Soluble Hemojuvelin and Ferritin: Potential Prognostic Markers in Pediatric Hematopoietic Cell Transplantation.

OBJECTIVE: Iron overload (IO) is a common and life-threatening complication resulting from the therapy of AL and HCT patients. This study aimed to evaluate the prognostic value of 12 serum biomarkers of iron metabolism in pediatric patients treated for AL or undergoing HCT. PATIENTS: Overall, 50 patients with AL after intensive treatment and 32 patients after HCT were prospectively included in the study. AL patients at diagnosis and healthy controls served as reference groups. METHODS: The impact of the following 12 serum iron metabolism parameters on the outcome of AL/HCT patients was analyzed: iron, transferrin (Tf), total iron-binding capacity (TIBC), ferritin, ferritin heavy chains (FTH1), ferritin light chains (FTL), hepcidin, soluble hemojuvelin (sHJV), soluble ferroportin-1 (sFPN1), erythroferrone (ERFE), erythropoietin (EPO), and soluble transferrin receptor (sTfR). RESULTS: With a median follow-up of 2.2 years, high levels of ferritin and low levels of sHJV had an adverse prognostic impact on OS and EFS in children after HCT. If these patients were combined with those with AL after intensive chemotherapy, the results were confirmed for OS and EFS both for ferritin and sHJV. CONCLUSIONS: Among the 12 analyzed serum parameters of iron metabolism, increased levels of ferritin and decreased levels of sHJV had an adverse prognostic impact on survival in children after HCT. More data are needed to clarify the relationship between ferritin, sHJV, and mortality of AL children after intensive chemotherapy, and more extensive prospective studies are required to prove sHJV predictivity.

Bortezomib has little ex vivo activity in chronic myeloid leukemia: individual tumor response testing comparative study in acute and chronic myeloid leukemia.

AIM OF THE STUDY: Resistance to imatinib is one of the most important issues in treatment of chronic myeloid leukemia (CML) patients. The objective of the study was to analyze the ex vivo drug resistance profile to bortezomib and 22 other antileukemic drugs, including three tyrosine kinase inhibitors (TKIs), in CML in comparison to acute myeloid leukemia (AML). MATERIAL AND METHODS: A total of 82 patients entered the study, including 36 CML and 46 AML adults. Among CML patients, 19 had advanced disease, 16 were resistant to imatinib, and 6 had ABL-kinase domain mutations. The ex vivo drug resistance profile was studied by the MTT assay. RESULTS: CML CELLS WERE MORE RESISTANT THAN AML BLASTS TO THE FOLLOWING DRUGS: prednisolone, vincristine, doxorubicin, etoposide, melphalan, cytarabine, fludarabine, thiotepa, 4-HOO-cyclophosphamide, thioguanine, bortezomib, topotecan, and clofarabine. CML cells were 2-fold more sensitive to busulfan than AML cells. CML patients with clinical imatinib resistance had higher ex vivo resistance to vincristine, daunorubicin, etoposide, and busulfan. No significant differences to all tested drugs, including TKIs, were observed between CML patients with non-advanced and advanced disease. CML patients with mutation had higher ex vivo resistance to vincristine, idarubicin, thiotepa, and busulfan. CONCLUSIONS: CML cells are ex vivo more resistant to most drugs than acute myeloid leukemia blasts. Busulfan is more active in CML than AML cells. In comparison to AML cells, bortezomib has little ex vivo activity in CML cells. No differences between CML subgroups in sensitivity to 3 tested TKIs were detected.

Lymphocyte Subpopulations in Patients With Neurofibromatosis Type 1-associated Optic Pathway Gliomas and Plexiform Neurofibromas.

BACKGROUND/AIM: Neurofibromatosis type 1 (NF1) is characterized by the occurrence of multisystem tumors, among which the most characteristic are optic pathway gliomas (OPGs) and plexiform neurofibromas (PNFs). With the development of new anticancer drugs targeting the immune system, it is important to examine the immunological status of patients with NF1. Furthermore, the immune system has been suggested as a probable modulator of NF1-associated phenotypes. The objective of this study was the analysis of lymphocyte subset populations with respect to the presence of PNFs and OPGs. PATIENTS AND METHODS: Fifty-three patients with NF1 diagnosed with OPG/PNF were analyzed for lymphocyte subpopulations. RESULTS: Significantly lower levels of B-cells, T-cells and natural killer (NK) cells were observed in the group of patients with PNFs compared to those with OPG. CONCLUSION: Our observation may indicate a correlation between weakened functioning of the immune system and the formation of PNFs.

Outcome of Pediatric Acute Lymphoblastic Leukemia: Sixty Years of Progress.

BACKGROUND: A retrospective analysis was performed to investigate the survival outcomes in pediatric acute lymphoblastic leukemia (ALL) based on time period. We hypothesized that improvement has been obtained with the time-dependent therapeutic era and rise in the gross domestic product (GDP) and Human Development Index (HDI). MATERIALS AND METHODS: Data from 710 children who were treated for ALL between 1958 and 2018 at a single pediatric center were analyzed for probability of 5-year overall survival (pOS), event-free survival (pEFS) and relapse risk (pRR). Time periods were defined by the treatment protocols used in seven consecutive therapeutic eras. RESULTS: Over the 60-year period analyzed, pOS increased from 1.2% to 90.7%, pEFS from 1.2% to 86.6%, and pRR decreased from 98.8% to 9.9% for patients treated in the past decade. Risk of mortality for patients who received chemotherapy and hematopoietic cell transplant was reduced to 9.9% in the recent era, however, no statistically significant survival difference was found between patients treated with stem cell transplant and those not. CONCLUSION: The therapeutic era, related to improved GDP and HDI, was a statistically significant predictor of increased OS from ALL.

Prognostic impact of combined fludarabine, treosulfan and mitoxantrone resistance profile in childhood acute myeloid leukemia.

BACKGROUND: The role of cellular drug resistance in childhood acute myeloid leukemia (AML) has not yet been established. The aim of the study was the analysis of the clinical value of ex vivo drug resistance in pediatric AML. PATIENTS AND METHODS: A cohort of 90 children with de novo AML were assayed for drug resistance profile by the 3-4,5-dimethylthiazol-2-yl-2,5-difenyl tetrazolium bromide (MTT) assay and prognostic model of in vitro drug sensitivity was analyzed. RESULTS: Children who relapsed during follow-up showed higher in vitro resistance of leukemic blasts to most of the drugs tested, except for cytarabine, cladribine, vincristine, mercaptopurine and thioguanine. A combined in vitro drug resistance profile to fludarabine, treosulfan and mitoxantrone (FTM score) was defined and it had an independent prognostic significance for disease free survival in pediatric AML. CONCLUSION: The combined fludarabine, treosulfan and mitoxantrone resistance profile to possibly may be used for better stratification of children with AML or indicate the necessity for additional therapy.

Impact of CMV and EBV on Immune Recovery After Allogeneic Hematopoietic Cell Transplantation in Children.

BACKGROUND/AIM: Immune recovery is a key factor in the management of patients after allogeneic hematopoietic stem cell transplantation (allo-HSCT). This study analyzed the factors contributing to immune reconstitution after allo-HSCT. PATIENTS AND METHODS: Overall, 65 children with malignant or non-malignant diseases were included in multivariate analyses. RESULTS: The following factors contributed to a faster immune recovery: peripheral blood as a stem cell source and reactivation of CMV infection for CD3+ and CD4+ lymphocyte subpopulations; reactivation of CMV infection for CD8+ subset; donor EBV-IgG+ and no EBV reactivation for CD19 lymphocytes; recipient age below 10 years and peripheral blood as a stem cell source for NK cells. For CD2 and CD4/CD8 ratio no factor was significant in multivariate analysis. CONCLUSION: Patients receiving a graft from an EBV-IgG-positive donor and not having early EBV post-transplant viremia show faster recovery of the B-cells, while patients with early CMV-DNA-emia have a better re-establishment of T-cell subsets.

Predictive value of multidrug resistance proteins and cellular drug resistance in childhood relapsed acute lymphoblastic leukemia.

PURPOSE: Cellular resistance in childhood acute leukemias might be related to profile and function of multidrug resistance proteins and apoptosis regulating proteins. The aims of the study were: (1) analysis of expression of MRP1, PGP1, LRP, BCL-2 and p53 proteins; (2) correlation with ex vivo drug resistance, and (3) analysis of their prognostic impact on clinical outcome in childhood acute lymphoblastic (ALL) and acute myeloid (AML) leukemia. METHODS: Total number of 787 children diagnosed for initial ALL (n = 527), relapsed ALL (n = 104), initial AML (n = 133) and relapsed AML (n = 23) were included into the study. Mean follow-up period was 3.5 years. Drug resistance for up to 30 anticancer agents was performed by the MTT assay. Expression of all proteins was tested by flow cytometry. RESULTS: Both initial AML and relapsed ALL samples showed higher drug resistance than initial ALL samples. No significant differences were found in drug resistance between initial and relapsed AML samples. The presence of multidrug resistance and apoptosis proteins had no impact on pDFS in iALL and iAML, however strong trend towards adverse prognostic impact of MRP1, PGP and LRP on pDFS in rALL was observed. The same trend was observed for each of analyzed co-expressions of tested multidrug resistance proteins. CONCLUSIONS: The phenomenon of cellular drug resistance in childhood acute leukemias is multifactorial and plays an important role in response to therapy. Expression of MRP1, PGP and LRP proteins, as well as their co-expression play possible role in childhood relapsed ALL.

Activity of bortezomib in adult de novo and relapsed acute myeloid leukemia.

BACKGROUND: Bortezomib is an inhibitor of proteasome and NF-kappaB, with activity in various solid tumors and hematological malignancies. AIM: The aim of the study was the analysis of in vitro drug resistance to bortezomib and other anticancer drugs in de novo and relapsed adult acute myeloid leukemia (AML). PATIENTS AND METHODS: The leukemic cells of 46 adult patients with AML were tested for the in vitro drug resistance profile. The group included 20 de novo and 26 relapsed AML patients, among whom, 12 relapsed after allogeneic hematopoietic stem cell transplantation (HSCT) and 4 after autologous HSCT. The MTT assay was performed for 21 drugs. Expression of P-glycoprotein (PGP), multidrug resistance-associated protein-1 (MRP1) and lung resistance protein (LRP) proteins was measured by flow cytometry. RESULTS: No significant differences in drug resistance were found for all tested drugs between de novo and relapsed AML samples, while expression of PGP, MRP1 and LRP was higher in relapsed patients. Patients with refractory or relapsed disease, had higher resistance of myeloblasts to cyclophosphamide (RR = 2.4, p = 0.050), and better sensitivity to busulfan (RR = 0.4, p = 0.054) and topotecan (RR = 0.4, p = 0.031). Those who have died due to refractory/relapsed disease (n = 16) had better sensitivity to bortezomib (RR = 0.6, p = 0.046) and treosulfan (RR = 0.1, p = 0.018). CONCLUSION: In vitro drug resistance in relapsed adult AML is comparable to that in de novo disease. Activity in vitro of bortezomib might be a rationale for its use in refractory/relapsed AML adult patients.

Drug-resistance Profile in Multiple-relapsed Childhood Acute Lymphoblastic Leukemia.

AIM: To analyze the drug-resistance profile at first and subsequent relapse in children with acute lymphoblastic leukemia (ALL). PATIENTS AND METHODS: A total of 154 pediatric ALL samples were tested for ex vivo chemosensitivity for up to 19 drugs. Their combined drug resistance profile (PVA score) was analyzed. RESULTS: The median relative resistance scores between patients with multiple relapse and those with first relapse considering all drugs was 2.0. The median PVA score at subsequent relapses was 8 vs. 6 at first relapse (p=0.004). Samples from multiple-relapsed ALL were more drug resistant to: prednisolone (>1.9-fold), dexamethasone (>1.5-fold), vincristine (3.1-fold), L-asparaginase (5-fold), mitoxantrone (2.4-fold), cytarabine (4.3-fold), mercaptopurine (2.2-fold), thioguanine (4.8-fold), etoposide (2.6-fold) and melphalan (2.7-fold). Lymphoblasts at multiple relapse were comparably resistant to: daunorubicin, doxorubicin, cyclophosphamide, ifosfamide, busulfan, treosulfan, fludarabine, clofarabine and bortezomib. CONCLUSION: In comparison to first relapse, subsequent relapsed childhood ALL is more ex vivo-resistant to most tested drugs.

Phenotype of NK Cells Determined on the Basis of Selected Immunological Parameters in Children Treated due to Acute Lymphoblastic Leukemia.

Acute lymphoblastic leukemia (ALL) is the most frequent pediatric malignancy. The chemotherapy for ALL is associated with a profound secondary immune deficiency.We evaluated the number and phenotype of natural killer (NK) cells at diagnosis, after the intensive chemotherapy and following the completion of the entire treatment for patients with ALL. The fraction, absolute number, and percentage of NK cells expressing interferon-γ were determined in full blood samples. The fraction of NK cells expressing CD158a, CD158b, perforin, A, B, and K granzymes was examined in isolated NK cells.We have shown that patients assessed at ALL diagnosis showed significantly lower values of the fraction of NK cells and percentage of NK cells with the granzyme A expression. Additionally, the absolute number of NK cells, the expression of CD158a, CD158b, perforin, and granzyme A were significantly lower in patients who completed intensive chemotherapy. Also, there was a significantly higher fraction of NK cells expressing granzyme K in patients who completed the therapy.Abnormalities of NK cells were found at all stages of the treatment; however, the most pronounced changes were found at the end of intensive chemotherapy.

Individualized tumor response testing profile has a prognostic value in childhood acute leukemias: multicenter non-interventional long-term follow-up study.

A total number of 817 children with acute lymphoblastic leukemia (ALL) and 181 with acute myeloblastic leukemia (AML) were assessed for individualized tumor response testing (ITRT) profile as a prognostic factor in long-term follow-up. For each patient, ITRT, initial response to therapy and long-term outcome were assessed. In initial ALL, an impact on long-term response was shown in ITRT for 13 drugs, while in initial AML only for cytarabine. For patients with ALL, a combined five-drug ITRT profile for prednisolone, l-asparaginase, vincristine, cytarabine and daunorubicin or doxorubicin had predictive value for probability of disease-free survival (pDFS) in univariate analysis, whereas in multivariate analysis, bone marrow response by day 33 was the only prognostic factor. For patients with AML, no factor had prognostic value for pDFS in univariate analysis, while ITRT to cytarabine almost reached significance. In conclusion, ITRT can possibly be regarded as a risk factor in childhood acute leukemias.

Comparison of prognostic value of in vitro drug resistance and bone marrow residual disease on day 15 of therapy in childhood acute lymphoblastic leukemia.

AIM: The analysis of the prognostic impact of residual disease at day 15 of induction therapy, individual tumor response testing (ITRT) at diagnosis, initial factors and initial therapy response to the risk of relapse in children with precursor B-cell acute lymphoblastic leukemia (ALL). PATIENTS AND METHODS: A total of 87 children were tested at diagnosis for ITRT and for persistence of blasts in bone marrow at day 15 (BML15>0.5%) and were followed-up in long-term analysis. RESULTS: The probability of disease-free survival (pDFS) was significantly better for patients with an ITRT profile showing sensitivity to prednisolone, vincristine, daunorubicin, and L-asparaginase. Patients with BML15>0.5% had higher ITRT for prednisolone, daunorubicin, L-asparaginase, and etoposide. Three factors had predictive impact for relapse: BML15>0.5%, ITRT for prednisolone and high combined ITRT profile for prednisolone, vincristine and L-asparaginase (PVA score). CONCLUSION: Persistence of blasts in bone marrow at day 15, ITRT showing resistance to prednisolone and high PVA score were the strongest and comparable prognostic factors predicting relapse in childhood ALL.