Two Likely Auto-Tetraploidization Events Shaped Kiwifruit Genome and Contributed to Establishment of the Actinidiaceae Family.

The genome of kiwifruit (Actinidia chinensis) was sequenced previously, the first in the Actinidiaceae family. It was shown to have been affected by polyploidization events, the nature of which has been elusive. Here, we performed a reanalysis of the genome and found clear evidence of 2 tetraploidization events, with one occurring ∼50-57 million years ago (Mya) and the other ∼18-20 Mya. Two subgenomes produced by each event have been under balanced fractionation. Moreover, genes were revealed to express in a balanced way between duplicated copies of chromosomes. Besides, lowered evolutionary rates of kiwifruit genes were observed. These findings could be explained by the likely auto-tetraploidization nature of the polyploidization events. Besides, we found that polyploidy contributed to the expansion of key functional genes, e.g., vitamin C biosynthesis genes. The present work also provided an important comparative genomics resource in the Actinidiaceae and related families.

Arsenic trioxide at conventional dosage does not aggravate hemorrhage in the first-line treatment of adult acute promyelocytic leukemia.

OBJECTIVES: The arsenic trioxide (ATO) plus all-trans retinoic acid (ATRA) therapy has demonstrated a tremendous success in the first-line treatment of acute promyelocytic leukemia (APL). Actually, early death (ED) is currently thought as a major challenge in APL. ATO has been reported to inhibit platelet function in vitro, and whether it increases the ED rate by exacerbating the hemorrhagic symptoms remains to be investigated. METHODS: Effects of ATO on platelet aggregation and adhesion were evaluated in vitro and in thirty-two complete remission (CR) and four newly diagnosed APL patients. Furthermore, concentrations of plasma total arsenic were monitored in APL patients via ICP-MS. RESULTS: The inhibition of platelet function, either aggregation or adhesion, did occur in vitro when the concentration of ATO reached 2 µmol/L. However, in CR APL patients receiving ATO with normal platelet count, the platelets responded normally when being activated and so did those in the newly diagnosed patients with thrombocytopenia. Our data further showed that the conventional dosage of ATO reached a plasma concentration substantially below the required concentration to inhibit platelets. CONCLUSIONS: In the first-line treatment of APL, the use of ATO is safe and effective and does not compromise the hemostatic potential that may eventually increase ED rate.

Mutations of Epigenetic Modifier Genes as a Poor Prognostic Factor in Acute Promyelocytic Leukemia Under Treatment With All-Trans Retinoic Acid and Arsenic Trioxide.

BACKGROUND: Acute promyelocytic leukemia (APL) is a model for synergistic target cancer therapy using all-trans retinoic acid (ATRA) and arsenic trioxide (ATO), which yields a very high 5-year overall survival (OS) rate of 85 to 90%. Nevertheless, about 15% of APL patients still get early death or relapse. We performed this study to address the possible impact of additional gene mutations on the outcome of APL. METHODS: We included a consecutive series of 266 cases as training group, and then validated the results in a testing group of 269 patients to investigate the potential prognostic gene mutations, including FLT3-ITD or -TKD, N-RAS, C-KIT, NPM1, CEPBA, WT1, ASXL1, DNMT3A, MLL (fusions and PTD), IDH1, IDH2 and TET2. RESULTS: More high-risk patients (50.4%) carried additional mutations, as compared with intermediate- and low-risk ones. The mutations of epigenetic modifier genes were associated with poor prognosis in terms of disease-free survival in both training (HR = 6.761, 95% CI 2.179-20.984; P = 0.001) and validation (HR = 4.026, 95% CI 1.089-14.878; P = 0.037) groups. Sanz risk stratification was associated with CR induction and OS. CONCLUSION: In an era of ATRA/ATO treatment, both molecular markers and clinical parameter based stratification systems should be used as prognostic factors for APL.

[A new artemisinin derivative SM1044 induces apoptosis of Kasumi-1 cells and its mechanism].

The aim of this study was to investigate the apoptosis-inducing effect of artemisinin derivative SM1044 on Kasumi-1 cells and its possible mechanism. Kasumi-1 cells were treated with different concentrations of SM1044, the cell viability was evaluated by MTT assay. Cell apoptosis and cell cycle progression were assessed by using flow cytometry with Annexin-V/PI double staining and flow cytometry with PI staining respectively. The expression of apoptosis-related proteins caspase 3, PARP and the fusion protein AML1-ETO were detected by Western blot. The results indicated that SM1044 inhibited cell growth of Kasumi-1 cells in time- and dose-dependent manners. After exposure of Kasumi-1 cells to 1 µmol/L SM1044 for 24 hours, the cell viability was decreased to 50%. IC(50) of SM1044 to Kasumi-1 cells at 48 hours was 0.17 ± 0.067 µmol/L. SM1044 induced cell apoptosis in a caspase-dependent manner, and the apoptotic rate of Kasumi-1 cells increased as SM1044 concentration increased. Flow cytometry with PI staining revealed that SM1044 induced cell cycle arrest, and the proportion of cells in G(0)/G(1) phase increased from 58.33 ± 4.46% to 71.75 ± 2.24% after exposure to 5 µmol/L SM1044 for 24 hours. Western blot showed that SM1044 increased the expression of apoptosis-related proteins cPARP and cleaved caspase 3 and also degraded the AML1-ETO fusion protein. It is concluded that SM1044 can inhibit the proliferation of Kasumi-1 cells, induce cell apoptosis which may be related to the increased level of cleaved PARP and cleaved caspase 3. SM1044 can also induce cell arrest in G(0)/G(1) phase. As the fusion protein AML1-ETO degrades obviously, it can be the potential target of SM1044 in Kasumi-1 cells.

[Mucosa advancement flap anoplasty in treatment of chronic anal fissures: a prospective, multicenter, randomized controlled trial].

BACKGROUND: Anal fissure is one of the most common anal-rectum diseases, and approximately 10 percent patients with chronic anal fissure ultimately receive surgery. Relieving postoperative pain and protecting functions of the sphincter are central issues for coloproctologists. OBJECTIVE: To evaluate the efficacy and safety of anoplasty in the treatment of chronic anal fissures. DESIGN, SETTING, PARTICIPANTS AND INTERVENTIONS: In this prospective, multicenter, randomized controlled trial, 120 adult patients with chronic anal fissure were referred from Department of Coloproctology of Yueyang Hospital of Integrated Traditional Chinese Medicine Affiliated to Shanghai University of Traditional Chinese Medicine, Shanghai Ninth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine and Shanghai Municipal Hospital of Traditional Chinese Medicine. The patients were enrolled from January 2009 to April 2010 and randomly divided into study (mucosa advancement flap anoplasty, abbreviated as anoplasty) group and control (fissurectomy) group. The two groups were assessed separately, and the main outcome measures were observed for 2 weeks, with a short-term follow-up for 6 weeks. MAIN OUTCOME MEASURES: Degree of pain, haemorrhage and anal canal pressure were observed and recorded preoperatively, and on the third day, the fourteenth day and the sixth week postoperatively. The wound healing time was also recorded. Surgical complications of the two groups were recorded and compared on the third day and the sixth week postoperatively. The curative effects associated with the surgery were analyzed on the fourteenth day and the sixth week after surgery and the therapeutic results were evaluated. RESULTS: Three patients were dropped out due to the early discharge from hospital and losing connection (1 in study group and 2 in control group). Overall the surgery showed that the anoplasty group had better results than the fissurectomy group in the curative effect on the sixth week after operation (P<0.05). Time of wound healing in the anoplasty group was (17.22 ± 4.41) d and was better than (21.24 ± 7.44) d of the fissurectomy group (P<0.05). Concerning the relief of wound pain, the anoplasty group achieved better results than the fissurectomy group at the third day, the fourteenth day and the sixth week after operation (P<0.05). Anoplasty reduced bleeding and had better efficacy than the fissurectomy at the third day and the fourteenth day after operation (P<0.05), however, there was no statistical difference at the sixth week after operation (P>0.05). There were no significant differences in relieving the anal canal pressure (P>0.05) and the surgical complications (dysuria, edema of anal margin, fever, infection, anal incontinence and anal deformation) between the two groups (P>0.05). None of the patients suffered postoperative complications by the sixth week after operation. Furthermore, there was no recurrence in either of the two groups at six weeks after operation. CONCLUSION: The results indicate that anoplasty for chronic anal fissures has advantages such as better therapeutic effects, less postoperative pain, a shorter healing time and no incidence of anal incontinence.

Long-term efficacy and safety of all-trans retinoic acid/arsenic trioxide-based therapy in newly diagnosed acute promyelocytic leukemia.

All-trans retinoic acid (ATRA)/arsenic trioxide (ATO) combination-based therapy has benefitted newly diagnosed acute promyelocytic leukemia (APL) in short-term studies, but the long-term efficacy and safety remained unclear. From April 2001, we have followed 85 patients administrated ATRA/ATO with a median follow-up of 70 months. Eighty patients (94.1%) entered complete remission (CR). Kaplan-Meier estimates of the 5-year event-free survival (EFS) and overall survival (OS) for all patients were 89.2% +/- 3.4% and 91.7% +/- 3.0%, respectively, and the 5-year relapse-free survival (RFS) and OS for patients who achieved CR (n = 80) were 94.8% +/- 2.5% and 97.4% +/- 1.8%, respectively. Upon ATRA/ATO, prognosis was not influenced by initial white blood cell count, distinct PML-RARalpha types, or FLT3 mutations. The toxicity profile was mild and reversible. No secondary carcinoma was observed, and 24 months after the last dose of ATRA/ATO, patients had urine arsenic concentrations well below the safety limit. These results demonstrate the high efficacy and minimal toxicity of ATRA/ATO treatment for newly diagnosed APL in long-term follow-up, suggesting a potential frontline therapy for de novo APL.

[cAMP analogue 8-CPT-cAMP inducing differentiation in the M2b subtype of acute myeloid leukemia cell line Kasumi-1].

This study was aimed to investigate the possible effects of cyclic adenosine monophosphate (cAMP) analogue 8-(4-chlorophenylthio) adenosine 3', 5'-cyclic monophosphate (8-CPT-cAMP) on the M(2b) subtype of acute myeloid leukemia (AML-M(2b)) cells. AML-M(2b) is characterized by the non-random chromosome translocation t (8; 21) (q22; q22), through which AML1 (acute myeloid leukemia 1) gene on chromosome 21 is fused with ETO (eight twenty-one) gene on chromosome 8, coding correspondent AML1-ETO fusion protein, which plays a crucial role in the leukemogenesis of AML-M(2b). The AML-M(2b) cell line Kasumi-1 cells were used as an in vitro model. The influences of 8-CPT-cAMP on the proliferation and differentiation of Kasumi-1 cells were evaluated according to cellular morphology, changes in cell surface antigen and cell cycle, as well as nitroblue-tetrazolium (NBT) assay. Meanwhile, semi-quantity RT-PCR and Western blot assay were used to detect the degradation of AML1-ETO fusion protein in Kasumi-1 cells before and after the treatment. The results showed that 8-CPT-cAMP (200 micromol/L) could significantly inhibit cell growth and induce differentiation of Kasumi-1 cells. However, it must be pointed out that 8-CPT-cAMP-induced differentiation in Kasumi-1 is not a typical terminal differentiation. Furthermore, 8-CPT-cAMP exerted little influence on the expression of AML1-ETO fusion gene and its product in Kasumi-1 cells. In conclusion, the 8-CPT-cAMP induced differentiation in Kasumi-1 cells. This results may provide experimental and theoretical basis for the breakthrough of differentiation-induced therapy extended to another leukemia.

Acute promyelocytic leukemia: from highly fatal to highly curable.

Acute promyelocytic leukemia (APL) is a distinct subtype of acute myeloid leukemia. Morphologically, it is identified as the M3 subtype of acute myeloid leukemia by the French-American-British classification and cytogenetically is characterized by a balanced reciprocal translocation between chromosomes 15 and 17, which results in the fusion between promyelocytic leukemia (PML) gene and retinoic acid receptor alpha (RARalpha). It seems that the disease is the most malignant form of acute leukemia with a severe bleeding tendency and a fatal course of only weeks. Chemotherapy (CT; daunorubicin, idarubicin and cytosine arabinoside) was the front-line treatment of APL with a complete remission (CR) rate of 75% to 80% in newly diagnosed patients. Despite all these progresses, the median duration of remission ranged from 11 to 25 months and only 35% to 45% of the patients could be cured by CT. Since the introduction of all-trans retinoic acid (ATRA) in the treatment and optimization of the ATRA-based regimens, the CR rate was raised up to 90% to 95% and 5-year disease free survival (DFS) to 74%. The use of arsenic trioxide (ATO) since early 1990s further improved the clinical outcome of refractory or relapsed as well as newly diagnosed APL. In this article, we review the history of introduction of ATRA and ATO into clinical use and the mechanistic studies in understanding this model of cancer targeted therapy.

[In vitro study of the effects of CDA-II combined with cAMP on apoptosis induction in retinoic acid resistant acute promyelocytic leukemia cells].

OBJECTIVE: To investigate the effects of CDA-II alone or combined with cAMP on the retinoic acid (RA)-resistant acute promyelocytic leukemia (APL) cells. METHODS: The RA-resistant cell line NB4-R2 was used as an in vitro model and treated with CDA-II alone or in combination with cAMP. Cell apoptosis was assessed by morphology observation, distribution of cellular DNA contents and sub-G1 cell population. The level of Bcl-2 was detected by flow cytometry, DNA "ladder" was detected by agarose-electrophoresis. RESULTS: CDA-II could induce NB4-R2 cell apoptosis through decreasing the level of cellular anti-apoptotic protein Bcl-2. cAMP could significantly enhance the role of CDA-II. Bcl-2 positive cell rates decreased to (15.1 +/- 4.8)% and (7.3 +/- 2.9)% in NB4-R2 cells treated with 1 mg/ml CDA-II plus 100 micromol/L cAMP for 48 h and 72 h, respectively. While 100 micromol/L of cAMP could decrease Bcl-2 positive NB4-R2 cells from (92.0 +/- 0.6)% to (75.3 +/- 2.0)%. CONCLUSIONS: CDA-II combined with cAMP could exert potent apoptotic effect on RA-resistant APL cells.

[Effects of resolving stagnation and promoting granulation therapy on expressions of Bax and Bcl-2 in granulation tissue of diabetic rats during wound healing].

OBJECTIVE: To study the effects of resolving stagnation and promoting granulation therapy on expressions of Bax and Bcl-2 in granulation tissue of diabetic rats during wound healing. METHODS: Seventy-two male SD diabetic rats with full-thickness skin lesion were randomly divided into 3 groups: SJHYR 1-treated group, SJHYR 2-treated group and normal saline (NS) control group. SJHYR 1 was prepared with Shengji Recipe (SJR, a compound traditional Chinese herbal medicine for promoting granulation) and Huayu Recipe (HYR, a compound traditional Chinese herbal medicine for resolving stagnation) at a ratio of 1:2, while SJHYR 2 was prepared with SJR and HYR at a ratio of 1:1. Immunohistochemical method was used to assess Bax and Bcl-2 protein levels in granulation tissue. RESULTS: SJHYR 1 could accelerate wound healing as compared with SJHYR 2 and NS (P<0.05). On the third day in experiment, Bax and Bcl-2 proteins were not found in any groups, but on the seventh and eleventh day in experiment, Bax and Bcl-2 proteins in SJHYR 1-treated group were much higher than those in the other two groups (P<0.05). CONCLUSION: SJR and HYR in different ratios may all have a role in regulating Bax and Bcl-2 expression in granulation tissue of diabetic rats during wound healing.

[Effects of arsenic trioxide and ATRA on PLZF-RARalpha-positive U937 leukemic cells].

AIM: To investigate effects of arsenic trioxide (As(2)O(3)) and alltrans retinoic acid (ATRA) on PLZF-RARalpha-positive cells. METHODS: PLZF-RARalpha-positive U937 cells (U937/PLZF) were used as an in vitro model. The change of cell morphology was observed by Wright-Giemsa staining. Cell growth and proliferation were detected by methyl thiazolyl tetrazolium(MTT) assay. Cell cycle distribution and expression of cell membrane surface differentiation-related antigens (such as CD11b, CD64 and CD14) were determined by flow cytometry assay. Expression of PLZF was analyzed by immunofluorescence. Functional differentiation was reflected by nitroblue tetrazolium(NBT) reduction ability and cytochemistry staining. RESULTS: While U937/PLZF cells were incubated in tetracycline-withdrawn medium, the expression of PLZF-RARalpha; protein increased. After treated with As(2)O(3) (0.5 micromol/L) and ATRA (1 mumol/L), U937/PLZF cells presented some changes such as decreased nuclear/cytoplasm ratio, and partial disappearance of nucleoli, suggesting a certain degree of morphological differentiation. The cell growth and proliferation were inhibited in a dose- and time-dependent manner. The proportion of cells in S phage was decreased and CD11b level was increased. The expression of PLZF relocated in treated cells. However, no significant difference in NBT assay and cytochemistry staining was documented with the combination therapy. CONCLUSION: The combination of As(2)O(3) with ATRA can cause a slight tendency to morphological differentiation but is insufficient to induce functional differentiation of PLZF-RARalpha positive U937 leukemia cells.

Mutant transcription factors and tyrosine kinases as therapeutic targets for leukemias: from acute promyelocytic leukemia to chronic myeloid leukemia and beyond.

Mutations in transcription factors (TFs) and protein tyrosine kinases (PTKs), which result in inhibition of differentiation/apoptosis or enhanced proliferative/survival advantage of hematopoietic stem/progenitor cells, are two classes of the most frequently detected genetic abnormalities in leukemias. The critical roles for mutant TFs and/or PTKs to play in leukemogenesis, and the absence of mutant TFs/PTKs in normal hematopoietic cells, suggest that the two types of aberrant molecules may serve as ideal therapeutic targets. The great success of all-trans retinoic acid (ATRA) and arsenic trioxide (ATO) in treating acute promyelocytic leukemia through modulation of the causative PML-RARalpha oncoprotein represents the first two paradigms of mutant TFs-targeting therapeutic strategies for leukemia. More recently, tyrosine kinase inhibitor STI-571/Imatinib mesylate/Gleevec in the treatment of Breakpoint Cluster Region-Abelson (BCR-ABL) positive leukemia elicits paradigm of mutant PTKs as ideal antileukemia targets. Thus to further improve clinical outcome of leukemia patients, elucidation of pathogenesis of leukemia, screening for oncoprotein-targeting small molecules, as well as rationally designed combination of drugs with potential synergy are of importance.

Treatment of acute promyelocytic leukaemia with all-trans retinoic acid and arsenic trioxide: a paradigm of synergistic molecular targeting therapy.

To turn a disease from highly fatal to highly curable is extremely difficult, especially when the disease is a type of cancer. However, we can gain some insight into how this can be done by looking back over the 50-year history of taming acute promyelocytic leukaemia (APL). APL is the M3 type of acute myeloid leukaemia characterized by an accumulation of abnormal promyelocytes in bone marrow, a severe bleeding tendency and the presence of the chromosomal translocation t(15;17) or variants. APL was considered the most fatal type of acute leukaemia five decades ago and the treatment of APL was a nightmare for physicians. Great efforts have been made by scientists worldwide to conquer this disease. The first use of chemotherapy (CT) was unsuccessful due to lack of supportive care and cytotoxic-agent-related exacerbated coagulopathy. The first breakthrough came from the use of anthracyclines which improved the complete remission (CR) rate, though the 5-year overall survival could only be attained in a small proportion of patients. A rational and intriguing hypothesis, to induce differentiation of APL cells rather than killing them, was raised in the 1970s. Laudably, the use of all-trans retinoic acid (ATRA) in treating APL resulted in terminal differentiation of APL cells and a 90-95% CR rate of patients, turning differentiation therapy in cancer treatment from hypothesis to practice. The combination of ATRA with CT further improved the 5-year overall survival. When arsenic trioxide (ATO) was used to treat relapsed APL not only the patients but also the ancient drug were revived. ATO exerts dose-dependent dual effects on APL cells: at low concentration, ATO induces partial differentiation, while at relatively high concentration, it triggers apoptosis. Of note, both ATRA and ATO trigger catabolism of the PML-RARalpha fusion protein which is the key player in APL leukaemogenesis generated from t(15;17), targeting the RARalpha (retinoic acid receptor alpha) or promyelocytic leukaemia (PML) moieties, respectively. Hence, in treating APL both ATRA and ATO represent paradigms for molecularly targeted therapy. At molecular level, ATRA and ATO synergistically modulate multiple downstream pathways/cascades. Strikingly, a clearance of PML-RARalpha transcript in an earlier and more thorough manner, and a higher quality remission and survival in newly diagnosed APL are achieved when ATRA is combined with ATO, as compared to either monotherapy, making APL a curable disease. Thus, the story of APL can serve as a model for the development of curative approaches for disease; it suggests that molecularly synergistic targeted therapies are powerful tools in cancer, and dissection of disease pathogenesis or anatomy of the cancer genome is critical in developing molecular target-based therapies.

Oridonin, a diterpenoid extracted from medicinal herbs, targets AML1-ETO fusion protein and shows potent antitumor activity with low adverse effects on t(8;21) leukemia in vitro and in vivo.

Studies have documented the potential antitumor activities of oridonin, a compound extracted from medicinal herbs. However, whether oridonin can be used in the selected setting of hematology/oncology remains obscure. Here, we reported that oridonin induced apoptosis of t(8;21) acute myeloid leukemic (AML) cells. Intriguingly, the t(8;21) product AML1-ETO (AE) fusion protein, which plays a critical role in leukemogenesis, was degraded with generation of a catabolic fragment, while the expression pattern of AE target genes investigated could be reprogrammed. The ectopic expression of AE enhanced the apoptotic effect of oridonin in U937 cells. Preincubation with caspase inhibitors blocked oridonin-triggered cleavage of AE, while substitution of Ala for Asp at residues 188 in ETO moiety of the fusion abrogated AE degradation. Furthermore, oridonin prolonged lifespan of C57 mice bearing truncated AE-expressing leukemic cells without suppression of bone marrow or reduction of body weight of animals, and exerted synergic effects while combined with cytosine arabinoside. Oridonin also inhibited tumor growth in nude mice inoculated with t(8;21)-harboring Kasumi-1 cells. These results suggest that oridonin may be a potential antileukemia agent that targets AE oncoprotein at residue D188 with low adverse effect, and may be helpful for the treatment of patients with t(8;21) AML.

Factor X Shanghai and disruption of translocation to the endoplasmic reticulum.

BACKGROUND AND OBJECTIVES: Most secreted proteins, including coagulation factor X (FX), are synthesized with a signal peptide, which is necessary for targeting the nascent polypeptide into the endoplasmic reticulum. Characterization of naturally occurring mutations may provide insights into the functional roles of the amino acids in the signal peptide. DESIGN AND METHODS: A 52-year old male patient with type I FX deficiency was studied. Mutations were searched for by FX gene (F10) sequencing. The wild-type and the mutant FX proteins were expressed in transfected cells and then immunological assays were performed. Pulse-chase experiments and cell-free expression studies were conducted to determine the cellular fate of the mutant FX molecules. RESULTS: The patient we studied was homozygous for a substitution of arginine for serine at codon -30 in the signal sequence of F10. Immunoassays detected low FX antigen levels in both the conditioned media and lysates of the cells expressing the mutant protein. Pulse-chase analysis showed that only trace amounts of the mutant FX protein were detectable in the conditioned media, and that the mutant molecules did not accumulate inside the cells either. The results of cell-free expression studies showed that although the transcription and translation of the mutant construct were normal, no post-translational processing, such as N-linked glycosylation, occurred in the presence of microsomes. INTERPRETATION AND CONCLUSIONS: These findings suggest that substitution of a neutral polar amino acid, serine by arginine, in the hydrophobic core of FX signal peptide severely impairs the ability of the protein to enter the endoplasmic reticulum and results in FX deficiency.

[Present status in studying immunotherapy for acute leukemia and its perspective--Editorial].

One of the important approaches for further prolonging remission duration and eradicating minimal residual disease in acute leukemia is immunotherapy. Four kinds of immunotherapy for acute leukemia are under investigation: (1) monoclonal antibodies, among them, Mylotarg (cytotoxic antibiotic calicheamicin linked to CD33 Mab) is given for the treatment of refractory or relapsed acute myeloid leukemia and molecular relapse in acute promyelocytic leukemia with good results, Campath-1H (antiCD52 Mab) is administered in the treatment of prolymphocytic leukemia and Rituximab (anti-CD20 Mab) in B-PLL with high complete remission rates. Other Mabs under preclinical and clinical trials include anti-IL-2 receptor Mab for the treatment of acute T lymphocytic leukemia, anti-220 kD Mab-6G7 for acute leukemias, recombinant immune toxin BL22 (anti-CD22) for hairy cell leukemia and Mabs labeled with radio-isotopes for different types of acute leukemias; (2) adoptive cellular immunotherapy using cytokine-induced killer cell, alloreactive NK cells, allogeneic or autologous leukemic-specific CD8(+) cytotoxic T lymphocytes, and other immune effector cells; (3) cytokines and other immune modulators comprising IL-2, IL-12, GM-CSF, CD40L, FLT-3L and thalidomide and its derivatives; (4) leukemia vaccines of several different formulations including antigen-specific, leukemia cell-based, leukemia antigen-pulsed dendritic cell (DC) and leukemia-derived DC vaccines, the latter two formulations are more attractive. In conclusion, up to now, the most effective example of immunotherapy in acute leukemia is provided by the administration of Mabs, and the majority of other approaches in immunotherapy for acute leukemia although promising, need further studies.

Biochemical activity and gene analysis of inherited protein C and antithrombin deficiency in two Chinese pedigrees.

BACKGROUND: We identified the gene mutations in two Chinese pedigree of type I hereditary protein C deficiency and type I hereditary antithrombin deficiency. METHODS: The plasma level of protein C activity (PC:A), protein C antigen (PC:Ag), protein S activity, antithrombin activity (AT:A) and antithrombin antigen (AT:Ag) of propositi and two family members were detected using ELISA and chromogenic assay, respectively. All exons and intron-exon boundaries of protein C gene and antithrombin gene were analyzed by direct sequencing of the corresponding amplified PCR products in DNA from the propositus. RESULTS: The plasma PC:A and PC:Ag of propositus 1 was 26% and 1.43 mg/dl, respectively. The PC:Ag and PC:A of his father were normal. The decreased PC:A level was seen in his mother and 4 of his maternal pedigree. PS:A and AT:A were all normal in pedigree 1 members. A C5498T heterozygous mutation in exon 3 of protein C gene, resulting in the substitution of Arg for Trp at the 15th amino acid, was identified in propositus 1 and 8 of his relatives. The plasma AT:A and AT:Ag of propositus 2 was 48.6% and 10.4 mg/dl, respectively. The reduced AT:A and AT:Ag levels were found in his father and 5 of paternal pedigree. PC:A, PC:Ag and PS:A were all in normal range. A heterozygous 13387-9G deletion in exon 6 of antithrombin gene was identified in propositus 2. This mutation introduced a frameshift and a premature stop at codon 426 and existed in 6 members of pedigree 2. CONCLUSION: The C5498T heterozygous mutation in exon 3 of protein C gene, first reported in China, leads to type I hereditary protein C deficiency. The 13387-9G deletion, a novel mutation, can cause antithrombin deficiency and thrombosis.

[Development of human myeloid leukemia-like phenotype in NUP98-PMX1 transgenic mice].

OBJECTIVE: In order to investigate the leukemogenic potential of NUP98-PMX1 fusion gene in vivo. METHODS: NUP98-PMX1 transgenic mice were generated, in which the fusion gene was driven by hCG promoter and expressed in myeloid cells at early stage of differentiation. Molecular cloning technology was used to construct NUP98-PMX1 transgenic plasmid. The genotype and phenotype of the NUP98-PMX1 transgenic mice were analyzed by PCR, RT-PCR, peripheral blood count (PBC), bone marrow (BM) cells morphology and pathological examination. RESULTS: NIH3T3 cells transfected with NUP98-PMX1 fusion gene grew faster, formed colonies in soft agar, and developed tumors in 10 inoculated nude mice. Among 8 disordered NUP98-PMX1 transgenic mice, 4 developed myeloid leukemia-like phenotype, including 3 resembling human chronic myeloid leukemia. CONCLUSION: NUP98-PMX1 has oncogenic activity and plays a crucial role in leukemogenesis.