Intensive chemotherapy with dual induction and ALL-like consolidation for childhood acute myeloid leukemia: a respective report from multiple centers in China.

Background: Pediatric acute myeloid leukemia (AML) has poor prognosis and high rate of relapse and mortality, and exploration of new treatment options is still critically needed. Objectives: To summarize the outcome of our new treatment strategies for pediatric AML, which is characterized by dual induction and acute lymphoblastic leukemia (ALL) elements consolidation. Design: Retrospective, single-arm study. Methods: From July 2012 to December 2019, an intensive chemotherapy protocol was used for newly diagnosed children with AML, which contains dual induction, three courses of consolidations based on high-dose cytarabine, and two courses of consolidations composed of high-dose methotrexate, vincristine, asparaginase, and mercaptopurine (ALL-like elements). Blasts were monitored by bone marrow smears at intervals, and two lumbar punctures were performed during chemotherapy. We retrospectively analyzed the efficacy and safety of this study. The last follow-up was on 26 May 2023. Results: A total of 70 pediatric AMLs were included. The median age at diagnosis was 6.7 (0.5-16.0) years. The median initial WBC count was 23.74 × 109/L, 11 of whom ⩾100 × 109/L. After dual induction, there were 62 cases of complete remission (CR), 5 cases of partial remission, and 3 cases of nonremission. The CR rate was 88.57%. The median follow-up time was 5.8 (0.2-9.4) years, the 5-year overall survival was 78.2% ± 5%, the event-free survival (EFS) was 71.2% ± 5.6%, and the cumulative recurrence rate was 27.75%. The 5-year EFS of patients with initial WBC < 100 × 109/L (n = 59) and ⩾100 × 109/L (n = 11) were 76.4% ± 5.7% and 45.5% ± 15% (p = 0.013), respectively. A total of 650 hospital infections occurred. The main causes of infection were respiratory tract infection (26.92%), septicemia (18.46%), stomatitis (11.85%), and skin and soft-tissue infection (10.46%). Conclusion: This intensive treatment protocol with dual induction and ALL-like elements is effective and safe for childhood AML. Initial WBC ⩾ 100 × 109/L was the only independent risk factor in this cohort. Trial registration: It is a retrospective study, and no registration on ClinicalTrials.gov.

Combination of C-Reactive Protein and Procalcitonin in Distinguishing Fungal from Bacterial Infections Early in Immunocompromised Children.

Invasive fungal infection (IFI) is life-threatening in children with cancer and hematology disorders, especially when diagnosis and treatment are delayed. Conventional ß-D-glucan and galactomannan tests have poor positive predictive values in the diagnosis of IFI in children with cancer. This study aims to access the diagnostic performance of C-reactive protein (CRP) and procalcitonin (PCT) in differentiating IFI from bacterial bloodstream infections in children with malignant and hematology disorders. CRP and PCT levels were measured in samples taken from patients between 12 and 24 h after fever onset, of which 24 and 102 were in the IFI and bacterial groups, respectively. We found that the CRP levels were much higher in the IFI group than the bacterial group (100.57 versus 40.04 mg/L, median, p < 0.001), while the PCT levels remained significantly lower (0.45 versus 1.29 µg/L, median, p = 0.007). Both CRP and PCT showed significant diagnostic utilities with an area under the curve (AUC) of 0.780 (95% CI, 0.664−0.896, p < 0.001) and 0.731 (95% CI, 0.634−0.828, p < 0.001) when using the cut-off values of 94.93 mg/L and 2.00 µg/L, respectively. However, the combined biomarker of CRP and PCT yielded a better diagnostic performance with an AUC of 0.934 (95% confidential interval (CI), 0.881−0.987, p < 0.001), which was significantly higher than that of CRP or PCT (both p < 0.001), with a sensitivity of 87.5% and a specificity of 87.3%. Our study demonstrates high levels of CRP combined with low PCT could differentiate IFI from bacterial bloodstream infections in immunocompromised children.

Voriconazole Induced Hallucinations and Visual Disturbances in a Female Child: A Case Report and Literature Review.

Voriconazole is a second-generation azole widely used for the prevention and treatment of fungal infection in leukemia patients. We report a case of 9-year-old girl with T-cell acute lymphoblastic leukemia who developed hallucinations and visual disturbance after using voriconazole twice. These symptoms began acutely after treatment with voriconazole and resolved rapidly when the voriconazole was stopped. No specific cause was identified, and thus the symptoms were considered to be the adverse drug reactions (ADRs) of voriconazole. Simultaneous development of hallucinations and visual disturbance caused by voriconazole in children rarely have been reported before and the causes of these ADRs are unknown. Several other cases of hallucinations and (or) visual disturbance caused by voriconazole among 15-81 years old patients have been reported in the literature, and are reviewed. Those patients reminded us of the importance of being aware of hallucinations and visual disturbance associated with voriconazole treatment. In addition, we speculate that the hallucinations and visual disturbance are not related to the dosage form of voriconazole. We emphasize that it is also important to monitor the concentration of voriconazole regularly to avoid potential toxicity.

MTHFR-C677T Gene Polymorphism and Susceptibility to Acute Lymphoblastic Leukemia in Children: A Meta-Analysis.

BACKGROUND: The association between methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism (rs1801133) and childhood acute lymphoblastic leukemia (ALL) is inconsistent. OBJECTIVE: To explore the relationship between MTHFR-C677T polymorphism and susceptibility to childhood ALL. METHODS: PubMed, EMBASE, Web of Science, CNKI, Wanfang, VIP, and other databases were searched from the establishment of the database to November 2019, and all the case-control studies that met the inclusion criteria were collected. Stata 15.0 was used for meta-analysis, with calculation of the odds ratio (OR) of the relationship between MTHFR-C677T polymorphism and childhood ALL susceptibility. Ethnicity was analyzed by subgroup analysis. RESULTS: A total of 26 studies were included in this meta-analysis, including 4,682 children with ALL and 7144 controls. The results showed that there was no significant difference in the comparison of population of allele model, dominant gene model, recessive gene model, homozygous gene model, heterozygous gene model, and the comparison of Caucasian children. The results of the Asian child analysis suggested that the combined OR of the dominant gene model (CC + CT versus TT), homozygous model (CC versus TT) and heterozygous model (CT versus TT) was 1.32 (95% confidence interval [CI]: 1.03-1.70), 1.37 (95% CI: 1.02-1.84), and 1.27 (95% CI: 1.01-1.59), respectively, with statistically significant differences. However, there was no significant difference between the allele model and recessive gene model among Asian children. CONCLUSION: The MTHFR C677T polymorphism is related to ALL in children, especially in Asian children. CC + CT, CC, and CT genotypes can increase the risk of ALL, but no association has been found in Caucasian children.

Arsenic trioxide induces autophagic degradation of the FLT3-ITD mutated protein in FLT3-ITD acute myeloid leukemia cells.

The prognosis of acute myeloid leukemia (AML) with FMS-like tyrosine kinase 3 internal tandem duplication (FLT3-ITD) mutations is poor. Some studies, including our previous study, have indicated that arsenic trioxide (ATO) exhibited significant anti-carcinogenic activity in FLT3-ITD AML cells and explored the possibility of targeting the FLT3-ITD protein for degradation as a therapy. Autophagy is a critical mechanism of the anti-leukemic effects of ATO. In this study, we explored the therapeutic efficacy of ATO treatment in a mouse model bearing FLT3-ITD AML and found that ATO significantly reduced the leukemic burden in bone marrow and spleen. We also found that autophagy was responsible for, at least in part, the degradation of the FLT3-ITD protein by ATO. After ATO treatment, MV4-11 cells showed complete autophagic flux. The autophagy inhibitor bafilomycin A or down-regulation of the key autophagy genes Atg5 and Atg7 reversed the FLT3 degradation induced by ATO. We also found that p62/SQSTM1 delivered FLT3-ITD proteins to the lysosome, where they were subsequently degraded. These results indicate that ATO can induce autophagic degradation of the FLT3-ITD mutated protein in FLT3-ITD AML.

A new therapy in Epstein-Barr virus-associated lymphoproliferative disease: a case report and a revision of the literature.

BACKGROUND: Systemic chronic active Epstein-Barr virus infection is an extremely rare childhood disease. Since chronic active Epstein-Barr virus infection can trigger the onset of Epstein-Barr virus-associated lymphoproliferative disease. The clinical manifestations of the disease vary according to the site of involvement; therefore, management may be challenging. Currently, there are no standardized guidelines for treating Chronic active Epstein-Barr virus infection effectively. CASE PRESENTATION: We report a case of chronic active Epstein-Barr virus infection in a 5-year-old Chinese boy with intestinal, vascular, and neurological involvement. At age of 2 years and 7 months old, he had hepatomegaly and been diagnosed with Epstein-Barr virus infection. After treatment, he showed some clinical improvement. At age of 3 years and 3 months old, he presented with recurrent fever and diarrhea. Then he received methylprednisolone for 1 year and his symptoms ameliorated. At the age of 5 years, his symptoms recurred and had gastrointestinal hemorrhage and developed polyuria, frequent convulsions and hyponatremia. He was transferred to our hospital for further management. He was unconscious on admission and was diagnosised Epstein-Barr virus-lymphoproliferative disorder, based on the results in situ hybridization of EBV-encoded miRNA in sigmoid colon. Three-dimensional CT angiography demonstrated an aneurysm in the right internal carotid artery. Abdominal CT showed dilatation of vessels in part of the intestinal wall. He was also diagnosised Epstein-Barr virus encephalitis based on the elevated Epstein-Barr virus antibody titers and presence of Epstein-Barr virus DNA in the Cerebrospinal Fluid. A repeated duodenal artery embolization and symptomatic therapy could not control the hemorrhage after admission. He subsequently received treatment with ganciclovir, glucocorticoid, thalidomide, and propranolol. Hemorrhage was controlled in 5 days; his symptoms improved. The fever did not recur and the CSF pressure was also normalized. A follow-up CT at 3 months after admission showed regression of the aneurysm in the right internal carotid artery and the vascular lesion in the duodenum. DISCUSSION AND CONCLUSIONS: A new treatment protocol including thalidomide and propranolol resulted in a marked improvement in his clinical symptoms, and shows promise as a novel and effective therapeutic approach for Chronic active Epstein-Barr virus infection-associated lymphoproliferative disorder.

Potential Role of HMGCS2 in Tumor Angiogenesis in Colorectal Cancer and Its Potential Use as a Diagnostic Marker.

Objective: HMGCS2 is the rate-limiting enzyme of ketogenesis, which is vital for tumor initiation or metastasis. The aim of this study is to determine the relationship between HMGCS2 and tumor angiogenesis. Materials and Methods: The study consisted of 100 cases with colorectal cancer and healthy control, the expression of HMGCS2 and the microvessel density (MVD) (marker: CD31) were analyzed by immunohistochemistry and tube formation, and the centration of ß-hydroxybutyrate in serum was assessed by biochemical analysis. Results: The results showed that HMGCS2 expression is significantly reduced in colorectal cancer compared with healthy control, which is inversely correlated with MVD in colorectal cancer by IHC analysis. What is more, knockdown HMGCS2 expression in HT-29 cells significantly contributed endothelial cell tube formation. Conclusion: These findings implying HMGCS2 may have a negative regulation of tumor angiogenesis and provide an approach to inhibit tumor angiogenesis.

Melatonin inhibits MLL-rearranged leukemia via RBFOX3/hTERT and NF-κB/COX-2 signaling pathways.

MLL-rearranged leukemia is an aggressive malignancy associated with poor outcome, which is refractory to conventional treatment. Melatonin has been proven to exert anti-tumor activity, but the effect of melatonin on MLL-r leukemia and the underlying mechanism remain poorly understood. In this study, melatonin inhibited cell proliferation and induced apoptosis by activating the caspase-dependent apoptotic pathway in MLL-r leukemia cells. Mechanistic investigations revealed that melatonin suppressed the expression of hTERT by abrogating the binding activity of RBFOX3 to the hTERT promoter. Melatonin also blocked NF-κB nuclear translocation and suppressed NF-κB binding to the COX-2 promoter, thereby suppressing the expression of COX-2. In addition, clinical samples revealed that melatonin exerts anti-leukemic activity in primary MLL-r leukemia blasts ex vivo. In vivo, the mice treated with melatonin experienced a larger reduction in leukemic burden than the control group in a MLL-r leukemia xenograft mouse model. Collectively, these results suggest that melatonin inhibits MLL-rearranged leukemia through suppressing the RBFOX3/hTERT and NF-κB/COX-2 signaling pathways. Our findings provide new insights into the role of melatonin for MLL-r leukemia treatment.

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.

MiR-124 contributes to glucocorticoid resistance in acute lymphoblastic leukemia by promoting proliferation, inhibiting apoptosis and targeting the glucocorticoid receptor.

Acute lymphoblastic leukemia (ALL) is characterized by the accumulation of abnormal lymphoblasts in the bone marrow and blood. Though great progress has been made for improvement in clinical treatment during the past decades, some children with ALL still relapsed. Glucocorticoid (GC) resistance is an important clinical problem for ALL treatment failure. Therefore, further understanding of the mechanism of GC resistance and exploring novel therapeutic strategies are crucial for improving treatment outcome. The reported involvement of microRNAs (miRNAs) in drug resistance implied that deregulated miRNA expression might contribute to GC treatment response of ALL. However, individual miRNAs and their functional mechanisms potentially involved in the GC response are still largely unknown. In the present study, we found that miR-124 was up-regulated in prednisone insensitive human ALL cell line and prednisone-poor response ALL patients. Furthermore, it was found that miR-124 might contribute to GC resistance by promoting proliferation and inhibiting apoptosis of ALL cells. Importantly, we validated that miR-124, targeted and decreased the expression of glucocorticoid receptor (NR3C1), prevented the inhibitory effect of GC in ALL. These findings strongly suggest that miR-124 is critical in poor GC response and may serve as a potential therapeutic target in ALL with poor GC resistance.

Arsenic trioxide and all-trans-retinoic acid selectively exert synergistic cytotoxicity against FLT3-ITD AML cells via co-inhibition of FLT3 signaling pathways.

FLT3-ITD mutations occur in approximately 30% of acute myeloid leukemia (AML) and are associated with a poor outcome. Currently available FLT3 inhibitors have in vitro but limited clinical activity in FLT3-ITD AML. Reports have shown that an arsenic trioxide (ATO)/all-trans-retinoic acid (ATRA) combination improves prognosis in acute promyelocytic leukemia, especially with FLT3-ITD, and ATO or ATRA alone enhances apoptosis in FLT3-ITD AML cells treated with FLT3 inhibitors, providing a rationale to investigate the role of ATO/ATRA in FLT3-ITD AML. Here, we demonstrate that an ATO/ATRA combination selectively exerts synergistic cytotoxicity against FLT3-ITD AML cell lines (MV4;11/MOLM-13). The signaling pathways affected by ATO/ATRA include FLT3/STAT5/MYC, FLT3/STAT5/E2F1, FLT3/ERK/ATF5 and FLT3/AKT/ATF5.ATF5 may function as an oncogene in FLT3-ITD AML. Our findings provide experimental evidence that supports further exploration of ATO/ATRA in FLT3-ITD AML in vivo and warrants a clinical evaluation of regimens comprising an ATO/ATRA combination.

MicroRNA-185-5p restores glucocorticoid sensitivity by suppressing the mammalian target of rapamycin complex (mTORC) signaling pathway to enhance glucocorticoid receptor autoregulation.

Overexpression of microRNA-185-5p (miR-185-5p) in glucocorticoid (GC)-sensitive acute lymphoblastic leukemia (ALL) was identified using a microarray and reverse transcription polymerase chain reaction and was further confirmed in ALL cell lines. A reporter assay confirmed that the Rictor-one component of mammalian target of rapamycin complex 2 (mTORC2) is a target of miR-185-5p. Decreased mTORC activity was also confirmed in GC-sensitive patients. Overexpression of miR-185-5p significantly enhanced GC sensitivity in CEM-C1 cells (GC resistance) by increasing the rate of cell apoptosis and cycle arrest, and decreasing cell survival, accompanied by a decrease in mTORC activity and an increase in GC-induced glucocorticoid receptor (GR) expression. Rapamycin, an mTORC1 inhibitor, showed similar effects to miR-185-5p. These results demonstrated that miR-185-5p enhances GC sensitivity via suppression of mTORC activity by enhancing GR autoupregulation and that miR-185-5p is a potential target for the diagnosis and reversion of GC resistance.

Butein inhibits cell proliferation and induces cell cycle arrest in acute lymphoblastic leukemia via FOXO3a/p27kip1 pathway.

Acute lymphoblastic leukemia (ALL) is a common hematological malignancy characterized by the uncontrolled proliferation of leukemia cells in children. Discovering and developing effective chemotherapeutic drugs are needed for ALL. In this study, we investigated the anti-leukemic activity of butein and its action mechanisms in ALL. Butein was found to significantly suppress the cellular proliferation of ALL cell lines and primary ALL blasts in a dose-dependent manner. It also induced cell cycle arrest by decreasing the expression of cyclin E and CDK2. We also found that butein promoted nuclear Forkhead Class box O3a (FOXO3a) localization, enhanced the binding of FOXO3a on the p27kip1 gene promoter and then increased the expression of p27kip1. Moreover, we showed that FOXO3a knockdown significantly decreased the proliferation inhibition by butein, whereas overexpression of FOXO3a enhanced the butein-mediated proliferation inhibition. However, overexpression of FOXO3a mutation (C-terminally truncated FOXO3a DNA-binding domain) decreased the proliferation inhibition by butein through decreasing the expression of p27kip1. Our results therefore demonstrate the therapeutic potential of butein for ALL via FOXO3a/p27kip1 pathway.

A phosphoproteomic study reveals shp-1 cleavage reprograms LPS signaling via a PI-3K/NF-κB and mTORC1 related mechanism.

The reprogrammed lipopolysaccharide (LPS) pathway has been reported to render patients more susceptible to the development of post-traumatic multiple organ dysfunction syndrome (MODS). To facilitate thorough understanding of this mechanism, a phosphoproteomic study was utilized to screen the potential signaling molecules. Interestingly, a truncated form of Src homology 2-domain-containing tyrosine phosphatase 1 (shp-1) emerged in human THP-1 macrophages sequentially treated with H2O2 and LPS and not with either of the treatments alone. Subsequent immunoblot analysis confirmed the cleavage of shp-1 and reduction of shp-1 activity in rat alveolar macrophages, mast cells, and neutrophils. Mechanistically, calpain is essential but not sufficient for shp-1 cleavage. In addition, shp-1 cleavage renders the activation of phosphatidylinositol 3-kinase (PI-3K)/nuclear factor-κB (NF-κB) and mechanistic target of rapamycin complex 1 (mTORC1) in macrophages, resulting in enhanced cytokine induced neutrophil chemoattractant (CINC) secretion, which is critical for neutrophil recruitment in MODS. On the other hand, shp-1 cleavage results in the activation of PI-3K/Akt, enhancing the survival of neutrophils. Collectively, these results highlight the cleavage of shp-1 as a critical event in reprogramming LPS pathway to promote both neutrophil recruitment and survival and provide a novel mechanistic framework for the investigation of the post-traumatic MODS.

Fluorescent probe based on heteroatom containing styrylcyanine: pH-sensitive properties and bioimaging in vivo.

A novel fluorescent probe based on heteroatom containing styrylcyanine is synthesized. The fluorescence of probe is bright green in basic and neutral media but dark orange in strong acidic environments, which could be reversibly switched. Such behavior enables it to work as a fluorescent pH sensor in the solution state and a chemosensor for detecting acidic and basic volatile organic compounds. Analyses by NMR spectroscopy confirm that the protonation or deprotonation of pyridinyl moiety is responsible for the sensing process. In addition, the fluorescent microscopic images of probe in live cells and zebrafish are achieved successfully, suggesting that the probe has good cell membrane permeability and low cytotoxicity.

Flavokawain B inhibits the growth of acute lymphoblastic leukemia cells via p53 and caspase-dependent mechanisms.

The development of novel chemotherapeutic drugs is needed for the treatment of patients with acute lymphoblastic leukemia (ALL). In this study, the anti-leukemic effect and the potential molecular mechanisms of action of flavokawain B on ALL were investigated. Flavokawain B was found to significantly inhibit the cellular proliferation of B-ALL and T-ALL cell lines in a dose-dependent manner. It also induced cellular apoptosis by increasing the expression of p53, Bax and Puma, and activating the cleavage of caspase-3 and poly ADP-ribose polymerase (PARP). Furthermore, the enhancement of p53-dependent apoptosis by flavokawain B could be rescued by pifithrin-α, a pharmacological inhibitor of p53 transcriptional activity. Moreover, the proliferation of leukemia blast cells from 16 patients with ALL was inhibited by flavokawain B, and tumor growth in xenograft mice was also suppressed by this drug. In conclusion, our results demonstrate the therapeutic potential of flavokawain B for the treatment of ALL.

Poly(phenyleneethynylene) nanoparticles: preparation, living cell imaging and potential application as drug carriers.

Conjugated polymer nanoparticles (PPE nanoparticles) are fabricated by the self-assembly of novel amphiphilic poly(phenyleneethynylenes). The morphology and cytotoxicity of PPE nanoparticles were investigated. Moreover, confocal fluorescence microscopy and flow cytometry assay revealed the effective internalization of PPE nanoparticles. PPE nanoparticles were also used as a carrier for drug delivery systems. Upon encapsulating an anticancer drug, DOX, PPE nanoparticles exhibited high drug loading efficiency (26.6 wt%) and good release properties. Subsequently, DOX loaded PPE nanoparticles were investigated by employing dynamic light scattering and transmission electron microscopy. Finally, cell uptake, cytotoxicity and Western blotting analysis were carried out, which revealed that PPE nanoparticles successfully deliver the drug into cancer cells and retain the anticancer bioactivity of DOX. All these results indicated that this new type of PPE nanoparticles would be a promising drug delivery system for therapeutic delivery and/or bioimaging applications.

Mandibuloacral dysplasia type A-associated progeria caused by homozygous LMNA mutation in a family from Southern China.

BACKGROUND: Mandibuloacral dysplasia type A (MADA) is a rare autosomal recessive disorder, characterized by growth retardation, skeletal abnormality with progressive osteolysis of the distal phalanges and clavicles, craniofacial anomalies with mandibular hypoplasia, lipodystrophy and mottled cutaneous pigmentation. Some patients may show progeroid features. MADA with partial lipodystrophy, more marked acral, can be caused by homozygous or compound heterozygous mutation in the gene encoding lamin A and lamin C (LMNA). MADA and Hutchinson-Gilford progeria syndrome are caused by the same gene and may represent a single disorder with varying degrees of severity. MAD patients characterized by generalized lipodystrophy (type B) affecting the face as well as extremities and severe progressive glomerulopathy present heterozygous compound mutations in the ZMPSTE24 gene. CASES PRESENTATIONS: We described a rare pedigree from Southern China, among them all three children presented with phenotypes of MADA associated progeria. The two elder sisters had developed severe mandibular hypoplasia associated progeria since the age of 1 year. The eldest sister showed a progressive osteolysis. The youngest son of 10 months showed severer lesions than those of his sisters at the same age, and presented possible muscle damage, and his symptoms progressed gradually. Three genes mutations including LMNA, ZMPSTE24 and BANF1 were tested in the family. LMNA gene sequencing revealed a homozygous missense mutation, c.1579C > T, p.R527C for all three siblings, and heterozygous mutations for their parents, whereas no mutations of ZMPSTE24 and BANF1 genes was detected among them. CONCLUSIONS: The same homozygous mutation of c.1579C > T of LMNA gene led to MADA associated progeria for the present family. The course of osteolysis for MADA is progressive.

MiR-99a may serve as a potential oncogene in pediatric myeloid leukemia.

BACKGROUND: Leukemia is the most common malignant proliferative disease in children. Our previous study found that miR-99a was up-regulated in pediatric primary AML using microRNA expression profiles. Up to date, although there is a certain number of reports on microRNA expression features and functions in pediatric acute myeloid leukemia (AML) and chronic myeloid leukemia (CML), the expression and function of miR-99a in these diseases remain to be investigated. METHODS: qRT-PCR was performed to measure the expression level of miR-99a in 88 samples including 68 pediatric acute myeloid leukemia patients, 8 chronic myeloid leukemia patients and 12 pediatric controls. MTT assay, apoptosis assay, dual-luciferase reporter transfection assay and western blot analysis were used to investigate the function of miR-99a. RESULTS: MiR-99a was highly expressed in pediatric-onset AML (M1-M5) and CML, while significantly lowly expressed during complete remission of these diseases. MTT assay indicated that the proliferations of K562 and HL60 cells were significantly promoted by miR-99a, and apoptosis assessment by Annexin V/propidium iodide staining demonstrated that the apoptosis of these cells was inhibited by miR-99a. Additionally, dual-luciferase reporter transfection assay and western blot analysis indicated that miR-99a may target CTDSPL and TRIB2, which are two tumor suppressor genes. CONCLUSIONS: This study revealed that miR-99a may play a potential oncogenic role in pediatric myeloid leukemia including AML and CML via regulating tumor suppressors CTDSPL and TRIB2, suggesting that these two leukemias might share some common biological pathways involved in the generation and development of disease and miR-99a could be a common therapeutic target for myeloid leukemias treatment.

[AXIN1-related CSRNP1 mRNA expression and its transcriptional regulation in TGF-ß1-induced tumor cells].

OBJECTIVE: To investigate AXIN1-related CSRNP1 gene expression and the mechanism of its transcriptional regulation in TGF-ß1-induced tumor cells. METHODS: Human lung carcinoma A549 cells or human prostate cancer PC3 cells were treated with TGF-ß1 at different doses (0, 20, 40, and 80 ng/ml) or at 20 ng/ml for 0, 8, 12, or 24 h, and the dose and time effect of TGF-ß1 on CSRNP1 mRNA expression in the tumor cells were evaluated with real-time RT-PCR. A549 cells were also treated with TGF-ß1 and cycloheximide to clarify whether CSRNP1 expression induced by TGF-ß1 required de novo protein synthesis. A549 cells transfected with pcDNA3.1, flag-SMAD3, or flag-SMAD3-mu, after serum starvation, were treated with or without TGF-ß1 (20 ng/mL) for 24 h, and the overexpression of wild-type SMAD3 and dominant negative SMAD3-mu mutant were confirmed by Western blotting. The effect of SMAD3 or SMAD3-mu overexpression on CSRNP1 mRNA expression was also measured by real-time RT-PCR. RESULTS: In both A549 and PC3 cells, TGF-ß1 dose- and time-dependently stimulated CSRNP1 expression, which required de novo protein synthesis in A549 cells. Overexpression of wild-type SMAD3 significantly increased the expression of CSRNP1 mRNA induced by TGF-ß1, while overexpression of dominant negative SMAD3 mutant remarkably reduced CSRNP1 mRNA expression in response to TGF-ß1 in A549 cells. CONCLUSION: TGF-ß1 may contribute to CSRNP1 expression through SMAD3 activation and downstream signaling in tumor cells.