Allogeneic hematopoietic stem cell transplantation in acute leukemia patients with the SET-NUP214 fusion gene: Efficacy and survival analysis / 中华内科杂志

Objective: To investigate the clinical efficacy of allogeneic hematopoietic stem cell transplantation (allo-HSCT) for patients with acute leukemia who are positive for the SET-NUP214 fusion gene (SET-NUP214+AL). Methods: This was a retrospective case series study. Clinical data of 18 patients with SET-NUP214+AL who received allo-HSCT in the First Affiliated Hospital of Soochow University and Soochow Hongci Hematology Hospital from December 2014 to October 2021 were retrospectively analyzed to investigate treatment efficacy and prognosis. The Kaplan-Meier method was used for survival analysis. Results: Of the 18 patients, 12 were male and 6 were female, and the median age was 29 years (range, 13-55 years). There were six cases of mixed phenotype acute leukemia (three cases of myeloid/T, two cases of B/T, one case of myeloid/B/T), nine cases of acute lymphoblastic leukemia (ALL) (one case of B-ALL and eight cases of T-ALL), and three cases of acute myeloid leukemia. All patients received induction chemotherapy after diagnosis, and 17 patients achieved complete remission (CR) after chemotherapy. All patients subsequently received allo-HSCT. Pre-transplantation status: 15 patients were in the first CR, 1 patient was in the second CR, 1 was in partial remission, and 1 patient did not reach CR. All patients were successfully implanted with stem cells. The median time of granulocyte and platelet reconstitution was +12 and +13 days, respectively. With a median follow-up of 23 (4-80) months, 15 patients survived, while 3 patients died. The cause of death was recurrence of SET-NUP214+AL after transplantation. After allo-HSCT, 5 patients relapsed. The estimated 3-year overall survival (OS) and relapse-free survival (RFS) rates were 83.3%±15.2% and 55.4%±20.7%, respectively. Among the 15 patients who achieved CR before transplantation, there was no significant difference in OS and RFS between haploidentical HSCT and matched sibling donor HSCT (all P>0.05). Conclusions: Allo-HSCT can improve the prognosis and long-term survival rate of patients with SET-NUP214+AL. Disease recurrence is the most important factor affecting long-term survival.

Clinical Analysis of SET-NUP214 Fusion Gene Positive Patients with Acute Leukemia / 中国实验血液学杂志

OBJECTIVE@#To analyze the characteristics and prognosis of acute leukemia(AL) with SET-NUP214 fusion gene.@*METHODS@#The clinical data of 17 patients over 14 years old newly diagnosed with SET-NUP214 positive AL admitted in Institute of Hematology and Blood Diseases Hospital from August 2017 to May 2021 were analyzed retrospectively.@*RESULTS@#Among the 17 SET-NUP214 positive patients, 13 cases were diagnosed as T-ALL (ETP 3 cases, Pro-T-ALL 6 cases, Pre-T-ALL 3 cases, Medullary-T-ALL 1 case), AML 3 cases (2 cases M5, 1 case M0) and ALAL 1 case. Thirteen patients presented extramedullary infiltration at initial diagnosis. All 17 patients received treatment, and a total of 16 cases achieved complete remission (CR), including 12 cases in patients with T-ALL. The total median OS and RFS time were 23 (3-50) months and 21 (0-48) months, respectively. Eleven patients received allogeneic hematopoietic stem cell transplantation(allo-HSCT), with median OS time of 37.5 (5-50) months and median RFS time of 29.5 (5-48) months. The median OS time of 6 patients in chemotherapy-only group was 10.5 (3-41) months, and median RFS time of 6.5 (3-39) months. The OS and RFS of patients with transplantation group were better than those of chemotherapy-only group (P=0.038). Among the 4 patients who relapsed or refractory after allo-HSCT, the SET-NUP214 fusion gene did not turn negative before transplantation. While, in the group of 7 patients who have not relapsed after allo-HSCT till now, the SET-NUP214 fusion gene expression of 5 patients turned negative before transplantation and other 2 of them were still positive.@*CONCLUSION@#The fusion site of SET-NUP214 fusion gene is relatively fixed in AL patients, often accompanied by extramedullary infiltration. The chemotherapy effect of this disease is poor, and allo-HSCT may improve its prognosis.

Clinical Characteristics and Prognosis of Adult Acute Myeloid Leukemia with NUP98 Gene Rearrangement / 中国实验血液学杂志

OBJECTIVE@#To investigate the clinical characteristics, outcomes and prognosis of adult acute myeloid leukemia (AML) patients with NUP98 gene rearrangement.@*METHODS@#The clinical data of adult AML patients with NUP98 gene rearrangement from January 2015 to December 2019 were retrospectively analyzed, including clinical characteristics, laboratory examination, genetic anomaly, treatment strategy and survival.@*RESULTS@#A total of 15 patients with NUP98 gene rearrangement were detected in 410 adult AML patients (3.7%). The ratio of male to female among 15 patients was 1.1∶1, and the median age was 43 (17-76) years old. The main FAB types were M2 and M4/M5, and including one unclassified. According to the genetic prognosis, 11 cases were intermediate risk, while 4 cases were high risk. The main type of NUP98 gene rearrangement was NUP98-HOXA9 (13/15, 86.7%). 10 patients underwent next generation sequencing, in which 5 patients showed epigenetic gene mutations, 3 patients showed FLT3-ITD or WT1 mutations, and 2 patients showed no mutation. After induction therapy, 13 of 15 patients achieved complete remission（CR）. 7 of 8 patients with standard induction therapy achieved CR. 7 elder or intolerance patients with demethylation drug and chemotherapy all achieved CR. The median follow-up time was 28 months. The median OS of 15 the patients was 31.5 months (95% CI 10.7%-52.2%), and the median OS of the patients in non-allogeneic hematopoietic stem cell transplantation (Allo-HSCT) group was 18.5 months (95% CI 17.8%-19.1%). The median OS was not reached for the patients in the Allo-HSCT group.@*CONCLUSION@#Allo-HSCT can significantly improve the prognosis of AML patients with NUP98 rearrangement. NUP98 rearrangement can be accompanied by epigenetic gene mutations. For the elderly or patients who do not tolerate standard induction therapy, demethylation drugs combined with chemotherapy can achieve good outcomes.

Impaired Nucleoporins Are Present in Sporadic Amyotrophic Lateral Sclerosis Motor Neurons that Exhibit Mislocalization of the 43-kDa TAR DNA-Binding Protein

BACKGROUND AND PURPOSE: Disruption of nucleoporins has been reported in the motor neurons of patients with sporadic amyotrophic lateral sclerosis (sALS). However, the precise changes in the morphology of nucleoporins associated with the pathology of the 43-kDa TAR DNA-binding protein (TDP-43) in the disease process remain unknown. We investigated the expression of nucleoporins that constitute the nuclear pore complex (NPC) in spinal motor neurons that exhibit sALS in relation to TDP-43 pathology, which is a reliable neuropathological hallmark of sALS. METHODS: Paraffin-embedded sections of the lumbar spinal cord were obtained for immunofluorescence analysis from seven control subjects and six sALS patients. Anti-TDP-43 antibody, anti-nucleoporin p62 (NUP62) antibody, and anti-karyopherin beta 1 (KPNB1) antibody were applied as primary antibodies, and then visualized using appropriate secondary antibodies. The sections were then examined under a fluorescence microscope. RESULTS: NUP62 and KPNB1 immunoreactivity appeared as a smooth round rim bordering the nuclear margin in normal spinal motor neurons that exhibited nuclear TDP-43 immunoreactivity. sALS spinal motor neurons with apparent TDP-43 mislocalization demonstrated irregular, disrupted nuclear staining for NUP62 or KPNB1. Some atrophic sALS spinal motor neurons with TDP-43 mislocalization presented no NUP62 immunoreactivity. CONCLUSIONS: Our findings suggest a close relationship between NPC alterations and TDP-43 pathology in the degenerative process of the motor neurons of sALS patients.

Detection of Autoantibodies Against Nucleoporin p62 in Sera of Patients With Primary Biliary Cholangitis

BACKGROUND: Primary biliary cholangitis (PBC) is an autoimmune liver disease characterized by specific autoantibodies. We evaluated the prevalence of autoantibodies against nucleoporin p62 (anti-p62) in PBC patients' sera to determine whether it can be a marker for PBC, in comparison with other immunological and biochemical parameters. We validated the performance of our in-house ELISA technique. METHODS: Serum samples were collected from 135 PBC patients. Thirty patients with primary sclerosing cholangitis (PSC) and 30 with autoimmune hepatitis (AIH) were included as pathological controls, and 40 healthy blood donors served as healthy controls. The presence of anti-p62 was determined by an in-house ELISA using a recombinant protein. We calculated the sensitivity, specificity, positive and negative predictive values (PPV and NPV), and positive and negative likelihood ratio (LR+ and LR−) of our in-house ELISA for diagnosing PBC based on anti-p62. Findings were correlated with biochemical data and survival. RESULTS: Anti-p62 was detected in 32 PBC patients (23.7%). Specificity and PPV of anti-p62 for PBC were 99% and 97%, respectively. The difference between proportions of anti-p62-positive patients and controls was 0.23 (95% confidence interval [CI]: 0.03–0.40; P < 0.0001); LR+ and LR− were 23.7 and 0.77, respectively. The presence of anti-p62 was associated with higher levels of bilirubin and alkaline phosphatase (P < 0.001). The odds ratio for survival was 2.44 (95% CI: 0.87–6.87; P=0.091). CONCLUSIONS: Anti-p62 may be regarded as a significant serological marker of PBC.

Mitochondrial aldehyde dehydrogenase 2 protects against high glucose-induced injury in neonatal rat cardiomyocytes by regulating CaN-NFAT3 signaling pathway / 南方医科大学学报

OBJECTIVE@#To investigate whether CaN-NFAT3 pathway mediates the protective effects of aldehyde dehydrogenase (ALDH) 2 in high glucose-treated neonatal rat ventricular myocytes.@*METHODS@#The ventricular myocytes were isolated from the heart of neonatal (within 3 days) SD rats by enzyme digestion and cultured in the presence of 5-Brdu. After reaching confluence, the cultured ventricular myocytes were identified using immunofluorescence assay for -SA protein. The cells were then cultured in either normal (5 mmol/L) or high glucose (30 mmol/L) medium in the presence of ALDH2 agonist Alda-1, ALDH 2 inhibitor Daidzin, or Alda-1 and NFAT3 inhibitor (11R-VIVIT). Fluorescent probe and ELISA were used to detect intracellular Ca concentration and CaN content, respectively; ALDH2, CaN and NFAT3 protein expressions in the cells were detected using Western blotting.@*RESULTS@#Compared with cells cultured in normal glucose, the cells exposed to high glucose showed a significantly decreased expression of ALDH2 protein ( < 0.05) and increased expressions of CaN ( < 0.05) and NFAT3 proteins with also increased intracellular CaN and Ca concentrations ( < 0.01). Alda-1 treatment significantly lowered Ca concentration ( < 0.05), intracellular CaN content ( < 0.01), and CaN and NFAT3 protein expressions ( < 0.05), and increased ALDH2 protein expression ( < 0.05) in high glucose- exposed cells; Daidzin treatment significantly increased Ca concentration ( < 0.01) and intracellular CaN content ( < 0.05) in the exposed cells. Compared with Alda-1 alone, treatment of the high glucose-exposed cells with both Alda-1 and 11R-VIVIT did not produce significant changes in the expression of ALDH2 protein (>0.05) but significantly reduced the expression of NFAT3 protein ( < 0.05).@*CONCLUSIONS@#Mitochondrial ALDH2 protects neonatal rat cardiomyocytes against high glucose-induced injury possibly by negatively regulating Ca-CaN-NFAT3 signaling pathway.

The molecular mechanism for nuclear transport and its application / 대한해부학회지

Transportation between the cytoplasm and the nucleoplasm is critical for many physiological and pathophysiological processes including gene expression, signal transduction, and oncogenesis. So, the molecular mechanism for the transportation needs to be studied not only to understand cell physiological processes but also to develop new diagnostic and therapeutic targets. Recent progress in the research of the nuclear transportation (import and export) via nuclear pore complex and four important factors affecting nuclear transport (nucleoporins, Ran, karyopherins, and nuclear localization signals/nuclear export signals) will be discussed. Moreover, the clinical significance of nuclear transport and its application will be reviewed. This review will provide some critical insight for the molecular design of therapeutics which need to be targeted inside the nucleus.

Survive or thrive: tradeoff strategy for cellular senescence

Aging-dependent cellular behaviors toward extrinsic stress are characterized by the confined localization of certain molecules to either nuclear or perinuclear regions. Although most growth factors can activate downstream signaling in aging cells, they do not in fact have any impact on the cells because the signals cannot reach their genetic targets in the nucleus. For the same reason, varying apoptotic stress factors cannot stimulate the apoptotic pathway in senescent cells. Thus, the operation of a functional nuclear barrier in an aging-dependent manner has been investigated. To elucidate the mechanism for this process, the housekeeping transcription factor Sp1 was identified as a general regulator of nucleocytoplasmic trafficking (NCT) genes, including various nucleoporins, importins, exportins and Ran GTPase cycle-related genes. Interestingly, the posttranslational modification of Sp1 is readily influenced by extrinsic stress, including oxidative and metabolic stress. The decrease in SP1 O-GlcNAcylation under oxidative stress or during replicative senescence makes it susceptible to proteosomal degradation, resulting in defective NCT functions and leading to nuclear barrier formation. The operation of the nuclear barrier in aging provides a fundamental mechanism for cellular protection against stress and promotes survival at the expense of growth via stress-sensitive transcriptional control.

Interaction of Flightless I with Nup88 and Importin β / 生物工程学报

High expression of Fightless I (FLII) is associated to multiple tumors. Based on our previous study that FLII might be involved in the nuclear export, we assessed the possible interaction of FLII with the nuclear envelop associating proteins Importin β and Nup88. We first constructed GST-FLII, GST-LRR recombinant plasmids and transformed them into the Rosetta strain to produce GST-FLII, GST-LRR fusion protein. After purification of these proteins, GST-pull down, as well as co-immunoprecipitation, were used to test the interaction of FLII with Importin β and Nup88. FLII interacted with Importin β and Nup88, and FLII LRR domain is responsible for these interactions. Thus, FLII may play a role in nuclear export through interaction with Importin β and Nup88.

The First Korean Case of Childhood Acute Myeloid Leukemia with Inv(11)(p15q22)/NUP98-DDX10 Rearrangement: A Rare but Recurrent Genetic Abnormality

No abstract available.

2-DG enhances TRAIL-induced apoptosis of leukemia HL-60 cells / 中国实验血液学杂志

This study was purposed to investigate the effects of 2-deoxy-D-glucose (2-DG) on sensitizing HL-60 cells to tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-induced apoptosis and its possible mechanism. The proliferative inhibition of HL-60 cells treated with different concentrations of 2-DG and TRAIL was measured by MTT assay. The cells were treated with 2-DG, TRAIL, and 2-DG combined with TRAIL at the concentration < IC50 value, i.e. 10 mmol/L for 2-DG and 100 ng/ml for TRAIL. Apoptosis was analyzed by flow cytometry with PI staining; the expression of RIP1, GRP78, and PARP was analyzed by Western blot; the activity of caspase-3 was detected by special detection kit. The results showed that the combined treatment of HL-60 cells for 48 h induced an apoptotic rate of (45.1 ± 4.3)%, which was significantly higher than that of treated with 2-DG or TRAIL alone; at the same time, the combined treatment potentiated the expression of GRP78 and caspase-3 activity, and down-regulated the expression of RIP1. It is concluded that 2-DG can sensitize HL-60 cells to TRAIL-induced apoptosis, which may be correlated with excessive endoplasmic reticulum stress response, down-regulation of RIP1, and increase of caspase-3 activity.

The 2A protease of enterovirus 71 cleaves nup62 to inhibit nuclear transport / 病毒学报

To study the impact of the enterovirus 71(EV71) on the nuclear transport mechanism,The pGFP-NLS vector with nuclear location signal(NLS) was constructed, RD cells transfected by the pGFP-NLS vector were inoculated with the EV71 or cotransfected by EV71-2A vector. The results showed that GFP protein with NLS was expressed in the cytoplasm due to the inhibition of nuclear transport. In order to further study the mechanism of the EV71 to prevent nuclear transport,Nup62 was detected by Western blotting after RD cells were infected with EV71 or transfected by EV71-2A vector. The results showed that decreased expression of Nup62 could be detected after infection with EV71 and transfection by EV71-2A vector. This study demonstrates that the cleavage of Nup62 by EV71 2A protease may be the mechanism of nuclear transport inhibition.

Allgrove syndrome

Allgrove syndrome is a rare autosomal recessive disorder. It is also known as the 3A syndrome and characterised by the triad of achalasia, alacrima and adrenal insufficiency. The AAAS gene is encoded on chromosome 12q13. We report the case of a 23-year-old woman who presented at the hospital with adrenal crisis that was triggered by infection of the urinary system and gastrointestinal bleeding. She had a known diagnosis of achalasia for eight years, and ophthalmologic examination revealed alacrima. Based on our findings, the patient was diagnosed with Allgrove syndrome.

Expression of SET-NUP214 fusion gene in patients with T-cell acute lymphoblastic leukemia and its clinical significance / 中国实验血液学杂志

This study was aimed to investigate the occurrence and clinical significance of the SET-NUP214 fusion gene in patients with T-cell acute lymphoblastic leukemia (T-ALL), analyse clinical and biological characteristics in this disease. RT-PCR was used to detect the expression of SET-NUP214 fusion gene in 58 T-ALL cases. Interphase FISH and Array-CGH were used to detect the deletion of 9q34. Direct sequencing was applied to detect mutations of PHF6 and NOTCH1. The results showed that 6 out of 58 T-ALL cases (10.3%) were detected to have the SET-NUP214 fusion gene by RT-PCR. Besides T-lineage antigens, expression of CD13 and(or) CD33 were detected in all the 6 cases. Deletions of 9q34 were detected in 4 out of the 6 patients by FISH. Array-CGH results of 3 SET-NUP214 positive T-ALL patients confirmed that this fusion gene was resulted from a cryptic deletion of 9q34.11q34.13. PHF6 and NOTCH1 gene mutations were found in 4 and 5 out of 6 SET-NUP214 positive T-ALL patients, respectively. It is concluded that SET-NUP214 fusion gene is often resulted from del(9)(q34). PHF6 and NOTCH1 mutations may be potential leukemogenic event in SET-NUP214 fusion gene.

Gene rearrangement pattern of immunoglobulin and T-cell receptor (Ig/TR) and its clinical characteristics in children with SET-NUP214 fusion gene-positive leukemia/lymphoma / 中国实验血液学杂志

The purpose of this study was to analyze the gene rearrangement pattern of immunoglobulin and T-cell receptor (Ig/TR) and its clinical characteristics in three children with SET-NUP214 fusion gene positive leukemia/lymphoma. The transcript of SET-NUP214 fusion gene was detected by RT-nested PCR. The pattern of Ig/TR gene rearrangement was analyzed by using the BIOMED-2 multiplex PCR assays. Allelic-specific primers were designed for further monitoring the minimal residual disease (MRD). The results indicated that the fusion site located between exon 7 of SET and exon 18 of NUP214 at mRNA level in the three patients. The diagnoses were made as the mixed phenotype of acute leukemia (MPAL) for patients 1, acute T-lymphoblastic leukemia (T-ALL) for patients 2, and stage IV T-lymphoblastic lymphoma (T-LBL) for patients 3, respectively. Patient 1 responded to chemotherapy very poorly and relapsed at month 6 after hematopoietic stem cell transplantation. Patient 2 had high MRD (> 10(-2)) at the end of inducing remission therapy (day 33) which implied poor outcome, and died of toxic epidermal necrolysis and sequent serious infection. Patient 3 achieved hematological complete remission (CR) and MRD negative at day 15 and day 33 respectively. The duration of CR lasted for 30 months. Clonal TR gene rearrangements were detected in all the three patients. The rearrangements of TRD, TRG and TRB were found in patient 1 and 3. The rearrangements of TRD, TRB, IgH and IgK Kde were detected in patient 2. All the 6 TRB rearrangements detected were incomplete rearrangements, whereas 85.7% and 14.3% of the TRD, and TRG rearrangements were complete and incomplete, respectively. It is concluded that the transformation of SET-NUP214(+) leukemia/lymphoma cells may occur after the rearrangements of TRD and TRG and shortly after TRB rearrangement. The leukemia/lymphoma cells of patient 1 and 2 are more immature which may be related with poor outcome or response to chemotherapy.

Calcium regulation of nucleocytoplasmic transport

Bidirectional trafficking of macromolecules between the cytoplasm and the nucleus is mediated by the nuclear pore complexes (NPCs) embedded in the nuclear envelope (NE) of eukaryotic cell. The NPC functions as the sole pathway to allow for the passive diffusion of small molecules and the facilitated translocation of larger molecules. Evidence shows that these two transport modes and the conformation of NPC can be regulated by calcium stored in the lumen of nuclear envelope and endoplasmic reticulum. However, the mechanism of calcium regulation remains poorly understood. In this review, we integrate data on the observations of calciumregulated structure and function of the NPC over the past years. Furthermore, we highlight challenges in the measurements of dynamic conformational changes and transient transport kinetics in the NPC. Finally, an innovative imaging approach, single-molecule superresolution fluorescence microscopy, is introduced and expected to provide more insights into the mechanism of calcium-regulated nucleocytoplasmic transport.

Premature loss of permanent teeth in Allgrove [4A] syndrome in two related families

Allgrove syndrome is a rare autosomal recessive condition characterized by adrenal insufficiency, achalasia, alacrima and occasionally autonomic disturbances. Mutations in the AAAS gene, on chromosome 12q13 have been implicated as a cause of this disorder. We present various manifestations of this syndrome in two related families each with two affected siblings in which several members had symptoms including reduced tear production, mild developmental delay, achalasia, neurological disturbances and also premature loss of permanent teeth in two of them. The importance of this report is dental involvement [loss of permanent teeth] in Allgrove syndrome that has not been reported in literature

Tissue-specific expression and subcellular localization of ALADIN, the absence of which causes human triple A syndrome

Triple A syndrome is a rare genetic disorder caused by mutations in the achalasia-addisonianism-alacrima syndrome (AAAS) gene which encodes a tryptophan aspartic acid (WD) repeat-containing protein named alacrima-achalasia-adrenal insufficiency neurologic disorder (ALADIN). Northern blot analysis shows that the 2.1 kb AAAS mRNA is expressed in various tissues with stronger expression in testis and pancreas. We show that human ALADIN is a protein with an apparent molecular weight of 60 kDa, and expressed in the adrenal gland, pituitary gland and pancreas. Furthermore, biochemical analysis using anti-ALADIN antibody supports the previous finding of the localization of ALADIN in the nuclear membrane. The mutations S544G and S544X show that alteration of S544 residue affects correct targeting of ALADIN to the nuclear membrane.

Effects of gambogic acid on the regulation of nucleoporin Nup88 in HL-60 cells / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To investigate the effect of gambogic acid (GA) on cell proliferation and induction of apoptosis in HL-60 cells in vitro, as well as the regulation of nucleoporin Nup88 to explore the relationship between them.</p><p><b>METHODS</b>The effect of GA on the growth of HL-60 cells was determined by MTU assay. Apoptosis was detected with Hoechst 33258 staining and annexin-V FITC/PI double-labeled flow cytometry. The influence on cell cycle was studied by a propidium iodide method. Both flow cytometry (FCM) and RT-PCR techniques were applied to assess the expression of Nup88, whereas the localization of Nup88 was determined by confocal laser scanning microscopy.</p><p><b>RESULTS</b>GA presented striking inhibitory effect on proliferation of HL-60 cells in vitro and induction of apoptosis in a time- and dose-dependent manner. However, no obvious influence was found on the cell cycle in HL-60 cells. The IC50 value for 12 h was 1.797 micromol/L. 15.1% of HL-60 cells went apoptosis when treated with 0.4 micromol/L GA for 12 h. When the dose of GA was increased to 1.6 micromol/L, more than half of cells were apoptotic. On the other hand, the expression level of Nup88 was down-regulated in HL-60 cells induced by GA in a dose-dependent manner. The distribution of Nup88 was also changed from widely dispersed in both nucleus and cytoplasm to that only localized at the cytoplasmic side of nuclear membrane, occasionally in the cytoplasm sporadically.</p><p><b>CONCLUSION</b>GA exhibites remarkable inhibitory effect on cell proliferation in leukemic cells and inducing apoptosis in HL-60 cells in a cell cycle-independent manner, which might correspond to the regulation of the expression as well as the distribution of nucleoporin Nup88. It may become a new remedy for treatment for acute leukemia.</p>

Overexpression of CHIP in chronic myeloid leukemia K562 cells induces mitotic abnormality / 中国实验血液学杂志

This study was aimed to investigate the possible influence of a novel E3 ubiquitin ligase CHIP (carboxyl terminus of Hsc70/Hsp70-interacting protein) on biological characteristics of cancer cells. Stable overexpression models in CML K562 cells were established via lipofectamine-mediated wild type CHIP and its TPR or U-box deletion mutants gene transfection. Followed G418 pressure selection, K562-CHIP stable transfected cell clones were obtained by limited dilution. The proliferation status and cell cycle were observed by MTT assay and FACS. The expression of related proteins and morphological changes were detected by Western blot and Wright-Giemsa staining. The results showed that overexpression of wild type CHIP did not inhibit cell proliferation, but slightly increased cell ratio of G(2)/M phase. CHIP gene had no effect on the stability of BCR-ABL kinase protein. HDAC inhibitor FK228-induced BCR-ABL degradation did not enhanced by CHIP. Notably the enlarged cells and abnormal mitotic cells remarkably increased in K562 WT-CHIP cells, indicating that CHIP may involve in the regulation of mitotic process. It is concluded that wild type CHIP induces mitotic abnormity in K562 cells.