Bevacizumab plus ipilimumab in patients with metastatic melanoma

Mechanisms of resistance to targeted therapy and immunotherapy in non-small cell lung cancer: promising strategies to overcoming challenges

Resistance to targeted therapy and immunotherapy in non-small cell lung cancer (NSCLC) is a significant challenge in the treatment of this disease. The mechanisms of resistance are multifactorial and include molecular target alterations and activation of alternative pathways, tumor heterogeneity and tumor microenvironment change, immune evasion, and immunosuppression. Promising strategies for overcoming resistance include the development of combination therapies, understanding the resistance mechanisms to better use novel drug targets, the identification of biomarkers, the modulation of the tumor microenvironment and so on. Ongoing research into the mechanisms of resistance and the development of new therapeutic approaches hold great promise for improving outcomes for patients with NSCLC. Here, we summarize diverse mechanisms driving resistance to targeted therapy and immunotherapy in NSCLC and the latest potential and promising strategies to overcome the resistance to help patients who suffer from NSCLC.

Complete remission in a pretreated, microsatellite-stable, KRAS-mutated colon cancer patient after treatment with sintilimab and bevacizumab and platinum-based chemotherapy: a case report and literature review

Metastatic colon cancer remains an incurable disease, and it is difficult for existing treatments to achieve the desired clinical outcome, especially for colon cancer patients who have received first-line treatment. Although immune checkpoint inhibitors (ICIs) have demonstrated durable clinical efficacy in a variety of solid tumors, their response requires an inflammatory tumor microenvironment. However, microsatellite-stable (MSS) colon cancer, which accounts for the majority of colorectal cancers, is a cold tumor that does not respond well to ICIs. Combination regimens open the door to the utility of ICIs in cold tumors. Although combination therapies have shown their advantage even for MSS colon cancer, it remains unclear whether combination therapies show their advantage in patients with pretreated metastatic colon cancer. We report a patient who has achieved complete remission and good tolerance with sintilimab plus bevacizumab and platinum-based chemotherapy after postoperative recurrence. The patient had KRAS mutation and MSS-type colon cancer, and his PD-1+CD8+ and CD3-CD19-CD14+CD16-HLA-DR were both positive. He has achieved a progression-free survival of 43 months and is still being followed up at our center. The above results suggest that this therapeutic regimen is a promising treatment modality for the management of pretreated, MSS-type and KRAS-mutated metastatic colorectal cancer although its application to the general public still needs to be validated in clinical trials.

Diagnostic and Therapeutic Particularities of Symptomatic Melanoma Brain Metastases from Case Report to Literature Review

The recent introduction of immunotherapy and targeted therapy has substantially enriched the therapeutic landscape of metastatic melanoma. However, cerebral metastases remain unrelenting entities with atypical metabolic and genetic profiles compared to extracranial metastases, requiring combined approaches with local ablative treatment to alleviate symptoms, prevent recurrence and restore patients' biological and psychological resources for fighting malignancy. This paper aims to provide the latest scientific evidence about the rationale and timing of treatment, emphasizing the complementary roles of surgery, radiotherapy, and systemic therapy in eradicating brain metastases, with a special focus on the distinct response of intracranial and extracranial disease, which are regarded as separate molecular entities. To illustrate the complexity of designing individualized therapeutic schemes, we report a case of delayed BRAF-mutant diagnosis, an aggressive forearm melanoma, in a presumed psychiatric patient whose symptoms were caused by cerebral melanoma metastases. The decision to administer molecularly targeted therapy was dictated by the urgency of diminishing the tumor burden for symptom control, due to potentially life-threatening complications caused by the flourishing of extracranial disease in locations rarely reported in living patients, further proving the necessity of multidisciplinary management.

Magnetic resonance imaging-based approaches for detecting the efficacy of combining therapy following VEGFR-2 and PD-1 blockade in a colon cancer model

BACKGROUND

Angiogenesis inhibitors have been identified to improve the efficacy of immunotherapy in recent studies. However, the delayed therapeutic effect of immunotherapy poses challenges in treatment planning. Therefore, this study aims to explore the potential of non-invasive imaging techniques, specifically intravoxel-incoherent-motion diffusion-weighted imaging (IVIM-DWI) and blood oxygenation level-dependent magnetic resonance imaging (BOLD-MRI), in detecting the anti-tumor response to the combination therapy involving immune checkpoint blockade therapy and anti-angiogenesis therapy in a tumor-bearing animal model.

METHODS

The C57BL/6 mice were implanted with murine MC-38 cells to establish colon cancer xenograft model, and randomly divided into the control group, anti-PD-1 therapy group, and combination therapy group (VEGFR-2 inhibitor combined with anti-PD-1 antibody treatment). All mice were imaged before and, on the 3rd, 6th, 9th, and 12th day after administration, and pathological examinations were conducted at the same time points.

RESULTS

The combination therapy group effectively suppressed tumor growth, exhibiting a significantly higher tumor inhibition rate of 69.96% compared to the anti-PD-1 group (56.71%). The f value and D* value of IVIM-DWI exhibit advantages in reflecting tumor angiogenesis. The D* value showed the highest correlation with CD31 (r = 0.702, P = 0.001), and the f value demonstrated the closest correlation with vessel maturity (r = 0.693, P = 0.001). While the BOLD-MRI parameter, R2* value, shows the highest correlation with Hif-1α(r = 0.778, P < 0.001), indicating the capability of BOLD-MRI to evaluate tumor hypoxia. In addition, the D value of IVIM-DWI is closely related to tumor cell proliferation, apoptosis, and infiltration of lymphocytes. The D value was highly correlated with Ki-67 (r = - 0.792, P < 0.001), TUNEL (r = 0.910, P < 0.001) and CD8a (r = 0.918, P < 0.001).

CONCLUSIONS

The combination of VEGFR-2 inhibitors with PD-1 immunotherapy shows a synergistic anti-tumor effect on the mouse colon cancer model. IVIM-DWI and BOLD-MRI are expected to be used as non-invasive approaches to provide imaging-based evidence for tumor response detection and efficacy evaluation.

Outcome of Atezolizumab Plus Bevacizumab Combination Therapy in High-Risk Patients with Advanced Hepatocellular Carcinoma

Real-world data regarding treatment with atezolizumab plus bevacizumab in high-risk patients with advanced HCC are lacking. In this multicenter retrospective cohort study, a total of 215 patients with advanced HCC received atezolizumab plus bevacizumab treatment at four tertiary hospitals. High-risk patients were those with grade Vp4 portal vein thrombus, bile duct invasion, or more than 50% liver infiltration. In total, 98 (45.6%) were the high-risk population, 186 (86.5%) were considered to be Child-Pugh class A, and 128 (59.5%) had previously received neoadjuvant or concomitant radiation treatment. Median overall survival (OS) was 11.25 months (95% CI, 9.50-13.10), and the median progression-free survival (PFS) was 8.00 months (95% CI, 6.82-9.18). In the high-risk population, the median OS was 10 months (95% CI, 8.19-11.82) and the median PFS was 6.50 months (95% CI, 3.93-9.08). In the high-risk population, multivariate analysis indicated that radiation therapy and lower ALBI grade were associated with better OS and PFS. A total of 177 (82.3%) patients experienced adverse events of any grade, the most common being proteinuria (23.7%). Atezolizumab plus bevacizumab treatment showed consistent efficacy and tolerability in both the total and high-risk population. Radiation therapy combined with atezolizumab plus bevacizumab treatment might be helpful to improve PFS and OS in high-risk populations.

Durvalumab plus pazopanib combination in patients with advanced soft tissue sarcomas: a phase II trial

We aimed to determine the activity of the anti-VEGF receptor tyrosine-kinase inhibitor, pazopanib, combined with the anti-PD-L1 inhibitor, durvalumab, in metastatic and/or recurrent soft tissue sarcoma (STS). In this single-arm phase 2 trial (NCT03798106), treatment consisted of pazopanib 800 mg orally once a day and durvalumab 1500 mg once every 3 weeks. Primary outcome was overall response rate (ORR) and secondary outcomes included progression-free survival (PFS), overall survival, disease control rate, immune-related response criteria, and safety. The ORR was 30.4% and the trial met the pre-specified endpoint. The median PFS was 7.7 months (95% confidence interval: 5.7-10.4). The common treatment-related adverse events of grades 3-4 included neutropenia (9 [19.1%]), elevated aspartate aminotransferase (7 [14.9%]), alanine aminotransferase (5 [10.6%]), and thrombocytopenia (4 [8.5%]). In a prespecified transcriptomic analysis, the B lineage signature was a significant key determinant of overall response (P = 0.014). In situ analysis also showed that tumours with high CD20+ B cell infiltration and vessel density had a longer PFS (P = 6.5 × 10-4) than those with low B cell infiltration and vessel density, as well as better response (50% vs 12%, P = 0.019). CD20+ B cell infiltration was identified as the only independent predictor of PFS via multivariate analysis. Durvalumab combined with pazopanib demonstrated promising efficacy in an unselected STS cohort, with a manageable toxicity profile.

Ziv-aflibercept plus pembrolizumab in patients with advanced melanoma resistant to anti-PD-1 treatment

BACKGROUND

Vascular endothelial growth factor is associated with reduced immune response and impaired anti-tumor activity. Combining antiangiogenic agents with immune checkpoint inhibition can overcome this immune suppression and enhance treatment efficacy.

METHODS

This study investigated the combination of ziv-aflibercept anti-angiogenic therapy with pembrolizumab in patients with advanced melanoma resistant to anti-PD-1 treatment. Baseline and on-treatment plasma and PBMC samples were analyzed by multiplex protein assay and mass cytometry, respectively.

RESULTS

In this Phase 1B study (NCT02298959), ten patients with advanced PD-1-resistant melanoma were treated with a combination of ziv-aflibercept (at 2-4 mg/kg) plus pembrolizumab (at 2 mg/kg), administered intravenously every 2 weeks. Two patients (20%) achieved a partial response, and two patients (20%) experienced stable disease (SD) as the best response. The two responders had mucosal melanoma, while both patients with SD had ocular melanoma. The combination therapy demonstrated clinical activity and acceptable safety, despite the occurrence of adverse events. Changes in plasma analytes such as platelet-derived growth factor and PD-L1 were explored, indicating potential alterations in myeloid cell function. Higher levels of circulating CXCL10 in non-responding patients may reflect pro-tumor activity. Specific subsets of γδ T cells were associated with poor clinical outcomes, suggesting impaired γδ T-cell function in non-responding patients.

CONCLUSIONS

Although limited by sample size and follow-up, these findings highlight the potential of the combination of ziv-aflibercept antiangiogenic therapy with pembrolizumab in patients with advanced melanoma resistant to anti-PD-1 treatment and the need for further research to improve outcomes in anti-PD-1-resistant melanoma.

TRIAL REGISTRATION NUMBER

NCT02298959.

Ocular Surface Side Effects of Novel Anticancer Drugs

Surgery, anticancer drugs (chemotherapy, hormonal medicines, and targeted treatments), and/or radiation are common treatment strategies for neoplastic diseases. Anticancer drugs eliminate malignant cells through the inhibition of specific pathways that contribute to the formation and development of cancer. Given the ability of such pharmacological medications to combat cancerous cells, their role in the management of neoplastic diseases has become essential. However, these drugs may also lead to undesirable systemic and ocular adverse effects due to cyto/neuro-toxicity and inflammatory reactions. Ocular surface side effects are recognized to significantly impact patient's quality of life and quality of vision. Blepharoconjunctivitis is known to be a common side effect caused by oxaliplatin, cyclophosphamide, cytarabine, and docetaxel, while anastrozole, methotrexate, and 5-fluorouracil can all determine dry eye disease. However, the potential processes involved in the development of these alterations are yet not fully understood, especially for novel drugs currently available for cancer treatment. This review aims at analyzing the potential ocular surface and adnexal side effects of novel anticancer medications, trying to provide a better understanding of the underlying pharmacological processes and useful insights on the choice of proper management.

EDIL3 as an Angiogenic Target of Immune Exclusion Following Checkpoint Blockade

Immune checkpoint blockade (ICB) has become the standard of care for several solid tumors. Multiple combinatorial approaches have been studied to improve therapeutic efficacy. The combination of antiangiogenic agents and ICB has demonstrated efficacy in several cancers. To improve the mechanistic understanding of synergies with these treatment modalities, we performed screens of sera from long-term responding patients treated with ipilimumab and bevacizumab. We discovered a high-titer antibody response against EGF-like repeats and discoidin I-like domains protein 3 (EDIL3) that correlated with favorable clinical outcomes. EDIL3 is an extracellular protein, previously identified as a marker of poor prognosis in various malignancies. Our Tumor Immune Dysfunction and Exclusion analysis predicted that EDIL3 was associated with immune exclusion signatures for cytotoxic immune cell infiltration and nonresponse to ICB. Cancer-associated fibroblasts (CAF) were predicted as the source of EDIL3 in immune exclusion-related cells. Furthermore, The Cancer Genome Atlas Skin Cutaneous Melanoma (TCGA-SKCM) and CheckMate 064 data analyses correlated high levels of EDIL3 with increased pan-fibroblast TGFβ response, enrichment of angiogenic signatures, and induction of epithelial-to-mesenchymal transition. Our in vitro studies validated EDIL3 overexpression and TGFβ regulation in patient-derived CAFs. In pretreatment serum samples from patients, circulating levels of EDIL3 were associated with circulating levels of VEGF, and like VEGF, EDIL3 increased the angiogenic abilities of patient-derived tumor endothelial cells (TEC). Mechanistically, three-dimensional microfluidic cultures and two-dimensional transmigration assays with TEC endorsed EDIL3-mediated disruption of the lymphocyte function-associated antigen-1 (LFA-1)-ICAM-1 interaction as a possible means of T-cell exclusion. We propose EDIL3 as a potential target for improving the transendothelial migration of immune cells and efficacy of ICB therapy.

Resistance to immune checkpoint therapies by tumour-induced T-cell desertification and exclusion: key mechanisms, prognostication and new therapeutic opportunities

Immune checkpoint therapies (ICT) can reinvigorate the effector functions of anti-tumour T cells, improving cancer patient outcomes. Anti-tumour T cells are initially formed during their first contact (priming) with tumour antigens by antigen-presenting cells (APCs). Unfortunately, many patients are refractory to ICT because their tumours are considered to be 'cold' tumours-i.e., they do not allow the generation of T cells (so-called 'desert' tumours) or the infiltration of existing anti-tumour T cells (T-cell-excluded tumours). Desert tumours disturb antigen processing and priming of T cells by targeting APCs with suppressive tumour factors derived from their genetic instabilities. In contrast, T-cell-excluded tumours are characterised by blocking effective anti-tumour T lymphocytes infiltrating cancer masses by obstacles, such as fibrosis and tumour-cell-induced immunosuppression. This review delves into critical mechanisms by which cancer cells induce T-cell 'desertification' and 'exclusion' in ICT refractory tumours. Filling the gaps in our knowledge regarding these pro-tumoral mechanisms will aid researchers in developing novel class immunotherapies that aim at restoring T-cell generation with more efficient priming by APCs and leukocyte tumour trafficking. Such developments are expected to unleash the clinical benefit of ICT in refractory patients.

Checkpoint inhibitors and anti-angiogenic agents: a winning combination

The combination of immune checkpoint inhibitors and anti-angiogenic agents is a promising new approach in cancer treatment. Immune checkpoint inhibitors block the signals that help cancer cells evade the immune system, while anti-angiogenic agents target the blood vessels that supply the tumour with nutrients and oxygen, limiting its growth. Importantly, this combination triggers synergistic effects based on molecular and cellular mechanisms, leading to better response rates and longer progression-free survival than treatment alone. However, these combinations can also lead to increased side effects and require close monitoring.

Immune-Based Combination Therapies for Advanced Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the fourth most frequent cause of cancer-related death worldwide. HCC frequently presents as advanced disease at diagnosis, and disease relapse following radical surgery is frequent. In recent years, immune checkpoint inhibitors (ICIs) have revolutionized the treatment of advanced HCC, particularly with the introduction of atezolizumab/bevacizumab as the new standard of care for first-line treatment. Recently, dual immune checkpoint blockade with durvalumab plus tremelimumab has also emerged as an effective first-line treatment for advanced HCC and most of the research is currently focused on developing combination treatments based mainly on ICIs. In this review, we will discuss the rationale and ongoing clinical trials of immune-based combination therapies for the treatment of advanced HCC, also focusing on new immunotherapy strategies such as chimeric antigen receptor T cells (CAR-T) and anti-cancer vaccines.

Exploring the crosstalk between endothelial cells, immune cells, and immune checkpoints in the tumor microenvironment: new insights and therapeutic implications

The tumor microenvironment (TME) is a highly intricate milieu, comprising a multitude of components, including immune cells and stromal cells, that exert a profound influence on tumor initiation and progression. Within the TME, angiogenesis is predominantly orchestrated by endothelial cells (ECs), which foster the proliferation and metastasis of malignant cells. The interplay between tumor and immune cells with ECs is complex and can either bolster or hinder the immune system. Thus, a comprehensive understanding of the intricate crosstalk between ECs and immune cells is essential to advance the development of immunotherapeutic interventions. Despite recent progress, the underlying molecular mechanisms that govern the interplay between ECs and immune cells remain elusive. Nevertheless, the immunomodulatory function of ECs has emerged as a pivotal determinant of the immune response. In light of this, the study of the relationship between ECs and immune checkpoints has garnered considerable attention in the field of immunotherapy. By targeting specific molecular pathways and signaling molecules associated with ECs in the TME, novel immunotherapeutic strategies may be devised to enhance the efficacy of current treatments. In this vein, we sought to elucidate the relationship between ECs, immune cells, and immune checkpoints in the TME, with the ultimate goal of identifying novel therapeutic targets and charting new avenues for immunotherapy.

β2-adrenergic receptor expression in patients receiving bevacizumab therapy for metastatic melanoma

BACKGROUND

Vascular endothelial growth factor (VEGF) was initially known as vascular permeability factor and identified as a driver of tumour angiogenesis. Recently, its role in supporting an immunosuppressive tumour microenvironment was demonstrated, and anti-VEGF treatment combined with immune checkpoint blockade is currently investigated. Further, beta-adrenergic signalling as a modifier of cancer hallmarks like immune response, angiogenesis and metastasis gained increased attention during past years.

METHODS

Focusing on the aspect of immunosuppression in upregulated beta-adrenergic signalling, we investigated predictive markers in patients with metastatic melanoma who received bevacizumab monotherapy, a specific VEGF-A binding antibody. We explored the expression of beta-2 adrenergic receptor (β2-AR), interleukin 6-receptor (IL6-R), cyclooxygenase 2 (COX2) and VEGF-A by immunohistochemistry in melanoma to assess the correlation between these proteins in melanoma cells and response to treatment.

RESULTS

Strong β2-AR expression in metastases was associated with clinical benefit of bevacizumab. Furthermore, expression of the latter was positively linked to expression of VEGF-A and COX2. β2-AR expression in melanoma metastasis appears to distinguish a subgroup of patients that might benefit from anti-VEGF treatment.

CONCLUSION

Our results strengthen further exploration of anti-VEGF therapy in combination with immune checkpoint blockade in clinical studies and the investigation of β2-AR as predictive marker.

Advances in targeted therapy and immunotherapy for melanoma (Review)

Melanoma is the most aggressive and deadly type of skin cancer and is known for its poor prognosis as soon as metastasis occurs. Since 2011, new and effective therapies for metastatic melanoma have emerged, with US Food and Drug Administration approval of multiple targeted agents, such as V-Raf murine sarcoma viral oncogene homolog B1/mitogen-activated protein kinase kinase inhibitors and multiple immunotherapy agents, such as cytotoxic T lymphocyte-associated protein 4 and anti-programmed cell death protein 1/ligand 1 blockade. Based on insight into the respective advantages of the above two strategies, the present article provided a review of clinical trials of the application of targeted therapy and immunotherapy, as well as novel approaches of their combinations for the treatment of metastatic melanoma in recent years, with a focus on upcoming initiatives to improve the efficacy of these treatment approaches for metastatic melanoma.

Immunotherapy in Melanoma: Recent Advancements and Future Directions

Immune checkpoint inhibition has fundamentally altered the treatment paradigm of resectable and unresectable melanoma, resulting in dramatic improvements in patient outcomes. With these advances, the five-year overall survival in patients with newly diagnosed unresectable disease has eclipsed 50%. Ongoing research is focused on improving outcomes further, with a considerable emphasis on preventing de novo and acquired resistance and personalizing therapeutic options. Here, we review the ongoing advancements in the treatment of malignant melanoma, focusing on novel combination strategies that aim to build upon the successes of the last decade.

Efficacy and safety of bevacizumab in patients with malignant melanoma: a systematic review and PRISMA-compliant meta-analysis of randomized controlled trials and non-comparative clinical studies

Background: Malignant melanoma is a highly aggressive cancer that spreads and metastasizes quickly. In recent years, the antiangiogenic drug bevacizumab has been trialed to treat malignant melanoma. We conducted the first meta-analysis to examine the efficacy and safety of bevacizumab combined with other drugs in malignant melanoma. Methods: We searched for randomized controlled trials (RCTs) and non-comparative clinical studies of bevacizumab combined with chemotherapy, targeted medicine, and interferon to treat malignant melanoma in PubMed, Embase, the Cochrane Library, and Web of Science. Meta-analysis of RCT was performed using Review Manager (version 5.4), and non-comparative meta-analysis was performed using R (version 4.0.3). The primary outcome was the objective response rate. Depending on the heterogeneity of the included studies, the pooled outcomes and 95% CI were calculated using either random-effects or fixed-effect models. Subgroup outcomes were calculated with possible relevant variables. Sensitivity analyses were carried out by excluding each study from the highly heterogeneous pooled results in turn. Funnel plot and Begg's test were used to test the included studies' potential publication bias. The level of significance was set at p < 0.05. Results: This meta-analysis included 20 trials: five RCTs and 15 non-comparative clinical studies with a total of 23 bevacizumab intervention arms. In 14 treatment arms, bevacizumab was combined with chemotherapy drugs such as fotemustine, dacarbazine, carboplatin/paclitaxel, and temozolomide. In six treatment arms, bevacizumab was combined with targeted medicines such as imatinib, everolimus, sorafenib, erlotinib, and temsirolimus. There were also six treatment arms that used bevacizumab in combination with interferon. The pooled objective response rate was 15.8% (95% CI, 11.4%-20.2%). Bevacizumab plus carboplatin/paclitaxel significantly increased the overall survival compared to carboplatin/paclitaxel (HR = 0.64, 95% CI, 0.49-0.85, p < 0.01). Fatigue, nausea, leukopenia, thrombocytopenia, and neutropenia were the most common adverse events. The pooled incidence of hypertension of all bevacizumab arms in malignant melanoma was 32.4% (95% CI, 24.5%-40.3%). Conclusion: This study showed that bevacizumab combined with chemotherapy might be effective and well-tolerated in patients with stage III or IV unresectable malignant melanoma. Systematic Review Registration: [https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=304625], identifier [CRD42022304625].

Colorectal cancer liver metastasis: genomic evolution and crosstalk with the liver microenvironment

Colorectal cancer (CRC) patients frequently develop liver metastases, which are the major cause of cancer-related mortality. The molecular basis and management of colorectal liver metastases (CRLMs) remain a challenging clinical issue. Recent genomic evidence has demonstrated the liver tropism of CRC and the presence of a stricter evolutionary bottleneck in the liver as a target organ compared to lymph nodes. This bottleneck challenging CRC cells in the liver is organ-specific and requires adaptation not only at the genetic level, but also at the phenotypic level to crosstalk with the hepatic microenvironment. Here, we highlight the emerging evidence on the clonal evolution of CRLM and review recent insights into the molecular mechanisms orchestrating the bidirectional interactions between metastatic CRC cells and the unique liver microenvironment.

Recent advancements in the B7/CD28 immune checkpoint families: new biology and clinical therapeutic strategies

The B7/CD28 families of immune checkpoints play vital roles in negatively or positively regulating immune cells in homeostasis and various diseases. Recent basic and clinical studies have revealed novel biology of the B7/CD28 families and new therapeutics for cancer therapy. In this review, we discuss the newly discovered KIR3DL3/TMIGD2/HHLA2 pathways, PD-1/PD-L1 and B7-H3 as metabolic regulators, the glycobiology of PD-1/PD-L1, B7x (B7-H4) and B7-H3, and the recently characterized PD-L1/B7-1 cis-interaction. We also cover the tumor-intrinsic and -extrinsic resistance mechanisms to current anti-PD-1/PD-L1 and anti-CTLA-4 immunotherapies in clinical settings. Finally, we review new immunotherapies targeting B7-H3, B7x, PD-1/PD-L1, and CTLA-4 in current clinical trials.

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

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

Improvement strategy for immune checkpoint blockade: A focus on the combination with immunogenic cell death inducers

Cancer immunotherapies have yielded promising outcomes in various malignant tumors by blocking specific immune checkpoint molecules, such as programmed cell death 1 and cytotoxic T lymphocyte antigen 4. However, only a few patients respond to immune checkpoint blockade therapy because of the poor immunogenicity of tumor cells and immune-suppressive tumor microenvironment. Accumulating evidence suggests that chemotherapeutic agents, including oxaliplatin and doxorubicin, not only mediate direct cytotoxicity in tumor cells but also induce immunogenic cancer cell death to stimulate a powerful anti-cancer immune response in the tumor microenvironment. In this review, we summarize the recent advances in cancer combination therapy based on immune checkpoint inhibitors plus immunogenic cell death inducers. Despite some clinical failures and challenges, immunogenic cell death inducers have displayed great potential when combined with immune checkpoint inhibitors for anti-cancer treatment in both preclinical studies and clinical trials.

Novel technologies for applying immune checkpoint blockers

Cancer cells develop several ways to subdue the immune system among others via upregulation of inhibitory immune checkpoint (ICP) proteins. These ICPs paralyze immune effector cells and thereby enable unfettered tumor growth. Monoclonal antibodies (mAbs) that block ICPs can prevent immune exhaustion. Due to their outstanding effects, mAbs revolutionized the field of cancer immunotherapy. However, current ICP therapy regimens suffer from issues related to systemic administration of mAbs, including the onset of immune related adverse events, poor pharmacokinetics, limited tumor accessibility and immunogenicity. These drawbacks and new insights on spatiality prompted the exploration of novel administration routes for mAbs for instance peritumoral delivery. Moreover, novel ICP drug classes that are adept to novel delivery technologies were developed to circumvent the drawbacks of mAbs. We therefore review the state-of-the-art and novel delivery strategies of ICP drugs.

Circulating galectin-1 delineates response to bevacizumab in melanoma patients and reprograms endothelial cell biology

Blockade of vascular endothelial growth factor (VEGF) signaling with bevacizumab, a humanized anti-VEGF monoclonal antibody (mAb), or with receptor tyrosine kinase inhibitors, has improved progression-free survival and, in some indications, overall survival across several types of cancers by interrupting tumor angiogenesis. However, the clinical benefit conferred by these therapies is variable, and tumors from treated patients eventually reinitiate growth. Previously we demonstrated, in mouse tumor models, that galectin-1 (Gal1), an endogenous glycan-binding protein, preserves angiogenesis in anti-VEGF-resistant tumors by co-opting the VEGF receptor (VEGFR)2 signaling pathway in the absence of VEGF. However, the relevance of these findings in clinical settings is uncertain. Here, we explored, in a cohort of melanoma patients from AVAST-M, a multicenter, open-label, randomized controlled phase 3 trial of adjuvant bevacizumab versus standard surveillance, the role of circulating plasma Gal1 as part of a compensatory mechanism that orchestrates endothelial cell programs in bevacizumab-treated melanoma patients. We found that increasing Gal1 levels over time in patients in the bevacizumab arm, but not in the observation arm, significantly increased their risks of recurrence and death. Remarkably, plasma Gal1 was functionally active as it was able to reprogram endothelial cell biology, promoting migration, tubulogenesis, and VEGFR2 phosphorylation. These effects were prevented by blockade of Gal1 using a newly developed fully human anti-Gal1 neutralizing mAb. Thus, using samples from a large-scale clinical trial from stage II and III melanoma patients, we validated the clinical relevance of Gal1 as a potential mechanism of resistance to bevacizumab treatment.

Identification of a prognostic six-immune-gene signature and a nomogram model for uveal melanoma

BACKGROUND

To identify an immune-related prognostic signature and find potential therapeutic targets for uveal melanoma.

METHODS

The RNA-sequencing data obtained from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) datasets. The prognostic six-immune-gene signature was constructed through least absolute shrinkage and selection operator and multi-variate Cox regression analyses. Functional enrichment analysis and single sample GSEA were carried out. In addition, a nomogram model established by integrating clinical variables and this signature risk score was also constructed and evaluated.

RESULTS

We obtained 130 prognostic immune genes, and six of them were selected to construct a prognostic signature in the TCGA uveal melanoma dataset. Patients were classified into high-risk and low-risk groups according to a median risk score of this signature. High-risk group patients had poorer overall survival in comparison to the patients in the low-risk group (p < 0.001). These findings were further validated in two external GEO datasets. A nomogram model proved to be a good classifier for uveal melanoma by combining this signature. Both functional enrichment analysis and single sample GSEA analysis verified that this signature was truly correlated with immune system. In addition, in vitro cell experiments results demonstrated the consistent trend of our computational findings.

CONCLUSION

Our newly identified six-immune-gene signature and a nomogram model could be used as meaningful prognostic biomarkers, which might provide uveal melanoma patients with individualized clinical prognosis prediction and potential novel treatment targets.

Immune microenvironment of cholangiocarcinoma: Biological concepts and treatment strategies

Cholangiocarcinoma is characterized by a poor prognosis with limited treatment and management options. Chemotherapy using gemcitabine with cisplatin is the only available first-line therapy for patients with advanced cholangiocarcinoma, although it offers only palliation and yields a median survival of < 1 year. Recently there has been a resurgence of immunotherapy studies focusing on the ability of immunotherapy to inhibit cancer growth by impacting the tumor microenvironment. Based on the TOPAZ-1 trial, the US Food and Drug Administration has approved the combination of durvalumab and gemcitabine with cisplatin as the first-line treatment of cholangiocarcinoma. However, immunotherapy, like immune checkpoint blockade, is less effective in cholangiocarcinoma than in other types of cancer. Although several factors such as the exuberant desmoplastic reaction are responsible for cholangiocarcinoma treatment resistance, existing literature on cholangiocarcinoma cites the inflammatory and immunosuppressive environment as the most common factor. However, mechanisms activating the immunosuppressive tumor microenvironment contributing to cholangiocarcinoma drug resistance are complicated. Therefore, gaining insight into the interplay between immune cells and cholangiocarcinoma cells, as well as the natural development and evolution of the immune tumor microenvironment, would provide targets for therapeutic intervention and improve therapeutic efficacy by developing multimodal and multiagent immunotherapeutic approaches of cholangiocarcinoma to overcome the immunosuppressive tumor microenvironment. In this review, we discuss the role of the inflammatory microenvironment-cholangiocarcinoma crosstalk and reinforce the importance of inflammatory cells in the tumor microenvironment, thereby highlighting the explanatory and therapeutic shortcomings of immunotherapy monotherapy and proposing potentially promising combinational immunotherapeutic strategies.

Genetic Alterations of Melanoma Brain Metastases: A Systematic Review and Meta-Analysis

BACKGROUND

Data on molecular alterations harbored by melanoma brain metastases (MBMs) are limited, and this has hampered the development of more effective therapeutic strategies. We conducted a systematic review and meta-analysis of all the studies reporting DNA sequencing data of MBMs, in order to identify recurrently mutated genes and molecular pathways significantly enriched for genetic alterations.

METHODS

We searched PubMed, Embase and Scopus for articles published from the inception of each database to June 30, 2021. We included in the analysis all the studies that reported individual patient data on DNA sequencing of MBMs, assessing single nucleotide variants (SNVs) and/or gene copy number variations (CNVs) in at least five tumor samples. Meta-analysis was performed for genes evaluated for SNVs and/or CNVs in at least two studies. Pooled proportions of samples with SNVs and/or CNVs was calculated by applying random-effect models based on the DerSimonian-Laird method. Gene-set enrichment analysis (GSEA) was performed to identify molecular pathways significantly enriched for mutated genes.

RESULTS

Ten studies fulfilled the inclusion criteria and were included in the analysis, for a total of 531 samples of MBMs evaluated. Twenty-seven genes were found recurrently mutated with a meta-analytic rate of SNVs higher than 5%. GSEA conducted on the list of these 27 recurrently mutated genes revealed vascular endothelial growth factor-activated receptor activity and transmembrane receptor protein tyrosine kinase activity to be among the top 10 gene ontology (GO) molecular functions significantly enriched for mutated genes, while regulation of apoptosis and cell proliferation were among the top 10 significantly enriched GO biological processes. Notably, a high meta-analytic rate of SNVs was found in several actionable cancer-associated genes, such as all the vascular endothelial growth factor (VEGF) receptor isoforms (i.e., Flt1 and Flt2 genes, for both SNV rate: 0.22, 95% CI 0.04-0.49; KDR gene, SNV rate: 0.1, 95% CI 0.05-0.16). Finally, two tumor suppressor genes were characterized by a high meta-analytic rate of CNVs: CDKN2A/B (CNV rate: 0.59, 95% CI 0.23-0.90) and PTEN (CNV rate: 0.31, 95% CI 0.02-0.95).

CONCLUSION

MBMs harbored actionable molecular alterations that could be exploited as therapeutic targets to improve the poor prognosis of patients.

Lenvatinib Might Induce Activation of Host Immunity in Patients with Hepatocellular Carcinoma

INTRODUCTION

Atezolizumab, an immune checkpoint inhibitor, plus bevacizumab, a monoclonal antibody that binds to vascular endothelial growth factor (VEGF), is an approved first-line systemic treatment for unresectable hepatocellular carcinoma (HCC). Immune checkpoint inhibitors are more effective in patients with HCC when administered with anti-VEGF drugs; however, these drugs affect host immunity. Lenvatinib is an anti-VEGF agent used to treat HCC; therefore, this study evaluated the effect of treatment of HCC with lenvatinib on host immunity in patients with chronic liver disease (CLD).

METHODS

We studied adult Japanese patients with CLD and unresectable HCC treated with lenvatinib at our hospital. Lenvatinib was administered for 4 weeks (8 mg/day for bodyweight <60 kg; 12 mg/day for bodyweight >60 kg). Blood samples were collected at baseline and at 4 weeks of treatment and examined for immune-related changes.

RESULTS

Forty-three patients were enrolled in this study. We found a significant increase in T helper (Th) 1 cells following 4 weeks of lenvatinib treatment, although there was no significant difference in Th2 cells and regulatory T cells. We also found a significant increase in serum levels of TNF-alpha, soluble TNF-alpha receptor I, and endothelial growth factor following 4 weeks of lenvatinib treatment. Furthermore, an increase in Th1 cells and serum levels of TNF-alpha was found in patients with partial response.

CONCLUSION

Lenvatinib might induce Th1-dominant host immunity in patients with CLD and unresectable HCC treatment in patients who showed a partial response. These changes in host immunity may be a biomarker in HCC patients treated with lenvatinib.

The role of angiogenesis in melanoma: Clinical treatments and future expectations

The incidence of melanoma has increased rapidly over the past few decades, with mortality accounting for more than 75% of all skin cancers. The high metastatic potential of Melanoma is an essential factor in its high mortality. Vascular angiogenic system has been proved to be crucial for the metastasis of melanoma. An in-depth understanding of angiogenesis will be of great benefit to melanoma treatment and may promote the development of melanoma therapies. This review summarizes the recent advances and challenges of anti-angiogenic agents, including monoclonal antibodies, tyrosine kinase inhibitors, human recombinant Endostatin, and traditional Chinese herbal medicine. We hope to provide a better understanding of the mechanisms, clinical research progress, and future research directions of melanoma.

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

Introduction

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

Case presentation

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

Conclusion

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

Low-dose anti-VEGFR2 therapy promotes anti-tumor immunity in lung adenocarcinoma by down-regulating the expression of layilin on tumor-infiltrating CD8(+)T cells

PURPOSE

Our study intended to explore how low-dose anti-angiogenic drugs affected anti-tumor immunity of tumor-infiltrating exhausted CD8⁺T cells and achieved better clinical response when combined with immunotherapy. We set out to find potential targets or predictive biomarker on CD8⁺T cells for immunotherapy.

METHODS

We tested different doses of anti-VEGFR2 antibody combined with anti-PD1 antibody to treat LUAD in vivo and analyzed tumor-infiltrating CD8⁺T cells by flow cytometry. CD8⁺T cells overexpressing LAYN were co-cultured with LA795 cell lines to identify the function of LAYN in CD8⁺T cells. We also analyzed clinical samples from advanced LUAD patients treated with anti-angiogenesis therapy combined with immunotherapy.

RESULTS

Low-dose anti-VEGFR2 antibody combined with anti-PD1 antibody treatment delayed tumor growth and prolonged the survival time of tumor-bearing mice. The number of tumor-infiltrating CD8⁺T cells was reduced and the expression of LAYN was down-regulated in tumor-infiltrating CD8⁺T cells in the low-dose anti-VEGFR2 combination group. It was found that LAYN inhibited the killing function of CD8⁺T cells. In patients with advanced LUAD who received anti-angiogenesis therapy combined with immunotherapy, the LAYN⁺CD8⁺T cell subpopulation in good responders was significantly higher than that in poor responders. Furthermore, we demonstrated the expression of LAYN was regulated by upstream transcription factor NR4A1.

CONCLUSION

Low-dose anti-VEGFR2 antibody combined with anti-PD1 antibody therapy promoted anti-tumor immunity and the downregulation of LAYN in tumor-infiltrating CD8⁺T cells played an important role in this process. These findings had implications for improving the efficacy of immune checkpoint blockade therapy and further optimized clinical treatment guidelines in advanced LUAD.

Emerging Insights on Immunotherapy in Liver Cancer

Significance: Hepatocellular carcinoma (HCC) is a liver malignancy with high mortality rate, limited treatment options, and poor prognosis. Sorafenib has been the only systemic treatment option for patients with advanced HCC for more than a decade. HCC is a typical inflammation-related tumor with a distinct immunosuppressive microenvironment especially the upregulation of immune checkpoints. Recent Advances: Immunotherapy has shown persistent and powerful efficacy in HCC treatment. Several preclinical and clinical studies have prompted the application of immunotherapy in first-line, second-line, and postline treatment of HCC, which has profoundly shifted the paradigm for advanced HCC treatment in the past few years. Critical Issues and Future Directions: Major unaddressed challenges in HCC immunotherapy include the discovery and validation of biological markers that predict the efficacy, the application of immunotherapy in patients with impaired liver function and nonalcoholic steatohepatitis-associated HCC, and the exploration of immunotherapy combinations with better effectiveness. This review provides the latest advances in the research of immune microenvironment and immunotherapy in HCC. Antioxid. Redox Signal. 37, 1325-1338.

Atezolizumab plus Bevacizumab in Patients with Unresectable or Metastatic Mucosal Melanoma: A Multicenter, Open-Label, Single-Arm Phase II Study

PURPOSE

Anti-programmed cell death-1 monotherapy is part of standard therapy for cutaneous melanoma but has low efficacy in mucosal melanoma. We evaluated the efficacy and safety of atezolizumab plus bevacizumab as first-line therapy for advanced mucosal melanoma.

PATIENTS AND METHODS

This multicenter, open-label, single-arm, phase II study used a Simon's two-stage design. Atezolizumab (fixed-dose, 1,200 mg) and bevacizumab (7.5 mg/kg) were administered by intravenous infusion every 3 weeks. The primary endpoint was objective response rate (ORR), determined per RECIST v1.1. Secondary endpoints included progression-free survival (PFS), overall survival (OS), duration of response (DOR), and safety, with adverse events (AE) summarized using NCI-CTCAE v5.0.

RESULTS

Overall, 43 patients were enrolled, including 20 (46.5%) with unresectable and 23 (53.5%) with metastatic mucosal melanoma. Median follow-up was 13.4 months at data cutoff (July 30, 2021). Forty patients were evaluable for response: ORR was 45.0% [95% confidence interval (CI), 29.3%-61.5%; one complete response, 17 partial responses]. Median PFS was 8.2 months (95% CI, 2.7-9.6); 6- and 12-month PFS rates were 53.4% (95% CI, 36.6%-67.6%) and 28.1% (95% CI, 14.2%-43.9%), respectively. Median OS was not reached (NR; 95% CI, 14.4-NR). Six- and 12-month OS rates were 92.5% (95% CI, 78.5%-97.5%) and 76.0% (95% CI, 57.1%-87.5%), respectively. Median DOR was 12.5 months (95% CI, 5.5-NR). Overall, 90.7% (39/43) of patients experienced treatment-related AEs; 25.6% (11/43) experienced grade ≥3 events.

CONCLUSIONS

Atezolizumab in combination with bevacizumab showed promising efficacy and manageable safety in patients with advanced mucosal melanoma.

Cancer cell autophagy, reprogrammed macrophages, and remodeled vasculature in glioblastoma triggers tumor immunity

Glioblastoma (GBM) is poorly responsive to therapy and invariably lethal. One conceivable strategy to circumvent this intractability is to co-target distinctive mechanistic components of the disease, aiming to concomitantly disrupt multiple capabilities required for tumor progression and therapeutic resistance. We assessed this concept by combining vascular endothelial growth factor (VEGF) pathway inhibitors that remodel the tumor vasculature with the tricyclic antidepressant imipramine, which enhances autophagy in GBM cancer cells and unexpectedly reprograms immunosuppressive tumor-associated macrophages via inhibition of histamine receptor signaling to become immunostimulatory. While neither drug is efficacious as monotherapy, the combination of imipramine with VEGF pathway inhibitors orchestrates the infiltration and activation of CD8 and CD4 T cells, producing significant therapeutic benefit in several GBM mouse models. Inclusion up front of immune-checkpoint blockade with anti-programmed death-ligand 1 (PD-L1) in eventually relapsing tumors markedly extends survival benefit. The results illustrate the potential of mechanism-guided therapeutic co-targeting of disparate biological vulnerabilities in the tumor microenvironment.

Cancer Resistance to Immunotherapy: Molecular Mechanisms and Tackling Strategies

Cancer immunotherapy has fundamentally altered cancer treatment; however, its efficacy is limited to a subset of patients in most clinical settings. The immune system plays a key role in cancer progression from tumor initiation to the metastatic state. Throughout the treatment course, communications between the immune cells in the tumor microenvironment and the immune macroenvironment, as well as interactions between the immune system and cancer cells, are dynamic and constantly evolving. To improve the clinical benefit for patients who do not respond completely to immunotherapy, the molecular mechanisms of resistance to immunotherapy must be elucidated in order to develop effective strategies to overcome resistance. In an attempt to improve and update the current understanding of the molecular mechanisms that hinder immunotherapy, we discuss the molecular mechanisms of cancer resistance to immunotherapy and the available treatment strategies.

GD2-targeting CAR-T cells enhanced by transgenic IL-15 expression are an effective and clinically feasible therapy for glioblastoma

Background

Aggressive primary brain tumors such as glioblastoma are uniquely challenging to treat. The intracranial location poses barriers to therapy, and the potential for severe toxicity. Effective treatments for primary brain tumors are limited, and 5-year survival rates remain poor. Immune checkpoint inhibitor therapy has transformed treatment of some other cancers but has yet to significantly benefit patients with glioblastoma. Early phase trials of chimeric antigen receptor (CAR) T-cell therapy in patients with glioblastoma have demonstrated that this approach is safe and feasible, but with limited evidence of its effectiveness. The choices of appropriate target antigens for CAR-T-cell therapy also remain limited.

Methods

We profiled an extensive biobank of patients’ biopsy tissues and patient-derived early passage glioma neural stem cell lines for GD2 expression using immunomicroscopy and flow cytometry. We then employed an approved clinical manufacturing process to make CAR- T cells from patients with peripheral blood of glioblastoma and diffuse midline glioma and characterized their phenotype and function in vitro. Finally, we tested intravenously administered CAR-T cells in an aggressive intracranial xenograft model of glioblastoma and used multicolor flow cytometry, multicolor whole-tissue immunofluorescence and next-generation RNA sequencing to uncover markers associated with effective tumor control.

Results

Here we show that the tumor-associated antigen GD2 is highly and consistently expressed in primary glioblastoma tissue removed at surgery. Moreover, despite patients with glioblastoma having perturbations in their immune system, highly functional GD2-specific CAR-T cells can be produced from their peripheral T cells using an approved clinical manufacturing process. Finally, after intravenous administration, GD2-CAR-T cells effectively infiltrated the brain and controlled tumor growth in an aggressive orthotopic xenograft model of glioblastoma. Tumor control was further improved using CAR-T cells manufactured with a clinical retroviral vector encoding an interleukin-15 transgene alongside the GD2-specific CAR. These CAR-T cells achieved a striking 50% complete response rate by bioluminescence imaging in established intracranial tumors.

Conclusions

Targeting GD2 using a clinically deployed CAR-T-cell therapy has a sound scientific and clinical rationale as a treatment for glioblastoma and other aggressive primary brain tumors.

Prognostic significance of programmed death-1 and programmed death ligand-1 proteins in breast cancer

In numerous studies related to tumor prognosis, programmed death-ligand 1 (PD-L1) has been identified as a biomarker. This work aimed to determine the prognostic importance of PD-L1 in breast cancer. We searched electronic databases such as PubMed, Google scholar, home pages of publishing groups, medical, clinical, and pharmaceutical sciences journals, as well as other relevant sources to discover the importance of PD-1 and PD-L1 expression in breast cancer therapies and also recurrence. The keywords used in this search were autoimmunity, programmed cell death, PD-L1 or PD-1, and breast cancer. Our inclusion criteria included studies showing the synergy between the expression of PD-L1 and PD-1 in primary breast cancers as prognostic markers and this research was limited to humans only. We included review articles, original research, letters to the editor, case reports, and short communications in our study, published in English. We focused our work on PD-L1 mRNA expression in breast cancer cell lines. PD-L1 expression has been decisively demonstrated to be a high-risk factor for breast cancer with a bad prognosis.

Treatment of Metastatic Melanoma with a Combination of Immunotherapies and Molecularly Targeted Therapies

Simple Summary

Immunotherapies and molecularly targeted therapies have drastically changed the therapeutic approach for unresectable advanced or metastatic melanoma. The majority of melanoma patients have benefitted from these therapies; however, some patients acquire resistance to them. Novel combinations of immunotherapies and molecularly targeted therapies may be more efficient in treating these patients. In this review, we discuss various combination therapies under pre-clinical and clinical development which can reduce toxicity, enhance efficacy, and prevent recurrences in patients with metastatic melanoma.

Abstract

Melanoma possesses invasive metastatic growth patterns and is one of the most aggressive types of skin cancer. In 2021, it is estimated that 7180 deaths were attributed to melanoma in the United States alone. Once melanoma metastasizes, traditional therapies are no longer effective. Instead, immunotherapies, such as ipilimumab, pembrolizumab, and nivolumab, are the treatment options for malignant melanoma. Several biomarkers involved in tumorigenesis have been identified as potential targets for molecularly targeted melanoma therapy, such as tyrosine kinase inhibitors (TKIs). Unfortunately, melanoma quickly acquires resistance to these molecularly targeted therapies. To bypass resistance, combination treatment with immunotherapies and single or multiple TKIs have been employed and have been shown to improve the prognosis of melanoma patients compared to monotherapy. This review discusses several combination therapies that target melanoma biomarkers, such as BRAF, MEK, RAS, c-KIT, VEGFR, c-MET and PI3K. Several of these regimens are already FDA-approved for treating metastatic melanoma, while others are still in clinical trials. Continued research into the causes of resistance and factors influencing the efficacy of these combination treatments, such as specific mutations in oncogenic proteins, may further improve the effectiveness of combination therapies, providing a better prognosis for melanoma patients.

Inflammatory Thoracic Aortic Aneurysm in a Patient with Advanced Lung Adenocarcinoma Treated with Pembrolizumab

A 57-year-old man with lung adenocarcinoma was treated with chemotherapy and immune checkpoint blockade. After two cycles of carboplatin, pemetrexed, and pembrolizumab, he developed a persistent fever. Chest computed tomography (CT) suggested inflammation of the aortic wall. We treated the patient with corticosteroids. After four cycles of carboplatin, pemetrexed, and pembrolizumab, chest CT showed an aneurysm in the ascending aorta. We diagnosed him with inflammatory thoracic aortic aneurysm induced by pembrolizumab and performed surgical replacement of the ascending aorta. Although this might be a very rare case, we should be aware of aortitis as a potential adverse effect of pembrolizumab.

Treatment with a VEGFR-2 antibody results in intra-tumor immune modulation and enhances anti-tumor efficacy of PD-L1 blockade in syngeneic murine tumor models

Prolonged activation of vascular endothelial growth factor receptor-2 (VEGFR-2) due to mis-regulation of the VEGF pathway induces aberrant blood vessel expansion, which supports growth and survival of solid tumors. Therapeutic interventions that inhibit the VEGFR-2 pathway have therefore become a mainstay of cancer treatment. Non-clinical studies have recently revealed that blockade of angiogenesis can modulate the tumor microenvironment and enhance the efficacy of concurrent immune therapies. Ramucirumab is an FDA-approved anti-angiogenic antibody that inhibits VEGFR-2 and is currently being evaluated in clinical studies in combination with anti-programmed cell death (PD-1) axis checkpoint inhibitors (pembrolizumab, durvalumab, or sintilimab) across several cancer types. The purpose of this study is to establish a mechanistic basis for the enhanced activity observed in the combined blockade of VEGFR-2 and PD-1-axis pathways. Pre-clinical studies were conducted in murine tumor models known to be responsive to anti-PD-1 axis therapy, using monoclonal antibodies that block mouse VEGFR-2 and programmed death-ligand 1 (PD-L1). Combination therapy resulted in enhanced anti-tumor activity compared to anti-PD-L1 monotherapy. VEGFR-2 blockade at early timepoints post-anti-PD-L1 therapy resulted in a dose-dependent and transient enhanced infiltration of T cells, and establishment of immunological memory. VEGFR-2 blockade at later timepoints resulted in enhancement of anti-PD-L1-driven immune cell infiltration. VEGFR-2 and PD-L1 monotherapies induced both unique and overlapping patterns of immune gene expression, and combination therapy resulted in an enhanced immune activation signature. Collectively, these results provide new and actionable insights into the mechanisms by which concurrent VEGFR-2 and PD-L1 antibody therapy leads to enhanced anti-tumor efficacy.

The Multi-Kinase Inhibitor Lucitanib Enhances the Antitumor Activity of Coinhibitory and Costimulatory Immune Pathway Modulators in Syngeneic Models

Lucitanib is a multi-tyrosine kinase inhibitor whose targets are associated with angiogenesis and other key cancer and immune pathways. Its antiangiogenic properties are understood, but lucitanib's immunomodulatory activity is heretofore unknown. Lucitanib exhibited such activity in vivo, increasing CD3+, CD8+, and CD4+ T cells and decreasing dendritic cells and monocyte-derived suppressor cells in mouse spleens. Depletion of CD8+ T cells from syngeneic MC38 colon tumor-bearing mice reduced the antitumor efficacy of lucitanib and revealed a CD8+ T-cell-dependent component of lucitanib's activity. The combination of lucitanib and costimulatory immune pathway agonists targeting 4-1BB, glucocorticoid-induced TNFR (GITR), inducible T-cell co-stimulator (ICOS), or OX40 exhibited enhanced antitumor activity compared with each single agent in immunocompetent tumor models. Lucitanib combined with blockade of cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) or programmed cell death protein-1 (PD-1) coinhibitory immune pathways also showed enhanced antitumor activity over the single agents in multiple models. In CT26 tumors, lucitanib, alone or combined with anti-PD-1, reduced CD31+ vessels and depleted F4/80+ macrophages. Combination treatment also increased the number of intratumoral T cells. Gene expression in pathways associated with immune activity was upregulated by lucitanib in MC38 tumors and further potentiated by combination with anti-PD-1. Accordingly, lucitanib, alone or combined with anti-PD-1, increased intratumoral CD8+ T-cell abundance. Lucitanib's antitumor and pharmacodynamic activity, alone or combined with anti-PD-1, was not recapitulated by specific vascular endothelial growth factor receptor-2 (VEGFR2) inhibition. These data indicate that lucitanib can modulate vascular and immune components of the tumor microenvironment and cooperate with immunotherapy to enhance antitumor efficacy. They support the clinical development of lucitanib combined with immune pathway modulators to treat cancer.

Apatinib: A Novel Antiangiogenic Drug in Monotherapy or Combination Immunotherapy for Digestive System Malignancies

Digestive system malignancies are one of the primary causes of cancer-related death. Meanwhile, angiogenesis has been proved to play an important role in the process of cancer neovascularization. Apatinib, a novel targeted antiangiogenic molecule, could generate highly selective competition in the vascular endothelial growth factor receptor-2, involved in tumor progression and metastasis. It has been implied as a promising cancer treatment agent that can prevent tumor cell proliferation meanwhile inhibit tumor angiogenesis. Furthermore, completed clinical trials demonstrated that apatinib could prolong the progression-free survival and overall survival in advanced gastric cancer and primary liver cancer. Recent studies revealed that apatinib had a synergistic effect with immunotherapy as a second-line and third-line treatment regimen for some other cancers. In this review, we summarize the pharmacological properties of apatinib and the latest clinical application in chemotherapy-refractory patients with advanced digestive system cancer. Based on the comparable survival results, the molecular mechanisms of apatinib are prospective to include the antiangiogenic, apoptosis-inducing, and autophagy-inducing properties in the corresponding signaling pathway. Treatment of apatinib monotherapy or combination immunotherapy remains the optimal option for patients with digestive system malignancies in the future.

Normalization of tumor vasculature: A potential strategy to increase the efficiency of immune checkpoint blockades in cancers

Immune checkpoint inhibitors (ICIs) eliminate tumor cells by reactivating CD8 + T cells using the cytotoxic effects of the immune system. However, in this process, tumor angiogenic factors and abnormal formation of tumor blood vessels are not conducive to the treatment of ICIs. In the tumor microenvironment (TME), proangiogenic factors prevent dendritic cell maturation, reduce T cell infiltration, and recruit inhibitory immune cells such as regulatory T (Treg) cells. Abnormal tumor blood vessels also prevent immune cells and chemotherapy drugs from reaching the target effectively and lead to poor perfusion and severe hypoxia of the tumor. Treatment with antiangiogenic inhibitors can block the transmission of abnormal angiogenesis signals and promote the normalization of tumor vasculature. Therefore, the combination of antiangiogenic inhibitors and ICIs is used in clinical therapy. Combination therapy has been proven theoretically feasible in preclinical trials, and many clinical trials have been completed to confirm its safety and efficacy.

Circulating Immune Cell and Outcome Analysis from the Phase II Study of PD-L1 Blockade with Durvalumab for Newly Diagnosed and Recurrent Glioblastoma

PURPOSE

PD-L1 is upregulated in glioblastoma and supports immunosuppression. We evaluated PD-L1 blockade with durvalumab among glioblastoma cohorts and investigated potential biomarkers.

PATIENTS AND METHODS

MGMT unmethylated newly diagnosed patients received radiotherapy plus durvalumab (cohort A; n = 40). Bevacizumab-naïve, recurrent patients received durvalumab alone (cohort B; n = 31) or in combination with standard bevacizumab (cohort B2; n = 33) or low-dose bevacizumab (cohort B3; n = 33). Bevacizumab-refractory patients received durvalumab plus bevacizumab (cohort C; n = 22). Primary endpoints were: OS-12 (A), PFS-6 (B, B2, B3), and OS-6 (C). Exploratory biomarkers included: a systematic, quantitative, and phenotypic evaluation of circulating immune cells; tumor mutational burden (TMB); and tumor immune activation signature (IAS).

RESULTS

No cohort achieved the primary efficacy endpoint. Outcome was comparable among recurrent, bevacizumab-naïve cohorts. No unexpected toxicities were observed. A widespread reduction of effector immune cell subsets was noted among recurrent patients compared with newly diagnosed patients that was partially due to dexamethasone use. A trend of increased CD8+Ki67+ T cells at day 15 was noted among patients who achieved the primary endpoint and were not on dexamethasone. Neither TMB nor IAS predicted outcome.

CONCLUSIONS

Patients with recurrent glioblastoma have markedly lower baseline levels of multiple circulating immune cell subsets compared with newly diagnosed patients. An early increase in systemic Ki67+CD8+ cells may warrant further evaluation as a potential biomarker of therapeutic benefit among patients with glioblastoma undergoing checkpoint therapy. Dexamethasone decreased immune cell subsets. PD-L1 blockade and combination with standard or reduced dose bevacizumab was ineffective.

Double Trouble: Immunotherapy Doublets in Melanoma-Approved and Novel Combinations to Optimize Treatment in Advanced Melanoma

Immune checkpoint inhibitors, particularly anti-PD-1-based immune checkpoint inhibitors, have dramatically improved outcomes for patients with advanced melanoma and are currently deemed a standard of care. Ipilimumab/nivolumab is the first combination of immune checkpoint inhibitors to improve progression-free survival and overall survival in the first-line setting, with durable responses and the longest median overall survival, 72.1 months, of any drug therapy approved for advanced melanoma. However, its use is limited by the high rate of severe (grade 3-4) treatment-related adverse events. More recently, the novel immune checkpoint inhibitor combination of nivolumab/relatlimab (anti-PD-1/anti-LAG3) showed improved progression-free survival compared with nivolumab alone in the first-line setting and was well tolerated; thus, it is likely this combination will be added to the armamentarium as a first-line treatment for advanced melanoma. These changes in the treatment landscape have several treatment implications for decision-making. The choice of first-line systemic drug therapy, and the decision between immune checkpoint inhibitor monotherapy or combination therapy, requires a comprehensive assessment of disease-related factors and patient characteristics. Despite this striking progress, many patients' disease still progresses. Several new agents and therapeutic approaches are under investigation in clinical trials. Intralesional treatments hold promise for accessible metastases, although their broad application in the clinic will be limited. Prognostic and predictive biomarkers, as well as strategies to reduce treatment-related toxicities and overcome resistance, are required and are now the focus of clinical and translational research.

Cabozantinib Enhances Anti-PD1 Activity and Elicits a Neutrophil-Based Immune Response in Hepatocellular Carcinoma

PURPOSE

Immune checkpoint inhibitors combined with antiangiogenic agents produce benefits in the treatment of advanced hepatocellular carcinoma (HCC). We investigated the efficacy and immunomodulatory activity of cabozantinib alone and combined with anti-PD1 in experimental models of HCC, and explored the potential target population that might benefit from this combination.

EXPERIMENTAL DESIGN

C57BL/6J mice bearing subcutaneous Hepa1-6 or Hep53.4 tumors received cabozantinib, anti-PD1, their combination, or placebo. Tumor and blood samples were analyzed by flow cytometry, IHC, transcriptome, and cytokine profiling. Cabozantinib-related effects were validated in a colorectal cancer patient-derived xenograft model. Transcriptomic data from three human HCC cohorts (cohort 1: n = 167, cohort 2: n = 57, The Cancer Genome Atlas: n = 319) were used to cluster patients according to neutrophil features, and assess their impact on survival.

RESULTS

The combination of cabozantinib and anti-PD1 showed increased antitumor efficacy compared with monotherapy and placebo (P < 0.05). Cabozantinib alone significantly increased neutrophil infiltration and reduced intratumor CD8+PD1+ T-cell proportions, while the combination with anti-PD1 further stimulated both effects and significantly decreased regulatory T cell (Treg) infiltration (all P < 0.05). In blood, cabozantinib and especially combination increased the proportions of overall T cells (P < 0.01) and memory/effector T cells (P < 0.05), while lowering the neutrophil-to-lymphocyte ratio (P < 0.001 for combination). Unsupervised clustering of human HCCs revealed that high tumor enrichment in neutrophil features observed with the treatment combination was linked to less aggressive tumors with more differentiated and less proliferative phenotypes.

CONCLUSIONS

Cabozantinib in combination with anti-PD1 enhanced antitumor immunity by bringing together innate neutrophil-driven and adaptive immune responses, a mechanism of action which favors this approach for HCC treatment.

Blocking CD47 Shows Superior Anti-tumor Therapeutic Effects of Bevacizumab in Gastric Cancer

Background: Bevacizumab (Avastin^®), a humanized antiangiogenic monoclonal antibody, is widely used in the clinical treatment of tumour diseases. However, recent research has shown that the beneficial antiangiogenic effects of these agents have been limited in a number of patients due to complex immunosuppressive mechanisms. Here, we report a synergistic antitumour strategy through simultaneous blockade of VEGF and CD47 signalling to enhance the curative effect of advanced gastric cancer.

Method: A BGC-823 gastric tumour model was chosen to evaluate antitumour efficacy. Macrophage migration and phagocytosis were evaluated to determine immune-related resistance to bevacizumab therapy. Synergistic antitumour activity was observed on the basis of tumour volume, tumour weight, tumour inhibition rate, tumour angiogenesis and tumour metastasis when bevacizumab was combined with an anti-CD47 monoclonal antibody.

Results: Our study demonstrated that synergistic therapy targeting CD47 and VEGF reversed macrophage migration and phagocytosis, which were inhibited by antiangiogenic therapy and enhanced antitumour effects. Moreover, blockade of CD47 induced by antiangiogenic therapy inhibited tumour metastasis.

Conclusion: Our data provide an effective strategy to attenuate resistance to bevacizumab therapy, promoting clinical cancer treatment with antiangiogenic drugs in combination with CD47-targeting inhibitors.

Combined application of bevacizumab and PD-1 blockade displays durable treatment effects by increasing the infiltration and cytotoxic function of CD8+ T cells in lung cancer

Aim: VEGF/VEGFR inhibitors may help immune checkpoint inhibitors expand the population that will benefit from treatment. The authors investigated the efficacy of combined bevacizumab and PD-1 antibody. Materials & methods: C57BL/6J mice were injected subcutaneously with 1 × 10⁶ Lewis lung carcinoma cells. The mice were intraperitoneally injected with 0.25 mg anti-PD-1 inhibitors and/or 15 mg/kg bevacizumab. Tumor tissues were harvested. The authors reported that a non-small cell lung cancer patient received 200 mg PD-1 antibody combined with 7.5 mg/kg bevacizumab as fourth-line treatment. Results: Bevacizumab combined with PD-1 antibody induced a strong and durable antitumor effect. Bevacizumab combined with PD-1 antibody improved abnormal tumor vessels and enhanced the cytotoxic function and infiltration of T lymphocytes. The patient's survival time was significantly prolonged. Conclusion: Bevacizumab combined with anti-PD-1 antibody induces a durable antitumor effect by increasing the infiltration and cytotoxic function of CD8⁺ T cells in lung cancer.

PD-1 inhibitor in combination with fruquintinib therapy for initial unresectable colorectal cancer: A case report

BACKGROUND

PD-1 inhibitors in combination with fruquintinib have not previously been reported as neoadjuvant therapy for patients with colorectal cancer. In this case report, the combination of a PD-1 inhibitor and fruquintinib demonstrated good efficacy in patients with MSI-H colorectal cancer.

CASE SUMMARY

The patient was a young man in his 30s who had MSI-H type colon cancer. The patient underwent four cycles of neoadjuvant therapy with a PD-1 inhibitor combined with fruquintinib before surgery, resulting in regression of the mass and a successful surgery.

CONCLUSION

Some patients with colorectal cancer have the MSI-H type, and the first-line chemotherapy regimen is not effective. However, PD-1 monoclonal antibody immunotherapy has a good therapeutic effect, which can be improved by combination therapy with fruquintinib. We recommend that patients with a history of colon or rectal cancer receive universal MSI testing; then, neoadjuvant therapy should be used.