An aza-macrocycle containing maltolic side-arms (maltonis) as potential drug against human pediatric sarcomas.

BACKGROUND: Identification of new drugs against paediatric sarcomas represents an urgent clinical need that mainly relies on public investments due to the rarity of these diseases. In this paper we evaluated the in vitro and in vivo efficacy of a new maltol derived molecule (maltonis), belonging to the family of molecules named hydroxypyrones. METHODS: Maltonis was screened for its ability to induce structural alteration of DNA molecules in comparison to another maltolic molecule (malten). In vitro antitumour efficacy was tested using a panel of sarcoma cell lines, representative of Ewing sarcoma, osteosarcoma and rhabdomyosarcoma, the three most common paediatric sarcomas, and in normal human mesenchymal primary cell cultures. In vivo efficacy was tested against TC-71 Ewing sarcoma xenografts. RESULTS: Maltonis, a soluble maltol-derived synthetic molecule, was able to alter the DNA structure, inhibit proliferation and induce apoptotic cell death in paediatric sarcoma cells, either sensitive or resistant to some conventional chemotherapeutic drugs, such as doxorubicin and cisplatin. In addition, maltonis was able to induce: i) p21, p15 and Gadd45a mRNA upregulation; ii) Bcl-2, survivin, CDK6 and CDK8 down-regulation; iii) formation of γ-H2AX nuclear foci; iv) cleavage of PARP and Caspase 3. Two independent in vivo experiments demonstrated the tolerability and efficacy of maltonis in the inhibition of tumour growth. Finally maltonis was not extruded by ABCB1, one of the major determinants of chemotherapy failure, nor appeared to be a substrate of the glutathione-related detoxification system. CONCLUSIONS: Considering that treatment of poorly responsive patients still suffers for the paucity of agents able to revert chemoresistance, maltonis may be considered for the future development of new therapeutic approaches for refractory metastatic patients.

Preparation method and growth factor content of platelet concentrate influence the osteogenic differentiation of bone marrow stromal cells.

BACKGROUND AIMS: An extensive debate about the clinical benefits of autologous platelet concentrates used as a treatment option for patients with orthopedic injuries is ongoing. The aim of this study was to determine whether different compositions of platelet concentrates may affect the osteogenic differentiation of bone marrow stromal cells (BMSC). METHODS: Pure platelet-rich plasma (P-PRP) and leukocyte-PRP (L-PRP) were characterized for platelet and leukocyte content. As an indicative marker of the delivery of growth factors (GFs), the release of basic fibroblast growth factor (bFGF) from platelet gel (PG) was measured at 1, 18, 48 and 72 h and at 7 d. The ability of different PGs to induce proliferation and differentiation of BMSC was evaluated by using bioactivity assays. RESULTS: The platelet recovery was significantly higher in L-PRP, either fresh or frozen. PGs derived from L-PRP and P-PRP showed significant differences in terms of bFGF release and biological activity. bFGF release was faster both in fresh and frozen L-PRP preparations. Moreover, L-PRP samples were able to induce a significantly higher proliferation of BMSC compared with P-PRP or PPP samples. Even though all PG preparations allowed the deposition of mineral nodules in BMSC cultures, the mineralization activity correlated significantly with bFGF levels. CONCLUSIONS: The biological activity of platelet concentrates differs according to preparation technique, which affects platelet and leukocyte content and GF availability. Because GF levels are not always optimal in subjects with defective bone healing, composition and bioactivity of PRP should be analyzed to test the reliability and potential effectiveness of the regenerative treatment.

Bone Turnover Marker (BTM) Changes after Denosumab in Giant Cell Tumors of Bone (GCTB): A Phase II Trial Correlative Study.

Background: Giant cell tumors of bone (GCTB) are osteolytic tumors. Denosumab, a RANK-L inhibitor, is approved for GCTB. Data on serum bone turnover marker (sBTM) changes are lacking. We present a phase II correlative study on sBTMs in GCTB patients treated with denosumab. Methods: All GCTB patients receiving denosumab within a multicentre, open-label, phase 2 study were enrolled. Serum levels of carboxyterminal-crosslinked-telopeptide of type I collagen (s-CTX), alkaline phosphatase (ALP), bone-alkaline phosphatase (bALP), parathyroid hormone (sPTH), and osteocalcin (OCN) were prospectively assessed (baseline, T0, 3 months, T1, 6 months, T2). The primary endpoint was assessment of sBTM changes after denosumab; the secondary endpoints were disease-free survival (DFS) and sBTM correlation. Results: In 54 cases, sBTMs decreased during denosumab treatment except for sPTH. With a median follow-up of 59 months, 3-year DFS was 65% (%CI 52−79), with a significantly worse outcome for patients with high (≥500 UI/mL) s-CTX at baseline, as compared to low s-CTX (<500 UI/mL) (3-year DFS for high CTX 45% (95%CI 23−67) vs. 75% (95%CI 59−91) for low s-CTX. Higher median ALP and s-CTX were found for patients with tumor size ≥ 5 cm (p = 0.0512; p = 0.0589). Conclusion: Denosumab induces ALP/OCN and s-CTX reduction. High baseline s-CTX identifies a group of patients at higher risk of progression of the disease.

Chelation therapy and bone metabolism markers in thalassemia major.

The aim of our study was to investigate the effects of subcutaneous desferrioxamine (DFX) and oral deferiprone (L1) therapy on bone metabolism markers in patients with thalassemia major. We studied 17 patients with thalassemia receiving long-term treatment with desferrioxamine, 20 patients receiving long-term treatment with deferiprone, and 15 healthy age-matched controls. The following investigations were performed: a) intact parathyroid hormone (PTH), 25-hydroxyvitamin D [25(OH)D], 1,25-dihydroxyvitamin D [1,25(OH)2D] as endocrine parameters; b) alkaline phosphatase (ALP), bone alkaline phosphatase (BALP), osteocalcin (OC); c) bone resorption biochemical markers in serum and urine pyridinium crosslinks: hydroxylysyl-pyridinoline (HP) and lysyl-pyridinoline (LP); d) serum levels of cytokines and growth factors: transforming growth factor-beta1 (TGFbeta1), insulin-like growth factor-I (IGF-I), interleukin-1beta (IL-1beta), interleukin-6 (IL-6), tumor necrosis factor-a (TNFalpha); e) serum levels of IGF binding protein-3 (IGFBP-3). No significant differences among all studied variables were found in patients with thalassemia treated with desferrioxamine or deferiprone. In contrast, significant differences were found between patients with thalassemia and the control group: intact PTH was significantly lower in patients with thalassemia than in the controls (p < 0.0005), and a significant increase in ALP and BALP (p < 0.0005), but not in OC, was found in the patient group. With regard to bone resorption and remodeling markers, the urinary excretion of pyridinium crosslinks was higher in patients with thalassemia for HP fraction (p < 0.0005) and LP fraction (p = 0.002), as well as TGFbeta (p = 0.001). In contrast, IGF-I and IGFBP-3 were reduced when compared with controls. In conclusion, the study of bone metabolism markers in adult patients with thalassemia reveals a complex behavior with an increase in bone resorption indexes. Bone formation did not appear to be impaired. In particular, TGFbeta1 was higher in patients with thalassemia receiving L1 treatment.

Platelet-Rich Plasma: The Choice of Activation Method Affects the Release of Bioactive Molecules.

Platelet-Rich Plasma (PRP) is a low-cost procedure to deliver high concentrations of autologous growth factors (GFs). Platelet activation is a crucial step that might influence the availability of bioactive molecules and therefore tissue healing. Activation of PRP from ten voluntary healthy males was performed by adding 10% of CaCl2, 10% of autologous thrombin, 10% of a mixture of CaCl2 + thrombin, and 10% of collagen type I. Blood derivatives were incubated for 15 and 30 minutes and 1, 2, and 24 hours and samples were evaluated for the release of VEGF, TGF-ß1, PDGF-AB, IL-1ß, and TNF-α. PRP activated with CaCl2, thrombin, and CaCl2/thrombin formed clots detected from the 15-minute evaluation, whereas in collagen-type-I-activated samples no clot formation was noticed. Collagen type I produced an overall lower GF release. Thrombin, CaCl2/thrombin, and collagen type I activated PRPs showed an immediate release of PDGF and TGF-ß1 that remained stable over time, whereas VEGF showed an increasing trend from 15 minutes up to 24 hours. CaCl2 induced a progressive release of GFs from 15 minutes and increasing up to 24 hours. The method chosen to activate PRP influences both its physical form and the releasate in terms of GF amount and release kinetic.

Autophagy activation in COL6 myopathic patients by a low-protein-diet pilot trial.

A pilot clinical trial based on nutritional modulation was designed to assess the efficacy of a one-year low-protein diet in activating autophagy in skeletal muscle of patients affected by COL6/collagen VI-related myopathies. Ullrich congenital muscular dystrophy and Bethlem myopathy are rare inherited muscle disorders caused by mutations of COL6 genes and for which no cure is yet available. Studies in col6 null mice revealed that myofiber degeneration involves autophagy defects and that forced activation of autophagy results in the amelioration of muscle pathology. Seven adult patients affected by COL6 myopathies underwent a controlled low-protein diet for 12 mo and we evaluated the presence of autophagosomes and the mRNA and protein levels for BECN1/Beclin 1 and MAP1LC3B/LC3B in muscle biopsies and blood leukocytes. Safety measures were assessed, including muscle strength, motor and respiratory function, and metabolic parameters. After one y of low-protein diet, autophagic markers were increased in skeletal muscle and blood leukocytes of patients. The treatment was safe as shown by preservation of lean:fat percentage of body composition, muscle strength and function. Moreover, the decreased incidence of myofiber apoptosis indicated benefits in muscle homeostasis, and the metabolic changes pointed at improved mitochondrial function. These data provide evidence that a low-protein diet is able to activate autophagy and is safe and tolerable in patients with COL6 myopathies, pointing at autophagy activation as a potential target for therapeutic applications. In addition, our findings indicate that blood leukocytes are a promising noninvasive tool for monitoring autophagy activation in patients.

Chemotherapy-related toxicity in patients with non-metastatic Ewing sarcoma: influence of sex and age.

Influence of age and sex on chemotherapy-related toxicity was evaluated in children (3-9 years), adolescents (10-17 years), and adults (up to 40 years) with localized Ewing sarcoma (ES) enrolled in the ISG/SSG III protocol. Treatment was based on vincristine, doxorubicin, cyclophosphamide, ifosfamide, dactinomycin, and etoposide. High-dose chemotherapy with busulfan and melphalan was given in poor responder patients. The analysis was based on 2191 courses of standard chemotherapy and 230 patients. A lower risk of G4 leukopenia and thrombocytopenia, hospitalization, febrile neutropenia, and red blood cell (RBC) transfusions was observed in males. Use of granulocyte colony-stimulating factor (G-CSF) was more frequent in adults, while children more often received RBC transfusions. A significant correlation between sex and chemotherapy-related toxicity was observed in the study, whereas no significant differences in terms of bone marrow toxicity can be expected according to patient age. Further studies should analyse the role of pharmacokinetics, pharmacogenomics, and clinical characteristics.

Does platelet-rich plasma freeze-thawing influence growth factor release and their effects on chondrocytes and synoviocytes?

PRP cryopreservation remains a controversial point. Our purpose was to investigate the effect of freezing/thawing on PRP molecule release, and its effects on the metabolism of chondrocytes and synoviocytes. PRP was prepared from 10 volunteers, and a half volume underwent one freezing/thawing cycle. IL-1ß, HGF, PDGF AB/BB, TGF-ß1, and VEGF were assayed 1 hour and 7 days after activation. Culture media of chondrocytes and synoviocytes were supplemented with fresh or frozen PRP, and, at 7 days, proliferation, gene expression, and secreted proteins levels were evaluated. Results showed that in the freeze-thawed PRP the immediate and delayed molecule releases were similar or slightly lower than those in fresh PRP. TGF-ß1 and PDGF AB/BB concentrations were significantly reduced after freezing both at 1 hour and at 7 days, whereas HGF concentration was significantly lower in frozen PRP at 7 days. In fresh PRP IL-1ß and HGF concentrations underwent a significant further increase after 7 days. Similar gene expression was found in chondrocytes cultured with both PRPs, whereas in synoviocytes HGF gene expression was higher in frozen PRP. PRP cryopreservation is a safe procedure, which sufficiently preserves PRP quality and its ability to induce proliferation and the production of ECM components in chondrocytes and synoviocytes.

CD99 drives terminal differentiation of osteosarcoma cells by acting as a spatial regulator of ERK 1/2.

Differentiation therapy is an attractive treatment for osteosarcoma (OS). CD99 is a cell surface molecule expressed in mesenchymal stem cells and osteoblasts that is maintained during osteoblast differentiation while lost in OS. Herein, we show that whenever OS cells regain CD99, they become prone to reactivate the terminal differentiation program. In differentiating conditions, CD99-transfected OS cells express osteocyte markers, halt proliferation, and largely die by apoptosis, resembling the fate of mature osteoblasts. CD99 induces ERK activation, increasing its membrane-bound/cytoplasmic form rather than affecting its nuclear localization. Through cytoplasmic ERK, CD99 promotes activity of the main osteogenic transcriptional factors AP1 and RUNX2, which in turn enhance osteocalcin and p21(WAF1/CIP1) , leading to G0 /G1 arrest. These data underscore the alternative positions of active ERK into distinct subcellular compartments as key events for determining OS fate.

Serum levels of fibroblast growth factor 2 in children with orthopedic diseases: potential role in predicting bone healing.

Fibroblast growth factor 2 (FGF-2) plays an important role in the early phases of bone healing. In this study, we measured FGF-2 serum levels in 88 children undergoing surgical treatment for congenital (n = 49) or acquired (n = 39) orthopedic conditions, which were associated (n = 35) or not (n = 53) with bone lesions, to assess whether serum levels of FGF-2 varied according to the underlying disease and may predict clinical outcomes. FGF-2 serum levels were significantly lower in patients who did not heal after surgery (p = 0.008). Diagnostic accuracy was validated statistically, and the ROC curve provided a threshold value useful in discriminating good versus poor outcomes. The relationship between FGF-2 and bone healing was supported by in vitro experiments. A mineralization assay was performed on bone marrow stromal cells from three patients with congenital pseudarthrosis, who had low serum levels of FGF-2 and a poor clinical outcome after surgical treatment. Autologous serum alone was not sufficient to induce in vitro mineralization, but it did occur when cells were cultured with different sources of exogenous growth factors (GFs), including recombinant FGF-2 and homologous serum collected from children with fractures, high FGF-2 levels, and a good clinical outcome. In conclusion, our findings suggest that osteoinductive GFs are essential for bone repair, and that the amount of circulating FGF-2 may predict bone healing.

The relationship of vitamin D status to bone mineral density in an Italian population of postmenopausal women.

Several authors have found a relationship between vitamin D status and bone mineral density (BMD). To our knowledge, no previous studies on this topic have been carried out on the Italian postmenopausal population. We studied this relationship retrospectively in 156 Italian postmenopausal women. We also investigated the relationship between parathyroid hormone (PTH) and BMD. Measurements of BMD were taken at the lumbar spine and upper femur by dual X-ray absorptiometry. Serum 25(OH)D (calcidiol), 1,25(OH)2D (calcitriol), PTH, calcium, phosphorus, creatinine, osteocalcin and urinary calcium and phosphorus were measured according to the current laboratory methods of analysis. We found a positive statistically significant correlation between BMD, both at the spine and hip, and 25(OH)D, and a negative statistically significant correlation between BMD and PTH. No statistically significant correlation was found between BMD and 1,25(OH)2D. Crude logistic regression showed age, 25(OH)D and PTH were significant predictors of low BMD, while 1,25(OH)2D was not. Backward logistic regression showed 25(OH)D was the best predictive model for spine osteoporosis together with age, and on its own it was the best predictive model for femoral neck osteoporosis.