Use of carefully scheduled angiogenesis inhibitors has been suggested to overcome these problems and normalize the TME. Here, we propose an alternative agonist-based normalization approach using a derivative of the C-type natriuretic peptide (dCNP). Multiple gene expression signatures in tumor tissues were affected in mice treated with dCNP. In several mouse orthotopic and subcutaneous solid tumor models including colon and pancreatic adenocarcinomas, this well-tolerated agent stimulated formation of highly functional tumor blood vessels to reduce hypoxia. Administration of dCNP also inhibited stromagenesis and remodeling of the extracellular matrix and decreased tumor interstitial fluid pressure. In addition, treatment with dCNP reinvigorated the antitumor immune responses. Administration of dCNP decelerated growth of primary mouse tumors and suppressed their metastases. Moreover, inclusion of dCNP into the chemo-, radio-, or immune-therapeutic regimens increased their efficacy against solid tumors in immunocompetent mice. These results demonstrate the proof of principle for using vasculature normalizing agonists to improve therapies against solid tumors and characterize dCNP as the first in class among such agents.

Successful pancreatectomy after conversion-intended chemotherapy using gemcitabine and nab-paclitaxel for unresectable adenosquamous carcinoma of the pancreas: a case report

BackgroundAdenosquamous carcinoma of the pancreas (ASCP) accounts for only 1–4% of all pancreatic exocrine cancers and has a particularly poor prognosis. The efficacy of chemotherapy for ASCP remains unknown because of the small number of cases, and few studies have evaluated conversion-intended chemotherapy.Case presentationA 76-year-old woman was referred to our hospital because of epigastric pain and nausea. A preoperative contrast-enhanced multidetector row computed tomography (MDCT) scan revealed a 17 × 17 mm low-density tumor with an ill-defined margin at the arterial phase in the pancreatic head. The tumor involved the common hepatic artery, left hepatic artery bifurcated from the common hepatic artery, and gastroduodenal artery, and was in contact with the portal vein. Fluorodeoxyglucose-positron emission tomography (FDG-PET) showed an uptake in the pancreatic head but no evidence of distant metastasis. The tumor was diagnosed as an adenocarcinoma of the pancreatic head and staged unresectable because the common and left hepatic arteries were involved. Hence, the patient underwent seven courses of conversion-intended chemotherapy using gemcitabine and nab-paclitaxel for pancreatic ductal adenocarcinoma over 7 months. After chemotherapy, the tumor shrank to 10 × 10 mm on contrast-enhanced MDCT. Consequently, the boundary between the tumor and major vessels of the common and left hepatic arteries and the portal vein became clear, and the involvement of the arteries with the tumor was evaluated to be released. The contact of the tumor to the portal vein also reduced to less than half the circumference of the portal vein. FDG-PET showed decreased accumulation in the tumor. Hence, the tumor was judged resectable, and pancreaticoduodenectomy was performed. The tumor and major blood vessels were easily dissected and R0 resection was achieved. The patient experienced no major complications and was discharged on postoperative day 28. The tumor was revealed as ASCP via pathological examination. The patient is alive and recurrence-free seven months after surgery. This is the first report of successful R0 resection for an initially unresectable ASCP following conversion-intended chemotherapy using gemcitabine and nab-paclitaxel regimen. ConclusionsConversion-intended chemotherapy using gemcitabine and nab-paclitaxel regimen may be effective for ASCP.

Theoretical study of discriminative electroporation effect between tumor and normal blood vessels by high-frequency bipolar and traditional monopolar pulses

Theoretical study of discriminative electroporation effect between tumor and normal blood vessels by high-frequency bipolar and traditional monopolar pulses

30 Synergistic systematic analysis with fully human tissue models andin silico modeling of “copycats” reveals mechanisms of T cell suppression in clear cell renal cell carcinoma

Abstract Background Immune checkpoint-inhibitors have become a standard treatment for clear cell renal cell carcinoma (ccRCC). However, responses to checkpoint-inhibition are heterogeneous and many patients are resistant or eventually develop resistance. A better understanding of functional mechanisms governing immune responses in ccRCC is needed to identify biomarkers for therapeutic responses and to unravel novel therapeutic targets to overcome primary or acquired resistance to therapies. Methods We developed a fully human explant model derived from freshly resected ccRCC tissue (Fig. 1A). Our tissue explant model preserves all components of the tumor microenvironment including not only tumor cells, but also the immune cell compartment as well as tumor-stroma and -vasculature in culture (Fig. 1B). Following treatment with combined checkpoint-inhibition (Nivolumab plus Ipilimumab) or an anti-CCR5 inhibitor (Maraviroc), the tissue explants were analyzed by immunohistochemistry staining and multiplex cytokine profiling of 50 cytokines. Spatial and functional insights were incorporated in an agent-based in silico model (PhysiCell, Ghaffarizadeh et al., PLoS Comput. Biol., 2018) for unlimited exploration of functional cellular dynamics in the tumor microenvironment (Fig. 1D). Results Immunohistochemical analyses and cytokine profiling of ccRCC-tissue explants showed heterogeneous immune responses among different patients and indicated an impaired cytotoxic T cell response following checkpoint-inhibition (Fig. 1C). Spatial analyses of immune cell populations revealed clusters of CD8+ T cells and CD163+ macrophages localized closely to CD31+ endothelial cells. Further characterization of the tumor microenvironment revealed high CCR5-expression in the tumor, particularly on the tumor blood vessels (Fig. 1B). Treatment of the tissue explants with the anti-CCR5 inhibitor Maraviroc led to an increase of CD8+ T cells and cytotoxic cytokines (Granzyme B, IFNgamma, TNFalpha, IFNalpha2) in the tumor in comparison to checkpoint-inhibition (Fig. 1C). Spatial and functional information from cultured ccRCC-tissue explants were integrated into an agent-based in silico model of the ccRCC tumor microenvironment, which includes tumor cells, T cells, macrophages and endothelial cells (Fig. 1D). In silico simulation of different immune cell modulating treatment conditions showed an increase of T cells and cytotoxic cytokines upon blockade of the interaction between T cells with endothelial cells or macrophages (Fig. 1E). Conclusions Our combined ex vivo and in silico analyses provide evidence for immunosuppression in the ccRCC tumor microenvironment mediated by macrophages and endothelial cells. CCR5 was shown to be a potential target to overcome immune resistance to checkpoint-inhibition in ccRCC. Further characterization of immune cell compositions and functional mechanisms in the perivascular area is imperative to enhance therapeutic responses to immunotherapies for ccRCC.

Normalization of Snai1-mediated vessel dysfunction increases drug response in cancer

Blood vessels in tumors are often dysfunctional. This impairs the delivery of therapeutic agents to and distribution among the cancer cells. Subsequently, treatment efficacy is reduced, and dose escalation can increase adverse effects on non-malignant tissues. The dysfunctional vessel phenotypes are attributed to aberrant pro-angiogenic signaling, and anti-angiogenic agents can ameliorate traits of vessel dysfunctionality. However, they simultaneously reduce vessel density and thereby impede drug delivery and distribution. Exploring possibilities to improve vessel functionality without compromising vessel density in the tumor microenvironment, we evaluated transcription factors (TFs) involved in epithelial-mesenchymal transition (EMT) as potential targets. Based on similarities between EMT and angiogenic activation of endothelial cells, we hypothesized that these TFs, Snai1 in particular, might serve as key regulators of vessel dysfunctionality. In vitro, experiments demonstrated that Snai1 (similarly Slug and Twist1) regulates endothelial permeability, permissiveness for tumor cell transmigration, and tip/stalk cell formation. Endothelial-specific, heterozygous knock-down of Snai1 in mice improved vascular quality in implanted tumors. This resulted in better oxygenation and reduced metastasis. Notably, the tumors in Snai1KD mice responded significantly better to chemotherapeutics as drugs were transported into the tumors at strongly increased rates and more homogeneously distributed. Thus, we demonstrate that restoring vessel homeostasis without affecting vessel density is feasible in malignant tumors. Combining such vessel re-engineering with anti-cancer drugs allows for strategic treatment approaches that reduce treatment toxicity on non-malignant tissues.

Targeting a STING agonist to perivascular macrophages in prostate tumors delays resistance to androgen deprivation therapy

BackgroundAndrogen deprivation therapy (ADT) is a front-line treatment for prostate cancer. In some men, their tumors can become refractory leading to the development of castration-resistant prostate cancer (CRPC). This causes...

Metformin synergizes with PD-1 blockade to promote normalization of tumor vessels via CD8T cells and IFNγ

Tumor blood vessels are highly leaky in structure and have poor blood perfusion, which hampers infiltration and function of CD8T cells within tumor. Normalizing tumor vessels is thus thought to be important in promoting the flux of immune T cells and enhancing ant-tumor immunity. However, how tumor vasculature is normalized is poorly understood. Metformin (Met) combined with ant-PD-1 therapy is known to stimulate proliferation of and to produce large amounts of IFNγ from tumor-infiltrating CD8T lymphocytes (CD8TILs). We found that the combination therapy promotes the pericyte coverage of tumor vascular endothelial cells (ECs) to improve blood perfusion and that it suppresses the hyperpermeability through the increase of VE-cadherin. Peripheral node addressin(PNAd) and vascular cell adhesion molecule (VCAM)-1, both implicated to promote tumor infiltration of CD8T cells, were also increased. Importantly, tumor vessel normalization, characterized as the reduced 70-kDa dextran leakage and the enhancement of VE-cadherin and VCAM-1, were canceled by anti-CD8 Ab or anti-IFNγ Ab injection to mice. The increased CD8TILs were also abrogated by anti-IFNγ Ab injection. In vascular ECs, flow cytometry analysis revealed that pSTAT1 expression was found to be associated with VE-cadherin expression. Moreover, in vitro treatment with Met and IFNγ enhanced VE-cadherin and VCAM-1 on human umbilical vein endothelial cells (HUVECs). The Kaplan-Meier method revealed a correlation of VE-cadherin or VCAM-1 levels with overall survival in patients treated with immune checkpoint inhibitors. These data indicate that IFNγ-mediated cross talk of CD8TILs with tumor vessels is important for creating a better tumor microenvironment and maintaining sustained antitumor immunity.

Therapeutic Anti-Tumor Efficacy of DC-Based Vaccines Targeting TME-Associated Antigens Is Improved When Combined with a Chemokine-Modulating Regimen and/or Anti-PD-L1.

We previously reported that dendritic cell (DC)-based vaccines targeting antigens expressed by tumor-associated vascular endothelial cells (VECs) and pericytes effectively control tumor growth in translational mouse tumor models. In the current report, we examined whether the therapeutic benefits of such tumor blood vessel antigen (TBVA)-targeted vaccines could be improved by the cotargeting of tumor antigens in the s.c. B16 melanoma model. We also evaluated whether combination vaccines incorporating anti-PD-L1 checkpoint blockade and/or a chemokine-modulating (CKM; IFNα + TLR3-L [rintatolimod] + Celecoxib) regimen would improve T cell infiltration/functionality in tumors yielding enhanced treatment benefits. We report that DC-peptide or DC-tumor lysate vaccines coordinately targeting melanoma antigens and TBVAs were effective in slowing B16 growth in vivo and extending survival, with superior outcomes observed for DC-peptide-based vaccines. Peptide-based vaccines that selectively target either melanoma antigens or TBVAs elicited a CD8+ T cell repertoire recognizing both tumor cells and tumor-associated VECs and pericytes in vitro, consistent with a treatment-induced epitope spreading mechanism. Notably, combination vaccines including anti-PD-L1 + CKM yielded superior therapeutic effects on tumor growth and animal survival, in association with the potentiation of polyfunctional CD8+ T cell reactivity against both tumor cells and tumor-associated vascular cells and a pro-inflammatory TME.

Accumulation of liposomes in metastatic tumor sites is not necessary for anti-cancer drug efficacy

BackgroundThe tumor microenvironment is profoundly heterogeneous particularly when comparing sites of metastases. Establishing the extent of this heterogeneity may provide guidance on how best to design lipid-based drug delivery systems to treat metastatic disease. Building on our previous research, the current study employs a murine model of metastatic cancer to explore the distribution of ~ 100 nm liposomes. MethodsFemale NCr nude mice were inoculated with a fluorescently labeled, Her2/neu-positive, trastuzumab-resistant breast cancer cell line, JIMT-1mkate, either in the mammary fat pad to create an orthotopic tumor (OT), or via intracardiac injection (IC) to establish tumors throughout the body. Animals were dosed with fluorescent and radio-labeled liposomes. In vivo and ex vivo fluorescent imaging was used to track liposome distribution over a period of 48 h. Liposome distribution in orthotopic tumors was compared to sites of tumor growth that arose following IC injection. ResultsA significant amount of inter-vessel heterogeneity for DiR distribution was observed, with most tumor blood vessels showing little to no presence of the DiR-labelled liposomes. Further, there was limited extravascular distribution of DiR liposomes in the perivascular regions around DiR-positive vessels. While all OT tumors contained at least some DiR-positive vessels, many metastases had very little or none. Despite the apparent limited distribution of liposomes within metastases, two liposomal drug formulations, Irinophore C and Doxil, showed similar efficacy for both the OT and IC JIMT-1mkate models. ConclusionThese findings suggest that liposomal formulations achieve therapeutic benefits through mechanisms that extend beyond the enhanced permeability and retention effect.

Redox-responsive hyaluronic acid-celastrol prodrug micelles with glycyrrhetinic acid co-delivery for tumor combination therapy

Combining cytotoxic drugs with tumor microenvironment (TME) modulator agents is an effective strategy to enhance anti-tumor effects. In this study, two natural anti-tumor active ingredients celastrol (CEL) and glycyrrhetinic acid (GA) were combined for tumor treatment. In order to ensure the precise co-delivery and controllable synchronous release of combined drugs to tumors, it is necessary to construct a suitable nano-drug delivery platform. Based on this, we coupled hyaluronic acid (HA) with CEL by amide reaction to obtain an amphiphilic polymer prodrug HA-SS-CEL, and GA was spontaneously loaded into polymer micelles by self-assembly to obtain G/HSSC-M. G/HSSC-M has ideal size distribution, redox-responsive synchronous drug release, enhanced tumor cell internalization and in vivo tumor targeting. Compared with free drugs, the construction of multifunctional polymer micelles makes G/HSSC-M show better anticancer effect at the same concentration, and can significantly inhibit the proliferation and migration of HepG2 and 4T1 cells. In the in vivo experiments, G/HSSC-M inhibited tumor as high as 75.12% in H22 tumor-bearing mice. The mechanism included regulation of M1/M2 macrophage polarization, inhibition of Janus kinase 1/signal transducer and activator of transcription 3 (JAK1/STAT3) signaling pathway, and remodeling of tumor blood vessels. Therefore, the development of prodrug micelles co-loaded with CEL and GA provides a promising drug co-delivery strategy for combined cancer therapy.

Epstein-Barr virus causes vascular abnormalities in epithelial malignancies through upregulating ANXA3-HIF-1α-VEGF pathway.

Angiogenesis is one of the characteristics of malignant tumors, and persistent generation of abnormal tumor blood vessels is an important factor contributing to tumor treatment resistance. Epstein-Barr virus (EBV) is a highly prevalent DNA oncogenic virus that is associated with the development of various epithelial malignancies. However, the relationship between EBV infection and tumor vascular abnormalities as well as its underlying mechanisms is still unclear. In this study, we found that compared to EBV-uninfected tumors, EBV-infected tumors were more angiogenic, but the neovascularization was mostly immature vessels without pericyte attachment in both clinical patient tumor samples and mouse xenograft models; These immature vessels exhibited aberrant functionality, characterized by poor blood perfusion and increased vascular permeability. The vascular abnormalities caused by EBV infection exacerbated tumor hypoxia and was responsible for accelerated tumor growth. Mechanistically, EBV infection upregulated ANXA3-HIF-1α-VEGF pathway. Silencing the ANXA3 gene or neutralizing ANXA3 with an antibody can diminish vascular abnormalities, thereby increasing immune cell infiltration and alleviating treatment resistance. Finally, a new therapy combining ANXA3 blockade and NK cell + PD1 antibody significantly inhibited the growth of EBV-infected xenografts in mice. In conclusion, our study identified a previously unrecognized role for EBV infection in tumor vascular abnormalities and revealed its underlying mechanism that upregulated the ANXA3-HIF-1α-VEGF pathway. ANXA3 is a potential therapeutic target for EBV-infected tumors and ANXA3 blockade to improve vascular conditions, in combination with NK cell + PD1 antibody therapy, holds promise as an effective treatment strategy for EBV-associated epithelial malignancies.

Plasma GPI and PGD are associated with vascular normalization and may serve as novel prognostic biomarkers for lung adenocarcinoma: Multi-omics and multi-dimensional analysis

The aim of this study was to explore potential novel plasma protein biomarkers for lung adenocarcinoma (LUAD). A plasma proteomics analysis was carried out and candidate protein biomarkers were validated in 102 LUAD cases and 102 matched healthy controls. The same LUAD tumor tissues were detected to explore the correlation between the expression of candidate proteins in tissues and plasma and vascular normalization. A LUAD active metastasis mice model was constructed to explore the role of candidate proteins for lung metastasis. GPI and PGD were verified to be upregulated in plasma from LUAD patients, and the expression of GPI in tumor tissue was positively correlated with the expression of GPI in plasma and negatively correlated with the normalization of tumor blood vessels. Meanwhile, a negative correlation between the expression of GPI and PGD in plasma and tumor vascular normalization was discovered. In the LUAD active metastasis model, the lowest levels of vascular normalization and the highest expression of GPI and PGD were found in mice with lung metastases. This study found that GPI and PGD may be potential plasma biomarkers for LUAD, and monitoring those may infer the risk of metastasis and malignancy of the tumor. SignificantWe identified GPI and PGD as potential novel diagnostic and prognostic biomarkers for LUAD. PGD and GPI can be used as diagnostic biomarkers in combination with other available strategies to assist in the screening and diagnosis of LUAD, and as prognostic biomarkers aid in predict the risk of tumor metastasis and malignancy in patients with LUAD.