Pembrolizumab in advanced soft-tissue sarcoma and bone sarcoma (SARC028): a multicentre, two-cohort, single-arm, open-label, phase 2 trial

Phase Ib Study for the Combination of Doxorubicin, Dacarbazine, and Nivolumab as the Upfront Treatment in Patients With Advanced Leiomyosarcoma: A Study by the Spanish Sarcoma Group (GEIS)

PURPOSE

Doxorubicin, alongside a select group of cytotoxic agents, is capable of inducing an adaptive immune response via a well-established peculiar type of tumor cell death called immunogenic cell death (ICD). We hypothesize that combining doxorubicin and dacarbazine with nivolumab may enhance therapeutic efficacy by exerting synergy in the ICD circuit. We hereby present a phase Ib trial with this combination.

PATIENTS AND METHODS

Patients with advanced leiomyosarcoma and anthracycline-naïve were eligible. The initial dose level consisted of doxorubicin 75 mg/m2 once on day 1, once every three weeks, followed by dacarbazine 400 mg/m2 once on days 1 and 2, once every three weeks, plus nivolumab 360 mg once on day 2, once every 3 weeks, for six courses and then 1 year of nivolumab. A (-1) dose level was the same regimen but with nivolumab 240 mg. A classic 3 + 3 phase-I design was used to determine the recommended phase-II dose (RP2D). Secondary end points included overall response rate, safety profile, survival, and translational research.

RESULTS

From January 2002 to July 2023, 24 patients were enrolled and 23 were evaluable for efficacy, excluding one patient because of noncompliant dose. All patients were treated with the initial dose level, then the RP2D. Toxicity was mild, with the most frequent being grade 4 toxicity neutropenia (16.7%) and thrombocytopenia (8.3%), while no grade 5 toxicity occurred. The centrally reviewed objective response rate was as follows: partial response 56.5%, stable disease 39.1%, and progression 4.4%. The 6-month progression-free survival (PFS) rate was 80% (95% CI, 63 to 98). Dynamic increases of HMGB1 in blood significantly correlated with longer PFS.

CONCLUSION

This scheme of doxorubicin, dacarbazine, and nivolumab is feasible and well tolerated. Clinical activity is encouraging and the prognostic impact of HMGB1 supports the relevance of ICD activation. Further clinical research is already underway with this concept in leiomyosarcoma.

Molecular markers of proliferation, DNA repair, and immune infiltration defines high-risk subset of resectable retroperitoneal sarcomas

INTRODUCTION

For retroperitoneal sarcomas (RPS), aggressive surgical resection offers the only chance for a cure; however, 5-year survival remains below 65%. Therefore, there is a critical need to identify drivers of poor clinical outcomes.

MATERIALS AND METHODS

To identify biomarkers of tumors likely to recur following curative intent resection, we performed genomic and transcriptomic sequencing for 47 and 34 patients, respectively, with non-metastatic RPS at a single, high-volume sarcoma center.

RESULTS

At the DNA level, alterations in TERT were associated with poor disease-free survival (DFS) and overall survival (OS). Increased RNA expression of gene sets related to growth signaling and DNA repair were associated with poor DFS and OS. Infiltration of CD8+ T-Cells and activated dendritic cells were associated with poor DFS and OS.

CONCLUSION

These findings may help to better identify and treat non-metastatic, high-risk RPS.

Osteosarcoma through the Lens of Bone Development, Signaling, and Microenvironment

In this work, we review the multifaceted connections between osteosarcoma (OS) biology and normal bone development. We summarize and critically analyze existing research, highlighting key areas that merit further exploration. The review addresses several topics in OS biology and their interplay with normal bone development processes, including OS cell of origin, genomics, tumor microenvironment, and metastasis. We examine the potential cellular origins of OS and how their roles in normal bone growth may contribute to OS pathogenesis. We survey the genomic landscape of OS, highlighting the developmental roles of genes frequently altered in OS. We then discuss the OS microenvironment, emphasizing the transformation of the bone niche in OS to facilitate tumor growth and metastasis. The role of stromal and immune cells is examined, including their impact on tumor progression and therapeutic response. We further provide insights into potential development-informed opportunities for novel therapeutic strategies.

Single-Cell Profiling of Sarcomas from Archival Tissue Reveals Programs Associated with Resistance to Immune Checkpoint Blockade

PURPOSE

Sarcoma encompasses a diverse group of cancers that are typically resistant to current therapies, including immune checkpoint blockade (ICB), and underlying mechanisms are poorly understood. The contexture of sarcomas limits generation of high-quality data using cutting-edge molecular profiling methods, such as single-cell RNA-sequencing, thus hampering progress in understanding these understudied cancers.

EXPERIMENTAL DESIGN

Here, we demonstrate feasibility of producing multimodal single-cell genomics and whole-genome sequencing data from frozen tissues, profiling 75,716 cell transcriptomes of five undifferentiated pleomorphic sarcoma and three intimal sarcoma samples, including paired specimens from two patients treated with ICB.

RESULTS

We find that genomic diversity decreases in patients with response to ICB, and, in unbiased analyses, identify cancer cell programs associated with therapy resistance. Although interactions of tumor-infiltrating T lymphocytes within the tumor ecosystem increase in ICB responders, clonal expansion of CD8+ T cells alone was insufficient to predict drug responses.

CONCLUSIONS

This study provides a framework for studying rare tumors and identifies salient and treatment-associated cancer cell intrinsic and tumor microenvironmental features in sarcomas.

Immune checkpoint markers and tumour mutation burden in Wilms tumour: a study of 59 cases

Wilms tumour (WT) is the most common renal tumour in children, and studies of immune checkpoint inhibitors (ICIs) treatment and markers are limited in number. In this study we investigated the ICIs' related immune landscape by examining the expression of PD-L1, PD-1, CD8 and DNA mismatch repair (MMR) proteins by immunohistochemistry (IHC), tumour mutation burden (TMB), and correlations with histology and clinical outcome. Positive PD-L1 (SP263) expression was defined as modified combined positive score (CPS) ≥1. A total of 59 WTs (from 2000 to 2017), including eight (14.0%) with anaplasia, from 46 patients were analysed (45 primary and 14 metastatic). Thirteen WTs (13/59, 22%) were positive for PD-L1 (8 primary, 5 metastatic; CPS 1.11-3.42). Positive PD-L1 expression was associated with diffuse anaplasia (p<0.05) and significantly shorter progression-free survival (p<0.05) among WTs with favourable histology (n=39). CD8+ lymphocytes were present in all analysed WTs. A subset of CD8+ cells co-expressed PD-1, which was associated with favourable histology and treatment. MMR IHC stains identified two (2/18, 11%) WTs with isolated PMS2 loss. All six WTs analysed for TMB showed low mutation burden. We found CD8+ lymphocytes in all analysed WTs and identified a fraction of WT (17.8% of primary and 35.8% of metastatic) with positive PD-L1 CPS, suggesting potential response to ICIs in some patients.

A multicenter, randomized, non-comparative, phase II study of nivolumab ± ipilimumab for patients with metastatic sarcoma (Alliance A091401): expansion cohorts and correlative analyses

BACKGROUND

In this open-label, randomized, non-comparative, multicenter phase II study (Alliance A091401) we report on three expansion cohorts treated with nivolumab (N) with and without ipilimumab (N+I) and provide a multi-omic correlative analysis of actionable biomarkers.

METHODS

Patients were randomized (non-comparative) to receive either N or N+I. The primary endpoint was a 6-month confirmed response rate (CRR) defined by Response Evaluation Criteria in Solid Tumors version 1.1. Secondary endpoints included treatment-related adverse events (TRAEs), progression-free survival, and overall survival. Multi-omic correlative analyses were conducted using samples from both the primary and expansion cohorts.

RESULTS

A total of 66 patients were evaluated for the primary endpoint with disease including gastrointestinal stromal tumor (GIST, n=18), undifferentiated pleomorphic sarcoma (UPS, n=24), and dedifferentiated liposarcoma (DDLPS, n=24). Neither N nor N+I achieved a complete or partial response in the GIST expansion cohort. In DDLPS and UPS, the primary response endpoint of CRR was met with N+I (both 16.6%, 2/12) but not with N alone (both 8.3%, 1/12). In the GIST cohort, TRAE was higher with N+I treatment, halting enrollment as required per protocol. In a correlative analysis of patients for the expansion cohort and the original cohort (n=86), traditional biomarkers of immunotherapy response were not correlated with response in any histological subtype. Markers of genomic instability including the presence of gene fusions and increased subclonal mutations correlated with improved clinical outcomes.

CONCLUSIONS

This expansion cohort reaffirms the outcomes of A091401. There remains a pressing need to determine the role of and predictive biomarkers for immunotherapy in sarcoma.

TRIAL REGISTRATION NUMBER

NCT02500797.

Spatial multiplexed immunofluorescence analysis reveals coordinated cellular networks associated with overall survival in metastatic osteosarcoma

Patients diagnosed with advanced osteosarcoma, often in the form of lung metastases, have abysmal five-year overall survival rates. The complexity of the osteosarcoma immune tumor microenvironment has been implicated in clinical trial failures of various immunotherapies. The purpose of this exploratory study was to spatially characterize the immune tumor microenvironment of metastatic osteosarcoma lung specimens. Knowledge of the coordinating cellular networks within these tissues could then lead to improved outcomes when utilizing immunotherapy for treatment of this disease. Importantly, various cell types, interactions, and cellular neighborhoods were associated with five-year survival status. Of note, increases in cellular interactions between T lymphocytes, positive for programmed cell death protein 1, and myeloid-derived suppressor cells were observed in the 5-year deceased cohort. Additionally, cellular neighborhood analysis identified an Immune-Cold Parenchyma cellular neighborhood, also associated with worse 5-year survival. Finally, the Osteosarcoma Spatial Score, which approximates effector immune activity in the immune tumor microenvironment through the spatial proximity of immune and tumor cells, was increased within 5-year survivors, suggesting improved effector signaling in this patient cohort. Ultimately, these data represent a robust spatial multiplexed immunofluorescence analysis of the metastatic osteosarcoma immune tumor microenvironment. Various communication networks, and their association with survival, were described. In the future, identification of these networks may suggest the use of specific, combinatory immunotherapeutic strategies for improved anti-tumor immune responses and outcomes in osteosarcoma.

Translation of oncolytic viruses in sarcoma

Sarcomas are a rare and highly diverse group of malignancies of mesenchymal origin. While sarcomas are generally considered resistant to immunotherapy, recent studies indicate subtype-specific differences in clinical response to checkpoint inhibitors (CPIs) that are associated with distinct immune phenotypes present in sarcoma subtypes. Oncolytic viruses (OVs) are designed to selectively infect and kill tumor cells and induce intratumoral immune infiltration, enhancing immunogenicity and thereby sensitizing tumors to immunotherapy. Herein we review the accumulated clinical data evaluating OVs in sarcoma. Small numbers of patients with sarcoma were enrolled in early-stage OV trials as part of larger solid tumor cohorts demonstrating safety but providing limited insight into the biological effects due to the low patient numbers and lack of histologic grouping. Several recent studies have investigated talimogene laherparepvec (T-VEC), an approved oncolytic herpes simplex virus (HSV-1), in combination therapy regimens in sarcoma patient cohorts. These studies have shown promising responses in heavily pre-treated and immunotherapy-resistant patients associated with increased intratumoral immune infiltration. As new and more potent OVs enter the clinical arena, prospective evaluation in subtype-specific cohorts with correlative studies to define biomarkers of response will be critical to advancing this promising approach for sarcoma therapy.

Advancing treatment efficacy: combined therapy of eribulin, anlotinib, and camrelizumab in advanced or metastatic retroperitoneal liposarcoma

Background

Retroperitoneal liposarcoma (RLPS) typically shows limited response to standard chemotherapy, presenting a challenge in treating advanced or metastatic RLPS.

Objective

This study aimed to evaluate the potential advantages of a combined therapeutic strategy utilizing eribulin, anlotinib, and camrelizumab.

Design

Between December 2020 and March 2023, this retrospective study enrolled patients with advanced or metastatic RLPS who received treatment at Peking University Cancer Hospital Sarcoma Center. The treatment regimen involved eribulin plus anlotinib and camrelizumab administered every 3 weeks (Q3W).

Methods

Efficacy was assessed following the Response Evaluation Criteria in Solid Tumors version 1.1, while safety was evaluated using the Common Terminology Criteria for Adverse Events version 5.0.

Results

The study included 47 patients with RLPS with a median age of 55.5 years. Patients received a median of 4.5 (range, 2-21) cycles of treatment. Notably, partial response was observed in 8 patients (18.2%), while 25 (56.8%) exhibited stable disease. The objective response rate (ORR) and disease control rate were 18.2% and 75%, respectively. Significant differences in ORR were observed among histological subtypes (well-differentiated vs de-differentiated vs myxoid: 0 vs 17.9% vs 50%; p = 0.039). Six patients underwent surgery before disease progression, and one patient with myxoid liposarcoma (MLPS) had a pathological complete response. With a median follow-up of 21.8 (range, 2.7-30.7) months, the median progression-free survival (mPFS) was 6.9 (95% confidence interval (CI), 4.7-9.1) months, and the 6-month PFS rate was 60.5%. Based on various histological subtypes, the mPFS was 8.4 (95% CI, 4.1-12.7) months with well-differentiated liposarcoma, 5.8 (95% CI, 3.3-8.3) months with de-differentiated liposarcoma and not reached with MLPS, respectively. Treatment-related adverse events (TRAEs) of any grade occurred in 36 (76.6%) patients, with grade 3 or higher TRAEs in 21 (44.7%) patients. The most common TRAEs were neutropenia (53.2%), proteinuria (21.3%), and anorexia (21.3%).

Conclusion

The combined treatment strategy involving eribulin, anlotinib, and camrelizumab showed promising efficacy and manageable safety in patients with advanced or metastatic RLPS, particularly in those with MLPS.

Molecular Profiling Defines Three Subtypes of Synovial Sarcoma

Synovial Sarcomas (SS) are characterized by the presence of the SS18::SSX fusion gene, which protein product induce chromatin changes through remodeling of the BAF complex. To elucidate the genomic events that drive phenotypic diversity in SS, we performed RNA and targeted DNA sequencing on 91 tumors from 55 patients. Our results were verified by proteomic analysis, public gene expression cohorts and single-cell RNA sequencing. Transcriptome profiling identified three distinct SS subtypes resembling the known histological subtypes: SS subtype I and was characterized by hyperproliferation, evasion of immune detection and a poor prognosis. SS subtype II and was dominated by a vascular-stromal component and had a significantly better outcome. SS Subtype III was characterized by biphasic differentiation, increased genomic complexity and immune suppression mediated by checkpoint inhibition, and poor prognosis despite good responses to neoadjuvant therapy. Chromosomal abnormalities were an independent significant risk factor for metastasis. KRT8 was identified as a key component for epithelial differentiation in biphasic tumors, potentially controlled by OVOL1 regulation. Our findings explain the histological grounds for SS classification and indicate that a significantly larger proportion of patients have high risk tumors (corresponding to SS subtype I) than previously believed.

Advances on immunotherapy for osteosarcoma

Osteosarcoma is the most common primary bone cancer in children and young adults. Limited progress has been made in improving the survival outcomes in patients with osteosarcoma over the past four decades. Especially in metastatic or recurrent osteosarcoma, the survival rate is extremely unsatisfactory. The treatment of osteosarcoma urgently needs breakthroughs. In recent years, immunotherapy has achieved good therapeutic effects in various solid tumors. Due to the low immunogenicity and immunosuppressive microenvironment of osteosarcoma, immunotherapy has not yet been approved in osteosarcoma patients. However, immune-based therapies, including immune checkpoint inhibitors, chimeric antigen receptor T cells, and bispecfic antibodies are in active clinical development. In addition, other immunotherapy strategies including modified-NK cells/macrophages, DC vaccines, and cytokines are still in the early stages of research, but they will be hot topics for future study. In this review, we showed the functions of cell components including tumor-promoting and tumor-suppressing cells in the tumor microenvironment of osteosarcoma, and summarized the preclinical and clinical research results of various immunotherapy strategies in osteosarcoma, hoping to provide new ideas for future research in this field.

Brief Communication on MAGE-A4 and Coexpression of Cancer Testis Antigens in Metastatic Synovial Sarcomas: Considerations for Development of Immunotherapeutics

Therapeutic options for synovial sarcoma (SyS) have not evolved for several decades and the efficacy of second-line treatments is very limited. The expression of a large family of proteins known as cancer testis antigens (CTAs) in SyS has spurred the development of targeted T-cell therapies currently in clinical trials, such as those aimed at melanoma-associated antigen (MAGE)-A4 and New York esophageal squamous cell carcinoma 1 (NY-ESO-1), which have shown promising clinical efficacy. Extensive knowledge of the prevalence of expression and coexpression of CTAs is critical to design T-cell therapies with optimal coverage of the patient population. We analyzed the expression of CTAs of the MAGE-A family as well as NY-ESO-1 and preferentially expressed antigen in melanoma (PRAME) by RNA sequencing in a large cohort of 133 SyS samples from patients registered in the French sarcoma database (NETSARC+). Among MAGE-As, MAGE-A4 had the highest prevalence (65%), followed by MAGE-A10 (15%) and MAGE-A9 (13%). Almost all samples (92%) expressing any of the MAGE-As also expressed MAGE-A4. NY-ESO-1 was expressed in 65% of samples, with a large but incomplete overlap with MAGE-A4, whereas PRAME was present in 121 (91%) samples. Complementary immunohistochemical analyses were used to establish the positive correlation between RNA and protein expression for MAGE-A4 and NY-ESO-1. These data inform the strategy for optimal coverage of the SyS patient population with T-cell therapies, offering patients with SyS new options for single or combined second lines of treatment.

Progress in histology specific treatments in soft tissue sarcoma

INTRODUCTION

Soft tissue sarcomas (STS) represent a heterogenous group of rare tumors, primarily treated with surgery. Preoperative radiotherapy is often recommended for extremity high-risk STS. Neoadjuvant chemotherapy, typically based on doxorubicin with ifosfamide, has shown efficacy in limbs and trunk wall STS. Second-line chemotherapy, commonly utilized in the metastatic setting, is mostly histology-driven. Molecular targeted agents are used across various histologies, and although the use of immunotherapy in STS is still in its early stages, there is increasing interest in exploring its potential.

AREAS COVERED

This article involved an extensive recent search on PubMed. It explored the current treatment landscape for localized and metastatic STS, focusing on the combined use of radiotherapy and chemotherapy for both extremity and retroperitoneal tumors, and with a particular emphasis on the most innovative histopathology driven therapeutic approaches. Additionally, ongoing clinical trials identified via clinicaltrials.gov are included.

EXPERT OPINION

Recently there have been advancements in the treatment of STS, largely driven by the outcomes of clinical trials. However further research is imperative to comprehend the effect of chemotherapy, targeted therapy and immunotherapy in various STS, as well as to identify biomarkers able to predict which patients are most likely to benefit from these treatments.

Camrelizumab in combination with doxorubicin, cisplatin, ifosfamide, and methotrexate in neoadjuvant treatment of resectable osteosarcoma: A prospective, single-arm, exploratory phase II trial

BACKGROUND

The poor overall survival of osteosarcoma (OS) underscores the need to explore new therapeutic avenues. Tumor necrosis rate (TNR) after neoadjuvant chemotherapy predicts prognosis.

AIMS

The study was to investigate safety and activity of neoadjuvant chemotherapy with camrelizumab (a humanized antibody against PD-1) in patients with resectable OS.

MATERIALS & METHODS

We conducted a prospective, single-arm, exploratory phase II trial in OS patients. Eligible patients received camrelizumab combined with doxorubicin or liposomal doxorubicin, cisplatin, methotrexate, ifosfamide with mesna. Surgery was performed 12-14 days after neoadjuvant therapy and adjuvant therapy starting 2-3 weeks postoperatively. The primary endpoint was the rate of good tumor necrosis (TNR ≥90%) after neoadjuvant therapy, and the secondary outcomes were safety, 2-year progression free survival and 2-year overall survival.

RESULTS

Seventy-five patients were recruited to the study. Subsequently, 64 patients completed neoadjuvant therapy and underwent surgery. Thirty-one patients (48.4%) have a good TNR to neoadjuvant therapy. With a median follow-up of 22.4 months (range 2.2-44.9 months), the estimated 2-year PFS was 69.6% and the estimated 2-year overall survival was 89.4%. Grade 3 or 4 treatment-related adverse events were noticed in 62.7% of the patients. Frequent grade 3 or 4 adverse events were decreased platelet count (45.3%), decreased white blood cell count (36%). No immune-related serious adverse events were observed.

DISCUSSION

Our study had limitations. First, it was limited by its non-randomized design. Besides, stromal tumor-infiltrating lymphocytes was comprehensively analyzed in this study.

CONCLUSIONS

This study demonstrated that amrelizumab combined with adriamycin, cisplatin, methotrexate, and ifosfamide in the neoadjuvant treatment of resectable OS was safe and tolerable. This combined therapeutic strategy may not increase TNR, but the long-term survival benefit remains to be followed up.

Molecular characteristics and systemic treatment options of liposarcoma: A systematic review

Liposarcoma (LPS) is a rare soft tissue sarcoma that develops from the differentiation of fat cells, typically occurring in the lower extremities and retroperitoneal space. Depending on its histological morphology and molecular changes, LPS can be divided into various subtypes, each exhibiting distinct biological behaviors. During treatment, especially for LPS arising in the retroperitoneum, the extent and quality of the initial surgery are critically important. Treatment strategies must be tailored to the specific type of LPS. Over the past few decades, the treatment of LPS has undergone numerous advancements, with new therapeutic approaches such as targeted drugs and immunotherapies continually emerging. This paper reviews the biological characteristics, molecular alterations, as well as surgical and pharmacological treatments of various LPS subtypes, with the aim of enhancing clinicians' understanding and emphasizing the importance of individualized precision therapy. With a deeper understanding of the biological characteristics and molecular alterations of LPS, future treatment trends are likely to focus more on developing personalized treatment plans to better address the various types of LPS.

Pediatric Leukemia Roadmaps Are a Guide for Positive Metastatic Bone Sarcoma Trials

ALL cures require many MRD therapies. This strategy should drive experiments and trials in metastatic bone sarcomas.

Toward a comprehensive solution for treating solid tumors using T-cell receptor therapy: A review

T-cell receptor therapy (TCR-T) has demonstrated efficacy, durability, and safety advantages in certain solid tumors (such as human papillomavirus-related tumors, synovial sarcoma, and melanoma). This study aimed to provide careful considerations for developing TCR-T for solid tumors. Therefore, in this review, we have summarized the current clinical application, advantage of TCR-T modalities and explored efficacy/safety-related parameters, particularly avidity, pharmacokinetics/pharmacodynamics, and indications, for solid tumors. Furthermore, we have investigated critical factors related to avidity, including antigen selection, T-cell receptor acquisition, optimization, and co-receptor engagement. Moreover, we have re-examined the expression of tumor antigens for a potentially higher coverage rate of solid tumors based on the current RNA-seq datasets. Finally, we have discussed the current limitations and future directions of TCR-Ts.

Prognostic Signature in Osteosarcoma Based on Amino Acid Metabolism-Associated Genes

Background: Osteosarcoma (OS) is undeniably a formidable bone malignancy characterized by a scarcity of effective treatment options. Reprogramming of amino acid (AA) metabolism has been associated with OS development. The present study was designed to identify metabolism-associated genes (MAGs) that are differentially expressed in OS and to construct a MAG-based prognostic risk signature for this disease. Methods: Expression profiles and clinicopathological data were downloaded from Gene Expression Omnibus (GEO) and UCSC Xena databases. A set of AA MAGs was obtained from the MSigDB database. Differentially expressed genes (DEGs) in GEO dataset were identified using "limma." Prognostic MAGs from UCSC Xena database were determined through univariate Cox regression and used in the prognostic signature development. This signature was validated using another dataset from GEO database. Gene Ontology, Kyoto Encyclopedia of Genes and Genomes, single sample gene set enrichment analysis, and GDSC2 analyses were performed to explore the biological functions of the MAGs. A MAG-based nomogram was established to predict 1-, 3-, and 5-year survival. Real-time quantitative polymerase chain reaction, Western blot, and immunohistochemical staining confirmed the expression of MAGs in primary OS and paired adjacent normal tissues. Results: A total of 790 DEGs and 62 prognostic MAGs were identified. A MAG-based signature was constructed based on four MAGs: PIPOX, PSMC2, SMOX, and PSAT1. The prognostic value of this signature was successfully validated, with areas under the receiver operating characteristic curves for 1-, 3-, and 5-year survival of 0.714, 0.719, and 0.715, respectively. This MAG-based signature was correlated with the infiltration of CD56dim natural killer cells and resistance to several antiangiogenic agents. The nomogram was accurate in predictions, with a C-index of 0.77. The expression of MAGs verified by experiment was consistent with the trends observed in GEO database. Conclusion: Four AA MAGs were prognostic of survival in OS patients. This MAG-based signature has the potential to offer valuable insights into the development of treatments for OS.

Enhanced Osteosarcoma Immunotherapy via CaCO3 Nanoparticles: Remodeling Tumor Acidic and Immune Microenvironment for Photodynamic Therapy

Osteosarcoma (OS) is a "cold" tumor enriched in noninflammatory M2 phenotype tumor-associated macrophages (TAMs), which limits the efficacy of immunotherapy. The acidic tumor microenvironment (TME), generated by factors such as excess hydrogen (H+) ions and high lactate levels, activates immunosuppressive cells, further promoting a suppressive tumor immune microenvironment (TIME). Therefore, a multitarget synergistic combination strategy that neutralizes the acidic TME and reprograms TAMs can be beneficial for OS therapy. Here, a calcium carbonate (CaCO3)/polydopamine (PDA)-based nanosystem (A-NPs@(SHK+Ce6)) is developed. CaCO3 nanoparticles are used to neutralize H+ ions and alleviate the suppressive TIME, and the loaded SHK not only synergizes with photodynamic therapy (PDT) but also inhibits lactate production, further reversing the acidic TME and repolarizing TAMs to consequently lead to enhanced PDT-induced tumor suppression and comprehensive beneficial effects on antitumor immune responses. Importantly, A-NPs@(SHK+Ce6), in combination with programmed cell death protein 1 (PD-1) checkpoint blockade, shows a remarkable ability to eliminate distant tumors and promote long-term immune memory function to protect against rechallenged tumors. This work presents a novel multiple-component combination strategy that coregulates the acidic TME and TAM polarization to reprogram the TIME.

Mesenchymal Tumor Management: Integrating Surgical and Non-Surgical Strategies in Different Clinical Scenarios

Mesenchymal tumors originate from mesenchymal cells and can be either benign or malignant, such as bone, soft tissue, and visceral sarcomas. Surgery is a cornerstone treatment in the management of mesenchymal tumors, often requiring complex procedures performed in high-volume referral centers. However, the COVID-19 pandemic has highlighted this need for alternative non-surgical approaches due to limited access to surgical resources. This review explores the role of non-surgical treatments in different clinical scenarios: for improving surgical outcomes, as a bridge to surgery, as better alternatives to surgery, and for non-curative treatment when surgery is not feasible. We discuss the effectiveness of active surveillance, cryoablation, high-intensity focused ultrasound, and other ablative techniques in managing these tumors. Additionally, we examine the use of tyrosine kinase inhibitors in gastrointestinal stromal tumors and hypofractionated radiotherapy in soft tissue sarcomas. The Sarculator tool is highlighted for its role in stratifying high-risk sarcoma patients and personalizing treatment plans. While surgery remains the mainstay of treatment, integrating advanced non-surgical strategies can enhance therapeutic possibilities and patient care, especially in specific clinical settings with limitations. A multidisciplinary approach in referral centers is vital to determine the optimal treatment course for each patient.

Real-world efficacy, safety data and predictive clinical parameters for treatment outcomes in advanced soft tissue sarcoma treated with combined immunotherapy and antiangiogenic therapy

BACKGROUND

The combination of immunotherapy and antiangiogenic therapy has shown potential in the treatment of numerous malignant tumors, but limited evidence was available for soft tissue sarcomas (STS). Therefore, the aim of the present study is to assess the efficacy and safety of immunotherapy in conjunction with antiangiogenic therapy in patients diagnosed with advanced STS (aSTS).

METHODS

The study enrolled patients with aSTS from January 2014 to October 2022. Eligible participants had previously received anthracycline-based chemotherapy, presented with an anthracycline-resistant sarcoma subtype, or were ineligible for anthracycline treatment due to medical conditions. Following enrollment, these patients received a combination of immunotherapy and antiangiogenic therapy. The primary endpoints were the objective response rate (ORR) and progression-free survival (PFS), while the secondary endpoints included the disease control rate (DCR), overall survival (OS), and the incidence of adverse events.

RESULTS

Fifty-one patients were included in this cohort study. The median duration of follow-up was 15.8 months. The ORR and DCR were 17.6%, and 76.5%, respectively. The median PFS (mPFS) was 5.8 months (95% CI: 4.8-6.8) for all patients, and the median OS had not been reached as of the date cutoff. Multivariate analysis indicated that Eastern Cooperative Oncology Group performance status of 0-1 and ≤ second-line treatment were positive predictors for both PFS and OS. Patients with alveolar soft part sarcoma or clear cell sarcoma had longer mPFS (16.2 months, 95% CI: 7.8-25.6) when compared to those with other subtypes of STS (4.4 months, 95% CI: 1.4-7.5, P < 0.001). Among the observed adverse events, hypertension (23.5%), diarrhea (17.6%), and proteinuria (17.6%) were the most common, with no treatment-related deaths reported.

CONCLUSION

The combination of immunotherapy and antiangiogenic agents showed promising efficacy and acceptable toxicity in patients with aSTS, especially those with alveolar soft part sarcoma or clear cell sarcoma.

Jejunal sarcomatoid carcinoma: A case report and review of literature

BACKGROUND

Sarcomatoid carcinoma (SCA) of the jejunum is a rare and aggressive neoplasm affecting the smooth muscle cells of the jejunum. This study presents a recent case of jejunal SCA, detailing its diagnosis and treatment, thereby providing a reference for clinical practice.

CASE SUMMARY

A 65-year-old male presented to Yichang Central People's Hospital with a chief complaint of hemorrhoids. A computed tomography (CT) scan incidentally revealed multiple abnormal signals in the liver. Subsequent positron emission tomography/CT at Wuhan Union Hospital indicated malignant tumor progression, with a primary duodenal tumor and multiple metastases in the upper left abdomen. Intraoperatively, a large tumor was identified on the omentum. Histopathological and immunohistochemical analyses of the resected specimen confirmed the diagnosis of jejunal SCA. The patient received a combination therapy of sintilimab, nanoparticle albumin-bound paclitaxel, and anlotinib. Follow-up imaging demonstrated significant reduction of hepatic and peritoneal lesions. The patient has remained stable for over one year postoperatively.

CONCLUSION

This case suggests that chemotherapy, immunotherapy, plus targeted therapy may represent an optimal treatment for intestinal SCA, meriting further investigation.

Global research development of chondrosarcoma from 2003 to 2022: a bibliometric analysis

Background

Chondrosarcomas are common primary malignant bone tumors; however, comprehensive bibliometric analysis in this field has not yet been conducted. Therefore, this study aimed to explore the research hotspots and trends in the field of chondrosarcoma through bibliometric analysis to help researchers understand the current status and direction of research in the field.

Methods

Articles and reviews related to chondrosarcoma published between 2003 and 2022 were retrieved from the Web of Science. Countries, institutions, authors, journals, references, and keywords in this field were visualized and analyzed using CtieSpace and VOSviewer software.

Results

Between 2003 and 2022, 4,149 relevant articles were found. The number of articles published on chondrosarcoma has increased significantly annually, mainly from 569 institutions in China and the United States, and 81 in other countries. In total, 904 authors participated in the publication of studies related to chondrosarcomas. Over the past 20 years, articles on chondrosarcoma have been published in 958 academic journals, with Skeletal Radiology having the highest number of publications. Furthermore, keywords such as "gene expression," "radiotherapy," "experience," and "apoptosis" have been popular in recent years.

Conclusion

Over the past 20 years, the global trend in chondrosarcoma research has primarily been clinical research, with basic research as a supplement. In the future, communication and exchange between countries and institutions should be strengthened. Further, the future main research hotspots in the field of chondrosarcoma include mutated genes and signaling pathways, precision surgical treatment, proton therapy, radiation therapy, chemotherapy, immunotherapy, and other aspects.

Spatial distribution of tumour immune infiltrate predicts outcomes of patients with high-risk soft tissue sarcomas after neoadjuvant chemotherapy

BACKGROUND

Anthracycline-based neoadjuvant chemotherapy (NAC) may modify tumour immune infiltrate. This study characterized immune infiltrate spatial distribution after NAC in primary high-risk soft tissue sarcomas (STS) and investigate association with prognosis.

METHODS

The ISG-STS 1001 trial randomized STS patients to anthracycline plus ifosfamide (AI) or a histology-tailored (HT) NAC. Four areas of tumour specimens were sampled: the area showing the highest lymphocyte infiltrate (HI) at H&E; the area with lack of post-treatment changes (highest grade, HG); the area with post-treatment changes (lowest grade, LG); and the tumour edge (TE). CD3, CD8, PD-1, CD20, FOXP3, and CD163 were analyzed at immunohistochemistry and digital pathology. A machine learning method was used to generate sarcoma immune index scores (SIS) that predict patient disease-free and overall survival (DFS and OS).

FINDINGS

Tumour infiltrating lymphocytes and PD-1+ cells together with CD163+ cells were more represented in STS histologies with complex compared to simple karyotype, while CD20+ B-cells were detected in both these histology groups. PD-1+ cells exerted a negative prognostic value irrespectively of their spatial distribution. Enrichment in CD20+ B-cells at HI and TE areas was associated with better patient outcomes. We generated a prognostic SIS for each tumour area, having the HI-SIS the best performance. Such prognostic value was driven by treatment with AI.

INTERPRETATION

The different spatial distribution of immune populations and their different association with prognosis support NAC as a modifier of tumour immune infiltrate in STS.

FUNDING

Pharmamar; Italian Ministry of Health [RF-2019-12370923; GR-2016-02362609]; 5 × 1000 Funds-2016, Italian Ministry of Health; AIRC Grant [ID#28546].

An Overview of Cancer Biology, Pathophysiological Development and It's Treatment Modalities: Current Challenges of Cancer anti-Angiogenic Therapy

A number of conditions and factors can cause the transformation of normal cells in the body into malignant tissue by changing the normal functions of a wide range of regulatory, apoptotic, and signal transduction pathways. Despite the current deficiency in fully understanding the mechanism of cancer action accurately and clearly, numerous genes and proteins that are causally involved in the initiation, progression, and metastasis of cancer have been identified. But due to the lack of space and the abundance of details on this complex topic, we have emphasized here more recent advances in our understanding of the principles implied tumor cell transformation, development, invasion, angiogenesis, and metastasis. Inhibition of angiogenesis is a significant strategy for the treatment of various solid tumors, that essentially depend on cutting or at least limiting the supply of blood to micro-regions of tumors, leading to pan-hypoxia and pan-necrosis inside solid tumor tissues. Researchers have continued to enhance the efficiency of anti-angiogenic drugs over the past two decades, to identify their potential in the drug interaction, and to discover reasonable interpretations for possible resistance to treatment. In this review, we have discussed an overview of cancer history and recent methods use in cancer therapy, focusing on anti-angiogenic inhibitors targeting angiogenesis formation. Further, this review has explained the molecular mechanism of action of these anti-angiogenic inhibitors in various tumor types and their limitations use. In addition, we described the synergistic mechanisms of immunotherapy and anti-angiogenic therapy and summarizes current clinical trials of these combinations. Many phase III trials found that combining immunotherapy and anti-angiogenic therapy improved survival. Therefore, targeting the source supply of cancer cells to grow and spread with new anti-angiogenic agents in combination with different conventional therapy is a novel method to reduce cancer progression. The aim of this paper is to overview the varying concepts of cancer focusing on mechanisms involved in tumor angiogenesis and provide an overview of the recent trends in anti-angiogenic strategies for cancer therapy.

Enhanced pyroptosis induction with pore-forming gene delivery for osteosarcoma microenvironment reshaping

Osteosarcoma is the most common malignant bone tumor without efficient management for improving 5-year event-free survival. Immunotherapy is also limited due to its highly immunosuppressive tumor microenvironment (TME). Pore-forming gasdermins (GSDMs)-mediated pyroptosis has gained increasing concern in reshaping TME, however, the expressions and relationships of GSDMs with osteosarcoma remain unclear. Herein, gasdermin E (GSDME) expression is found to be positively correlated with the prognosis and immune infiltration of osteosarcoma patients, and low GSDME expression was observed. A vector termed as LPAD contains abundant hydroxyl groups for hydrating layer formation was then prepared to deliver the GSDME gene to upregulate protein expression in osteosarcoma for efficient TME reshaping via enhanced pyroptosis induction. Atomistic molecular dynamics simulations analysis proved that the hydroxyl groups increased LPAD hydration abilities by enhancing coulombic interaction. The upregulated GSDME expression together with cleaved caspase-3 provided impressive pyroptosis induction. The pyroptosis further initiated proinflammatory cytokines release, increased immune cell infiltration, activated adaptive immune responses and create a favorable immunogenic hot TME. The study not only confirms the role of GSDME in the immune infiltration and prognosis of osteosarcoma, but also provides a promising strategy for the inhibition of osteosarcoma by pore-forming GSDME gene delivery induced enhanced pyroptosis to reshape the TME of osteosarcoma.

Modulating tumor-associated macrophage polarization by anti-maRCO mAb exerts anti-osteosarcoma effects through regulating osteosarcoma cell proliferation, migration and apoptosis

PURPOSE

Osteosarcoma is a primary bone tumor lacking optimal clinical treatment options. Tumor-associated macrophages in the tumor microenvironment are closely associated with tumor development and metastasis. Studies have identified the macrophage receptor with collagenous structure (MARCO) as a specific receptor expressed in macrophages. This study aimed to investigate whether anti-MARCO mAb treatment can induce macrophage polarization in the tumor microenvironment and elicit anti-tumor effects.

METHODS

THP-1 cells were treated with 20 ng/mL phorbol 12-myristate 13-acetate and 80 ng/mL interleukin-4 for 48 h to induce macrophage polarization to alternatively activated macrophages (M2). Enzyme-linked immunosorbent assay, real-time quantitative polymerase chain reaction, flow cytometry, and bioinformatic analyses were performed to evaluate macrophage polarization. The co-culture groups included a blank group, an M2 macrophage and U2OS co-culture group, and an anti-MARCO mAb-treated M2 macrophage group. Cell viability assays, cell scratch tests, apoptosis, and cell cycle analyses were performed to determine the effects of anti-MARCO mAb-treated macrophages on osteosarcoma cells.

RESULTS

It was demonstrated that anti-MARCO mAb can drive macrophages toward classically activated macrophage (M1) polarization. Anti-MARCO mAb promoted the secretion of pro-inflammatory factors by macrophages, including tumor necrosis factor-alpha (TNF-α), interleukin-1beta, interleukin-6 and interleukin-23. Studies on in vitro co-culture models have revealed that macrophages treated with anti-MARCO mAb can suppress the growth and migration of osteosarcoma cells, induce cell apoptosis, and inhibit cell cycle progression of osteosarcoma cells through M1 polarization of macrophages in vitro.

CONCLUSION

Anti-MARCO mAb treatment exerts anti-osteosarcoma effects by affecting macrophage polarization toward M1 macrophages, offering a potential new therapeutic approach for treating osteosarcoma.

Desmoplastic small round cell tumor: from genomics to targets, potential paths to future therapeutics

Desmoplastic Small Round Cell Tumor (DSRCT) is a highly aggressive pediatric cancer caused by a reciprocal translocation between chromosomes 11 and 22, leading to the formation of the EWSR1::WT1 oncoprotein. DSRCT presents most commonly in the abdominal and pelvic peritoneum and remains refractory to current treatment regimens which include chemotherapy, radiotherapy, and surgery. As a rare cancer, sample and model availability have been a limiting factor to DSRCT research. However, the establishment of rare tumor banks and novel cell lines have recently propelled critical advances in the understanding of DSRCT biology and the identification of potentially promising targeted therapeutics. Here we review model and dataset availability, current understanding of the EWSR1::WT1 oncogenic mechanism, and promising preclinical therapeutics, some of which are now advancing to clinical trials. We discuss efforts to inhibit critical dependencies including NTRK3, EGFR, and CDK4/6 as well as novel immunotherapy strategies targeting surface markers highly expressed in DSRCT such as B7-H3 or neopeptides either derived from or driven by the fusion oncoprotein. Finally, we discuss the prospect of combination therapies and strategies for prioritizing clinical translation.

Case report: A case of primary renal osteosarcoma

RATIONALE

Primary renal osteosarcoma is an exceedingly rare malignant tumor. Fewer than 30 cases have been reported in the literature since 1936. Furthermore, it has a high risk of metastasis and a poor overall prognosis rate.

PATIENTS CONCERNS

In this report, we present a case of osteosarcoma originating from the left kidney (21 cm × 18 cm × 11 cm) with adhesions of the descending colon mesentery and the abdominal wall. A 63-year-old male patient presented with flank pain and gross hematuria.

DIAGNOSES

A computed tomography scan revealed that the lesion with irregular margins was observed at the lower pole of the left kidney. Enhanced CT scan showed significant inhomogeneous enhancement of the lesion, with non-enhancing necrotic areas. A radical nephrectomy was performed. The immunohistochemistry results support the diagnosis of osteosarcoma.

INTERVENTIONS

Postoperatively, the patient participated in clinical trials and received treatment with a PD-1 antibody (2 weeks/once).

OUTCOMES

At the one-year follow-up, the patient reported late-stage systemic cancer-related pain, necessitating daily pain relief medication. Unfortunately, the patient passed away 18 months after the surgery.

LESSONS

The case reported here is an exceedingly rare malignant osteosarcoma that originated from the kidney with the invasion of the descending colon mesentery and the abdominal wall. The patient received treatment with a PD-1 antibody (2 weeks/once). However, the patient passed away 18 months after the surgery. With the application of genetic testing technology and advancements in molecular biology, it was expected that specific targeted therapies for this condition would emerge in the future.

Treatment of intracranial inflammatory myofibroblastic tumor with PD-L1 inhibitor and novel oncolytic adenovirus Ad-TD-nsIL12: a case report and literature review

Inflammatory myofibroblastic tumor (IMT) is a rare pathological entity first described in 1939. This lesion is most commonly found in the lungs, but cases involving other systems, such as the central nervous system known as intracranial IMT (IIMT), have also been reported. Diagnosis currently relies on pathological results due to the lack of characteristic imaging changes. Surgical resection is an effective treatment, though the disease is invasive and may recur. Previous literature has reported a high level of programmed death 1 (PD-1) expression in IMT tissues, suggesting that immunotherapy may be effective for this condition. In this case report, we present a middle-aged male who received PD-1 inhibitor and oncolytic adenovirus (Ad-TD-nsIL12) treatment after IIMT resection surgery. This successful approach provides a new direction for the treatment of IIMT.

Potentially actionable targets in synovial sarcoma: A tissue microarray study

BACKGROUND

Synovial sarcoma (SynSa) is one of the most common translocation-related soft tissue sarcomas. Patients with metastatic SynSa have limited treatment options and a very poor prognosis. Several novel experimental therapies are currently being explored in clinical trials, including T cell-based therapies targeting cancer testis antigens such as New York esophageal squamous cell carcinoma 1 (NY-ESO-1) or melanoma-associated antigen A4 (MAGE-A4), and degraders targeting bromodomain-containing protein 9 (BRD9). Preclinical studies investigate inhibitors of Yes associated protein 1 (YAP1), transcriptional co-activator with PDZ-binding motif (TAZ) and inhibitors of chemokine receptor 4 (CXCR4).

METHODS

We explored the immunohistochemical expression of these targets using a tissue microarray (TMA) constructed from 91 clinical SynSa samples and correlated these findings with corresponding clinicopathological data.

RESULTS

Expression of MAGE-A4 and NY-ESO-1 was found in 69 % and 56 % of the samples, respectively. NY-ESO-1 was statistically higher expressed in samples from metastatic lesions as compared to samples from primary tumors. Nuclear expression of YAP1 and TAZ was observed in 92 % and 51 % of the samples, respectively. CXCR4 was expressed in the majority of the samples (82 %). BRD9 was highly expressed in all specimens. No prognostic role could be identified for any of the investigated proteins.

CONCLUSION

This study is a comprehensive study providing real-world data on the expression of several actionable proteins in a large proportion of SynSa samples. All evaluated markers were expressed in a clinically meaningful proportion of cases represented in our TMA, supporting the relevance of ongoing preclinical and clinical research with novel agents directed against these targets.

Oncolytic Viral Therapy in Osteosarcoma

Primary bone malignancies, including osteosarcoma (OS), are rare but aggressive. Current OS treatment, involving surgical resection and chemotherapy, has improved survival for non-metastatic cases but remains ineffective for recurrent or metastatic OS. Oncolytic viral therapy (OVT) is a promising alternative, using naturally occurring or genetically modified viruses to selectively target and lyse cancer cells and induce a robust immune response against remaining OS cells. Various oncolytic viruses (OVs), such as adenovirus, herpes simplex virus, and measles virus, have demonstrated efficacy in preclinical OS models. Combining OVT with other therapeutics, such as chemotherapy or immunotherapy, may further improve outcomes. Despite these advances, challenges in reliability of preclinical models, safety, delivery, and immune response must be addressed to optimize OVT for clinical use. Future research should focus on refining delivery methods, exploring combination treatments, and clinical trials to ensure OVT's efficacy and safety for OS. Overall, OVT represents a novel approach with the potential to drastically improve survival outcomes for patients with OS.

Case report: Metastatic refractory undifferentiated small round-cell sarcoma successfully treated with surufatinib and camrelizumab

Background

Undifferentiated small round-cell sarcomas (uSRCSs) are a subgroup of sarcomas that are difficult to diagnose. Some uSRCSs have specific gene re-arrangements, but others do not. Currently, there is no specific treatments for advanced uSRCSs, and its treatment is largely based on general experience with sarcomas, which includes chemotherapy, targeted therapy, and immunotherapy. In this article, we report a patient with uSRCS who responded to treatment with anti-VEGF inhibitor surufatinib and anti-PD-1 inhibitor camrelizumab after progression on first-line chemotherapy, second-line anlotinib combined with immunotherapy, and third-line chemotherapy.

Case description

In July 2020, a 37-year-old female patient was diagnosed with advanced uSRCS. Results for the Ewing sarcoma RNA binding protein 1 and Wilms tumor suppressor (EWSR1/WT1) fusion gene were negative. The patient was also negative with BCOR (BCL6 co-repressor) and CIC (capicua transcriptional repressor) fusion gene. The next-generation sequencing results revealed point mutations on Phosphatidylinositol-4,5-Bisphosphate 3-Kinase Catalytic Subunit Beta (PIK3CB), Transcription Factor Binding To IGHM Enhancer 3 (TFE3), Mucin 16 (MUC16), and AXL (Axl, also called UFO, ARK, and Tyro7, is part of a family of receptor tyrosine kinases). The patient received 4 cycles of the Ifosfamide and epirubicin hydrochloride regimen, and her best objective response was stable disease. On November 3, 2020, a computed tomography (CT) scan revealed progressive disease (PD). Two cycles of camrelizumab (a programmed death-1 inhibitor) plus anlotinib (an anti- vascular endothelial growth factor drug) were administered, but PD was again observed. Thus, a regimen of gemcitabine plus docetaxel was adopted. Unfortunately, the disease progressed once again after two cycles of the treatment. On February 4, 2021, the patient began to receive targeted therapy with surufatinib combined with camrelizumab. A CT scan showed that the tumor achieved a partial response. As of April 2023, the patient had a progression-free survival time of 26 months.

Conclusions

Surufatinib in combination with camrelizumab could be effective in the treatment of advanced uSRCSs.

Release of Exosomal PD-L1 in Bone and Soft Tissue Sarcomas and Its Relationship to Radiotherapy

(1) Background: Exosomal PD-L1 has garnered attention owing to its role in instigating systemic immune suppression. The objective of this study is to elucidate whether bone and soft tissue sarcoma cells possess the capacity to secrete functionally active exosomal PD-L1 and whether radiotherapy (RT) induces the exosomal PD-L1 release. (2) Methods: Human osteosarcoma cell line 143B and human fibrosarcoma cell line HT1080 were utilized. Exosomes were isolated from the culture medium and blood via ultracentrifugation. The expression of PD-L1 on both tumor cells and exosomes was evaluated. The inhibitory effect on PBMC was employed to assess the activity of exosomal PD-L1. Post radiotherapy, changes in PD-L1 expression were compared. (3) Results: Exosomal PD-L1 was detected in the culture medium of tumor cells but was absent in the culture medium of PD-L1 knockout cells. Exosomal PD-L1 exhibited an inhibitory effect on PBMC activation. In tumor-bearing mice, human-derived exosomal PD-L1 was detected in the bloodstream. Following radiotherapy, tumor cells upregulated PD-L1, and human-derived exosomal PD-L1 were detected in the bloodstream. (4) Conclusions: Exosomal PD-L1 emanates from bone and soft tissue sarcoma cells and is disseminated into the circulatory system. The levels of PD-L1 in tumor cells and the release of exosomal PD-L1 were augmented after irradiation with RT.

Uterine Mesenchymal Tumors: Updates on Pathology, Molecular Landscape, and Therapeutics

Background: Mesenchymal uterine tumors are a diverse group of neoplasms with varying biological potential. Many of these neoplasms can have overlapping morphologic similarities, which, in some instances, render their diagnosis and categorization thorough histomorphologic examination inconclusive. In the last decade, an exponential amount of molecular data aiming to more accurately characterize and, consequently, treat these tumors have accumulated. Objective: The goal of this narrative review is to provide a pathologic review, a genetic update, and to know the new therapeutic avenues of primary uterine mesenchymal neoplasms.

Collagen modification remodels the sarcoma tumor microenvironment and promotes resistance to immune checkpoint inhibition

Molecular mechanisms underlying immune checkpoint inhibitor (ICI) response heterogeneity in solid tumors, including soft tissue sarcomas (STS), remain poorly understood. Herein, we demonstrate that the collagen-modifying enzyme, procollagen-lysine,2-oxoglutarate 5-dioxygenase 2 (Plod2), which is over-expressed in many tumors relative to normal tissues, promotes immune evasion in undifferentiated pleomorphic sarcoma (UPS), a relatively common and aggressive STS subtype. This finding is consistent with our earlier observation that Plod2 promotes tumor metastasis in UPS, and its enzymatic target, collagen type VI (ColVI), enhances CD8+ T cell dysfunction. We determined that genetic and pharmacologic inhibition of Plod2 with the pan-Plod transcriptional inhibitor minoxidil, reduces UPS growth in an immune competent syngeneic transplant system and enhances the efficacy of anti-Pd1 therapy. These findings suggest that PLOD2 is an actionable cancer target and its modulation could augment immunotherapy responses in patients with UPS, and potentially other sarcomas and carcinomas.

Long Duration Pembrolizumab for Metastatic Undifferentiated Pleomorphic Soft Tissue Sarcoma With Multimodality Therapy

Patients with undifferentiated pleomorphic sarcoma (UPS) of soft tissue have responsiveness to immunotherapy treatment. Since few patients with soft tissue sarcoma respond to immunotherapy, guidelines for its management are lacking. Specifically, the optimal duration of immunotherapy is unclear. This report is unique owing to the probable longest reporting of successful continuous immunotherapy for metastatic UPS over 6.5 years and 109 cycles. Here a patient who developed metastatic UPS is presented. The patient required systemic therapy for metastatic sarcoma, eventually with immunotherapy. A prolonged treatment over many years is elaborated. A robust response was seen but occasionally augmented by adding external beam radiation therapy (XRT). Treatment was tolerated without adverse effects. A brief review of current treatment practice and known risks of prolonged immunotherapy is presented. For similar patients, a lengthy treatment course, beyond that utilized for other malignancies, can be considered. This is likely to be safe if it is tolerated and without early adverse effects. Other treatment modalities such as palliative surgery and XRT are described which may also be required for management of mixed responses.

Modern Multidisciplinary Management of Soft Tissue Sarcoma of the Extremity and Trunk

Soft tissue sarcomas (STS) of the extremity and trunk are heterogeneous and rare tumors that require coordinated multidisciplinary management. Surgical resection remains the backbone of treatment for localized tumors, with the addition of radiotherapy to surgery to achieve high rates of local control. Despite this, overall survival is limited because of significant distant metastatic risk and a lack of efficacious systemic therapies. Clinical trials have produced conflicting results on the impact of systemic therapy in the neoadjuvant and adjuvant settings for patients with localized disease, leaving systemic treatment decisions largely guided by shared decision making and prognostic prediction tools such as nomograms. This article will review the foundational data as well as latest developments in surgical, radiotherapy, and systemic management supporting current practice guidelines for localized STS of the extremity and trunk.

Advancements in Diagnosis and Multimodal Treatment Strategies for Retroperitoneal Tumors: A Comprehensive Review

Retroperitoneal tumors (RPTs) encompass both benign and malignant entities, constituting ~0.1% to 0.2% of all malignant tumors, of which 70% to 80% manifest malignancy. Predominantly, retroperitoneal sarcomas (RPS) represent the most prevalent subtype among RPT. With over 70 histologic forms identified, liposarcomas and leiomyosarcomas emerge as the primary constituents of RPS. Accurate diagnosis of RPTs necessitates preoperative core-needle biopsy and comprehensive imaging assessment. The current staging protocol for RPS relies on the eighth edition of the American Joint Committee on Cancer/TNM classification. Surgical excision remains the established gold standard for treating RPS. Therapeutic approaches vary according to the underlying pathophysiology. Although chemotherapy and radiotherapy exhibit efficacy in managing metastatic and recurrent unresectable RPS, their role in primary RPS remains unresolved, necessitating further clinical trials for validation. Concurrently, ongoing research explores the potential of targeted therapies and immunotherapy. This literature review aims to provide a comprehensive overview of existing research, delineating diagnostic pathways and optimal therapeutic strategies for RPT.

Current Treatment Options: Uterine Sarcoma

OPINION STATEMENT

The cornerstone of treatment for uterine sarcoma, regardless of histologic type, remains en bloc surgical resection with total hysterectomy. In the case of incidental diagnosis during another procedure, such as myomectomy, where a hysterectomy was not performed initially, completion hysterectomy or cervical remnant removal is recommended. The completion of additional surgical procedures, including bilateral salpingo-oophorectomy and lymphadenectomy, remains nuanced. Bilateral salpingo-oophorectomy remains controversial in the setting of most subtypes of uterine sarcoma, except in the case of hormone-receptor positivity, such as in low grade endometrial stromal sarcoma, where it is indicated as part of definitive surgical treatment. In the absence of apparent nodal involvement, we do not recommend performing universal lymphadenectomy for patients with sarcoma. We recommend systemic therapy for patients with extra-uterine or advanced stage disease, high-grade histology, and recurrence. The most active chemotherapy regimens for advanced, high-grade disease remain doxorubicin or gemcitabine and docetaxol combination therapy. A notable exception is low grade endometrial stromal sarcoma, where we recommend anti-hormonal therapy in the front-line setting. Radiation therapy is reserved for selected cases where it can aid in palliating symptoms.

Emerging therapies in Ewing sarcoma

PURPOSE OF REVIEW

There is an unmet need to improve outcomes for patients for Ewing sarcoma, a rare, aggressive sarcoma with a peak incidence in adolescents and young adults (AYA). Current therapy at diagnosis involves multiagent chemotherapy and local therapy, but despite intensification of treatment, those with metastases at diagnosis and recurrent disease have poor outcomes.

RECENT FINDINGS

Improved understanding of Ewing sarcoma biology has identified novel targets with promising activity in Ewing sarcoma patients, including tyrosine kinase inhibitors that are now undergoing evaluation as combination and maintenance therapy. Other emerging therapies include those that target the EWSR1::FLI1 fusion oncoprotein, and act on DNA damage, cell cycle and apoptotic pathways. Immunotherapeutic approaches, particularly CAR-T-cell therapy directed at GD2, also hold promise. Recent collaborative clinical trials that have defined an international standard of care for patients with newly diagnosed Ewing sarcoma and novel platform studies with adaptive designs offer unique opportunities to investigate these therapies inclusive of all ages.

SUMMARY

Close international collaboration between clinicians and biologists will allow us to prioritize promising emerging therapies and develop biomarkers to facilitate their incorporation into standard of care and more rapidly translate into benefit for Ewing sarcoma patients.

A Detailed Examination of Retroperitoneal Undifferentiated Pleomorphic Sarcoma: A Case Report and Review of the Existing Literature

This detailed review focuses on retroperitoneal undifferentiated pleomorphic sarcoma (UPS), a particularly aggressive soft-tissue sarcoma that poses unique diagnostic and therapeutic challenges due to its rarity and complex presentation. By documenting a new case of retroperitoneal UPS and conducting a comprehensive review of all known cases, this article aims to expand the existing body of knowledge on the epidemiology, molecular pathogenesis, and treatment strategies associated with this rare disease. The complexity of diagnosing UPS is emphasized given that it rarely occurs in the retroperitoneal space and its histological and molecular complexity often complicates its recognition. This review highlights the need for specialized diagnostic approaches, including advanced imaging techniques and histopathological studies, to accurately diagnose and stage the disease. In terms of treatment, this paper advocates a multidisciplinary approach that combines surgery, radiotherapy and chemotherapy and tailors it to individual patients to optimize treatment outcomes. This review highlights case studies that illustrate the effectiveness of surgical intervention in the treatment of these tumors and emphasize the importance of achieving clear surgical margins to prevent recurrence. Furthermore, this review discusses the potential of new molecular targets and the need for innovative therapies that could bring new hope to patients affected by this challenging sarcoma.

Prognostic Role of OX40, LAG-3, TIM-3 and PD-L1 Expression in Bone and Soft Tissue Sarcomas

Introduction: The current study aims to evaluate the OX40, TIM-3, LAG-3, and PD-L1 targeted pathways in the regulation of T-cell activity in sarcoma patients to determine their relationship with overall survival (OS). Method: This study included one hundred and eleven patients with bone and soft tissue sarcoma diagnosed in two centers between 2010 and 2020. OX40, LAG-3, TIM-3 and PD-L1 expression levels were evaluated immunohistochemically from pathology preparations. Results: PD-L1 staining was detected in tumor cells, OX40, LAG-3, TIM-3 staining was detected in inflammatory cells in tumor tissue. In univariate analysis, no significant relationship was found between OX40, TIM-3, LAG-3, and PD-L1 staining and overall survival (respectively: p = 0.12, p = 0.49, p = 0.31, p = 0.95). When grade and stage at diagnosis, which were found to be significant in univariate analysis, along with OX-40, TIM-3, LAG-3, and PD-L1, were evaluated in multivariate analysis, a positive effect of OX-40 staining on overall survival was determined (p = 0.009). Considering the correlation between PDL-1 and OX40, TIM-3, and LAG-3 staining, a significant positive correlation was found between PDL-1 and TIM-3 and LAG-3 staining (respectively; p = 0.002, p = 0.001). Conclusions: There was no significant relationship between the PDL-1 staining percentage of tumor cells and OX40, TIM-3, and LAG-3 staining in inflammatory cells with the OS of sarcoma patients. However, detecting a significant positive correlation between PDL-1 staining and TIM-3 and LAG-3 staining also holds promise for finding effective targetable combination therapies that can prolong survival in sarcoma patients in the future.

DNA Mutational and Copy Number Variation Profiling of Primary Craniofacial Osteosarcomas by Next-Generation Sequencing

BACKGROUND

Craniofacial osteosarcomas (CFOS) are uncommon malignant neoplasms of the head and neck with different clinical presentation, biological behavior and prognosis from conventional osteosarcomas of long bones. Very limited genetic data have been published on CFOS.

METHODS

In the current study, we performed comprehensive genomic studies in 15 cases of high-grade CFOS by SNP array and targeted next generation sequencing.

RESULT

Our study shows high-grade CFOS demonstrate highly complex and heterogenous genomic alterations and harbor frequently mutated tumor suppressor genes TP53, CDKN2A/B, and PTEN, similar to conventional osteosarcomas. Potentially actionable gene amplifications involving CCNE1, AKT2, MET, NTRK1, PDGFRA, KDR, KIT, MAP3K14, FGFR1, and AURKA were seen in 43% of cases. GNAS hotspot activating mutations were also identified in a subset of CFOS cases, with one case representing malignant transformation from fibrous dysplasia, suggesting a role for GNAS mutation in the development of CFOS.

CONCLUSION

High-grade CFOS demonstrate highly complex and heterogenous genomic alterations, with amplification involving receptor tyrosine kinase genes, and frequent mutations involving tumor suppressor genes.

Enhancing radiotherapy response via intratumoral injection of a TLR9 agonist in autochthonous murine sarcomas

Radiation therapy (RT) is frequently used to treat cancers, including soft-tissue sarcomas. Prior studies established that the toll-like receptor 9 (TLR9) agonist cytosine-phosphate-guanine oligodeoxynucleotide (CpG) enhances the response to RT in transplanted tumors, but the mechanisms of this enhancement remain unclear. Here, we used CRISPR/Cas9 and the chemical carcinogen 3-methylcholanthrene (MCA) to generate autochthonous soft-tissue sarcomas with high tumor mutation burden. Treatment with a single fraction of 20 Gy RT and 2 doses of CpG significantly enhanced tumor response, which was abrogated by genetic or immunodepletion of CD8+ T cells. To characterize the immune response to CpG+RT, we performed bulk RNA-Seq, single-cell RNA-Seq, and mass cytometry. Sarcomas treated with 20 Gy and CpG demonstrated increased CD8 T cells expressing markers associated with activation and proliferation, such as Granzyme B, Ki-67, and IFN-γ. CpG+RT also upregulated antigen presentation pathways on myeloid cells. Furthermore, in sarcomas treated with CpG+RT, TCR clonality analysis suggests an increase in clonal T cell dominance. Collectively, these findings demonstrate that CpG+RT significantly delays tumor growth in a CD8 T cell-dependent manner. These results provide a strong rationale for clinical trials evaluating CpG or other TLR9 agonists with RT in patients with soft-tissue sarcoma.

Targeting of SUMOylation leads to cBAF complex stabilization and disruption of the SS18::SSX transcriptome in Synovial Sarcoma

Synovial Sarcoma (SS) is driven by the SS18::SSX fusion oncoprotein and is ultimately refractory to therapeutic approaches. SS18::SSX alters ATP-dependent chromatin remodeling BAF (mammalian SWI/SNF) complexes, leading to the degradation of canonical (cBAF) complex and amplified presence of an SS18::SSX-containing non-canonical BAF (ncBAF or GBAF) that drives an SS-specific transcription program and tumorigenesis. We demonstrate that SS18::SSX activates the SUMOylation program and SSs are sensitive to the small molecule SAE1/2 inhibitor, TAK-981. Mechanistically, TAK-981 de-SUMOylates the cBAF subunit SMARCE1, stabilizing and restoring cBAF on chromatin, shifting away from SS18::SSX-ncBAF-driven transcription, associated with DNA damage and cell death and resulting in tumor inhibition across both human and mouse SS tumor models. TAK-981 synergized with cytotoxic chemotherapy through increased DNA damage, leading to tumor regression. Targeting the SUMOylation pathway in SS restores cBAF complexes and blocks the SS18::SSX-ncBAF transcriptome, identifying a therapeutic vulnerability in SS, positioning the in-clinic TAK-981 to treat SS.

Emerging Treatments Targeting the Tumor Microenvironment for Advanced Chondrosarcoma

Chondrosarcoma (ChS), a malignant cartilage-producing tumor, is the second most frequently diagnosed osseous sarcoma after osteosarcoma. It represents a very heterogeneous group of malignant chemo- and radiation-resistant neoplasms, accounting for approximately 20% of all bone sarcomas. The majority of ChS patients have a good prognosis after a complete surgical resection, as these tumors grow slowly and rarely metastasize. Conversely, patients with inoperable disease, due to the tumor location, size, or metastases, represent a great clinical challenge. Despite several genetic and epigenetic alterations that have been described in distinct ChS subtypes, very few therapeutic options are currently available for ChS patients. Therefore, new prognostic factors for tumor progression as well as new treatment options have to be explored, especially for patients with unresectable or metastatic disease. Recent studies have shown that a correlation between immune infiltrate composition, tumor aggressiveness, and survival does exist in ChS patients. In addition, the intra-tumor microvessel density has been proven to be associated with aggressive clinical behavior and a high metastatic potential in ChS. This review will provide an insight into the ChS microenvironment, since immunotherapy and antiangiogenic agents are emerging as interesting therapeutic options for ChS patients.

Immunotherapy in Sarcoma: Current Data and Promising Strategies

Traditionally sarcomas have been considered immunologically quiet tumours, with low tumour mutational burden (TMB) and an immunosuppressive tumour microenvironment (TME), consisting of decreased T-cell infiltration and elevated levels of H1F1α, macrophages and neutrophils.1,2 However, research has shown that a subset of sarcomas are immunologically 'hot' with either high TMB, PDL-1 expression, CD8+ T cells or presence of tertiary lymphoid structures (TLS) demonstrating sensitivity to immunotherapy.3,4 Here, we review the current evidence for immunotherapy use in bone sarcomas (BS) and soft tissue sarcomas (STS), with immune checkpoint inhibitors (ICI) and adoptive cellular therapies including engineered T-cell therapies, chimeric antigen receptor (CAR) T-cell therapies, tumour infiltrating lymphocytes (TILs) and cancer vaccines and biomarkers of response.

FBXO22 is a potential therapeutic target for recurrent chondrosarcoma

Chondrosarcoma (CHS) is a malignant bone tumor with insensitivity to both radiotherapy and chemotherapy, and a high recurrence rate. However, the latent mechanism of recurrent CHS (Re-CHS) remains elusive. Here, we discovered that FBXO22 was highly expressed in clinical samples of Re-CHS. FBXO22 played a significant role in various cancers. However, the role of FBXO22 in Re-CHS remained unclear. Our research demonstrated that suppressing FBXO22 abated the proliferation and migration of CHS cells and facilitated their apoptosis. In addition, suppressing FBXO22 raised the expression of PD-L1 in Re-CHS. All these findings provide new evidence for using FBXO22 and PD-L1 as combined targets to prevent and treat Re-CHS, which may prove to be a novel strategy for immunotherapy of CHS, especially Re-CHS.

Fate control engagement augments NK cell responses in LV/hu-IL-12 transduced sarcoma

INTRODUCTION

NK cells are an untapped resource for cancer therapy. Sarcomas transduced with lentiviruses to express human IL-12 are only cleared in mice bearing mature human NK cells. However, systemic inflammation limits IL-12 utilization. Fate control a.k.a. "suicide mechanisms" regulate unchecked systemic inflammation caused by cellular immunotherapies. Despite increasing utilization, there remains limited data on immune consequences or tumor-directed effects of fate control.

OBJECTIVES

We sought to engage the mutant thymidylate kinase (mTMPK) metabolic fate control system to regulate systemic inflammation and assess the impact on NK cell effector functions.

METHODS

Primary human sarcoma short-passage samples and cell lines were transduced with LV/hu-IL-12_mTMPK engineering expression of IL-12 and an AZT-associated fate control enzyme. We assessed transduced sarcoma responses to AZT engagement and subsequent modulation of NK cell functions as measured by inflammatory cytokine production and cytotoxicity.

RESULTS

AZT administration to transduced (LV/hu-IL-12_mTMPK) short-passage primary human sarcomas and human Ewing sarcoma, osteosarcoma, and rhabdomyosarcoma cell lines, abrogated the robust expression of human IL-12. Fate control activation elicited a specific dose-dependent cytotoxic effect measured by metabolic activity (WST-1) and cell death (Incucyte). NK effector functions of IFN-γ and cytotoxic granule release were significantly augmented despite IL-12 abrogation. This correlated with preferentially induced expression of NK cell activation ligands.

CONCLUSIONS

mTMPK fate control engagement terminates transduced sarcoma IL-12 production and triggers cell death, but also augments an NK cell-mediated response coinciding with metabolic stress activating surface ligand induction. Fate control engagement could offer a novel immune activation method for NK cell-mediated cancer clearance.