Human Sarcoma Research Articles

A major role for Nrf2 transcription factors in cell transformation by KSHV encoded oncogenes.

Kaposi’s sarcoma (KS) is the most common tumor in AIDS patients. The highly vascularized patient’s skin lesions are composed of cells derived from the endothelial tissue transformed by the KSHV virus. Heme oxygenase-1 (HO-1) is an enzyme upregulated by the Kaposi´s sarcoma-associated herpesvirus (KSHV) and highly expressed in human Kaposi Sarcoma (KS) lesions. The oncogenic G protein-coupled receptor (KSHV-GPCR or vGPCR) is expressed by the viral genome in infected cells. It is involved in KS development, HO-1 expression, and vascular endothelial growth factor (VEGF) expression. vGPCR induces HO-1 expression and HO-1 dependent transformation through the Ga13 subunit of heterotrimeric G proteins and the small GTPase RhoA. We have found several lines of evidence supporting a role for Nrf2 transcription factors and family members in the vGPCR-Ga13-RhoA signaling pathway that converges on the HO-1 gene promoter. Our current information assigns a major role to ERK1/2MAPK pathways as intermediates in signaling from vGPCR to Nrf2, influencing Nrf2 translocation to the cell nucleus, Nrf2 transactivation activity, and consequently HO-1 expression. Experiments in nude mice show that the tumorigenic effect of vGPCR is dependent on Nrf2. In the context of a complete KSHV genome, we show that the lack of vGPCR increased cytoplasmic localization of Nrf2 correlated with a downregulation of HO-1 expression. Moreover, we also found an increase in phospho-Nrf2 nuclear localization in mouse KS-like KSHV (positive) tumors compared to KSHV (negative) mouse KS-like tumors. Our data highlights the fundamental role of Nrf2 linking vGPCR signaling to the HO-1 promoter, acting upon not only HO-1 gene expression regulation but also in the tumorigenesis induced by vGPCR. Overall, these data pinpoint this transcription factor or its associated proteins as putative pharmacological or therapeutic targets in KS.

Hyaluronan/Zinc Oxide Nanocomposite-Based Membrane: Preparation, Characterization, and In Vitro and In Vivo Evaluation

Hyaluronic acid (HA) has attracted the attention of scientists for its application in many medical fields owing to its intrinsic properties such as biodegradability, biocompatibility, and nontoxicity. Poor stability and antibacterial activity are the most significant drawbacks of using HA in preparing a wound dressing. The wound dressing should be able to swell and absorb exudates from the wound, as well as possess antibacterial activity. Herein, we successfully prepared an HA-based antibacterial wound dressing that can swell more than 500 times and with good mechanical properties. HA was used both as reducing and stabilizing agents, and zinc oxide nanoparticles (ZnO-NPs) were incorporated via in situ synthesis. The uniform spherical shape of ZnO-NPs (50 ± 10 nm) was synthesized and assembled on a hyaluronan/polyvinyl alcohol matrix (HA/PVA), forming stable and evenly distributed ZnO-NPs, which interacted with the HA/PVA. Such a hybrid nanostructure prevented ZnO-NPs from dropping off the PVA/HA network and thus minimized the toxicity of NPs. Concerning the slow release of NPs, the nanocomposite membrane still exhibited significant antibacterial activity against different types of bacteria (G+/−). The ZnO-NPs/HA/PVA composite membrane allows the attachment and growth of normal human dermal fibroblasts and human primary osteogenic sarcoma (Saos-2) without exhibiting toxicity. In vivo measurements showed that the nanocomposite PVA/HA/ZnO-NP membrane promoted infected wound healing compared with the control sample. The results obtained suggest that the investigated nanocomposite has reasonable potential as an antibacterial wound dressing material.

Abstract PR010: Development of a pre-clinical metastatic model of human sarcoma to identify therapeutic targets

Abstract Targeted therapies have led to significant advances in the treatment of multiple tumor types resulting in more effective and often, less toxic therapeutic options. In sarcomas, the development of targeted therapies has been met limited success. There are more than 70 sarcoma subtypes that vary in histology, clinical course and patient demographics. Despite these clear differences, clinically, sarcomas are treated similarly with variable efficacy. Patients with localized disease are treated with surgery, radiation, and often chemotherapy. Even with this aggressive multimodality treatment, 35% of patients will develop incurable metastatic disease. This highlights the need for additional therapies targeting micrometastatic disease or cells within the primary tumor with a high propensity for metastasis. Understanding the pathways driving the formation of sarcoma metastasis would allow for the development of new therapies. Targeted treatments are limited due to the heterogeneity of the disease and the paucity of pre-clinical models that accurately reflect the human disease. We have focused on creating in vivo models of sarcoma development and metastasis that can be used as the basis of further studies and to test potential therapeutic targets. Mesenchymal stem cells (MSCs) are the presumed cell of origin for sarcomas and therefore, the starting cell for our investigations. We hypothesized that by recreating key genetic events in human MSCs, we could generate sarcomas in vivo that are reflective of the human disease. RB1 and P53, tumor suppressors that are often mutated or functionally inactive in sarcomas were first targeted using CRISPR-Cas9 technology in MSCs that have been immortalized by human telomerase (hTERT). Genes that are overexpressed or amplified in The Cancer Genome Atlas (TCGA) data were identified and a library of potential oncogenes was generated. This library was then added to RB1-/-P53+/- cells through lentiviral transduction. Targeting of key tumor suppressors and adding oncogenic drivers resulted in the formation of high-grade human sarcomas subcutaneously. We then sought to investigate the ability of these cells to metastasize. Injection of cells intramuscularly (into the thigh) in immunocompromised mice resulted in the formation of spontaneous lung metastasis without clear evidence of disease in other organs. This pattern clinically reflects that of human disease. Comparing oncogenic genes from metastatic outgrowths to primary tumors identified KLF4, DDIT3, JUN, and KRAS as being enriched in metastatic cells. This system allows for reproducible and robust genetic manipulation of tumor cells to characterize key drivers of metastatic growth. This will result in the identification and validation of new therapeutic targets to treat or prevent metastatic disease in our patients. Citation Format: Janai R. Carr-Ascher. Development of a pre-clinical metastatic model of human sarcoma to identify therapeutic targets [abstract]. In: Proceedings of the AACR Special Conference: Sarcomas; 2022 May 9-12; Montreal, QC, Canada. Philadelphia (PA): AACR; Clin Cancer Res 2022;28(18_Suppl):Abstract nr PR010.

Abstract B018: A robust system to study human soft-tissue sarcoma lung metastasis

Abstract Soft-tissue sarcoma (STS) is a rare connective tissue cancer that encompasses over 50 distinct subtypes including liposarcoma, undifferentiated pleomorphic sarcoma (UPS) and pleomorphic rhabdomyosarcoma. While these subtypes are histologically and genetically different, all are capable of metastasizing into the lungs. However, the mechanisms of metastasis are poorly understood, and patients with metastatic disease have low survival rates. Current statistics show that these patients have a 15% 5-year relative survival rate. It is crucial to understand the mechanisms of metastasis to improve patient therapeutics and survival. Thus, we developed a robust system to enrich and study spontaneous metastatic cells in STS. To do this, we started by screening multiple cell lines for metastatic activity in-vivo. First, immunocompromised mice were injected in the thigh (intramuscularly) with tumor cells. The liposarcoma cell line SW872 gave rise to metastatic tumors in the lung although with limited penetrance and a long latency. Therefore, we identified a mouse with a high metastatic burden and generated a cell line from the primary tumor that was highly metastatic. These serially passaged cells were injected intramuscularly into the thigh of immunocompromised mice and allowed to spontaneously metastasize. This resulted in earlier detection of tumors, and a decreased latency to metastatic disease. For downstream analysis, we enriched the metastatic population resulting from the serially passaged tumor. This was accomplished by first digesting lungs, then depleting mouse cells with magnetic beads. We further enriched the population by sorting HLA-APC positive (human) cells using fluorescence-activated cell sorting (FACS). This process was necessary to reduce mouse cell contamination, and ensure we solely analyzed human cells. Afterwards, metastatic cells can be compared to the primary tumor using RNA, ATAC or Whole-Exome sequencing. We hypothesize that a comparison between the primary and metastatic tumors will identify pathways that allow cells to metastasize. These pathways can be targeted in future therapeutics to improve patient outcomes. This system can also be applied to other STS subtypes. Overall, our robust system allows us to study spontaneous lung metastases, is reflective of the human disease and will provide insight into the mechanisms of metastasis in STS. Citation Format: Maria Muñoz, Janai R. Carr-Ascher. A robust system to study human soft-tissue sarcoma lung metastasis [abstract]. In: Proceedings of the AACR Special Conference: Sarcomas; 2022 May 9-12; Montreal, QC, Canada. Philadelphia (PA): AACR; Clin Cancer Res 2022;28(18_Suppl):Abstract nr B018.

Abstract B005: Hypoxic sarcoma spheroid on a chip: Insights into treatment response

Abstract Context: Hypoxia is found in at least 47% of soft-tissue sarcoma (STS) patients and is known to be a major contributor to treatment resistance, metastasis progression and associated with poor prognosis. Indeed, expression of hypoxic proteins (HIF1-α, CAIX) in STS is associated with a shorter overall survival, and a shorter progression-free survival in patients. Specifically, Yang et al. demonstrated in 2017 that patients stratified by a 24-gene hypoxia signature had a poorer distant metastasis free survival. Nevertheless, hypoxia is seldom considered during treatment development due to the lack of a user-friendly way to culture naturally hypoxic 3D tumor models. Therefore, we developed a user-friendly in vitro preclinical tool allowing the study of natural chronic hypoxia and its effect on treatment response. Methods: Microfabrication technologies were used to design a microfluidic chip allowing culture, maintenance, treatment, and analysis of 240 STS naturally hypoxic spheroids (750µm of diameter). SK-LMS-1 Human leiomyosarcoma and STS117 (human primary undifferentiated pleomorphic sarcoma cells) spheroids were formed 48h after seeding. Gold-standard hypoxic protein Hypoxia Inducible Factor 1 alpha (HIF1- α) and Carbonic Anhydrase IX (CAIX) expression was assessed by Western Blot (WB). Spatial distribution of CAIX was assessed by immunofluorescence (IF). Based on the IF, an in silico model of the oxygen consumption of the spheroids was built using COMSOL. As a proof of concept, the spheroids were treated using two oxygen-dependent treatment: RT and hypoxia prodrug Tirapazamine (TPZ). DNA-damages were quantified using yH2AX in IF to assess treatment efficacy. Results: These spheroids on-a-chip are the largest to date (>750µm), and express gold-standard hypoxic protein CAIX in their core only, a feature absent in spheroids of 450µm of diameter of the same cell lines. HIF1-α expression patterns were cell line dependent. CAIX expression in SK-LMS-1 and STS117 large spheroids was respectively 7.8 and 24 times higher than in 450µm spheroids. Quantification of DNA damages (count of yH2AX foci/nuclei area in mm²) demonstrated that TPZ preferentially targets the hypoxic core. However, the response (DNA damages) to RT alone showed no evidence of radioresistance of the hypoxic regions, on samples fixed 24h after irradiation. A possible explanation could be that, in 24h, the oxygen-dependent DNA repair and the accumulation of DNA damages in hypoxic regions hide the oxygen-dependent radioresistance. Therefore, quantification of DNA damages with yH2AX 30min after irradiation is currently being investigated, as maximum DNA damage response has been shown to be observed at this time point. Our 750µm spheroids naturally display a hypoxic core expressing gold-standard hypoxic protein CAIX at 120µm of depth, a feature absent in smaller spheroids. Together, these results cement our microfluidic device and our spheroids as a potent fundamental and pre-clinical tool to explore the biology of hypoxia on 3D tumor model, its effects on treatment response. Citation Format: Elena Refet-Mollof, Ouafa Najyb, Rodin Chermat, Audrey Glory, Julie Lafontaine, Philip Wong, Thomas Gervais. Hypoxic sarcoma spheroid on a chip: Insights into treatment response [abstract]. In: Proceedings of the AACR Special Conference: Sarcomas; 2022 May 9-12; Montreal, QC, Canada. Philadelphia (PA): AACR; Clin Cancer Res 2022;28(18_Suppl):Abstract nr B005.

Abstract A017: Multiple intratumoral sources of kit ligand promote oncogenic kit signaling in gastrointestinal stomal tumor

Abstract Introduction: Gastrointestinal stromal tumor (GIST) is the most common human sarcoma and is typically driven by a single mutation in the Kit receptor. While highly effective, tyrosine kinase inhibitors like imatinib are not curative. The natural ligand for the Kit receptor is Kit Ligand (KitL), which exists in both soluble and membrane-bound forms. We sought to determine the role of KitL in the oncogenic Kit signaling of GIST. Methods: KitV558Δ/+ mice, which spontaneously develop an intestinal GIST, were treated with imatinib or vehicle for 1 week, and sorted non-immune (CD45-) cells from tumors were submitted for single-cell RNA sequencing (n=3/group). GIST T1 cells were treated with KitL with or without imatinib and oncogenic Kit signaling was evaluated. KitV558Δ/+ mice were crossed with various KitL mutant and inducible models and tumor weights were measured (n=3-4/group). Human GISTs were stained for KitL expression by IHC, and an existing bulk RNA sequencing human GIST dataset with matched human serum was analyzed. Results: Unsupervised clustering revealed endothelial, smooth muscle, and tumor cells had high expression of KitL RNA in untreated tumors from KitV558Δ/+ mice. Imatinib therapy increased KitL RNA in all 3 cell types, suggesting that extra-tumoral KitL expression is dependent on oncogenic signaling (p<0.05). In GIST T1 cells, exogenous KitL increased Kit activation and reduced imatinib’s efficacy. Tumors from mice with homozygous KitL deletion (KitV558Δ/+;Etv1Cre-ERT2/+;KitLflox/flox) were smaller than tumors from littermates with heterozygous KitL deletion (KitV558Δ /+;Etv1Cre-ERT2/+;KitLflox/+), providing evidence that KitL contributes to GIST development in vivo despite the presence of mutated Kit (p<0.05). Furthermore, tumors from KitV558Δ/+;KitLKitL1Δ/KitL1Δ mice, which lack the proteolytic cleavage site for soluble KitL, were smaller than matched KitV558Δ/+ mice, indicating that soluble KitL is important for maximal tumor growth in vivo (p<0.05). Heterogeneous KitL expression was confirmed in human GISTs by IHC. Human serum contained more KitL in patients with tumors resistant to imatinib and in those with tumors expressing more KitL RNA(p<0.05). Conclusions: KitL is produced by multiple cell types within GIST and contributes to oncogenesis. Targeting KitL may be important for optimal tumor therapy. Citation Format: Andrew D. Tieniber, Ferdinando Rossi, Andrew Hanna, Mengyuan Liu, Mark Etherington, Kevin Do, Laura Wang, Ronald P. DeMatteo. Multiple intratumoral sources of kit ligand promote oncogenic kit signaling in gastrointestinal stomal tumor [abstract]. In: Proceedings of the AACR Special Conference: Sarcomas; 2022 May 9-12; Montreal, QC, Canada. Philadelphia (PA): AACR; Clin Cancer Res 2022;28(18_Suppl):Abstract nr A017.

P53 Pathway Inactivation Drives SMARCB1-deficient p53-wildtype Epithelioid Sarcoma Onset Indicating Therapeutic Vulnerability Through MDM2 Inhibition.

Loss of the gene SMARCB1 drives the development of malignant rhabdoid tumors, epithelioid sarcomas, and other malignancies. The SMARCB1 protein is a core component of the SWI/SNF (SWItch/Sucrose Non-Fermentable) family of chromatin remodeling complexes, which are important regulators of gene expression and cell differentiation. Here, we use CRISPR-Cas9 to create germline smarcb1 loss of function in zebrafish. We demonstrate that the combination of smarcb1 deficiency with mutant p53 results in the development of epithelioid sarcomas, angiosarcomas, and carcinomas of the thyroid and colon. Although human epithelioid sarcomas do not frequently harbor p53 mutations, smarcb1-deficient tumors in zebrafish were only observed following disruption of p53, indicating that p53 signaling in human tumors might be attenuated through alternative mechanisms, such as MDM2-mediated proteasomal degradation of p53. To leverage this possibility for the treatment of human epithelioid sarcoma, we tested small molecule-mediated disruption of the p53-MDM2 interaction, which stabilized p53 protein leading to p53-pathway reactivation, cell-cycle arrest, and increased apoptosis. Moreover, we found that MDM2 inhibition and the topoisomerase II inhibitor doxorubicin synergize in targeting epithelioid sarcoma cell viability. This could be especially relevant for patients with epithelioid sarcoma because doxorubicin represents the current gold standard for their clinical treatment. Our results therefore warrant reactivating p53 protein in SMARCB1-deficient, p53-wildtype epithelioid sarcomas using combined doxorubicin and MDM2 inhibitor therapy.

A novel anti-CD47-targeted blockade promotes immune activation in human soft tissue sarcoma but does not potentiate anti-PD-1 blockade.

The treatment options for metastatic soft tissue sarcomas (STSs) are limited. In most cases, immunotherapy with immune checkpoint inhibitors has not been successful so far. Macrophages dominate the immune landscape of STSs; thus, combinatorial strategies aiming at both tumor-infiltrating lymphocytes and macrophages may represent a particularly relevant treatment approach for metastatic or recurrent STSs. In this cohort study, 66 patients who underwent surgery for STSs were enrolled. Tumor cells and tumor-infiltrating immune cells were analyzed using flow cytometry and immunohistochemistry. In cell suspensions obtained from surgical resections, human T cells were activated by superparamagnetic polymer beads and cultured at a concentration of 0.3 × 106/µl in the absence or presence of therapeutic monoclonal antibodies (anti-PD-1, anti-CD47, and anti-PD-1 + anti-CD47). Supernatants from cell suspensions were analyzed using multiplex Luminex cytokine bead-based immunoassays. The most profound response to anti-CD47 therapy was observed in an undifferentiated pleiomorphic sarcoma which also displayed high expression of CD47 in the tumor microenvironment. Both anti-PD-1 and anti-CD47 therapies drastically increased the production of pro-inflammatory cytokines in the tumor microenvironment of STSs, but co-administration of both agents did not further increase cytokine secretion. Furthermore, all patient samples treated with a combination of both anti-PD-1 and anti-CD47 antibodies showed a dramatic reduction in cytokine secretion. Our findings suggest that anti-PD-1 and anti-CD47 therapies do not enhance each other, and the combined application of anti-PD-1 and anti-CD47 agents in vitro limits rather than potentiates their efficacy.

Characterisation of a Novel Cell Line (ICR-SS-1) Established from a Patient-Derived Xenograft of Synovial Sarcoma.

Synovial sarcoma is a rare translocation-driven cancer with poor survival outcomes, particularly in the advanced setting. Previous synovial sarcoma preclinical studies have relied on a small panel of cell lines which suffer from the limitation of genomic and phenotypic drift as a result of being grown in culture for decades. Patient-derived xenografts (PDX) are a valuable tool for preclinical research as they retain many histopathological features of their originating human tumour; however, this approach is expensive, slow, and resource intensive, which hinders their utility in large-scale functional genomic and drug screens. To address some of these limitations, in this study, we have established and characterised a novel synovial sarcoma cell line, ICR-SS-1, which is derived from a PDX model and is amenable to high-throughput drug screens. We show that ICR-SS-1 grows readily in culture, retains the pathognomonic SS18::SSX1 fusion gene, and recapitulates the molecular features of human synovial sarcoma tumours as shown by proteomic profiling. Comparative analysis of drug response profiles with two other established synovial sarcoma cell lines (SYO-1 and HS-SY-II) finds that ICR-SS-1 harbours intrinsic resistance to doxorubicin and is sensitive to targeted inhibition of several oncogenic pathways including the PI3K-mTOR pathway. Collectively, our studies show that the ICR-SS-1 cell line model may be a valuable preclinical tool for studying the biology of anthracycline-resistant synovial sarcoma and identifying new salvage therapies following failure of doxorubicin.

Ubiquitin-specific protease TRE17/USP6 promotes tumor cell invasion through the regulation of glycoprotein CD147 intracellular trafficking

Disordered expression and distribution of plasma membrane proteins at the cell surface leads to diverse malignant phenotypes in tumors, including cell invasion. The ubiquitin-specific protease TRE17/USP6, an oncogene identified in Ewing sarcoma, is highly expressed in several cancers and locally aggressive tumor-like lesions. We have previously demonstrated that TRE17 regulates the trafficking of plasma membrane proteins that enter cells via clathrin-independent endocytosis (CIE); TRE17 prevents CIE cargo proteins from being targeted to lysosomes for degradation by deubiquitylating them. However, functional insights into the effects of TRE17-mediated CIE cargo trafficking on cell invasion remain unknown. Here, we show that increased expression of TRE17 enhances invasiveness of the human sarcoma cell line HT-1080 by elevating the cell surface levels of the membrane glycoprotein CD147, which plays a central role in tumor progression. We demonstrate overexpression of TRE17 decreases ubiquitylated CD147, which is accompanied by suppression of CD147 transport to lysosomes, resulting in the stabilization and increase of cell surface-localized CD147. On the other hand, we show knockdown of TRE17 decreases cell surface CD147, which is coupled with reduced production of matrix metalloproteinases, the enzymes responsible for extracellular matrix degradation. Furthermore, we demonstrate that inhibition of CD147 by a specific inhibitor alleviated the TRE17-promoted tumor cell invasion. We therefore propose a model for the pathogenesis of TRE17-driven tumors in which TRE17 increases CD147 at the cell surface by preventing its lysosomal degradation, which in turn enhances matrix metalloproteinase synthesis and matrix degradation, thereby promoting tumor cell invasion.

Combined analysis of expression, prognosis and immune infiltration of GINS family genes in human sarcoma.

Objective: This study was undertaken to explore the expression and prognostic value of GINS family in human sarcoma, as well as the association between the expression levels of the GINS family and sarcoma immune infiltration.Results: We discovered that the mRNA expression levels of GINS1, GINS2, GINS3, and GINS4 were all higher in the majority of tumor tissues than in normal samples, of course, including sarcoma. Through the CCLE, all the four members expression were observed in high levels in sarcoma cell lines. In Gene Expression Profiling Analysis (GEPIA) and Kaplan-Meier Plotter, our results indicated that the poor overall survival (OS), disease-free survival (DFS) and relapse free survival (RFS) were tightly associated with the increased expression of GINS genes. In TIMER database, we found that highly expressed GINS was significantly correlated with the low infiltration level of CD4+ T cell and macrophage.Conclusions: The four GINS family members were all the prognostic biomarkers for the prognosis of human sarcoma and can reduce the level of immune cell infiltration in the sarcoma microenvironment.Methods: In terms of the expression levels of mRNA for GINS family members, a particular contrast in various cancers, especially human sarcoma, was conducted through ONCOMINE and GEPIA and CCLE databases. Kaplan-Meier Plotter was used to identify the prognostic value of GINS family in sarcoma. The relationship between the expression level of GINS and the infiltration of immune cells was analyzed in TIMER database.

A case report on large retroperitoneal liposarcoma

Even though rare, retroperitoneal masses evoke interest for so many reasons. They involve a wide variety of tumor types, both malignant and benign, making the diagnosis a challenge. Many tumor types have different clinical behaviors and treatments. Surgical resection is always challenging technically with no fixed steps of resection. The <1% of neoplasms are soft tissue sarcomas in humans. Liposarcoma is the most common retroperitoneal sarcoma among the retroperitoneal malignant tumors. More often than not, patients report late to the hospital due to the very slow growth and the onset of a few late symptoms, patients usually present at a late stage to the health care. Therefore, in most cases, the tumor is known to have reached enormous sizes and might have infiltrated vital structures. Here, we reported a case of large retroperitoneal liposarcoma weighing more than 8 kgs.

Ferula communis L. (Apiaceae) Root Acetone-Water Extract: Phytochemical Analysis, Cytotoxicity and In Vitro Evaluation of Estrogenic Properties.

Ferula communis L. (F. communis) belongs to the Apiaceae family and is a herbaceous plant with various pharmaceutical properties, due to the different contents of bioactive compounds extracted mainly from its roots, as well as its leaves and rhizome. To date, this plant extract has demonstrated estrogenic, anti-inflammatory, antiproliferative, cytotoxic, antimicrobial and anti-neoplastic properties. Its estrogenic activity is justified by the presence of ferutinin, an ester of a sesquiterpenic alcohol that acts as an agonist for estrogen receptors, with a chemical formula equal to C22H3O4. The component present in F. communis responsible for the toxicity of the plant is ferulenol, a prenylated coumarin with the chemical formula C24H30O3. This compound is capable of inducing mortality via its strong anti-coagulant properties, leading to a lethal hemorrhagic syndrome, ferulosis, in animals that feed on a chemotype of F. communis containing a high amount of ferulenol. The removal of the component ferulenol makes extracts of Ferula non-toxic. In fact, the remaining prenylated coumarins are not present in concentrations sufficient to induce toxicity. The intake of high concentrations of the extract of this plant leads a double dose-dependent effect that is typical of sesquiterpenes such as ferutinin. Here, we assessed the cytotoxicity and the estrogenic properties of the F. communis phytocomplex obtained through extraction using a mixture of acetone and water. Among the active constituents of F. communis, the identification of ferutinin and ferulenol was performed using HPLC. The effects of the extract were evaluated, following the removal of ferulenol, on three cell lines: human breast cancer MCF-7, human cervical cancer HeLa and human osteoblastic sarcoma Saos-2. The choice of these cell lines was justified by the need to mimic certain processes which may occur in vivo and which are estrogen-dependent. The obtained results demonstrated that F. communis extract, in addition to possessing an estrogenic-like property, showed a dose-dependent effect. Low concentrations (0.1–0.8 μM) demonstrated a hyperproliferative effect, whereas higher concentrations (1.6–50 μM) were toxic. Therefore, this extract could be an excellent candidate to make up for a reduction or lack of estrogen.

ERK5 Is a Major Determinant of Chemical Sarcomagenesis: Implications in Human Pathology.

Simple SummarySarcoma is a heterogeneous group of tumors poorly studied with few therapeutic opportunities. Interestingly, the role of MAPKs still remains unclear in sarcomatous pathology. Here, we describe for the first time the critical role of ERK5 in the biology of soft tissue sarcoma by using in vitro and in vivo approaches in a murine experimental model of chemical sarcomagenesis. Indeed, our observations were extrapolated to a short series of human leiomyosarcoma and rhabdomyosarcomas. Furthermore, transcriptome analysis allows us to demonstrate the critical role of KLF2 in the biological effects of ERK5. Therefore, the data presented here open new windows in the diagnosis and therapy of soft tissue sarcomas.Sarcomas are a heterogeneous group of tumors in which the role of ERK5 is poorly studied. To clarify the role of this MAPK in sarcomatous pathology, we used a murine 3-methyl-cholanthrene (3MC)-induced sarcoma model. Our data show that 3MC induces pleomorphic sarcomas with muscle differentiation, showing an increased expression of ERK5. Indeed, this upregulation was also observed in human sarcomas of muscular origin, such as leiomyosarcoma or rhabdomyosarcoma. Moreover, in cell lines derived from these 3MC-induced tumors, abrogation of Mapk7 expression by using specific shRNAs decreased in vitro growth and colony-forming capacity and led to a marked loss of tumor growth in vivo. In fact, transcriptomic profiling in ERK5 abrogated cell lines by RNAseq showed a deregulated gene expression pattern for key biological processes such as angiogenesis, migration, motility, etc., correlating with a better prognostic in human pathology. Finally, among the various differentially expressed genes, Klf2 is a key mediator of the biological effects of ERK5 as indicated by its specific interference, demonstrating that the ERK5–KLF2 axis is an important determinant of sarcoma biology that should be further studied in human pathology.

Different effects of magnetic field on drug activity in human uterine sarcoma cell lines MES-SA and MES-SA/Dx5

ABSTRACT Previous studies reported that combined effect of magnetic field (MF) on cytotoxic drugs in human cancer cells. We focused on the effects of 60 Hz MF on drug activity in human uterine sarcoma MES-SA and drug-resistant variant MES-SA/Dx5 cells that overexpressed the membrane protein MDR1(P-glycoprotein), a drug efflux transporter for doxorubicin, daunorubicin, and etoposide, but not cisplatin. The cisplatin with MF caused 60% decrease in cell viability when compared with no MF treatment, cisplatin alone in MES-SA cells. Even in MES-SA/Dx5 cells, MF exposure equally enhanced cisplatin activity. Then, MF enhanced doxorubicin and daunorubicin activity in MES-SA cells and caused 60% decrease in the cell viability compared with these drugs only but had less effect on these drugs in MES-SA/Dx5 cells. Etoposide activity was unaffected by MF exposure in both cell lines, although etoposide is a MDR1 substrate as with doxorubicin and daunorubicin. Thus, MF had no direct impact on MDR1 in the cell membrane. However, the differences in doxorubicin and daunorubicin activity between MES-SA and MES-SA/Dx5 data revealed that the presence of MDR1 in abundance prevented the enhancing effects of MF on doxorubicin and daunorubicin activity. These results suggested that MF may act in the opposite direction of MDR1, affect the drug influx transporters for doxorubicin and daunorubicin, and facilitate anticancer drug uptake into the cells.

Alternative splicing of Apoptosis Stimulating Protein of TP53-2 (ASPP2) results in an oncogenic isoform promoting migration and therapy resistance in soft tissue sarcoma (STS)

BackgroundMetastatic soft tissue sarcoma (STS) are a heterogeneous group of malignancies which are not curable with chemotherapy alone. Therefore, understanding the molecular mechanisms of sarcomagenesis and therapy resistance remains a critical clinical need. ASPP2 is a tumor suppressor, that functions through both p53-dependent and p53-independent mechanisms. We recently described a dominant-negative ASPP2 isoform (ASPP2κ), that is overexpressed in human leukemias to promote therapy resistance. However, ASPP2κ has never been studied in STS. Materials and methodsExpression of ASPP2κ was quantified in human rhabdomyosarcoma tumors using immunohistochemistry and qRT-PCR from formalin-fixed paraffin-embedded (FFPE) and snap-frozen tissue. To study the functional role of ASPP2κ in rhabdomyosarcoma, isogenic cell lines were generated by lentiviral transduction with short RNA hairpins to silence ASPP2κ expression. These engineered cell lines were used to assess the consequences of ASPP2κ silencing on cellular proliferation, migration and sensitivity to damage-induced apoptosis. Statistical analyses were performed using Student’s t-test and 2-way ANOVA.ResultsWe found elevated ASPP2κ mRNA in different soft tissue sarcoma cell lines, representing five different sarcoma sub-entities. We found that ASSP2κ mRNA expression levels were induced in these cell lines by cell-stress. Importantly, we found that the median ASPP2κ expression level was higher in human rhabdomyosarcoma in comparison to a pool of tumor-free tissue. Moreover, ASPP2κ levels were elevated in patient tumor samples versus adjacent tumor-free tissue within individual patients. Using isogenic cell line models with silenced ASPP2κ expression, we found that suppression of ASPP2κ enhanced chemotherapy-induced apoptosis and attenuated cellular proliferation.ConclusionDetection of oncogenic ASPP2κ in human sarcoma provides new insights into sarcoma tumor biology. Our data supports the notion that ASPP2κ promotes sarcomagenesis and resistance to therapy. These observations provide the rationale for further evaluation of ASPP2κ as an oncogenic driver as well as a prognostic tool and potential therapeutic target in STS.

Abstract 6007: Identification of drivers of soft tissue sarcoma metastasis

Abstract Soft tissue sarcomas are a rare and heterogeneous group of tumors with a 65% five-year survival rate despite aggressive treatment with surgery, radiation, and chemotherapy. Even with intensive multimodality treatment, many patients will develop incurable metastatic disease, providing evidence that our current therapies are ineffective and new treatments are desperately needed. Pre-clinical models to study metastasis of human soft tissue sarcomas are limited. We have developed a system that allows for the formation of distinct soft tissue sarcoma subtypes from mesenchymal stem cells that have been depleted of p53 and Rb1 using CRISPR. Injection of these cells intramuscularly results in metastasis to the lung. Using this novel model system, we have performed a genetic screen to identify pathways and specific drivers of sarcoma metastasis. This pre-clinical in vivo model system will allow for the identification of putative therapeutic targets to prevent the development of lethal metastatic growth. Citation Format: Janai R. Carr-Ascher, Maria Munoz. Identification of drivers of soft tissue sarcoma metastasis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 6007.

Abstract 3424: Deep mechanistic profiling of immune oncology (I-O) drug combinations in cancer patients with CIVO® intratumoral microdosing and NanoString GeoMx DSP

Abstract Despite over four thousand clinical trials investigating combinations of various anti-cancer agents with immune checkpoint inhibitors (CPI), few have demonstrated significant clinical improvement over CPI alone. This indicates a need for approaches that can guide development of complex (≥ 3 drug) I-O combination treatments by enabling far greater mechanistic understanding of response to drug exposure by components of the authentic tumor microenvironment (TME). Here we show how an approach based on two technologies, the Presage Comparative In Vivo Oncology (CIVO) Platform and the NanoString GeoMx Digital Spatial Profiler (GeoMx DSP), highlights drug synergies as well as mechanisms of resistance to drug exposure in the native and intact TME of cancer patients, providing a path to rapid identification of effective drug combinations. The CIVO platform enables trackable multiplexed intratumoral delivery of microdosed drugs, either as single agents or in combinations, allowing evaluation of the localized tumor response to drug candidates in the TME while capturing tumor heterogeneity and patient diversity. GeoMx DSP is a method for high-plex spatial profiling of mRNAs with rare-cell sensitivity. Combining these technologies in Phase 0 clinical studies in human soft tissue sarcoma patients we evaluated distinct tumor sites microdosed with either nivolumab (anti-PD1), aldesleukin (recombinant IL-2), the combination of nivolumab and aldesleukin, vehicle (no drug), or chemotherapy controls. Using the Nanostring Cancer Transcriptome Atlas we evaluated the effect of drug exposure on expression of over 1,800 genes simultaneously with spatial resolution across individual patient tumors. Synergistic elevation of multiple transcripts was observed at tumor sites exposed to the combination of aldesleukin and nivolumab. This included T-cell specific elevation of granzyme B, a classic biomarker of T-cell activation. Importantly, we show how events such as T-cell activation may be dampened by feedback loops involving immune suppressive responses including, but not limited to, elevation of IDO-1 in non-T-cell components of the TME. Results were observed across multiple patient tumors and were verified by conventional immuno-histochemistry or in situ hybridization. Performing these studies across different patients allows us to explore the inter-individual variation in drug responses. We believe this is an efficient and biologically relevant approach to better understanding feedback loops activated within the authentic TME and ultimately prioritizing drug combinations for clinical development. Citation Format: Jason P. Frazier, Kenneth R. Gundle, Marc Grenley, Gloria Kung, Kimberly Sottero, Kirsten Anderson, Richard Klinghoffer, Jonathan M. Derry. Deep mechanistic profiling of immune oncology (I-O) drug combinations in cancer patients with CIVO® intratumoral microdosing and NanoString GeoMx DSP [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 3424.

Clinical genomic profiling in the management of patients with soft tissue and bone sarcoma

There are more than 70 distinct sarcomas, and this diversity complicates the development of precision-based therapeutics for these cancers. Prospective comprehensive genomic profiling could overcome this challenge by providing insight into sarcomas’ molecular drivers. Through targeted panel sequencing of 7494 sarcomas representing 44 histologies, we identify highly recurrent and type-specific alterations that aid in diagnosis and treatment decisions. Sequencing could lead to refinement or reassignment of 10.5% of diagnoses. Nearly one-third of patients (31.7%) harbor potentially actionable alterations, including a significant proportion (2.6%) with kinase gene rearrangements; 3.9% have a tumor mutational burden ≥10 mut/Mb. We describe low frequencies of microsatellite instability (<0.3%) and a high degree of genome-wide loss of heterozygosity (15%) across sarcomas, which are not readily explained by homologous recombination deficiency (observed in 2.5% of cases). In a clinically annotated subset of 118 patients, we validate actionable genetic events as therapeutic targets. Collectively, our findings reveal the genetic landscape of human sarcomas, which may inform future development of therapeutics and improve clinical outcomes for patients with these rare cancers.

Prognostic value of p16, p53, and pcna in sarcoma and an evaluation of immune infiltration

Backgroundp16, p53, and proliferating cell nuclear antigen (pcna) genes play significant roles in many chromatin modifications and have been found to be highly expressed in a variety of tumor tissues. Therefore, they have been used as target genes for some tumor therapies. However, the differential expressions of the p16, p53, and pcna genes in human sarcomas and their effects on prognosis have not been widely reported.MethodsThe Oncomine dataset was used to analyze the transcription levels of p16, p53, and pcna genes, and the gene expression profile interactive analysis (GEPIA) dataset was used to analyze the differential expressions of p16, p53, and pcna. The expression levels of p16, p53, and pcna were further analyzed by Western Blotting. GEPIA and Kaplan–Meier analyses were used to analyze the prognostic value of p16, p53, and pcna. Furthermore, p16, p53, and pcna gene mutations and their association with overall survival (OS) and disease-free survival (DFS) were analyzed using cBioPortal datasets. In addition, genes co-expressed with p16, p53, and pcna were analyzed using Oncomine. The DAVID dataset was used to analyze the functional enrichment of p16, p53, pcna, and their co-expressed genes by Gene Ontology (GO) and Metascape were used to construct a network map. Finally, the immune cell infiltration of p16, p53, and pcna in patients with sarcoma was reported by Tumor Immune Estimation Resource (TIMER).Resultsp16, p53, and pcna were up-regulated in human sarcoma tissues and almost all sarcoma cell lines. Western Blotting showed that the expression of p16, p53, and pcna was elevated in osteosarcoma cell lines. The expression of pcna was correlated with OS, the expression of p16, p53, and pcna was correlated with relapse-free survival, and the genetic mutation of p16 was negatively correlated with OS and DFS. We also found that p16, p53, and pcna genes were positively/negatively correlated with immune cell infiltration in sarcoma.ConclusionsThe results of this study showed that p16, p53, and pcna can significantly affect the survival and immune status of sarcoma patients. Therefore, p16, p53, and pcna could be used as potential biomarkers of prognosis and immune infiltration in human sarcoma and provide a possible therapeutic target for sarcoma.