Molecular prognosticators of complex karyotype soft tissue sarcoma outcome: a tissue microarray-based study

Improving Immunotherapy Efficacy in Soft-Tissue Sarcomas: A Biomarker Driven and Histotype Tailored Review

Anti-PD-(L)1 therapies yield a disappointing response rate of 15% across soft-tissue sarcomas, even if some subtypes benefit more than others. The proportions of TAMs and TILs in their tumor microenvironment are variable, and this heterogeneity correlates to histotype. Tumors with a richer CD8+ T cell, M1 macrophage, and CD20+ cells infiltrate have a better prognosis than those infiltrated by M0/M2 macrophages and a high immune checkpoint protein expression. PD-L1 and CD8+ infiltrate seem correlated to response to immune checkpoint inhibitors (ICI), but tertiary lymphoid structures have the best predictive value and have been validated prospectively. Trials for combination therapies are ongoing and focus on the association of ICI with chemotherapy, achieving encouraging results especially with pembrolizumab and doxorubicin at an early stage, or ICI with antiangiogenics. A synergy with oncolytic viruses is seen and intratumoral talimogene laherpavec yields an impressive 35% ORR when associated to pembrolizumab. Adoptive cellular therapies are also of great interest in tumors with a high expression of cancer-testis antigens (CTA), such as synovial sarcomas or myxoid round cell liposarcomas with an ORR ranging from 20 to 50%. It seems crucial to adapt the design of clinical trials to histology. Leiomyosarcomas are characterized by complex genomics but are poorly infiltrated by immune cells and do not benefit from ICI. They should be tested with PIK3CA/AKT inhibition, IDO blockade, or treatments aiming at increasing antigenicity (radiotherapy, PARP inhibitors). DDLPS are more infiltrated and have higher PD-L1 expression, but responses to ICI remain variable across clinical studies. Combinations with MDM2 antagonists or CDK4/6 inhibitors may improve responses for DDLPS. UPS harbor the highest copy number alterations (CNA) and mutation rates, with a rich immune infiltrate containing TLS. They have a promising 15-40% ORR to ICI. Trials for ICB should focus on immune-high UPS. Association of ICI with FGFR inhibitors warrants further exploration in the immune-low group of UPS. Finally translocation-related sarcomas are heterogeneous, and although synovial sarcomas a poorly infiltrated and have a poor response rate to ICI, ASPS largely benefit from ICB monotherapy or its association with antiangiogenics agents. Targeting specific neoantigens through vaccine or adoptive cellular therapies is probably the most promising approach in synovial sarcomas.

Prognostic value of pretreatment anemia in patients with soft tissue sarcoma: A meta-analysis

BACKGROUND

Anemia is one of the most common manifestations in patients with cancer. Recently, multiple studies have shown a positive correlation between pretreatment anemia and tumor prognosis. Yet, the relationship between pretreatment anemia and the prognosis of soft tissue sarcomas (STS) is unclear.

METHODS

We searched the PubMed and EMBASE databases to identify relevant studies. Eligible studies were included according to the inclusion criteria to assess the relationship between pretreatment anemia and the prognosis of patients with STS. Prognostic significance was determined by studying hazard ratios (HR) and 95% confidence intervals (CIs).

RESULTS

A total of 12 studies are included. If there is significant heterogeneity, a random-effects model is used. Pooled data indicated that pretreatment anemia is related to poor overall survival (HR = 2.13; 95%CI = 1.52-2.98), disease-specific survival (HR = 1.53; 95%CI = 1.20-1.96), and disease-free survival (HR = 1.55; 95%CI = 1.10-2.17). The results of the subgroup analysis also support this conclusion.

CONCLUSION

Our results suggest that pretreatment anemia may be a prognostic biomarker for STS.

Establishment of an Academic Tissue Microarray Platform as a Tool for Soft Tissue Sarcoma Research

Soft tissue sarcoma (STS) is a heterogeneous family of rare mesenchymal tumors, characterized by histopathological and molecular diversity. Tissue microarray (TMA) is a tool that allows performing research in orphan diseases in a more efficient and cost-effective way. TMAs are paraffin blocks consisting of multiple small representative tissue cores from biological samples, for example, from multiple donors, diverse sites of disease, or multiple different diseases. In 2015, we began constructing TMAs using archival tumor material from STS patients. Specimens were well annotated in terms of histopathological diagnosis, treatment, and clinical follow-up of the tissue donors. Each TMA block contains duplicate or triplicate 1.0–1.5 mm tissue cores from representative tumor areas selected by sarcoma pathologists. The construction of TMAs was performed with TMA Grand Master (3DHistech). So far, we have established disease-specific TMAs from 7 STS subtypes: gastrointestinal stromal tumor (72 cases included in the array), alveolar soft part sarcoma (n = 12 + 47), clear cell sarcoma (n = 22 + 32), leiomyosarcoma (n = 55), liposarcoma (n = 42), inflammatory myofibroblastic tumor (n = 12 + 21), and alveolar rhabdomyosarcoma (n = 24). We also constructed a multisarcoma TMA covering a representative number of important histopathological subtypes on arrays for screening purposes, namely, angiosarcoma, dedifferentiated liposarcoma, pleomorphic liposarcoma, and myxoid liposarcoma, leiomyosarcoma, malignant peripheral nerve sheath tumor, myxofibrosarcoma, rhabdomyosarcoma, synovial sarcoma, and undifferentiated pleomorphic sarcoma, with 7–11 individual cases per subtype. We are currently expanding the list of TMAs with additional sarcoma entities, considering the heterogeneity of this family of tumors. Our extensive STS TMA platform is suitable for rapid and cost-effective morphological, immunohistochemical, and molecular characterization of the tumor as well as for the identification of potential novel diagnostic markers and drug targets. It is readily available for collaborative projects with research partners.

Meta-Analysis of Hematological Biomarkers as Reliable Indicators of Soft Tissue Sarcoma Prognosis

Background: Several recent studies have reported the reliable prognostic effect of hematological biomarkers in various tumors. Yet, the prognostic value of these hematological markers in soft tissue sarcoma (STS) remains inconclusive. Thus, the aim of this meta-analysis was to check the effect of hematological markers on the prognosis of STS. Methods: We systematically searched for relevant papers published before October 2019 in the PubMed and EMBASE databases. Overall survival (OS) and disease-specific survival (DSS) were the primary outcome, whereas disease-free survival was the secondary outcome. A thorough study of hazard ratios (HR) and 95% of confidence intervals (CIs) was done for determining the prognostic significance. Results: We performed 23 studies that comprised of 4,480 patients with STS. The results revealed that higher neutrophil-to-lymphocyte ratio (NLR), C-reactive protein (CRP), and platelet-to-lymphocyte ratio (PLR) were associated with poor OS/DFS (HR = 2.08/1.72, for NLR; HR = 1.92/1.75, for CRP, and HR = 1.86/1.61, for PLR). In contrast, a low lymphocyte-to-monocyte ratio (LMR) was relate to worse OS/DFS (HR = 2.01/1.90, for LMR). Moreover, pooled analysis illustrated that elevated NLR and CRP represents poor DSS, with HRs of 1.46 and 2.06, respectively. In addition, combined analysis revealed that higher Glasgow prognostic score (GPS) was linked to an adverse OS/DSS (HR = 2.35/2.77). Conclusion: Our meta-analysis suggested that hematological markers (NLR, CRP, PLR, LMR, and GPS) are one of the important prognostic indicators for patients affected by high-grade STS and patients with the STS being located in the extremity.

Prognostication in Mesenchymal Tumors: Can We Improve?

Prognostication in mesenchymal tumors can be challenging. They exhibit diverse, and sometimes overlapping, histologic features that are not always predictive of their true behavior. This article highlights examples of both traditional and emerging sarcoma biomarkers.

Clinical significance of the tail-like pattern in soft-tissue sarcomas on magnetic resonance imaging

BACKGROUND

An infiltrating abnormal signal around soft-tissue tumors along the fascial, neurovascular, or musculature plane on magnetic resonance imaging (T2-weighted, gadolinium-enhanced T1-weighted, or short-tau inversion recovery) is recognized as the "tail-like pattern". The tail-like pattern was intensively analyzed in myxofibrosarcoma, but not in other sarcomas. We aimed to answer some key questions about the tail-like pattern such as its incidence and effect on oncological outcomes.

METHODS

The presence of the tail-like pattern in 114 soft-tissue sarcomas was evaluated on T2-weighted images or gadolinium-enhanced T1-weighted images, or both. We analyzed the incidence of the tail-like pattern in all cases and in specific histological subtypes. We also assessed the clinical backgrounds of the presence of the tail-like pattern and its impact on achieving adequate surgical margins and oncological outcomes, including local recurrence and overall survival.

RESULTS

The tail-like pattern was detected in 50% of cases. The tail-like pattern was most common in myxofibrosarcoma and undifferentiated pleomorphic sarcoma, and less common in low-grade sarcomas. Trans-compartmental invasion of the tumor and high-grade malignancy were common clinical backgrounds for the presence of the tail-like pattern. The presence of the tail-like pattern significantly inhibits the achievement of preoperatively planned surgical margins despite planning the margins outside the tail-like pattern area. The tail-like pattern was an independent risk factor for local recurrence. The pattern was not an independent risk factor for worse overall survival, although it was a risk factor in univariate analysis.

CONCLUSION

The tail-like pattern is clinically significant in myxofibrosarcomas and other sarcomas with respect to the preoperative evaluation of malignancy by magnetic resonance imaging, and negatively affects successful resection and oncological outcomes. A more sophisticated modality for the evaluation and clinical management of the tail-like pattern is needed in the future.

Prognostic Significance of Apoptosis-related Markers in Patients With Soft-Tissue Sarcomas of Extremities

Bcl-2 and Bax proteins are key regulators of apoptosis, a process that is deregulated in many human diseases, particularly cancer. Overexpression of antiapoptotic Bcl-2 protein is associated with drug resistance and poor clinical outcome in cancer patients, whereas the expression of proapoptotic Bax protein, commonly detected in soft-tissue sarcoma (STS), is often associated with chemiosensitivity in different tumors. Studies on the clinical implications of apoptosis-related markers Bcl-2 and Bax in STS are limited. In this study, immunohistochemistry for Bcl-2 and Bax was performed on tissue microarrays of 86 multiple types of adult STS of the extremities. Bcl-2 and Bax positive expression was detected in 25.9% and 66.7% of the sarcomas, respectively. Overexpression of both, Bcl-2 and Bax, was directly associated with histologic grade and clinical stage. A significant association between Bax and Bcl-2 expression was also observed (P=0.007). The 5-year overall survival for the group was 57%, and it was lower for cases that overexpressed Bcl-2 (47.6% vs. 58.3%) and Bax (50% vs. 66.7%), although not statistically significant. After multivariate analysis, only the high histologic grade appeared as an independent prognostic factor for the patients (P=0.043; HR=8.0; 95% CI, 1.1-60.1). In our study, Bcl-2 and Bax expression was significantly associated with histologic grade and clinical stage, which are classic factors of poor prognosis. We suggest the use of these proteins as potential prognostic markers in STS of extremities.

Modeling synovial sarcoma metastasis in the mouse: PI3'-lipid signaling and inflammation

Solid tumor metastasis is a complex biology, impinged upon by a variety of dysregulated signaling pathways. PI3'-lipid signaling has been associated with metastasis and inflammation in many cancers, but the relationship between tumor cell-intrinsic PI3'-lipid signaling and inflammatory cell recruitment has remained enigmatic. Elevated PI3'-lipid signaling associates with progression of synovial sarcoma, a deadly soft tissue malignancy initiated by a t(X;18) chromosomal translocation that generates an SS18-SSX fusion oncoprotein. Here, we show in genetically engineered mouse models of locally induced expression of SS18-SSX1 or SS18-SSX2 that Pten silencing dramatically accelerated and enhanced sarcomagenesis without compromising synovial sarcoma characteristics. PTEN deficiency increased tumor angiogenesis, promoted inflammatory gene expression, and enabled highly penetrant spontaneous pulmonary metastasis. PTEN-deficient sarcomas revealed infiltrating myeloid-derived hematopoietic cells, particularly macrophages and neutrophils, recruited via PI3'-lipid-induced CSF1 expression in tumor cells. Moreover, in a large panel of human synovial sarcomas, enhanced PI3'-lipid signaling also correlated with increased inflammatory cell recruitment and CSF1R signal transduction in both macrophages and endothelial cells. Thus, both in the mouse model and in human synovial sarcomas, PI3'-lipid signaling drives CSF1 expression and associates with increased infiltration of the monocyte/macrophage lineage as well as neutrophils.

Analysis of Clinical and Molecular Factors Impacting Oncologic Outcomes in Undifferentiated Pleomorphic Sarcoma

BACKGROUND

Undifferentiated pleomorphic sarcomas (UPS) present a diagnostic and therapeutic challenge. Identification of prognostic molecular markers is required for the discovery of novel treatment approaches. The purpose of this study was to correlate clinicopathologic variables, expression of tyrosine kinase receptors, and markers of cell cycle progression and survival with oncologic outcomes.

METHODS

A tissue microarray containing 208 primary UPS samples was analyzed by immunohistochemistry for protein markers and in situ hybridization for microRNA. Staining results were correlated with clinicopathologic features and oncologic outcomes. Univariate and multivariate analyses were conducted to assess associations between expression of protein markers, mi-RNA, and outcome.

RESULTS

At a median follow-up of 3.9 years (9 years for survivors), 5-year disease-specific survival (DSS) was 63 %. Clinical variables associated with improved DSS included age <61 years, tumor size <10 cm, margin-negative resection, and sporadic-tumor status. At the protein level, loss of cyclin D1 (p = 0.06), pEGFR (p = 0.023), pIGF-1R (p = 0.022), and PTEN (p < 0.001) and overexpression of AXL (p = 0.015) were associated with reduced DSS on univariate analysis. Ki67, PCNA, and pEGFR were more highly expressed in sporadic UPS than radiation-associated (RA-UPS), whereas RA-UPS samples expressed higher levels of both phosphorylated and total IGF-1R.

DISCUSSION

Loss of cyclin D1, overexpression of AXL, and loss of PTEN are associated with poor cancer-specific outcomes and warrant further investigation in UPS. The differences in protein expression in sporadic versus RA-UPS may indicate that the activated molecular signaling nodes may be different for each specific histology and also could explain the aggressive phenotype seen in RA-UPS compared with the sporadic lesions.

Extensive survey of STAT6 expression in a large series of mesenchymal tumors

OBJECTIVES

Expression of strong nuclear STAT6 is thought to be a specific marker for solitary fibrous tumors (SFTs). Little is known about subtle expression patterns in other mesenchymal lesions.

METHODS

We performed immunohistochemical studies against the C-terminus of STAT6 in tissue microarrays and whole sections, comprising 2366 mesenchymal lesions.

RESULTS

Strong nuclear STAT6 was expressed in 285 of 2,021 tumors, including 206 of 240 SFTs, 49 of 408 well-differentiated/dedifferentiated liposarcomas, eight of 65 unclassified sarcomas, and 14 of 184 desmoid tumors, among others. Expression in SFTs was predominately limited to the nucleus. Other positive tumors typically expressed both nuclear and cytoplasmic STAT6. Complete absence of STAT6 was most common in pleomorphic liposarcoma and alveolar soft part sarcoma (60% and 72% cases negative, respectively).

CONCLUSIONS

Strong nuclear STAT6 is largely specific for SFTs. Physiologic low-level cytoplasmic/nuclear expression is common in mesenchymal neoplasia and is of uncertain significance.

Toward better soft tissue sarcoma staging: building on american joint committee on cancer staging systems versions 6 and 7

BACKGROUND

Based on review of patient data in case conferences over time, we hypothesized that clinically relevant data are omitted in routine soft tissue sarcoma staging.

METHODS

We examined subsets of a prospectively collected single institution soft tissue sarcoma database with respect to criteria of the AJCC versions 6 (2002) and 7 (2010) staging systems and examined their clinical outcomes.

RESULTS

Relapse-free survival decreases with increasing primary tumor size in four categories, versus two categories used in AJCC 6 and 7 staging. Disease-specific survival decreases over three categories. Conversely, omission of tumor depth as a prognostic factor in version 7 appears supported, since tumor depth is not an independent risk factor for disease-specific survival by multivariate analysis. Patients with nodal disease and no other metastases fare better than patients with other metastases, but have inferior outcomes compared with patients with large high-grade tumors without nodal metastasis. Multivariate analysis identified size, site, grade, age, nodal metastatic disease, and other metastatic disease as independent risk factors for disease-specific survival. Versions 6 and 7 criteria are tacit regarding anatomic site and histology for tumors with identical FNCLCC grade.

CONCLUSIONS

Improved patient risk assessment may be achieved by staging using a larger number of size categories. Staging system refinements come at the cost of a larger number of staging categories. Histology or site-specific staging systems, nomograms or Bayesian belief networks may provide more accurate means to assess clinical outcomes.

Unphosphorylated STAT1 promotes sarcoma development through repressing expression of Fas and bad and conferring apoptotic resistance

STAT1 exists in phosphorylated (pSTAT1) and unphosphorylated (uSTAT1) forms each regulated by IFN-γ. Although STAT1 is a key mediator of the IFN-γ signaling pathway, an essential component of the host cancer immunosurveillance system, STAT1 is also overexpressed in certain human cancers where the functions of pSTAT1 and uSTAT1 are ill defined. Using a murine model of soft tissue sarcoma (STS), we show that disruption of the IFN effector molecule IRF8 decreases pSTAT1 and increases uSTAT1 in STS cells, thereby increasing their metastatic potential. We determined that the IRF8 gene promoter was hypermethylated frequently in human STS. An analysis of 123 human STS specimens revealed that high uSTAT1 levels in tumor cells was correlated with a reduction in disease-specific survival (DSS), whereas high pSTAT1 levels in tumor cells were correlated with an increase in DSS. In addition, uSTAT1 levels were negatively correlated with pSTAT1 levels in these STS specimens. Mechanistic investigations revealed that IRF8 suppressed STAT1 transcription by binding the STAT1 promoter. RNAi-mediated silencing of STAT1 in STS cells was sufficient to increase expression of the apoptotic mediators Fas and Bad and to elevate the sensitivity of STS cells to Fas-mediated apoptosis. Together, our findings show how the phosphorylation status of pSTAT1 determines its function as a tumor suppressor, with uSTAT1 acting as a tumor promoter that acts by elevating resistance to Fas-mediated apoptosis to promote immune escape.

The expression of c-Met pathway components in unclassified pleomorphic sarcoma/malignant fibrous histiocytoma (UPS/MFH): a tissue microarray study

AIMS

Subclassification of undifferentiated pleomorphic sarcoma/malignant fibrous histiocytoma (UPS/MFH) into distinct biological cohorts based on the expression patterns of molecular markers can identify patient subsets with especially unfavourable clinical outcomes. Identification of molecular prognosticators amenable for drug targeting can facilitate rational development of UPS/MFH tailored therapies. The aim was to evaluate expression of c-Met pathway components in a large cohort of UPS/MFH samples.

METHODS AND RESULTS

An immunohistochemical analysis for hepatocyte growth factor (HGF), c-Met, phospho-c-Met (pc-Met), phospho-mitogen-activated protein kinase kinase (MAPKK) also known as mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK) kinase (p-MEK) and phospho-protein kinase B (p-AKT) was performed on a clinically annotated tissue microarray of 158 UPS/MFH samples. Univariable and multivariable analyses were conducted to evaluate the correlation of molecular variables with UPS/MFH disease specific survival. All evaluated markers were expressed in UPS/MFH to varying levels. Most importantly, strong HGF, pc-Met, p-MEK and p-AKT expression correlated significantly with dismal patient outcome on univariable statistical analysis. Expression of p-MEK and p-AKT remained statistically significant independent prognosticators on multivariable analysis.

CONCLUSIONS

c-Met pathway components and especially p-MEK and p-AKT are potential prognostic biomarkers for UPS/MFH; their inclusion in future molecular-based staging systems should be evaluated. Furthermore, novel approaches targeting HGF, c-Met, MEK/extracellular-regulated kinase (ERK) and/or AKT should be considered for a subset of UPS/MFH patients.