Martin Jaeger

Siglec-15 has recently emerged as an important regulator at the interface of glyco-immunology and cancer-immunology. The transmembrane immune receptor links cancer-associated glycosylation to immune suppression in the tumor microenvironment (TME). Siglec-15 signals through the adapter protein DAP12, using its immunoreceptor tyrosine-based activation motif to induce signaling. While typically expressed by osteoclasts, increased expression of Siglec-15 holds critical implications for tumor-associated macrophages (TAMs). Current evidence suggests that Siglec-15 modulates anti-tumor immunity via reprogramming of TAMs toward an M2-like, protumorigenic phenotype characterized by direct suppression of effector T cells through interleukin-10 and transforming growth factor-β production. Identification of its ligands is ongoing, but Siglec-15 has been shown to interact both with N-linked and O-linked sialoglycans and binding can be enhanced by glycan sulfation. In addition, ligand specificity appears to be determined by glycan presentation on specific glycoprotein scaffolds, among others found in CD44 and CD11b. Siglec-15 expression is detected in many solid and hematological cancers and has been shown to negatively correlate with programmed cell death protein 1/programmed death-ligand 1 expression in several studies, providing rationale for targeting this Siglec. Defining the physiological and cancer-associated ligands of Siglec-15 is critical for understanding its signaling and the functional consequences thereof. Blocking antibodies for Siglec-15 show promising effects in (pre)clinical studies. Here, we provide an overview of current insights into the glycan ligands of Siglec-15, discuss its role in controlling TAMs phenotypes, and functions in the TME. Moreover, we discuss current therapeutic strategies aimed at targeting Siglec-15 and its glycan ligands in cancer immunotherapy.

Objectives: To describe typical MRI findings 1 year after reverse total shoulder arthroplasty (rTSA) implantation. Materials and methods: Metal artifact reduction (MARS) MRI including CSSEMAC techniques was prospectively acquired in N = 25 consecutive patients (18/25 female; 61–80 years) 1 year after rTSA. MRI findings of bone and soft tissue and artifact reduction were assessed semi-quantitatively. Clinical Constant-Murley scores (CMS) were obtained, including its subscores pain, activities-of-daily-living (ADL), range-of-motion (ROM), and strength. Preoperative MRI was available in 13/25 subjects. Statistical analyses included descriptive statistics, Spearman correlations, nonparametric tests, and multivariable regression models. Results: MARS MRI of rTSA showed overall good image quality. Subacromial edema (88%), mild effusion (52%), and synovitis (44%) were frequent postoperative findings. Synovitis was associated with more pain ( B = −2.044, 95% CI [−3.617, −0.470], p = 0.039) and lower strength ( B = −4.497, 95% CI [−7.101, −1.893], p = 0.008). Minor bone marrow edema (BME) at the shaft was found in all subjects (100%). BME in Gruen zone 4 (88%) and 6 (80%) was most frequent. A higher number of Gruen zones with BME correlated significantly with lower ADL ( R = −0.532, p = 0.024). There was a significant increase in fatty infiltration between pre- and postoperative images for the midacromial deltoid muscle (1 (IQR, 1–1) versus 2 (IQR, 1–2), p = 0.008; postoperatively present 100%). It was associated with an increase in deltoid length (chi-square 4.35, p = 0.037), but not with inferior clinical scores. However, fatty infiltration of the more anterior deltoid muscle was associated with lower ADL ( B = −3.064, p = 0.008). Conclusion: Subacromial edema, minor shaft BME, and fatty infiltration of the midacromial deltoid muscle were typical, asymptomatic MRI findings 1 year after rTSA.

Background: Reoperation rates in clavicular fractures and acromioclavicular (AC) joint dislocations are high, often indicated for plate removal due to plate prominence and poor cosmesis. The recently designed 2.7 mm variable angle locking compression plate (VA-LCP®) Clavicle Plate and 2.7 mm VA-LCP® Clavicle Hook Plate (J&J MedTech) are intended to have an improved plate-to-bone fit, are precontoured, and have a low profile. Additionally, the Clavicle Hook Plate has a more anatomically adapted hook design to reduce the risk of painful osteolysis leading to earlier plate removals. All screw holes in these plates accept 2.7 mm screws. Primary objectives of this observational, post-marketing, prospective, multicenter case series are to gather early and mid- to long-term evidence on the clinical performance, safety, and usability of the 2.7 mm VA-LCP Clavicle Plates and 2.7 mm VA-LCP Clavicle Hook Plates, specifically to describe (1) safety, (2) clinical performance, (3) functional outcomes, (4) patient-reported outcomes (PROs) and (5) usability and surgeons' experience with the devices. Methods: Approximately 76 patients with clavicle fractures and primary surgical treatment with the 2.7 mm VA-LCP Clavicle Plate or 2.7 mm VA-LCP Clavicle Hook Plate will be enrolled prospectively over 15 months. Outcome measures include adverse events related/potentially related to the investigational device, clinical performance, functional outcomes (QuickDASH), PROs (PROMIS® upper extremity score, local pain, discomfort, and plate prominence), and radiographic outcomes. Data will be collected at baseline, 2w, 6w, 3m, 6m, 1y and 2y after surgery. The surgeons' experience with and perceived utility of the devices will be surveyed. Interim analysis will be performed when 30 patients per group have reached 6 months after surgery. Long-term outcomes will be evaluated using 2-year follow-up results. A Statistical Analysis Plan will be prepared before final analysis summarizing the descriptive statistics to be used. Discussion: The study described in this protocol on patients with clavicular fracture or AC joint dislocations undergoing surgical fracture fixation aims to gather first evidence on the clinical performance, safety, and usability of the 2.7 mm VA-LCP Clavicle Plates and 2.7 mm VA-LCP Clavicle Hook Plate Systems. This study will provide valuable data from a standard-of-care setting and may help design future comparative studies for relevant performance parameters. Clinical Trial Registration: https://clinicaltrials.gov/study/NCT04921865?term=NCT04921865%20&rank=1 , identifier NCT04921865.

Aims: Trained immunity, defined as long-term functional reprogramming of innate immune cells, has been implicated in the heterologous protective effects of certain vaccines against infection and cancer. AS01-adjuvanted vaccines have been suggested to provide such heterologous protective effects. We therefore aimed to investigate the capacity of AS01 to induce trained immunity and evaluated its potential as an antitumoral therapeutic. Methods: Acute cytokine production was assessed in human monocytes after AS01 stimulation. Trained immunity was subsequently evaluated by interleukin-6 (IL-6) and tumor necrosis factor (TNF) quantification following heterologous restimulation. Antitumor efficacy of AS01 was assessed in mice bearing B16-F10 melanoma, MB49 bladder cancer, or Lewis lung carcinoma by monitoring tumor growth. Immune phenotyping of B16-F10 and MB49 tumor microenvironments was determined with flow cytometry. Results: Although AS01 did not stimulate acute inflammation, it induced trained immunity, marked by increased responsiveness upon secondary stimulation in human monocytes. Treatment of mice bearing B16-F10 melanoma or MB49 bladder cancer with AS01 strongly diminished tumor growth, whereas no effect was observed in the Lewis lung carcinoma model. In these responsive models, the antitumor effects of AS01 were associated with an altered tumor microenvironment, characterized by increased infiltration of CD8+ T cells, regulatory T cells, neutrophils, and monocytes, along with a decrease in tumor-associated macrophages. AS01 also decreased expression of immune checkpoint protein PD-L1 in monocytes and neutrophils, suggesting enhanced antitumor immune responsiveness. Conclusion: Our findings show the capacity of AS01 to induce trained immunity and support its potential to be repurposed as an immunotherapeutic approach for cancer.

Introduction Tyrosine kinase inhibitors, including lenvatinib approved for advanced non-medullary thyroid cancer (TC), affect the immune system. As tumor-related inflammation contributes to TC pathogenesis, this study assesses the immunomodulatory effects of lenvatinib, focusing on myeloid cells. Methods Peripheral blood was collected from 16 lenvatinib-treated and 15 untreated TC patients (cross-sectional cohort), and from eight patients before and after > 1 month of lenvatinib (longitudinal cohort). Immune profiling included cell subset counts, proteomic analyses, and ex vivo cytokine assays in peripheral blood mononuclear cells (PBMCs) and monocytes. Monocytes from healthy donors were used to evaluate metabolic activity, reactive oxygen species (ROS) production, and phagocytosis. Tumor-intrinsic effects of lenvatinib were studied by proteomics and immunophenotyping of the TPC-1 cell line. Results Lenvatinib increased lymphocytes and reduced neutrophils. In both cohorts, lenvatinib modulated the inflammatory proteome with elevated VEGFA, CCL11, MMP-10, and TRAIL. Monocytes exposed ex vivo to lenvatinib showed reduced production of IL-1β, IL-6, IL-8, and IL-10. In patients treated with lenvatinib, monocytes displayed increased IL-1Ra and TNF, while PBMCs exhibited enhanced IFN-γ production. Monocytes from healthy donors displayed reduced glycolysis and increased ROS after lenvatinib exposure. In TPC-1 cells, lenvatinib altered the secretome and upregulated MHC class I, PD-L1, and CD40. Conclusions Lenvatinib treatment has broad immunomodulatory effects in patients with TC, including shifts in immune cell populations, changes in the proteome, and reprogramming of cytokine responses. Lenvatinib also impacts monocyte metabolism and tumor cell phenotype. These findings provide insight into the multifaceted immunological activities of lenvatinib and highlight opportunities for treatment strategies. Trial registration Not applicable, this is a noninterventional trial.

Chronic inflammation plays a key role in cancer pathogenesis. Aggressive thyroid cancer is associated with immune infiltration and systemic inflammation. Long pentraxin 3 (PTX3) is an inflammatory protein implicated in tumor progression. This study evaluates PTX3 plasma levels in patients with non-medullary thyroid cancer (TC) compared to benign thyroid disease and investigates its tissue expression. We prospectively included 55 TC patients: 42 papillary, 3 follicular, 4 oncocytic, 4 anaplastic (ATC), and 2 poorly differentiated (PDTC). The control group consisted of 32 patients with benign thyroid disease. PTX3 plasma concentrations were measured by ELISA, and tissue expression of PTX3 and CD68 was analyzed using immunohistochemistry. PTX3 plasma levels did not significantly differ between TC and controls, but patients with PDTC and ATC had markedly higher concentrations. Tissue analysis showed strong PTX3 expression in three of four ATC cases in tumor and stromal cells, whereas benign and differentiated thyroid tissues exhibited minimal staining. CD68 expression was positive in ATC, indicating tumor-associated macrophage infiltration, but a few cells were double-positive for PTX3 and CD68. Our findings suggest a possible association between PTX3 and aggressive TC, particularly ATC. Further studies are needed to validate these findings and elucidate the cellular origin and functional role of PTX3.

Anaplastic thyroid cancer (ATC) is an aggressive and rare disease. Rapid metastasis and limited treatments call for additional therapeutic options, including drug repurposing. The early spreading of ATC highlights the importance of rapid therapy success assessment, which could be achieved by measurement of extracellular vesicle (EV)-associated cell-free RNA in liquid biopsy samples. Recent studies have discovered the potential of the receptor tyrosine kinase inhibitor vandetanib for ATC treatment in vitro and in vivo. Given the rarity of ATC patients receiving off-label vandetanib treatment, acquiring patient samples for clinical studies is a prolonged process, and pre-clinical investigations are needed to elucidate the effects of vandetanib on ATC cells. Here, we present an in vitro study addressing holistic transcriptional and proteomic changes induced in the ATC cell line Cal62 by three doses of vandetanib and quantified by high-throughput methods. By comparing the transcriptional and proteomic data sets and applying dimensional reduction models such as sparse partial least-squares discriminant analysis, we refined a set of 21 biomarker candidates. Out of these, we report a final signature of eight transcriptional biomarkers, validated in cellular and cell-free RNA by RT-qPCR and verified for biological significance and discriminatory power by pathway over-representation analysis and partial least-squares regression. This transcriptional biomarker signature can distinguish vandetanib treatment from control in cell-free RNA isolated from Cal62 EVs and can be measured reliably, easily, and quickly using RT-qPCR. Our findings may serve as a basis for future clinical trials with liquid biopsy samples from ATC patients undergoing off-label vandetanib treatment.

Background and objectives: Chronic inflammation plays a key role in cancer patho-genesis. Long pentraxin 3 (PTX3) is an inflammatory protein implicated in tumor pro-gression. Aggressive thyroid cancer is associated with immune infiltration and sys-temic inflammation. This study evaluates PTX3 plasma levels in patients with non-medullary thyroid cancer (TC) compared to benign thyroid diseases and investi-gates its tissue expression. Methods: We prospectively included 55 TC patients (41 preoperative, 14 recurrent) with various subtypes: 42 papillary, 3 follicular, 4 oncocyt-ic, 4 anaplastic (ATC), and 2 poorly differentiated (PDTC). A control group of 32 pa-tients with benign thyroid diseases (20 goiter, 12 autoimmune thyroiditis) was includ-ed. PTX3 plasma concentrations were measured by ELISA, and tissue expression of PTX3 and CD68, a macrophage marker, was analyzed using immunohistochemistry. Results: PTX3 plasma levels did not significantly differ between TC and controls, but patients with PDTC and ATC had markedly higher concentrations. Tissue analysis showed strong PTX3 expression in three of four ATC cases in tumor and stromal cells, whereas benign and differentiated thyroid tissues exhibited minimal staining. CD68 expression was positive in ATC, indicating tumor-associated macrophage infiltration. However, few cells were double-positive for PTX3 and CD68, suggesting PTX3 origi-nates from tumor, stromal cells, or other immune cells rather than macrophages. Conclusions: Our findings suggest that PTX3 is associated with aggressive thyroid cancer, particularly ATC. Further studies are needed to elucidate its role in tumor progression and the inflammatory microenvironment.

Background: Anaplastic thyroid cancer (ATC) is an aggressive and rare disease. Rapid metastasis and limited treatments call for additional therapeutic options, including drug repurposing. The early spreading of ATC highlights the importance of rapid therapy success assessment, which could be achieved by measurement of extracellular vesicle (EV)-associated cell-free RNA in liquid biopsy samples. Recent studies have discovered the potential of the receptor tyrosine kinase inhibitor vandetanib for ATC treatment in vitro and in vivo . Given the rarity of ATC patients receiving off-label vandetanib treatment, acquiring patient samples for clinical studies is a prolonged process, and pre-clinical investigations are needed to elucidate the effects of vandetanib on ATC cells. Objective: Here, we present an in vitro study addressing holistic transcriptional and proteomic changes induced in the ATC cell line Cal62 by three doses of vandetanib and quantified by high-throughput methods. Methods: By comparing the transcriptional and proteomic data sets and applying dimensional reduction models such as sparse partial least-squares discriminant analysis, we refined a set of 21 biomarker candidates. Results: Out of these, we report a final signature of eight transcriptional biomarkers, validated in cellular and cell-free RNA by RT-qPCR and verified for biological significance and discriminatory power by pathway over-representation analysis and partial least-squares regression. This transcriptional biomarker signature can distinguish vandetanib treatment from control in cell-free RNA isolated from Cal62 EVs and can be measured reliably, easily, and quickly using RT-qPCR. Conclusions: Our findings may serve as a basis for future clinical trials with liquid biopsy samples from ATC patients undergoing off-label vandetanib treatment.

Vulvovaginal candidiasis (VVC) affects up to 75% of women at least once during their lifetime, and up to 8% of women suffer from frequent recurrent episodes of VVC (RVVC). A lack of a protective host response underlies vaginal Candida infections, while a dysregulated hyperinflammatory response may drive RVVC. This study aimed to investigate the systemic inflammatory protein profile in women with RVVC in an African population, considering the potential influence of hormonal contraceptive use on systemic inflammation. Using multiplex Proximity Extension Assay technology, we measured 92 circulatory inflammatory proteins in plasma samples from 158 RVVC patients and 92 asymptomatic women (controls). Hormonal contraceptive use was not found to have a statistically significant correlation with a systemic inflammatory protein profile in either RVVC patients or the asymptomatic women. RVVC women had lower circulating Fibroblast Growth Factor 21 (FGF-21) concentrations compared with healthy controls (adjusted p value = 0.028). Reduced concentrations of FGF-21 may be linked to the immune pathology observed in RVVC cases through IL-1β. This study may help to identify new biomarkers for the diagnosis and future development of novel immunomodulatory treatments for RVVC.