Pharmacogenetics of the Primary and Metastatic Osteosarcoma: Gene Expression Profile Associated with Outcome.

Osteosarcoma (OS) is the most common malignant bone tumor in children and adolescents. In recent decades, OS treatment has reached a plateau and drug resistance is still a major challenge. Therefore, the present study aimed to analyze the expression of the genes related to pharmacogenetics in OS. The expression of 32 target genes in 80 paired specimens (pre-chemotherapeutic primary tumor, post-chemotherapeutic primary tumor and pulmonary metastasis) obtained from 33 patients diagnosed with OS were analyzed by the real-time PCR methodology. As the calibrators (control), five normal bone specimens were used. The present study identified associations between the OS outcome and the expression of the genes TOP2A, DHFR, MTHFR, BCL2L1, CASP3, FASLG, GSTM3, SOD1, ABCC1, ABCC2, ABCC3, ABCC5, ABCC6, ABCC10, ABCC11, ABCG2, RALBP1, SLC19A1, SLC22A1, ERCC1 and MSH2. In addition, the expression of the ABCC10, GGH, GSTM3 and SLC22A1 genes were associated with the disease event, and the metastasis specimens showed a high expression profile of ABCC1, ABCC3 and ABCC4 genes and a low expression of SLC22A1 and ABCC10 genes, which is possibly an important factor for resistance in OS metastasis. Therefore, our findings may, in the future, contribute to clinical management as prognostic factors as well as possible therapeutic targets.

Quantitative expression evaluation of PRAME gene in osteosarcoma.

BACKGROUND: In a previous study, our group observed that 68% of the osteosarcoma (OS) samples presented PRAME (Preferentially Expressed Antigen in Melanoma) gene expression. In this work, we propose to investigate quantitatively gene expression of PRAME in distinct patients groups. METHODS AND RESULTS: 61 osteosarcoma samples, from 3 distinct patients groups were selected for this study: (1) Patients younger than 10 years old at diagnosis, (2) Patients that had poor evolution of disease and (3) Patients that were in remission of disease and had treatment with no intercurrences) PRAME gene expression levels were obtained using quantitative Real-Time Polymerase Chain Reaction method (qRT-PCR). Clinical parameters were collected from patient's medical charts. Results demonstrated an increase in PRAME gene expression in all samples, with high variation in expression levels, when considering all samples and when analyzed in each group. In addition, no statistical difference was found when considering clinical data collected or patients groups. CONCLUSION: PRAME gene expression quantitative investigation did not bring any complementary information beyond of what had already been observed in other qualitative investigations published by our group, there is no relation between PRAME gene expression levels and disease evolution. However, the findings in this work contribute for validation PRAME gene expression as a good biomarker to OS, which, in the future, may allow identification circulating tumor cell or molecules to contribute with early diagnostic of metastasis, a genuine problem in OS that determinate flattening in survival curves.

ALVEOLAR RECRUITMENT MANEUVERS FOR CHILDREN WITH CANCER AND ACUTE RESPIRATORY DISTRESS SYNDROME: A FEASIBILITY STUDY.

OBJECTIVE: Acute respiratory distress syndrome (ARDS) can be a devastating condition in children with cancer and alveolar recruitment maneuvers (ARMs) can theoretically improve oxygenation and survival. The study aimed to assess the feasibility of ARMs in critically ill children with cancer and ARDS. METHODS: We retrospectively analyzed 31 maneuvers in a series of 12 patients (median age of 8.9 years) with solid tumors (n=4), lymphomas (n=2), acute lymphoblastic leukemia (n=2), and acute myeloid leukemia (n=4). Patients received positive end-expiratory pressure from 25 up to 40 cmH20, with a delta pressure of 15 cmH2O for 60 seconds. We assessed blood gases pre- and post-maneuvers, as well as ventilation parameters, vital signs, hemoglobin, clinical signs of pulmonary bleeding, and radiological signs of barotrauma. Pre- and post-values were compared by the Wilcoxon test. RESULTS: Median platelet count was 53,200/mm3. Post-maneuvers, mean arterial pressure decreased more than 20% in two patients, and four needed an increase in vasoactive drugs. Hemoglobin levels remained stable 24 hours after ARMs, and signs of pneumothorax, pneumomediastinum, or subcutaneous emphysema were absent. Fraction of inspired oxygen decreased significantly after ARMs (FiO2; p=0.003). Oxygen partial pressure (PaO2)/FiO2 ratio increased significantly (p=0.0002), and the oxygenation index was reduced (p=0.01), but all these improvements were transient. Recruited patients' 28-day mortality was 58%. CONCLUSIONS: ARMs, although feasible in the context of thrombocytopenia, lead only to transient improvements, and can cause significant hemodynamic instability.

Alveolar recruitment maneuvers for children with cancer and acute respiratory distress syndrome: a feasibility study / Manobras de recrutamento alveolar em crianças com câncer e síndrome do desconforto respiratório agudo: um estudo de viabilidade

ABSTRACT Objective: Acute respiratory distress syndrome (ARDS) can be a devastating condition in children with cancer and alveolar recruitment maneuvers (ARMs) can theoretically improve oxygenation and survival. The study aimed to assess the feasibility of ARMs in critically ill children with cancer and ARDS. Methods: We retrospectively analyzed 31 maneuvers in a series of 12 patients (median age of 8.9 years) with solid tumors (n=4), lymphomas (n=2), acute lymphoblastic leukemia (n=2), and acute myeloid leukemia (n=4). Patients received positive end-expiratory pressure from 25 up to 40 cmH20, with a delta pressure of 15 cmH2O for 60 seconds. We assessed blood gases pre- and post-maneuvers, as well as ventilation parameters, vital signs, hemoglobin, clinical signs of pulmonary bleeding, and radiological signs of barotrauma. Pre- and post-values were compared by the Wilcoxon test. Results: Median platelet count was 53,200/mm3. Post-maneuvers, mean arterial pressure decreased more than 20% in two patients, and four needed an increase in vasoactive drugs. Hemoglobin levels remained stable 24 hours after ARMs, and signs of pneumothorax, pneumomediastinum, or subcutaneous emphysema were absent. Fraction of inspired oxygen decreased significantly after ARMs (FiO2; p=0.003). Oxygen partial pressure (PaO2)/FiO2 ratio increased significantly (p=0.0002), and the oxygenation index was reduced (p=0.01), but all these improvements were transient. Recruited patients' 28-day mortality was 58%. Conclusions: ARMs, although feasible in the context of thrombocytopenia, lead only to transient improvements, and can cause significant hemodynamic instability.

RESUMO Objetivo: A síndrome do desconforto respiratório agudo (SDRA) pode ser uma condição devastadora em crianças com câncer e as manobras de recrutamento alveolar (MRA) podem melhorar a oxigenação e a sobrevida. O objetivo foi avaliar a viabilidade das MRA em crianças gravemente doentes com câncer e SDRA. Métodos: Analisamos retrospectivamente 31 manobras em 12 pacientes (idade mediana de 8,9 anos), com tumores sólidos (n=4), linfomas (n=2) e leucemias linfoide (n=2) e mieloide agudas (n=4). Os pacientes receberam pressão expiratória final positiva de 25 a 40 cmH20, com delta de pressão de 15 cmH2O por 60 segundos. Gasometrias foram analisadas pré e pós-manobras, bem como os parâmetros de ventilação, sinais vitais, hemoglobina, sinais clínicos de sangramento pulmonar e sinais radiológicos de barotrauma. Valores foram comparados com o teste de Wilcoxon. Resultados: A contagem mediana de plaquetas era de 53.200/mm3. Após as manobras, em dois pacientes, a pressão arterial média declinou mais de 20%, e quatro necessitaram de aumento de drogas vasoativas. A hemoglobina permaneceu estável 24 horas após a MRA, sem sinais de pneumotórax, pneumomediastino ou enfisema subcutâneo. Houve diminuição significativa nas frações inspiradas de oxigênio (FiO2; p=0,003). A relação pressão arterial de oxigênio (PaO2)/FiO2 aumentou (p=0,002), e o índice de oxigenação caiu (p=0,01), mas essas melhoras foram transitórias. A mortalidade em 28 dias foi de 58%. Conclusões: As MRA, embora viáveis no contexto da trombocitopenia, levam apenas a melhorias transitórias e podem causar instabilidade hemodinâmica significativa.

Invasive pneumococcal disease in children with cancer: Incidence density, risk factors and isolated serotypes

ABSTRACT Background: Pediatric oncology patients (POP) have a high risk of infections due to impaired immunity. Invasive pneumococcal disease (IPD) is an important cause of severe infection in these patients and it is associated with high mortality. This study aimed to evaluate the incidence and risk factors associated with IPD at a Pediatric Oncology Center in Brazil. Methods: This was a retrospective case-control study. All IPD cases in children with cancer from 2005 through 2016 were reviewed. Each case of IPD was matched with two controls from a cohort of patients matched for year of IPD, age and disease in order to assess risk factors. The incidence density was calculated as the number of IPD per 100,000 patients-year. Results: A total of 51 episodes of IPD in 49 patients was identified. All pneumococci were isolated from blood cultures. The median age was five years and 67% were male; mortality rate was 7.8%. The IPD incidence density rate in POP was 311.21 per 100,000 patients-year, significantly higher than the rate in the general pediatric population. Severe neutropenia was the only risk factor associated with IPD, after multivariate conditional logistic regression analysis. Conclusion: Although pneumococcal disease decreased after the introduction of 10-valent pneumococcal vaccine in the Brazilian national immunization schedule in 2010, there was no decrease in the IPD incidence rate in our cohort. A higher coverage rate of pneumococcal vaccination in children in the general population might be necessary to reduce the incidence rate in this high-risk population.

Invasive pneumococcal disease in children with cancer: Incidence density, risk factors and isolated serotypes.

BACKGROUND: Pediatric oncology patients (POP) have a high risk of infections due to impaired immunity. Invasive pneumococcal disease (IPD) is an important cause of severe infection in these patients and it is associated with high mortality. This study aimed to evaluate the incidence and risk factors associated with IPD at a Pediatric Oncology Center in Brazil. METHODS: This was a retrospective case-control study. All IPD cases in children with cancer from 2005 through 2016 were reviewed. Each case of IPD was matched with two controls from a cohort of patients matched for year of IPD, age and disease in order to assess risk factors. The incidence density was calculated as the number of IPD per 100,000 patients-year. RESULTS: A total of 51 episodes of IPD in 49 patients was identified. All pneumococci were isolated from blood cultures. The median age was five years and 67% were male; mortality rate was 7.8%. The IPD incidence density rate in POP was 311.21 per 100,000 patients-year, significantly higher than the rate in the general pediatric population. Severe neutropenia was the only risk factor associated with IPD, after multivariate conditional logistic regression analysis. CONCLUSION: Although pneumococcal disease decreased after the introduction of 10-valent pneumococcal vaccine in the Brazilian national immunization schedule in 2010, there was no decrease in the IPD incidence rate in our cohort. A higher coverage rate of pneumococcal vaccination in children in the general population might be necessary to reduce the incidence rate in this high-risk population.

Candida spp bloodstream infections in a Latin American Pediatric Oncology Reference Center: Epidemiology and associated factors.

BACKGROUND: Invasive fungal disease is a significant cause of morbidity and mortality in immunosuppressed children. The recognition of patients at risk for candidaemia is paramount to a better prognosis. OBJECTIVES: To characterize Candida spp bloodstream infections (BSI) in a reference centre for paediatric oncology and to describe the most prevalent risk factors associated with candida infections. PATIENTS/METHODS: This is a retrospective cohort study carried out with paediatric patients followed up with at the Institute of Pediatric Oncology, Brazil, who presented positive blood culture for Candida spp from January 2004 to December 2016. RESULTS: Ninety episodes of candidaemia were analysed; patients had a median age of 4.5 years, and 57.8% were males, with a diagnosis of solid tumours in 54.5% of cases. The most common Candida species were C albicans (35.6%), C parapsilosis (30.0%) and C tropicalis (16.7%). C tropicalis BSI was associated with neutropenia and skin lesions. Therapy was successful in 67.1% of the episodes. Older age and thrombocytopenia were associated with therapeutic failure. Death within 30 days occurred in 24.4% of patients; predictive factors were older age and admission to an ICU C parapsilosis candidaemia was a protective factor for death when compared to C albicans. CONCLUSION: The main species isolated were C albicans, C parapsilosis and C tropicalis. C tropicalis BSI was associated with neutropenia and skin lesions. The death rate was significant, and a worse prognosis was associated with older age, thrombocytopenia and admission to an ICU C parapsilosis infection proved to be a protective factor against mortality.

MAPK7 variants related to prognosis and chemotherapy response in osteosarcoma.

Osteosarcoma (OS) is a class of cancer originating from the bone, affecting mainly children and young adults. Our previous study showed that MAPK7 gene overexpression was significantly associated with tumor progression, poor treatment response, and worse overall survival, suggesting that MAPK7 could play an important role in OS tumorigenesis. We have investigated if MAPK7 overexpression was a result of any genomic changes in OS tumor specimens. We identified five SNPs (Single Nucleotide Polymorphism) previously described in databases, dbSNP and COSMIC, and identified two single nucleotide substitution not yet described. We found, in prechemotherapy specimens, a significant association of MAPK7 rs2233072G allele variant with metastasis at diagnosis and relapse (0.0909 and 0.0455, respectively). In post-chemotherapy, rs1054206GG specimen's genotype was associated with osteoblastic histological type (P= 0.0249) and presented decreased MAPK7 gene expression when compared with pre-chemotherapy specimens of same patients (P = 0.0095). Interestingly, it was observed some SNPs genotype exchange after chemotherapy. Our data indicated that MAPK7 gene expression associated with genotype exchange after chemotherapy, and these SNPs associated with important clinical parameters might be a valuable indicator for predicting in OS.

New therapeutic target for pediatric anaplastic ependymoma control: study of anti-tumor activity by a Kunitz-type molecule, Amblyomin-X.

EPNs comprise a heterogeneous group of neuroepithelial tumors, accounting for about 10% of all intracranial tumors in children and up to 30% of brain tumors in those younger than 3 years. Actually, the pattern therapy for low-grade EPNs includes complete surgical resection followed by radiation therapy. Total surgical excision is often not possible due to tumor location. The aim of this study was to evaluate, for the first time, the anti-tumor activity of Amblyomin-X in 4 primary cultures derived from pediatric anaplastic posterior fossa EPN, Group A (anaplastic, WHO grade III) and one primary culture of a high grade neuroepithelial tumor with MN1 alteration, which was initially misdiagnosed as EPN: i) by in vitro assays: comparisons of temozolomide and cisplatin; ii) by intracranial xenograft model. Amblyomin-X was able to induce cell death in EPN cells in a more significant percentage compared to cisplatin. The cytotoxic effects of Amblyomin-X were not detected on hFSCs used as control, as opposed to cisplatin-treatment, which promoted a substantial effect in the hAFSCs viability. TEM analysis showed ultrastructural alterations related to the process of cell death: mitochondrial degeneration, autophagosomes and aggregate-like structures. MRI and histopathological analyzes demonstrated significant tumor mass regression. Our results suggest that Amblyomin-X has a selective effect on tumor cells by inducing apoptotic cell death and may be a therapeutic option for Group AEPNs.

A pharmacokinetic model for voriconazole in a highly diversified population of children and adolescents with cancer.

BACKGROUND: The wide pharmacokinetic variability of voriconazole leads to uncertainty regarding adequate exposure. OBJECTIVES: To create a pharmacokinetic model that could help to explain the variability. METHODS: Retrospective review of paediatric patients with cancer. Models were built using Pmetrics. RESULTS: We analysed 158 trough measurements in 55 patients; in 41.8%, the serum levels were between 1 and 6 mg/L on initial measurement. After the measurements, dosage adjustments were made in 42 (76.3%) patients, and the percentage of adequate levels rose to 54.5%. Fourteen deaths (25.4%) were attributed to invasive fungal diseases. The mean serum levels were higher in deceased patients (mean ± SD: 3.1 ± 3.2 mg/L vs 2.5 ± 3.6 mg/L in survivors; P = 0.018), but the median doses per kg were higher in survivors. Drug exposure was also higher in deceased patients (mean ± SD of AUC: 19.2 ± 8.1 vs 9.5 ± 19.1 in survivors; P = 0.005). No correlation was found between serum concentrations <1 mg/L and death attributable to fungal disease. Bioavailability was estimated in 50%. The maximum velocity of clearance was reduced in deceased patients. CONCLUSIONS: Extremely ill patients can be poor metabolizers of voriconazole. Therapeutic monitoring promotes only a limited improvement in drug management.

New therapeutic target for pediatric anaplastic ependymoma control: study of anti-tumor activity by a Kunitz-type molecule, Amblyomin-X

EPNs comprise a heterogeneous group of neuroepithelial tumors, accounting for about 10% of all intracranial tumors in children and up to 30% of brain tumors in those younger than 3 years. Actually, the pattern therapy for low-grade EPNs includes complete surgical resection followed by radiation therapy. Total surgical excision is often not possible due to tumor location. The aim of this study was to evaluate, for the first time, the anti-tumor activity of Amblyomin-X in 4 primary cultures derived from pediatric anaplastic posterior fossa EPN, Group A (anaplastic, WHO grade III) and one primary culture of a high grade neuroepithelial tumor with MN1 alteration, which was initially misdiagnosed as EPN: i) by in vitro assays: comparisons of temozolomide and cisplatin; ii) by intracranial xenograft model. Amblyomin-X was able to induce cell death in EPN cells in a more significant percentage compared to cisplatin. The cytotoxic effects of Amblyomin-X were not detected on hFSCs used as control, as opposed to cisplatin-treatment, which promoted a substantial effect in the hAFSCs viability. TEM analysis showed ultrastructural alterations related to the process of cell death: mitochondrial degeneration, autophagosomes and aggregate-like structures. MRI and histopathological analyzes demonstrated significant tumor mass regression. Our results suggest that Amblyomin-X has a selective effect on tumor cells by inducing apoptotic cell death and may be a therapeutic option for Group AEPNs.

New therapeutic target for pediatric anaplastic ependymoma control: study of anti-tumor activity by a Kunitz-type molecule, Amblyomin-X

EPNs comprise a heterogeneous group of neuroepithelial tumors, accounting for about 10% of all intracranial tumors in children and up to 30% of brain tumors in those younger than 3 years. Actually, the pattern therapy for low-grade EPNs includes complete surgical resection followed by radiation therapy. Total surgical excision is often not possible due to tumor location. The aim of this study was to evaluate, for the first time, the anti-tumor activity of Amblyomin-X in 4 primary cultures derived from pediatric anaplastic posterior fossa EPN, Group A (anaplastic, WHO grade III) and one primary culture of a high grade neuroepithelial tumor with MN1 alteration, which was initially misdiagnosed as EPN: i) by in vitro assays: comparisons of temozolomide and cisplatin; ii) by intracranial xenograft model. Amblyomin-X was able to induce cell death in EPN cells in a more significant percentage compared to cisplatin. The cytotoxic effects of Amblyomin-X were not detected on hFSCs used as control, as opposed to cisplatin-treatment, which promoted a substantial effect in the hAFSCs viability. TEM analysis showed ultrastructural alterations related to the process of cell death: mitochondrial degeneration, autophagosomes and aggregate-like structures. MRI and histopathological analyzes demonstrated significant tumor mass regression. Our results suggest that Amblyomin-X has a selective effect on tumor cells by inducing apoptotic cell death and may be a therapeutic option for Group AEPNs.

The influence of cell concentration at cryopreservation on neutrophil engraftment after autologous peripheral blood stem cell transplantation

ABSTRACT Background: Peripheral blood stem cell concentrations are traditionally adjusted to 20-40 × 106 leukocytes/mL prior to freezing. This low cell concentration at cryopreservation implies larger volumes with more dimethyl sulfoxide being used, and higher cost and toxicity at the time of transplant. Higher cell concentrations have been reported but this is not widely accepted. Moreover, the influence of cell concentration on engraftment has not been well documented. Therefore, this study retrospectively analyzed the influence of peripheral blood stem cell concentration at freezing on engraftment after autologous hematopoietic stem cell transplantation. Method: Leukapheresis products were plasma-depleted and cryopreserved with 5% dimethyl sulfoxide, 6% hydroxyethylamide solution and 4% albumin in a −80 °C freezer. Individual patient data from hospital records were reviewed. Results: Fifty consecutive patients with oncological diseases underwent 88 leukaphereses. Median age was six years (range: 1-32 years) and median weight was 19 kg (range: 8-94 kg). Median leukocyte concentration was 109 × 106/mL at collection and 359 × 106 (range: 58-676 × 106) at freezing with 78% viability (range: 53-95%); leukocyte recovery after thawing was 95% (range: 70-100%). In multivariate analysis, cell concentration (p-value = 0.001) had a negative impact on engraftment. Patients infused with bags frozen with <200 × 106 leukocytes/mL engrafted after a median of nine days (range: 8-12 days), 200-400 × 106 leukocytes/mL after 11 days (range: 9-20 days); 400-600 × 106 leukocytes/mL after 12 days (range: 8-19 days) and with cell concentrations >600 × 106 leukocytes/mL, engraftment was after 14 days (range: 13-22 days). Conclusion: In patients with adequate CD34 cell collections, total leukocyte concentrations of 282 × 106/mL, freezing with 5% dimethyl sulfoxide and 6% hydroxyethylamide solution without a controlled-rate freezer, and storing cells at −80 ºC yielded excellent engraftment. Further increases in cell concentration may delay engraftment, without affecting safety.

The influence of cell concentration at cryopreservation on neutrophil engraftment after autologous peripheral blood stem cell transplantation.

BACKGROUND: Peripheral blood stem cell concentrations are traditionally adjusted to 20-40 × 106 leukocytes/mL prior to freezing. This low cell concentration at cryopreservation implies larger volumes with more dimethyl sulfoxide being used, and higher cost and toxicity at the time of transplant. Higher cell concentrations have been reported but this is not widely accepted. Moreover, the influence of cell concentration on engraftment has not been well documented. Therefore, this study retrospectively analyzed the influence of peripheral blood stem cell concentration at freezing on engraftment after autologous hematopoietic stem cell transplantation. METHOD: Leukapheresis products were plasma-depleted and cryopreserved with 5% dimethyl sulfoxide, 6% hydroxyethylamide solution and 4% albumin in a -80 °C freezer. Individual patient data from hospital records were reviewed. RESULTS: Fifty consecutive patients with oncological diseases underwent 88 leukaphereses. Median age was six years (range: 1-32 years) and median weight was 19 kg (range: 8-94 kg). Median leukocyte concentration was 109 × 106/mL at collection and 359 × 106 (range: 58-676 × 106) at freezing with 78% viability (range: 53-95%); leukocyte recovery after thawing was 95% (range: 70-100%). In multivariate analysis, cell concentration (p-value = 0.001) had a negative impact on engraftment. Patients infused with bags frozen with <200 × 106 leukocytes/mL engrafted after a median of nine days (range: 8-12 days), 200-400 × 106 leukocytes/mL after 11 days (range: 9-20 days); 400-600 × 106 leukocytes/mL after 12 days (range: 8-19 days) and with cell concentrations >600 × 106 leukocytes/mL, engraftment was after 14 days (range: 13-22 days). CONCLUSION: In patients with adequate CD34 cell collections, total leukocyte concentrations of 282 × 106/mL, freezing with 5% dimethyl sulfoxide and 6% hydroxyethylamide solution without a controlled-rate freezer, and storing cells at -80 °C yielded excellent engraftment. Further increases in cell concentration may delay engraftment, without affecting safety.

Establishment of primary cell culture and an intracranial xenograft model of pediatric ependymoma: a prospect for therapy development and understanding of tumor biology.

BACKGROUND: Ependymoma (EPN), the third most common pediatric brain tumor, is a central nervous system (CNS) malignancy originating from the walls of the ventricular system. Surgical resection followed by radiation therapy has been the primary treatment for most pediatric intracranial EPNs. Despite numerous studies into the prognostic value of histological classification, the extent of surgical resection and adjuvant radiotherapy, there have been relatively few studies into the molecular and cellular biology of EPNs. RESULTS: We elucidated the ultrastructure of the cultured EPN cells and characterized their profile of immunophenotypic pluripotency markers (CD133, CD90, SSEA-3, CXCR4). We established an experimental EPN model by the intracerebroventricular infusion of EPN cells labeled with multimodal iron oxide nanoparticles (MION), thereby generating a tumor and providing a clinically relevant animal model. MRI analysis was shown to be a valuable tool when combined with effective MION labeling techniques to accompany EPN growth. CONCLUSIONS: We demonstrated that GFAP/CD133+CD90+/CD44+ EPN cells maintained key histopathological and growth characteristics of the original patient tumor. The characterization of EPN cells and the experimental model could facilitate biological studies and preclinical drug screening for pediatric EPNs. METHODS: In this work, we established notoriously challenging primary cell culture of anaplastic EPNs (WHO grade III) localized in the posterior fossa (PF), using EPNs obtained from 1 to 10-year-old patients (n = 07), and then characterized their immunophenotype and ultrastructure to finally develop a xenograft model.

Establishment of primary cell culture and an intracranial xenograft model of pediatric ependymoma: a prospect for therapy development and understanding of tumor biology

Background: Ependymoma (EPN), the third most common pediatric brain tumor, is a central nervous system (CNS) malignancy originating from the walls of the ventricular system. Surgical resection followed by radiation therapy has been the primary treatment for most pediatric intracranial EPNs. Despite numerous studies into the prognostic value of histological classification, the extent of surgical resection and adjuvant radiotherapy, there have been relatively few studies into the molecular and cellular biology of EPNs. Results: We elucidated the ultrastructure of the cultured EPN cells and characterized their profile of immunophenotypic pluripotency markers (CD133, CD90, SSEA-3, CXCR4). We established an experimental EPN model by the intracerebroventricular infusion of EPN cells labeled with multimodal iron oxide nanoparticles (MION), thereby generating a tumor and providing a clinically relevant animal model. MRI analysis was shown to be a valuable tool when combined with effective MION labeling techniques to accompany EPN growth. Conclusions: We demonstrated that GFAP/CD133+CD90+/CD44+ EPN cells maintained key histopathological and growth characteristics of the original patient tumor. The characterization of EPN cells and the experimental model could facilitate biological studies and preclinical drug screening for pediatric EPNs. Methods: In this work, we established notoriously challenging primary cell culture of anaplastic EPNs (WHO grade III) localized in the posterior fossa (PF), using EPNs obtained from 1 to 10-year-old patients (n = 07), and then characterized their immunophenotype and ultrastructure to finally develop a xenograft model.

Establishment of primary cell culture and an intracranial xenograft model of pediatric ependymoma: a prospect for therapy development and understanding of tumor biology

Background: Ependymoma (EPN), the third most common pediatric brain tumor, is a central nervous system (CNS) malignancy originating from the walls of the ventricular system. Surgical resection followed by radiation therapy has been the primary treatment for most pediatric intracranial EPNs. Despite numerous studies into the prognostic value of histological classification, the extent of surgical resection and adjuvant radiotherapy, there have been relatively few studies into the molecular and cellular biology of EPNs. Results: We elucidated the ultrastructure of the cultured EPN cells and characterized their profile of immunophenotypic pluripotency markers (CD133, CD90, SSEA-3, CXCR4). We established an experimental EPN model by the intracerebroventricular infusion of EPN cells labeled with multimodal iron oxide nanoparticles (MION), thereby generating a tumor and providing a clinically relevant animal model. MRI analysis was shown to be a valuable tool when combined with effective MION labeling techniques to accompany EPN growth. Conclusions: We demonstrated that GFAP/CD133+CD90+/CD44+ EPN cells maintained key histopathological and growth characteristics of the original patient tumor. The characterization of EPN cells and the experimental model could facilitate biological studies and preclinical drug screening for pediatric EPNs. Methods: In this work, we established notoriously challenging primary cell culture of anaplastic EPNs (WHO grade III) localized in the posterior fossa (PF), using EPNs obtained from 1 to 10-year-old patients (n = 07), and then characterized their immunophenotype and ultrastructure to finally develop a xenograft model.

Cytokine Kinetics in Febrile Neutropenic Children: Insights on the Usefulness as Sepsis Biomarkers, Influence of Filgrastim, and Behavior of the IL-23/IL-17 Pathway.

BACKGROUND: The study aimed to describe the kinetics of various cytokines from day 1 to day 14 of the onset of fever in neutropenic children and to evaluate their performances as discriminators of sepsis in the first 24 hours of fever, the possible influence of filgrastim, and the functioning of the IL-23/IL-17 axis. METHODS: IL-1ß, TNF-α, IL-10, IL-12/23p40, IL-21, IL-6, IL-8, IL-17, G-CSF, and GM-CSF were measured in plasma on days 1, 2, 3, 5, and 14 from the onset of fever in 35 patients. RESULTS: Thirteen patients (37.1%) developed sepsis. In mixed models, IL-6, IL-8, IL-10, and G-CSF showed higher estimated means in septic patients (P < 0.005), and IL-12/23p40 and IL-17 in nonseptic patients (P < 0.05). On day 1, IL-6, IL-8, and IL-10 appeared upregulated in patients who received filgrastim. Only IL-6, IL-8, IL-10, and procalcitonin were useful as discriminators of sepsis. Associating the markers with each other or to a risk assessment model improved performance. CONCLUSIONS: Cytokines kinetics showed proinflammatory and anti-inflammatory responses similar to what is described in nonneutropenic patients. IL-8, IL-6, IL-10, and procalcitonin are useful as early biomarkers of sepsis. Filgrastim upregulates expression of these markers, and we observed deficiency in the IL-23-IL-17 axis accompanying sepsis.