Vascular normalization as an emerging strategy to enhance cancer immunotherapy

Low- dose Apatinib promotes vascular normalization and hypoxia reduction and sensitizes radiotherapy in lung cancer

BACKGROUND AND PURPOSE

Abnormal vascular network of tumor can create a hypoxic microenvironment, and reduce radiotherapy sensitivity. Normalization of tumor vasculature can be a new therapeutic strategy for sensitizing radiotherapy. This study aimed to explore the effect of apatinib on vascular normalization, as well as the syngeneic effect with radiotherapy on lung cancer.

MATERIALS AND METHODS

Lewis lung carcinoma (LLC) xenograft-bearing female C57BL/6 mice were treated with different doses of apatinib (30, 60, and 120 mg/kg per day) and/or radiation therapy (8 Gy/1F) and then sacrificed to harvest tumor tissue for immunohistochemical test. Further ¹⁸ F-FMISO micro- PET in vivo explored the degree of hypoxia.

RESULTS

Immunohistochemistry of CD31 and alpha-smooth muscle actin (α-SMA) proved that low-dose apatinib can normalize vasculature in tumor, especially on Day 10. Tissue staining of hypoxyprobe-1 and ¹⁸ F-FMISO micro- PET in vivo showed that 60 mg/kg/day of apatinib significantly alleviates hypoxia. Moreover, this study further proved that low-dose apatinib (60 mg/kg/day) can enhance the radio-response of LLC xenograft mice.

CONCLUSION

Our data suggested that low- dose apatinib can successfully induce a vascular normalization window and function as a radio- sensitizer in the lung cancer xenografts model.

The combined effect and mechanism of antiangiogenic drugs and PD-L1 inhibitor on cell apoptosis in triple negative breast cancer

Background

Breast cancer is the most common cancer worldwide, and triple-negative breast cancer (TNBC) has the worst prognosis. Standard systemic treatment includes chemotherapy and immunotherapy. Poly ADP-ribose polymerase (PARP) inhibitors are considered in breast cancer (BRCA) susceptibility genes mutated tumors. The role of antiangiogenic drugs is controversial. Immunotherapy with immune checkpoint inhibitor is now a standard of care for TNBC in the US, but its use in combination with anlotinib, an inhibitor of angiogenesis, on TNBC cells was never investigated.

Methods

We tested the effects of anlotinib and programmed cell death-ligand 1 (PD-L1) inhibitor on the proliferation, apoptosis, migration, and invasion of MDA-MB-468 and BT-549 TNBC cells through 3-(4,5-dimethylthiazol-2-Yl)-2,5-diphenyltetrazolium bromide (MTT) assays, cell apoptosis assay, wound healing and transwell matrix assays, and verified whether the combination of the two drugs had synergistic effect. Western blotting was used to detect the effect of anlotinib and PD-L1 inhibitor on the protein expression levels of PI3K, p-PI3K, AKT, p-AKT, Bcl-xl in MDA-MB-468 and BT-549 cells. The effects of anlotinib, PD-L1 inhibitor and the combination of the two drugs on the transplanted tumor of TNBC mice were tested by animal experiments.

Results

Anlotinib and PD-L1 inhibitor inhibited the proliferation and promote cell apoptosis of MDA-MB-468 and BT-549 cells, and the combination demonstrated the synergetic effect. Anlotinib and PD-L1 inhibitor inhibited cell migration and invasion, and the effect was strongest in the combination group. Both anlotinib and PD-L1 inhibitor reduced the expression of p-PI3K, p-AKT and Bcl-xl proteins in cells and the effects were the strongest in the combination group. Both anlotinib and PD-L1 inhibitor inhibited the growth of transplanted tumors in mice, and the combined group demonstrated the strongest growth suppression.

Conclusions

Anlotinib and PD-L1 inhibitor can inhibit cell proliferation, migration, and invasion of TNBC and promote cell apoptosis, and the two drugs show combined anti-tumor effects in vivo and in vitro. The combination of anlotinib and PD-L1 inhibitor may promote apoptosis of TNBC cells through PI3K/AKT/Bcl-xl signaling pathways, which might offer potential clinical treatment roles for these.

Enhancing Photothermal Therapy Efficacy by In Situ Self-Assembly in Glioma

The residence time of some small molecular imaging and therapeutic agents in tumor tissue is short and the molecules can be easily dispersed, which decreases treatment efficacy. Therefore, methods that enhance oncotherapy performance are of significant importance. Here, we report an in situ self-assembly strategy aimed at enhancing the photothermal therapy of glioblastomas. The probe, ICG-PEP-c(RGD)fk, consisted of a glutathione-reactive self-assembling polypeptide as the skeleton, indocyanine green (ICG) as a theranostic agent, and cyclic Arg-Gly-Asp [c(RGD)fk] peptides as the targeting group. ICG-PEP-c(RGD)fk was synthesized and found to be assembled in the glutathione environment at 9.446 μM in vitro. Human glioblastoma cell line U87MG-luc with high integrin αvβ3 expression was applied to invivo experiments. ICG-PEP-c(RGD)fk provided clearer tumor imaging and had a tumor retention time of 6.12 times longer than that of ICG-c(RGD)fk. In therapeutic experiments, ICG-PEP-c(RGD)fk significantly suppressed glioblastoma growth and the tumor volume was 2.61 times smaller than in the ICG-c(RGD)fk group at the end of the observation period. Moreover, the median survival time of ICG-PEP-c(RGD)fk group was significantly improved by 2.78 times compared with that of the control group. In conclusion, glutathione-reactive self-assembling peptides are capable of increasing the tumor retention time and improving the photothermal therapeutic effect. The in situ self-assembly strategy is a potential and feasible method to enhance oncotherapy.

Novel considerations on EGFR-based therapy as a contributor to cancer cell death in NSCLC

Epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs) represented by gefitinib and erlotinib are widely used in treating non-small cell lung cancer (NSCLC). However, acquired resistance to EGFR-TKI treatment remains a clinical challenge. In recent years, emerging research investigated in EGFR-TKI-based combination therapy regimens, and remarkable achievements have been reported. This article focuses on EGFR-TKI-based regimens, reviews the standard and novel application of EGFR targets, and summarizes the mechanisms of EGFR-TKI combinations including chemotherapy, anti-vascular endothelial growth factor monoclonal antibodies, and immunotherapy in the treatment of NSCLC. Additionally, we summarize clinical trials of EGFR-TKI-based combination therapy expanding indications to EGFR mutation-negative lung malignancies. Moreover, novel strategies are under research to explore new drugs with good biocompatibility. Nanoparticles encapsulating non-coding RNA and chemotherapy of new dosage forms drawn great attention and showed promising prospects in effective delivery and stable release. Overall, as the development of resistance to EGFR-TKIs treatment is inevitable in most of the cases, further research is needed to clarify the underlying mechanism of the resistance, and to evaluate and establish EGFR-TKI combination therapies to diversify the treatment landscape for NSCLC.

Nivolumab-induced capillary leak syndrome associated with chylothorax in a melanoma patient: A case report and review of the literature

Introduction

Adverse events (AEs) of immune checkpoint inhibitors (ICIs) are frequent and mainly due to an overactivity of the immune system leading to excessive inflammatory responses (immune-related AE) that can affect any organ of the body. Beside the most frequent AEs, there are rare AEs whose diagnosis and treatment can be challenging. We report here a singular case of capillary leak syndrome (CLS) associated with chylothorax occurring in a patient who has been treated with adjuvant nivolumab (anti-PD1) for resected AJCC stage IIB primary melanoma.

Case presentation

A 43-year-old woman was diagnosed with a nodular stage IIB melanoma of her left thigh, according to the AJCC 8th edition (T3bN0M0). The woman was treated with adjuvant nivolumab. She stopped the treatment after 4 infusions due to thrombopenia. Three months later, she developed facial and leg edema and ascites due to capillary leak syndrome. The CLS was associated with chylothorax and elevated vascular endothelial growth factor. The patient was initially treated with several pleural puncturing and steroids. CLS and chylothorax progressively decreased with intravenous immunoglobulins and fat-free diet without recurrence of melanoma at one-year follow-up.

Conclusion

CLS is a rare and potentially life-threatening AE of ICIs such as anti-PD1. This AE may be associated with chylothorax probably related to lymphatic permeability induced by anti-PD1.

Data of programmed death-ligand 1 expression and VEGF: Nivolumab, bevacizumab and paclitaxel For HER2-negative metastatic breast cancer

The purpose was to explore potential biomarkers of the efficacy and toxicity of triple therapy of nivolumab, bevacizumab and paclitaxel in patients with HER2-negative metastatic breast cancer (MBC). Tumor tissues before treatment and blood samples at pretreatment, during and after treatment were collected. The serum samples were used to measure the concentrations of cytokines. Progression-free survival (PFS), overall survival (OS), and response were analyzed in association with the biomarker data using the Kaplan–Meier method and log-rank tests. Fifty patients were included in the biomarker analysis. Programmed death-ligand 1 (PD-L1) expression on tumor cells and immune cells were evaluated in tumor tissue samples using a Dako 28-8 immunohistochemistry assay and using a VENTANA SP142 immunohistochemistry assay. PD-L1 positive rates using anti-PD-L1 antibodies 28-8 (Combined positive score [CPS] ≥1) and SP142 (Immune cells [IC] ≥1) were 15% and 17%, respectively. The PFS and OS were not significantly different in the subgroups by PD-L1 expression. The median pretreatment vascular endothelial growth factor (VEGF)-A concentration was 116.1 pg/ml (range 0–740.23 pg/ml) on day 1 and decreased to <37 pg/ml on day 8 of cycle 1 in all patients. Subtypes (hormone receptor-positive HER2-negative or triple negative breast cancer), stage (recurrent or de novo stage IV) and liver metastasis (yes or no) were not significantly different between patients in VEGF-A high and VEGF-A low groups. PFS in the VEGF-A high group was similar to that in the VEGF-A low group.

Efficacy and safety comparison of PD-1 inhibitors vs. PD-L1 inhibitors in extensive-stage small-cell lung cancer: a retrospective comparative cohort study

Background

Evidence from clinical research and meta-analyses have suggested that programmed cell death 1 (PD-1) inhibitors and programmed cell death ligand 1 (PD-L1) inhibitors plus chemotherapy could achieve a significant survival benefit for extensive-stage small-cell lung cancer (ES-SCLC) patients. However clinical researches concerned about the comparation between the PD-1 and PD-L1 inhibitors were relatively lacking.

Methods

We collected the data of ES-SCLC patients treated with PD-1 inhibitors or PD-L1 inhibitors. The primary endpoints were overall survival (OS) and progression-free survival (PFS). Secondary endpoint included adverse events (AEs).

Results

The data of 221 ES-SCLC patients treated with PD-1 (n=146) or PD-L1 inhibitors (n=75) between February 2017 and June 2020 were retrospectively collected. The median OS (mOS) and median PFS (mPFS) were 19.07 and 8.27 months, respectively, in patients treated with PD-1 inhibitors. In the PD-L1 group, mOS has not been reached, and mPFS was 7.95 months. No significant differences were observed between the 2 groups in OS [hazard ratio (HR), 1.472; 95% confidence interval (CI), 0.847-2.220; P=0.198] and PFS (HR, 0.816; 95% CI, 0.577-1.155; P=0.251). The rates of patients showed AEs of any grade treated with PD-1 or PD-L1 were 67.12% and 64.00%, with no significant difference (P=0.642, χ²=0.216), ≥3 grade AEs occurred in 42 (28.76%) and 16 (21.33%) patients treated with PD-1 and PD-L1 inhibitors separately, also no significant difference (P=0.234, χ²=1.415) was observed. According to subgroup analysis, camrelizumab revealed a longer mPFS (15.17 months) compared with other immune-checkpoint inhibitors (ICIs). PD-1 and PD-L1 inhibitors revealed comparable efficacy in ES-SCLC patients with brain metastases, with no significant differences in OS (HR, 1.505; 95% CI, 0.684-3.311; P=0.309) and PFS (HR, 0.649; 95% CI, 0.356-1.182; P=0.157).

Conclusions

PD-1 and PD-L1 inhibitors might achieved comparable survival benefit and safety in ES-SCLC patients. A longer PFS was observed in patients treated with PD-1 inhibitors in the first-line treatment, and the PD-1 inhibitor camrelizumab might have achieved a better PFS compared with other ICIs.

Caerin 1.1/1.9 Enhances Antitumour Immunity by Activating the IFN-α Response Signalling Pathway of Tumour Macrophages

Macrophages are one of the essential components of the tumour microenvironment (TME) of many cancers and show complex heterogeneity and functions. More recent research has been focusing on the characterisation of tumour-associated macrophages (TAMs). Previously, our study demonstrated that caerin 1.1/1.9 peptides significantly improve the therapeutic efficacy of combined specific immunotherapy and immune checkpoint blockade in a murine transplantable tumour model (TC-1). In this study, the mice inoculated with TC-1 tumour were immunised differently. The TAMs were isolated using flow cytometry and characterised by cytokine ELISA. The survival rates of mice with different treatments containing caerin 1.1/19 were assessed comparatively, including those with/without macrophage depletion. The single-cell RNA sequencing (scRNA-seq) data of previous studies were integrated to further reveal the functions of TAMs with the treatments containing caerin 1.1/1.9. As a comparison, the TAMs of stage I and II cervical cancer patients were analysed using scRNA-seq analysis. We demonstrate that caerin induced tumour clearance is associated with infiltration of tumours by IL-12 secreting Ly6C+F4/80+ macrophages exhibiting enhanced IFN-α response signalling, renders animals resistant to further tumour challenge, which is lost after macrophage depletion. Our results indicate that caerin 1.1/1.9 treatment has great potential in improving current immunotherapy efficacy.

Manipulation of the crosstalk between tumor angiogenesis and immunosuppression in the tumor microenvironment: Insight into the combination therapy of anti-angiogenesis and immune checkpoint blockade

Immunotherapy has been recognized as an effective and important therapeutic modality for multiple types of cancer. Nevertheless, it has been increasing recognized that clinical benefits of immunotherapy are less than expected as evidenced by the fact that only a small population of cancer patients respond favorably to immunotherapy. The structurally and functionally abnormal tumor vasculature is a hallmark of most solid tumors and contributes to an immunosuppressive microenvironment, which poses a major challenge to immunotherapy. In turn, multiple immune cell subsets have profound consequences on promoting neovascularization. Vascular normalization, a promising anti-angiogenic strategy, can enhance vascular perfusion and promote the infiltration of immune effector cells into tumors via correcting aberrant tumor blood vessels, resulting in the potentiation of immunotherapy. More interestingly, immunotherapies are prone to boost the efficacy of various anti-angiogenic therapies and/or promote the morphological and functional alterations in tumor vasculature. Therefore, immune reprograming and vascular normalization appear to be reciprocally regulated. In this review, we mainly summarize how tumor vasculature propels an immunosuppressive phenotype and how innate and adaptive immune cells modulate angiogenesis during tumor progression. We further highlight recent advances of anti-angiogenic immunotherapies in preclinical and clinical settings to solidify the concept that targeting both tumor blood vessels and immune suppressive cells provides an efficacious approach for the treatment of cancer.

Targeting the tumor stroma for cancer therapy

Tumors are comprised of both cancer cells and surrounding stromal components. As an essential part of the tumor microenvironment, the tumor stroma is highly dynamic, heterogeneous and commonly tumor-type specific, and it mainly includes noncellular compositions such as the extracellular matrix and the unique cancer-associated vascular system as well as a wide variety of cellular components including activated cancer-associated fibroblasts, mesenchymal stromal cells, pericytes. All these elements operate with each other in a coordinated fashion and collectively promote cancer initiation, progression, metastasis and therapeutic resistance. Over the past few decades, numerous studies have been conducted to study the interaction and crosstalk between stromal components and neoplastic cells. Meanwhile, we have also witnessed an exponential increase in the investigation and recognition of the critical roles of tumor stroma in solid tumors. A series of clinical trials targeting the tumor stroma have been launched continually. In this review, we introduce and discuss current advances in the understanding of various stromal elements and their roles in cancers. We also elaborate on potential novel approaches for tumor-stroma-based therapeutic targeting, with the aim to promote the leap from bench to bedside.

Construction of PEI-EGFR-PD-L1-siRNA dual functional nano-vaccine and therapeutic efficacy evaluation for lung cancer

BACKGROUND

PD-1/PD-L1 tumor immunotherapy shows effective anticancer in treatment of solid tumors, so PEI lipid nanoparticles (PEI-LNP)/siRNA complex (EPV-PEI-LNP-SiRNA) with the therapeutic function of PD-L1-siRNA and EGFR short peptide/PD-L1 double immune-enhancing function were constructed for the prevention and treatment of EGFR-positive lung cancer in this study.

METHOD

In this study, PEI lipid nanoparticles (PEI-LNP)/siRNA complex (EPV-PEI-LNP-siRNA) with the therapeutic function of PD-L1-siRNA and EGFR short peptide/PD-L1 double immune-enhancing function were constructed for the prevention and treatment of EGFR-positive lung cancer and functional evaluation was conducted.

RESULTS

On the basis of the construction of the composite nano-drug delivery system, the binding capacity, cytotoxicity, apoptosis and uptake capacity of siRNA and EPV-PEI-LNP were tested in vitro, and the downregulation effect of PD-L1 on A549 cancer cells and the cytokine levels of cocultured T cells were tested. Lipid nanoparticles delivered siRNA and EGFR short peptide vaccine to non-small cell lung cancer (NSCLC), increasing tumor invasion and activation of CD8 + T cells. Combination therapy is superior to single target therapy.

CONCLUSION

Our constructed lipid nanoparticles of tumor targeted therapy gene siRNA combination had the ability to target cells in vitro and downregulate the expression of PD-L1, realizing the tumor-specific expression of immune-stimulating cytokines, which is a highly efficient and safe targeted therapy nano-vaccine.

Radiovaccination Strategy for Cancer Treatment Integrating Photodynamic Therapy-Generated Vaccines with Radiotherapy

Therapeutic cancer vaccines have become firmly established as a reliable and proficient form of tumor immunotherapy. They represent a promising approach for substantial advancements in the successful treatment of malignant diseases. One attractive vaccine strategy is using, as the vaccine material, the whole tumor cells treated ex vivo by rapid tumor ablation therapies that instigate stress signaling responses culminating in immunogenic cell death (ICD). One such treatment is photodynamic therapy (PDT). The underlying mechanisms and critical elements responsible for the potency of these vaccines are discussed in this review. Radiotherapy has emerged as a suitable component for the combined therapy protocols with the vaccines. Arguments and prospects for optimizing tumor control using a radiovaccination strategy involving X-ray irradiation plus PDT vaccines are presented, together with the findings supporting its validity.

Anlotinib in recurrent or metastatic endometrial cancer

OBJECTIVE

For recurrent or metastatic endometrial cancer after second-line treatment, therapeutic options are limited. Anlotinib is a new multi-targeted tyrosine kinase inhibitor of tumor angiogenesis and growth. The aim of this study was to explore the efficacy and safety of anlotinib in patients with recurrent or metastatic endometrial cancer.

METHODS

Patients with recurrent or metastatic endometrial cancer who received anlotinib or anlotinib plus pembrolizumab after second-line treatment between July 2017 and October 2020 were analyzed. Objective response rate, disease control rate, progression-free survival, overall survival, and safety were evaluated.

RESULTS

A total of 56 patients were analyzed. The median age was 62 years (range 42-80). The median treatment of anlotinib was 5.9 cycles (range 2-21). The overall objective response rate was 42.9%, and the disease control rate was 75%. 44 (78.6%) patients received anlotinib monotherapy and 12 (21.2%) patients received anlotinib plus pembrolizumab. The objective response rate was 40.9% versus 50% (p=0.52) and the disease control rate was 72.7% versus 83.3% (p=0.59) in the monotherapy group and the combination therapy group, respectively. The median progression-free survival and overall survival from initiation of anlotinib therapy was 6 months (95% CI 4.89 to 7.11) and 13.3 months (95% CI 9.94 to 16.61), respectively. On multivariable Cox analysis, age (>60 vs ≤60 years) was an independent impact factor for both progression-free survival and overall survival, while prior lines of treatment (2 lines vs ≥3 lines) was an independent predictor of progression-free survival. The incidences of grade 3/4 adverse events were hypertension (10.7%), fatigue (7.1%), hand-foot syndrome (7.1%), proteinuria (3.6%), sore throat (3.6%), and hypothyroidism (3.6%).

CONCLUSION

Anlotinib is effective and well tolerated in patients with recurrent or metastatic endometrial cancer. It may be considered a choice for patients younger than 60 years and who have had <3 lines of treatment.

Mesoporous Silica Materials as an Emerging Tool for Cancer Immunotherapy

Cancer immunotherapy has emerged in the past decade as a promising strategy for treating many forms of cancer by stimulating the patient's immune system. Although immunotherapy has achieved some promising results in clinics, more efforts are required to improve the limitations of current treatments related to lack of effective and targeted cancer antigens delivery to immune cells, dose-limiting toxicity, and immune-mediated adverse effects, among others. In recent years, the use of nanomaterials has proven promising to enhance cancer immunotherapy efficacy and reduce side effects. Among nanomaterials, attention has been recently paid to mesoporous silica nanoparticles (MSNs) as a potential multiplatform for enhancing cancer immunotherapy by considering their unique properties, such as high porosity, and good biocompatibility, facile surface modification, and self-adjuvanticity. This review explores the role of MSN and other nano/micro-materials as an emerging tool to enhance cancer immunotherapy, and it comprehensively summarizes the different immunotherapeutic strategies addressed to date by using MSN.

Characterization of MET Exon 14 Skipping Alterations (in NSCLC) and Identification of Potential Therapeutic Targets Using Whole Transcriptome Sequencing

Introduction

Genomic alterations in the juxtamembrane exon 14 splice sites in NSCLC lead to increased MET stability and oncogenesis. We present the largest cohort study of MET Exon 14 (METex14) using whole transcriptome sequencing.

Methods

A total of 21,582 NSCLC tumor samples underwent complete genomic profiling with next-generation sequencing of DNA (592 Gene Panel, NextSeq, whole exome sequencing, NovaSeq) and RNA (NovaSeq, whole transcriptome sequencing). Clinicopathologic information including programmed death-ligand 1 and tumor mutational burden were collected and RNA expression for mutation subtypes and MET amplification were quantified. Immunogenic signatures and potential pathways of invasion were characterized using single-sample gene set enrichment analysis and mRNA gene signatures.

Results

A total of 533tumors (2.47%) with METex14 were identified. The most common alterations were point mutations (49.5%) at donor splice sites. Most alterations translated to increased MET expression, with MET co-amplification resulting in synergistic increase in expression (q < 0.05). Common coalterations were amplifications of MDM2 (19.0% versus 1.8% wild-type [WT]), HMGA2 (13.2% versus 0.98% WT), and CDK4 (10.0% versus 1.5% WT) (q < 0.05). High programmed death-ligand 1 > 50% (52.5% versus 27.3% WT, q < 0.0001) and lower proportion of high tumor mutational burden (>10 mutations per megabase, 8.3% versus 36.7% WT, p < 0.0001) were associated with METex14, which were also enriched in both immunogenic signatures and immunosuppressive checkpoints. Pathways associated with METex14 included angiogenesis and apical junction pathways (q < 0.05).

Conclusions

METex14 splicing alterations and MET co-amplification translated to higher and synergistic MET expression at the transcriptomic level. High frequencies of MDM2 and CDK4 co-amplifications and association with multiple immunosuppressive checkpoints and angiogenic pathways provide insight into potential actionable targets for combination strategies in METex14 NSCLC.

Nucleolin Therapeutic Targeting Decreases Pancreatic Cancer Immunosuppression

Background: The pancreatic ductal adenocarcinoma (PDAC) microenvironment is highly fibrotic and hypoxic, with poor immune cell infiltration. Recently, we showed that nucleolin (NCL) inhibition normalizes tumour vessels and impairs PDAC growth. Methods: Immunocompetent mouse models of PDAC were treated by the pseudopeptide N6L, which selectively inhibits NCL. Tumour-infiltrating immune cells and changes in the tumour microenvironment were analysed. Results: N6L reduced the proportion of regulatory T cells (Tregs) and myeloid-derived suppressor cells (MDSCs) and increased tumour-infiltrated T lymphocytes (TILs) with an activated phenotype. Low-dose anti-VEGFR2 treatment normalized PDAC vessels but did not modulate the immune suppressive microenvironment. RNAseq analysis of N6L-treated PDAC tumours revealed a reduction of cancer-associated fibroblast (CAF) expansion in vivo and in vitro. Notably, N6L treatment decreased IL-6 levels both in tumour tissues and in serum. Treating mPDAC by an antibody blocking IL-6 reduced the proportion of Tregs and MDSCs and increased the amount of TILs, thus mimicking the effects of N6L. Conclusions: These results demonstrate that NCL inhibition blocks the amplification of lymphoid and myeloid immunosuppressive cells and promotes T cell activation in PDAC through a new mechanism of action dependent on the direct inhibition of the tumoral stroma.

Enhancing anti-tumour innate immunity by targeting the DNA damage response and pattern recognition receptors in combination with radiotherapy

Radiotherapy is one of the most effective and frequently used treatments for a wide range of cancers. In addition to its direct anti-cancer cytotoxic effects, ionising radiation can augment the anti-tumour immune response by triggering pro-inflammatory signals, DNA damage-induced immunogenic cell death and innate immune activation. Anti-tumour innate immunity can result from recruitment and stimulation of dendritic cells (DCs) which leads to tumour-specific adaptive T-cell priming and immunostimulatory cell infiltration. Conversely, radiotherapy can also induce immunosuppressive and anti-inflammatory mediators that can confer radioresistance. Targeting the DNA damage response (DDR) concomitantly with radiotherapy is an attractive strategy for overcoming radioresistance, both by enhancing the radiosensitivity of tumour relative to normal tissues, and tipping the scales in favour of an immunostimulatory tumour microenvironment. This two-pronged approach exploits genomic instability to circumvent immune evasion, targeting both hallmarks of cancer. In this review, we describe targetable DDR proteins (PARP (poly[ADP-ribose] polymerase); ATM/ATR (ataxia-telangiectasia mutated and Rad3-related), DNA-PKcs (DNA-dependent protein kinase, catalytic subunit) and Wee1 (Wee1-like protein kinase) and their potential intersections with druggable immunomodulatory signalling pathways, including nucleic acid-sensing mechanisms (Toll-like receptors (TLR); cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) and retinoic acid-inducible gene-I (RIG-I)-like receptors), and how these might be exploited to enhance radiation therapy. We summarise current preclinical advances, recent and ongoing clinical trials and the challenges of therapeutic combinations with existing treatments such as immune checkpoint inhibitors.

Inducing vascular normalization: A promising strategy for immunotherapy

In solid tumors, the vasculature is highly abnormal in structure and function, resulting in the formation of an immunosuppressive tumor microenvironment by limiting immune cells infiltration into tumors. Vascular normalization is receiving much attention as an alternative strategy to anti-angiogenic therapy, and its potential therapeutic targets include signaling pathways, angiogenesis-related genes, and metabolic pathways. Endothelial cells play an important role in the formation of blood vessel structure and function, and their metabolic processes drive blood vessel sprouting in parallel with the control of genetic signals in cancer. The feedback loop between vascular normalization and immunotherapy has been discussed extensively in many reviews. In this review, we summarize the impact of aberrant tumor vascular structure and function on drug delivery, metastasis, and anti-tumor immune responses. In addition, we present evidences for the mutual regulation of immune vasculature. Based on the importance of endothelial metabolism in controlling angiogenesis, we elucidate the crosstalk between endothelial cells and immune cells from the perspective of metabolic pathways and propose that targeting abnormal endothelial metabolism to achieve vascular normalization can be an alternative strategy for cancer treatment, which provides a new theoretical basis for future research on the combination of vascular normalization and immunotherapy.

CD93 is Associated with Glioma-related Malignant Processes and Immunosuppressive Cell Infiltration as an Inspiring Biomarker of Survivance

Previous reports have confirmed the significance of CD93 in the progression of multiple tumors; however, there are few studies examining its immune properties for gliomas. Here, we methodically investigated the pathophysiological characteristics and clinical manifestations of gliomas. Six hundred ninety-nine glioma patients in TCGA along with 325 glioma patients in CGGA were correspondingly collected for training and validating. We analyzed and visualized total statistics using RStudio. One-way ANOVA and Student's t-test were used to assess groups' differences. All differences were considered statistically significant at the level of P < 0.05. CD93 markedly upregulated among HGG, MGMT promoter unmethylated subforms, IDH wild forms, 1p19q non-codeletion subforms, and mesenchyme type gliomas. ROC analysis illustrated the favorable applicability of CD93 in estimating mesenchyme subform. Kaplan-Meier curves together with multivariable Cox analyses upon survivance identified high-expression CD93 as a distinct prognostic variable for glioma patients. GO analysis of CD93 documented its predominant part in glioma-related immunobiological processes and inflammation responses. We examined the associations of CD93 with immune-related meta-genes, and CD93 positively correlated with HCK, LCK, MHC I, MHC II, STAT1 and IFN, while adverse with IgG. Association analyses between CD93 and gliomas-infiltrating immunocytes indicated that the infiltrating degrees of most immunocytes exhibited positive correlations with CD93, particularly these immunosuppressive subsets such as TAM, Treg, and MDSCs. CD93 is markedly associated with adverse pathology types, unfavorable survival, and immunosuppressive immunocytes infiltration among gliomas, thus identifying CD93 as a practicable marker and a promising target for glioma-based precise diagnosis and therapeutic strategies.

IL-8 and its role as a potential biomarker of resistance to anti-angiogenic agents and immune checkpoint inhibitors in metastatic renal cell carcinoma

The therapeutic armamentarium of metastatic Renal Cell Carcinoma (mRCC) has consistently expanded in recent years, with the introduction of VEGF/VEGFR (Vascular Endothelial Growth Factor/Vascular Endothelial Growth Factor Receptor) inhibitors, mTOR (mammalian Target Of Rapamycin) inhibitors and Immune Checkpoint (IC) inhibitors. Currently, for the first-tline treatment of mRCC it is possible to choose between a VEGFR-TKI (VEGFR-Tyrosine Kinase Inhibitor) monotherapy, an ICI-ICI (Immune Checkpoint Inhibitor) combination and an ICI-VEGFRTKI combination. However, a consistent part of patients does not derive benefit from first-line therapy with ICIs; moreover, the use of combination regimens exposes patients to significant toxicities. Therefore, there is a critical need to develop prognostic and predictive biomarkers of response to VEGFR-TKIs and ICIs, and measurement of serum IL-8 is emerging as a potential candidate in this field. Recent retrospective analyses of large phase II and phase III trials found that elevated baseline serum IL-8 correlated with higher levels of tumor and circulating immunosuppressive myeloid cells, decreased T cell activation and poor response to treatment. These findings must be confirmed in prospective clinical trials; however, they provide evidence for a potential use of serum IL-8 as biomarker of resistance to VEGFR-TKIs and ICIs. Considering the amount of new agents and treatment regimens which are transforming the management of metastatic renal cell carcinoma, serum IL-8 could become a precious resource in tailoring the best therapy for each individual patient with the disease.

Novel myeloma patient-derived xenograft models unveil the potency of anlotinib to overcome bortezomib resistance

Multiple myeloma (MM) remains a common hematologic malignancy with a 10-year survival rate below 50%, which is largely due to disease relapse and resistance. The lack of a simple and practical approach to establish myeloma patient-derived xenograft (PDX) hampers translational myeloma research. Here, we successfully developed myeloma PDXs by subcutaneous inoculation of primary mononuclear cells from MM patients following series tumor tissue transplantations. Newly established myeloma PDXs retained essential cellular features of MM and recapitulated their original drug sensitivities as seen in the clinic. Notably, anlotinib therapy significantly suppressed the growth of myeloma PDXs even in bortezomib-resistant model. Anlotinib treatments polarized tumor-associated macrophages from an M2- to an M1-like phenotype, decreased tumor vascular function, and accelerated cell apoptosis in myeloma PDXs. Our preclinical work not only unveiled the potency of anlotinib to overcome bortezomib resistance, but also provided a more practical way to establish MM PDX to facilitate myeloma research.

Host-Related Factors as Targetable Drivers of Immunotherapy Response in Non-Small Cell Lung Cancer Patients

Despite some significant therapeutic breakthroughs leading to immunotherapy, a high percentage of patients with non-small cell lung cancer (NSCLC) do not respond to treatment on relapse, thus experiencing poor prognosis and survival. The unsatisfying results could be related to the features of the tumor immune microenvironment and the dynamic interactions between a tumor and immune infiltrate. Host-tumor interactions strongly influence the course of disease and response to therapies. Thus, targeting host-associated factors by restoring their physiologic functions altered by the presence of a tumor represents a new therapeutic approach to control tumor development and progression. In NSCLC, the immunogenic tumor balance is shifted negatively toward immunosuppression due to the release of inhibitory factors as well as the presence of immunosuppressive cells. Among these cells, there are myeloid-derived suppressor cells, regulatory T cells that can generate a tumor-permissive milieu by reprogramming the cells of the hosts such as tumor-associated macrophages, tumor-associated neutrophils, natural killer cells, dendritic cells, and mast cells that acquire tumor-supporting phenotypes and functions. This review highlights the current knowledge of the involvement of host-related factors, including innate and adaptive immunity in orchestrating the tumor cell fate and the primary resistance mechanisms to immunotherapy in NSCLC. Finally, we discuss combinational therapeutic strategies targeting different aspects of the tumor immune microenvironment (TIME) to prime the host response. Further research dissecting the characteristics and dynamic interactions within the interface host-tumor is necessary to improve a patient fitness immune response and provide answers regarding the immunotherapy efficacy, with the aim to develop more successful treatments for NSCLC.

A Profile of Avelumab Plus Axitinib in the Treatment of Renal Cell Carcinoma

Until recently, the approved first-line treatment for metastatic RCC (mRCC) consisted of tyrosine kinase inhibitors (TKI) targeting the vascular endothelial growth factor receptors (VEGFR) monotherapy. The landscape of first-line treatment has been transformed in the last few years with the advent of immune checkpoint inhibitors (ICI) or VEGFR TKI plus ICI combinations. This article focuses on the profile of one of these ICI plus VEGFR TKI combination, avelumab plus axitinib. We detail the characteristics of each drug separately, and then we explore the rationale for their association, its efficacy and the resulting toxicity. Finally, we examine the factors associated with avelumab plus axitinib outcomes, and their impact on therapeutic strategy.

The Role of Imaging Biomarkers to Guide Pharmacological Interventions Targeting Tumor Hypoxia

Hypoxia is a common feature of solid tumors that contributes to angiogenesis, invasiveness, metastasis, altered metabolism and genomic instability. As hypoxia is a major actor in tumor progression and resistance to radiotherapy, chemotherapy and immunotherapy, multiple approaches have emerged to target tumor hypoxia. It includes among others pharmacological interventions designed to alleviate tumor hypoxia at the time of radiation therapy, prodrugs that are selectively activated in hypoxic cells or inhibitors of molecular targets involved in hypoxic cell survival (i.e., hypoxia inducible factors HIFs, PI3K/AKT/mTOR pathway, unfolded protein response). While numerous strategies were successful in pre-clinical models, their translation in the clinical practice has been disappointing so far. This therapeutic failure often results from the absence of appropriate stratification of patients that could benefit from targeted interventions. Companion diagnostics may help at different levels of the research and development, and in matching a patient to a specific intervention targeting hypoxia. In this review, we discuss the relative merits of the existing hypoxia biomarkers, their current status and the challenges for their future validation as companion diagnostics adapted to the nature of the intervention.

Low-dose X-ray irradiation combined with FAK inhibitors improves the immune microenvironment and confers sensitivity to radiotherapy in pancreatic cancer

Radiation therapy offers limited clinical benefits for patients with pancreatic cancer, partly as a result of the predominantly immunosuppressive microenvironment characteristic of this specific type of cancer. A large number of abnormal blood vessels and high-density fibrous matrices in pancreatic cancer will lead to hypoxia within tumor tissue and hinder immune cell infiltration. We used low-dose X-ray irradiation, also known as low-dose radiation therapy (LDRT), to normalize the blood vessels in pancreatic cancer, while simultaneously administering an inhibitor of focal adhesion kinase (FAK) to reduce pancreatic cancer fibrosis. We found that this treatment successfully reduced pancreatic cancer hypoxia, increased immune cell infiltration, and increased sensitivity to radiation therapy for pancreatic cancer.

Dendritic Cell-Based Immunotherapy in Hot and Cold Tumors

Dendritic cells mediate innate and adaptive immune responses and are directly involved in the activation of cytotoxic T lymphocytes that kill tumor cells. Dendritic cell-based cancer immunotherapy has clinical benefits. Dendritic cell subsets are diverse, and tumors can be hot or cold, depending on their immunogenicity; this heterogeneity affects the success of dendritic cell-based immunotherapy. Here, we review the ontogeny of dendritic cells and dendritic cell subsets. We also review the characteristics of hot and cold tumors and briefly introduce therapeutic trials related to hot and cold tumors. Lastly, we discuss dendritic cell-based cancer immunotherapy in hot and cold tumors.

Combination of tumor vessel normalization and immune checkpoint blockade for breast cancer treatment via multifunctional nanocomplexes

Tumor vessel normalization can alleviate hypoxia, reduce the intratumoral infiltration of immunosuppressive cells and increase the intratumoral infiltration of immune effector cells (CD8⁺ T cells), further reversing the immunosuppressive microenvironment. Here, nanocomplexes (lipo/St@FA-COSA/BMS-202) which can accurately deliver drugs to tumor tissues and release different drugs at different sites with different rates were prepared to combine tumor vessel normalization with immune checkpoint blockade. The results of drug release in vitro showed that in a pH 6.5 release medium, lipo/St@FA-COSA/BMS-202 rapidly released the vascular normalizing drug (sunitinib, St) and slowly released the PD-1/PD-L1-blocking drug (BMS-202). The results of in vivo experiments showed that the rapidly released St normalized tumor vessels and formed an immunosupportive microenvironment which improved the anti-tumor efficacy of BMS-202. In conclusion, the drug delivery strategy significantly inhibited tumor growth and had excellent anti-tumor efficacy, which can provide a potential approach for effective tumor treatment.

Vascular endothelial growth factor receptor 2 expression and immunotherapy efficacy in non-small cell lung cancer

It is unclear whether tumor vascular endothelial growth factor receptor 2 expression affects the therapeutic efficacy of immune‐checkpoint inhibitors and antiangiogenic agents. This retrospective, multicenter study included patients with advanced non–small cell lung cancer who were treated with immune‐checkpoint inhibitors. We constructed tissue microarrays and performed immunohistochemistry with an anti‐vascular endothelial growth factor receptor 2 antibody. We analyzed immune and tumor cell staining separately in order to determine their correlation with the objective response rate, progression‐free survival, and overall survival in patients receiving immune‐checkpoint inhibitors. Of 364 patients, 37 (10%) expressed vascular endothelial growth factor receptor 2 in immune cells and 165 (45%) in tumor cells. The objective response rate, progression‐free survival, and overall survival were significantly worse in patients treated with immune checkpoint inhibitor monotherapy who expressed vascular endothelial growth factor receptor 2 in immune cells than those who did not (10% vs 30%, p = 0.028; median = 2.2 vs 3.6 months, p = 0.012; median = 7.9 vs 17.0 months, p = 0.049, respectively), while there was no significant difference based on tumor cell expression (24% vs 30%, p = 0.33; median = 3.1 vs 3.5 months, p = 0.55; median = 13.6 vs 16.8 months, p = 0.31). There was no significant difference in overall survival between patients treated with and without antiangiogenic agents in any treatment period based on vascular endothelial growth factor receptor 2 expression. Immune checkpoint inhibitor efficacy was limited in patients expressing vascular endothelial growth factor receptor 2 in immune cells.

Safety and efficacy of nivolumab plus bevacizumab, paclitaxel for HER2-negative metastatic breast cancer: Primary results and biomarker data from a phase 2 trial (WJOG9917B)

BACKGROUND

Preclinical models revealed potential synergistic effects of programmed cell death-1 inhibitors and anti-vascular endothelial growth factor (VEGF) antibodies. Therefore, we investigated the use of nivolumab, bevacizumab, and paclitaxel triple therapy for metastatic breast cancer.

METHODS

This phase 2, multicentre, single-arm study (NEWBEAT) investigated the safety and efficacy of first-line nivolumab, paclitaxel, and bevacizumab in patients with human epidermal growth factor receptor 2-negative metastatic breast cancer, regardless of programmed cell death-ligand 1 expression. The primary end-point was objective response rate. Key secondary end-points included progression-free survival, overall survival, and toxicities. A biomarker study evaluated tumour programmed cell death-ligand 1 expression and serum VEGF-A levels.

RESULTS

Between February 2018 and October 2018, 57 patients were enrolled. An objective response rate was seen in 39/56 patients (70%, 95% confidence interval [CI]: 55.9-81.2%), meeting the primary end-point. The objective response rate was 74% in patients with hormone receptor-positive breast cancer versus 59% in patients with triple-negative breast cancer. The median progression-free survival and overall survival were 14.0 (95% CI 11.0-16.3) and 32.5 (95% CI 26.0-not evaluable) months, respectively (median follow-up: 29.5 months). Grade 3/4 adverse drug reactions occurred in 33 of 57 patients (58%). There were no grade 5 adverse events. Immune-related adverse events occurred in 43 of 57 patients (75%), with grade 3/4 events in eight patients (14%). Biomarker analysis showed that tumour programmed cell death-ligand 1 expression was not correlated with the efficacy of triple therapy. Efficacy outcomes were similar between the serum VEGF-high and VEGF-low groups.

CONCLUSIONS

First-line nivolumab, bevacizumab, and paclitaxel therapy showed promising efficacy and manageable toxicity in patients with human epidermal growth factor receptor 2-negative metastatic breast cancer.

Impact of Neoadjuvant Bevacizumab on Neuroradiographic Response and Histological Findings Related to Tumor Stemness and the Hypoxic Tumor Microenvironment in Glioblastoma: Paired Comparison Between Newly Diagnosed and Recurrent Glioblastomas

Background

Previously, we reported that bevacizumab (Bev) produces histological and neuroradiographic alterations including changes in tumor oxygenation, induction of an immunosupportive tumor microenvironment, and inhibition of stemness. To confirm how those effects vary during Bev therapy, paired samples from the same patients with newly diagnosed glioblastoma (GBM) who received preoperative neoadjuvant Bev (neoBev) were investigated with immunohistochemistry before and after recurrence.

Methods

Eighteen samples from nine patients with newly diagnosed GBM who received preoperative neoBev followed by surgery and chemoradiotherapy and then autopsy or salvage surgery after recurrence were investigated. The expression of carbonic anhydrase 9 (CA9), hypoxia-inducible factor-1 alpha (HIF-1α), nestin, and Forkhead box M1 (FOXM1) was evaluated with immunohistochemistry.

For comparison between neoBev and recurrent tumors, we divided the present cohort into two groups based on neuroradiographic response: good and poor responders (GR and PR, respectively) to Bev were defined by the tumor regression rate on T1-weighted images with gadolinium enhancement (T1Gd) and fluid-attenuated inversion recovery images. Patterns of recurrence after Bev therapy were classified as cT1 flare-up and T2-diffuse/T2-circumscribed. Furthermore, we explored the possibility of utilizing FOXM1 as a biomarker of survival in this cohort.

Results

A characteristic “pseudo-papillary”-like structure containing round-shaped tumor cells clustered adjacent to blood vessels surrounded by spindle-shaped tumor cells was seen only in recurrent tumors. Tumor cells at the outer part of the “pseudo-papillary” structure were CA9-positive (CA9+)/HIF-1α+, whereas cells at the inner part of this structure were CA9−/HIF-1α+ and nestin+/FOXM1+. CA9 and HIF-1α expression was lower in T1Gd-GR and decreased in the “T2-circumscribed/T2-diffuse” pattern compared with the “T1 flare-up” pattern, suggesting that tumor oxygenation was frequently observed in T1Gd-GR in initial tumors and in the “T2-circumscribed/T2-diffuse” pattern in recurrent tumors. FOXM1 low-expression tumors tended to have a better prognosis than that of FOXM1 high-expression tumors.

Conclusion

A “pseudo-papillary” structure was seen in recurrent GBM after anti-vascular endothelial growth factor therapy. Bev may contribute to tumor oxygenation, leading to inhibition of stemness and correlation with a neuroimaging response during Bev therapy. FOXM1 may play a role as a biomarker of survival during Bev therapy.

Blood Stasis Syndrome Accelerates the Growth and Metastasis of Breast Cancer by Promoting Hypoxia and Immunosuppressive Microenvironment in Mice

Blood stasis syndromes (BSSs) are closely related to the occurrence and development of tumors, although the mechanism is still unclear. This study was aimed at exploring the effect and mechanism underlying different BSSs on tumor growth and metastasis. We established four BSS mouse models bred with breast cancer: qi deficiency and blood stasis (QDBS), cold coagulation blood stasis (CCBS), heat toxin and blood stasis (HTBS), and qi stagnation and blood stasis (QSBS). The results showed that microcirculation in the lower limb, abdominal wall, and tumor in situ decreased by varying degrees in the BSS groups. In addition, BSS promoted tumor growth and lung metastasis. The ratio of regulatory T cells in the tumor microenvironment was downregulated. Moreover, hypoxia-inducible factor 1-α, Wnt1, β-catenin, vascular endothelial growth factor, and Cyclin D1 levels increased in the tumors of BSS mice. In conclusion, BSS not only promoted the formation of a hypoxic and immunosuppressive microenvironment but also promoted the neovascularization.

Immune Mechanisms of Resistance to Cediranib in Ovarian Cancer

This article investigates mechanisms of resistance to the VEGF receptor inhibitor cediranib in high-grade serous ovarian cancer (HGSOC), and defines rational combination therapies. We used three different syngeneic orthotopic mouse HGSOC models that replicated the human tumor microenvironment (TME). After 4 to 5 weeks treatment of established tumors, cediranib had antitumor activity with increased tumor T-cell infiltrates and alterations in myeloid cells. However, continued cediranib treatment did not change overall survival or the immune microenvironment in two of the three models. Moreover, treated mice developed additional peritoneal metastases not seen in controls. Cediranib-resistant tumors had intrinsically high levels of IL6 and JAK/STAT signaling and treatment increased endothelial STAT3 activation. Combination of cediranib with a murine anti-IL6 antibody was superior to monotherapy, increasing mouse survival, reducing blood vessel density, and pSTAT3, with increased T-cell infiltrates in both models. In a third HGSOC model, that had lower inherent IL6 JAK/STAT3 signaling in the TME but high programmed cell death protein 1 (PD-1) signaling, long-term cediranib treatment significantly increased overall survival. When the mice eventually relapsed, pSTAT3 was still reduced in the tumors but there were high levels of immune cell PD-1 and Programmed death-ligand 1. Combining cediranib with an anti-PD-1 antibody was superior to monotherapy in this model, increasing T cells and decreasing blood vessel densities. Bioinformatics analysis of two human HGSOC transcriptional datasets revealed distinct clusters of tumors with IL6 and PD-1 pathway expression patterns that replicated the mouse tumors. Combination of anti-IL6 or anti-PD-1 in these patients may increase activity of VEGFR inhibitors and prolong disease-free survival.

Crosstalk between angiogenesis and immune regulation in the tumor microenvironment

Cancer creates a complex tumor microenvironment (TME) composed of immune cells, stromal cells, blood vessels, and various other cellular and extracellular elements. It is essential for the development of anti-cancer combination therapies to understand and overcome this high heterogeneity and complexity as well as the dynamic interactions between them within the TME. Recent treatment strategies incorporating immune-checkpoint inhibitors and anti-angiogenic agents have brought many changes and advances in clinical cancer treatment. However, there are still challenges for immune suppressive tumors, which are characterized by a lack of T cell infiltration and treatment resistance. In this review, we will investigate the crosstalk between immunity and angiogenesis in the TME. In addition, we will look at strategies designed to enhance anti-cancer immunity, to convert "immune suppressive tumors" into "immune activating tumors," and the mechanisms by which these strategies enhance effector immune cell infiltration.

Acquired αSMA Expression in Pericytes Coincides with Aberrant Vascular Structure and Function in Pancreatic Ductal Adenocarcinoma

The subpopulations of tumor pericytes undergo pathological phenotype switching, affecting their normal function in upholding structural stability and cross-communication with other cells. In the case of pancreatic ductal adenocarcinoma (PDAC), a significant portion of blood vessels are covered by an α-smooth muscle actin (αSMA)-expressing pericyte, which is normally absent from capillary pericytes. The Desmin^lowαSMA^high phenotype was significantly correlated with intratumoral hypoxia and vascular leakiness. Using an in vitro co-culture system, we demonstrated that cancer cell-derived exosomes could induce ectopic αSMA expression in pericytes. Exosome-treated αSMA⁺ pericytes presented altered pericyte markers and an acquired immune-modulatory feature. αSMA⁺ pericytes were also linked to morphological and biomechanical changes in the pericyte. The PDAC exosome was sufficient to induce αSMA expression by normal pericytes of the healthy pancreas in vivo, and the vessels with αSMA⁺ pericytes were leaky. This study demonstrated that tumor pericyte heterogeneity could be dictated by cancer cells, and a subpopulation of these pericytes confers a pathological feature.

Mechanical loading of intraluminal pressure mediates wound angiogenesis by regulating the TOCA family of F-BAR proteins

Angiogenesis is regulated in coordinated fashion by chemical and mechanical cues acting on endothelial cells (ECs). However, the mechanobiological mechanisms of angiogenesis remain unknown. Herein, we demonstrate a crucial role of blood flow-driven intraluminal pressure (IP) in regulating wound angiogenesis. During wound angiogenesis, blood flow-driven IP loading inhibits elongation of injured blood vessels located at sites upstream from blood flow, while downstream injured vessels actively elongate. In downstream injured vessels, F-BAR proteins, TOCA1 and CIP4, localize at leading edge of ECs to promote N-WASP-dependent Arp2/3 complex-mediated actin polymerization and front-rear polarization for vessel elongation. In contrast, IP loading expands upstream injured vessels and stretches ECs, preventing leading edge localization of TOCA1 and CIP4 to inhibit directed EC migration and vessel elongation. These data indicate that the TOCA family of F-BAR proteins are key actin regulatory proteins required for directed EC migration and sense mechanical cell stretching to regulate wound angiogenesis.

Chemical and mechanical cues coordinately regulate angiogenesis. Here, the authors show that blood flow-driven intraluminal pressure regulates wound angiogenesis. Findings indicate that TOCA family of F-BAR proteins act as actin regulators required for endothelial cell migration and sense mechanical cell stretching to regulate wound angiogenesis.

Current status and advances of immunotherapy in nasopharyngeal carcinoma

The general immune landscape of nasopharyngeal carcinoma (NPC) renders immunotherapy suitable for patients with NPC. Immune checkpoint inhibitors (ICIs) based on programmed death-1/programmed death ligand-1 (PD-1/PD-L1) blockade have made a breakthrough with the approval of PD-1 inhibitor for refractory recurrence and/or metastatic (R/M NPC) and the approval of PD-1 inhibitor in combination with gemcitabine and cisplatin as first line for R/M NPC in 2021 in China. The incorporation of ICIs into the treatment paradigms of NPC has become a clinical hot spot and many prospective clinical studies are ongoing. In this review, we provide a comprehensive overview of the rationale for immunotherapy in NPC and current status, advances and challenges of immunotherapy in NPC based on published clinical data, and ongoing trials. We focus on the clinical application and advances of PD-1 inhibitor monotherapy and its combination with chemotherapy and summarize the clinical explorations of other immunotherapy approaches, for example, combination of PD-1/PD-L1 inhibitors with antiangiogenic inhibitor with molecular targeted agents, cancer vaccines, adaptive immunotherapy, and new ICI agents beyond PD-1/PD-L1 inhibitors in R/M NPC. We also describe the clinical studies’ status and challenges of ICIs-based immunomodulatory strategies in local advanced NPC and pay attention to the biomarker application for personalized immunotherapy of NPC in the hope to provide insights for clinical practice and future clinical studies.

Paclitaxel-carboplatin and bevacizumab combination with maintenance bevacizumab therapy for metastatic, recurrent, and persistent uterine cervical cancer: An open-label multicenter phase II trial (JGOG1079)

OBJECTIVE

This multicenter, open-label, phase II study aimed to evaluate the efficacy and safety of paclitaxel-carboplatin, bevacizumab, and bevacizumab-based maintenance therapy for metastatic, recurrent, and persistent uterine cervical cancer.

METHODS

Patients with measurable diseases that were not adapted to regional therapies, such as surgery or radiotherapy, and were systematic chemotherapy-naïve were eligible. The participants received paclitaxel (175 mg/m²), carboplatin (AUC 5), and bevacizumab (15 mg/m²) every three weeks until disease progression or unacceptable adverse events occurred. The primary endpoint was progression-free survival (PFS). The secondary endpoints were overall response rate (ORR), overall survival (OS), safety, and time to treatment failure.

RESULTS

Sixty-nine patients were analyzed using our protocol. The median paclitaxel- carboplatin therapy duration was six cycles; 40% of patients received bevacizumab maintenance therapy. The median PFS was 11.3 months. The median OS was not reached; the median time to treatment failure was 5.9 months. The ORR was 79.7% [95% confidence interval (CI) 63.8-88.4]; 16 patients (23.2%) showed complete response (CR) and 39 patients (56.5%) showed partial response (PR). The median PFS was 14.3 months (95% CI 7.3-17 months) for the 25 patients who received maintenance therapy and 7.4 months (95% CI 6.1-11 months) for nonrecipients (p = 0.0449). Gastrointestinal perforation/fistulas occurred in four patients (5.6%), all of whom had a history of radiation therapy.

CONCLUSIONS

Paclitaxel-carboplatin and bevacizumab therapy is an acceptable and tolerable treatment for advanced or recurrent cervical cancer.

Efficacy and Safety of TACE Combined With Lenvatinib Plus PD-1 Inhibitors Compared With TACE Alone for Unresectable Hepatocellular Carcinoma Patients: A Prospective Cohort Study

Purpose

To compare the efficacy and safety of the combination of transcatheter arterial chemoembolization (TACE), Lenvatinib, and programmed cell death protein-1 (PD-1) inhibitors (combination group) with TACE (TACE group) in the treatment of patients with unresectable hepatocellular carcinoma (uHCC).

Methods

We consecutively enrolled 110 patients with uHCC in this prospective cohort study, with 56 patients receiving combination treatment and 54 patients receiving TACE from November 2017 to September 2020. The differences in tumor response, survival benefit, and adverse events (AEs) were compared between the two groups. Factors affecting survival were identified via Cox regression analysis.

Results

Compared with the TACE group, the combination group had a higher objective response rate (ORR) (67.9% vs. 29.6%, p < 0.001), longer median progression-free survival (mPFS) (11.9 vs. 6.9 months, P = 0.003) and overall survival (mOS) (23.9 vs. 15.3 months, p < 0.001). Multivariate analysis showed that the neutrophil-to-lymphocyte ratio (NLR) and the treatment option were independent factors associated with the PFS and OS. Further subgroup analysis showed that patients with low NLR (≤median 3.11) receiving combination therapy had better mPFS (20.1 vs. 6.2 months, P < 0.001) and mOS (28.9 vs. 15.2 months, P < 0.001) than those receiving TACE, while no obvious difference in PFS or OS was observed between the two groups in patients with high NLR (> 3.11). There were no unexpected toxicities in the combination group.

Conclusion

Compared with TACE, the combination treatment demonstrated an improved clinical efficacy and manageable safety profile in patients with uHCC. Combination treatment showed better therapeutic efficacy in patients with low NLR; therefore, this ratio could be used to identify patients who will benefit from this treatment.

NLGP regulates RGS5-TGFβ axis to promote pericyte-dependent vascular normalization during restricted tumor growth

Altered RGS5-associated intracellular pericyte signaling and its abnormal crosstalk with endothelial cells (ECs) result chaotic tumor-vasculature, prevent effective drug delivery, promote immune-evasion and many more to ensure ultimate tumor progression. Moreover, the frequency of lethal-RGS5^high  pericytes within tumor was found to increase with disease progression, which signifies the presence of altered cell death pathway within tumor microenvironment (TME). In this study, we checked whether and how neem leaf glycoprotein (NLGP)-immunotherapy-mediated tumor growth restriction is associated with modification of pericytes' signaling, functions and its interaction with ECs. Analysis of pericytes isolated from tumors of NLGP treated mice suggested that NLGP treatment promotes apoptosis of NG2⁺ RGS5^high -fuctionally altered pericytes by downregulating intra-tumoral TGFβ, along with maintenance of more matured RGS5^neg  pericytes. NLGP-mediated inhibition of TGFβ within TME rescues binding of RGS5 with Gαi and thereby termination of PI3K-AKT mediated survival signaling by downregulating Bcl2 and initiating pJNK mediated apoptosis. Limited availability of TGFβ also prevents complex-formation between RGS5 and Smad2 and rapid RGS5 nuclear translocation to mitigate alternate immunoregulatory functions of RGS5^high  tumor-pericytes. We also observed binding of Ang1 from pericytes with Tie2 on ECs in NLGP-treated tumor, which support re-association of pericytes with endothelium and subsequent vessel stabilization. Furthermore, NLGP-therapy- associated RGS5 deficiency relieved CD4⁺  and CD8⁺ T cells from anergy by regulating 'alternate-APC-like' immunomodulatory characters of tumor-pericytes. Taken together, present study described the mechanisms of NLGP's effectiveness in normalizing tumor-vasculature by chiefly modulating pericyte-biology and EC-pericyte interactions in tumor-host to further strengthen its translational potential as single modality treatment.

Four-quadrant fast compressive tracking of breast ultrasound videos for computer-aided response evaluation of neoadjuvant chemotherapy in mice

BACKGROUND AND OBJECTIVE

Neoadjuvant chemotherapy (NAC) is a valuable treatment approach for locally advanced breast cancer. Contrast-enhanced ultrasound (CEUS) potentially enables the assessment of therapeutic response to NAC. In order to evaluate the response accurately, quantitatively and objectively, a method that can effectively compensate motions of breast cancer in CEUS videos is urgently needed.

METHODS

We proposed the four-quadrant fast compressive tracking (FQFCT) approach to automatically perform CEUS video tracking and compensation for mice undergoing NAC. The FQFCT divided a tracking window into four smaller windows at four quadrants of a breast lesion and formulated the tracking at each quadrant as a binary classification task. After the FQFCT of breast cancer videos, the quantitative features of CEUS including the mean transit time (MTT) were computed. All mice showed a pathological response to NAC. The features between pre- (day 1) and post-treatment (day 3 and day 5) in these responders were statistically compared.

RESULTS

When we tracked the CEUS videos of mice with the FQFCT, the average tracking error of FQFCT was 0.65 mm, reduced by 46.72% compared with the classic fast compressive tracking method (1.22 mm). After compensation with the FQFCT, the MTT on day 5 of the NAC was significantly different from the MTT before NAC (day 1) (p = 0.013).

CONCLUSIONS

The FQFCT improves the accuracy of CEUS video tracking and contributes to the computer-aided response evaluation of NAC for breast cancer in mice.

Case Report: Complete Remission With Anti-PD-1 and Anti-VEGF Combined Therapy of a Patient With Metastatic Primary Splenic Angiosarcoma

Primary splenic angiosarcoma (PSA) is a rare malignancy with poor prognosis. At present, little study is available on immunotherapy in PSA. Here, we report a case of a patient with metastatic PSA who was treated with programmed death-1 (PD-1) inhibitors and vascular endothelial growth factor (VEGF) tyrosine kinase inhibitors combined therapy and achieved complete response (CR). The patient was a 57−year−old woman with three liver metastases. She was treated with seven cycles of toripalimab plus anlotinib. Programmed death-ligand 1 (PD-L1) immunohistochemistry and next-generation sequencing was performed, and the PD-L1 tumor proportion score was 75%. Finally, she achieved CR after six cycles of the combined therapy regimen. No serious adverse events were detected. To the best of our knowledge, this is the first clinical evidence that anti-PD-1 plus anti-VEGF therapy might be a promising option for patients with metastatic PSA. However, more clinical trials are needed to verify this conclusion.

The Research Progress of Antiangiogenic Therapy, Immune Therapy and Tumor Microenvironment

Anti-angiogenesis therapy, a promising strategy against cancer progression, is limited by drug-resistance, which could be attributed to changes within the tumor microenvironment. Studies have increasingly shown that combining anti-angiogenesis drugs with immunotherapy synergistically inhibits tumor growth and progression. Combination of anti-angiogenesis therapy and immunotherapy are well-established therapeutic options among solid tumors, such as non-small cell lung cancer, hepatic cell carcinoma, and renal cell carcinoma. However, this combination has achieved an unsatisfactory effect among some tumors, such as breast cancer, glioblastoma, and pancreatic ductal adenocarcinoma. Therefore, resistance to anti-angiogenesis agents, as well as a lack of biomarkers, remains a challenge. In this review, the current anti-angiogenesis therapies and corresponding drug-resistance, the relationship between tumor microenvironment and immunotherapy, and the latest progress on the combination of both therapeutic modalities are discussed. The aim of this review is to discuss whether the combination of anti-angiogenesis therapy and immunotherapy can exert synergistic antitumor effects, which can provide a basis to exploring new targets and developing more advanced strategies.

Injectable Hydrogel as a Unique Platform for Antitumor Therapy Targeting Immunosuppressive Tumor Microenvironment

Cancer immunotherapy can boost the immune response of patients to eliminate tumor cells and suppress tumor metastasis and recurrence. However, immunotherapy resistance and the occurrence of severe immune-related adverse effects are clinical challenges that remain to be addressed. The tumor microenvironment plays a crucial role in the therapeutic efficacy of cancer immunotherapy. Injectable hydrogels have emerged as powerful drug delivery platforms offering good biocompatibility and biodegradability, minimal invasion, convenient synthesis, versatility, high drug-loading capacity, controlled drug release, and low toxicity. In this review, we summarize the application of injectable hydrogels as a unique platform for targeting the immunosuppressive tumor microenvironment.

Case Report: Toripalimab Combined With Anlotinib in a Patient With Metastatic Upper Tract Urothelial Carcinoma After Pembrolizumab Failure

Urothelial carcinoma is the most common primary upper tract urinary carcinoma. If surgery, chemotherapy, and immunotherapy fail, the prognosis for upper tract urinary carcinoma is extremely poor. Immunotherapy combined with antiangiogenesis therapy is a new therapeutic regimen with a synergistic antitumor effect. We present a case of metastatic upper tract urinary carcinoma in which the patient underwent surgery and treatment with gemcitabine combined with platinum-based chemotherapy. Radiotherapy and second-line immunotherapy (pembrolizumab) were administered after the cancer had progressed to the left lymph node of the abdominal aorta in the umbilical plane. However, the patient developed liver metastases while being treated with pembrolizumab. He was administered off-label immunotherapy (toripalimab) combined with antiangiogenesis therapy (anlotinib) and achieved a long-term clinical response for over 25 months. Toripalimab combined with anlotinib has potential therapeutic value for locally advanced or metastatic upper tract urinary carcinoma in patients who had previously received platinum-based chemotherapy and had disease progression or after treatment with a PD-1 inhibitor.

Targeting Angiogenesis in Squamous Cell Carcinoma of the Head and Neck: Opportunities in the Immunotherapy Era

Simple Summary

Therapies for squamous cell carcinomas of the head and neck (SCCHN) have been rapidly evolving, initially with the inclusion of immunotherapy, but more recently with the consideration of anti-angiogenic therapies. Recent preclinical and clinical data reveal a strong correlation between vascular endothelial growth factor (VEGF) and the progression of SCCHN, with nearly 90% of these malignancies expressing VEGF. Our review article not only elaborates on the utility of anti-VEGF therapies on SCCHN but also its interaction with the immune environment. Furthermore, we detailed the current data on immunotherapies targeting SCCHN and how this could be coupled with anti-angiogenics therapies.

Abstract

Despite the lack of approved anti-angiogenic therapies in squamous cell carcinoma of the head and neck (SCCHN), preclinical and more recent clinical evidence support the role of targeting the vascular endothelial growth factor (VEGF) in this disease. Targeting VEGF has gained even greater interest following the recent evidence supporting the role of immunotherapy in the management of advanced SCCHN. Preclinical evidence strongly suggests that VEGF plays a role in promoting the growth and progression of SCCHN, and clinical evidence exists as to the value of combining this strategy with immunotherapeutic agents. Close to 90% of SCCHNs express VEGF, which has been correlated with a worse clinical prognosis and an increased resistance to chemotherapeutic agents. As immunotherapy is currently at the forefront of the management of advanced SCCHN, revisiting the rationale for targeting angiogenesis in this disease has become an even more attractive proposition.