Long-term outcome of children with acute promyelocytic leukemia: a randomized study of oral versus intravenous arsenic by SCCLG-APL group.

Realgar-Indigo naturalis formula (RIF), an oral traditional Chinese medicine mainly containing Realgar (As4S4), is highly effective in treating adult acute promyelocytic leukemia (APL). However, the treatment efficacy and safety of RIF have not been verified in pediatric patients. SCCLG-APL group conducted a multicenter randomized non-inferiority trial to determine whether intravenous arsenic trioxide (ATO) can be substituted by oral RIF in treating pediatric APL. Of 176 eligible patients enrolled, 91 and 85 were randomized to ATO and RIF groups, respectively. Patients were treated with the risk-adapted protocol. Induction, consolidation, and 96-week maintenance treatment contained all-trans-retinoic acid and low-intensity chemotherapy, and either ATO or RIF. The primary endpoint was 5-year event-free survival (EFS). The secondary endpoints were adverse events and hospital days. After a median 6-year follow-up, the 5-year EFS was 97.6% in both groups. However, the RIF group had significantly shorter hospital stays and lower incidence of infection and tended to have less cardiac toxicity. All 4 relapses occurred within 1.5 years after completion of maintenance therapy. No long-term arsenic retentions were observed in either group. Substituting oral RIF for ATO maintains treatment efficacy while reducing hospitalization and adverse events in treating pediatric APL patients, which may be a future treatment strategy for APL.

[Blinatumomab as bridging therapy in two children with B-cell acute lymphoblastic leukemia complicated by invasive fungal disease]. / 2例急性Bæ·‹å·´ç»†èƒžç™½è¡€ç— åˆå¹¶ä¾µè¢­æ€§çœŸèŒç— å„¿ç«¥åº”ç”¨è´æž—å¦¥æ¬§å•æŠ—æ¡¥æŽ¥æ²»ç–—åˆ†æž.

This article reports two cases of children with B-cell acute lymphoblastic leukemia (B-ALL) complicated by invasive fungal disease (IFD) who received bridging treatment using blinatumomab. Case 1 was a 4-month-old female infant who experienced recurrent high fever and limb weakness during chemotherapy. Blood culture was negative, and next-generation sequencing (NGS) of peripheral blood, bronchoalveolar lavage fluid, and cerebrospinal fluid were all negative. Chest CT and cranial MRI revealed obvious infection foci. Case 2 was a 2-year-old male patient who experienced recurrent high fever with multiple inflammatory masses during chemotherapy. Candida tropicalis was detected in peripheral blood and abscess fluid using NGS, while blood culture and imaging examinations showed no obvious abnormalities. After antifungal and blinatumomab therapy, both cases showed significant improvement in symptoms, signs, and imaging, and B-ALL remained in continuous remission. The report indicates that bridging treatment with blinatumomab in children with B-ALL complicated by IFD can rebuild the immune system and control the underlying disease in the presence of immunosuppression and severe fungal infection.

Differentiation syndrome and coagulation disorder - comparison between treatment with oral and intravenous arsenics in pediatric acute promyelocytic leukemia.

Realgar-Indigo naturalis formula (RIF), with A4S4 as a major ingredient, is an oral arsenic used in China to treat pediatric acute promyelocytic leukemia (APL). The efficacy of RIF is similar to that of arsenic trioxide (ATO). However, the effects of these two arsenicals on differentiation syndrome (DS) and coagulation disorders, the two main life-threatening events in children with APL, remain unclear. We retrospectively analyzed 68 consecutive children with APL from South China Children Leukemia Group-APL (SCCLG-APL) study. Patients received all-trans retinoic acid (ATRA) on day 1 of induction therapy. ATO 0.16 mg/kg day or RIF 135 mg/kg·day was administrated on day 5, while mitoxantrone was administered on day 3 (non-high-risk) or days 2-4 (high-risk). The incidences of DS were 3.0% and 5.7% in ATO (n = 33) and RIF (n = 35) arms (p = 0.590), and 10.3% and 0% in patients with and without differentiation-related hyperleukocytosis (p = 0.04), respectively. Moreover, in patients with differentiation-related hyperleukocytosis, the incidence of DS was not significantly different between ATO and RIF arms. The dynamic changes of leukocyte count between arms were not statistically different. However, patients with leukocyte count > 2.61 × 109/L or percentage of promyelocytes in peripheral blood > 26.5% tended to develop hyperleukocytosis. The improvement of coagulation indexes in ATO and RIF arms was similar, with fibrinogen and prothrombin time having the quickest recovery rate. This study showed that the incidence of DS and recovery of coagulopathy are similar when treating pediatric APL with RIF or ATO.

[Recent research on cognitive impairment in children with acute lymphoblastic leukemia]. / æ€¥æ€§æ·‹å·´ç»†èƒžç™½è¡€ç— å„¿ç«¥è®¤çŸ¥åŠŸèƒ½æŸå®³çš„ä¸´åºŠç ”ç©¶è¿›å±•.

Acute lymphoblastic leukemia (ALL) is the most common malignant neoplastic disease in children. With the continuous improvement in diagnosis and treatment, there has been an increasing number of ALL children who achieve long-term survival after complete remission; however, a considerable proportion of these children have cognitive impairment, which has a serious adverse impact on their learning, employment, and social life. This article reviews the latest research on cognitive impairment in children with ALL from the aspects of the influencing factors, detection techniques, and prevention/treatment methods for cognitive impairment.

Prognostic significance of CNSL at diagnosis of childhood B-cell acute lymphoblastic leukemia: A report from the South China Children's Leukemia Group.

Objectives: The prognostic significance of acute lymphoblastic leukemia (ALL) patients with central nervous system leukemia (CNSL) at diagnosis is controversial. We aimed to determine the impact of CNSL at diagnosis on the clinical outcomes of childhood B-cell ALL in the South China Children's Leukemia Group (SCCLG). Methods: A total of 1,872 childhood patients were recruited for the study between October 2016 and July 2021. The diagnosis of CNSL depends on primary cytological examination of cerebrospinal fluid, clinical manifestations, and imaging manifestations. Patients with CNSL at diagnosis received two additional courses of intrathecal triple injections during induction. Results: The frequency of CNLS at the diagnosis of B-cell ALL was 3.6%. Patients with CNSL at diagnosis had a significantly higher mean presenting leukocyte count (P = 0.002) and poorer treatment response (P <0.05) compared with non-CNSL patients. Moreover, CNSL status was associated with worse 3-year event-free survival (P = 0.030) and a higher risk of 3-year cumulative incidence of relapse (P = 0.008), while no impact was observed on 3-year overall survival (P = 0.837). Multivariate analysis revealed that CNSL status at diagnosis was an independent predictor with a higher cumulative incidence of relapse (hazard ratio = 2.809, P = 0.016). Conclusion: CNSL status remains an adverse prognostic factor in childhood B-cell ALL, indicating that additional augmentation of CNS-directed therapy is warranted for patients with CNSL at diagnosis.

Targeting metabolism: A potential strategy for hematological cancer therapy.

Most hematological cancer-related relapses and deaths are caused by metastasis; thus, the importance of this process as a target of therapy should be considered. Hematological cancer is a type of cancer in which metabolism plays an essential role in progression. Therefore, we are required to block fundamental metastatic processes and develop specific preclinical and clinical strategies against those biomarkers involved in the metabolic regulation of hematological cancer cells, which do not rely on primary tumor responses. To understand progress in this field, we provide a summary of recent developments in the understanding of metabolism in hematological cancer and a general understanding of biomarkers currently used and under investigation for clinical and preclinical applications involving drug development. The signaling pathways involved in cancer cell metabolism are highlighted and shed light on how we could identify novel biomarkers involved in cancer development and treatment. This review provides new insights into biomolecular carriers that could be targeted as anticancer biomarkers.

[Changes of intestinal flora in children with acute lymphoblastic leukemia before and after chemotherapy]. / å„¿ç«¥æ€¥æ€§æ·‹å·´ç»†èƒžç™½è¡€ç— åŒ–ç–—å‰åŽè‚ é“èŒç¾¤å˜åŒ–ç‰¹ç‚¹.

OBJECTIVES: To examine the changes of intestinal flora in children newly diagnosed with acute lymphoblastic leukemia (ALL) and the influence of chemotherapy on intestinal flora. METHODS: Fecal samples were collected from 40 children newly diagnosed with ALL before chemotherapy and at 2 weeks, 1 month, and 2 months after chemotherapy. Ten healthy children served as the control group. 16S rDNA sequencing and analysis were performed to compare the differences in intestinal flora between the ALL and control groups and children with ALL before and after chemotherapy. RESULTS: The ALL group had a significant reduction in the abundance of intestinal flora at 1 and 2 months after chemotherapy, with a significant reduction compared with the control group (P<0.05). Compared with the control group, the ALL group had a significant reduction in the diversity of intestinal flora before and after chemotherapy (P<0.05). At the phylum level, compared with the control group, the ALL group had a significant reduction in the relative abundance of Actinobacteria at 2 weeks, 1 month, and 2 months after chemotherapy (P<0.05) and a significant increase in the relative abundance of Proteobacteria at 1 and 2 months after chemotherapy (P<0.05). At the genus level, compared with the control group, the ALL group had a significant reduction in the relative abundance of Bifidobacterium at 2 weeks, 1 month, and 2 months after chemotherapy (P<0.05); the relative abundance of Klebsiella in the ALL group was significantly higher than that in the control group at 1 and 2 months after chemotherapy and showed a significant increase at 1 month after chemotherapy (P<0.05); the relative abundance of Faecalibacterium in the ALL group was significantly lower than that in the control group before and after chemotherapy and showed a significant reduction at 2 weeks and 1 month after chemotherapy (P<0.05). The relative abundance of Enterococcus increased significantly at 1 and 2 months after chemotherapy in the ALL group (P<0.05), and was significantly higher than that in the control group (P<0.05). CONCLUSIONS: The diversity of intestinal flora in children with ALL is significantly lower than that in healthy children. Chemotherapy significantly reduces the abundance of intestinal flora and can reduce the abundance of some probiotic bacteria (Bifidobacterium and Faecalibacterium) and increase the abundance of pathogenic bacteria (Klebsiella and Enterococcus) in children with ALL.

The comparison of plasma arsenic concentration and urinary arsenic excretion during treatment with Realgar-Indigo naturalis formula and arsenic trioxide in children with acute promyelocytic leukemia.

Realgar-Indigo naturalis formula (RIF) is a traditional Chinese medicine containing As4S4 and effective in treating acute promyelocytic leukemia (APL). The dose of RIF remains to be determined in pediatric patients. Comparison of plasma arsenic concentrations and toxicity between RIF and arsenic trioxide (ATO) treatment in APL may help to establish an appropriate therapeutic dose of RIF for children. From October 2018 to March 2020, 19 pediatric patients with APL treated with SCCLG-APL protocol were included, 9 in RIF group at 135 mg/kg/day orally three times daily, and 10 in ATO group at 0.16 mg/kg/day intravenously over 12 h daily. Peak and trough plasma arsenic concentrations were assayed at D1, 2, 7 and 14 of induction treatment. Urine arsenic excretions were assessed with spot urine samples and the measurements were adjusted using creatinine. Toxicities were compared between two groups. The plasma arsenic concentration reached steady state at D7 either in the RIF or ATO group, and the mean peak and trough concentrations were similar between two groups (P > 0.05), which were 0.54 µmol/L and 0.48 µmol/L in RIF group, and 0.63 µmol/L and 0.51 µmol/L in ATO group, respectively. Urine arsenic excretion rate was positively correlated with the concentration of plasma arsenic. The rates of treatment-related adverse events were similar in two groups. In conclusion, the dose of RIF at 135 mg/kg/day may be an appropriate therapeutic dose in children with APL. Urine arsenic level can be used as an indicator to estimate plasma arsenic concentration. Trial registration www.clinicaltrials.gov NCT02200978.

A Nomogram for Predicting Event-Free Survival in Childhood Acute Lymphoblastic Leukemia: A Multicenter Retrospective Study.

Objective: Even though childhood acute lymphoblastic leukemia (ALL) has an encouraging survival rate in recent years, some patients are still at risk of relapse or even death. Therefore, we aimed to construct a nomogram to predict event-free survival (EFS) in patients with ALL. Method: Children with newly diagnosed ALL between October 2016 and July 2021 from 18 hospitals participating in the South China children's leukemia Group (SCCLG) were recruited and randomly classified into two subsets in a 7:3 ratio (training set, n=1187; validation set, n=506). Least absolute shrinkage and selection operator (LASSO) and multivariate Cox regression analysis were adopted to screen independent prognostic factors. Then, a nomogram can be build based on these prognostic factors to predict 1-, 2-, and 3-year EFS. Concordance index (C-index), area under the curve (AUC), calibration curve, and decision curve analysis (DCA) were used to evaluate the performance and clinical utility of nomogram. Result: The parameters that predicted EFS were age at diagnosis, white blood cell at diagnosis, immunophenotype, ETV6-RUNX1/TEL-AML1 gene fusion, bone marrow remission at day 15, and minimal residual disease at day 15. The nomogram incorporated the six factors and provided C-index values of 0.811 [95% confidence interval (CI) = 0.792-0.830] and 0.797 (95% CI = 0.769-0.825) in the training and validation set, respectively. The calibration curve and AUC revealed that the nomogram had good ability to predict 1-, 2-, and 3-year EFS. DCA also indicated that our nomogram had good clinical utility. Kaplan-Meier analysis showed that EFS in the different risk groups stratified by the nomogram scores was significant differentiated. Conclusion: The nomogram for predicting EFS of children with ALL has good performance and clinical utility. The model could help clinical decision-making.

[Prognostic Factors Analysis of Children with Hemophagocytic Lymphohistiocytosis].

OBJECTIVE: To analyze the risk factors affecting prognosis of children with hemophagocytic lymphohistiocytosis (HLH). METHODS: The clinical manifestations and laboratory data of 143 HLH children who met the HLH-2004 diagnostic criteria in Shenzhen Children's Hospital from January 2009 to May 2017 were retrospectively analyzed, and the independent factors affecting prognosis were also analyzed. RESULTS: The median age of 143 HLH children was 1.9 (0.1-14.3) years old, and the median follow-up time was 6.7 years (1 day - 11.9 years). The overall survival rate of 1 month, 1 year, and 10 years was (87.4±5.5)%, (81.1±6.5)%, and (81.1±6.5)%, respectively. The deaths occurred within 1 year after onset. Multivariate analysis showed that central nervous system (CNS) involvement (P=0.047), low hemoglobin (P=0.002), prolonged activated partial thromboplastin time (APTT) (P<0.001), high triglyceride (P=0.005) were all the independent risk factors affecting survival of the children. Receiver operating characteristic curve indicated that APTT (AUC=0.753, P<0.001) was more valuable than other risk factors in predicting death of the children. The cut-off value of APTT was 56.6 s, and the sensitivity and specificity of which was 55.6% and 89.7%, respectively. CONCLUSION: Hypohemoglobinemia, prolonged APTT, hypertriglyceridemia, and CNS involvement the risk factors affecting prognosis of HLH, and prolonged APTT shows a strong predictive value for death.

Prognostic Value and Outcome for ETV6/RUNX1-Positive Pediatric Acute Lymphoblastic Leukemia: A Report From the South China Children's Leukemia Group.

PURPOSE: To analyzed the outcome of ETV6/RUNX1-positive pediatric acute B lymphoblastic leukemia (B-ALL) with the aim of identifying prognostic value. METHOD: A total of 2,530 pediatric patients who were diagnosed with B-ALL were classified into two groups based on the ETV6/RUNX1 status by using a retrospective cohort study method from February 28, 2008, to June 30, 2020, at 22 participating ALL centers. RESULTS: In total, 461 (18.2%) cases were ETV6/RUNX1-positive. The proportion of patients with risk factors (age <1 year or ≥10 years, WB≥50×109/L) in ETV6/RUNX1-positive group was significantly lower than that in negative group (P<0.001), while the proportion of patients with good early response (good response to prednisone, D15 MRD < 0.1%, and D33 MRD < 0.01%) in ETV6/RUNX1-positive group was higher than that in the negative group (P<0.001, 0.788 and 0.004, respectively). Multivariate analysis of 2,530 patients found that age <1 or ≥10 years, SCCLG-ALL-2016 protocol, and MLL were independent predictor of outcome but not ETV6/RUNX1. The EFS and OS of the ETV6/RUNX1-positive group were significantly higher than those of the negative group (3-year EFS: 90.11 ± 4.21% vs 82 ± 2.36%, P<0.0001, 3-year OS: 91.99 ± 3.92% vs 88.79 ± 1.87%, P=0.017). Subgroup analysis showed that chemotherapy protocol, age, prednisone response, and D15 MRD were important factors affecting the prognosis of ETV6/RUNX1-positive children. CONCLUSIONS: ETV6/RUNX1-positive pediatric ALL showed an excellent outcome but lack of independent prognostic significance in South China. However, for older patients who have the ETV6/RUNX1 fusion and slow response to therapy, to opt for more intensive treatment.

Preliminary investigation on the abnormal mechanism of CD4+FOXP3+CD25high regulatory T cells in pediatric B-cell acute lymphoblastic leukemia.

The current study aimed to investigate the changes and regulatory mechanism of cluster of differentiation (CD)4+CD25high forkhead box protein 3 (Foxp3+) regulatory T cells (Tregs) in childhood B-cell acute lymphocytic leukemia (B-ALL). A total of 18 children with B-ALL and 15 age-matched healthy children were included. Reverse-transcription quantitative polymerase chain reaction was used to evaluate the mRNA levels of Foxp3, cytotoxic T-lymphocyte associated protein 4 (CTLA4), glucocorticoid-induced tumor necrosis factor receptor (GITR), lymphocyte activation gene 3 (LAG3), interleukin (IL)-2 receptor (R)ß/γ, IL-6Rα/ß, mothers against decapentaplegic homolog (Smad)3/4 and runt-related transcription factor (RUNX)1/3 in CD4-positive cells. The concentration of cytokines in plasma were measured using a cytometric bead array. Additionally, the proportion of CD4+CD25highFoxp3+ Tregs and levels of associated proteins was analyzed using flow cytometry. The results demonstrated that the proportion of CD4+CD25highFoxp3+ and expression of Foxp3 in children with B-ALL was significantly higher compared with healthy controls (P<0.05) and that transcription levels of CTLA4, GITR and LAG3 were also significantly elevated (P<0.05). Compared with healthy controls, the expression of IL-2Rα/ß and its downstream molecule phosphorylated signal transducer and activator of transcription 5 (pSTAT5) in CD4-positive cells significantly increased (P<0.05); however, no significant difference of IL-2Rγ levels was identified between the two groups. Correlation analysis demonstrated a significant positive correlation between the expression of phosphorylated (p) signal transducer and activator of transcription factor (STAT)5 and CD4+CD25highFoxp3+ Tregs in children with B-ALL (r=0.17; P<0.05). The plasma concentration of TGF-ß, the expression of its receptor TGF-ßRI/II and downstream molecules Smad3/4 were significantly upregulated in children with B-ALL (P<0.05), whereas the expression of RUNX1/3 was lower compared with healthy controls (P<0.05). Furthermore, the expression of Smad3 and RUNX1 was positively correlated with CD4+CD25highFoxp3+ Tregs in children with B-ALL (r=0.87 and 0.60, respectively; P<0.05). Additionally, the expression of pSTAT3 in CD4-positive cells decreased significantly in pediatric patients with B-ALL when compared with healthy controls; however, plasma concentrations of IL-6 was significantly higher (P<0.05). Furthermore, a negative correlation was identified between pSTAT3 and CD4+CD25highFoxp3+ Tregs in pediatric patients with B-ALL (r=-0.39; P<0.05). However, no significant differences in IL-6Rα/ß expression were identified between the two groups. The results demonstrated that the excessive activation of IL-2/pSTAT5 and TGF-ß/Smad signaling, and insufficiency of pSTAT3 may be correlated with increased CD4+CD25highFoxp3+ Tregs in pediatric B-ALL.

Multicenter randomized trial of arsenic trioxide and Realgar-Indigo naturalis formula in pediatric patients with acute promyelocytic leukemia: Interim results of the SCCLG-APL clinical study.

Intravenous arsenic trioxide (ATO) has been adopted as the first-line treatment for acute promyelocytic leukemia (APL). Another arsenic compound named the Realgar-Indigo naturalis formula (RIF), an oral traditional Chinese medicine containing As4 S4 , has been shown to be highly effective in treating adult APL. In the treatment of pediatric APL, the safety and efficacy of RIF remains to be confirmed. This randomized, multicenter, and noninferiority trial was conducted to determine whether intravenous ATO can be substituted by oral RIF in the treatment of pediatric APL. From September 2011 to January 2017, among 92 patients who were 16 years old or younger with newly diagnosed PML-RARa positive APL, 82 met eligible criteria and were randomly assigned to ATO (n = 42) or RIF (n = 40) group. The remaining 10 patients did not fulfilled eligible criteria because five did not accept randomization, four died and one had hemiplegia prior to arsenic randomization due to intracranial hemorrhage or cerebral thrombosis. Induction and consolidation treatment contained ATO or RIF, all-trans-retinoic acid and low intensity chemotherapy. End points included event-free survival (EFS), adverse events and hospital days. After a median 3-year follow-up, the estimated 5-year EFS was 100% in both groups, and adverse events were mild. However, patients in the RIF group had significantly less hospital stay than those in the ATO group. This interim analysis shows that oral RIF is as effective and safe as intravenous ATO for the treatment of pediatric APL, with the advantage of reducing hospital stay. Final trial analysis will reveal mature outcome data.

[Brain injury after induction chemotherapy in children with acute lymphoblastic leukemia].

OBJECTIVE: To investigate the changes in brain injury after the induction chemotherapy in children with acute lymphoblastic leukemia (ALL) by cranial MRI. METHODS: The clinical data and cranial MRI results of 62 children with ALL who were hospitalized from March 2014 to June 2015 were analyzed retrospectively. RESULTS: Before chemotherapy, MRI showed bone marrow infiltration of the skull in 33 patients (53%); the children with WBC<20×10(9)/Lhad a significantly lower incidence rate of bone marrow infiltration of the skull than those with WBC≥20×10(9)/L (16 patients/42% vs 17 patients/71%; P<0.05), and the high-risk group had a significantly higher incidence rate of bone marrow infiltration of the skull than the non-high-risk group (71% vs 44%; P<0.05). Before chemotherapy, there were 4 cases (7%) of brain atrophy, and 2 cases (3%) of abnormal signals in the sensory conduction bundle. MRI reexamination in 28 patients after 3 months of chemotherapy showed 3 new cases (11%) of brain atrophy and 1 aggravated case of brain atrophy. CONCLUSIONS: The children with ALL have bone marrow infiltration of the skull, brain atrophy, and abnormal signals in the sensory conduction bundle before chemotherapy, especially bone marrow infiltration of the skull, and some changes in brain injury disappear after treatment.

[One-step multiplex RT-PCR for identifying common fusion transcripts in childhood acute lymphoblastic leukemia].

OBJECTIVE: To evaluate the efficiency of one-step multiplex RT-PCR for identifying four common fusion transcripts (TEL/AML1, E2A/PBX1, MLL/AF4 and BCR/ABL) in children with acute lymphoblastic leukemia (ALL). METHODS: Total RNA was extracted from bone marrow samples of 76 children who were newly diagnosed with ALL between January 2003 and December 2010. These RNAs were analyzed for TEL/AML1, E2A/PBX1, MLL/AF4 and BCR/ABL by one-step multiplex RT-PCR or common nested-multiplex PCR. The PCR products were confirmed by DNA sequencing. RESULTS: TEL/AML1 was found in 12 cases (the length of products was 298 bp in 9 cases and 259 bp in 3 cases), E2A/PBX1 was found in 3 cases (the length of products was 373 bp), BCR/ABL was found in 1 case (the length of products was 2 124 bp), and MLL/AF4 was found in 7 cases (the length of products was 427 bp in 1 case and 673 bp in 6 cases) using one-step multiplex RT-PCR combined with DNA sequencing. The results were consistent with those using common nested-multiplex PCR. CONCLUSIONS: One-step multiplex RT-PCR may be another alternative for detection of common fusion transcripts in children with ALL.

Effect of tumor gangliosides on tyrosine phosphorylation of p125FAK in platelet adhesion to collagen.

The exact mechanisms as to how platelets influence blood-borne metastasis remain poorly understood. Gangliosides, sialic acid-containing glycosphingolipids, are associated with tumor progression and metastasis in humans. Gangliosides isolated from tumor cells promote collagen-stimulated platelet aggregation and ATP secretion and enhance platelet adhesion to immobilized collagen. Gangliosides interact with a number of cell surface receptors including integrin receptors. In this study, we examined the effects of α2ß1 integrin-mediated platelet adhesion to collagen and phosphotyrosine signaling of focal adhesion kinase, p125FAK (FAK). platelets pre-incubated with neuroblastoma tumor gangliosides (NBTGs) or their major component GD2 (disialoganglioside) were more adherent to immobilized collagen (OD570 0.43±0.12, 0.39±0.13) compared to platelets pre-incubated with MTB (0.14±0.06, p<0.001); the effect of NBTGs was blocked by F-17 anti-α2 antibody. Pre-incubation of platelets with NBTGs resulted in a marked increase in the phosphotyrosine content of p125FAK in the adherent platelets compared to the MTB-pre-incubated adherent platelets. F-17 anti-α2 antibody decreased protein tyrosine phosphorylation of NBTG-incubated platelets adherent to collagen. These results indicate that the tumor gangliosides enhance platelet adhesion to extracellular matrix collagen by upregulating integrin α2ß1-mediated tyrosine phosphorylation of p125FAK, thereby providing insight into how this interaction may be involved in neuroblastoma metastasis.

[Evaluation of heart and liver iron deposition status in patients with ß- thalassemia intermedia and major with MRI T2* technique].

OBJECTIVE: To study the status of iron deposition in patients with ß-thalassemia intermedia and major in mainland China. METHODS: The status of transfusion and chelation was examined in 39 patients with ß-thalassemia intermedia or major. Serum ferritin levels were measured. MRI T2* technique was used to detect cardiac and hepatic iron deposition. RESULTS: Serum ferritin levels ranged from the minimum of 1500 ng/mL up to a maximum of 11491 ng/mL. From liver MRI T2* measurement, 15 cases had severe hepatic iron deposition (38%) and moderate deposition was found in 15 cases (38%), mild in 7 cases (18%), and normal in 2 cases (5%). Heart MRI T2* showed severe heart iron deposition in 7 cases (18%), mild in 5 cases (13%), and normal in 27 cases (69%). One case had cardiac arrhythmia. Four cases were over 20 years of age, and presented with gonadal function hypoplasia. The majority of patients did not receive regular transfusion and they had delayed, suboptimal chelation due to financial problems. Serum ferritin level was closely related with timing and dosage of chelation. CONCLUSIONS: In patients with ß-thalassemia who do not receive early regular transfusion and iron chelation therapy, iron deposition may occur at an early age. Important organs and tissue functional lesions and related complications also result. Relevant agencies and family members should be aware of this trend and develop appropriate strategies to improve the medical condition and quality of life of patients with this disorder.

[Status of iron metabolism and erythropoietic proliferation in children with various genotypes of thalassemia].

OBJECTIVE: To study the status of iron metabolism and erythropoietic proliferation in children with various genotypes of thalassemia. METHODS: Serum concentrations of ferritin (SF), transferrin receptor (sTfR) and erythropoietin (EPO) were measured in 158 children with thalassemia. The differences in the concentrations of the three indices among children with different genotypes of thalassemia were compared. The correlations of the hemoglobin level with sereum SF, sTfR and EPO levels were assessed. RESULTS: Among the 158 children with thalassemia, 52(32.9%) were diagnosed with alpha-thalassemia minor, 27(17.1%) with HbH disease, 59(37.4%) with beta-thalassemia minor, 13(8.2%) with beta-thalassemia major, and 7(4.4%) with combining alpha beta thalassemia. The SF levels in children with HbH disease or beta-thalassemia major were significantly higher than those in the other thalassemia groups (P<0.01). The sTfR levels in children with beta-thalassemia major were the highest when compared with those in the other thalassemia groups (P<0.05). The EPO levels in children with beta-thalassemia major were also the highest when compared with those in the other thalassemia groups (P<0.01). There was a negative correlation between hemoglobin and EPO levels in children with HbH disease (r=-0.656, P<0.01) and beta-thalassemia major (r=-0.641; P<0.05). CONCLUSIONS: The status of iron metabolism and erythropoietic proliferation is different in children with different genotypes of thalassemia. A combined measurement of SF, sTfR and EPO may reflect the status of erythropoietic proliferation.

[Experimental study on promoting the engraftment of hematopoietic stem/progenitor cell by all-trans retinoic acid].

OBJECTIVE: To explore the effect of all-trans retinoic acid (RA) on the engraftment of unrelated umbilical cord blood stem/progenitor cell transplantation (UCBT) in murine model. METHODS: 1 x 10(6) and 0.5 x 10(6) nucleated cells (NC) from C57BL/6 (H-2(b)) fetal and neonatal peripheral blood (FNPB) were separately transfused into lethally cyclophosphamide (380 mg/kg, ip) treated BALB/C (H-2(d)) recipients, 15 mg.kg(-1).d(-1) and 5 mg.kg(-1).d(-1) RA (15 mg and 5 mg RA) were administrated respectively 2 days before and after UCBT. Hematopoiesis and immune recovery, graft versus host disease (GVHD), engraftment and survival rates were then observed. RESULTS: Hematopoiesis and immune recovery occurred faster in RA treated than in untreated mice (P < 0.05). Acute GVHD was absent. The levels of engraftment were higher in both 15 mg and 5 mg RA treated mice than those in untreated controls (P < 0.05). In 1 x 10(6) NC transfused mice, 15 mg and 5 mg RA could significantly increased the 30 and 60 days survival rates from 41.67% (without RA) to 72.23% and 70.83%, respectively (P < 0.05). In 0.5 x 10(6) cells transfused mice, 15 mg and 5 mg RA increased the survival rate from 14.29% (without RA) to 42.86% and 43.48%, respectively (P < 0.05), which were comparable to that of being transfused 1 x 10(6) cells without RA treatment (P > 0.05). CONCLUSION: RA enhances the engraftment of umbilical cord blood stem/progenitor cells in murine model for UCBT. This might provide an experimental evidence of RA in clinical UCBT.

[Effects of retinoic acid on adhesion molecules expression and adhesive function in murine bone marrow stromal cell].

To explore the effect of retinoic acid (RA) on the expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in murine bone marrow stromal cell (BMSC) and adhesive rate of human cord blood mononuclear cell (UCBMNC) to BMSC in vitro, the express ions of ICAM-1 and VCAM-1 of murine BMSC were detected by flow cytometry and the binding capacity of UCBMNC to BMSC was tested by MTT assay after co-culturing with 0.1, 1.0 and 10.0 micro mol/L RA, respectively. The results showed that 1.0 and 10.0 micro mol/L RA increased the expression of ICAM-1 and the adhesive rate of U CBMNC to BMSC, however, RA did not induced the increase of expression of VCAM-1. It was positive correlation between the increments of ICAM-1 expression and the adhesive rate (r = 0.7883, P < 0.05). It is concluded that RA up-regulated ICAM-1 expression of BMSC and increased the adhesion of UCBMNC to BMSC in vitro. These may clarify the correlation between adhesion molecules on BMSC and homing of hematopoietic stem cells, and provide the experimental basis for RA to promote the homing of umbilical cord blood stem cell.