Bevacizumab plus ipilimumab in patients with metastatic melanoma

Dynamic contrast-enhanced breast MRI features correlate with invasive breast cancer angiogenesis

Angiogenesis is a critical component of breast cancer development, and identification of imaging-based angiogenesis assays has prognostic and treatment implications. We evaluated the association of semi-quantitative kinetic and radiomic breast cancer features on dynamic contrast-enhanced (DCE)-MRI with microvessel density (MVD), a marker for angiogenesis. Invasive breast cancer kinetic features (initial peak percent enhancement [PE], signal enhancement ratio [SER], functional tumor volume [FTV], and washout fraction [WF]), radiomics features (108 total features reflecting tumor morphology, signal intensity, and texture), and MVD (by histologic CD31 immunostaining) were measured in 27 patients (1/2016-7/2017). Lesions with high MVD levels demonstrated higher peak SER than lesions with low MVD (mean: 1.94 vs. 1.61, area under the receiver operating characteristic curve [AUC] = 0.79, p = 0.009) and higher WF (mean: 50.6% vs. 22.5%, AUC = 0.87, p = 0.001). Several radiomics texture features were also promising for predicting increased MVD (maximum AUC = 0.84, p = 0.002). Our study suggests DCE-MRI can non-invasively assess breast cancer angiogenesis, which could stratify biology and optimize treatments.

Integrated approaches for precision oncology in colorectal cancer: The more you know, the better

Colorectal cancer (CRC) is one of the most common human malignancies accounting for approximately 10 % of worldwide cancer incidence and mortality. While early-stage CRC is mainly a preventable and curable disease, metastatic colorectal cancer (mCRC) remains an unmet clinical need. Moreover, about 25 % of CRC cases are diagnosed only at the metastatic stage. Despite the extensive molecular and functional knowledge on this disease, systemic therapy for mCRC still relies on traditional 5-fluorouracil (5-FU)-based chemotherapy regimens. On the other hand, targeted therapies and immunotherapy have shown effectiveness only in a limited subset of patients. For these reasons, there is a growing need to define the molecular and biological landscape of individual patients to implement novel, rationally driven, tailored therapies. In this review, we explore current and emerging approaches for CRC management such as genomic, transcriptomic and metabolomic analysis, the use of liquid biopsies and the implementation of patients' preclinical avatars. In particular, we discuss the contribution of each of these tools in elucidating patient specific features, with the aim of improving our ability in advancing the diagnosis and treatment of colorectal tumors.

Angiogenesis as a hallmark of solid tumors - clinical perspectives

BACKGROUND

Angiogenesis is a key and early step in tumorigenesis, and is known as a hallmark of solid tumors and a key promoter of tumor recurrence. Unlike normal tissue vessels, the architecture of the tumor vasculature is abnormal, being leaky, tortuous, fragile and blind-ended. Perivascular cells are either detached or absent, causing reduction of vascular integrity, an increase in vessel immaturity, incoherent perfusion, defective functionality and enhanced tumor dissemination and metastasis. The abnormal tumor vasculature along with the defective tumor vessel functionality finally causes bouts of hypoxia and acidity in the tumor microenvironment (TME), further reinvigorating tumor aggression. Interstitial hypertension or high interstitial fluid pressure (IFP) is an outcome of tumor hyper-permeability. High IFP can be a barrier for either effective delivery of anti-cancer drugs toward the TME or accumulation of drugs within the tumor area, thus promoting tumor resistance to therapy. Some tumors do, however, not undergo angiogenesis but instead undergo vessel co-option or vascular mimicry, thereby adding another layer of complexity to cancer development and therapy.

CONCLUSIONS

Combination of anti-angiogenesis therapy with chemotherapy and particularly with immune checkpoint inhibitors (ICIs) is a promising strategy for a number of advanced cancers. Among the various approaches for targeting tumor angiogenesis, vascular normalization is considered as the most desired method, which allows effective penetration of chemotherapeutics into the tumor area, thus being an appropriate adjuvant to other cancer modalities.

Efficacy and Safety of First-Line Immunotherapy Combinations for Advanced NSCLC: A Systematic Review and Network Meta-Analysis

INTRODUCTION

A series of randomized controlled trials have investigated different first-line immunotherapy combinations, but the optimal combination strategy is yet to be established.

METHODS

We performed a systematic review and Bayesian network meta-analysis by retrieving relevant literature from PubMed, EMBASE, Cochrane Library, ClinicalTrials.gov, and major international conferences. We included published and gray sources of randomized clinical trials comparing immunotherapy combinations with other treatments as first-line treatments for patients with advanced NSCLC. This study was registered in the Prospective Register of Systematic Reviews (CRD42020210501) to ensure transparency.

RESULTS

We analyzed a total of 16 studies involving 8278 patients and including 10 immunotherapy combinations. For patients without programmed death-ligand 1 (PD-L1) selection, pembrolizumab plus chemotherapy was found to be comparable with sintilimab plus chemotherapy in providing the best overall survival (OS) benefit (hazard ratio = 0.96, 95% confidence interval [CI]: 0.72-1.29). Furthermore, atezolizumab plus bevacizumab plus chemotherapy seemed to provide the best progression-free survival (hazard ratio = 0.45, 95% CI: 0.36-0.55) and the best objective response rate (OR = 0.23, 95% CI: 0.12-0.42). Subgroup analysis by PD-L1 suggested that nivolumab plus ipilimumab plus chemotherapy was associated with the best OS in patients with PD-L1 less than 1% and that pembrolizumab plus chemotherapy was associated with the best OS in patients with PD-L1 greater than or equal to 1%. Pembrolizumab and sintilimab were associated with relatively fewer grade greater than or equal to 3 adverse events when compared with other immunotherapies combined with chemotherapy.

CONCLUSIONS

Our results suggest that antiprogrammed death-1 combinations are associated with potentially higher survival outcomes than anti-PD-L1 combinations with comparable safety profiles. Moreover, pem-chemo and nivo-ipi-chemo seem to be superior first-line immunotherapy combinations for patients with advanced NSCLC with positive and negative PD-L1 expression, respectively. Although atezo-beva-chemo treatment provided the best progression-free survival and objective response rate, the addition of chemotherapy to immunotherapy would increase the toxicity, especially when antiangiogenesis drugs are simultaneously added.

Enhanced anti-PD-1 therapy in hepatocellular carcinoma by tumor vascular disruption and normalization dependent on combretastatin A4 nanoparticles and DC101

Anti-programmed cell death protein 1 (PD-1) therapy has shown promising efficacy in hepatocellular carcinoma (HCC), but its response rates in advanced HCC are lower than 20%. A critical reason for this is the imbalance between CD8⁺ T cells and tumor burden. Here, a novel concept of vascular disruption and normalization dependent on a polymeric vascular disrupting agent (VDA) poly (_L-glutamic acid)-graft-methoxy poly (ethylene glycol)/combretastatin A4 (CA4-NPs) + a vascular endothelial growth factor (VEGF)/VEGF receptor 2 (VEGFR2) inhibitor DC101 is applied to improve anti-PD-1 therapy, wherein CA4-NPs reduce tumor burden and DC101 simultaneously increases the number of intratumoral CD8⁺ T cells, successfully regulating the abovementioned imbalance in an H22 tumor model.

Methods: Blood vessel density, tumor cell proliferation, and necrosis were evaluated to reveal the effects on reducing tumor burden by CA4-NP treatment. Pericyte coverage of blood vessels, tumor blood vessel perfusion, tumor hypoxia, and intratumoral immune cells were examined to verify their role in vascular normalization and immune cell homing of DC101. Furthermore, the effects of CA4-NPs + DC101 on reducing tumor burden and increasing the number of immune cells were studied. Finally, tumor suppression, intratumoral CD8⁺ T cell activation, and the synergistic effects of anti-PD-1 combined with CA4-NPs + DC101 were verified.

Results: The tumor inhibition rate of anti-PD-1 antibody combined with CA4-NPs + DC101 reached 86.4%, which was significantly higher than that of anti-PD-1 (16.8%) alone. Importantly, the Q value reflecting the synergy between CA4-NPs + DC101 and anti-PD-1 was 1.24, demonstrating a strong synergistic effect. Furthermore, CA4-NPs + DC101 improved anti-PD-1 therapy by increasing the number of intratumoral CD8⁺ T cells (anti-PD-1, 0.31% vs triple drug combination, 1.18%).

Conclusion: These results reveal a novel approach to enhance anti-PD-1 therapy with VDAs + VEGF/VEGFR2 inhibitors in HCC.

ARID1A Deficiency Is Associated With High Programmed Death Ligand 1 Expression in Hepatocellular Carcinoma

The clinicopathological features of carcinomas expressing AT-rich interaction domain 1a (ARID1A) and programmed death ligand 1 (PD-L1) in HCC are poorly understood. Here, we examined ARID1A and PD-L1 expression in surgically resected primary hepatocellular carcinoma (HCC) and the association of ARID1A and PD-L1 expression with clinicopathological features and patient outcomes. Their association with ARID1A expression and tumor-associated CD68-positive macrophage was further explored. Using a database of 255 patients who underwent hepatic resection for HCC, immunohistochemical staining of ARID1A, PD-L1, and CD68 was performed. We also analyzed the expression PD-L1 after ARID1A knockdown in HCC cell lines. Samples from 81 patients (31.7%) were negative for ARID1A. Negative ARID1A expression was significantly associated with male sex, high alpha-fetoprotein, high des-gamma-carboxyprothrombin, large tumor size, high rate of poor differentiation, microscopic intrahepatic metastasis, and PD-L1 expression. In addition, negative ARID1A expression was an independent predictor for recurrence-free survival, overall survival, and positive PD-L1 expression. Stratification based on ARID1A and PD-L1 expression in cancer cells was also significantly associated with unfavorable outcomes. PD-L1 protein expression levels were increased through phosphoinositide 3-kinase/AKT signaling after ARID1A knockdown in HCC cells. HCC with ARID1A-low expression was significantly correlated with high levels of tumor-associated CD68-positive macrophage. Conclusion: Our large cohort study showed that ARID1A expression in cancer cells was associated with a poor clinical outcome in patients with HCC, PD-L1 expression in cancer cells, and tumor microenvironment. Therefore, ARID1A may be a potential molecular biomarker for the selection of patients with HCC for anti-programmed death 1/PD-L1 antibody therapy.

Hypophysitis related to immune checkpoint inhibitors: An intriguing adverse event with many faces

INTRODUCTION

The incorporation of immune checkpoint inhibitors in the oncologists' arsenal is a milestone in cancer therapeutics, though not being devoid of toxicities.Areas covered: The present review provides a comprehensive and up-to-date overview of the immune-related hypophysitis with focus on the elusive biological background, the wide spectrum of the epidemiological profile, the varying clinical aspects, and the diagnostic and therapeutic challenges.Expert opinion: Historically considered distinctive of anti-cytotoxic T-lymphocyte antigen 4 (CTLA-4) monoclonal antibodies (mAbs), the immune-related hypophysitis is increasingly correlated with the anti-programmed cell-death (PD) protein 1 (PD-1)/anti-PD ligand 1 (PD-L1) mAbs. The distinct phenotype of hypophysitis related to anti-PD1/anti-PD-L1 mAbs is highlighted with focus on the immune-related isolated adrenocorticotropic (ACTH) deficiency. The immune-related central diabetes insipidus is discussed as a rare aspect of anti-CTL-A4 mAbs-induced hypophysitis, recently related to anti-PD1/anti-PD-L1 mAbs as well. The present review builds on existing literature concerning immune-related hypophysitis underscoring the pending issues still to be addressed, including (i) pathogenesis; (ii) correlation with preexisting autoimmunity; (iii) predictive value; (iv) utility of high-dose glucocorticoids; and (v) establishment of evidence-based diagnostic and therapeutic protocols. Increased awareness and constant vigilance are advocated as cornerstone of a multidisciplinary approach to ensure optimal patients' care.

Ocular Toxicity of Targeted Anticancer Agents

The proliferation of targeted anticancer agents over the last two decades has revolutionized cancer treatment and improved survival in many previously refractory malignancies. However, many agents are associated with characteristic ophthalmic adverse effects. It is important that ophthalmologists recognize and maintain a high index of suspicion for these side effects in patients on targeted therapy. Most ophthalmic adverse effects can be treated with specific ocular therapy without discontinuation of cancer treatment, although it is important to be aware of the life-threatening and vision-threatening circumstances that would require therapy cessation in conjunction with the patient's oncologist. This review aims to summarize the ophthalmic adverse effects of targeted and hormonal anticancer agents and briefly describe their management.

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.

BRAF Gene and Melanoma: Back to the Future

As widely acknowledged, 40-50% of all melanoma patients harbour an activating BRAF mutation (mostly BRAF V600E). The identification of the RAS-RAF-MEK-ERK (MAP kinase) signalling pathway and its targeting has represented a valuable milestone for the advanced and, more recently, for the completely resected stage III and IV melanoma therapy management. However, despite progress in BRAF-mutant melanoma treatment, the two different approaches approved so far for metastatic disease, immunotherapy and BRAF+MEK inhibitors, allow a 5-year survival of no more than 60%, and most patients relapse during treatment due to acquired mechanisms of resistance. Deep insight into BRAF gene biology is fundamental to describe the acquired resistance mechanisms (primary and secondary) and to understand the molecular pathways that are now being investigated in preclinical and clinical studies with the aim of improving outcomes in BRAF-mutant patients.

Thinking Small: Small Molecules as Potential Synergistic Adjuncts to Checkpoint Inhibition in Melanoma

Metastatic melanoma remains the deadliest form of skin cancer. Immune checkpoint inhibition (ICI) immunotherapy has defined a new age in melanoma treatment, but responses remain inconsistent and some patients develop treatment resistance. The myriad of newly developed small molecular (SM) inhibitors of specific effector targets now affords a plethora of opportunities to increase therapeutic responses, even in resistant melanoma. In this review, we will discuss the multitude of SM classes currently under investigation, current and prospective clinical combinations of ICI and SM therapies, and their potential for synergism in melanoma eradication based on established mechanisms of immunotherapy resistance.

Systemic immunity markers associated with lymphocytes predict the survival benefit from paclitaxel plus bevacizumab in HER2 negative advanced breast cancer

Although paclitaxel plus bevacizumab (PB) therapy is an effective chemotherapeutic regimen for HER2-negative advanced breast cancer (ABC), predictive markers for its effectiveness remain undefined. We investigated the usefulness of systemic immunity markers associated with lymphocytes as predictive markers for PB therapy in patients with HER2-negative ABC. We retrospectively reviewed data from 114 patients with HER2-negative ABC who underwent PB therapy from November 2011 to December 2019. We calculated the absolute lymphocyte count (ALC), neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and lymphocyte-to-monocyte ratio (LMR) as representative systemic immunity markers. The time to treatment failure (TTF) and overall survival (OS) of the patients with high ALC, low NLR, and high LMR were significantly longer compared with those of the patients with low ALC, high NLR, and low LMR. A multivariable analysis revealed that high ALC, low NLR, and low PLR were independent predictors for TTF and high ALC, low NLR, and high LMR were independent predictors for OS. Systemic immunity markers were significantly associated with longer TTF and OS in patients who underwent PB therapy and may represent predictive markers for PB therapy in patients with HER2-negative ABC.

Immunotherapy as a treatment strategy in advanced stage and recurrent endometrial cancer: review of current phase III immunotherapy clinical trials

The treatment of advanced stage, metastatic or recurrent endometrial cancer remains a clinically difficult scenario. Although combination carboplatin and paclitaxel is an effective standard-of-care regimen, alternate strategies have shown promise, particularly in biomarker select populations. In an effort to improve oncologic outcomes, investigators are exploring novel immunotherapy combinations. In this review, we discuss the clinical rationale and design of current phase III immuno-oncology clinical trials in patients with advanced stage or recurrent endometrial cancer.

Resistance to Molecularly Targeted Therapies in Melanoma

Malignant melanoma is the most aggressive type of skin cancer with invasive growth patterns. In 2021, 106,110 patients are projected to be diagnosed with melanoma, out of which 7180 are expected to die. Traditional methods like surgery, radiation therapy, and chemotherapy are not effective in the treatment of metastatic and advanced melanoma. Recent approaches to treat melanoma have focused on biomarkers that play significant roles in cell growth, proliferation, migration, and survival. Several FDA-approved molecular targeted therapies such as tyrosine kinase inhibitors (TKIs) have been developed against genetic biomarkers whose overexpression is implicated in tumorigenesis. The use of targeted therapies as an alternative or supplement to immunotherapy has revolutionized the management of metastatic melanoma. Although this treatment strategy is more efficacious and less toxic in comparison to traditional therapies, targeted therapies are less effective after prolonged treatment due to acquired resistance caused by mutations and activation of alternative mechanisms in melanoma tumors. Recent studies focus on understanding the mechanisms of acquired resistance to these current therapies. Further research is needed for the development of better approaches to improve prognosis in melanoma patients. In this article, various melanoma biomarkers including BRAF, MEK, RAS, c-KIT, VEGFR, c-MET and PI3K are described, and their potential mechanisms for drug resistance are discussed.

Immunotherapy for the treatment of colorectal cancer

Immune checkpoint inhibition (ICI) has transformed the management of metastatic colorectal cancer (mCRC) with mismatch-repair deficiency (dMMR) and microsatellite instability (MSI-H), though this constitutes on average less than 5% of mCRC, and ICI is ineffective in preserved MMR/microsatellite stable disease (pMMR/MSS). Here we review the efficacy of ICI in dMMR/MSI-H mCRC, poor response to ICI in pMMR/MSS mCRC, role for ICI in locally advanced disease, biomarkers of response, novel immunotherapies, and future directions in targeting resistance mechanisms.

Anti-Tumoral and Anti-Angiogenic Effects of Low-Diluted Phenacetinum on Melanoma

Melanoma is the most aggressive form of skin cancer and the most rapidly expanding cancer in terms of worldwide incidence. If primary cutaneous melanoma is mostly treated with a curative wide local excision, malignant melanoma has a poor prognosis and needs other therapeutic approaches. Angiogenesis is a normal physiological process essential in growth and development, but it also plays a crucial role in crossing from benign to advanced state in cancer. In melanoma progression, angiogenesis is widely involved during the vertical growth phase. Currently, no anti-angiogenic agents are efficient on their own, and combination of treatments will probably be the key to success. In the past, phenacetin was used as an analgesic to relieve pain, causing side effects at large dose and tumor-inducing in humans and animals. By contrast, Phenacetinum low-dilution is often used in skin febrile exanthema, patches profusely scattered on limbs, headache, or flushed face without side effects. Herein are described the in vitro, in vivo, and ex vivo anti-angiogenic and anti-tumoral potentials of Phenacetinum low-dilution in a B16F1 tumor model and endothelial cells. We demonstrate that low-diluted Phenacetinum inhibits in vivo tumor growth and tumor vascularization and thus increases the survival time of B16F1 melanoma induced-C57BL/6 mice. Moreover, Phenacetinum modulates the lung metastasis in a B16F10 induced model. Ex vivo and in vitro, we evidence that low-diluted Phenacetinum inhibits the migration and the recruitment of endothelial cells and leads to an imbalance in the pro-tumoral macrophages and to a structural malformation of the vascular network. All together these results demonstrate highly hopeful anti-tumoral, anti-metastatic, and anti-angiogenic effects of Phenacetinum low-dilution on melanoma. Continued studies are needed to preclinically validate Phenacetinum low-dilution as a complementary or therapeutic strategy for melanoma treatment.

Nanomaterials Enhance the Immunomodulatory Effect of Molecular Targeted Therapy

Molecular targeted therapy, a tumor therapy strategy that inhibits specific oncogenic targets, has been shown to modulate the immune response. In addition to directly inhibiting the proliferation and metastasis of tumor cells, molecular targeted drugs can activate the immune system through a variety of mechanisms, including by promoting tumor antigen processing and presentation, increasing intratumoral T cell infiltration, enhancing T cell activation and function, and attenuating the immunosuppressive effect of the tumor microenvironment. However, poor water solubility, insufficient accumulation at the tumor site, and nonspecific targeting of immune cells limit their application. To this end, a variety of nanomaterials have been developed to overcome these obstacles and amplify the immunomodulatory effects of molecular targeted drugs. In this review, we summarize the impact of molecular targeted drugs on the antitumor immune response according to their mechanisms, highlight the advantages of nanomaterials in enhancing the immunomodulatory effect of molecular targeted therapy, and discuss the current challenges and future prospects.

Druggable genome and precision medicine in cancer: current challenges

The past decades have seen tremendous developments with respect to "specific" therapeutics that target key signaling molecules to conquer cancer. The key advancements with multiomics technologies, especially genomics, have allowed physicians and molecular oncologists to design "tailor-made" solutions to the specific oncogenes that are deregulated in individual patients, a strategy which has turned out to be successful though the patients quickly develop resistance. The swift integration of multidisciplinary approaches has led to the development of "next generation" therapeutics and, with synergistic therapeutic regimes combined with immune checkpoint inhibitors to reactivate the dampened immune response, has provided the much-needed promise for cancer patients. Despite these advances, a large portion of the druggable genome remains understudied, and the role of druggable genome in the immune system needs further attention. Establishment of patient-derived organoid models has fastened the preclinical validation of novel therapeutics for swift clinical translation. We summarized the current advances and challenges and also stress the importance of biobanking and collection of longitudinal data sets with structured clinical information, as well as the critical role these "high content data sets" will play in designing new therapeutic regimes in a tailor-made fashion.

Ocular surface disease associated with immune checkpoint inhibitor therapy

Immune-related adverse events (irAEs) is a term used to describe the various toxicities associated with immune checkpoint inhibitor (ICI) use. As this class of cancer immunotherapy grows, the diversity of documented irAEs also continues to expand. Ocular toxicities secondary to ICI use are relatively rare, with dry eye and uveitis as the most frequently reported ocular side effects. This article specifically investigates the relationship between ocular surface disease and ICI therapy through a review of the existing literature. Dry eye disease (DED), conjunctivitis, and keratitis were the most commonly reported irAEs affecting the ocular surface across the 29 studies reviewed. Keratoplasty graft rejection was also described in two case reports. Our review of eight clinical trials found the incidence of DED, the most common ocular surface irAE, to range from 1 to 4%. Nearly all cases of ocular surface irAEs were graded as mild or moderate in severity and were often self-limited or controlled with conservative treatment. Duration of checkpoint inhibitor use prior to onset of ocular surface side effects varied widely, ranging from days to months. Ocular surface toxicities associated with checkpoint immunotherapy appear to be under-reported and under-investigated. Further work remains to be done to investigate the full breadth of ocular surface pathologies and the molecular mechanisms by which these toxicities occur.

Exhausted CD8+T Cells in the Tumor Immune Microenvironment: New Pathways to Therapy

Tumor-specific CD8⁺T cells are exposed to persistent antigenic stimulation which induces a dysfunctional state called "exhaustion." Though functioning to limit damage caused by immune response, T cell exhaustion leads to attenuated effector function whereby cytotoxic CD8⁺T cells fail to control tumor progression in the late stage. This pathway is a dynamic process from activation to "progenitor exhaustion" through to "terminally exhaustion" with distinct properties. With the rapid development of immunotherapy via enhancing T cell function, new studies are dissecting the mechanisms and identifying specific biomarkers of dynamic differentiation during the process of exhaustion. Further, although immune checkpoint inhibitors (ICIs) have achieved great success in clinical practice, most patients still show limited efficacy to ICIs. The expansion and differentiation of progenitor exhausted T cells explained the success of ICIs while the depletion of the progenitor T cell pool and the transient effector function of terminally exhausted T cells accounted for the failure of immune monotherapy in the context of exorbitant tumor burden. Thus, combination strategies are urgent to be utilized based on the reduction of tumor burden or the expansion of the progenitor T cell pool. In this review, we aim to introduce the concept of homeostasis of the activated and exhausted status of CD8⁺T cells in the tumor immune microenvironment, and present recent findings on dynamic differentiation process during T cell exhaustion and the implications for combination strategies in immune therapy.

Case Report: Pseudoprogression With Nivolumab and Bevacizumab Followed by Recurrent Immune-Related Pneumonitis in Urothelial Carcinoma With Lung Metastasis

Background

Combination therapy with immune checkpoint inhibitors (ICIs) and antiangiogenic agents is generally effective and well tolerated and might be effective for metastatic urothelial carcinoma (UC). However, ICI treatment is often associated with unique responses, such as pseudoprogression and ICI-related pneumonitis (CIP), which may influence clinical decision making and affect treatment. Although there have been many studies on the mechanism of pseudoprogression and CIP, the characteristics and relationship of these special events in a clinical setting remain rarely reported.

Case Presentation

Here, we present a patient with lung metastatic UC who underwent surgery and two lines of chemotherapy. The programmed cell death-1 (PD-1) inhibitor nivolumab and antiangiogenics agent bevacizumab were used as maintenance treatments. The patient experienced pseudoprogression after 2 PD-1 inhibitor cycles. The lesions in both lungs were enlarged on computed tomography (CT) imaging, and treatments were continued for another two cycles, after which the tumor size decreased to below baseline, followed by a durable response. However, after 4 months of pseudoprogression, the patient then developed CIP. The CIP was responsive to glucocorticoid therapy but recurred during ICI rechallenge, leading to the termination of immune therapy. Ultimately, the patient achieved durable, stable disease for over 18 months without further anticancer treatment.

Conclusions

Our case shows that pseudoprogression can occur in UC during immunotherapy even when combined with an effective antiangiogenic agent. In addition, pseudoprogression may be correlated with future adverse effects and a durable response. In the management of CIP, early rechallenge with ICIs may lead to CIP recurrence, which could be more severe and needs to be treated early and with appropriate drugs. Clinicians should be aware of atypical responses to ICIs and adjust the treatment plan accordingly.

Addressing resistance to immune checkpoint inhibitor therapy: an urgent unmet need

Immune checkpoint inhibitors (ICIs) have revolutionized the treatment of various cancers by reversing the immunosuppressive mechanisms employed by tumors to restore anticancer immunity. Although ICIs have demonstrated substantial clinical efficacy, patient response can vary in depth and duration, and many do not respond at all or eventually develop resistance. ICI resistance mechanisms can be tumor-intrinsic, related to the tumor microenvironment or patient-specific factors. Multiple resistance mechanisms may be present within one tumor subtype, or heterogeneity exists among patients with the same tumor type. Consequently, designing effective combination treatment strategies is challenging. This review will discuss ICI resistance mechanisms, and summarize findings from key preclinical and clinical trials of ICIs, to identify potential treatment strategies or pathways to overcome ICI resistance.

A real-world study of the efficacy and safety of anti-programmed cell death-1 therapy combined with chemotherapy or targeted therapy in patients with advanced biliary tract cancer

Background

Immune checkpoint inhibitors (ICIs) represent a breakthrough in cancer treatment. However, they have rarely been used to treat biliary tract cancer (BTC). In the current study, we aimed to evaluate and compare the efficacy and safety of anti-programmed cell death-1 (PD-1) therapy used alone or in combination with chemotherapy or targeted therapy in the treatment of advanced BTC.

Methods

Patients with advanced BTC who were treated either with anti-PD-1 therapy alone or anti-PD-1 therapy plus chemotherapy or targeted therapy between December, 2015 and October, 2017 were retrospectively screened for eligibility. Patients who had previously received treatment with any agent targeting T-cell co-stimulation or immune checkpoints were excluded. Overall survival (OS), progression-free survival (PFS), objective response rate (ORR), and safety were evaluated.

Results

A total of 37 patients were included in this study (15 cases in the monotherapy group and 22 cases in the combination group). Patients in the combination group had significantly longer OS [median, 8.2 vs. 3.6 months, HR 0.47 (0.20-1.10), P=0.011] and PFS (median, 3.9 vs. 2.0 months, HR 0.58 (0.28-1.19), P=0.034) than patients in the monotherapy group. The ORR was 18.2% (4/22) and 0% in the combination group and monotherapy group, respectively, and the difference was not significant (P=0.131). Furthermore, no significant difference was found between the two groups with respect to the incidence of grade 3-4 treatment-related adverse events (P=0.388).

Conclusions

Anti-PD-1 therapy plus chemotherapy or targeted therapy is an effective and tolerable treatment for patients with advanced BTC and is promising as a first-line treatment or beyond.

Randomized Phase II Study of Bevacizumab in Combination With Carboplatin Plus Paclitaxel in Patients With Previously Untreated Advanced Mucosal Melanoma

PURPOSE

Mucosal melanoma (MM) is a highly vascularized tumor with an extremely poor prognosis. In this randomized, open-label, phase II study, we characterized the efficacy and safety of bevacizumab in combination with carboplatin plus paclitaxel (CPB) in patients with previously untreated advanced MM.

PATIENTS AND METHODS

Patients were randomly assigned in a 2:1 ratio to receive carboplatin (area under the curve, 5) plus paclitaxel (175 mg/m²) once every 4 weeks in combination with (CPB arm, 5 mg/kg) or without (CP arm) bevacizumab once every 2 weeks. Progression-free survival (PFS) was the primary end point. Secondary end points included overall survival (OS), objective response rate, and adverse events.

RESULTS

We recruited 114 patients to our study. The median PFS was significantly longer in the CPB arm (4.8 months; 95% CI, 3.6 to 6.0 months) than in the CP arm (3.0 months; 95% CI, 1.7 to 4.3 months) (hazard ratio, 0.461; 95% CI, 0.306 to 0.695; P < .001). Objective response rates were 19.7% and 13.2%, respectively (P = .384). The median OS was also significantly longer in the CPB arm than in the CP arm (13.6 v 9.0 months; hazard ratio, 0.611; 95% CI, 0.407 to 0.917; P = .017). No new safety signals were observed.

CONCLUSION

PFS and OS were significantly better in patients with metastatic MM who received bevacizumab in addition to CPB than in those who received CPB alone. A phase III study should be performed to confirm these benefits (ClinicalTrials.gov identifier: NCT02023710).

Ocular side effects of checkpoint inhibitors

The incidence and impact of ocular side effects in patients treated with checkpoint inhibitors are not clearly defined. We reviewed prospective phase III clinical trials of checkpoint inhibitors applied in lung cancer, renal cell cancer, and melanoma. Case reports of the occurrence of ocular toxicities in patients receiving immune checkpoint inhibitors were also included. Of the 35 articles corresponding to phase III clinical trials with checkpoint inhibitors, ocular toxicity was described in four. Forty-six clinical cases of ocular toxicity after therapy with checkpoint inhibitors have been reported. The most frequently described ocular toxicities are uveitis, inflammatory orbital disease, and alterations of the ocular surface. Ocular toxicity is underestimated in checkpoint inhibitors clinical trials. Early ophthalmic examination and treatment with corticosteroids may improve the visual prognosis in these patients.

Targeting hypoxia in the tumor microenvironment: a potential strategy to improve cancer immunotherapy

With the success of immune checkpoint inhibitors (ICIs), significant progress has been made in the field of cancer immunotherapy. Despite the long-lasting outcomes in responders, the majority of patients with cancer still do not benefit from this revolutionary therapy. Increasing evidence suggests that one of the major barriers limiting the efficacy of immunotherapy seems to coalesce with the hypoxic tumor microenvironment (TME), which is an intrinsic property of all solid tumors. In addition to its impact on shaping tumor invasion and metastasis, the hypoxic TME plays an essential role in inducing immune suppression and resistance though fostering diverse changes in stromal cell biology. Therefore, targeting hypoxia may provide a means to enhance the efficacy of immunotherapy. In this review, the potential impact of hypoxia within the TME, in terms of key immune cell populations, and the contribution to immune suppression are discussed. In addition, we outline how hypoxia can be manipulated to tailor the immune response and provide a promising combinational therapeutic strategy to improve immunotherapy.

Efficacy and safety of immunological checkpoint inhibitors combined with anti-angiogenic drugs in first-line treatment of metastatic renal cell carcinoma: a systematic review and meta-analysis

Background

Immune checkpoint inhibitors (ICIs) have shown promising results for the second-line treatment of metastatic renal cell carcinoma (mRCC). Several randomized controlled trials have so far also evaluated the efficacy of ICIs for first-line treatment of mRCC. In this study, we conducted a meta-analysis of relevant studies to further clarify the efficacy and safety of ICIs combined with anti-angiogenic drugs for the treatment of mRCC.

Methods

We searched the PubMed, Embase, and Cochrane libraries for RCT trials of ICIs combined with anti-angiogenic drugs for first-line treatment of mRCC published before November 20, 2019. A meta-analysis was conducted based on methodological recommendations by the Cochrane Collaboration.

Results

Four articles with a total of 2,967 patients met the inclusion criteria. Our meta-analysis revealed that progression-free survival (PFS) and objective response rate (ORR) were significantly improved in the experimental group while there was no significant difference in overall survival (OS) (HR 0.75, 95% CI: 0.67-0.84; HR 1.43, 95% CI: 1.07-1.91; HR 0.74, 95% CI: 0.53-1.03). After stratification for PD-L1 expression, OS, PFS, and ORR of PD-L1 positive patients were significantly increased in the experimental group (HR 0.74, 95% CI: 0.56-0.96; HR 1.66, 95% CI: 1.11-2.49; HR 0.65, 95% CI: 0.57-0.75).

Conclusions

Immunological checkpoint inhibitors combined with anti-angiogenic drugs as a first-line treatment for mRCC improve PFS and ORR. This effect is more pronounced in PD-L1 positive patients, where ICIs also improve OS. ICIs do not increase the incidence of adverse events.

Anti-Cancer Nanomedicines: A Revolution of Tumor Immunotherapy

Immunotherapies have been accelerating the development of anti-cancer clinical treatment, but its low objective responses and severe off-target immune-related adverse events (irAEs) limit the range of application. Strategies to remove these obstacles primarily focus on the combination of different therapies and the exploitation of new immunotherapeutic agents. Nanomedicine potentiates the effects of activating immune cells selectively and reversing tumor induced immune deficiency microenvironment through multiple mechanisms. In the last decade, a variety of nano-enabled tumor immunotherapies was under clinical investigation. As time goes by, the advantages of nanomedicine are increasingly prominent. With the continuous development of nanotechnology, nanomedicine will offer more distinctive perspectives in imaging diagnosis and treatment of tumors. In this Review, we wish to provide an overview of tumor immunotherapy and the mechanisms of nanomaterials that aim to enhance the efficacy of tumor immunotherapy under development or in clinic treatment.

Cytokine and Chemokine Signals of T-Cell Exclusion in Tumors

The success of cancer immunotherapy in solid tumors depends on a sufficient distribution of effector T cells into malignant lesions. However, immune-cold tumors utilize many T-cell exclusion mechanisms to resist immunotherapy. T cells have to go through three steps to fight against tumors: trafficking to the tumor core, surviving and expanding, and maintaining the memory phenotype for long-lasting responses. Cytokines and chemokines play critical roles in modulating the recruitment of T cells and the overall cellular compositions of the tumor microenvironment. Manipulating the cytokine or chemokine environment has brought success in preclinical models and early-stage clinical trials. However, depending on the immune context, the same cytokine or chemokine signals may exhibit either antitumor or protumor activities and induce unwanted side effects. Therefore, a comprehensive understanding of the cytokine and chemokine signals is the premise of overcoming T-cell exclusion for effective and innovative anti-cancer therapies.

Therapeutic strategies to remodel immunologically cold tumors

Immune checkpoint inhibitors (ICIs) induce a durable response in a wide range of tumor types, but only a minority of patients outside these ‘responsive’ tumor types respond, with some totally resistant. The primary predictor of intrinsic immune resistance to ICIs is the complete or near‐complete absence of lymphocytes from the tumor, so‐called immunologically cold tumors. Here, we propose two broad approaches to convert ‘cold’ tumors into ‘hot’ tumors. The first is to induce immunogenic tumor cell death, through the use of oncolytic viruses or bacteria, conventional cancer therapies (e.g. chemotherapy or radiation therapy) or small molecule drugs. The second approach is to target the tumor microenvironment, and covers diverse options such as depleting immune suppressive cells; inhibiting transforming growth factor‐beta; remodelling the tumor vasculature or hypoxic environment; strengthening the infiltration and activation of antigen‐presenting cells and/or effector T cells in the tumor microenvironment with immune modulators; and enhancing immunogenicity through personalised cancer vaccines. Strategies that successfully modify cold tumors to overcome their resistance to ICIs represent mechanistically driven approaches that will ultimately result in rational combination therapies to extend the clinical benefits of immunotherapy to a broader cancer cohort.

The Angiopoietin-2 and TIE Pathway as a Therapeutic Target for Enhancing Antiangiogenic Therapy and Immunotherapy in Patients with Advanced Cancer

Despite significant advances made in cancer treatment, the development of therapeutic resistance to anticancer drugs represents a major clinical problem that limits treatment efficacy for cancer patients. Herein, we focus on the response and resistance to current antiangiogenic drugs and immunotherapies and describe potential strategies for improved treatment outcomes. Antiangiogenic treatments that mainly target vascular endothelial growth factor (VEGF) signaling have shown efficacy in many types of cancer. However, drug resistance, characterized by disease recurrence, has limited therapeutic success and thus increased our urgency to better understand the mechanism of resistance to inhibitors of VEGF signaling. Moreover, cancer immunotherapies including immune checkpoint inhibitors (ICIs), which stimulate antitumor immunity, have also demonstrated a remarkable clinical benefit in the treatment of many aggressive malignancies. Nevertheless, the emergence of resistance to immunotherapies associated with an immunosuppressive tumor microenvironment has restricted therapeutic response, necessitating the development of better therapeutic strategies to increase treatment efficacy in patients. Angiopoietin-2 (ANG2), which binds to the receptor tyrosine kinase TIE2 in endothelial cells, is a cooperative driver of angiogenesis and vascular destabilization along with VEGF. It has been suggested in multiple preclinical studies that ANG2-mediated vascular changes contribute to the development and persistence of resistance to anti-VEGF therapy. Further, emerging evidence suggests a fundamental link between vascular abnormalities and tumor immune evasion, supporting the rationale for combination strategies of immunotherapy with antiangiogenic drugs. In this review, we discuss the recent mechanistic and clinical advances in targeting angiopoietin signaling, focusing on ANG2 inhibition, to enhance therapeutic efficacy of antiangiogenic and ICI therapies. In short, we propose that a better mechanistic understanding of ANG2-mediated vascular changes will provide insight into the significance of ANG2 in treatment response and resistance to current antiangiogenic and ICI therapies. These advances will ultimately improve therapeutic modalities for cancer treatment.

Randomized Phase II and Biomarker Study of Pembrolizumab plus Bevacizumab versus Pembrolizumab Alone for Patients with Recurrent Glioblastoma

PURPOSE

VEGF is upregulated in glioblastoma and may contribute to immunosuppression. We performed a phase II study of pembrolizumab alone or with bevacizumab in recurrent glioblastoma.

PATIENTS AND METHODS

Eighty bevacizumab-naïve patients with recurrent glioblastoma were randomized to pembrolizumab with bevacizumab (cohort A, n = 50) or pembrolizumab monotherapy (cohort B, n = 30). The primary endpoint was 6-month progression-free survival (PFS-6). Assessed biomarkers included evaluation of tumor programmed death-ligand 1 expression, tumor-infiltrating lymphocyte density, immune activation gene expression signature, and plasma cytokines. The neurologic assessment in neuro-oncology (NANO) scale was used to prospectively assess neurologic function.

RESULTS

Pembrolizumab alone or with bevacizumab was well tolerated but of limited benefit. For cohort A, PFS-6 was 26.0% [95% confidence interval (CI), 16.3-41.5], median overall survival (OS) was 8.8 months (95% CI, 7.7-14.2), objective response rate (ORR) was 20%, and median duration of response was 48 weeks. For cohort B, PFS-6 was 6.7% (95% CI, 1.7-25.4), median OS was 10.3 months (95% CI, 8.5-12.5), and ORR was 0%. Tumor immune markers were not associated with OS, but worsened OS correlated with baseline dexamethasone use and increased posttherapy plasma VEGF (cohort A) and mutant IDH1, unmethylated MGMT, and increased baseline PlGF and sVEGFR1 levels (cohort B). The NANO scale contributed to overall outcome assessment.

CONCLUSIONS

Pembrolizumab was ineffective as monotherapy and with bevacizumab for recurrent glioblastoma. The infrequent radiographic responses to combinatorial therapy were durable. Tumor immune biomarkers did not predict outcome. Baseline dexamethasone use and tumor MGMT warrant further study as potential biomarkers in glioblastoma immunotherapy trials.

A Window of Opportunity: Targeting Cancer Endothelium to Enhance Immunotherapy

Vascular abnormalities in tumors have a major impact on the immune microenvironment in tumors. The consequences of abnormal vasculature include increased hypoxia, acidosis, high intra-tumoral fluid pressure, and angiogenesis. This introduces an immunosuppressive microenvironment that alters immune cell maturation, activation, and trafficking, which supports tumor immune evasion and dissemination of tumor cells. Increasing data suggests that cancer endothelium is a major barrier for traveling leukocytes, ranging from a partial blockade resulting in a selective endothelial barrier, to a complete immune infiltration blockade associated with immune exclusion and immune desert cancer phenotypes. Failed immune cell trafficking as well as immunosuppression within the tumor microenvironment limits the efficacy of immunotherapeutic approaches. As such, targeting proteins with key roles in angiogenesis may potentially reduce immunosuppression and might restore infiltration of anti-tumor immune cells, creating a therapeutic window for successful immunotherapy. In this review, we provide a comprehensive overview of established as well as more controversial endothelial pathways that govern selective immune cell trafficking across cancer endothelium. Additionally, we discuss recent insights and strategies that target tumor vasculature in order to increase infiltration of cytotoxic immune cells during the therapeutic window of vascular normalization hereby improving the efficacy of immunotherapy.

Immuno-priming durvalumab with bevacizumab in HER2-negative advanced breast cancer: a pilot clinical trial

BACKGROUND

Preclinical research suggests that the efficacy of immune checkpoint inhibitors in breast cancer can be enhanced by combining them with antiangiogenics, particularly in a sequential fashion. We sought to explore the efficacy and biomarkers of combining the anti-PD-L1 durvalumab plus the antiangiogenic bevacizumab after bevacizumab monotherapy for advanced HER2-negative breast cancer.

METHODS

Patients had advanced HER2-negative disease that progressed while receiving single-agent bevacizumab maintenance as a part of a previous chemotherapy plus bevacizumab regimen. Treatment consisted of bi-weekly durvalumab plus bevacizumab (10 mg/kg each i.v.). Peripheral-blood mononuclear cells (PBMCs) were obtained before the first durvalumab dose and every 4 weeks and immunophenotyped by flow-cytometry. A fresh pre-durvalumab tumor biopsy was obtained; gene-expression studies and immunohistochemical staining to assess vascular normalization and characterize the immune infiltrate were conducted. Patients were classified as "non-progressors" if they had clinical benefit (SD/PR/CR) at 4 months. The co-primary endpoints were the changes in the percentage T cell subpopulations in PBMCs in progressors versus non-progressors, and PFS/OS time.

RESULTS

Twenty-six patients were accrued. Median PFS and OS were 3.5 and 11 months; a trend for a longer OS was detected for the hormone-positive subset (19.8 versus 7.4 months in triple-negatives; P = 0.11). Clinical benefit rate at 2 and 4 months was 60% and 44%, respectively, without significant differences between hormone-positive and triple-negative (P = 0.73). Non-progressors' tumors displayed vascular normalization features as a result of previous bevacizumab, compared with generally abnormal patterns observed in progressors. Non-progressors also showed increased T-effector and T-memory signatures and decreased TREG signatures in gene expression studies in baseline-post-bevacizumab-tumors compared with progressors. Notably, analysis of PBMC populations before durvalumab treatment was concordant with the findings in tumor samples and showed a decreased percentage of circulating TREGs in non-progressors.

CONCLUSIONS

This study reporting on sequential bevacizumab+durvalumab in breast cancer showed encouraging activity in a heavily pre-treated cohort. The correlative studies agree with the preclinical rationale supporting an immunopriming effect exerted by antiangiogenic treatment, probably by reducing TREGs cells both systemically and in tumor tissue. The magnitude of this benefit should be addressed in a randomized setting.

TRIAL REGISTRATION

(www.clinicaltrials.gov): NCT02802098 . Registered on June 16, 2020.

Neuro-ophthalmic Complications of Immune Checkpoint Inhibitors: A Systematic Review

OBJECTIVE

Immune checkpoint inhibitors (ICIs) are novel cancer therapies that may be associated with immune-related adverse events (IRAEs) and come to the attention of neuro-ophthalmologists. This systematic review aims to synthesize the reported ICI-associated IRAEs relevant to neuro-ophthalmologists to help in the diagnosis and management of these conditions.

METHODS

A systematic review of the literature indexed by MEDLINE, Embase, CENTRAL, and Web of Science databases was searched from inception to May 2020. Reporting followed the Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) guidelines. Primary studies on ICIs and neuro-ophthalmic complications were included. Outcomes included number of cases and incidence of neuro-ophthalmic IRAEs.

RESULTS

Neuro-ophthalmic complications of ICIs occurred in 0.46% of patients undergoing ICI and may affect the afferent and efferent visual systems. Afferent complications include optic neuritis (12.8%), neuroretinitis (0.9%), and giant cell arteritis (3.7%). Efferent complications include myasthenia gravis (MG) (45.0%), thyroid-like eye disease (11.9%), orbital myositis (13.8%), general myositis with ptosis (7.3%), internuclear ophthalmoplegia (0.9%), opsoclonus-myoclonus-ataxia syndrome (0.9%), and oculomotor nerve palsy (0.9%). Pembrolizumab was the most common causative agent for neuro-ophthalmic complications (32.1%). Mortality was highest for MG (19.8%). Most patients (79.8%) experienced improvement or complete resolution of neuro-ophthalmic symptoms due to cessation of ICI and immunosuppression with systemic corticosteroids.

CONCLUSION

While incidence of neuro-ophthalmic IRAEs is low, clinicians involved in the care of cancer patients must be aware of their presentation to facilitate prompt recognition and management. Collaboration between oncology and neuro-ophthalmology teams is required to effectively manage patients and reduce morbidity and mortality.

Are antiangiogenics a good 'partner' for immunotherapy in ovarian cancer?

Ovarian cancer (OC) is associated with poor survival because there are a limited number of effective therapies. Two processes key to OC progression, angiogenesis and immune evasion, act synergistically to promote tumor progression. Tumor-associated angiogenesis promotes immune evasion, and tumor-related immune responses in the peritoneal cavity and tumor microenvironment (TME) affect neovascular formation. Therefore, suppressing the angiogenic pathways could facilitate the arrival of immune effector cells and reduce the presence of myeloid cells involved in immune suppression. To date, clinical studies have shown significant benefits with antiangiogenic therapy as first-line therapy in OC, as well as in recurrent disease, and the vascular endothelial growth factor (VEGF) inhibitor bevacizumab is now an established therapy. Clinical data with immunomodulators in OC are more limited, but suggest that they could benefit some patients with recurrent disease. The preliminary results of two phase III trials have shown that the addition of immunomodulators to chemotherapy does not improve progression-free survival. For this reason, it could be interesting to look for synergistic effects between immunomodulators and other active drugs in OC. Since bevacizumab is approved for use in OC, and is tolerable when used in combination with immunotherapy in other indications, a number of clinical studies are underway to investigate the use of bevacizumab in combination with immunotherapeutic agents in OC. This strategy seeks to normalize the TME via the anti-VEGF actions of bevacizumab, while simultaneously stimulating the immune response via the immunotherapy. Results of these studies are awaited with interest.

Neoangiogenesis in Melanoma: An Issue in Biology and Systemic Treatment

Neoangiogenesis is a recognized hallmark of cancer, granting tumor cells to dispose of metabolic substrates through a newly created vascular supply. Neoangiogenesis was also confirmed in melanoma, where vascular proliferation is associated with increased aggressiveness and poorer prognosis. Furthermore, melanoma cells show the so-called vascular mimicry, consisting in the assumption of endothelial-like features inducing the expression of pro-angiogenic receptors and ligands, which take part in the interplay with extracellular matrix (ECM) components and are potentiated by the ECM remodeling and the barrier molecule junction alterations that characterize the metastatic phase. Although neoangiogenesis was biologically proven and clinically associated with worse outcomes in melanoma patients, in the past anti-angiogenic therapies were employed with poor improvement of the already unsatisfactory results associated with chemotherapic agents. Among the novel therapies of melanoma, immunotherapy has led to previously unexpected outcomes of treatment, yet there is a still strong need for potentiating the results, possibly by new regimens of combination therapies. Molecular models in many cancer types showed mutual influences between immune responses and vascular normalization. Recently, clinical trials are investigating the efficacy of the association between anti-angiogenetic agents and immune-checkpoint inhibitors to treat advanced stage melanoma. This paper reviews the biological bases of angiogenesis in melanoma and summarizes the currently available clinical data on the use of anti-angiogenetic compounds in melanoma.

Old Player-New Tricks: Non Angiogenic Effects of the VEGF/VEGFR Pathway in Cancer

Angiogenesis has long been considered to facilitate and sustain cancer growth, making the introduction of anti-angiogenic agents that disrupt the vascular endothelial growth factor/receptor (VEGF/VEGFR) pathway an important milestone at the beginning of the 21st century. Originally research on VEGF signaling focused on its survival and mitogenic effects towards endothelial cells, with moderate so far success of anti-angiogenic therapy. However, VEGF can have multiple effects on additional cell types including immune and tumor cells, by directly influencing and promoting tumor cell survival, proliferation and invasion and contributing to an immunosuppressive microenvironment. In this review, we summarize the effects of the VEGF/VEGFR pathway on non-endothelial cells and the resulting implications of anti-angiogenic agents that include direct inhibition of tumor cell growth and immunostimulatory functions. Finally, we present how previously unappreciated studies on VEGF biology, that have demonstrated immunomodulatory properties and tumor regression by disrupting the VEGF/VEGFR pathway, now provide the scientific basis for new combinational treatments of immunotherapy with anti-angiogenic agents.

Immune Checkpoint Therapies for Melanoma

Immunotherapy with immune checkpoint inhibition has dramatically changed the treatment of melanoma. Immune checkpoint inhibitors targeting cytotoxic T-lymphocyte-associated protein 4 and programmed cell death protein 1 are approved for the treatment of advanced melanoma alone and in combination. In addition, these agents are approved for use in high-risk resected stage III melanoma in the adjuvant setting. Clinical trials testing the combination of immune checkpoint inhibition with other therapies and novel immunotherapies continue. This article reviews the current literature on approved uses of immune checkpoint inhibition in melanoma and discusses ongoing trials and future directions.

sFRP2 Supersedes VEGF as an Age-related Driver of Angiogenesis in Melanoma, Affecting Response to Anti-VEGF Therapy in Older Patients

PURPOSE

Angiogenesis is thought to be critical for tumor metastasis. However, inhibiting angiogenesis using antibodies such as bevacizumab (Avastin), has had little impact on melanoma patient survival. We have demonstrated that both angiogenesis and metastasis are increased in older individuals, and therefore sought to investigate whether there was an age-related difference in response to bevacizumab, and if so, what the underlying mechanism could be.

EXPERIMENTAL DESIGN

We analyzed data from the AVAST-M trial of 1,343 patients with melanoma treated with bevacizumab to determine whether there is an age-dependent response to bevacizumab. We also examined the age-dependent expression of VEGF and its cognate receptors in patients with melanoma, while using syngeneic melanoma animal models to target VEGF in young versus old mice. We also examined the age-related proangiogenic factor secreted frizzled-related protein 2 (sFRP2) and whether it could modulate response to anti-VEGF therapy.

RESULTS

We show that older patients respond poorly to bevacizumab, whereas younger patients show improvement in both disease-free survival and overall survival. We find that targeting VEGF does not ablate angiogenesis in an aged mouse model, while sFRP2 promotes angiogenesis in vitro and in young mice. Targeting sFRP2 in aged mice successfully ablates angiogenesis, while the effects of targeting VEGF in young mice can be overcome by increasing sFRP2.

CONCLUSIONS

VEGF is decreased during aging, thereby reducing response to bevacizumab. Despite the decrease in VEGF, angiogenesis is increased because of an increase in sFRP2 in the aged tumor microenvironment. These results stress the importance of considering age as a factor for designing targeted therapies.

Managing Ipilimumab-Induced Hypophysitis: Challenges and Current Therapeutic Strategies

Over the past years, progress has been made in cancer immunotherapy following the development of immune checkpoint inhibitors (ICI) that have been proved effective in the management of many malignancies. Ipilimumab, a monoclonal antibody against cytotoxic T-lymphocyte antigen-4 (CTLA-4), has been approved for the treatment of advanced melanoma but has been associated with the development of several endocrine immune-related adverse events (irAEs). Hypophysitis is the most common endocrine irAE related to ipilimumab with a reported incidence ranging from 1.8% to 17%. The mechanism underlying ipilimumab-induced hypophysitis implicates immune, inflammatory and genetic factors, but there are still some points that are not well understood and remain to be elucidated. The diagnosis is based mainly on clinical, biochemical and imaging data. The majority of patients display multiple hormone deficiencies that may recover or persist for a prolonged period of time with corticotroph deficiency usually being permanent. Immune-related hypopituitarism is treated with replacement of deficient hormones while in severe forms of hypophysitis treatment with high-dose glucocorticoids may be required. Proper evaluation and registration of patients in clinical trials and further investigation are needed to precisely clarify the pathophysiology of the ICI-related hypophysitis, define predictive factors and ameliorate the management and outcome of the disease.

Phase II study of atezolizumab in combination with bevacizumab in patients with advanced cervical cancer

Background

There are limited treatment options for patients with metastatic or recurrent cervical cancer. Platinum-based chemotherapy plus the anti-vascular endothelial growth factor antibody bevacizumab remains the mainstay of advanced treatment. Pembrolizumab is Food and Drug Agency approved for programmed death ligand 1 (PD-L1) positive cervical cancer with a modest response rate. This is the first study to report the efficacy and safety of the PD-L1 antibody atezolizumab in combination with bevacizumab in advanced cervical cancer.

Methods

We report the results from a phase II, open-label, multicenter study (NCT02921269). Patients with advanced cervical cancer were treated with bevacizumab 15 mg/kg intravenous every 3 weeks and atezolizumab 1200 mg intravenous every 3 weeks. The primary objective was to measure the objective response rate (ORR). Secondary endpoints included disease control rate (DCR), progression-free survival (PFS), overall survival (OS), and safety.

Results

In the total evaluable population (n=10), zero patients achieved an objective response as assessed by Response Evaluation Criteria In Solid Tumors (RECIST) V.1.1, resulting in a confirmed ORR of 0%. Of note, there were two patients who achieved an unconfirmed PR. The DCR by RECIST V.1.1 was 60% (0% complete response, 0% partial response, 60% stable disease). Median PFS was 2.9 months (95% CI, 1.8 to 6) and median OS was 8.9 months (95% CI, 3.4 to 21.9). Safety results were generally consistent with the known safety profile of both drugs, notably with two high-grade neurologic events.

Conclusions

The combination of bevacizumab and atezolizumab did not meet the predefined efficacy endpoint, as addition of bevacizumab to PD-L1 blockade did not appear to enhance the ORR in cervical cancer.

Beyond Antoni: A Surgeon's Guide to the Vestibular Schwannoma Microenvironment

Introduction Vestibular schwannomas (VS) are histologically benign tumors arising from cranial nerve VIII. Far from a homogenous proliferation of Schwann cells, mounting evidence has highlighted the complex nature of the inflammatory microenvironment in these tumors.

Methods A review of the literature pertaining to inflammation, inflammatory molecular pathways, and immune-related therapeutic targets in VS was performed. Relevant studies published up to June 2020 were identified based on a literature search in the PubMed and MEDLINE databases and the findings were synthesized into a concise narrative review of the topic.

Results The VS microenvironment is characterized by a dense infiltrate of inflammatory cells, particularly macrophages. Significantly higher levels of immune cell infiltration are observed in growing versus static tumors, and there is a demonstrable interplay between inflammation and angiogenesis in growing VS. While further mechanistic studies are required to ascertain the exact role of inflammation in angiogenesis, tumor growth, and Schwann cell control, we are beginning to understand the key molecular pathways driving this inflammatory microenvironment, and how these processes can be monitored and targeted in vivo.

Conclusion Observational research has revealed a complex and heterogeneous tumor microenvironment in VS. The functional landscape and roles of macrophages and other immune cells in the VS inflammatory infiltrate are, however, yet to be established. The antiangiogenic drug bevacizumab has shown the efficacy of targeted molecular therapies in VS and there is hope that agents targeting another major component of the VS microenvironment, inflammation, will also find a place in their future management.

Anti-PD-1/L1 plus anti-angiogenesis therapy as second-line or later treatment in advanced lung adenocarcinoma

PURPOSE

Anti-programmed cell death protein 1 or its ligand (anti-PD-1/L1) monotherapy has become the standard second-line treatment in advanced lung adenocarcinoma. However, the strategy treatment of anti-PD-1/L1 plus anti-angiogenesis therapy has not been evaluated. We conducted this retrospective study to assess the efficacy and safety of anti-PD-1/L1 plus anti-angiogenesis therapy in patients with advanced lung adenocarcinoma in the second-line or later setting.

METHODS

Patients with advanced lung adenocarcinoma who received anti-PD-1/L1 plus anti-angiogenesis therapy or anti-PD-1/L1 monotherapy in the second-line or later treatment from March 2015 to May 2019 in PLA General Hospital were retrospectively analyzed. The progression-free survival (PFS), overall survival (OS), objective response rate (ORR), disease control rate (DCR), and safety were assessed. Multivariate analyses of PFS and OS were performed with Cox proportional hazard regression models.

RESULTS

Seventy-four patients were included in our study. Twenty-five patients were treated with anti-PD-1/L1 plus anti-angiogenesis therapy, and forty-nine patients were treated with anti-PD-1/L1 monotherapy. The disease control rate (DCR) was higher in the anti-PD-1/L1 plus anti-angiogenesis group than in the anti-PD-1/L1 monotherapy group (92.0% vs. 46.9%, P = 0.0004). The median progression-free survival (PFS) was 5.1 months vs. 2.0 months (HR 0.551 [95% confidence interval 0.337-0.902], P = 0.002) and median overall survival (OS) was 14.3 months vs. 8.4 months (HR 0.549 [95% CI 0.305-0.990], P = 0.046), respectively. Multivariate Cox proportional hazard regression models showed that anti-PD-1/L1 plus anti-angiogenesis group had prolonged PFS (HR 0.541 [95% CI 0.298-0.981], P = 0.033). The incidences of grade 3/4 adverse events were 12% (3/25) in anti-PD-1/L1 plus anti-angiogenesis group and 6% (3/49) in anti-PD-1/L1 monotherapy group.

CONCLUSION

Compared with anti-PD-1/L1 monotherapy, anti-PD-1/L1 plus anti-angiogenesis therapy could significantly improve the clinical response and bring longer PFS and OS in patients with advanced lung adenocarcinoma who had failed first-line or later treatment. Further prospective studies are needed to validate our findings.

Targeted and immunotherapies in BRAF mutant melanoma: where we stand and what to expect

The therapeutic landscape for melanoma has evolved drastically in the past decade. Currently, immune checkpoint inhibitors and small-molecule inhibitors targeting the mitogen-activated protein kinase (MAPK) pathway are the two mainstay therapies for BRAF^V600 mutant advanced melanoma. Although MAPK dependence has been variably demonstrated in melanomas lacking BRAF^V600 mutations, definitive evidence of benefit with MAPK inhibitors has not been demonstrated. Thus, in the BRAF^V600 'wild-type' setting, immune checkpoint inhibitors are the standalone option(s). In the BRAF^V600 mutant setting, there is no definitive evidence prioritizing one therapeutic modality over another. Herein, we review the updated data of the pivotal phase III randomized controlled trials that established the standard-of-care first-line treatment for advanced melanoma, as it provides insights into long-term benefit, which is a major factor in therapy selection. We discuss the clinical considerations for choosing between these therapies in the front-line setting and beyond, specifically for patients with BRAF^V600 mutant melanoma based on currently available evidence. We have previously proposed a time-dependent resistance paradigm in which future therapeutic development strategies can be rooted. We also discuss how these Food and Drug Administration (FDA)-approved therapeutic modalities are being pursued earlier in the course of disease management, namely in adjuvant and neoadjuvant settings. FDA-approved interlesional oncolytic virotherapy in the modern era is also briefly discussed.

Anti-PD-1 antibody SHR-1210 plus apatinib for metastatic colorectal cancer: a prospective, single-arm, open-label, phase II trial

In the REGONIVO study, regorafenib combined with nivolumab was effective in the treatment of microsatellite stable (MSS) metastatic colorectal cancer (mCRC), which indicated anti-angiogenic drugs may enhance the efficacy of immune checkpoint inhibitors. Therefore, we designed a single-arm, single-center, open-label, phase II trial to determine the toxicity and efficacy of SHR-1210 (an anti-PD-1 antibody) plus apatinib in MSS mCRC. The sample size was estimated using a Simon Optimum two-stage design. 10 patients were included at the first stage and if one effective patient observed, an additional 19 patients would be added. Patients with MSS mCRC who refractory to second-line treatment or intolerant to standard treatment were given SHR-1210 200 mg every 2 weeks and apatinib 250-375 mg once daily until unacceptable toxicity or disease progression occurred. In our study, the objective response rate was 0% and the disease control rate was 22.2%. The median progression-free survival was 1.83 months (95% confidence interval (CI) 1.80-1.86 months), and the median overall survival was 7.80 months (95% CI 0-17.07). Treatment-related adverse events (AEs) occurred in all patients (100%). The most common treatment-related AEs were hypertension and proteinuria (70% each). Grade 3 AEs were observed in nine patients (9/10, 90%), and the commonest was hypertension (30%). In conclusion, SHR-1210 combined with apatinib has failed to improve the efficacy of treatment of MSS mCRC, and the intolerable toxicity may be the leading cause.

Phase II study on first-line treatment of NIVolumab in combination with folfoxiri/bevacizumab in patients with Advanced COloRectal cancer RAS or BRAF mutated - NIVACOR trial (GOIRC-03-2018)

Background

FOLFOXIRI (fluorouracil, leucovorin, oxaliplatin, and irinotecan) plus bevacizumab has shown to be one of the therapeutic regimens in first line with the highest activity in patients (pts.) with metastatic colorectal cancer (mCRC) unselected for biomolecular alterations. Generally, tumors co-opt the programmed death-1/ligand 1 (PD-1/PD-L1) signaling pathway as one key mechanism to evade immune surveillance. As today, anti-PD-1 monoclonal antibodies are FDA approved only for DNA mismatch repair deficient/microsatellite instability-high (MMRd/MSI-H), which represent only about 5% among all mCRC. Nowadays, there are no data demonstrating anti PD-1 activity in proficient and stable disease (MMRp/MSS). A different target in mCRC is also the Vascular Endothelial Growth Factor A (VEGF-A), which acts on endothelial cells to stimulate angiogenesis. VEGF-A inhibition with bevacizumab has shown to increase the immune cell infiltration, providing a solid rationale for combining VEGF targeted agents with immune checkpoint inhibitors. Based on these evidences, we explore the combination of triplet chemotherapy (FOLFOXIRI) with bevacizumab and nivolumab in pts. with mCRC RAS/BRAF mutant regardless of microsatellite status.

Methods/design

This is a prospective, open-label, multicentric phase II trial where pts. with mCRC RAS/BRAF mutated, in first line will receive nivolumab in combination with FOLFOXIRI/bevacizumab every 2 weeks for 8 cycles followed by maintenance with bevacizumab plus nivolumab every 2 weeks. Bevacizumab will be administered intravenously at dose of 5 mg/kg every 2 weeks and nivolumab intravenously as a flat dose of 240 mg every 2 weeks. The primary endpoint is the overall response rate (ORR). This study hypothesis is that the treatment is able to improve the ORR from 66 to 80%. Secondary endpoints include OS, safety, time to progression, duration of response. Collateral translational studies evaluate the i) tumor mutational burden, and ii) genetic alterations by circulating free DNA (cfDNA) obtained from plasma samples. The trial is open to enrollment, 9 of planned 70 pts. have been enrolled.

Trial registration

NIVACOR is registered at ClinicalTrials.gov: NCT04072198, August 28, 2019.

Resisting Resistance to Immune Checkpoint Therapy: A Systematic Review

The treatment landscape in oncology has witnessed a major revolution with the introduction of checkpoint inhibitors: anti-PD1, anti-PDL1 and anti-CTLA-4. These agents enhance the immune response towards cancer cells instead of targeting the tumor itself, contrary to standard chemotherapy. Although long-lasting durable responses have been observed with immune checkpoints inhibitors, the response rate remains relatively low in many cases. Some patients respond in the beginning but then eventually develop acquired resistance to treatment and progress. Other patients having primary resistance never respond. Multiple studies have been conducted to further elucidate these variations in response in different tumor types and different individuals. This paper provides an overview of the mechanisms of resistance to immune checkpoint inhibitors and highlights the possible therapeutic approaches under investigation aiming to overcome such resistance in order to improve the clinical outcomes of cancer patients.

Anti-angiogenic Agents in Combination With Immune Checkpoint Inhibitors: A Promising Strategy for Cancer Treatment

Advances in cancer immunity have promoted a major breakthrough in the field of cancer therapy. This is mainly associated with the successful development of immune checkpoint inhibitors (ICIs) for multiple types of human tumors. Blockade with different ICIs, including programmed cell death 1 (PD-1), programmed cell death-ligand 1 (PD-L1), and cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) inhibitors, may activate the immune system of the host against malignant cells. However, only a subgroup of patients with cancer would benefit from immune checkpoint blockade. Some patients experience primary resistance to initial immunotherapy, and a majority eventually develop acquired resistance to ICIs. However, the mechanisms involved in the development of drug resistance to immune checkpoint blockade remain unclear. Recent studies supported that combination of ICIs and anti-angiogenic agents could be a promising therapeutic strategy for overcoming the low efficacy of ICIs. Moreover, through their direct anti-cancer effect by inhibiting tumor growth and metastasis, anti-angiogenic drugs reprogram the tumor milieu from an immunosuppressive to an immune permissive microenvironment. Activated immunity by immune checkpoint blockade also facilitates anti-angiogenesis by downregulating the expression of vascular endothelial growth factor and alleviating hypoxia condition. Many clinical trials showed an improved anti-cancer efficacy and prolonged survival following the addition of anti-angiogenic agents to ICIs. This review summarizes the current understanding and clinical development of combination therapy with immune checkpoint blockade and anti-angiogenic strategy.

Tumor Endothelial Cells (TECs) as Potential Immune Directors of the Tumor Microenvironment - New Findings and Future Perspectives

The tumor microenvironment (TME) plays a central role in cancer development and progression. It represents a complex network of cancer cell (sub-)clones and a variety of stromal cell types. Recently, new technology platforms shed light on the cellular composition of the TME at very high resolution and identified a complex landscape of multi-lineage immune cells (e.g., T and B lymphocytes, myeloid cells, and dendritic cells), cancer associated fibroblasts (CAF) and tumor endothelial cells (TECs). A growing body of evidence suggests that metabolically, genetically and on their transcriptomic profile TECs exhibit unique phenotypic and functional characteristics when compared to normal endothelial cells (NECs). Furthermore, the functional role of TECs is multifaceted as they are not only relevant for promoting tumor angiogenesis but have also evolved as key mediators of immune regulation in the TME. Regulatory mechanisms are complex and profoundly impact peripheral immune cell trafficking into the tumor compartment by acting as major gatekeepers of cellular transmigration. Moreover, TECs are associated with T cell priming, activation and proliferation by acting as antigen-presenting cells themselves. TECs are also essential for the formation of tertiary lymphoid structures (TLS) within the tumor, which have recently been associated with treatment response to checkpoint antibody therapy. Further essential characteristics of TECs compared to NECs are their high proliferative potential as well as greatly altered gene expression profile (e.g., upregulation of pro-angiogenic, extracellular matrix remodeling, and stemness genes), which results in enhanced secretion of immunomodulatory cytokines and altered cell-surface receptors [e.g., major histocompatibility complex (MHC) and immune checkpoints]. The TEC phenotype may be rooted in an aggressive tumor micro-milieu based on cellular stress via hypoxia and reactive oxygen species (ROS). Vice versa TECs might modulate TME immunogenicity thereby fostering cancer-associated immune suppression. This review aims to elucidate the currently emergent pathophysiological aspects of TECs with a particular focus on their potential role as regulators of immune cell function in the TME. It is a main future challenge to deeply characterize the phenotypic and functional profile of TECs to illuminate their complex role within the TME. The ultimate goal is the identification of TEC-specific drug targets to improve cancer (immuno-)therapy.