Cytokine levels correlate with immune cell infiltration after anti-VEGF therapy in preclinical mouse models of breast cancer

Comprehensive analyses of PBRM1 in multiple cancer types and its association with clinical response to immunotherapy and immune infiltrates

Background

The prognostic value of polybromo 1 (PBRM1) gene mutations in clear cell renal carcinoma (CCRCC) with anti-programmed death-ligand 1 (PD-L1) therapy remains controversial, and few studies have reported the impact of PBRM1 mutations in other cancer types.

Methods

The patient information was obtained from cBioPortal and the Tumor Immune Estimation Resource (TIMER) databases. Mann-Whitney U test were used for correlation analysis. For survival analyses, Kaplan-Meier survival curves were used and compared using the log-rank test. Cox’s regression model was used to perform univariable and multivariable analyses

Results

Our study, for the first time, performed comprehensive analyses of PBRM1 mutation frequency, PBRM1 expression, relationship of PBRM1 mutations with clinical benefit from immunotherapy, and PBRM1 expression with immune infiltrates in diverse cancer types. The results showed that the expression of PBRM1 was significantly lower in diverse cancer types compared with normal tissues. Based on multivariable analysis, PBRM1 mutations trended towards worse clinical outcomes from anti-PD-L1 in CCRCC, lung adenocarcinoma (LUAD), bladder urothelial carcinoma (BLCA), and skin cutaneous melanoma (SKCM), and a significant association was observed in LUAD and BLCA. PBRM1 mutations were associated with higher TMB in diverse cancer types and significant associations were observed in LUAD and BLCA. The expression of PBRM1 was found to positively correlate with immune infiltrates in diverse cancer types.

Conclusions

Our findings suggested caution in starting immunotherapy alone in PBRM1 mutant patients. Further studies are needed to improve treatment for PBRM1 mutant patients.

A High-Dimensional Window into the Micro-Environment of Triple Negative Breast Cancer

Providing effective personalized immunotherapy for triple negative breast cancer (TNBC) patients requires a detailed understanding of the composition of the tumor microenvironment. Both the tumor cell and non-tumor components of TNBC can exhibit tremendous heterogeneity in individual patients and change over time. Delineating cellular phenotypes and spatial topographies associated with distinct immunological states and the impact of chemotherapy will be necessary to optimally time immunotherapy. The clinical successes in immunotherapy have intensified research on the tumor microenvironment, aided by a plethora of high-dimensional technologies to define cellular phenotypes. These high-dimensional technologies include, but are not limited to, single cell RNA sequencing, spatial transcriptomics, T cell repertoire analyses, advanced flow cytometry, imaging mass cytometry, and their integration. In this review, we discuss the cellular phenotypes and spatial patterns of the lymphoid-, myeloid-, and stromal cells in the TNBC microenvironment and the potential value of mapping these features onto tumor cell genotypes.

Current status of immunotherapy for advanced gastric cancer

Recently, immune checkpoint inhibitors such as anti-programmed cell death-1 (PD-1) or programmed cell death ligand-1 (PD-L1) monoclonal antibodies have improved the overall survival of various types of cancers including advanced gastric cancer (AGC). Until now, two ant-PD-1 inhibitors were approved for AGC in Japan: nivolumab as third- or later-line treatment for AGC and pembrolizumab for previously treated patients with microsatellite instability-high tumours. However, a limited number of patients achieved clinical benefit, highlighting the importance of the better selection of patients or additional treatment to overcome resistance to PD-1/PD-L1 blockade. This review focused on pivotal clinical trials, biomarkers and novel combination therapy of immune checkpoint inhibitors forAGC.

Structure-based Development of Human Interleukin-1β-Specific Antibody That Simultaneously Inhibits Binding to Both IL-1RI and IL-1RAcP

Interleukin-1β (IL-1β) is a potent pleiotropic cytokine playing a central role in protecting cells from microbial pathogen infection or endogenous stress. After it binds to IL-1RI and recruits IL-1 receptor accessory protein (IL-1RAcP), signaling culminates in activation of NF-κB. Many pathophysiological diseases have been attributed to the derailment of IL-1β regulation. Several blocking reagents have been developed based on two mechanisms: blocking the binding of IL-1β to IL-1RI or inhibiting the recruitment of IL-1RAcP to the IL-1β initial complex. In order to simultaneously fulfill these two actions, a human anti-IL-1β neutralizing antibody IgG26 was screened from human genetic phage-display library and furthered structure-optimized to final version, IgG26AW. IgG26AW has a sub-nanomolar binding affinity for human IL-1β. We validated IgG26AW-neutralizing antibodies specific for IL-1β in vivo to prevent human IL-1β-driving IL-6 elevation in C56BL/6 mice. Mice underwent treatments with IgG26AW in A549 and MDA-MB-231 xenograft mouse cancer models have also been observed with tumor shrank and inhibition of tumor metastasis. The region where IgG26 binds to IL-1β also overlaps with the position where IL-1RI and IL-1RAcP bind, as revealed by the 26-Fab/IL-1β complex structure. Meanwhile, SPR experiments showed that IL-1β bound by IgG26AW prevented the further binding of IL-1RI and IL-1RAcP, which confirmed our inference from the result of protein structure. Therefore, the inhibitory mechanism of IgG26AW is to block the assembly of the IL-1β/IL-1RI/IL-1RAcP ternary complex which further inhibits downstream signaling. Based on its high affinity, high neutralizing potency, and novel binding epitope simultaneously occupying both IL-1RI and IL-1RAcP residues that bind to IL-1β, IgG26AW may be a new candidate for treatments of inflammation-related diseases or for complementary treatments of cancers in which the role of IL-1β is critical to pathogenesis.

PD1/PD-L1 therapy in metastatic renal cell carcinoma

PURPOSE OF REVIEW

The aim of the article to summarize recent changes of treatment options in metastatic renal cell carcinoma (mRCC) with a special emphasis on immune checkpoint inhibition.

RECENT FINDINGS

The introduction of checkpoint inhibitor (CPI) therapy has led to a paradigm change in advanced renal cell carcinoma (RCC). Dual immune checkpoint inhibition or the combination of CPI and tyrosine kinase inhibitors (TKIs) was shown to improve survival when compared with the former standard of care sunitinib. Moreover, these novel strategies were shown to enable unprecedented rates of complete and durable responses, particularly with dual checkpoint inhibition. Although the treatment landscape has rapidly evolved, it remains unknown which combination is the best for the individual patient. Pivotal trials have used sunitinib as a comparator but no head to head comparisons have been conducted between novel agents so far. Moreover, no predictive biomarker has been identified yet to bring the best treatment to the individual patient.

SUMMARY

The aim of this review is to summarize the findings of CPI-based trials conducted in RCC and to discuss the future of mRCC treatment.

Immuno-oncology for Hepatocellular Carcinoma: The Present and the Future

Hepatocellular carcinoma is a highly prevalent and lethal cancer that many therapeutics are being tested for this disease. It has the potential to be a highly immune-responsive tumor given its inflammatory origins. The first immunotherapies were anti-programmed death-1 monotherapies, which improved response rates and survival. Novel immunotherapy combinations and immunotherapy show promise in frontline treatment. The novel antibody therapy combination of atezolizumab and bevacizumab may be practice changing. Although these landmark studies seem to offer new treatment options, the role of immunotherapy in the liver transplant setting is uncertain until the safety of this approach is defined.

Current Translational and Clinical Challenges in Advanced Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is a frequent and increasing cause of cancerrelated deaths worldwide. Reversing this trend is complicated by the varied aetiological factors leading to liver cirrhosis resulting in molecular genetic and clinical heterogeneity, combined with frequent presentation at advanced stage. Large-scale genomic studies have identified alterations in key signalling pathways for HCC development and progression, but these findings have not yet directly influenced patient management in the clinical setting. Despite these translational challenges, a small number of anti-angiogenic systemic therapy agents have succeeded in recent randomized trials enriching the repertoire of available treatments for advanced HCC. In addition, the early promise of immune checkpoint inhibition is now on the cusp of delivering changes to standard systemic therapy algorithms. This review focuses on recent translational and clinical developments that have advanced. current practice and explores the challenges encountered in attempting to improve the outcomes and experience of patients diagnosed with advanced HCC.

Avelumab plus axitinib versus sunitinib in advanced renal cell carcinoma: biomarker analysis of the phase 3 JAVELIN Renal 101 trial

We report on molecular analyses of baseline tumor samples from the phase 3 JAVELIN Renal 101 trial (n = 886; NCT02684006 ), which demonstrated significantly prolonged progression-free survival (PFS) with first-line avelumab + axitinib versus sunitinib in advanced renal cell carcinoma (aRCC). We found that neither expression of the commonly assessed biomarker programmed cell death ligand 1 (PD-L1) nor tumor mutational burden differentiated PFS in either study arm. Similarly, the presence of FcɣR single nucleotide polymorphisms was unimpactful. We identified important biological features associated with differential PFS between the treatment arms, including new immunomodulatory and angiogenesis gene expression signatures (GESs), previously undescribed mutational profiles and their corresponding GESs, and several HLA types. These findings provide insight into the determinants of response to combined PD-1/PD-L1 and angiogenic pathway inhibition and may aid in the development of strategies for improved patient care in aRCC.

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.

Pancreatic cancer stroma: an update on therapeutic targeting strategies

Pancreatic ductal adenocarcinoma (PDAC) is a leading cause of cancer-related mortality in the Western world with limited therapeutic options and dismal long-term survival. The neoplastic epithelium exists within a dense stroma, which is recognized as a critical mediator of disease progression through direct effects on cancer cells and indirect effects on the tumour immune microenvironment. The three dominant entities in the PDAC stroma are extracellular matrix (ECM), vasculature and cancer-associated fibroblasts (CAFs). The ECM can function as a barrier to effective drug delivery to PDAC cancer cells, and a multitude of strategies to target the ECM have been attempted in the past decade. The tumour vasculature is a complex system and, although multiple anti-angiogenesis agents have already failed late-stage clinical trials in PDAC, other vasculature-targeting approaches aimed at vessel normalization and tumour immunosensitization have shown promise in preclinical models. Lastly, PDAC CAFs participate in active cross-talk with cancer cells within the tumour microenvironment. The existence of intratumoural CAF heterogeneity represents a paradigm shift in PDAC CAF biology, with myofibroblastic and inflammatory CAF subtypes that likely make distinct contributions to PDAC progression. In this Review, we discuss our current understanding of the three principal constituents of PDAC stroma, their effect on the prevalent immune landscape and promising therapeutic targets within this compartment.

The New Era of Cancer Immunotherapy: Targeting Myeloid-Derived Suppressor Cells to Overcome Immune Evasion

Suppression of antitumor immune responses is one of the main mechanisms by which tumor cells escape from destruction by the immune system. Myeloid-derived suppressor cells (MDSCs) represent the main immunosuppressive cells present in the tumor microenvironment (TME) that sustain cancer progression. MDSCs are a heterogeneous group of immature myeloid cells with a potent activity against T-cell. Studies in mice have demonstrated that MDSCs accumulate in several types of cancer where they promote invasion, angiogenesis, and metastasis formation and inhibit antitumor immunity. In addition, different clinical studies have shown that MDSCs levels in the peripheral blood of cancer patients correlates with tumor burden, stage and with poor prognosis in multiple malignancies. Thus, MDSCs are the major obstacle to many cancer immunotherapies and their targeting may be a beneficial strategy for improvement the efficiency of immunotherapeutic interventions. However, the great heterogeneity of these cells makes their identification in human cancer very challenging. Since both the phenotype and mechanisms of action of MDSCs appear to be tumor-dependent, it is important to accurately characterized the precise MDSC subsets that have clinical relevance in each tumor environment to more efficiently target them. In this review we summarize the phenotype and the suppressive mechanisms of MDSCs populations expanded within different tumor contexts. Further, we discuss about their clinical relevance for cancer diagnosis and therapy.

Role of Tumor-Associated Myeloid Cells in Breast Cancer

Stromal immune cells constitute the tumor microenvironment. These immune cell subsets include myeloid cells, the so-called tumor-associated myeloid cells (TAMCs), which are of two types: tumor-associated macrophages (TAMs) and myeloid-derived suppressor cells (MDSCs). Breast tumors, particularly those in human epidermal growth factor receptor 2 (HER-2)-positive breast cancer and triple-negative breast cancer, are solid tumors containing immune cell stroma. TAMCs drive breast cancer progression via immune mediated, nonimmune-mediated, and metabolic interactions, thus serving as a potential therapeutic target for breast cancer. TAMC-associated breast cancer treatment approaches potentially involve the inhibition of TAM recruitment, modulation of TAM polarization/differentiation, reduction of TAM products, elimination of MDSCs, and reduction of MDSC products. Furthermore, TAMCs can enhance or restore immune responses during cancer immunotherapy. This review describes the role of TAMs and MDSCs in breast cancer and elucidates the clinical implications of TAMs and MDSCs as potential targets for breast cancer treatment.

AtezoTRIBE: a randomised phase II study of FOLFOXIRI plus bevacizumab alone or in combination with atezolizumab as initial therapy for patients with unresectable metastatic colorectal cancer

Background

Immune checkpoint inhibitors (ICIs) reported remarkable achievements in several solid tumours. However, in metastatic colorectal cancer (mCRC) promising results are limited to patients with deficient mismatch repair/microsatellite instability-high (dMMR/MSI-high) tumours due to their immune-enriched microenvironment. Combining cytotoxic agents and bevacizumab in mCRC with proficient mismatch repair/microsatellite stability (pMMR/MSS) could make ICIs efficacious by increasing the exposure of neoantigens, especially with highly active chemotherapy regimens, inducing immunogenic cell death, increasing the tumoral infiltration of CD8+ T-cells and reducing tumour-associated myeloid-derived suppressor cells. VEGF-blockade also plays an immunomodulatory role by inhibiting the expansion of T regulatory lymphocytes.

Consistently with this rationale, a phase Ib study combined the anti-PDL-1 atezolizumab with FOLFOX/bevacizumab as first-line treatment of mCRC, irrespective of microsatellite status, and reported interesting activity and efficacy results, without safety concerns.

Phase III trials led to identify FOLFOXIRI plus bevacizumab as an upfront therapeutic option in selected mCRC patients. Drawing from these considerations, the combination of atezolizumab with an intensified upfront treatment (FOLFOXIRI) and bevacizumab could be worthy of investigation.

Methods

AtezoTRIBE is a prospective, open label, phase II, comparative trial in which initially unresectable and previously untreated mCRC patients, irrespective of microsatellite status, are randomized in a 1:2 ratio to receive up to 8 cycles of FOLFOXIRI/bevacizumab alone or in combination with atezolizumab, followed by maintenance with bevacizumab plus 5-fluoruracil/leucovorin with or without atezolizumab according to treatment arm until disease progression. The primary endpoint is PFS. Assuming a median PFS of 12 months for standard arm, 201 patients should be randomized in a 1:2 ratio to detect a hazard ratio of 0.66 in favour of the experimental arm. A safety run-in phase including the first 6 patients enrolled in the FOLFOXIRI/bevacizumab/atezolizumab arm was planned, and no unexpected adverse events or severe toxicities were highlighted by the Safety Monitoring Committee.

Discussion

The AtezoTRIBE study aims at assessing whether the addition of atezolizumab to an intensified chemotherapy plus bevacizumab might be an efficacious upfront strategy for the treatment of mCRC, irrespective of the microsatellite status.

Trial registration

AtezoTRIBE is registered at Clinicaltrials.gov (NCT03721653), October 26th, 2018 and at EUDRACT (2017–000977-35), Februray 28th, 2017.

Good and sustained response to pembrolizumab and pazopanib in advanced undifferentiated pleomorphic sarcoma: a case report

Background

Conventional cytotoxic agents and pazopanib are approved for advanced soft tissue sarcomas but have low response rates and modest survival benefits. Recently, immune checkpoint inhibitors have shown clinically meaningful activity. The combination of pazopanib and immunotherapy has shown synergism in various other malignancies but has not been fully explored in advanced soft tissue sarcomas.

Case presentation

A 63 year old woman with metastatic undifferentiated pleomorphic sarcoma progressed after two lines of palliative combination chemotherapy—doxorubicin with olaratumab, and gemcitabine with docetaxel. In view of significant symptoms, she was treated with pazopanib in combination with pembrolizumab. She had remarkable radiological and clinical improvement, with a manageable toxicity profile and an ongoing response at ten months of therapy.

Conclusions

Undifferentiated pleomorphic sarcoma is an immunologically active subtype of soft tissue sarcoma, which is particularly amenable to immune checkpoint inhibitors. Pazopanib with immune checkpoint inhibitors is a well-tolerated, yet hitherto underexplored combination that may offer significant clinical benefit in advanced sarcomas—this finding warrants further evaluation in clinical trials.

Five-year safety and efficacy data from a phase Ib study of nivolumab and chemotherapy in advanced non-small-cell lung cancer

Combination antiprogrammed death 1/programmed death‐ligand 1 Ab and platinum‐based chemotherapy is standard first‐line treatment for advanced non‐small‐cell lung cancer without targetable oncogene alterations. We describe the long‐term safety and efficacy data from a previously reported phase Ib study of nivolumab and chemotherapy. Japanese patients with non‐small‐cell lung cancer were assigned to a treatment arm based on histology and treatment history. Nivolumab (10 mg/kg, i.v.) and chemotherapy (4 arms) were given every 3 weeks: arm A, 4 cycles of cisplatin and gemcitabine (first‐line); arm B, 4 cycles of cisplatin and pemetrexed followed by pemetrexed maintenance therapy (first‐line); arm C, 4‐6 cycles of carboplatin, paclitaxel, and bevacizumab followed by bevacizumab (first‐line); and arm D, docetaxel (second‐ or third‐line). Study treatments were continued every 3 weeks as maintenance therapy until disease progression. Minimum follow‐up period was 57.9 months. Median progression‐free survival (median [range, plus sign indicates censored data]) was 6.3 (0.7+‐47.8), 11.8 (1.4‐65.1+), 40.7 (5.3‐60.8+), and 3.2 (1.9‐10.9) months, and 5‐year progression‐free survival was observed in 0/6, 1/6, 1/6, and 0/6 patients in arms A, B, C, and D, respectively. Median overall survival was 13.2 (11.0‐55.4), 28.5 (14.6‐66.2+), not reached (24.2‐67.4+), and 12.5 (9.8‐16.9) months; the number of patients surviving 5 years were 0/6, 1/6, 4/6, and 0/6 in arms A, B, C, and D, respectively. No unexpected severe adverse events or treatment‐related deaths occurred. Nivolumab and platinum‐based chemotherapy combinations showed long‐term tolerability. A moderate proportion of patients in arm C showed 5‐year progression‐free and overall survival.

Virotherapy: From single agents to combinatorial treatments

Virotherpay is emerging as a promising strategy against cancer, and three oncolytic viruses (OVs) have gained approval in different countries for the treatment of several cancer types. Beyond the capability to selectively infect, replicate and lyse cancer cells, OVs act through a multitude of events, including modification of the tumour micro/macro-environment as well as a complex modulation of the anti-tumour immune response by activation of danger signals and immunogenic cell death pathways. Most OVs show limited effects, depending on the viral platform and the interactions with the host. OVs used as monotherapy only in a minority of patients elicited a full response. Better outcomes were obtained using OVs in combination with other treatments, such as immune therapy or chemotherapy, suggesting that the full potential of OVs can be unleashed in combination with other treatment modalities. Here, we report the main described combination of OVs with conventional chemotherapeutic agents: platinum salts, mitotic inhibitors, anthracyclines and other antibiotics, anti-metabolites, alkylating agents and topoisomerase inhibitors. Additionally, our work provides an overview of OV combination with targeted therapies: histone deacetylase inhibitors, kinase inhibitors, monoclonal antibodies, inhibitors of DNA repair, inhibitors of the proteasome complex and statins that demonstrated enhanced OV anti-neoplastic activity. Although further studies are required to assess the best combinations to translate the results in the clinic, it is clear that combined therapies, acting with complementary mechanisms of action might be useful to target cancer lesions resistant to currently available treatments.

Immuno-oncology gene expression profiling of formalin-fixed and paraffin-embedded clear cell renal cell carcinoma: Performance comparison of the NanoString nCounter technology with targeted RNA sequencing

Inflammatory gene signatures are currently being explored as predictive biomarkers for immune checkpoint blockade, and particularly for the treatment of renal cell cancers. From a diagnostic point of view, the nCounter analysis platform and targeted RNA sequencing are emerging alternatives to microarrays and comprehensive transcriptome sequencing in assessing formalin-fixed and paraffin-embedded (FFPE) cancer samples. So far, no systematic study has analyzed and compared the technical performance metrics of these two approaches. Filling this gap, we performed a head-to-head comparison of two commercially available immune gene expression assays, using clear cell renal cell cancer FFPE specimens. We compared the nCounter system that utilizes a direct hybridization technology without amplification with an NGS assay that is based on targeted RNA-sequencing with preamplification. We found that both platforms displayed high technical reproducibility and accuracy (Pearson coefficient: ≥0.96, concordance correlation coefficient [CCC]: ≥0.93). A density plot for normalized expression of shared genes on both platforms showed a comparable bi-modal distribution and dynamic range. RNA-Seq demonstrated relatively larger signaling intensity whereas the nCounter system displayed higher inter-sample variability. Estimated fold changes for all shared genes showed high correlation (Spearman coefficient: 0.73). This agreement is even better when only significantly differentially expressed genes were compared. Composite gene expression profiles, such as an interferon gamma (IFNg) signature, can be reliably inferred by both assays. In summary, our study demonstrates that focused transcript read-outs can reliably be achieved by both technologies and that both approaches achieve comparable results despite their intrinsic technical differences.

A historical turning point for the treatment of advanced renal cell carcinoma: inhibition of immune checkpoint

Background: Renal cell carcinoma (RCC) is the most common type of renal malignancy with 87% frequency. As a global health problem, kidney cancer is responsible for 2.2% of new cancer cases. One of the highly effective mechanisms that renal cancer cells avoid in the immune system is PD-1 and PD-L1 interaction.Scope: Literature search is made from PubMed, Medline, and ASCO and ESMO Annual Meeting abstracts using the following search keywords: "nivolumab," "pembrolizumab," "atezolizumab," "avelumab," "durvalumab," and "renal cell cancer." The last search was on November 1, 2019.Findings: The combination of nivolumab and ipilimumab have better survival results than sunitinib for intermediate and poor risk patients but not for favorable risk groups. In 2019, two combination regimens with pembrolizumab plus axitinib and avelumab plus axitinib demonstrated efficacy over sunitinib for every risk group. The overall survival data of these trials are still immature.Conclusions: Advanced RCC has high morbidity and mortality with an increasing prevalence. Following tyrosine kinase inhibitors, checkpoint inhibitors have a great influence on treatment of advanced RCC, especially the combination of these two strategies. In 2019 these combined strategies demonstrated 5% complete remission with up to 60% objective response rate. While not immediately, but perhaps in the near future, advanced RCC will become a manageable chronic disease, even if a cure is not possible.

Anti-VEGF Treatment Enhances CD8+ T-cell Antitumor Activity by Amplifying Hypoxia

Antiangiogenic therapies that target the VEGF pathway have been used clinically to combat cancer for over a decade. Beyond having a direct impact on blood vessel development and tumor perfusion, accumulating evidence indicates that these agents also affect antitumor immune responses. Numerous clinical trials combining antiangiogenic drugs with immunotherapies for the treatment of cancer are ongoing, but a mechanistic understanding of how disruption of tumor angiogenesis may impact immunity is not fully discerned. Here, we reveal that blockade of VEGF-A with a mAb to VEGF augments activation of CD8⁺ T cells within tumors and potentiates their capacity to produce cytokines. We demonstrate that this phenomenon relies on the disruption of VEGFR2 signaling in the tumor microenvironment but does not affect CD8⁺ T cells directly. Instead, the augmented functional capacity of CD8⁺ T cells stems from increased tumor hypoxia that initiates a hypoxia-inducible factor-1α program within CD8⁺ T cells that directly enhances cytokine production. Finally, combinatorial administration of anti-VEGF with an immunotherapeutic antibody, anti-OX40, improved antitumor activity over single-agent treatments. Our findings illustrate that anti-VEGF treatment enhances CD8⁺ T-cell effector function and provides a mechanistic rationale for combining antiangiogenic and immunotherapeutic drugs for cancer treatment.

Avelumab plus axitinib vs sunitinib for advanced renal cell carcinoma: Japanese subgroup analysis from JAVELIN Renal 101

The phase 3 JAVELIN Renal 101 trial of avelumab + axitinib vs sunitinib in patients with treatment-naive advanced renal cell carcinoma (RCC) demonstrated significantly improved progression-free survival (PFS) and higher objective response rate (ORR) with the combination vs sunitinib. Japanese patients enrolled in the study (N = 67) were randomized to receive avelumab + axitinib (N = 33) or sunitinib (N = 34); 67% vs 59% had PD-L1+ tumors (≥1% of immune cells) and 6%/64%/27% vs 6%/82%/12% had International Metastatic Renal Cell Carcinoma Database Consortium (IMDC) favorable/intermediate/poor risk status. In patients who received avelumab + axitinib vs sunitinib, median PFS (95% confidence interval [CI]) was not estimable (8.1 months, not estimable) vs 11.2 months (1.6 months, not estimable) (hazard ratio [HR], 0.49; 95% CI, 0.152, 1.563) in patients with PD-L1+ tumors and 16.6 months (8.1 months, not estimable) vs 11.2 months (4.2 months, not estimable) (HR, 0.66; 95% CI, 0.296, 1.464) in patients irrespective of PD-L1 expression. Median overall survival (OS) has not been reached in either arm in patients with PD-L1+ tumors and irrespective of PD-L1 expression. ORR (95% CI) was 60.6% (42.1%, 77.1%) vs 17.6% (6.8%, 34.5%) in patients irrespective of PD-L1 expression. Common treatment-emergent adverse events (all grade; grade ≥3) in each arm were hand-foot syndrome (64%; 9% vs 71%; 9%), hypertension (55%; 30% vs 44%; 18%), hypothyroidism (55%; 0% vs 24%; 0%), dysgeusia (21%; 0% vs 56%; 0%) and platelet count decreased (3%; 0% vs 65%; 32%). Avelumab + axitinib was efficacious and tolerable in treatment-naive Japanese patients with advanced RCC, which is consistent with results in the overall population.

Regulatory T Cells in Tumor Microenvironment and Approach for Anticancer Immunotherapy

Tregs have a role in immunological tolerance and immune homeostasis by suppressing immune reactions, and its therapeutic potential is critical in autoimmune diseases and cancers. There have been multiple studies conducted on Tregs because of their roles in immune suppression and therapeutic potential. In tumor immunity, Tregs can promote the development and progression of tumors by preventing effective anti-tumor immune responses in tumor-bearing hosts. High infiltration of Tregs into tumor tissue results in poor survival in various types of cancer patients. Identifying factors specifically expressed in Tregs that affect the maintenance of stability and function of Tregs is important for understanding cancer pathogenesis and identifying therapeutic targets. Thus, manipulation of Tregs is a promising anticancer strategy, but finding markers for Treg-specific depletion and controlling these cells require fine-tuning and further research. Here, we discuss the role of Tregs in cancer and the development of Treg-targeted therapies to promote cancer immunotherapy.

Circulating tumor cells in cancer patients: developments and clinical applications for immunotherapy

Cancer metastasis is the leading cause of cancer-related death. Circulating tumor cells (CTCs) are shed into the bloodstream from either primary or metastatic tumors during an intermediate stage of metastasis. In recent years, immunotherapy has also become an important focus of cancer research. Thus, to study the relationship between CTCs and immunotherapy is extremely necessary and valuable to improve the treatment of cancer. In this review, based on the advancements of CTC isolation technologies, we mainly discuss the clinical applications of CTCs in cancer immunotherapy and the related immune mechanisms of CTC formation. In order to fully understand CTC formation, sufficiently and completely understood molecular mechanism based on the different immune cells is critical. This understanding is a promising avenue for the development of effective immunotherapeutic strategies targeting CTCs.

Glasgow PrognosticScore as a Predictor of BevacizumabEfficacy in the First-line Treatment with Metastatic Colorectal Cancer

Background: Inflammation might play an important role in promoting cancer growth partly by affecting tumor angiogenesis. We explored the role of Glasgow prognostic score (GPS) in metastatic colorectal cancer patients receiving first-linebevacizumab.

Methods: All consecutive metastatic colorectal cancer patients treated with first-line chemotherapy plus or not plus bevacizumab were eligible. Pre-treatment GPS were collected for all cases.

Results: In the chemotherapy group for patients with GPS of 0, 1 and 2, median progression-free survival (PFS) was 8.67, 8.10, and 8.27months, respectively (P = 0.17). Median overall survival (OS) was 24.87, 23.30, and 17.93months, respectively (P = 0.04). In the bevacizumab group, median PFS was 11.83, 8.10, and 6.87 months, respectively (P = 0.01), and median OS was 30.80, 19.47, and 18.67 months, respectively (P = 0.03).In whole group patients with a GPS of 0, both PFS and OS were in favor of patients treated with bevacizumab plus chemotherapy compared with who treated with chemotherapy alone (PFS 11.83 vs. 8.67 months, p=0.03; OS 30.80 vs. 24.87 months, p=0.04).

Conclusion: GPS of 0 was correlated with good prognosis. Bevacizumab added a survival advantage only in metastatic colorectal cancer patients with a GPS of 0.

A review of checkpoint inhibitors in the management of renal cell carcinoma

Renal cell carcinoma is a common malignancy of the genitourinary system and is the eight most common cancer type in the United States. The overall incidence of renal cell carcinoma appears to be increasing but death rates have been declining. Patients with poor risk, advanced disease have a two-year survival rate of approximately 7%. Prior to the advent of tyrosine kinase inhibitors, anti-vascular endothelial growth factor antibodies, mammalian target of rapamycin inhibitors, and checkpoint inhibitors, IFN-α and high-dose IL-2, were standard of care treatment options but, conversely, their use is now limited to select patients. Immunotherapies have played a significant role in the treatment of various cancers and have continued to expand. It is of utmost importance that practitioners include checkpoint inhibitors as treatment options for renal cell carcinoma as they mark a new era in the treatment of advanced or relapsed setting. Nivolumab, pembrolizumab, avelumab, ipilimumab, and atezolizumab all play a role in management of disease as either monotherapy or in combination with other agents. Ongoing clinical trials are ongoing to further assess the benefits of inducing cellular immunity in the treatment of renal cell carcinoma. In this article, the available data on immune checkpoint inhibitors for the treatment of advanced or relapsed renal cell carcinoma and their place in therapy are reviewed.

Regulatory T cells in cancer immunosuppression - implications for anticancer therapy

Regulatory T (T_reg) cells, an immunosuppressive subset of CD4⁺ T cells characterized by the expression of the master transcription factor forkhead box protein P3 (FOXP3), are a component of the immune system with essential roles in maintaining self-tolerance. In addition, T_reg cells can suppress anticancer immunity, thereby hindering protective immunosurveillance of neoplasia and hampering effective antitumour immune responses in tumour-bearing hosts, thus promoting tumour development and progression. Identification of the factors that are specifically expressed in T_reg cells and/or that influence T_reg cell homeostasis and function is important to understanding cancer pathogenesis and to identifying therapeutic targets. Immune-checkpoint inhibitors (ICIs) have provided a paradigm shift in the treatment of cancer. Most immune-checkpoint molecules are expressed in T_reg cells, but the effects of ICIs on T_reg cells, and thus the contributions of these cells to treatment responses, remain unclear. Notably, evidence indicates that ICIs targeting programmed cell death 1 (PD-1) might enhance the immunosuppressive function of T_reg cells, whereas cytotoxic T lymphocyte antigen 4 (CTLA-4) inhibitors might deplete these cells. Thus, although manipulation of T_reg cells is a promising anticancer therapeutic strategy, approaches to controlling these cells require further research. Herein, we discuss novel insights into the roles of T_reg cells in cancer, which can hopefully be used to develop T_reg cell-targeted therapies and facilitate immune precision medicine.

Next-generation sequencing and biomarkers for gastric cancer: what is the future?

Recent years have witnessed an improved understanding of tumour biology and the molecular features of gastric cancer. Remarkable advances in next-generation sequencing technologies have defined the genomic landscape of gastric cancer. In fact, several molecular classifications have been proposed, and distinct molecular subtypes have been identified, which could serve as a roadmap for patient stratification and trials of targeted therapies. At present, clinical trials of new agents, such as receptor tyrosine kinases inhibitors, antibody-drug conjugates and IMAB362 (anti-Claudin 18.2), are ongoing. Furthermore, biomarkers of immune checkpoint inhibitors or combination therapy have been ardently investigated. These developments could facilitate precision medicine for gastric cancer in the near future.

Dawn of precision medicine on gastric cancer

BACKGROUND

In recent years, a better understanding of tumor biology and molecular features of gastric cancer has been reached. It may serve as a roadmap for patient stratification and trials of targeted therapies. The apparent efficacy of PD-1 blockade might be limited to a relatively small subset of advanced gastric cancer patients.

MATERIALS AND METHODS

In this study, preclinical and clinical studies, which investigated molecular features, promising treatment targets, and immune checkpoint inhibitor in gastric cancer, were reviewed via PubMed and the congress webpages of the American Society of Clinical Oncology and European Society of Medical Oncology.

RESULTS

Next-generation sequencing technologies have defined the genomic landscape of gastric cancer. Indeed, several molecular classifications have been proposed, and distinct molecular subtypes have been identified. Based on these molecular profiles, clinical trials of new agents such as receptor tyrosine kinases inhibitors, antibody-drug conjugates, and IMAB362 (anti-Claudin 18.2) are ongoing. In addition, biomarkers to predict response during immune checkpoint inhibitors and combination therapy have been enthusiastically investigated.

CONCLUSION

Remarkable advances in an understanding of molecular profiles of gastric cancer enable the development of novel agents. The better treatment selection of immune checkpoint inhibitors or combination therapy should be established. These developments could facilitate precision medicine on gastric cancer in the near future.

Avelumab plus Axitinib versus Sunitinib for Advanced Renal-Cell Carcinoma

BACKGROUND

In a single-group, phase 1b trial, avelumab plus axitinib resulted in objective responses in patients with advanced renal-cell carcinoma. This phase 3 trial involving previously untreated patients with advanced renal-cell carcinoma compared avelumab plus axitinib with the standard-of-care sunitinib.

METHODS

We randomly assigned patients in a 1:1 ratio to receive avelumab (10 mg per kilogram of body weight) intravenously every 2 weeks plus axitinib (5 mg) orally twice daily or sunitinib (50 mg) orally once daily for 4 weeks (6-week cycle). The two independent primary end points were progression-free survival and overall survival among patients with programmed death ligand 1 (PD-L1)-positive tumors. A key secondary end point was progression-free survival in the overall population; other end points included objective response and safety.

RESULTS

A total of 886 patients were assigned to receive avelumab plus axitinib (442 patients) or sunitinib (444 patients). Among the 560 patients with PD-L1-positive tumors (63.2%), the median progression-free survival was 13.8 months with avelumab plus axitinib, as compared with 7.2 months with sunitinib (hazard ratio for disease progression or death, 0.61; 95% confidence interval [CI], 0.47 to 0.79; P<0.001); in the overall population, the median progression-free survival was 13.8 months, as compared with 8.4 months (hazard ratio, 0.69; 95% CI, 0.56 to 0.84; P<0.001). Among the patients with PD-L1-positive tumors, the objective response rate was 55.2% with avelumab plus axitinib and 25.5% with sunitinib; at a median follow-up for overall survival of 11.6 months and 10.7 months in the two groups, 37 patients and 44 patients had died, respectively. Adverse events during treatment occurred in 99.5% of patients in the avelumab-plus-axitinib group and in 99.3% of patients in the sunitinib group; these events were grade 3 or higher in 71.2% and 71.5% of the patients in the respective groups.

CONCLUSIONS

Progression-free survival was significantly longer with avelumab plus axitinib than with sunitinib among patients who received these agents as first-line treatment for advanced renal-cell carcinoma. (Funded by Pfizer and Merck [Darmstadt, Germany]; JAVELIN Renal 101 ClinicalTrials.gov number, NCT02684006.).

A peptide mimicking the binding sites of VEGF-A and VEGF-B inhibits VEGFR-1/-2 driven angiogenesis, tumor growth and metastasis

Interfering with interactions of vascular endothelial growth factors (VEGFs) with their receptors (VEGFRs) effectively inhibits angiogenesis and tumor growth. We designed an antagonist peptide of VEGF-A and VEGF-B reproducing two discontinuous receptor binding regions of VEGF-B (loop 1 and loop3) covalently linked together by a receptor binding region of VEGF-A (loop3). The designed peptide (referred to as VGB4) was able to bind to both VEGFR1 and VEGFR2 on the Human Umbilical Vein Endothelial Cells (HUVECs) surface and inhibited VEGF-A driven proliferation, migration and tube formation in HUVECs through suppression of ERK1/2 and AKT phosphorylation. The whole-animal fluorescence imaging demonstrated that fluorescein isothiocyanate (FITC)-VGB4 accumulated in the mammary carcinoma tumors (MCTs). Administration of VGB4 led to the regression of 4T1 murine MCT growth through decreased expression of p-VEGFR1 and p-VEGFR2 and abrogation of ERK1/2 and AKT activation followed by considerable decrease of tumor cell proliferation (Ki67 expression) and angiogenesis (CD31 and CD34 expression), induction of apoptosis (increased p53 expression, TUNEL staining and decreased Bcl2 expression), and suppression of metastasis  (increased E-cadherin and decreased N-cadherin, NF-κB and MMP-9 expression). These findings indicate that VGB4 may be applicable for antiangiogenic and antitumor therapy.

Improved Multiplex Immunohistochemistry for Immune Microenvironment Evaluation of Mouse Formalin-Fixed, Paraffin-Embedded Tissues

Immune profiling of tissue through multiplex immunohistochemistry is important for the investigation of immune cell dynamics, and it can contribute to disease prognosis and evaluation of treatment response in cancer patients. However, protocols for mouse formalin-fixed, paraffin-embedded tissue have been less successful. Given that formalin fixation and paraffin embedding remains the most common preparation method for processing mouse tissue, this has limited the options to study the immune system and the impact of novel therapeutics in preclinical models. In an attempt to address this, we developed an improved immunohistochemistry protocol with a more effective Ag-retrieval buffer. We also validated 22 Abs specific for mouse immune cell markers to distinguish B cells, T cells, NK cells, macrophages, dendritic cells, and neutrophils. In addition, we designed and tested novel strategies to identify immune cells for which unique Abs are currently not available. Last, in the 4T1 model of breast cancer, we demonstrate the utility of our protocol and Ab panels in the quantitation and spatial distribution of immune cells.

Recruited bone marrow derived cells, local stromal cells and IL-17 at the front line of resistance development to anti-VEGF targeted therapies

Although anti-angiogenic agents targeting VEGF have shown affordable beneficial outcomes in several human cancer types, in most pre-clinical and clinical studies, these effects are transient and followed by rapid relapse and tumor regrowth. Recently, it has been suggested that recruited bone marrow derived cells (BMDCs) to the tumor-microenvironment together with stromal cells play an important role in development of resistance to anti-VEGF therapies. Additionally, acquired resistance to anti-VEGF therapies has shown to be mediated partly through overexpression of different pro-angiogenic cytokines and growth factors including G-CSF, IL-6, IL-8, VEGF and FGF by these cells. Alongside, IL-17, a pro-inflammatory cytokine, mostly secreted by infiltrated CD4⁺ T helper cells, has shown to mediate resistance to anti-VEGF therapies, through recruiting BMDCs and modulating stromal cells activities including endothelial cells, tumor associated macrophages and cancer associated fibroblasts. Here, we examined the role of BMDCs, tumor stromal cells, IL-17 and their negotiation in development of resistance to anti-VEGF targeted therapies.

Metabotropic glutamate receptor-1 regulates inflammation in triple negative breast cancer

Breast cancer remains a major cause of death among women. 15% of these cancers are triple negative breast cancer (TNBC), an aggressive subtype of breast cancer for which no current effective targeted therapy exists. We have previously demonstrated a role for mGluR1 in mediating tumor cell growth, endothelial cell proliferation, and tumor-induced angiogenesis in TNBC. In this study, we explore a role for mGluR1 in regulating inflammation in TNBC. GRM1 expression was silenced in MDA-MB-231 cells to study changes in expression of inflammatory genes regulated by mGluR1. Results were confirmed by ELISA using GRM1-silenced and overexpressed cells and mGluR1 inhibitors. A functional role for these differentially expressed genes was determined in vitro and in vivo. 131 genes were differentially expressed in GRM1-silenced MDA-MB-231 cells, with some of these falling into four major canonical pathways associated with acute inflammation, specifically leukocyte migration/chemotaxis. Upregulation of three of these genes (CXCL1, IL6, IL8) and their corresponding protein was confirmed by qPCR analysis and ELISA in GRM1-manipulated TNBC cells. Upregulation of these cytokines enhanced endothelial adhesion and transmigration of neutrophils in co-culture assays and in 4T1 mouse tumors. Our results suggest mGluR1 may serve as a novel endogenous regulator of inflammation in TNBC.

Oncolytic Viruses on Drugs: Achieving Higher Therapeutic Efficacy

Over the past 20 years there has been a dramatic expansion in the testing of oncolytic viruses (OVs) for the treatment of cancer. OVs are unique biotherapeutics that induce multimodal responses toward tumors, from direct cytopathic effects on cancer cells, to tumor associated blood vessel disruption, and ultimately potent stimulation of anti-tumor immune activation. These agents are highly targeted and can be efficacious as cancer treatments resulting in some patients experiencing complete tumor regression and even cures from OV monotherapy. However, most patients have limited responses with viral replication in tumors often found to be modest and transient. To augment OV replication, increase bystander killing of cancer cells, and/or stimulate stronger targeted anti-cancer immune responses, drug combination approaches have taken center stage for translation to the clinic. Here we comprehensively review drugs that have been combined with OVs to increase therapeutic efficacy, examining the proposed mechanisms of action, and we discuss trends in pharmaco-viral immunotherapeutic approaches currently being investigated.

Atezolizumab for First-Line Treatment of Metastatic Nonsquamous NSCLC

BACKGROUND

The cancer-cell-killing property of atezolizumab may be enhanced by the blockade of vascular endothelial growth factor-mediated immunosuppression with bevacizumab. This open-label, phase 3 study evaluated atezolizumab plus bevacizumab plus chemotherapy in patients with metastatic nonsquamous non-small-cell lung cancer (NSCLC) who had not previously received chemotherapy.

METHODS

We randomly assigned patients to receive atezolizumab plus carboplatin plus paclitaxel (ACP), bevacizumab plus carboplatin plus paclitaxel (BCP), or atezolizumab plus BCP (ABCP) every 3 weeks for four or six cycles, followed by maintenance therapy with atezolizumab, bevacizumab, or both. The two primary end points were investigator-assessed progression-free survival both among patients in the intention-to-treat population who had a wild-type genotype (WT population; patients with EGFR or ALK genetic alterations were excluded) and among patients in the WT population who had high expression of an effector T-cell (Teff) gene signature in the tumor (Teff-high WT population) and overall survival in the WT population. The ABCP group was compared with the BCP group before the ACP group was compared with the BCP group.

RESULTS

In the WT population, 356 patients were assigned to the ABCP group, and 336 to the BCP group. The median progression-free survival was longer in the ABCP group than in the BCP group (8.3 months vs. 6.8 months; hazard ratio for disease progression or death, 0.62; 95% confidence interval [CI], 0.52 to 0.74; P<0.001); the corresponding values in the Teff-high WT population were 11.3 months and 6.8 months (hazard ratio, 0.51 [95% CI, 0.38 to 0.68]; P<0.001). Progression-free survival was also longer in the ABCP group than in the BCP group in the entire intention-to-treat population (including those with EGFR or ALK genetic alterations) and among patients with low or negative programmed death ligand 1 (PD-L1) expression, those with low Teff gene-signature expression, and those with liver metastases. Median overall survival among the patients in the WT population was longer in the ABCP group than in the BCP group (19.2 months vs. 14.7 months; hazard ratio for death, 0.78; 95% CI, 0.64 to 0.96; P=0.02). The safety profile of ABCP was consistent with previously reported safety risks of the individual medicines.

CONCLUSIONS

The addition of atezolizumab to bevacizumab plus chemotherapy significantly improved progression-free survival and overall survival among patients with metastatic nonsquamous NSCLC, regardless of PD-L1 expression and EGFR or ALK genetic alteration status. (Funded by F. Hoffmann-La Roche/Genentech; IMpower150 ClinicalTrials.gov number, NCT02366143 .).

Clinical activity and molecular correlates of response to atezolizumab alone or in combination with bevacizumab versus sunitinib in renal cell carcinoma

We describe results from IMmotion150, a randomized phase 2 study of atezolizumab (anti-PD-L1) alone or combined with bevacizumab (anti-VEGF) versus sunitinib in 305 patients with treatment-naive metastatic renal cell carcinoma. Co-primary endpoints were progression-free survival (PFS) in intent-to-treat and PD-L1+ populations. Intent-to-treat PFS hazard ratios for atezolizumab + bevacizumab or atezolizumab monotherapy versus sunitinib were 1.0 (95% confidence interval (CI), 0.69-1.45) and 1.19 (95% CI, 0.82-1.71), respectively; PD-L1+ PFS hazard ratios were 0.64 (95% CI, 0.38-1.08) and 1.03 (95% CI, 0.63-1.67), respectively. Exploratory biomarker analyses indicated that tumor mutation and neoantigen burden were not associated with PFS. Angiogenesis, T-effector/IFN-γ response, and myeloid inflammatory gene expression signatures were strongly and differentially associated with PFS within and across the treatments. These molecular profiles suggest that prediction of outcomes with anti-VEGF and immunotherapy may be possible and offer mechanistic insights into how blocking VEGF may overcome resistance to immune checkpoint blockade.

Suppressive role of myeloid-derived suppressor cells (MDSCs) in the microenvironment of breast cancer and targeted immunotherapies

Myeloid-derived suppressor cells (MDSCs) play a pivotal role in promoting tumor growth and metastasis and can even decrease the efficacy of immunotherapy. In breast cancer, MDSCs are recruited mainly by breast cancer cells to form a tumor-favoring microenvironment to suppress the anti-tumor immune response. In addition, MDSCs can react directly with breast cancer cells. In this paper, we describe several ways to recruit MDSCs in breast cancer, including breast cancer cell-derived cytokines and chemokines. The intracellular pathways in MDSCs during recruitment are classified as the STAT3-NF-κB-IDO pathway, the STAT3/IRF-8 pathway and the PTEN/Akt pathway. MDSCs act on T cells and NK cells to suppress the body's immunity, and via IL-6 trans-signaling, promote breast cancer directly. We further describe MDSC-targeted immune therapies for breast cancer, which are classified as: preventing the formation of MDSCs, eliminating MDSDCs, and reducing the products of MDSCs. Furthermore, MDSC-targeted immunotherapy potentiates the effect of the other immunotherapies. Based on the facts that MSDCs have significant roles in breast cancer malignant behaviors and can be suppressed by various strategies, we do believe MDSC-targeted immunotherapy presents a broad prospect in the future.

Towards predictive biomarkers for immunotherapy response in breast cancer patients

Immunotherapy using anti-PD(L)1 has revolutionized treatment for various tumor types. Early data have shown durable responses in a small subgroup of breast cancer patients. So far, the response rates appear higher for breast tumors that are triple negative, PDL1-positive and/or harbor high levels of immune cells. Both comprehensive analyses of the breast tumor microenvironment and exploiting research on biomarkers in other cancer types, such as melanoma and lung cancer, may contribute to the discovery of accurate biomarkers to select breast cancer patients for immunotherapy. Here we summarize key features of the breast tumor microenvironment as well as putative predictive biomarkers established in other tumor types. Insights from both fields can guide future studies to enable personalized breast cancer immunotherapy.

Human Placental-Derived Adherent Stromal Cells Co-Induced with TNF-α and IFN-γ Inhibit Triple-Negative Breast Cancer in Nude Mouse Xenograft Models

Culturing 3D-expanded human placental-derived adherent stromal cells (ASCs) in the presence of tumor necrosis factor-alpha (TNF-α) and interferon-gamma (IFN-γ) transiently upregulated the secretion of numerous anti-proliferative, anti-angiogenic and pro-inflammatory cytokines. In a 3D-spheroid screening assay, conditioned medium from these induced-ASCs inhibited proliferation of cancer cell lines, including triple-negative breast cancer (TNBC) lines. In vitro co-culture studies of induced-ASCs with MDA-MB-231 human breast carcinoma cells, a model representing TNBC, supports a mechanism involving immunomodulation and angiogenesis inhibition. In vivo studies in nude mice showed that intramuscular administration of induced-ASCs halted MDA-MB-231 cell proliferation, and inhibited tumor progression and vascularization. Thirty percent of treated mice experienced complete tumor remission. Murine serum concentrations of the tumor-supporting cytokines Interleukin-6 (IL-6), Vascular endothelial growth factor (VEGF) and Granulocyte-colony stimulating factor (G-CSF) were lowered to naïve levels. A somatic mutation analysis identified numerous genes which could be screened in patients to increase a positive therapeutic outcome. Taken together, these results show that targeted changes in the secretion profile of ASCs may improve their therapeutic potential.

Inflammatory indexes as predictors of prognosis and bevacizumab efficacy in patients with metastatic colorectal cancer

Background

To investigate the role of pre-treatment inflammatory indexes (II) as predictors of prognosis and treatment efficacy in patients with metastatic colorectal cancer mCRC randomized onto the prospective multicenter randomized ITACa (Italian Trial in Advanced Colorectal Cancer) trial to receive first-line chemotherapy (CT) with or without bevacizumab (Bev).

Results

In the overall population, PFS and OS were higher in patients with low SII (p = .015 and .002, respectively), low NLR (p = .0001 and <.0001, respectively) and low PLR (p = .004 and .008, respectively). Patients with low NLR in the CT plus Bev arm had a higher PFS than those treated with CT alone (HR = 0.69, p = .021).

Patients and Methods

Two hundred and eighty-nine patients were considered for this study, 141 receiving CT plus Bev and 148 receiving CT alone. The pre-treatment systemic immune-inflammation index (SII), neutrophil-to-lymphocyte ratio (NLR) and platelet-lymphocyte ratio (PLR) were evaluated to identify a potential correlation with progression-free (PFS) and overall survival (OS) in both the overall population and the 2 treatment arms.

Conclusion

Our results indicate that II, in particular NLR, are good prognostic and predictive markers for mCRC patients who are candidates for CT plus Bev.

Sunitinib enhances the antitumor responses of agonistic CD40-antibody by reducing MDSCs and synergistically improving endothelial activation and T-cell recruitment

CD40-activating immunotherapy has potent antitumor effects due to its ability to activate dendritic cells and induce cytotoxic T-cell responses. However, its efficacy is limited by immunosuppressive cells in the tumor and by endothelial anergy inhibiting recruitment of T-cells. Here, we show that combining agonistic CD40 monoclonal antibody (mAb) therapy with vascular targeting using the tyrosine kinase inhibitor sunitinib decreased tumor growth and improved survival in B16.F10 melanoma and T241 fibrosarcoma. Treatment of tumor-bearing mice with anti-CD40 mAb led to increased activation of CD11c+ dendritic cells in the tumor draining lymph node, while sunitinib treatment reduced vessel density and decreased accumulation of CD11b+Gr1+ myeloid derived suppressor cells. The expression of ICAM-1 and VCAM-1 adhesion molecules was up-regulated on tumor endothelial cells only when anti-CD40 mAb treatment was combined with sunitinib. This was associated with enhanced intratumoral infiltration of CD8+ cytotoxic T-cells. Our results show that combining CD40-stimulating immunotherapy with sunitinib treatment exerts potent complementary antitumor effects mediated by dendritic cell activation, a reduction in myeloid derived suppressor cells and increased endothelial activation, resulting in enhanced recruitment of cytotoxic T-cells.

Targeting immune checkpoints in breast cancer: an update of early results

The immune tumour microenvironment has been shown to play a crucial role in the development and progression of cancer. Expression of gene signatures, reflecting immune activation, and the presence of tumour-infiltrating lymphocytes were associated with favourable outcomes in HER2-positive and triple-negative breast cancer. Recently, immunotherapy with immune checkpoint blockade induced long-lasting responses and improved survival in hard-to-treat malignancies (ie, melanoma and non-small cell lung cancer) and are changing treatment paradigms in a variety of neoplastic diseases. Immune checkpoint blockade has been evaluated in breast cancer, particularly in the triple-negative subtype, with promising results observed in monotherapy or in combination with chemotherapy in the metastatic and neoadjuvant settings. However, identification of patients who are most likely to benefit from immune checkpoint blockade remains challenging, with many patients not responding to treatments and a significant financial cost. The combination of immune checkpoint blockade with conventional cancer treatments such as chemotherapy, radiotherapy, targeted therapies or with other immunotherapies is a promising strategy to potentiate its efficacy in breast cancer although further research is required to effectively identify who will respond to these immunotherapies. In this review we report the most recent results that emerged from trials testing immune checkpoint blockade and potential predictive biomarkers and emphasise the new strategies that are under clinical development in breast cancer.