Combining Immune Checkpoint Inhibitors with Anti-Angiogenic Agents

Survival strategies: How tumor hypoxia microenvironment orchestrates angiogenesis

During tumor development, the tumor itself must continuously generate new blood vessels to meet their growth needs while also allowing for tumor invasion and metastasis. One of the most common features of tumors is hypoxia, which drives the process of tumor angiogenesis by regulating the tumor microenvironment, thus adversely affecting the prognosis of patients. In addition, to overcome unsuitable environments for growth, such as hypoxia, nutrient deficiency, hyperacidity, and immunosuppression, the tumor microenvironment (TME) coordinates angiogenesis in several ways to restore the supply of oxygen and nutrients and to remove metabolic wastes. A growing body of research suggests that tumor angiogenesis and hypoxia interact through a complex interplay of crosstalk, which is inextricably linked to the TME. Here, we review the TME's positive contribution to angiogenesis from an angiogenesis-centric perspective while considering the objective impact of hypoxic phenotypes and the status and limitations of current angiogenic therapies.

Application of immune checkpoint inhibitors for resectable gastric/gastroesophageal cancer

Gastric/gastroesophageal junction (G/GEJ) cancer represents a significant global health challenge. Radical surgery remains the cornerstone of treatment for resectable G/GEJ cancer. Supported by robust evidence from multiple clinical studies, therapeutic approaches, including adjuvant chemotherapy or chemoradiation, and perioperative chemotherapy, are generally recommended to reduce the risk of recurrence and enhance long-term survival outcomes post-surgery. In recent years, immune checkpoint inhibitors (ICIs) have altered the landscape of systemic treatment for advanced or metastatic G/GEJ cancer, becoming the standard first-line therapy for specific patients. Consequently, exploring the efficacy of ICIs in the adjuvant or neoadjuvant setting for resectable G/GEJ cancer is worthwhile. This review summarizes the current advances in the application of ICIs for resectable G/GEJ cancer.

Novel Molecular Targets in Endometrial Cancer: Mechanisms and Perspectives for Therapy

Endometrial cancer (EC) has a high epidemiological impact with incidence and mortality rising worldwide. In recent years, the integration of the pathologic and molecular classification has provided relevant information to understand the heterogeneity in the biology of EC, which led to the evolution in the management of patients. Currently, therapeutic breakthroughs have been made in advanced EC to improve oncologic outcomes, with efforts to include patient reported outcomes. Precision and personalized medicine are under way in EC exploring different combination approaches to target cross-talk pathways, cancer cell microenvironment, and metabolic vulnerabilities and improve drug delivery. Yet, collaborative efforts are needed to face the challenges in practice by refining patient selection, ideal biomarker identification, and de-escalation of therapies according to emerging molecular and genomic features of EC.

Targeting HER2-positive breast cancer cells by a combination of dasatinib and BMS-202: Insight into the molecular pathways

BACKGROUND

Recent investigations have reported the benefits of using a tyrosine kinase inhibitor, dasatinib (DA), as well as programmed death-ligand 1 (PD-L1) inhibitors in the management of several solid tumors, including breast cancer. Nevertheless, the outcome of the combination of these inhibitors on HER2-positive breast cancer is not explored yet.

METHODS

Herein, we investigated the impact of DA and PD-L1 inhibitor (BMS-202) combination on HER2-positive breast cancer cell lines, SKBR3 and ZR75.

RESULTS

Our data reveal that the combination significantly inhibits cell viability of both cancer cell lines as compared to monotreatment. Moreover, the combination inhibits epithelial-mesenchymal transition (EMT) progression and reduces cancer cell invasion by restoring E-cadherin and β-catenin expressions and loss of vimentin, major biomarkers of EMT. Additionally, the combination reduces the colony formation of both cell lines in comparison with their matched control. Also, the combination considerably inhibits the angiogenesis of the chorioallantoic membrane model compared with monotreatment. Molecular pathway analysis of treated cells shows that this combination blocks HER2, AKT, β-catenin, and JNK1/2/3 activities.

CONCLUSION

Our findings implicate that a combination of DA and BMS-202 could have a significant impact on the management of HER2-positive breast cancer.

Immune checkpoint inhibitor therapy in neoadjuvant and adjuvant treatment for cancer: A paradigm shift in the treatment of resectable gastrointestinal cancer 3)A paradigm shift in the treatment of colorectal cancer

Immune checkpoint inhibitors, such as anti-programmed cell death-1, programmed cell death ligand-1, and cytotoxic T-lymphocyte antigen-4 monoclonal antibodies, have been notably effective in various types of cancers. Mismatch repair deficiency and microsatellite instability-high tumors have been established as striking biomarkers for response to immune checkpoint inhibitors. These biomarkers show a higher mutational burden, have cancer-associated neoantigens, and dense immune cell infiltration, which generates a robust immune response. For metastatic colorectal cancer, pembrolizumab and nivolumab, with or without ipilimumab, are recommended for chemotherapy-refractory patients, and pembrolizumab is recommended for chemotherapy-naive patients with mismatch repair deficiency and microsatellite instability-high tumors. Conversely, patients with mismatch repair-proficient and microsatellite-stable metastatic colorectal cancer showed no clinical benefit from immune checkpoint inhibitor monotherapy. Currently, combination therapy with anti-programmed cell death-1/programmed cell death ligand-1 and cytotoxic T-lymphocyte antigen-4 monoclonal antibodies or a combination of immune checkpoint inhibitors with molecular targeting agents or radiotherapy have been investigated to modulate immune cells and enhance therapeutic efficacy in mismatch repair-proficient and microsatellite-stable metastatic colorectal cancer. Furthermore, immune checkpoint inhibitors have been developed for neoadjuvant and adjuvant settings. In this review, we summarize the existing clinical data and discuss future perspectives with a focus on immune checkpoint inhibitor-based treatments for colorectal cancer.

Clinical significance of circulating tumor DNA in localized non-small cell lung cancer: a systematic review and meta-analysis

Circulating tumor DNA (ctDNA) detection holds promise for genetic analyses and quantitative assessment of tumor burden. A systematic review and meta-analysis were conducted to investigate the clinical relevance of ctDNA among patients with localized non-small cell lung cancer (NSCLC). PubMed, EMBASE, and the Cochrane Library were searched for eligible studies published from January 2001 to April 2022. After quality assessments and data extraction, diagnostic accuracy variables and prognostic data were calculated and analyzed by Meta-Disc 1.4, Review Manager 5.4.1, and STATA 17.0. Eight prospective studies and one retrospective study including 784 patients with localized NSCLC were used in our meta-analysis. The pooled sensitivity and specificity of ctDNA for minimal residual disease (MRD) detection were 0.58 and 0.93, respectively. The pooled positive and negative likelihood ratios were 7.57 (95% confidence interval (CI) 2.84-20.20) and 0.45 (95% CI 0.37-0.55), respectively. The area under the summary receiver operating characteristic curve was 0.8967, and the diagnostic odds ratio was 32.26 (95% CI 14.63-71.12). In addition, both precurative-treatment and postcurative-treatment ctDNA positivity was associated with worse recurrence-free survival (hazard ratio (HR), 3.82 and 8.32, respectively) and worse overall survival (HR, 3.82 and 4.73, respectively). The findings suggested that ctDNA detection has beneficial utility regarding MRD detection specificity; moreover, positive ctDNA was associated with poor prognosis in patients with localized NSCLC.

The effects of anti-PD-L1 monoclonal antibody on the expression of angiogenesis and invasion-related genes

Background/aim

The role of PD-L1 in regulating the immunosuppressive tumor microenvironment via its binding on PD-1 receptors is extensively studied. The PD-1/PD-L1 axis is a significant way of cancer immune escape, and PD-L1 expression on tumor cells is suggested as a predictive marker for anti-PD-1/PD-L1 monoclonal antibodies (MoAbs). However, the tumor-intrinsic role of PD-L1 is not known well. Therefore, we aimed to investigate the effects of anti-PD-L1 antibodies on the expression of angiogenesis and metastasis-related genes in tumor cells.

Materials and methods

The experiments were done with prostate cancer and melanoma cells with low PD-L1 expression (<5%) and prostate and breast cancer cells with high PD-L1 expression (>50%). The gene and protein expressions of VEGFA, E-cadherin, TGFβ1, EGFR, and bFGF in tumor cells were assayed at the 3 different doses of the anti-PD-L1 antibody.

Results

We found that VEGFA, E-cadherin and TGFβ1 expressions increased in PD-L1 high cells but decreased in PD-L1 low cells after anti-PD-L1 treatment. EGFR expression levels were variable in PD-L1 high cells, while decreased in PD-L1 low cells upon treatment. Also, the anti-PD-L1 antibody was found to increase bFGF expression in the prostate cancer cell line with high PD-L1 expression.

Conclusion

Our results suggest that the binding of PD-L1 on tumor cells by an anti-PD-L1 monoclonal antibody may affect tumor-intrinsic mechanisms. The activation of angiogenesis and metastasis-related pathways by anti-PD-L1 treatment in PD-L1 high tumors might be a tumor-promoting mechanism. The decrease of VEGFA, TGFβ1 and EGFR upon anti-PD-L1 treatment in PD-L1 low tumor cells provides a rationale for the use of those antibodies in PD-L1 low tumors.

Angiogenic signaling pathways and anti-angiogenic therapy for cancer

Angiogenesis, the formation of new blood vessels, is a complex and dynamic process regulated by various pro- and anti-angiogenic molecules, which plays a crucial role in tumor growth, invasion, and metastasis. With the advances in molecular and cellular biology, various biomolecules such as growth factors, chemokines, and adhesion factors involved in tumor angiogenesis has gradually been elucidated. Targeted therapeutic research based on these molecules has driven anti-angiogenic treatment to become a promising strategy in anti-tumor therapy. The most widely used anti-angiogenic agents include monoclonal antibodies and tyrosine kinase inhibitors (TKIs) targeting vascular endothelial growth factor (VEGF) pathway. However, the clinical benefit of this modality has still been limited due to several defects such as adverse events, acquired drug resistance, tumor recurrence, and lack of validated biomarkers, which impel further research on mechanisms of tumor angiogenesis, the development of multiple drugs and the combination therapy to figure out how to improve the therapeutic efficacy. Here, we broadly summarize various signaling pathways in tumor angiogenesis and discuss the development and current challenges of anti-angiogenic therapy. We also propose several new promising approaches to improve anti-angiogenic efficacy and provide a perspective for the development and research of anti-angiogenic therapy.

Endothelial Rap1B mediates T-cell exclusion to promote tumor growth: a novel mechanism underlying vascular immunosuppression

Overcoming vascular immunosuppression: lack of endothelial cell (EC) responsiveness to inflammatory stimuli in the proangiogenic environment of tumors, is essential for successful cancer immunotherapy. The mechanisms through which Vascular Endothelial Growth Factor A(VEGF-A) modulates tumor EC response to exclude T-cells are not well understood. Here, we demonstrate that EC-specific deletion of small GTPase Rap1B, previously implicated in normal angiogenesis, restricts tumor growth in endothelial-specific Rap1B-knockout (Rap1BiΔEC) mice. EC-specific Rap1B deletion inhibits angiogenesis, but also leads to an altered tumor microenvironment with increased recruitment of leukocytes and increased activity of tumor CD8+ T-cells. Depletion of CD8+ T-cells restored tumor growth in Rap1BiΔEC mice. Mechanistically, global transcriptome and functional analyses indicated upregulation of signaling by a tumor cytokine, TNF-α, and increased NF-κB transcription in Rap1B-deficient ECs. Rap1B-deficiency led to elevated proinflammatory chemokine and Cell Adhesion Molecules (CAMs) expression in TNF-α stimulated ECs. Importantly, CAM expression was elevated in tumor ECs from Rap1BiΔEC mice. Significantly, Rap1B deletion prevented VEGF-A-induced immunosuppressive downregulation of CAM expression, demonstrating that Rap1B is essential for VEGF-A-suppressive signaling. Thus, our studies identify a novel endothelial-endogenous mechanism underlying VEGF-A-dependent desensitization of EC to proinflammatory stimuli. Significantly, they identify EC Rap1B as a potential novel vascular target in cancer immunotherapy.

Targeting programmed cell death protein 1 (PD-1) for treatment of non-small-cell lung carcinoma (NSCLC); the recent advances

The immune system uses various immune checkpoint axes to adjust responses, support homeostasis, and deter self-reactivity and autoimmunity. Nevertheless, non-small-cell lung carcinoma (NSCLC) can use protective mechanisms to facilitate immune evasion, which leads to potentiated cancer survival and proliferation. In this light, many blocking anti-bodies have been developed to negatively regulate checkpoint molecules, in particular, programmed cell death protein 1 (PD-1) / PD-ligand 1 (L1), and bypass these immune suppressive mechanisms. Meanwhile, anti-PD-1 anti-bodies such as nivolumab, pembrolizumab, cemiplimab, and sintilimab have shown excellent competence in successfully inspiring immune responses versus NSCLC. Accordingly, the United States Food and Drug Administration (FDA) has recently approved nivolumab (alone or in combination with ipilimumab) and pembrolizumab (alone or in combination with chemotherapy) as first-line treatment for advanced NSCLC patients. However, PD-1 blockade monotherapy remains inefficient in more than 60% of NSCLC patients, and many patients don't respond or acquire resistance to this modality. Also, toxicities related to anti-PD-1 anti-body have been progressively identified in clinical trials and oncology practice. Herein, we will outline the clinical benefits of PD-1 blockade therapy alone or in combination with other treatments (e.g., chemotherapy, radiotherapy, anti-angiogenic therapy) in NSCLC patients. Moreover, we will take a glimpse into the recently identified predictive biomarkers to determine patients most likely to suffer serious adverse events to decrease untoward toxicity risk and diminish treatment costs.

Lenvatinib or anti-VEGF in combination with anti-PD-1 differentially augments antitumor activity in melanoma

Targeting tumor-associated blood vessels to increase immune infiltration may enhance treatment effectiveness, yet limited data exist regarding anti-angiogenesis effects on the tumor microenvironment (TME). We hypothesized that dual targeting of angiogenesis with immune checkpoints would improve both intracranial and extracranial disease. We used subcutaneous and left ventricle melanoma models to evaluate anti-PD-1/anti-VEGF and anti-PD-1/lenvatinib (pan-VEGFR inhibitor) combinations. Cytokine/chemokine profiling and flow cytometry were performed to assess signaling and immune-infiltrating populations. An in vitro blood-brain barrier (BBB) model was utilized to study intracranial treatment effects on endothelial integrity and leukocyte transmigration. Anti-PD-1 with either anti-VEGF or lenvatinib improved survival and decreased tumor growth in systemic melanoma murine models; treatment increased Th1 cytokine/chemokine signaling. Lenvatinib decreased tumor-associated macrophages but increased plasmacytoid DCs early in treatment; this effect was not evident with anti-VEGF. Both lenvatinib and anti-VEGF resulted in decreased intratumoral blood vessels. Although anti-VEGF promoted endothelial stabilization in an in vitro BBB model, while lenvatinib did not, both regimens enabled leukocyte transmigration. The combined targeting of PD-1 and VEGF or its receptors promotes enhanced melanoma antitumor activity, yet their effects on the TME are quite different. These studies provide insights into dual anti-PD-1 and anti-angiogenesis combinations.

T cell-dependent bispecific antibodies alter organ-specific endothelial cell-T cell interaction

Preclinical and clinical studies demonstrate that T cell-dependent bispecific antibodies (TDBs) induce systemic changes in addition to tumor killing, leading to adverse events. Here, we report an in-depth characterization of acute responses to TDBs in tumor-bearing mice. Contrary to modest changes in tumors, rapid and substantial lymphocyte accumulation and endothelial cell (EC) activation occur around large blood vessels in normal organs including the liver. We hypothesize that organ-specific ECs may account for the differential responses in normal tissues and tumors, and we identify a list of genes selectively upregulated by TDB in large liver vessels. Using one of the genes as an example, we demonstrate that CD9 facilitates ICAM-1 to support T cell-EC interaction in response to soluble factors released from a TDB-mediated cytotoxic reaction. Our results suggest that multiple factors may cooperatively promote T cell infiltration into normal organs as a secondary response to TDB-mediated tumor killing. These data shed light on how different vascular beds respond to cancer immunotherapy and may help improve their safety and efficacy.

Anti-PD-1 plus anti-angiogenesis combined with chemotherapy in patients with HER2-negative advanced or metastatic gastric cancer: a multi-institutional retrospective study

Background

Immunotherapy plus chemotherapy have been confirmed to be effective in treating advanced or metastatic gastric cancer (GC). Anti- programmed death-1 (PD-1) plus antiangiogenic agents have shown promising activity and tolerant toxicity in subsequent therapy of late-stage gastric cancer. The aim of this study was to assess the efficacy and safety of anti-PD-1 plus anti-angiogenic agents and chemotherapy in advanced or metastatic GC and to explore the potential biomarkers associated with response.

Methods

We retrospectively reviewed thirty human epidermal growth factor receptor 2 (HER2)-negative advanced or metastatic GC patients who received PD-1 plus anti-angiogenic drugs and chemotherapy. Conversion therapy was defined when the patients could undergo resection post combination therapy. Clinical data were retrieved from medical records. We conducted exploratory biomarker analysis of baseline gene mutations and tumor mutation burden (TMB) using the next-generation sequencing (NGS), PD-L1 by immunohistochemistry (IHC), and the tumor immune microenvironment (TIME) by multiplex immunofluorescence.

Results

A total of 30 patients received anti-PD-1plus anti-angiogenic drugs and chemotherapy during the study period. The objective response rate (ORR) was 76.7% [95% confidence interval (CI): 57.7-90.1%] and disease control rate (DCR) was 86.7% (95% CI: 69.3-96.2%). A total of 11 patients (36.7%) achieved conversion therapy and underwent surgery. The R0 resection rate was 90.9%. Of the 11 patients, 9 (81.8%) responded to the treatment, 1 with a pathological complete response (pCR) and 8 with a major pathological response (MPR). No adverse events of grade 3 or higher occurred. Neither PD-L1 expression nor TMB was significantly correlated with treatment response. Analysis of TIME revealed that the fraction of CD8⁺ T cell in the invasive margin was higher in responders than non-responders before treatment. TAM2 in the tumor center and CD8⁺ T cell in the invasive margin was significantly increased after combination therapy, which suggested that combination therapy promoted infiltration of CD8⁺ T cells, thereby exerting an antitumor effect.

Conclusions

Immunotherapy plus anti-angiogenic drugs and chemotherapy is a promising treatment strategy for advanced or metastatic GC patients. Tumor infiltration CD8⁺ T cells may serve as potential predictive biomarker.

The Role of Pericytes in Regulation of Innate and Adaptive Immunity

Pericytes are perivascular multipotent cells wrapping microvascular capillaries, where they support vasculature functioning, participate in tissue regeneration, and regulate blood flow. However, recent evidence suggests that in addition to traditionally credited structural function, pericytes also manifest immune properties. In this review, we summarise recent data regarding pericytes' response to different pro-inflammatory stimuli and their involvement in innate immune responses through expression of pattern-recognition receptors. Moreover, pericytes express various adhesion molecules, thus regulating trafficking of immune cells across vessel walls. Additionally, the role of pericytes in modulation of adaptive immunity is discussed. Finally, recent reports have suggested that the interaction with cancer cells evokes immunosuppression function in pericytes, thus facilitating immune evasion and facilitating cancer proliferation and metastasis. However, such complex and multi-faceted cross-talks of pericytes with immune cells also suggest a number of potential pericyte-based therapeutic methods and techniques for cancer immunotherapy and treatment of autoimmune and auto-inflammatory disorders.

Case Report: Chemotherapy-free treatment with camrelizumab and anlotinib for elderly patients with KRAS and TP53 mutated advanced lung cancer

Background: Lung cancer is a major public health issue and an enormous burden on society in China. Most lung cancers occur in elderly patients with non-small cell lung cancer (NSCLC), and many factors limit their treatment options. Chemotherapy-free therapy can avoid psychological fear, treatment pain, and adverse reactions caused by chemotherapy. Patients with non-small cell lung cancer with tumour protein p53 (TP53) gene mutations or Kirsten rat sarcoma viral oncogene homologue (KRAS) gene mutations tend to be more sensitive to anlotinib or programmed cell death protein 1 (PD-1) drugs. However, Kirsten rat sarcoma viral oncogene homologue is a proto-oncogene downstream of the epidermal growth factor receptor (EGFR) gene; therefore, if the Kirsten rat sarcoma viral oncogene homologue gene has an activating mutation, EGFR-targeted drug resistance may occur. Further studies are needed to explore whether patients with dual Kirsten rat sarcoma viral oncogene homologue and tumour protein p53 mutations can be treated with targeted immunotherapy without chemotherapy. Case presentation: A 74-year-old man was referred to the Lanzhou University Second Hospital due to chest tightness, shortness of breath, and weight loss for 2 months and was diagnosed with moderately to poorly differentiated adenocarcinoma. Laboratory examinations showed increased alpha-fetoprotein (AFP), carcinoembryonic antigen (CEA), cancer antigen (CA)-125, and CA199 levels, and gene sequencing indicated mutations in Kirsten rat sarcoma viral oncogene homologue and tumour protein p53. Immunohistochemical analysis showed positive PD-L1 and PD-1 expression. Peripheral blood immune checkpoint test using flow cytometry indicated that the PD-1 + CD8 levels were positive. After multi-disciplinary treatment, therapy with a combination of anlotinib and camrelizumab was initiated. Camrelizumab 200 mg was administered intravenously once every 3 weeks. Anlotinib 12 mg was administered orally daily before breakfast for 2 weeks with a week of rest in every cycle of 21 days. A reduction in alpha-fetoprotein, carcinoembryonic antigen, CA125, CA199, and CA724 levels was observed up to the first cycle, which decreased within the normal limits up to the second cycle and continued until the eighteenth cycle. The patient's chest tightness, shortness of breath, weight loss, and other symptoms significantly improved following treatment. Computed tomography imaging showed that the neoplastic lesion was dramatically reduced. The patient is currently being followed-up for more than 2 years to evaluate the duration of the response. Conclusion: Chemotherapy-free immunotherapy combined with targeted therapy is an effective treatment for advanced non-small cell lung cancer in elderly patients with Kirsten rat sarcoma viral oncogene homologue and tumour protein p53 mutations. Such therapies should be supported with further clinical studies with larger sample sizes.

Challenges in neoantigen-directed therapeutics

A fundamental prerequisite for the efficacy of cancer immunotherapy is the presence of functional, antigen-specific T cells within the tumor. Neoantigen-directed therapy is a promising strategy that aims at targeting the host's immune response against tumor-specific antigens, thereby eradicating cancer cells. Initial forays have been made in clinical environments utilizing vaccines and adoptive cell therapy; however, many challenges lie ahead. We provide an in-depth overview of the current state of the field with an emphasis on in silico neoantigen discovery and the clinical aspects that need to be addressed to unlock the full potential of this therapy.

A novel anti-PD-L1/IL-15 immunocytokine overcomes resistance to PD-L1 blockade and elicits potent antitumor immunity

Despite the demonstrated immense potential of immune checkpoint inhibitors in various types of cancers, only a minority of patients respond to these therapies. Immunocytokines designed to deliver an immune-activating cytokine directly to the immunosuppressive tumor microenvironment (TME) and block the immune checkpoint simultaneously may provide a strategic advantage over the combination of two single agents. To increase the response rate to checkpoint blockade, in this study, we developed a novel immunocytokine (LH01) composed of the antibody against programmed death-ligand 1 (PD-L1) fused to interleukin (IL)-15 receptor alpha-sushi domain/IL-15 complex. We demonstrate that LH01 efficiently binds mouse or human PD-L1 and maintains IL-15 stimulatory activity. In syngeneic mouse models, LH01 showed improved antitumor efficacy and safety versus anti-PD-L1 plus LH02 (Fc-sushi-IL15) combination and overcame resistance to anti-PD-L1 treatment. Mechanistically, the dual anti-immunosuppressive function of LH01 activated both the innate and adaptive immune responses and induced a favorable and immunostimulatory TME. Furthermore, combination therapy with LH01 and bevacizumab exerts synergistic antitumor effects in an HT29 colorectal xenograft model. Collectively, our results provide supporting evidence that fusion of anti-PD-L1 and IL-15 might be a potent strategy to treat patients with cold tumors or resistance to checkpoint blockade.

Neoadjuvant therapy with immune checkpoint blockade, antiangiogenesis, and chemotherapy for locally advanced gastric cancer

Despite neoadjuvant/conversion chemotherapy, the prognosis of cT4a/bN+ gastric cancer is poor. Immune checkpoint inhibitors (ICIs) and antiangiogenic agents have shown activity in late-stage gastric cancer, but their efficacy in the neoadjuvant/conversion setting is unclear. In this single-armed, phase II, exploratory trial (NCT03878472), we evaluate the efficacy of a combination of ICI (camrelizumab), antiangiogenesis (apatinib), and chemotherapy (S-1 ± oxaliplatin) for neoadjuvant/conversion treatment of cT4a/bN+ gastric cancer. The primary endpoints are pathological responses and their potential biomarkers. Secondary endpoints include safety, objective response, progression-free survival, and overall survival. Complete and major pathological response rates are 15.8% and 26.3%. Pathological responses correlate significantly with microsatellite instability status, PD-L1 expression, and tumor mutational burden. In addition, multi-omics examination reveals several putative biomarkers for pathological responses, including RREB1 and SSPO mutation, immune-related signatures, and a peripheral T cell expansion score. Multi-omics also demonstrates dynamic changes in dominant tumor subclones, immune microenvironments, and T cell receptor repertoires during neoadjuvant immunotherapy. The toxicity and post-surgery complications are limited. These data support further validation of ICI- and antiangiogenesis-based neoadjuvant/conversion therapy in large randomized trials and provide candidate biomarkers.

Pivotal role of PD-1/PD-L1 immune checkpoints in immune escape and cancer progression: Their interplay with platelets and FOXP3+Tregs related molecules, clinical implications and combinational potential with phytochemicals

Immune checkpoint proteins including programmed cell death protein 1 (PD-1), its ligand PD-L1 and cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) are involved in proliferation, angiogenesis, metastasis, chemoresistance via immune escape and immune tolerance by disturbing cytotoxic T cell activation. Though many clinical trials have been completed in several cancers by using immune checkpoint inhibitors alone or in combination with other agents to date, recently multi-target therapy is considered more attractive than monotherapy, since immune checkpoint proteins work with other components such as surrounding blood vessels, dendritic cells, fibroblasts, macrophages, platelets and extracellular matrix within tumor microenvironment. Thus, in the current review, we look back on research history of immune checkpoint proteins and discuss their associations with platelets or tumor cell induced platelet aggregation (TCIPA) and FOXP3+ regulatory T cells (Tregs) related molecules involved in immune evasion and tumor progression, clinical implications of completed trial results and signaling networks by phytochemicals for combination therapy with immune checkpoint inhibitors and suggest future research perspectives.

Disrupting cancer angiogenesis and immune checkpoint networks for improved tumor immunity

Immune checkpoint inhibitors (ICIs) have advanced the field of cancer immunotherapy in patients by sustaining effector immune cell activity within the tumor microenvironment. However, the approach in general is still faced with issues related to ICI response duration/resistance, treatment eligibility, and safety, which indicates a need for further refinements. As immune checkpoint upregulation is inextricably linked to cancer-induced angiogenesis, newer clinical efforts have demonstrated the feasibility of disrupting both tumor-promoting networks to mediate enhanced immune-driven protection. This review focuses on such key evidence stipulating the necessity of co-applying ICI and anti-angiogenic strategies in cancer patients, with particular interest in highlighting newer engineered antibody approaches that may provide theoretically superior multi-pronged and safe therapeutic combinations.

Biomarker-Targeted Therapies in Non-Small Cell Lung Cancer: Current Status and Perspectives

Non-small-cell lung cancer (NSCLC) is one of the most common malignancies and the leading causes of cancer-related death worldwide. Despite many therapeutic advances in the past decade, NSCLC remains an incurable disease for the majority of patients. Molecular targeted therapies and immunotherapies have significantly improved the prognosis of NSCLC. However, the vast majority of advanced NSCLC develop resistance to current therapies and eventually progress. In this review, we discuss current and potential therapies for NSCLC, focusing on targeted therapies and immunotherapies. We highlight the future role of metabolic therapies and combination therapies in NSCLC.

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.

Tumor vessel normalization and immunotherapy in gastric cancer

Gastric cancer (GC) is a common malignant tumor, and patients with GC have a low survival rate due to limited effective treatment methods. Angiogenesis and immune evasion are two key processes in GC progression, and they act synergistically to promote tumor progression. Tumor vascular normalization has been shown to improve the efficacy of cancer immunotherapy, which in turn may be improved through enhanced immune stimulation. Therefore, it may be interesting to identify synergies between immunomodulatory agents and anti-angiogenic therapies in GC. This strategy aims to normalize the tumor microenvironment through the action of the anti-vascular endothelial growth factor while stimulating the immune response through immunotherapy and prolonging the survival of GC patients.

Usefulness of Hounsfield Units and the Serum Neutrophil-to-Lymphocyte Ratio as Prognostic Factors in Patients with Breast Cancer

Breast cancer is a leading cause of death worldwide. Tumor vascularity and immune disturbances are hallmarks of cancer. This study aimed to investigate the reciprocal effect of tumor vascularity, assessed by the tumor-to-aorta ratio (TAR) of Hounsfield units (HU) on computed tomography (CT), and host immunity, represented by the serum neutrophil-to-lymphocyte ratio (NLR) from peripheral, complete blood cell counts and its impact on patient survival. Female patients with breast cancer who received primary treatment between 2003 and 2018 at Wonju Severance Hospital, Korea, were included. The final cohort included 740 patients with a mean age of 54.3 ± 11.3 (22−89) years. The TAR was 0.347 ± 0.108 (range, 0.062−1.114) and the NLR was 2.29 ± 1.53 (0.61−10.47). The cut-off value for the TAR and NLR were 0.27 and 1.61, respectively. The patients with a TAR > 0.27 showed a poor recurrence free-interval (RFI) only when their NLR was larger than 1.61, and vice versa. The patients showed worse RFI when they had both high TAR and NLR. Our results suggest a dynamic reciprocal communication between tumor vascularity and systemic immunity.

The Evasion Mechanisms of Cancer Immunity and Drug Intervention in the Tumor Microenvironment

Recently, in the field of cancer treatment, the paradigm has changed to immunotherapy that activates the immune system to induce cancer attacks. Among them, immune checkpoint inhibitors (ICI) are attracting attention as excellent and continuous clinical results. However, it shows not only limitations such as efficacy only in some patients or some indications, but also side-effects and resistance occur. Therefore, it is necessary to understand the factors of the tumor microenvironment (TME) that affect the efficacy of immunotherapy, that is, the mechanism by which cancer grows while evading or suppressing attacks from the immune system within the TME. Tumors can evade attacks from the immune system through various mechanisms such as restricting antigen recognition, inhibiting the immune system, and inducing T cell exhaustion. In addition, tumors inhibit or evade the immune system by accumulating specific metabolites and signal factors within the TME or limiting the nutrients available to immune cells. In order to overcome the limitations of immunotherapy and develop effective cancer treatments and therapeutic strategies, an approach is needed to understand the functions of cancer and immune cells in an integrated manner based on the TME. In this review, we will examine the effects of the TME on cancer cells and immune cells, especially how cancer cells evade the immune system, and examine anti-cancer strategies based on TME.

A phase II, open-label, single-arm trial of carboplatin plus etoposide with bevacizumab and atezolizumab in patients with extended-stage small-cell lung cancer (CeLEBrATE study): background, design and rationale

Based on improved survival from the addition of PD-L1 inhibitors in phase III trials, the combination of immunotherapy and platinum-doublet chemotherapy has become the new standard treatment for extended-stage small-cell lung cancer (ES-SCLC). Furthermore, the antiangiogenetic agent bevacizumab showed a longer progression-free survival by targeting VEGF that has pleiotropic effects, including immunosuppressive ones. We, therefore, hypothesized that targeting angiogenesis would improve the efficacy of chemoimmunotherapy. The CeLEBrATE trial is an open-label, multicenter, phase II study designed to assess the efficacy and safety of the combination of carboplatin and etoposide plus bevacizumab and atezolizumab in treatment-naive patients with ES-SCLC. The primary end point is overall survival rate at 1 year, while secondary end points include overall response rate, progression-free survival and toxicity.

Targeting Angiogenesis in Breast Cancer: Current Evidence and Future Perspectives of Novel Anti-Angiogenic Approaches

Angiogenesis is a vital process for the growth and dissemination of solid cancers. Numerous molecular pathways are known to drive angiogenic switch in cancer cells promoting the growth of new blood vessels and increased incidence of distant metastasis. Several angiogenesis inhibitors are clinically available for the treatment of different types of advanced solid cancers. These inhibitors mostly belong to monoclonal antibodies or small-molecule tyrosine kinase inhibitors targeting the classical vascular endothelial growth factor (VEGF) and its receptors. Nevertheless, breast cancer is one example of solid tumors that had constantly failed to respond to angiogenesis inhibitors in terms of improved survival outcomes of patients. Accordingly, it is of paramount importance to assess the molecular mechanisms driving angiogenic signaling in breast cancer to explore suitable drug targets that can be further investigated in preclinical and clinical settings. This review summarizes the current evidence for the effect of clinically available anti-angiogenic drugs in breast cancer treatment. Further, major mechanisms associated with intrinsic or acquired resistance to anti-VEGF therapy are discussed. The review also describes evidence from preclinical and clinical studies on targeting novel non-VEGF angiogenic pathways in breast cancer and several approaches to the normalization of tumor vasculature by targeting pericytes, utilization of microRNAs and extracellular tumor-associate vesicles, using immunotherapeutic drugs, and nanotechnology.

Immune Checkpoint Inhibitors in Non-Small Cell Lung Cancer: Progress, Challenges, and Prospects

Non-small cell lung cancer is one of the most common types of malignances worldwide and the main cause of cancer-related deaths. Current treatment for NSCLC is based on surgical resection, chemotherapy, radiotherapy, and targeted therapy, with poor therapeutic effectiveness. In recent years, immune checkpoint inhibitors have applied in NSCLC treatment. A large number of experimental studies have shown that immune checkpoint inhibitors are safer and more effective than traditional therapeutic modalities and have allowed for the development of better guidance in the clinical treatment of advanced NSCLC patients. In this review, we describe clinical trials using ICI immunotherapies for NSCLC treatment, the available data on clinical efficacy, and the emerging evidence regarding biomarkers.

Resistance to Immunotherapy: Mechanisms and Means for Overcoming

Immune checkpoint blockade transformed cancer therapy during the last decade. However, durable responses remain uncommon, early and late relapses occur over the course of treatment, and many patients with PD-L1-expressing tumors do not respond to PD-(L)1 blockade. In addition, while some malignancies exhibit inherent resistance to treatment, others develop adaptations that allow them to evade antitumor immunity after a period of response. It is crucial to understand the pathophysiology of the tumor-immune system interplay and the mechanisms of immune escape in order to circumvent primary and acquired resistance. Here we provide an outline of the most well-defined mechanisms of resistance and shed light on ongoing efforts to reinvigorate immunoreactivity.

Anti-Angiogenic Agent Combined with Anti-PD-1 Immunotherapy Showed Activity in Patients With Classical Hodgkin Lymphoma Who Have Failed Immunotherapy: A Retrospective Case Report Study

Background

PD-1/PD-L1 inhibitor immunotherapy has showed impressive activity in various cancers, especially relapsed/refractory (r/r) classical Hodgkin lymphoma (cHL). However, acquired resistance is inevitable for most patients. Sometimes severe side effects also lead to treatment termination. When immunotherapy failed, alternative treatment options are limited. In the past few years, we have used the anti-angiogenic agent apatinib and PD-1 inhibitor camrelizumab to treat cHL patients who failed prior immunotherapy. In this study, we analyzed the data of these patients.

Patients and Methods

Patients with r/r cHL who had failed immunotherapy and subsequently received apatinib-camrelizumab (AC) combination therapy were included in this study. Patient data were collected from medical records and follow-up system. The efficacy and safety of AC therapy were analyzed.

Results

Seven patients who failed immunotherapy were identified in our database, of which five patients acquired immunotherapy resistance and two patients experienced severe side effects. They received a combination of camrelizumab (200 mg every four weeks) and apatinib (425 mg or 250 mg per day). As of the cut-off date, these patients had received a median of 4 cycles (range, 2 - 31) of treatment. Two (2/7) patients achieved complete response, four (4/7) partial response, and one (1/7) stable disease. The median progression-free survival was 10.0 months (range, 2.0 – 27.8). Low-dose apatinib (250 mg) plus camrelizumab was well tolerated and had no unexpected side effects. Besides, no reactive cutaneous capillary endothelial proliferation was observed in AC-treated patients.

Conclusions

Low dose apatinib plus camrelizumab might be a promising treatment option for r/r cHL patients who have failed immunotherapy. This combination treatment is worthy of further investigation in more patients including solid cancer patients who have failed immunotherapy.

Programmed death (PD)-1/PD-ligand 1 blockade mediates antiangiogenic effects by tumor-derived CXCL10/11 as a potential predictive biomarker

Immune checkpoint inhibitor (ICI) programmed death (PD)-1/PD-ligand 1 (PD-L1) blockade has been approved for various cancers. However, the underlying antitumor mechanisms mediated by ICIs and the predictive biomarkers remain unclear. We report the effects of anti-PD-L1/PD-1 Ab in tumor angiogenesis. In syngeneic mouse models, anti-PD-L1 Ab inhibited tumor angiogenesis and induces net-like hypoxia only in ICI-sensitive cell lines. In tumor tissue and serum of ICI-sensitive cell line-bearing mice, interferon-γ (IFN-γ) inducible angiostatic chemokines CXCL10/11 were upregulated by PD-L1 blockade. In vitro, CXCL10/11 gene upregulation by IFN-γ stimulation in tumor cell lines correlated with the sensitivity of PD-L1 blockade. The CXCL10/11 receptor CXCR3-neutralizing Ab or CXCL11 silencing in tumor cells inhibited the antiangiogenic effect of PD-L1 blockade in vivo. In pretreatment serum of lung carcinoma patients receiving anti-PD-1 Ab, the concentration of CXCL10/11 significantly correlated with the clinical outcome. Our results indicate the antiangiogenic function of PD-1/PD-L1 blockade and identify tumor-derived CXCL10/11 as a potential circulating biomarker of therapeutic sensitivity.

Anlotinib combined with anti-PD-1 antibody, camrelizumab for advanced NSCLCs after multiple lines treatment: An open-label, dose escalation and expansion study

OBJECTIVES

Combined therapy should be invested for those patients who are refractory to first-line therapy. Anti-angiogenic agents could enhance tumor immunity response. We designed a phase IB clinical trial and analyzed the effectiveness and safety of anlotinib combined with PD-1inhibitors Camrelizumab for multi-line pretreated and failed advanced NSCLC to explore the synergistic effect of anti-angiogenic agents and immunotherapy.

METHODS

All enrolled patients should receive camrelizumab 200 mg every 3 weeks. Eligible patients were randomized successively to three dose cohorts of Anlotinib in a dose escalation clinical setting. Once maximal tolerable dose was established, the primary end point of this study was progression-free survival, overall survival and safety. Risk factor was an exploratory end point.

RESULTS

The identified expansion dose for anlotinib was 12 mg. The median PFS of ITT patients was 8.2 months (95% CI, 4.3-12.1 months). And the mOS was 12.7 months (95% CI, 10.2-15.1 months). There was significant difference of mPFS between the 8 mg cohort and the 12 mg cohort (5.6 m vs.11.0 m, p = 0.04). Patients with brain metastasis had a significantly higher risk of death (HR 5.90; 95% CI 2.01-17.30; P = 0.001). Patients whose ECOG was 0 and 1 had a significantly lower risk of death (HR 0.36; 95% CI 0.14-0.91; P = 0.031).

CONCLUSIONS

Anlotinib plus camrelizumab had shown promising efficacy and manageable toxicity as a second-line or later-line treatment for NSCLCs, especially in the 12 mg cohorts. Large-scale phase III clinical trials are needed to further explore the rational combination models and biomarkers.

Autophagy Inhibition by Targeting PIKfyve Potentiates Response to Immune Checkpoint Blockade in Prostate Cancer

Multi-tyrosine kinase inhibitors (MTKIs) have thus far had limited success in the treatment of castration-resistant prostate cancer (CRPC). Here, we report a phase I-cleared orally bioavailable MTKI, ESK981, with a novel autophagy inhibitory property that decreased tumor growth in diverse preclinical models of CRPC. The anti-tumor activity of ESK981 was maximized in immunocompetent tumor environments where it upregulated CXCL10 expression through the interferon gamma pathway and promoted functional T cell infiltration, which resulted in enhanced therapeutic response to immune checkpoint blockade. Mechanistically, we identify the lipid kinase PIKfyve as the direct target of ESK981. PIKfyve-knockdown recapitulated ESK981's anti-tumor activity and enhanced the therapeutic benefit of immune checkpoint blockade. Our study reveals that targeting PIKfyve via ESK981 turns tumors from cold into hot through inhibition of autophagy, which may prime the tumor immune microenvironment in advanced prostate cancer patients and be an effective treatment strategy alone or in combination with immunotherapies.

Anti-angiogenic agents - overcoming tumour endothelial cell anergy and improving immunotherapy outcomes

Immune checkpoint inhibitors have revolutionized medical oncology, although currently only a subset of patients has a response to such treatment. A compelling body of evidence indicates that anti-angiogenic therapy has the capacity to ameliorate antitumour immunity owing to the inhibition of various immunosuppressive features of angiogenesis. Hence, combinations of anti-angiogenic agents and immunotherapy are currently being tested in >90 clinical trials and 5 such combinations have been approved by the FDA in the past few years. In this Perspective, we describe how the angiogenesis-induced endothelial immune cell barrier hampers antitumour immunity and the role of endothelial cell anergy as the vascular counterpart of immune checkpoints. We review the antitumour immunity-promoting effects of anti-angiogenic agents and provide an update on the current clinical successes achieved when these agents are combined with immune checkpoint inhibitors. Finally, we propose that anti-angiogenic agents are immunotherapies - and vice versa - and discuss future research priorities.

Neutrophils in the era of immune checkpoint blockade

The immune checkpoint blockade-based immunotherapies are revolutionizing cancer management. Tumor-associated neutrophils (TANs) were recently highlighted to have a pivotal role in modulating the tumor microenvironment and the antitumor immune response. However, these cells were largely ignored during the development of therapies based on programmed cell death receptor or ligand-1 and cytotoxic T lymphocyte antigen-4 immune checkpoint inhibitors (ICIs). Latest evidences of neutrophil functional diversity in tumor raised many questions and suggest that targeting these cells can offer new treatment opportunities in the context of ICI development. Here, we summarized key information on TAN origin, function, and plasticity that should be considered when developing ICIs and provide a detailed review of the ongoing clinical trials that combine ICIs and a second compound that might affect or be affected by TANs. This review article synthetizes important notions from the literature demonstrating that: (1) Cancer development associates with a profound alteration of neutrophil biogenesis and function that can predict and interfere with the response to ICIs, (2) Neutrophil infiltration in tumor is associated with key features of resistance to ICIs, and (3) TANs play an important role in resistance to antiangiogenic drugs reducing their clinical benefit when used in combination with ICIs. Finally, exploring the clinical/translational aspects of neutrophil impact on the response to ICIs offers the opportunity to propose new translational research avenues to better understand TAN biology and treat patients.

Antiangiogenic therapy reverses the immunosuppressive breast cancer microenvironment

Tumor angiogenesis induces local hypoxia and recruits immunosuppressive cells, whereas hypoxia subsequently promotes tumor angiogenesis. Immunotherapy efficacy depends on the accumulation and activity of tumor-infiltrating immune cells (TIICs). Antangiogenic therapy could improve local perfusion, relieve tumor microenvironment (TME) hypoxia, and reverse the immunosuppressive state. Combining antiangiogenic therapy with immunotherapy might represent a promising option for the treatment of breast cancer. This article discusses the immunosuppressive characteristics of the breast cancer TME and outlines the interaction between the tumor vasculature and the immune system. Combining antiangiogenic therapy with immunotherapy could interrupt abnormal tumor vasculature-immunosuppression crosstalk, increase effector immune cell infiltration, improve immunotherapy effectiveness, and reduce the risk of immune-related adverse events. In addition, we summarize the preclinical research and ongoing clinical research related to the combination of antiangiogenic therapy with immunotherapy, discuss the underlying mechanisms, and provide a view for future developments. The combination of antiangiogenic therapy and immunotherapy could be a potential therapeutic strategy for treatment of breast cancer to promote tumor vasculature normalization and increase the efficiency of immunotherapy.

Targeting Immune Modulators in Glioma While Avoiding Autoimmune Conditions

Communication signals and signaling pathways are often studied in different physiological systems. However, it has become abundantly clear that the immune system is not self-regulated, but functions in close association with the nervous system. The neural-immune interface is complex; its balance determines cancer progression, as well as autoimmune disorders. Immunotherapy remains a promising approach in the context of glioblastoma multiforme (GBM). The primary obstacle to finding effective therapies is the potent immunosuppression induced by GBM. Anti-inflammatory cytokines, induction of regulatory T cells, and the expression of immune checkpoint molecules are the key mediators for immunosuppression in the tumor microenvironment. Immune checkpoint molecules are ligand-receptor pairs that exert inhibitory or stimulatory effects on immune responses. In the past decade, they have been extensively studied in preclinical and clinical trials in diseases such as cancer or autoimmune diseases in which the immune system has failed to maintain homeostasis. In this review, we will discuss promising immune-modulatory targets that are in the focus of current clinical research in glioblastoma, but are also in the precarious position of potentially becoming starting points for the development of autoimmune diseases like multiple sclerosis.

The Efficacy of Anti-PD-L1 Treatment in Melanoma Is Associated with the Expression of the ECM Molecule EMILIN2

The use of immune checkpoint inhibitors has revolutionized the treatment of melanoma patients, leading to remarkable improvements in the cure. However, to ensure a safe and effective treatment, there is the need to develop markers to identify the patients that would most likely respond to the therapies. The microenvironment is gaining attention in this context, since it can regulate both the immunotherapy efficacyand angiogenesis, which is known to be affected by treatment. Here, we investigated the putative role of the ECM molecule EMILIN-2, a tumor suppressive and pro-angiogenic molecule. We verified that the EMILIN2 expression is variable among melanoma patients and is associated with the response to PD-L1 inhibitors. Consistently, in preclinical settings, the absence of EMILIN-2 is associated with higher PD-L1 expression and increased immunotherapy efficacy. We verified that EMILIN-2 modulates PD-L1 expression in melanoma cells through indirect immune-dependent mechanisms. Notably, upon PD-L1 blockage, Emilin2^−/− mice displayed improved intra-tumoral vessel normalization and decreased tumor hypoxia. Finally, we provide evidence indicating that the inclusion of EMILIN2 in a number of gene expression signatures improves their predictive potential, a further indication that the analysis of this molecule may be key for the development of new markers to predict immunotherapy efficacy.

The Anti-VEGF(R) Drug Discovery Legacy: Improving Attrition Rates by Breaking the Vicious Cycle of Angiogenesis in Cancer

Resistance to anti-vascular endothelial growth factor (VEGF) molecules causes lack of response and disease recurrence. Acquired resistance develops as a result of genetic/epigenetic changes conferring to the cancer cells a drug resistant phenotype. In addition to tumor cells, tumor endothelial cells also undergo epigenetic modifications involved in resistance to anti-angiogenic therapies. The association of multiple anti-angiogenic molecules or a combination of anti-angiogenic drugs with other treatment regimens have been indicated as alternative therapeutic strategies to overcome resistance to anti-angiogenic therapies. Alternative mechanisms of tumor vasculature, including intussusceptive microvascular growth (IMG), vasculogenic mimicry, and vascular co-option, are involved in resistance to anti-angiogenic therapies. The crosstalk between angiogenesis and immune cells explains the efficacy of combining anti-angiogenic drugs with immune check-point inhibitors. Collectively, in order to increase clinical benefits and overcome resistance to anti-angiogenesis therapies, pan-omics profiling is key.

Clinical Trials of Immune Checkpoint Inhibitors in Hepatocellular Carcinoma

Introduction: Several immune checkpoint inhibitors (CPIs) are under clinical development in hepatocellular carcinoma (HCC) and the field is advancing rapidly. In this comprehensive review, we discuss published results and report on ongoing clinical trials. Methods: A literature search was carried out using PubMed and EMBASE; data reported at international meetings and clinicaltrials.gov were included as well. The search was updated 5 March 2021. We evaluated studies with monotherapy CPI's, combinations of CPI's and combinations of CPI's with other treatment modalities separately. Only studies with at least 10 included patients were considered. Results: We identified 2649 records published in the English language literature. After review, 29 studies remained, including 12 studies with preliminary data only. The obtained overall response rate of PD-1/PDL-1 monotherapy in phase II studies in the second-line setting was 15-20% with disease control in approximately 60% of patients. The responses were of long duration in a subset of patients. Furthermore, the safety profiles were manageable. However, a phase III study comparing nivolumab with sorafenib in the first-line setting and a phase III study evaluating pembrolizumab versus best supportive care in the second-line setting did not meet their prespecified endpoints. More recently, a phase I/II study of nivolumab and ipilimumab has resulted in a response rate of approximately 30% with a median OS of 22 months in the second-line setting. Multiple trials have been initiated to evaluate CPIs in combination with molecularly targeted drugs, especially anti-angiogenic drugs or local therapy. A phase III study investigating atezolizumab plus bevacizumab versus sorafenib in the first-line setting showed significantly increased survival in the combination arm. Conclusions: The combination of atezolizumab and bevacizumab represents a new standard of care in the first-line setting for fit patients with preserved liver function. CPIs can produce durable tumor remission and induce long-standing anti-tumor immunity in a subgroup of patients with advanced HCC. Although phase III trials of CPI monotherapy have been negative, the combination of PD-1/PD-L1 inhibitors with other anti-angiogenic drugs, CTLA-4 inhibitors or other modalities may result in new treatment options for patients with HCC. Research on predictive biomarkers is crucial for further development of CPIs in HCC.

Reversing T-cell exhaustion in immunotherapy: a review on current approaches and limitations

Introduction:T cell functions are altered during chronic viral infections and tumor development. This is mainly manifested by significant changes in T cells' epigenetic and metabolic landscapes, pushing them into an 'exhausted' state. Reversing this T cell exhaustion has been emerging as a 'game-changing' therapeutic approach against cancer and chronic viral infection.Areas covered:This review discusses the cellular pathways related to T cell exhaustion, and the clinical development and possible cellular targets that can be exploited therapeutically to reverse this exhaustion. We searched various databases (e.g. Google Scholar, PubMed, Elsevier, and other scientific database sites) using the keywords T cell exhaustion, T cell activation, co-inhibitory receptors, and reversing T cell exhaustion.Expert opinion:The discovery of the immune checkpoints pathways represents a significant milestone toward understanding and reversing T cell exhaustion. Antibodies that target these pathways have already demonstrated promising activities in reversing T cell exhaustion. Nevertheless, there are still many associated limitations. In this context, next-generation alternatives are on the horizon. This includes the use of small molecules to block the immune checkpoints' receptors, combining them with other treatments, and identifying novel, safer and more effective immunotherapeutic targets.

Angiogenesis Inhibitors in Small Cell Lung Cancer

Inhibition of angiogenesis has been demonstrated to be an efficacious strategy in treating several tumors. Vascular endothelial growth factor (VEGF) is the most important protein with proangiogenic functions and it is overexpressed in small cell lung cancer (SCLC). Bevacizumab, a monoclonal antibody directed against VEGF, showed a promising activity in combination with etoposide and cisplatin as first-line treatment of patients with extended stage (ES)-SCLC and two randomized studies confirmed that bevacizumab improved PFS, but failed to prolong OS. Instead, disappointing results have been observed with endostar, sunitinib, sorafenib, vandetanib, and thalidomide in combination with chemotherapy in the first-line setting, with sunitinib in the maintenance setting, with sunitinib, cediranib and nintedanib as single agents or ziv-aflibercept in combination with topotecan in second-line setting. Only anlotinib improved OS and PFS as third-line therapy in Chinese patients with SCLC, and it was approved with this indication in China. Future challenges are the evaluation of the role of angiogenesis inhibitors in combination with immune- checkpoint inhibitors and chemotherapy in SCLC patients and the identification of predictive biomarkers of response to both agents.

Efficacy and Safety of Anlotinib in Patients with Advanced Non-Small Cell Lung Cancer: A Real-World Study

Background

Anlotinib is a multi-target tyrosine kinase inhibitor (TKI) independently developed by China, which can inhibit tumor angiogenesis and tumor cell proliferation. The ALTER 0303 study has suggested that anlotinib improved overall survival (OS) and progression-free survival (PFS) in the treatment of advanced non-small cell lung cancer (NSCLC). However, in the real world, the efficacy and safety of anlotinib is not clear. Although relevant retrospective studies have confirmed the efficacy and safety of anlotinib, the sample size is small. And the OS was not observed because of the follow-up time was short. Further studies are still essential to evaluate the efficacy and safety of anlotinib in patients with advanced NSCLC in real-world settings. Related studies have preliminarily shown that anlotinib combined with whole-brain radiotherapy (WBRT) can significantly prolong the survival of patients with brain metastases of NSCLC. This study also discusses the best treatment strategies of patients with brain metastases.

Methods

A retrospective study was conducted on 206 patients with advanced NSCLC who had treated with anlotinib. The primary endpoints were PFS and OS. The secondary endpoints were objective response rate (ORR), disease control rate (DCR) and safety. Kaplan-Meier survival curves were applied to evaluate the efficacy. Univariate analysis was performed by Log rank testing. Cox regression analysis was utilized to evaluate the significance of potential risk factors obtained from the univariate analysis.

Results

The median PFS (mPFS) was 4.0 (95% CI: 3.607-4.393) months, univariate analysis revealed that patients with longer PFS included epidermal growth factor receptor (EGFR) mutation-negative, Eastern Cooperative Oncology Group performance status (ECOG PS) ≤1, no brain metastases, no liver metastases, no adrenal metastases, or ≤2 distant metastases. Cox regression analysis indicated that patients with EGFR-negative and ECOG PS ≤1 had longer PFS. The median OS (mOS) was 8(95% CI: 6.495-9.505) months. EGFR mutation-negative, previous thoracic radiation therapy, no brain metastases, or ≤2 distant metastases were independent positive predictors of OS. The results of Cox regression indicated that the patients without previous thoracic radiation therapy (hazard ratio: 1.855; 95% CI: 1.162-2.960; p=0.010) had shortened OS. The objective response rate was 10.2%, and the disease control rate was 78.2%. The main treatment-related adverse events (AEs) were generally tolerated. All AEs observed during the trial were controlled after dose reduction or symptomatic treatments, and no death was found to be associated with anlotinib.

Conclusion

Anlotinib was well tolerated and effective in patients with advanced NSCLC. Patients with EGFR mutation-negative and ECOG PS ≤1 had longer PFS, and patients without previous thoracic radiation therapy (HR: 1.855, 95% CI 1.162-2.960; P = 0.010) had shorter OS. Further investigations are needed because of small sample.

Direct and Indirect Modulation of T Cells by VEGF-A Counteracted by Anti-Angiogenic Treatment

Vascular endothelial growth factor A is known to play a central role in tumor angiogenesis. Several studies showed that VEGF-A is also an immunosuppressive factor. In tumor-bearing hosts, VEGF-A can modulate immune cells (DC, MDSC, TAM) to induce the accumulation of regulatory T-cells while simultaneously inhibiting T-cell functions. Furthermore, VEGFR-2 expression on activated T-cells and FoxP3^high regulatory T-cells also allow a direct effect of VEGF-A. Anti-angiogenic agents targeting VEGF-A/VEGFR contribute to limit tumor-induced immunosuppression. Based on interesting preclinical studies, many clinical trials have been conducted to investigate the efficacy of anti-VEGF-A/VEGFR treatments combined with immune checkpoint blockade leading to the approvement of these associations in different tumor locations. In this review, we focus on the impact of VEGF-A on immune cells especially regulatory and effector T-cells and different therapeutic strategies to restore an antitumor immunity.

First-line Immunotherapy-based Combinations for Metastatic Renal Cell Carcinoma: A Systematic Review and Network Meta-analysis

CONTEXT

There have been substantial changes in the management of patients with metastatic renal cell carcinoma (mRCC) over the past decade, with upfront immunotherapy-based combinations replacing targeted therapies. A broad range of combinations have been approved, and comparisons of their efficacy and safety are needed to guide the optimal choice of first-line therapy.

OBJECTIVE

To perform indirect comparisons of efficacy and safety of first-line immune checkpoint inhibitor (ICI)-based combination therapies for mRCC.

EVIDENCE ACQUISITION

We searched multiple databases and abstracts of major scientific meetings up to February 2021 to identify phase III randomized controlled trials of patients receiving first-line ICI-based combination therapies for mRCC. Progression-free survival (PFS) and overall survival (OS) were the primary endpoints. The secondary endpoints included complete response rates (CRRs), objective response rates (ORRs), grade ≥3 treatment-related adverse events (TRAEs), and rates of treatment discontinuation due to adverse events (AEs). Subgroup network meta-analyses were performed based on patients' risk group categories and programmed death ligand 1 (PD-L1) expression status.

EVIDENCE SYNTHESIS

Six trials were included in our network meta-analyses comprising 5121 patients. Nivolumab plus cabozantinib had the highest likelihood of providing the maximal OS (P score: 0.7573). Lenvatinib plus pembrolizumab demonstrated the highest likelihood of PFS (P score: 0.9906) and ORR (P score: 0.9564). CRRs were more likely to be associated with nivolumab plus ipilimumab (P score: 0.8682). In patients with ≥1% PD-L1 expression, the highest likelihood of better PFS was associated with lenvatinib plus pembrolizumab and nivolumab plus ipilimumab. Nivolumab plus ipilimumab was also associated with the lowest rates of grade ≥3 TRAEs; while the highest likelihood of AE-related treatment discontinuation was associated with lenvatinib plus pembrolizumab and nivolumab plus ipilimumab.

CONCLUSIONS

Our network meta-analysis suggests that combinations of ICIs and tyrosine kinase inhibitors (TKIs) provide superior PFS, ORR, and OS to ICI-ICI combinations, regardless of the on International mRCC Database Consortium risk group. However, an ICI-ICI combination could be the optimal treatment for tumors with increased PD-L1 expression. The newly introduced ICI-TKI combinations, nivolumab plus cabozantinib and lenvatinib plus pembrolizumab, showed promising activity and are likely to have an important role in the mRCC treatment strategy.

PATIENT SUMMARY

The use of immune checkpoint inhibitor (ICI)-based combinations (ICI plus tyrosine kinase inhibitor and ICI-ICI) improved oncological outcomes of metastatic renal cell carcinoma. Programmed death ligand 1 (PD-L1) expression status could help guide physicians and patients to select the appropriate treatment strategy.

Association of Survival and Immune-Related Adverse Events With Anti-PD-1/PD-L1 and Anti-CTLA-4 Inhibitors, Alone or Their Combination for the Treatment of Cancer: A Systematic Review and Meta-Analysis of 13 Clinical Trials

Background

Cancer, with sustained high mortality, is a worldwide threat to public health. Despite the survival benefit over conventional therapies shown in immune checkpoint inhibitor (ICI), only a minority of patients benefit from single ICI. But combination therapy holds the promise of achieving better efficacy over monotherapy. We performed a systematic review and meta-analysis to assess the efficacy and safety of ICI-based combination therapy for cancer.

Methods

A search was conducted to retrieve relevant studies in electronic databases and major conferences. Two investigators independently performed data extraction, making a systematic data extraction, assembly, analysis and interpretation to compare the overall survival (OS), progression-free survival (PFS), overall response rate (ORR), all and high grade immune related adverse events (IRAEs) between combination therapy and monotherapy. Therefore, only the studies satisfying the criteria were included. Finally, we performed subgroup, sensitivity, and publication bias analysis to examine the heterogeneity and bias of resources.

Results

A total of 2,532 patients from thirteen studies were enrolled. Compared to ICI alone, combination therapy, with a high risk and high grade IRAEs for the majority of all, offers a better survival benefit (OS: HR: 0.86, 95% CI: 0.76 to 0.98; PFS: HR: 0.79, 95% CI: 0.69 to 0.90) and objective response (ORR: RR: 1.91, 95% CI: 1.40 to 2.60).

Conclusions

ICI-based combination therapy was confirmed as the optimum treatment for cancer, especially when using specific dosage and regimen to treat certain tumor types with no absolute demand for the detection of PD-L1 expression. Meanwhile, attention should also be paid on potential toxicity, especially the IRAEs.

Targeting the tumour microenvironment in platinum-resistant ovarian cancer

Ovarian cancer typically presents at an advanced stage, and although the majority of cases initially respond well to platinum-based therapies, chemoresistance almost always occurs leading to a poor long-term prognosis. While various cellular autonomous mechanisms contribute to intrinsic or acquired platinum resistance, the tumour microenvironment (TME) plays a central role in resistance to therapy and disease progression by providing cancer stem cell niches, promoting tumour cell metabolic reprogramming, reducing chemotherapy drug perfusion and promoting an immunosuppressive environment. As such, the TME is an attractive therapeutic target which has been the focus of intense research in recent years. This review provides an overview of the unique ovarian cancer TME and its role in disease progression and therapy resistance, highlighting some of the latest preclinical and clinical data on TME-targeted therapies. In particular, it focuses on strategies targeting cancer-associated fibroblasts, tumour-associated macrophages, cancer stem cells and cancer cell metabolic vulnerabilities.

Development of Possible Next Line of Systemic Therapies for Gemcitabine-Resistant Biliary Tract Cancers: A Perspective from Clinical Trials

Biliary tract cancer (BTC) compromises a heterogenous group of tumors with poor prognoses. Curative surgery remains the first choice for localized disease; however, most BTC patients have had unresectable or metastatic disease. The gold standard therapy for these patients is chemotherapy with gemcitabine and cisplatin. There are no consensus guidelines for standard treatment in a second-line setting, although the data of the ABC-06 trial showed a slight survival benefit from oxaliplatin and 5-fluorouracil combination chemotherapy. Recent progress in comprehensive genomic profiling for advanced BTC (ABTC) has helped to clarify tumorigenesis and facilitate the coming era of precision medicine. Generally, targeted agents fail to show significant clinical benefits in unselected populations. Only fibroblast growth factor receptor 2 (FGFR2) fusion and isocitrate dehydrogenase (IDH)- and BRAF mutation-enriched populations have survival benefits from the corresponding inhibitors. Several interesting targeted agents for monotherapies or combination therapies with other compounds are currently ongoing or recruiting. Here, we review the published data from clinical trials of second-line therapies after the failure of gemcitabine-based chemotherapy in ABTC. The results were stratified by different genetic alternations, as well as by chemotherapy, targeted therapy and immunotherapy.

Silencing of VEGFR2 by RGD-Modified Lipid Nanoparticles Enhanced the Efficacy of Anti-PD-1 Antibody by Accelerating Vascular Normalization and Infiltration of T Cells in Tumors

Simple Summary

siRNA delivery to tumor endothelial cells was achieved using arginyl-glycyl-aspartic acid (RGD)-modified lipid nanoparticles containing a novel pH-sensitive and biodegradable lipid. The anti-tumor efficacy of an immune checkpoint inhibitor was improved by the silencing of VEGFR2 using the delivery system, because the combination therapy induced vascular normalization and increased CD8+ T cell infiltration into tumors. The efficient delivery of nucleic acids is a promising strategy to improve therapeutic outcomes in immune checkpoint inhibitor-resistant cancers.

Abstract

Despite the promising anticancer effects of immune checkpoint inhibitors, their low objective response rate remains to be resolved; thus, combination therapies have been investigated. We investigated the combination of an anti-programmed cell death 1 (aPD-1) monoclonal antibody with the knockdown of vascular endothelial factor receptor 2 (VEGFR2) on tumor endothelial cells to overcome resistance to immune checkpoint inhibitors and improve the objective response rate. The successful delivery of small interfering RNA to tumor endothelial cells was achieved by RGD peptide-modified lipid nanoparticles composed of a novel, pH-sensitive, and biodegradable ssPalmO-Phe. RGD-modified lipid nanoparticles efficiently induced the knockdown of VEGFR2 in tumor endothelial cells (TECs), which induced vascular normalization. The combination of a PD-1 monoclonal antibody with Vegfr2 knockdown enhanced CD8+ T cell infiltration into tumors and successfully suppressed tumor growth and improved response rate compared with monotherapy. Our combination approach provides a promising strategy to improve therapeutic outcomes in immune checkpoint inhibitor-resistant cancers.