Immunotherapy for sarcomas: new frontiers and unveiled opportunities

B7-H3 is widely expressed in soft tissue sarcomas

PURPOSE

Targeted therapy development in soft tissue sarcoma (STS) has been burdened by the heterogeneity of this group of rare tumors. B7 homolog 3 protein (B7-H3) is a molecule in the same family as programmed death-ligand 1 (PD-L1). It has limited expression in noncancerous tissues and is overexpressed in many cancers, making it an attractive target for cancer therapy, and clinical trials targeting B7-H3 are actively underway. While available data demonstrate high expression levels of B7-H3 in individual sarcoma subtypes, its expression patterns across STS subtypes are not well described. The purpose of this study was to characterize the expression patterns of B7-H3 in STS.

PATIENTS AND METHODS

This retrospective analysis evaluated STS tumor specimens from patients with a variety of different subtypes. Specimens were evaluated by immunohistochemistry (IHC) for expression and staining pattern of B7-H3 both in tumors and in associated vasculature.

RESULTS

Specimens from 153 sarcoma patients included 15 different STS subtypes. B7-H3 was broadly expressed in 97% of samples (95% CI 0.93-0.99) and 69.2% demonstrated high levels of B7-H3 expression (95% CI 0.61-0.76). No significant association between B7-H3 positivity or expression level and prior treatment(s), tumor size, tumor grade, or patient age. B7-H3 positivity in vessels was found in 94.7% (145/153) of samples. In tumors that had been previously assessed for PD-L1 and PD-1, there was no correlation between B7-H3 positivity or expression and the positivity or expression level of PD-L1 or PD-1.

CONCLUSION

These data show high levels of B7-H3 positivity across soft tissue sarcoma subtypes, suggesting its feasibility as a therapeutic target for future sarcoma treatments. Future clinical trials are needed to evaluate whether targeting B7-H3 can provide clinical benefit to help patients with sarcoma.

Peripheral immune profiling of soft tissue sarcoma: perspectives for disease monitoring

Studying the tumor microenvironment and surrounding lymph nodes is the main focus of current immunological research on soft tissue sarcomas (STS). However, due to the restricted opportunity to examine tumor samples, alternative approaches are required to evaluate immune responses in non-surgical patients. Therefore, the purpose of this study was to evaluate the peripheral immune profile of STS patients, characterize patients accordingly and explore the impact of peripheral immunotypes on patient survival. Blood samples were collected from 55 STS patients and age-matched healthy donors (HD) controls. Deep immunophenotyping and gene expression analysis of whole blood was analyzed using multiparametric flow cytometry and real-time RT-qPCR, respectively. Using xMAP technology, proteomic analysis was also carried out on plasma samples. Unsupervised clustering analysis was used to classify patients based on their immune profiles to further analyze the impact of peripheral immunotypes on patient survival. Significant differences were found between STS patients and HD controls. It was found a contraction of B cells and CD4 T cells compartment, along with decreased expression levels of ICOSLG and CD40LG; a major contribution of suppressor factors, as increased frequency of M-MDSC and memory Tregs, increased expression levels of ARG1, and increased plasma levels of IL-10, soluble VISTA and soluble TIMD-4; and a compromised cytotoxic potential associated with NK and CD8 T cells, namely decreased frequency of CD56dim NK cells, and decreased levels of PRF1, GZMB, and KLRK1. In addition, the patients were classified into three peripheral immunotype groups: "immune-high," "immune-intermediate," and "immune-low." Furthermore, it was found a correlation between these immunotypes and patient survival. Patients classified as "immune-high" exhibited higher levels of immune-related factors linked to cytotoxic/effector activity and longer survival times, whereas patients classified as "immune-low" displayed higher levels of immune factors associated with immunosuppression and shorter survival times. In conclusion, it can be suggested that STS patients have a compromised systemic immunity, and the correlation between immunotypes and survival emphasizes the importance of studying peripheral blood samples in STS. Assessing the peripheral immune response holds promise as a useful method for monitoring and forecasting outcomes in STS.

The bispecific B7H3xCD3 antibody CC-3 induces T cell immunity against bone and soft tissue sarcomas

Sarcomas are rare and heterogeneous malignancies that are difficult to treat. Approximately 50% of patients diagnosed with sarcoma develop metastatic disease with so far very limited treatment options. The transmembrane protein B7-H3 reportedly is expressed in various malignancies, including different sarcoma subtypes. In several cancer entities B7-H3 expression is associated with poor prognosis. In turn, B7-H3 is considered a promising target for immunotherapeutic approaches. We here report on the preclinical characterization of a B7-H3xCD3 bispecific antibody in an IgG-based format, termed CC-3, for treatment of different sarcoma subtypes. We found B7-H3 to be expressed on all sarcoma cells tested and expression on sarcoma patients correlated with decreased progression-free and overall survival. CC-3 was found to elicit robust T cell responses against multiple sarcoma subtypes, resulting in significant activation, release of cytokines and effector molecules. In addition, CC-3 promoted T cell proliferation and differentiation, resulting in the generation of memory T cell subsets. Finally, CC-3 induced potent target cell lysis in a target cell restricted manner. Based on these results, a clinical trial evaluating CC-3 in soft tissue sarcoma is currently in preparation.

The role of programmed cell death in osteosarcoma: From pathogenesis to therapy

Osteosarcoma (OS) is a prevalent bone solid malignancy that primarily affects adolescents, particularly boys aged 14-19. This aggressive form of cancer often leads to deadly lung cancer due to its high migration ability. Experimental evidence suggests that programmed cell death (PCD) plays a crucial role in the development of osteosarcoma. Various forms of PCD, including apoptosis, ferroptosis, autophagy, necroptosis, and pyroptosis, contribute significantly to the progression of osteosarcoma. Additionally, different signaling pathways such as STAT3/c-Myc signal pathway, JNK signl pathway, PI3k/AKT/mTOR signal pathway, WNT/β-catenin signal pathway, and RhoA signal pathway can influence the development of osteosarcoma by regulating PCD in osteosarcoma cell. Therefore, targeting PCD and the associated signaling pathways could offer a promising therapeutic approach for treating osteosarcoma.

Peripheral Soluble Immune Checkpoint-Related Proteins Were Associated with Survival and Treatment Efficacy of Osteosarcoma Patients, a Cohort Study

BACKGROUND

The immune checkpoint blockade remains obscure in osteosarcoma (OS). We aim to explore the clinical significance of soluble immune checkpoint (ICK)-related proteins in OS.

METHODS

We profiled 14 soluble ICK-related proteins (BTLA, GITR, HVEM, IDO, LAG-3, PD-1, PD-L1, PD-L2, TIM-3, CD28, CD80, CD137, CD27, and CTLA-4) in the plasma of 76 OS patients and matched controls. We evaluated the associations between the biomarkers and the risk of OS using unconditional multivariate logistic regression. The multivariate Cox model was utilized to develop the prediction model of OS. Immune subtypes were established from the identified biomarkers. Transcriptional data from GEO were analyzed to elucidate potential mechanisms.

RESULTS

We found that sTIM3, sCD137, sIDO, and sCTLA4 were significantly correlated with OS risk (all p < 0.05). sBTLA, sPDL2, and sCD27 were significantly associated with the risk of lung metastasis, whereas sBTLA and sTIM3 were associated with the risk of disease progression. We also established an immune subtype based on sBTLA, sPD1, sTIM3, and sPDL2. Patients in the sICK-type2 subtype had significantly decreased progression-free survival (PFS) and lung metastasis-free survival (LMFS) than those in the sICK-type1 subtype (log-rank p = 2.8 × 10-2, 1.7 × 10-2, respectively). Interestingly, we found that the trend of LMFS and PFS in the subtypes of corresponding ICK genes' expression was opposite to the results in the blood (log-rank p = 2.6 × 10-4, 9.5 × 10-4, respectively).

CONCLUSION

Four soluble ICK-related proteins were associated with the survival of OS patients. Soluble ICK-related proteins could be promising biomarkers for the outcomes and immunotherapy of OS patients, though more research is warranted.

From standard therapies to monoclonal antibodies and immune checkpoint inhibitors - an update for reconstructive surgeons on common oncological cases

Malignancies represent a persisting worldwide health burden. Tumor treatment is commonly based on surgical and/or non-surgical therapies. In the recent decade, novel non-surgical treatment strategies involving monoclonal antibodies (mAB) and immune checkpoint inhibitors (ICI) have been successfully incorporated into standard treatment algorithms. Such emerging therapy concepts have demonstrated improved complete remission rates and prolonged progression-free survival compared to conventional chemotherapies. However, the in-toto surgical tumor resection followed by reconstructive surgery oftentimes remains the only curative therapy. Breast cancer (BC), skin cancer (SC), head and neck cancer (HNC), and sarcoma amongst other cancer entities commonly require reconstructive surgery to restore form, aesthetics, and functionality. Understanding the basic principles, strengths, and limitations of mAB and ICI as (neo-) adjuvant therapies and treatment alternatives for resectable or unresectable tumors is paramount for optimized surgical therapy planning. Yet, there is a scarcity of studies that condense the current body of literature on mAB and ICI for BC, SC, HNC, and sarcoma. This knowledge gap may result in suboptimal treatment planning, ultimately impairing patient outcomes. Herein, we aim to summarize the current translational endeavors focusing on mAB and ICI. This line of research may serve as an evidence-based fundament to guide targeted therapy and optimize interdisciplinary anti-cancer strategies.

3D Models of Sarcomas: The Next-generation Tool for Personalized Medicine

Sarcoma is a complex and heterogeneous cancer that has been difficult to study in vitro. While two-dimensional (2D) cell cultures and mouse models have been the dominant research tools, three-dimensional (3D) culture systems such as organoids have emerged as promising alternatives. In this review, we discuss recent developments in sarcoma organoid culture, with a focus on their potential as tools for drug screening and biobanking. We also highlight the ways in which sarcoma organoids have been used to investigate the mechanisms of gene regulation, drug resistance, metastasis, and immune interactions. Sarcoma organoids have shown to retain characteristics of in vivo biology within an in vitro system, making them a more representative model for sarcoma research. Our review suggests that sarcoma organoids offer a potential path forward for translational research in this field and may provide a platform for developing personalized therapies for sarcoma patients.

Oncolytic Virotherapy: A New Paradigm in Cancer Immunotherapy

Oncolytic viruses (OVs) are emerging as potential treatment options for cancer. Natural and genetically engineered viruses exhibit various antitumor mechanisms. OVs act by direct cytolysis, the potentiation of the immune system through antigen release, and the activation of inflammatory responses or indirectly by interference with different types of elements in the tumor microenvironment, modification of energy metabolism in tumor cells, and antiangiogenic action. The action of OVs is pleiotropic, and they show varied interactions with the host and tumor cells. An important impediment in oncolytic virotherapy is the journey of the virus into the tumor cells and the possibility of its binding to different biological and nonbiological vectors. OVs have been demonstrated to eliminate cancer cells that are resistant to standard treatments in many clinical trials for various cancers (melanoma, lung, and hepatic); however, there are several elements of resistance to the action of viruses per se. Therefore, it is necessary to evaluate the combination of OVs with other standard treatment modalities, such as chemotherapy, immunotherapy, targeted therapies, and cellular therapies, to increase the response rate. This review provides a comprehensive update on OVs, their use in oncolytic virotherapy, and the future prospects of this therapy alongside the standard therapies currently used in cancer treatment.

Identification of an ADME-related gene for forecasting the prognosis and responding to immunotherapy in sarcomas

There are more than 170 subtypes of sarcomas (SARC), which pose a challenge for diagnosis and patient management. Relatively simple or complex karyotypes play an indispensable role in the early diagnosis and effective treatment of SARC. The genes related to absorption, distribution, metabolism, and excretion (ADME) of a drug can serve as prognostic biomarkers of cancer and potential drug targets. In this study, a risk score signature was created. The SARC cohort was downloaded from The Cancer Genome Atlas (TCGA) database, and divided into high-risk group and low-risk group according to the median value of risk score. Compared with high-risk group, low-risk group has a longer survival time, which is also verified in osteosarcoma cohort from Therapeutically Applicable Research to Generate Effective Treatments (TARGET) database. In addition, the relationship between the signature and immunophenotypes, including status of immune cell infiltration and immune checkpoint expression, was explored. Then, we found that high-risk group is in immunosuppressive status. Finally, we verified that PPARD played a role as a carcinogen in osteosarcoma, which provided a direction for targeted treatment of osteosarcoma in the future. Generally speaking, the signature can not only help clinicians predict the prognosis of patients with SARC, but also provide a theoretical basis for developing more effective targeted drugs in the future.

LTX-315 and adoptive cell therapy using tumor-infiltrating lymphocytes generate tumor specific T cells in patients with metastatic soft tissue sarcoma

LTX-315 is an oncolytic peptide that elicits both local and systemic immune responses upon intratumoral injection. In the present pilot trial, we treated patients with metastatic soft tissue sarcoma with the combination of LTX-315 and adoptive T-cell therapy using in vitro expanded tumor-infiltrating lymphocytes. Six heavily pretreated patients were included in the trial and treated with LTX-315 of which four patients proceeded to adoptive T-cell therapy. Overall, the treatment was considered safe with only expected and manageable toxicity. The best overall clinical response was stable disease for 208 days, and in this patient, we detected tumor-reactive T cells in the blood that lasted until disease progression. In three patients T-cell reactivity against in silico predicted neoantigens was demonstrated. Additionally, de novo T-cell clones were generated and expanded in the blood following LTX-315 injections. In conclusion, this pilot study provides proof that it is feasible to combine LTX-315 and adoptive T-cell therapy, and that this treatment can induce systemic immune responses that resulted in stabilization of the disease in sarcoma patients with otherwise progressive disease. Further optimization of the treatment protocol is warranted to increase clinical activity. ClinicalTrials.gov Identifier: NCT03725605.

Outsmarting trogocytosis to boost CAR NK/T cell therapy

Chimeric antigen receptor (CAR) NK and T cell therapy are promising immunotherapeutic approaches for the treatment of cancer. However, the efficacy of CAR NK/T cell therapy is often hindered by various factors, including the phenomenon of trogocytosis, which involves the bidirectional exchange of membrane fragments between cells. In this review, we explore the role of trogocytosis in CAR NK/T cell therapy and highlight potential strategies for its modulation to improve therapeutic efficacy. We provide an in-depth analysis of trogocytosis as it relates to the fate and function of NK and T cells, focusing on its effects on cell activation, cytotoxicity, and antigen presentation. We discuss how trogocytosis can mediate transient antigen loss on cancer cells, thereby negatively affecting the effector function of CAR NK/T cells. Additionally, we address the phenomenon of fratricide and trogocytosis-associated exhaustion, which can limit the persistence and effectiveness of CAR-expressing cells. Furthermore, we explore how trogocytosis can impact CAR NK/T cell functionality, including the acquisition of target molecules and the modulation of signaling pathways. To overcome the negative effects of trogocytosis on cellular immunotherapy, we propose innovative approaches to modulate trogocytosis and augment CAR NK/T cell therapy. These strategies encompass targeting trogocytosis-related molecules, engineering CAR NK/T cells to resist trogocytosis-induced exhaustion and leveraging trogocytosis to enhance the function of CAR-expressing cells. By overcoming the limitations imposed by trogocytosis, it may be possible to unleash the full potential of CAR NK/T therapy against cancer. The knowledge and strategies presented in this review will guide future research and development, leading to improved therapeutic outcomes in the field of immunotherapy.

Integrative analysis of TROAP with molecular features, carcinogenesis, and related immune and pharmacogenomic characteristics in soft tissue sarcoma

Soft tissue sarcoma (STS) is an uncommon malignancy that often carries a grim prognosis. Trophinin-associated protein (TROAP) is augmented in a variety of tumors and can affect tumor proliferation. Nevertheless, the prognostic value and specific functions of TROAP in STS are still vague. Herein, we display that TROAP exhibits an augmented trend in STS, and its elevation correlates with a poor prognosis of STS. Furthermore, its reduction is related to increased immune cell infiltration, enhanced stroma, and elevation of immune activation. Meanwhile, the TROAP-derived genomic signature is validated to predict patient prognosis, immunotherapy, and drug response reliably. A nomogram constructed based on age, metastatic status, and a TROAP-derived risk score of an STS individual could be used to quantify the survival probability of STS. In addition, in vitro experiments have demonstrated that TROAP is overexpressed in STS, and the downregulation of TROAP could affect the proliferation, migration, metastasis, and cell cycle of STS cells. In summary, the TROAP expression is elevated in STS tissues and cells, which is related to the poor prognosis and malignant biological behaviors of STS. It could act as a potential prognostic biomarker for diagnosis and treatment of STS.

Functional Profiling of Soft Tissue Sarcoma Using Mechanistic Models

Soft tissue sarcoma is an umbrella term for a group of rare cancers that are difficult to treat. In addition to surgery, neoadjuvant chemotherapy has shown the potential to downstage tumors and prevent micrometastases. However, finding effective therapeutic targets remains a research challenge. Here, a previously developed computational approach called mechanistic models of signaling pathways has been employed to unravel the impact of observed changes at the gene expression level on the ultimate functional behavior of cells. In the context of such a mechanistic model, RNA-Seq counts sourced from the Recount3 resource, from The Cancer Genome Atlas (TCGA) Sarcoma project, and non-diseased sarcomagenic tissues from the Genotype-Tissue Expression (GTEx) project were utilized to investigate signal transduction activity through signaling pathways. This approach provides a precise view of the relationship between sarcoma patient survival and the signaling landscape in tumors and their environment. Despite the distinct regulatory alterations observed in each sarcoma subtype, this study identified 13 signaling circuits, or elementary sub-pathways triggering specific cell functions, present across all subtypes, belonging to eight signaling pathways, which served as predictors for patient survival. Additionally, nine signaling circuits from five signaling pathways that highlighted the modifications tumor samples underwent in comparison to normal tissues were found. These results describe the protective role of the immune system, suggesting an anti-tumorigenic effect in the tumor microenvironment, in the process of tumor cell detachment and migration, or the dysregulation of ion homeostasis. Also, the analysis of signaling circuit intermediary proteins suggests multiple strategies for therapy.

Clinico-demographic characteristics and outcomes of radiation-induced sarcomas (RIS): a CanSaRCC study

Background

Radiation-induced sarcomas (RIS) tend to have aggressive behaviour and because of their rarity, the most appropriate management for these malignancies is uncertain.

Objectives

Using the Canadian Sarcoma Research and Clinical Collaboration (CanSaRCC) database, a national sarcoma registry, we aimed to investigate prognostic factors and outcomes for RIS.

Design

Retrospective study of RIS patients treated from 1996 to 2021 at three Canadian centres.

Methods

RIS was defined as a sarcoma arising in a previously irradiated field following a 3+ year latency period, whose histology was distinct from the initially irradiated tumour. Clinicopathologic and treatment-related information was extracted from the CanSaRCC database. Overall survival (OS) was defined as the time from RIS diagnosis to death from any cause. Response rate (RR) to neoadjuvant chemotherapy (NACT) was based on physician assessment. Time-to-event analyses were estimated using the Kaplan-Meier method, with Cox regression for multivariate analysis. We considered a two-tailed p-value of <0.05 as statistically significant.

Results

One hundred seven tumours met the criteria for RIS and were divided into three subgroups: breast angiosarcoma (BAS, n = 54), osteosarcoma (OST, n = 16), and other soft-tissue sarcomas (STS, n = 37). Patients were mostly female (n = 85, 79%), treated initially for breast carcinomas (n = 54, 50.5%), and diagnosed with high-grade tumours (n = 61/71, 86%). None had evidence of synchronous metastasis. Patients with OST were younger (median age: 48 years, p < 0.001), and BAS had the shortest latency interval (8 versus 18 years for OST/STS, p < 0.001). Most patients underwent surgery, 76% (n = 76/100) R0; 24% (n = 26) received radiation therapy, mostly (n = 15, 57.7%) neoadjuvant. Among those receiving chemotherapy, 30 (75%) underwent NACT; among patients with documented response assessment, the RR was 68% (n = 17/25), being even higher in the BAS population (89.5%, n = 13/17). Median OS was 53 months (95% CI 34-101), with a 5-year OS of 47.6%; larger tumour size, high histologic grade and older age were independent prognostic factors for worse OS.

Conclusion

Surgery is standard, and NACT might be useful to downsize large lesions, especially in BAS patients. Raising RIS awareness is fundamental to promoting appropriate management and fostering research through multi-institutional collaborations.

CDK4/6-MEK Inhibition in MPNSTs Causes Plasma Cell Infiltration, Sensitization to PD-L1 Blockade, and Tumor Regression

PURPOSE

Malignant peripheral nerve sheath tumors (MPNST) are lethal, Ras-driven sarcomas that lack effective therapies. We investigated effects of targeting cyclin-dependent kinases 4 and 6 (CDK4/6), MEK, and/or programmed death-ligand 1 (PD-L1) in preclinical MPNST models.

EXPERIMENTAL DESIGN

Patient-matched MPNSTs and precursor lesions were examined by FISH, RNA sequencing, IHC, and Connectivity-Map analyses. Antitumor activity of CDK4/6 and MEK inhibitors was measured in MPNST cell lines, patient-derived xenografts (PDX), and de novo mouse MPNSTs, with the latter used to determine anti-PD-L1 response.

RESULTS

Patient tumor analyses identified CDK4/6 and MEK as actionable targets for MPNST therapy. Low-dose combinations of CDK4/6 and MEK inhibitors synergistically reactivated the retinoblastoma (RB1) tumor suppressor, induced cell death, and decreased clonogenic survival of MPNST cells. In immune-deficient mice, dual CDK4/6-MEK inhibition slowed tumor growth in 4 of 5 MPNST PDXs. In immunocompetent mice, combination therapy of de novo MPNSTs caused tumor regression, delayed resistant tumor outgrowth, and improved survival relative to monotherapies. Drug-sensitive tumors that regressed contained plasma cells and increased cytotoxic T cells, whereas drug-resistant tumors adopted an immunosuppressive microenvironment with elevated MHC II-low macrophages and increased tumor cell PD-L1 expression. Excitingly, CDK4/6-MEK inhibition sensitized MPNSTs to anti-PD-L1 immune checkpoint blockade (ICB) with some mice showing complete tumor regression.

CONCLUSIONS

CDK4/6-MEK inhibition induces a novel plasma cell-associated immune response and extended antitumor activity in MPNSTs, which dramatically enhances anti-PD-L1 therapy. These preclinical findings provide strong rationale for clinical translation of CDK4/6-MEK-ICB targeted therapies in MPNST as they may yield sustained antitumor responses and improved patient outcomes.

Patient-Derived Organoids as a Promising Tool for Multimodal Management of Sarcomas

The management of sarcomas, a diverse group of cancers arising from connective tissues, presents significant challenges due to their heterogeneity and limited treatment options. Patient-derived sarcoma organoids (PDSOs) have emerged as a promising tool in the multimodal management of sarcomas, offering unprecedented opportunities for personalized medicine and improved treatment strategies. This review aims to explore the potential of PDSOs as a promising tool for multimodal management of sarcomas. We discuss the establishment and characterization of PDSOs, which realistically recapitulate the complexity and heterogeneity of the original tumor, providing a platform for genetic and molecular fidelity, histological resemblance, and functional characterization. Additionally, we discuss the applications of PDSOs in pathological and genetic evaluation, treatment screening and development, and personalized multimodal management. One significant advancement of PDSOs lies in their ability to guide personalized treatment decisions, enabling clinicians to assess the response and efficacy of different therapies in a patient-specific manner. Through continued research and development, PDSOs hold the potential to revolutionize sarcoma management and drive advancements in personalized medicine, biomarker discovery, preclinical modeling, and therapy optimization. The integration of PDSOs into clinical practice can ultimately improve patient outcomes and significantly impact the field of sarcoma treatment.

Novel-fosfamide monotherapy or in combination with doxorubicin versus doxorubicin alone in patients with advanced soft tissue sarcoma: A pooled analysis of randomized clinical trials

BACKGROUND

Novel-fosfamides (NFOs) belong to active metabolites of ifosfamide that bypass the generation of toxic byproducts. In this analysis, we aimed to comprehensively assess the benefits and risks of NFO monotherapy or in combination with doxorubicin (DOX) versus single-drug DOX in previously untreated patients with advanced soft-tissue sarcoma (ASTS).

METHODS

Online PubMed, Web of Science, Embase, and Cochrane CENTRAL databases were systematically searched on April 26, 2022. Objective response rate and disease control rate were primary outcomes. Overall survival (OS), progression-free survival (PFS), and grade ≥ 3 treatment-related adverse events were secondary outcomes.

RESULTS

In all, 3 randomized clinical trials with a total of 1207 ASTS patients were eligible. DOX plus NFO combination therapy showed higher risk ratios of objective response rate (1.50, 95% CI 1.20-1.68, P = .0003) and disease control rate (1.15, 95% CI 1.05-1.27, P = .0030) compared with DOX monotherapy. Nevertheless, NFO-based monotherapy and combination therapy were found no improvements on OS (hazard ratio 0.93, 95% CI 0.52-1.65, P = .8050) and PFS (hazard ratio 0.88, 95% CI 0.54-1.43, P = .6088) against DOX. More incidences of grade 3 or worse anemia, thrombocytopenia, stomatitis, diarrhea, constipation, and febrile neutropenia were observed in NFO-based treatments.

CONCLUSION

Adding NFO to DOX as first-line therapy improved the responses in ASTS patients but did not prolong OS and PFS. Grade 3 or worse treatment-related adverse events should be treated with caution during the NFO-based therapies.

Surgical Site Infection Is Not Associated with 1-Year Progression-Free Survival After Endoprosthetic Reconstruction for Lower-Extremity Osteosarcoma: A Secondary Analysis of PARITY Study Data

BACKGROUND

Although there is evidence suggesting that postoperative infection confers a survival benefit in osteosarcoma treated with resection and endoprosthetic reconstruction, there have been no prospective studies to date to support these findings. This secondary analysis of Prophylactic Antibiotic Regimens in Tumor Surgery (PARITY) study data examines the relationship between surgical site infection (SSI) and disease progression within 12 months after limb salvage surgery.

METHODS

The PARITY trial was an international, multicenter, prospective randomized controlled trial of 604 patients who underwent resection of a lower-extremity bone tumor and endoprosthetic reconstruction. Our primary outcome was progression-free survival (PFS) at 1 year following surgery among the patients with osteosarcoma. Subgroup analyses by disease stage at presentation and infection severity were also performed. Cox proportional hazard models were employed to examine the association between clinical and tumor characteristics, SSI, and PFS. Kaplan-Meier analysis was used to determine the effect of SSI on PFS.

RESULTS

The 274 PARITY patients with osteosarcoma were included in this secondary analysis. Thirty-two (11.7%) of the patients presented with metastasis at baseline; 53 (19.3%) of the patients developed an SSI. There was no difference in 1-year PFS between patients with and without SSI. There was no decreased risk of disease progression at 1 year in patients with localized disease at baseline who developed an SSI (hazard ratio [HR] = 1.21; 95% confidence interval [CI] = 0.64 to 2.28). Infection was associated with increased disease progression at 1 year in patients with baseline metastases (HR = 4.26; 95% CI = 1.11 to 16.3).

CONCLUSIONS

No positive association was detected between postoperative infection and PFS at 1 year following surgery in this secondary analysis of prospective data. However, this analysis suggests infection could be a risk factor for early disease progression in patients with baseline metastases, and future investigations may better elucidate the association between disease burden and the host immune response to advance immunotherapeutic strategies for osteosarcoma.

LEVEL OF EVIDENCE

Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.

Deciphering the role of NETosis-related signatures in the prognosis and immunotherapy of soft-tissue sarcoma using machine learning

Background: Soft-tissue sarcomas (STSs) are a rare type of cancer, accounting for about 1% of all adult cancers. Treatments for STSs can be difficult to implement because of their diverse histological and molecular features, which lead to variations in tumor behavior and response to therapy. Despite the growing importance of NETosis in cancer diagnosis and treatment, researches on its role in STSs remain limited compared to other cancer types. Methods: The study thoroughly investigated NETosis-related genes (NRGs) in STSs using large cohorts from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. The Least Absolute Shrinkage and Selection Operator (LASSO) regression analysis and Support Vector Machine Recursive Feature Elimination (SVM-RFE) were employed for screening NRGs. Utilizing single-cell RNA-seq (scRNA-seq) dataset, we elucidated the expression profiles of NRGs within distinct cellular subpopulations. Several NRGs were validated by quantitative PCR (qPCR) and our proprietary sequencing data. To ascertain the impact of NRGs on the sarcoma phenotype, we conducted a series of in vitro experimental investigations. Employing unsupervised consensus clustering analysis, we established the NETosis clusters and respective NETosis subtypes. By analyzing DEGs between NETosis clusters, an NETosis scoring system was developed. Results: By comparing the outcomes obtained from LASSO regression analysis and SVM-RFE, 17 common NRGs were identified. The expression levels of the majority of NRGs exhibited notable dissimilarities between STS and normal tissues. The correlation with immune cell infiltration were demonstrated by the network comprising 17 NRGs. Patients within various NETosis clusters and subtypes exhibited different clinical and biological features. The prognostic and immune cell infiltration predictive capabilities of the scoring system were deemed efficient. Furthermore, the scoring system demonstrated potential for predicting immunotherapy response. Conclusion: The current study presents a systematic analysis of NETosis-related gene patterns in STS. The results of our study highlight the critical role NRGs play in tumor biology and the potential for personalized therapeutic approaches through the application of the NETosis score model in STS patients.

Multi-modal efficacy of a chimeric vesiculovirus expressing the Morreton glycoprotein in sarcoma

Vesiculoviruses are attractive oncolytic virus platforms due to their rapid replication, appreciable transgene capacity, broad tropism, limited preexisting immunity, and tumor selectivity through type I interferon response defects in malignant cells. We developed a synthetic chimeric virus (VMG) expressing the glycoprotein (G) from Morreton virus (MorV) and utilizing the remaining structural genes from vesicular stomatitis virus (VSV). VMG exhibited in vitro efficacy by inducing oncolysis in a broad range of sarcoma subtypes across multiple species. Notably, all cell lines tested showed the ability of VMG to yield productive infection with rapid replication kinetics and induction of apoptosis. Furthermore, pilot safety evaluations of VMG in immunocompetent, non-tumor-bearing mice showed an absence of toxicity with intranasal doses as high as 1e10 50% tissue culture infectious dose (TCID50)/kg. Locoregional administration of VMG in vivo resulted in tumor reduction in an immunodeficient Ewing sarcoma xenograft at doses as low as 2e5 TCID50. In a murine syngeneic fibrosarcoma model, while no tumor inhibition was achieved with VMG, there was a robust induction of CD8+ T cells within the tumor. The studies described herein establish the promising potential for VMG to be used as a novel oncolytic virotherapy platform with anticancer effects in sarcoma.

Immunotherapy Plus Radiotherapy for the Treatment of Sarcomas: Is There a Potential for Synergism?

Soft tissue sarcoma (STS) is a highly heterogeneous malignant tumor derived from mesenchymal tissue. Advanced STS has a poor response to the current anti-cancer therapeutic options, with a median overall survival of less than two years. Thus, new and more effective treatment methods for STS are needed. Increasing evidence has shown that immunotherapy and radiotherapy have synergistic therapeutic effects against malignant tumors. In addition, immunoradiotherapy has yielded positive results in clinical trials for various cancers. In this review, we discuss the synergistic mechanism of immunoradiotherapy in cancer treatment and the application of this combined regimen for the treatment of several cancers. In addition, we summarize the existing evidence on the use of immunoradiotherapy for the treatment of STS and the relevant clinical trials that are currently ongoing. Furthermore, we identify challenges in the use of immunoradiotherapy for the treatment of sarcomas and propose methods and precautions for overcoming these challenges. Lastly, we propose clinical research strategies and future research directions to help in the research and treatment of STS.

Treatment of De-Differentiated Liposarcoma in the Era of Immunotherapy

Well-differentiated/de-differentiated liposarcoma (WDLPS/DDLPS) is one of the most common histologic subtypes of soft tissue sarcoma (STS); however, treatment options remain limited. WDLPS and DDLPS both exhibit the characteristic amplification of chromosome region 12q13-15, which contains the genes CDK4 and MDM2. DDLPS exhibits higher amplification ratios of these two and carries additional genomic lesions, including the amplification of chromosome region 1p32 and chromosome region 6q23, which may explain the more aggressive biology of DDLPS. WDLPS does not respond to systemic chemotherapy and is primarily managed with local therapy, including multiple resections and debulking procedures whenever clinically feasible. In contrast, DDLPS can respond to chemotherapy drugs and drug combinations, including doxorubicin (or doxorubicin in combination with ifosfamide), gemcitabine (or gemcitabine in combination with docetaxel), trabectedin, eribulin, and pazopanib. However, the response rate is generally low, and the response duration is usually short. This review highlights the clinical trials with developmental therapeutics that have been completed or are ongoing, including CDK4/6 inhibitors, MDM2 inhibitors, and immune checkpoint inhibitors. This review will also discuss the current landscape in assessing biomarkers for identifying tumors sensitive to immune checkpoint inhibitors.

Activity of TNT: a phase 2 study using talimogene laherparepvec, nivolumab and trabectedin for previously treated patients with advanced sarcomas (NCT# 03886311)

Background

Intratumoral injection of talimogene laherparepvec evokes a cytotoxic immune response. Therefore, the combination of talimogene laherparepvec with trabectedin and nivolumab may have synergistic effects in advanced sarcomas.

Patients and methods

This phase 2 trial was conducted from May 30, 2019 to January 31, 2022. Endpoints: Primary: Progression free survival rate at month 12. Secondary: Best overall response, progression free survival rate at 6 and 9 months, overall survival rate at 6, 9, and 12 months, incidence of conversion of an unresectable tumor to a resectable tumor, and incidence of adverse events. Eligible patients had to be ≥ 18 years of age, have advanced histologically proven sarcoma, at least 1 previous chemotherapy regimen, and at least one accessible tumor for intratumoral injection. Treatment: Trabectedin intravenously (1.2 mg/m² q3 weeks), nivolumab intravenously (3 mg/kg q2 weeks), and intratumoral talimogene laherparepvec (1x10⁸ plaque forming units/ml q2 weeks).

Results

Median time of follow-up: 15.2 months. Efficacy analysis: Thirty-nine patients who had completed at least one treatment cycle and had a follow-up computerized tomography were evaluable for efficacy analysis. Median number of prior therapies: 4 (range 1-11). Progression free survival rate at month 12, 36.7%. Confirmed Best Overall Response by Response Evaluation Criteria in Solid Tumors v1.1 = 3 partial responses, 30 stable disease, 6 progressive disease. Best Overall Response Rate, 7.7%, Disease Control Rate, 84.6%; median progression free survival, 7.8 (95% Confidence Intervals: 4.1-13.1) months; 6-, 9-, 12-month progression free survival rates, 54.5%/45.9%/36.7%; median overall survival 19.3 (95% Confidence Intervals: 12.8 -.) months; 6-, 9- and 12-month overall survival rate, 86.9%/73.3%/73.3%. One patient had a complete surgical resection. Fifty percent of patients had a ≥ grade 3 treatment related adverse events which included anemia (6%), thrombocytopenia (6%), neutropenia (4%), increased alanine transaminase (4%), decreased left ventricular ejection fraction (4%), dehydration (4%), hyponatremia (4%).

Conclusions

Taken together these data suggest that the TNT regimen is effective and safe for advanced previously treated sarcomas, and is worth being further studied in a randomized phase 3 trial as first- or second- line treatment for patients with advanced sarcomas.

Tantalum-Zirconium Co-Doped Metal-Organic Frameworks Sequentially Sensitize Radio-Radiodynamic-Immunotherapy for Metastatic Osteosarcoma

Due to radiation resistance and the immunosuppressive microenvironment of metastatic osteosarcoma, novel radiosensitizers that can sensitize radiotherapy (RT) and antitumor immunity synchronously urgently needed. Here, the authors developed a nanoscale metal-organic framework (MOF, named TZM) by co-doping high-atomic elements Ta and Zr as metal nodes and porphyrinic molecules (tetrakis(4-carboxyphenyl)porphyrin (TCPP)) as a photosensitizing ligand. Given the 3D arrays of ultra-small heavy metals, porous TZM serves as an efficient attenuator absorbing X-ray energy and sensitizing hydroxyl radical generation for RT. Ta-Zr co-doping narrowed the highest occupied molecular orbital-lowest unoccupied molecular orbital (HOMO-LUMO) energy gap and exhibited close energy levels between the singlet and triplet photoexcited states, facilitating TZM transfer energy to the photosensitizer TCPP to sensitize singlet oxygen (1 O2 ) generation for radiodynamic therapy (RDT). The sensitized RT-RDT effects of TZM elicit a robust antitumor immune response by inducing immunogenic cell death, promoting dendritic cell maturation, and upregulating programmed cell death protein 1 (PD-L1) expression via the cGAS-STING pathway. Furthermore, a combination of TZM, X-ray, and anti-PD-L1 treatments amplify antitumor immunotherapy and efficiently arrest osteosarcoma growth and metastasis. These results indicate that TZM is a promising radiosensitizer for the synergistic RT and immunotherapy of metastatic osteosarcoma.

SAINT: A Phase I/Expanded Phase II Study Using Safe Amounts of Ipilimumab, Nivolumab and Trabectedin as First-Line Treatment of Advanced Soft Tissue Sarcoma

BACKGROUND

This Phase 1/2 study is based on the hypothesis that immune checkpoint inhibitors are more effective when given earlier in the course of the disease for advanced soft tissue sarcoma.

METHODS

Phase I endpoints-maximum tolerated dose in previously treated patients; Phase II endpoints-best response, progression free survival and overall survival and incidence of adverse events in previously untreated patients; Phase I treatments-escalating doses of trabectedin (1.0, 1.2, 1.5 mg/m²) as continuous intravenous infusion over 24 h every 3 weeks, 1 mg/kg of ipilimumab given intravenously every 12 weeks, and 3 mg/kg of nivolumab given intravenously every 2 weeks; Phase II treatments-maximum tolerated dose of trabectedin and defined doses of ipilimumab and nivolumab.

RESULTS

Phase I (n = 9)-the maximum tolerated dose of trabectedin was 1.2 mg/m²; Phase II (n = 79)-6 complete responses, 14 partial responses, 49 stable disease, 25.3% best response rate, 87.3% disease control rate; median progression-free survival, 6.7 months (CI 95%: 4.4-7.9), median overall survival, 24.6 months (CI 95%: 17.0-.); Grade 3/4 therapy-related adverse events (n = 92)-increased ALT (25%), fatigue (8.7%), increased AST (8.7%), decreased neutrophil count (5.4%) and anemia (4.6%).

CONCLUSION

SAINT is a safe and effective first-line treatment for advanced soft tissue sarcoma.

Nanomedicine embraces cancer radio-immunotherapy: mechanism, design, recent advances, and clinical translation

Cancer radio-immunotherapy, integrating external/internal radiation therapy with immuno-oncology treatments, emerges in the current management of cancer. A growing number of pre-clinical studies and clinical trials have recently validated the synergistic antitumor effect of radio-immunotherapy, far beyond the "abscopal effect", but it suffers from a low response rate and toxicity issues. To this end, nanomedicines with an optimized design have been introduced to improve cancer radio-immunotherapy. Specifically, these nanomedicines are elegantly prepared by incorporating tumor antigens, immuno- or radio-regulators, or biomarker-specific imaging agents into the corresponding optimized nanoformulations. Moreover, they contribute to inducing various biological effects, such as generating in situ vaccination, promoting immunogenic cell death, overcoming radiation resistance, reversing immunosuppression, as well as pre-stratifying patients and assessing therapeutic response or therapy-induced toxicity. Overall, this review aims to provide a comprehensive landscape of nanomedicine-assisted radio-immunotherapy. The underlying working principles and the corresponding design strategies for these nanomedicines are elaborated by following the concept of "from bench to clinic". Their state-of-the-art applications, concerns over their clinical translation, along with perspectives are covered.

Novel pyroptosis-associated genes signature for predicting the prognosis of sarcoma and validation

BACKGROUND

Sarcoma is a rare mesenchymal malignant tumor. Recently, pyroptosis has been reported to be a mode of programmed cell death. Nonetheless, levels of pyroptosis-associated genes in sarcoma and its relevance to prognostic outcomes are yet to be elucidated.

RESULTS

Sarcoma cases were classified into two subtypes with regards to differentially expressed genes. We established a profile composed of seven genes and classified the sarcoma patients into low- and high-risk groups through least absolute shrinkage and selection operator Cox regression. Survival rate of low-risk sarcoma patients was markedly higher, relative to high-risk group (P<0.001). In combination with clinical features, the risk score was established to be an independent predictive factor for OS of sarcoma patients. Chemotherapeutic drug sensitivity response analysis found 65 drugs with higher drug sensitivity in low-risk, than in high-risk group and 14 drugs with higher drug sensitivity in the high-risk patient group, compared with low-risk patient group. In addition, functional enrichment, pathway and gene mutation of the two modules were analyzed. Finally, we used qRT-PCR to detect the expression of seven pyroptosis-related genes in tumor cells, and human skeletal muscle cells, compared with human skeletal muscle cells, PODXL2, LRRC17, GABRA3, SCUBE3 and RFLNB genes show high expression levels in tumor cells, while IGHG2 and hepatic leukemia factor show low expression levels in tumor cells.

CONCLUSIONS

Our research suggest that pyroptosis is closely associated with sarcoma, and these findings confirm that pyroptosis-associated seven genes have a critical role in sarcoma and are potential prognostic factors for sarcoma.

3D tumor explant as a novel platform to investigate therapeutic pathways and predictive biomarkers in cancer patients

Immunotherapy with immune checkpoint inhibitors can induce durable clinical responses in different human malignancies but the number of responding patients remains globally modest. The limited therapeutic efficacy of ICI depends on multiple factors, among which the immune suppressive features of the tumor microenvironment play a key role. For this reason, experimental models that enable dissection of the immune-hostile tumor milieu components are required to unravel how to overcome resistance and obtain full-fledged anti-tumor immunity. Recent evidence supports the usefulness of 3D ex vivo systems in retaining features of tumor microenvironment to elucidate molecular and immunologic mechanisms of response and resistance to immune checkpoint blockade. In this perspective article we discuss the recent advances in patient-derived 3D tumor models and their potential in support of treatment decision making in clinical setting. We will also share our experience with dynamic bioreactor tumor explant culture of samples from melanoma and sarcoma patients as a reliable and promising platform to unravel immune responses to immune checkpoint inhibitors.

Single-Cell Transcriptome Analysis Reveals Paraspeckles Expression in Osteosarcoma Tissues

Nuclear paraspeckles are subnuclear bodies contracted by nuclear-enriched abundant transcript 1 (NEAT1) long non-coding RNA, localised in the interchromatin space of mammalian cell nuclei. Paraspeckles have been critically involved in tumour progression, metastasis and chemoresistance. To this date, there are limited findings to suggest that paraspeckles, NEAT1 and heterogeneous nuclear ribonucleoproteins (hnRNPs) directly or indirectly play roles in osteosarcoma progression. Herein, we analysed NEAT1, paraspeckle proteins (SFPQ, PSPC1 and NONO) and hnRNP members (HNRNPK, HNRNPM, HNRNPR and HNRNPD) gene expression in 6 osteosarcoma tumour tissues using the single-cell RNA-sequencing method. The normalised data highlighted that the paraspeckles transcripts were highly abundant in osteoblastic OS cells, except NEAT1, which was highly expressed in myeloid cell 1 and 2 subpopulations.

Combinations of Chemotherapy and PD-1/PD-L1 Inhibitors in Sarcoma

OPINION STATEMENT

While no PD-1 inhibitor has been FDA approved for use in sarcoma or proven efficacious in a randomized trial, the use of single agent PD-1 inhibitors is standard-of-care and recommended by the NCCN guidelines in certain specific subtypes and situations. Even while the role of immunotherapy is still being defined in sarcoma, there is rising interest in combinations of PD-1 inhibitors with standard-of-care treatments, especially chemotherapy. Recently, several early phase trials have suggested potential benefits for chemotherapy in combination with PD-1 inhibitors. Although some physicians are already combining PD-1 inhibitors and chemotherapy for sarcoma off-label in the community, we believe more data is necessary. We support further evaluation of these combinations in well-designed clinical trials.

Harnessing immunomodulation during DNA damage in Ewing sarcoma

Ewing sarcoma is a fusion-oncoprotein-driven primary bone tumor most commonly diagnosed in adolescents. Given the continued poor outcomes for patients with metastatic and relapsed Ewing sarcoma, testing innovative therapeutic approaches is essential. Ewing sarcoma has been categorized as a 'BRCAness' tumor with emerging data characterizing a spectrum of DNA damage repair defects within individual Ewing tumors, including the presence of EWSR1::FLI1 itself, recurrent somatic mutations, and rare germline-based defects. It is critical to understand the cumulative impact of various DNA damage repair defects on an individual Ewing tumor's response to therapy. Further, in addition to DNA-damage-directed therapies, subsets of Ewing tumors may be more susceptible to DNA-damage/immunotherapy combinations given the significant cross-talk between DNA damage and inflammatory pathways in the tumor microenvironment. Here we review potential approaches utilizing DNA-damaging agents as modulators of the Ewing tumor immune microenvironment, with a focus on radiation and opportunities during disease metastasis and relapse.

B7-H3-targeting Fc-optimized antibody for induction of NK cell reactivity against sarcoma

Natural killer (NK) cells largely contribute to antibody-dependent cellular cytotoxicity (ADCC), a central factor for success of monoclonal antibodies (mAbs) treatment of cancer. The B7 family member B7-H3 (CD276) recently receives intense interest as a novel promising target antigen for immunotherapy. B7-H3 is highly expressed in many tumor entities, whereas expression on healthy tissues is rather limited. We here studied expression of B7-H3 in sarcoma, and found substantial levels to be expressed in various bone and soft-tissue sarcoma subtypes. To date, only few immunotherapeutic options for treatment of sarcomas that are limited to a minority of patients are available. We here used a B7-H3 mAb to generate chimeric mAbs containing either a wildtype Fc-part (8H8_WT) or a variant Fc part with amino-acid substitutions (S239D/I332E) to increase affinity for CD16 expressing NK cells (8H8_SDIE). In comparative studies we found that 8H8_SDIE triggers profound NK cell functions such as activation, degranulation, secretion of IFNγ and release of NK effector molecules, resulting in potent lysis of different sarcoma cells and primary sarcoma cells derived from patients. Our findings emphasize the potential of 8H8_SDIE as novel compound for treatment of sarcomas, particularly since B7-H3 is expressed in bone and soft-tissue sarcoma independent of their subtype.

Immune checkpoints in osteosarcoma: Recent advances and therapeutic potential

Osteosarcoma is the most common primary malignant bone tumor and is associated with a high risk of recurrence and distant metastasis. Effective treatment for osteosarcoma, especially advanced osteosarcoma, has stagnated over the past four decades. The advent of immune checkpoint inhibitor (ICI) has transformed the treatment paradigm for multiple malignant tumor types and indicated a potential therapeutic strategy for osteosarcoma. In this review, we discuss recent advances in immune checkpoints, including programmed cell death protein-1 (PD-1), programmed cell death protein ligand-1 (PD-L1), and cytotoxic T lymphocyte-associated antigen-4 (CTLA-4), and their related ICIs for osteosarcoma treatment. We present the main existing mechanisms of resistance to ICIs therapy in osteosarcoma. Moreover, we summarize the current strategies for improving the efficacy of ICIs in osteosarcoma and address the potential predictive biomarkers of ICIs treatment in osteosarcoma.

First-line Anti-GD2 Therapy Combined With Consolidation Chemotherapy in 3 Patients With Newly Diagnosed Metastatic Ewing Sarcoma or Ewing-like Sarcoma

Despite multimodal therapy, the prognosis of patients with metastatic Ewing sarcoma (ES) remains poor, with new treatments urgently needed. The disialoganglioside GD2, a well-established tumor-associated antigen, is expressed in 40% to 90% of ES cells, making it a suitable therapeutic target. Here we report 3 cases with newly diagnosed, metastatic, GD2-positive ES or Ewing-like sarcoma treated with the anti-GD2 antibody dinutuximab beta in addition to standard chemotherapeutic regimens. Treatment was well-tolerated, and all patients achieved complete remission, without evidence of relapse. First-line anti-GD2 immunotherapy in patients with metastatic, GD2-positive ES or Ewing-like sarcoma represents a promising therapeutic option that warrants further clinical evaluation.

PD-1, PD-L1, NY-ESO-1, and MAGE-A4 expression in cutaneous angiosarcoma: A case report

RATIONALE

The genomic alteration of cutaneous angiosarcoma (cAS) is complex. Treatment efficacy of immunotherapy for cAS remains controversial and prognosis remains poor. Herein, we report a case of cAS with programmed cell death 1, programmed cell death ligand-1, New York esophageal squamous cell carcinoma-1, and melanoma-associated antigen 4.

PATIENT CONCERNS

A 69-year-old man presented with a chief complaint of left thumb pain, with a soft tissue mass in the palmar side of the thumb. He had no past medical history. Three months prior, the man experienced the pain while scuba diving. He visited a nearby clinic, and magnetic resonance imaging revealed a soft tissue tumor on the palmar side of the thumb. He was referred to our hospital and a marginal excisional biopsy was performed.

DIAGNOSIS

Pathological findings revealed an angiosarcoma with high-flow serpentine vessels.

INTERVENTIONS

An excision was performed from the base of the thumb to achieve a wide margin.

OUTCOMES

One year after the treatment, the patient has not experienced recurrence, metastasis, or complications.

LESSONS

Histopathology of the excised specimen was positive for programmed cell death 1, programmed cell death ligand-1, New York esophageal squamous cell carcinoma-1, and melanoma-associated antigen 4; their expression may be a therapeutic target for cAS. Combining immunotherapy with surgical treatment may be effective for cAS.

Transcriptome Analysis of Tumor-Infiltrating Lymphocytes Identifies NK Cell Gene Signatures Associated With Lymphocyte Infiltration and Survival in Soft Tissue Sarcomas

Purpose

Clinical successes using current T-cell based immunotherapies have been limited in soft tissue sarcomas (STS), while pre-clinical studies have shown evidence of natural killer (NK) cell activity. Since tumor immune infiltration, especially tumor-infiltrating lymphocytes, is associated with improved survival in most solid tumors, we sought to evaluate the gene expression profile of tumor and blood NK and T cells, as well as tumor cells, with the goal of identifying potential novel immune targets in STS.

Experimental Design

Using fluorescence-activated cell sorting, we isolated blood and tumor-infiltrating CD3^-CD56⁺ NK and CD3⁺ T cells and CD45^- viable tumor cells from STS patients undergoing surgery. We then evaluated differential gene expression (DGE) of these purified populations with RNA sequencing analysis. To evaluate survival differences and validate primary DGE results, we also queried The Cancer Genome Atlas (TCGA) database to compare outcomes stratified by bulk gene expression.

Results

Sorted intra-tumoral CD3⁺ T cells showed significant upregulation of established activating (CD137) and inhibitory genes (TIM-3) compared to circulating T cells. In contrast, intra-tumoral NK cells did not exhibit upregulation of canonical cytotoxic genes (IFNG, GZMB), but rather significant DGE in mitogen signaling (DUSP4) and metabolic function (SMPD3, SLC7A5). Tumors with higher NK and T cell infiltration exhibited significantly increased expression of the pro-inflammatory receptor TLR4 in sorted CD45^- tumor cells. TCGA analysis revealed that tumors with high TLR4 expression (P = 0.03) and low expression of STMN1 involved in microtubule polymerization (P < 0.001) were associated with significantly improved survival.

Conclusions

Unlike T cells, which demonstrate significant DGE consistent with upregulation of both activating and inhibiting receptors in tumor-infiltrating subsets, NK cells appear to have more stable gene expression between blood and tumor subsets, with alterations restricted primarily to metabolic pathways. Increased immune cell infiltration and improved survival were positively correlated with TLR4 expression and inversely correlated with STMN1 expression within tumors, suggesting possible novel therapeutic targets for immunotherapy in STS.

Synergy of a STING agonist and an IL-2 superkine in cancer immunotherapy against MHC I-deficient and MHC I+ tumors

Cyclic dinucleotides (CDN) and Toll-like receptor (TLR) ligands mobilize antitumor responses by natural killer (NK) cells and T cells, potentially serving as complementary therapies to immune checkpoint therapy. In the clinic thus far, however, CDN therapy targeting stimulator of interferon genes (STING) protein has yielded mixed results, perhaps because it initiates responses potently but does not provide signals to sustain activation and proliferation of activated cytotoxic lymphocytes. To improve efficacy, we combined CDN with a half life-extended interleukin-2 (IL-2) superkine, H9-MSA (mouse serum albumin). CDN/H9-MSA therapy induced dramatic long-term remissions of the most difficult to treat major histocompatibility complex class I (MHC I)–deficient and MHC I+ tumor transplant models. H9-MSA combined with CpG oligonucleotide also induced potent responses. Mechanistically, tumor elimination required CD8 T cells and not NK cells in the case of MHC I+ tumors and NK cells but not CD8 T cells in the case of MHC-deficient tumors. Furthermore, combination therapy resulted in more prolonged and more intense NK cell activation, cytotoxicity, and expression of cytotoxic effector molecules in comparison with monotherapy. Remarkably, in a primary autochthonous sarcoma model that is refractory to PD-1 checkpoint therapy, the combination of CDN/H9-MSA with checkpoint therapy yielded long-term remissions in the majority of the animals, mediated by T cells and NK cells. This combination therapy has the potential to activate responses in tumors resistant to current therapies and prevent MHC I loss accompanying acquired resistance of tumors to checkpoint therapy.

Case Report: Retroperitoneal Sarcoma in Six Operations: Our Experience in Operative Management of Blood Vessels

Here we introduce a case of retroperitoneal liposarcoma, which is characterized by repeated recurrences after surgery, and has undergone a total of 6 operations. The diameter of the tumor was about 26 cm at the time of the patient's diagnosis. The imaging examination revealed that the surrounding organs and blood vessels were invaded, which brought great challenges to radical resection. The postoperative pathology of the patient’s first operation was dedifferentiated liposarcoma, and some areas showed myxofibrosarcoma differentiation. With the recurrence of sarcoma, myxofibrosarcoma dedifferentiated into rhabdomyosarcoma, and malignant fibrous histiocytoma appeared in some areas. How to treat this type of patient after recurrence? How to deal with blood vessels wrapped by sarcoma during surgery? The medical community has not yet reached the same conclusion. We describe the process of treating the patient and the experience of dealing with blood vessels during surgery.

A Multidisciplinary Approach to Complex Dermal Sarcomas Ensures an Optimal Clinical Outcome

Primary dermal sarcomas (PDS) belong to a highly clinically, genetically and pathologically heterogeneous group of rare malignant mesenchymal tumours primarily involving the dermis or the subcutaneous tissue. The tumours are classified according to the mesenchymal tissue from which they originate: dermal connective tissue, smooth muscle or vessels. Clinically, PDS may mimic benign soft tissue lesions such as dermatofibromas, hypertrophic scarring, etc. This may cause substantial diagnostic delay. As a group, PDS most commonly comprises the following clinicopathological forms of dermal sarcomas: dermatofibrosarcoma protuberans (DFSP), atypical fibroxanthoma (AFX), dermal undifferentiated pleomorphic sarcoma (DUPS), leiomyosarcoma (LMS), and vascular sarcomas (Kaposi’s sarcoma, primary angiosarcoma, and radiation-induced angiosarcoma). This clinical entity has a broad spectrum regarding malignant potential; however, local aggressive behaviour in some forms causes surgical challenges. Preoperative, individualised surgical planning with complete free margins is pivotal along with a multidisciplinary approach and collaboration across highly specialised surgical and medical specialties. The present review gives a structured overview of the most common forms of dermal sarcomas including surgical recommendations and examples for advanced reconstructions as well as the current adjunctive medical treatment strategies. Optimal aesthetic and functional outcomes with low recurrence rates can be achieved by using a multidisciplinary approach to complex dermal sarcomas. In cases of extended local tumour invasion in dermal sarcomas, advanced reconstructive techniques can be applied, and the interdisciplinary microsurgeon should be an integral part of the sarcoma board.

Role of Virus-Directed Therapy in Soft Tissue Sarcoma

OPINION STATEMENT

Bone and soft tissue sarcoma are rare cancers of mesenchymal origin with the characteristics of heterogeneity and diversity that account for less than 1% of solid malignant cancers. Conventional chemotherapy remains standard of care with response rates of 10-15% that are usually dependent on histologic subtype as some subtypes are chemotherapy resistant. There remains a large unmet clinical need for new and novel options promoting the development of promising therapeutic options such as immunotherapy. With more than 80 different subtypes, the heterogeneity of sarcoma requires thoughtful clinical trial design. In the sarcoma field, recent breakthroughs have occurred in the context of histology-specific approach based on underlying tumor biology. To that end, immunotherapy approaches will need to take a similar approach. Oncolytic viruses (OVs) have emerged as a promising treatment for many solid tumors and shown encouraging results in sarcoma. This review mainly focuses on collective clinical data highlighting the role of OVs as immunotherapy being used in soft tissue sarcoma (STS) and bone sarcomas. Combining OVs with T cell-activating checkpoint inhibition, adoptive cell therapy or targeted therapies may yield increased potency, improve antitumor efficacy of oncolytic virotherapy, and offer a new prospect for the treatment of sarcoma.

Retroperitoneal Sarcoma Care in 2021

Soft-tissue sarcomas are biologically heterogenous tumors arising from connective tissues with over 100 subtypes. Although sarcomas account for <1% of all adult malignancies, retroperitoneal sarcomas are a distinct subgroup accounting for <10% of all sarcomatous tumors. There have been considerable advancements in the understanding and treatment of retroperitoneal sarcoma in the last decade, with standard treatment consisting of upfront primary surgical resection. The evidence surrounding the addition of radiation therapy remains controversial. There remains no standard with regards to systemic therapy, including immunotherapy. Adjunctive therapy remains largely dictated by expert consensus and preferences at individual centers or participation in clinical trials. In this 2021 review, we detail the anatomical boundaries of the retroperitoneum, clinical characteristics, contemporary standard of care and well as recent advancements in retroperitoneal sarcoma care. Ongoing international collaborations are encouraged to advance our understanding of this complex disease.

Pharmacogenomics of soft tissue sarcomas: New horizons to understand efficacy and toxicity

Clinical responses to anticancer therapies in advanced soft tissue sarcoma (STS) are unfortunately limited to a small subset of patients. Much of the inter-individual variability in treatment efficacy and risk of toxicities is as result of polymorphisms in genes encoding proteins involved in drug pharmacokinetics and pharmacodynamics. Therefore, the detection of pharmacogenomics (PGx) biomarkers that might predict drug response and toxicity can be useful to explain the genetic basis for the differences in treatment efficacy and toxicity among STS patients. PGx markers are frequently located in transporters, drug-metabolizing enzyme genes, drug targets, or HLA alleles. Along this line, genetic variability harbouring in the germline genome of the patients can influence systemic pharmacokinetics and pharmacodynamics of the treatments, acting as predictive biomarkers for drug-induced toxicity and treatment efficacy. By linking drug activity to the functional complexity of cancer genomes, also systematic pharmacogenomic profiling in cancer cell lines and primary STS samples represents area of active investigation that could eventually lead to enhanced efficacy and offer a powerful biomarker discovery platform to optimize current treatments and improve the knowledge about the individual's drug response in STS patients into the clinical practice.

Landscape of Immune-Related Markers and Potential Therapeutic Targets in Soft Tissue Sarcoma

Simple Summary

Despite being a group of rare diseases of mesenchymal origin, soft tissue sarcomas are heterogenous and display varying clinical behavior, and depending on the subtype, intermediate- and high-grade sarcomas have significant metastatic potential, making it difficult to establish a standardized therapy. Our work, as well as studies by others, emphasizes the high potential of immunotherapy for the treatment of sarcoma. The aim of this study was to determine whether specific genomic alterations, as well as the expression of infiltrating cytotoxic and suppressive cell type markers identified by next-generation sequencing (NGS), warrant further consideration of immunotherapy agents for treating certain soft tissue sarcoma subtypes. Altogether, our data provide a better understanding of the immune composition of different sarcoma subtypes to better identify novel therapy targets.

Abstract

Soft tissue sarcomas, depending on the subtype and grade, frequently recur and become metastatic after localized treatment. There is now great interest in applying immunotherapy to sarcomas to immuno-profile the different subtypes and immune monitor for prognosis. Our group previously showed that key immunotherapy target genes are present in sarcomas. Here, we extend our findings by demonstrating that sarcomas with a relatively high mutational load are likely to be more sensitive to immunotherapy compared to sarcomas with a lower mutation load. We also show that sarcomas with a higher mutation load are associated with the expression of key immune-related genes. We found that CD8+ T cells are present in sarcoma subtypes and that PD-L2 is highly expressed. These findings further define potential mechanisms behind the immunotherapy response of specific sarcoma subtypes and can be used to develop more optimal treatments in the future.

A Deep Dive Into the Newest Avenues of Immunotherapy for Pediatric Osteosarcoma: A Systematic Review

Osteosarcoma (OS) is the most common primary bone cancer affecting children and young adults, most often occurring at the metaphysis of long bones. At present, treatment with combinations of surgery and chemotherapy for the localized OS has only brought minuscule improvements in prognosis. In comparison, the advanced, metastatic, or recurrent forms of OS are often non-responsive to chemotherapy, adding to the dire need to develop new and efficient therapies. The question of interest investigated in this systematic review is whether immunotherapy can play a meaningful role in improving the clinical outcomes of children with OS. This article aims to summarize the preclinical and clinical research conducted thus far on potential therapeutic avenues for pediatric OS using immunotherapy, including methods like checkpoint inhibition, adoptive cellular therapy with T-cells, chimeric antigen receptor T (CAR-T), and natural killer (NK) cells. It also highlights the influence of the innate and adaptive immune system on the tumor microenvironment, allowing for OS progression and metastasis. This systematic review contains 27 articles and analyses of multiple clinical trials employing immunotherapeutic drugs to 785 osteosarcoma participants and over 243 pediatric patients. The articles were obtained through PubMed, PubMed Central, and ClinicalTrials.gov and individually assessed for quality using the Assessment of Multiple Systematic Reviews (AMSTAR) checklist and the Cochrane risk-of-bias tool. The reviews reveal that immunotherapy's most significant impact on pediatric OS includes combining immune checkpoint blockers with traditional chemotherapy and surgery. However, due to the bimodal distribution of this aggressive malignancy, these studies cannot precisely estimate the overall effect and any potential life-threatening adverse events following therapy in children. Further research is required to fully assess the impact of these immunotherapies, including more extensive multinational clinical trials to focus on the pediatric population.

Targeted and immuno-based therapies in sarcoma: mechanisms and advances in clinical trials

Sarcomas represent a distinct group of rare malignant tumors with high heterogeneity. Limited options with clinical efficacy for the metastatic or local advanced sarcoma existed despite standard therapy. Recently, targeted therapy according to the molecular and genetic phenotype of individual sarcoma is a promising option. Among these drugs, anti-angiogenesis therapy achieved favorable efficacy in sarcomas. Inhibitors targeting cyclin-dependent kinase 4/6, poly-ADP-ribose polymerase, insulin-like growth factor-1 receptor, mTOR, NTRK, metabolisms, and epigenetic drugs are under clinical evaluation for sarcomas bearing the corresponding signals. Immunotherapy represents a promising and favorable method in advanced solid tumors. However, most sarcomas are immune "cold" tumors, with only alveolar soft part sarcoma and undifferentiated pleomorphic sarcoma respond to immune checkpoint inhibitors. Cellular therapies with TCR-engineered T cells, chimeric antigen receptor T cells, tumor infiltrating lymphocytes, and nature killer cells transfer show therapeutic potential. Identifying tumor-specific antigens and exploring immune modulation factors arguing the efficacy of these immunotherapies are the current challenges. This review focuses on the mechanisms, advances, and potential strategies of targeted and immune-based therapies in sarcomas.

Epigenetic strategies to boost CAR T cell therapy

Chimeric antigen receptor (CAR) T cell therapy has led to a paradigm shift in cancer immunotherapy, but still several obstacles limit CAR T cell efficacy in cancers. Advances in high-throughput technologies revealed new insights into the role that epigenetic reprogramming plays in T cells. Mechanistic studies as well as comprehensive epigenome maps revealed an important role for epigenetic remodeling in T cell differentiation. These modifications shape the overall immune response through alterations in T cell phenotype and function. Here, we outline how epigenetic modifications in CAR T cells can overcome barriers limiting CAR T cell effectiveness, particularly in immunosuppressive tumor microenvironments. We also offer our perspective on how selected epigenetic modifications can boost CAR T cells to ultimately improve the efficacy of CAR T cell therapy.

Self-defense of human sarcoma cells against cytolytic lymphoid cells of their host

Metastatic human sarcomas temporarily respond to radio-chemotherapy relapse and remain highly resistant to further combination chemotherapy as to a curative effect, including checkpoint control.

Primary Soft Tissue Sarcoma of the Heart: An Emerging Chapter in Cardio-Oncology

Primary malignant cardiac tumors are rare, with a prevalence of about 0.01% among all cancer histotypes. At least 60% of them are primary soft tissue sarcomas of the heart (pSTS-h) that represent almost 1% of all STSs. The cardiac site of origin is the best way to classify pSTS-h as it is directly linked to the surgical approach for cancer removal. Indeed, histological differentiation should integrate the classification to provide insights into prognosis and survival expectancy of the patients. The prognosis of pSTS-h is severe and mostly influenced by the primary localization of the tumor, the difficulty in achieving complete surgical and pharmacological eradication, and the aggressive biological features of malignant cells. This review aims to provide a detailed literature overview of the most relevant issues on primary soft tissue sarcoma of the heart and highlight potential diagnostic and therapeutic future perspectives.