Pentraxin 3, a new biomarker for the diagnosis and management of PJI in primary and revision hip arthroplasty.

Background/Aim of the study: The periprosthetic or superficial site infections are one of the most catastrophic and difficult to manage complications following total hip arthroplasty. Recently, in addition to well know systemic markers of inflammation, the blood and synovial fluid biomarkers are focused to have a possible role in the infection diagnosis. The long Pentraxin 3 (PTX3) seems to be a sensitive biomarker of acute phase inflammation. The objectives of this prospective and multicentre study were (1) to establish the plasma trend effectiveness of PTX3 in patients undergoing primary hip replacement, and (2) to evaluate the diagnostic accuracy of blood and synovial PTX3 in patients undergoing prosthetic revision of infected hip arthroplasty. METHODS: Human PTX3 was measured by ELISA in two cohorts of patients, 10 patients undergoing primary hip replacement for osteoarthritis and 9 patients with infected hip arthroplasty. RESULTS: The Authors were able to demonstrate that PTX3 is a viable biomarker for acute phase inflammation. CONCLUSIONS: An increase in PTX3 protein concentration in the synovial fluid of patients undergoing implant revision has a strong diagnostic capacity for periprosthetic joint infection, showing 97% specificity.

Long Pentraxin 3 as a New Biomarker for Diagnosis of Hip and Knee Periprosthetic Joint Infections.

BACKGROUND: Preoperative diagnosis of periprosthetic joint infections (PJIs) poses an unmet clinical challenge. The long pentraxin PTX3 is a component of the innate immune system involved in infection immunity. This study evaluated the potential of synovial and plasmatic PTX3 in the diagnosis of hip and knee PJIs. METHODS: Consecutive total hip and knee arthroplasty (THA/TKA) revisions were prospectively included and classified as septic or aseptic according to the European Bone and Joint Infection Society (EBJIS) and Musculoskeletal Infection Society (MSIS) criteria. The concentration of PTX3 in plasma and synovial fluid samples was measured with ELISA. The AUC, threshold value, sensitivity, specificity, and positive and negative likelihood ratios were calculated using the ROC (receiver operating characteristic) curve method. RESULTS: The study population included 128 patients (94 THAs; 34 TKAs). The AUC of the synovial PTX3 based on EBJIS criteria was 0.85 (p < 0.0001), with a sensitivity of 81.13% and a specificity of 93.33%. The AUC based on MSIS criteria was 0.95 (p < 0.001), with a sensitivity of 91.43% and a specificity of 89.25%. Plasmatic PTX3 failed to discriminate infected from non-infected patients. CONCLUSIONS: Synovial PTX3 demonstrated an excellent diagnostic potential in hip and knee PJIs, with a very high specificity irrespective of the diagnostic criteria for PJI.

Size-advantage of monovalent nanobodies against the macrophage mannose receptor for deep tumor penetration and tumor-associated macrophage targeting.

Rationale: Nanobodies (Nbs) have emerged as an elegant alternative to the use of conventional monoclonal antibodies in cancer therapy, but a detailed microscopic insight into the in vivo pharmacokinetics of different Nb formats in tumor-bearers is lacking. This is especially relevant for the recognition and targeting of pro-tumoral tumor-associated macrophages (TAMs), which may be located in less penetrable tumor regions. Methods: We employed anti-Macrophage Mannose Receptor (MMR) Nbs, in a monovalent (m) or bivalent (biv) format, to assess in vivo TAM targeting. Intravital and confocal microscopy were used to analyse the blood clearance rate and targeting kinetics of anti-MMR Nbs in tumor tissue, healthy muscle tissue and liver. Fluorescence Molecular Tomography was applied to confirm anti-MMR Nb accumulation in the primary tumor and in metastatic lesions. Results: Intravital microscopy demonstrated significant differences in the blood clearance rate and macrophage targeting kinetics of (m) and (biv)anti-MMR Nbs, both in tumoral and extra-tumoral tissue. Importantly, (m)anti-MMR Nbs are superior in reaching tissue macrophages, an advantage that is especially prominent in tumor tissue. The administration of a molar excess of unlabelled (biv)anti-MMR Nbs increased the (m)anti-MMR Nb bioavailability and impacted on its macrophage targeting kinetics, preventing their accumulation in extra-tumoral tissue (especially in the liver) but only partially influencing their interaction with TAMs. Finally, anti-MMR Nb administration not only allowed the visualization of TAMs in primary tumors, but also at a distant metastatic site. Conclusions: These data describe, for the first time, a microscopic analysis of (m) and (biv)anti-MMR Nb pharmacokinetics in tumor and healthy tissues. The concepts proposed in this study provide important knowledge for the future use of Nbs as diagnostic and therapeutic agents, especially for the targeting of tumor-infiltrating immune cells.

Oncogenic KRAS-Induced Protein Signature in the Tumor Secretome Identifies Laminin-C2 and Pentraxin-3 as Useful Biomarkers for the Early Diagnosis of Pancreatic Cancer.

KRAS mutations characterize pancreatic cell transformation from the earliest stages of carcinogenesis, and are present in >95% of pancreatic ductal adenocarcinoma (PDAC) cases. In search of novel biomarkers for the early diagnosis of PDAC, we identified the proteins secreted by the normal human pancreatic cell line (HPDE) recently transformed by inducing the overexpression of the KRASG12V oncogene. We report a proteomic signature of KRAS-induced secreted proteins, which was confirmed in surgical tumor samples from resected PDAC patients. The putative diagnostic performance of three candidates, Laminin-C2 (LAMC2), Tenascin-C (TNC) and Pentraxin-3 (PTX3), was investigated by ELISA quantification in two cohorts of PDAC patients (n = 200) eligible for surgery. Circulating levels of LAMC2, TNC and PTX3 were significantly higher in PDAC patients compared to the healthy individuals (p < 0.0001). The Receiver Operating Characteristics (ROC) curve showed good sensitivity (1) and specificity (0.63 and 0.85) for LAMC2 and PTX3, respectively, but not for TNC, and patients with high levels of LAMC2 had significantly shorter overall survival (p = 0.0007). High levels of LAMC2 and PTX3 were detected at early stages (I−IIB) and in CA19-9-low PDAC patients. In conclusion, pancreatic tumors release LAMC2 and PTX3, which can be quantified in the systemic circulation, and may be useful in selecting patients for further diagnostic imaging.

PLGA Based Nanoparticles for the Monocyte-Mediated Anti-Tumor Drug Delivery System.

Together with the development of new therapeutic agents, innovation in the delivery system of anti-tumor drugs is required to increase tumor-specificity and avoid unexpected toxicity. To achieve higher efficiency, we combined a live cell-mediated drug delivery system with nanotechnology, with the aim to prove that blood monocytes can be a cargo to deliver antitumor drugs encapsulated in Polymeric poly(D, L-lactide-co-glycolide) acid based nanoparticles (PLGA NPs). In this study, we have characterized how isolated purified monocytes efficiently internalize PLGA-NPs and have imaged in vivo their trafficking upon intravenous injection in tumor-bearing mice. Monocytes carrying PLGA-Cy7 NPs were able to reach the tumor site, with superior efficiency than free PLGA-Cy7 NPs, and the bio-distribution analysis confirmed that tumors were the most reached among peripheral tissues. We further demonstrate that monocytes carrying Doxorubicin encapsulated PLGA NPs (PLGA-Doxo) induced strong killing of co-cultured tumor cells. Our studies provide proof-of-concept evidence that monocytes can be exploited in approaches of live cell-mediated drug delivery systems for tumor therapy.

Metabolome of Pancreatic Juice Delineates Distinct Clinical Profiles of Pancreatic Cancer and Reveals a Link between Glucose Metabolism and PD-1+ Cells.

Better understanding of pancreatic diseases, including pancreatic ductal adenocarcinoma (PDAC), is an urgent medical need, with little advances in preoperative differential diagnosis, preventing rational selection of therapeutic strategies. The clinical management of pancreatic cancer patients would benefit from the identification of variables distinctively associated with the multiplicity of pancreatic disorders. We investigated, by 1H nuclear magnetic resonance, the metabolomic fingerprint of pancreatic juice (the biofluid that collects pancreatic products) in 40 patients with different pancreatic diseases. Metabolic variables discriminated PDAC from other less aggressive pancreatic diseases and identified metabolic clusters of patients with distinct clinical behaviors. PDAC specimens were overtly glycolytic, with significant accumulation of lactate, which was probed as a disease-specific variable in pancreatic juice from a larger cohort of 106 patients. In human PDAC sections, high expression of the glucose transporter GLUT-1 correlated with tumor grade and a higher density of PD-1+ T cells, suggesting their accumulation in glycolytic tumors. In a preclinical model, PD-1+ CD8 tumor-infiltrating lymphocytes differentially infiltrated PDAC tumors obtained from cell lines with different metabolic consumption, and tumors metabolically rewired by knocking down the phosphofructokinase (Pfkm) gene displayed a decrease in PD-1+ cell infiltration. Collectively, we introduced pancreatic juice as a valuable source of metabolic variables that could contribute to differential diagnosis. The correlation of metabolic markers with immune infiltration suggests that upfront evaluation of the metabolic profile of PDAC patients could foster the introduction of immunotherapeutic approaches for pancreatic cancer.

Senescent thyrocytes and thyroid tumor cells induce M2-like macrophage polarization of human monocytes via a PGE2-dependent mechanism.

BACKGROUND: Thyroid carcinoma includes several variants characterized by different biological and clinical features: from indolent microcarcinoma to undifferentiated and aggressive anaplastic carcinoma. Inflammation plays a critical role in thyroid tumors. Conditions predisposing to cancer, as well as oncogene activity, contribute to the construction of an inflammatory microenvironment that facilitates thyroid tumor progression. Moreover, oncogene-induced senescence, a mechanism tightly connected with inflammation, and able to restrain or promote cancer progression, is involved in thyroid cancer. The interactions between thyroid tumor cells and the microenvironment are not completely clarified. METHODS: We characterize in vitro the interplay between macrophages and senescent thyrocytes and tumor-derived cell lines, modeling early and late thyroid tumor stages, respectively. Purified peripheral blood-derived human monocytes were exposed to thyroid cell-derived conditioned medium (CM) and assessed for phenotype by flow cytometry. The factors secreted by thyroid cells and macrophages were identified by gene expression analysis and ELISA. The protumoral effect of macrophages was assessed by wound healing assay on K1 thyroid tumor cells. The expression of PTGS2 and M2 markers in thyroid tumors was investigated in publicly available datasets. RESULTS: Human monocytes exposed to CM from senescent thyrocytes and thyroid tumor cell lines undergo M2-like polarization, showing high CD206 and low MHC II markers, and upregulation of CCL17 secretion. The obtained M2-like macrophages displayed tumor-promoting activity. Among genes overexpressed in polarizing cells, we identified the prostaglandin-endoperoxide synthase enzyme (PTGS2/COX-2), which is involved in the production of prostaglandin E2 (PGE2). By using COX-2 inhibitors we demonstrated that the M2-like polarization ability of thyroid cells is related to the production of PGE2. Co-expression of PTGS2 and M2 markers is observed a significant fraction of human thyroid tumors. CONCLUSIONS: Our results demonstrate that both senescent thyrocytes and thyroid tumor cell lines trigger M2-like macrophage polarization that is related to PGE2 secretion. This suggests that the interaction with the microenvironment occurs at both early and late thyroid tumor stages, and favors tumor progression. The co-expression of PTGS2 gene and M2 markers in human thyroid carcinoma highlights the possibility to counteract tumor growth through COX-2 inhibition.

Optical in vivo imaging detection of preclinical models of gut tumors through the expression of integrin αVß3.

Optical imaging and Fluorescent Molecular Tomography (FMT) are becoming increasingly important for the study of different preclinical models of cancer, providing a non-invasive method for the evaluation of tumor progression in a relatively simple and fast way. Intestinal tumors, in particular colorectal cancer (CRC), represent a major cause of cancer-related death in Western countries: despite the presence of a number of preclinical models of intestinal carcinogenesis, there is a paucity of information about the possibility to detect intestinal tumors using fluorescent probes and optical in vivo imaging. Herein, we identify the detection of integrin αvß3 by FMT and optical imaging as an effective approach to assess the occurrence and progression of intestinal carcinogenesis in genetic and chemically-induced mouse models. For this purpose, a commercially available probe (IntegriSense), recognizing integrin αvß3, was injected in APC+/min mice bearing small intestinal adenomas or CRC: FMT analysis allowed a specific tumor detection, further confirmed by subsequent ex vivo imaging or conventional histology. In addition, IntegriSense detection by FMT allowed the longitudinal monitoring of tumor growth. Taken together, our data indicate the possibility to use integrin αvß3 for the visualization of intestinal tumors in preclinical models.