In vitro antiproliferative activity of 2,3-dihydroxy-9,10-anthraquinone induced apoptosis against COLO320 cells through cytochrome c release caspase mediated pathway with PI3K/AKT and COX-2 inhibition

The present study investigated the anticancer activity of 2,3-dihydroxy-9,10-anthraquinone against different cancer cells such as MCF-7, COLO320, HepG-2, Skov-3, MOLM-14, NB-4, CEM, K562, Jurkat, HL-60, U937, IM-9 and Vero. 2,3-dihydroxy-9,10-anthraquinone showed good antiproliferative activity against COLO320 cells when compared to other tested cells. The cytotoxicity results showed 79.8% activity at the dose of 2.07 μM with IC50 value of 0.13 μM at 24 h in COLO320 cells. So we chose COLO320 cells for further anticancer studies. mRNA expression was confirmed by qPCR analysis using SYBR green method. Treatment with 2,3-dihydroxy-9,10-anthraquinone was found to trigger intrinsic apoptotic pathway as indicated by down regulation of Bcl-2, Bcl-xl; up regulation of Bim, Bax, Bad; release of cytochrome c and pro-caspases cleaving to caspases. Furthermore, 2,3-dihydroxy-9,10-anthraquinone stopped at G0/G1 phase with modulation in protein levels of cyclins. On the other hand PI3K/AKT signaling plays an important role in cell metabolism. We found that 2,3-dihydroxy-9,10-anthraquinone inhibits PI3K/AKT activity after treatment. Also, COX-2 enzyme plays a major role in colorectal cancer. Our results showed that the treatment significantly reduced COX-2 enzyme in COLO320 cells. These results indicated antiproliferative activity of 2,3-dihydroxy-9,10-anthraquinone involving apoptotic pathways, mitochondrial functions, cell cycle checkpoint and controlling the over expression genes during the colorectal cancer. Molecular docking studies showed that the compound bound stably to the active sites of Bcl-2, COX-2, PI3K and AKT. This is the first report of anticancer mechanism involving 2,3-dihydroxy-9,10-anthraquinone in COLO320 cells. The present results might provide helpful suggestions for the design of antitumor drugs toward colorectal cancer treatment.

Synthetic investigation on chirally pure Mannich derivatives of pseudophenylpropanolamine and their anticancer properties against HepG-2 cells with inhibition of JAK2/STAT3

In vitro and in vivo anticancer activity of compound 3a was proved as a novel blocker of JAK2/STAT3 signaling pathway and exerts both anti-proliferative and apoptotic activities in HepG-2 cells with xenograft mice model.

In vitro anticancer activity of methyl caffeate isolated from Solanum torvum Swartz. fruit

The present study was undertaken to investigate the anticancer activity of methyl caffeate isolated from Solanum torvum Swartz. fruit and to explore the molecular mechanisms of action in MCF-7 cells. Cytotoxic properties of hexane, ethyl acetate and methanol extracts were carried out against MCF-7 cells using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay. Ethyl acetate extract showed good cytototoxic activities compared to hexane and methanol extracts. Methyl caffeate was isolated from the ethyl acetate extract using column chromatography. Cytotoxic properties of methyl caffeate was investigated against MCF-7, A549, COLO320, HepG-2 and Vero cells. The compound showed potent cytotoxic properties against MCF-7 cells compared to A549, COLO320 and HepG-2 cells. Methyl caffeate significantly reduced cell proliferation and increased formation of fragmented DNA and apoptotic body in MCF-7 cells. Bcl-2, Bax, Bid, p53, caspase-3, PARP and cytochrome c release were detected by western blot analysis. The activities of caspases-3 and PARP gradually increased after the addition of isolated compound. Bcl-2 protein was down regulated; Bid and Bax were up regulated after the treatment with methyl caffeate. Molecular docking studies showed that the compound bound stably to the active sites of poly (ADP-ribose) polymerase-1 (PARP1), B cell CLL/lymphoma-2 (BCL-2), E3 ubiquitin-protein ligase (MDM2) and tubulin. The results strongly suggested that methyl caffeate induced apoptosis in MCF-7 cells via caspase activation through cytochrome c release from mitochondria.

Delayed hematopoietic recovery after auto-SCT in patients receiving arsenic trioxide-based therapy for acute promyelocytic leukemia: a multi-center analysis

A potential link between arsenic (ATO)-based therapy and delayed hematopoietic recovery after autologous hematopoietic SCT (HSCT) for acute promyelocytic leukemia (APL) has previously been reported. We retrospectively reviewed the clinical histories of 58 patients undergoing autologous HSCT for APL at 21 institutions in the United States and Japan. Thirty-three (56%) of the patients received ATO-based therapy prior to stem cell collection. Delayed neutrophil engraftment occurred in 10 patients (17%): 9 of the 10 patients (90%) received prior ATO (representing 27% of all ATO-treated patients), compared with 1 of the 10 patients (10%) not previously treated with ATO (representing 4% of all ATO-naïve patients; P<0.001). Compared with ATO-naïve patients, ATO-treated patients experienced significantly longer times to ANC recovery (median 12 days vs 9 days, P<0.001). In multivariate analysis, the only significant independent predictor of delayed neutrophil engraftment was prior treatment with ATO (hazard ratio 4.87; P<0.001). Of the available stem cell aliquots from APL patients, the median viable post-thaw CD34+ cell recovery was significantly lower than that of cryopreserved autologous stem cell products from patients with non-APL AML. Our findings suggest that ATO exposure prior to CD34+ cell harvest has deleterious effects on hematopoietic recovery after autologous HSCT.

HapMap SNP Scanner: an online program to mine SNPs responsible for cell phenotype

Minor histocompatibility (H) antigens are targets of graft-vs-host disease and graft-vs-tumor responses after human leukocyte antigen matched allogeneic hematopoietic stem cell transplantation. Recently, we reported a strategy for genetic mapping of linkage disequilibrium blocks that encoded novel minor H antigens using the large dataset from the International HapMap Project combined with conventional immunologic assays to assess recognition of HapMap B-lymphoid cell line by minor H antigen-specific T cells. In this study, we have constructed and provide an online interactive program and demonstrate its utility for searching for single-nucleotide polymorphisms (SNPs) responsible for minor H antigen generation. The website is available as 'HapMap SNP Scanner', and can incorporate T-cell recognition and other data with genotyping datasets from CEU, JPT, CHB, and YRI to provide a list of candidate SNPs that correlate with observed phenotypes. This method should substantially facilitate discovery of novel SNPs responsible for minor H antigens and be applicable for assaying of other specific cell phenotypes (e.g. drug sensitivity) to identify individuals who may benefit from SNP-based customized therapies.

High incidence of secondary failure of platelet recovery after autologous and syngeneic peripheral blood stem cell transplantation in acute promyelocytic leukemia

Secondary failure of platelet recovery (SFPR), which is a delayed decline in platelet count after primary recovery following myeloablative hematopoietic SCT, is a significant problem in allogeneic SCT. However, its clinical characteristics have not been well described in autologous SCT for acute myeloid leukemia. We reviewed 11 consecutive patients who had received autologous or syngeneic SCT for acute promyelocytic leukemia. Seven of 11 patients (64%) had SFPR, which is defined as a decline in the platelet count to less than 30,000/microl for more than 7 days. The median onset of SFPR was day 36 (range, 25-51 days) and the median duration of thrombocytopenia was 13 days (range, 4-25 days). Of nine patients who received busulfan-containing preparative regimens, seven (78%) had SFPR and one had delayed primary platelet count recovery. Neither patient who received cyclophosphamide and total body irradiation as preparative regimens had SFPR. The clinical courses of SFPR were transient and self-limited. SFPR was not associated with relapse of underlying diseases, graft failure or other fatal morbidities. The unexpectedly high prevalence and the characteristics of SFPR may provide additional information on management following autologous SCT for acute myeloid leukemia.

Lyn is an important component of the signal transduction pathway specific to FLT3/ITD and can be a therapeutic target in the treatment of AML with FLT3/ITD

Fms-like tyrosine kinase 3 (FLT3) is expressed in hematopoietic progenitor cells. An internal tandem duplication (ITD) of FLT3 (FLT3/ITD) is the most frequent mutation in human adult acute myeloid leukemia (AML). FLT3/ITD contributes to the constitutive activation of FLT3 itself and its downstream signal components, mitogen-activated protein kinase and signal transducers and activators of transcription 5 (STAT5), and enables interleukin (IL)-3-dependent cell lines to grow autonomously. In the present study, we showed the specific association of FLT3/ITD with Lyn, which led to the phosphorylation of Lyn in vivo. We also demonstrated that FLT3/ITD receptors displayed a higher affinity to bind to Lyn than wild-type FLT3 receptors in vitro and that this affinity was relative to the intensity of tyrosil phosphorylation of the receptor. Both treatment with small interfering RNA (siRNA) targeting Lyn and the Src family kinase inhibitor PP2 suppressed the IL-3-independent growth of FLT3/ITD-expressing 32D cells (FLT3/ITD-32D), reducing the constitutive phosphorylation of Lyn and STAT5. PP2 treatment of mice transplanted with FLT3/ITD-32D cells blocked the onset of tumors and decreased the size of established tumors. These results demonstrate that Lyn is an important component of the signal transduction pathway specific to FLT3/ITD and can be a therapeutic target in the treatment of AML with FLT3/ITD.

Different breakage-prone regions on chromosome 1 detected in t(11;14)-positive mantle cell lymphoma cell lines and multiple myeloma cell lines are associated with different tumor progession-related mechanisms

To better define secondary aberrations that occur in addition to translocation t(11;14)(q13;q32) in mantle cell lymphomas (MCL) and in multiple myelomas (MM), seven t(11;14)-positive MCL cell lines and four t(11;14)-positive MM cell lines were analysed by fluorescence R-banding and spectral karyotyping (SKY). Compared with published data obtained by G-banding, most chromosome aberrations were redefined or further specified. Furthermore, several additional chromosome aberrations were identified. Thus, these cytogenetically well defined t(11;14)-positive MCL and MM cell lines may be useful tools for the identification and characterization of genes that might be involved in the pathogenesis of MCL and MM, respectively. Since MCL and MM were found to have different alterations of chromosome 1, these were investigated in more detail by fluorescence in situ hybridization (FISH) and multicolor banding (MCB) analyses. The most frequently altered and deletion-prone loci in MCL cell lines were regions 1p31 and 1p21. In contrast, breakpoints in MM cell lines most often involved the heterochromatic regions 1p12-->p11, and the subcentromeric regions 1q12 and 1q21. These data are in accordance with previously published data of primary lymphomas. Our findings may indicate that different pathways of clonal evolution are involved in these morphologically distinct lymphomas harboring an identical primary chromosome aberration, t(11;14).

Increased risk for treatment-related mortality after bone marrow transplantation in GSTM1-positive recipients

Treatment-related mortality (TRM) is a major obstacle to successful allogeneic hematopoietic stem cell transplantation (HSCT). A variety of drugs are used in allogeneic HSCT, and a genetic polymorphism in metabolic enzymes could affect the metabolism of drugs and potentially influence TRM. Here, we focused attention on GSTM1 and GSTT1 enzymes, which metabolize chemotherapeutic agents, chemical carcinogens and by-products of oxidative stress and are absent from more than 50% of some populations. To assess the significance of homozygous GSTM1 and GSTT1 gene deletion in HSCT, we analyzed DNA from 373 patients with hematological disease and their HLA-identical unrelated bone marrow donors using PCR. Homozygous GSTM1 and GSTT1 gene deletions were observed in 56 and 45% of patients, respectively, and 57 and 46% of donors, respectively. There was no significant association between GSTT1 polymorphism and any outcome. However, a GSTM1-positive genotype in recipients was significantly associated with higher TRM and lower survival. These results suggest that a GSTM1-null genotype in recipients protects against TRM after allogeneic HSCT. Further studies are needed to elucidate a mechanism of increased risk for TRM in GSTM1-positive recipients.

Expression and methylation status of the FHIT gene in acute myeloid leukemia and myelodysplastic syndrome

To clarify the role of fragile histidine triad (FHIT) in hematological malignancies, we examined the methylation status and the expression level of the FHIT gene in myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML) cells in comparison with the methylation of the p15(INK4B) gene. The FHIT methylation was found in 13 of 94 (13.8%) AML and 22 of 40 (55.0%) MDS cases, but not in normal mononuclear cells (MNCs). Both the frequency and density of methylation increased in the advanced-stages MDS and the relapsed AML cases. Although FHIT and p15(INK4B) methylations were not correlated in MDS and AML, increased FHIT methylation at the relapse in AML was associated with p15(INK4B) methylation. The median expression level in AML was significantly higher than in normal MNCs, although the median expression level in those with methylation was significantly lower than in those without methylation. Furthermore, the methylation level at relapse was significantly higher than at diagnosis in AML. These results suggested that FHIT methylation was accumulated through the disease progression of MDS and AML, and the role of the FHIT gene as a tumor suppressor seemed different in AML and MDS.

Identification and frequency of a new HLA-A allele, A*030104

We here identified a novel HLA-A allele, A*030104, which was found in a Japanese family. The direct sequencing revealed that A*030104 was identical to A*030101 except for a nucleotide substitution of GAG to GAA at codon 63 without an amino acid replacement. The frequencies of A*030104 and A*0301 including A*030104 in Japanese population (n = 22,360) were approximately 0.013 and 0.40%, respectively.

Tacrolimus instead of cyclosporine used for prophylaxis against graft-versus-host disease improves outcome after hematopoietic stem cell transplantation from unrelated donors, but not from HLA-identical sibling donors: a nationwide survey conducted in Japan

Despite recent advances, graft-versus-host disease (GVHD) remains the main cause of treatment failure for patients undergoing allogeneic hematopoietic stem cell transplantation (HSCT). Tacrolimus (FK506) has been increasingly used in place of cyclosporine (CSP), and several studies have shown that FK506 reduces the incidence of acute GVHD more effectively than does CSP. However, no survival benefits have been demonstrated, and no established consensus exists on the choice of these immunosuppressive agents. To compare a CSP-based and an FK506-based regimen, we performed a large-scale retrospective study by using the data of 1935 patients who underwent HSCT from HLA-identical sibling donors (SIB-HSCT) and 777 patients who underwent HSCT from unrelated donors (UD-HSCT). For patients undergoing UD-HSCT, FK506 significantly reduced the risk of acute GVHD and treatment-related mortality (TRM) without an increase in relapse, thus improving overall survival (OS) (hazard ratio (HR): 2.20, 95% confidence interval (CI): 1.60-3.04, P<0.0001 for grade II-IV acute GVHD; HR: 1.81, 95% CI: 1.32-2.48, P=0.0003 for TRM; HR: 1.62, 95% CI: 1.23-2.14, P=0.0007 for OS). This superiority of FK506 was not observed in SIB-HSCT cases. These findings indicate that the use of FK506 instead of CSP for GVHD prophylaxis is beneficial for patients undergoing UD-HSCT.

Cytomegalovirus antigenemia and outcome of patients treated with pre-emptive ganciclovir: retrospective analysis of 241 consecutive patients undergoing allogeneic hematopoietic stem cell transplantation

CMV disease remains a major infectious complication after allogeneic hematopoietic stem cell transplantation (HSCT). To investigate the relationship between CMV antigenemia, treatment with ganciclovir (GCV), and outcome, we retrospectively analyzed 241 consecutive patients at risk for CMV infection who underwent allogeneic HSCT. Antigenemia-guided pre-emptive strategy with GCV was used for all patients. CMV antigenemia developed in 169 patients (70.1%), and CMV disease in 18 patients (7.5%). Multivariate analysis showed that acute GVHD (grades II-IV) was the only risk factor for developing antigenemia, and acute GVHD and advanced age for CMV disease. GCV use, as well as acute GVHD and advanced age, significantly increased the risk for bacterial and fungal infection after engraftment. Those who developed CMV antigenemia had a poorer outcome than those who did not (log-rank, P=0.0269), although the development of CMV disease worsened the outcome with only borderline significance (log-rank, P=0.0526). In conclusion, detection of antigenemia proved to be a poor prognostic factor for HSCT patients, which may be attributed to a combination of factors, including CMV disease itself, the effect of treatment, and a host status that allows for reactivation of CMV. Optimal pre-emptive strategy needs to be determined.

Allogeneic myeloablative transplantation for patients aged 50 years and over

Allogeneic hematopoietic stem cell transplantation (HSCT) has been performed mainly for young patients due to concern about the high incidence of treatment-related mortality (TRM). Recent advances to reduce TRM by using peripheral blood stem cells or nonmyeloablative conditioning regimens have increased the age limit for this procedure, and correctly identifying the indication for transplant is essential for older patients. In this study, we analyzed data from 398 patients aged 50 or over selected from 5147 patients, who received conventional allogeneic HSCT (c-HSCT). Patients aged 50 or older showed inferior outcomes for TRM and overall survival (OS). Mulitivariate analyses confirmed that an age of 50 or over was an independent risk factor for TRM (P<0.0001) and OS (P<0.0001). Among patients aged 50 or older, increasing age remained an adverse factor for OS (P=0.0213). Regimens including total-body irradiation (TBI) correlated with a higher risk of TRM and a lower OS for older patients (P=0.0095 and 0.0303, respectively). These findings indicate that allogeneic c-HSCT should be offered to patients over 50 years only if the increased risk of TRM is acceptable, and that a non-TBI regimen is preferable when the transplant is performed.

TEL-Syk fusion constitutively activates PI3-K/Akt, MAPK and JAK2-independent STAT5 signal pathways

We previously reported the fusion of the TEL gene to the Syk gene in myelodysplastic syndrome with t(9;12)(q22;p12). TEL-Syk fusion transformed interleukin-3 (IL-3)-dependent murine hematopoietic cell line BaF3 to growth factor independence. Here, we investigate the intracellular signal transduction of the stable transfectants. TEL-Syk fusion protein was associated with the p85 subunit of phosphatidyl inositol 3 kinase (PI3-K) followed by the activation of Akt in the absence of IL-3. Vav, phospholipase C-gamma2 and mitogen-activated protein kinase (MAPK) were also constitutively activated. TEL-Syk also activated the signal transducer and activator of transcription 5 (STAT5) in the absence of Janus kinase 2 activation. None of these kinases were phosphorylated in the BaF3 cells transfected with TELDeltaPNT-Syk in which the oligomerization domain of TEL was deleted. Inhibitor analysis showed that the MAPK pathway was important in TEL-Syk-mediated cell proliferation. The immunofluorescence technique revealed that the TEL-Syk fusion protein was located in the cytoplasm. These data suggest that TEL-Syk fusion protein in the cytoplasm leads to the constitutive activation of PI3-K/Akt, MAPK and STAT5 signal pathways, which are closely involved in IL-3-independent cell proliferation of BaF3 cells.

Sustained activation of c-jun-terminal kinase (JNK) is closely related to arsenic trioxide-induced apoptosis in an acute myeloid leukemia (M2)-derived cell line, NKM-1

High concentrations (greater than 5 microM) of arsenic trioxide (As(2)O(3)) have been reported to be able to induce apoptosis in several malignant cells. We explored cell lines in which apoptosis was induced with a therapeutic concentration (1-2 microM) of As(2)O(3), and found that 1 microM of As(2)O(3) induced apoptosis in the NKM-1 cell line, which was established from a patient with acute myeloid leukemia (M2). Apoptosis induced by 1 microM of As(2)O(3) in NKM-1 cells was accompanied by an increased cellular content of H(2)O(2), a decreased mitochondrial membrane potential (Deltapsim), and activation of caspase-3. C-Jun-terminal kinase (JNK) was activated only in NKM-1 cells and arsenic-sensitive NB4 cells, but not in arsenic-insensitive HL-60 cells. Activation of JNK in NKM-1 was sustained from 6 to 24 h after As(2)O(3) treatment, and preceded changes in cellular H(2)O(2), Deltapsim, and caspase-3 activation. Moreover, addition of a JNK inhibitor reduced the percentage of apoptotic cells after the As(2)O(3) treatment. Taken together, in the M2 cell line NKM-1, 1 microM of As(2)O(3) induced sustained activation of JNK and apoptosis. This finding may provide a basis to select a subgroup other than acute promyelocytic leukemia, which can benefit from As(2)O(3) treatment.

The percentage of myeloperoxidase-positive blast cells is a strong independent prognostic factor in acute myeloid leukemia, even in the patients with normal karyotype

To examine whether the percentage of myeloperoxidase (MPO)-positive blast cells is useful as a prognostic factor for acute myeloid leukemia (AML), cytochemical analysis of MPO was performed in 491 patients who were registered to the Japan Adult Leukemia Study Group-AML92 study. Patients were divided into two using the percentage of MPO-positive blast (high [>or=50%] and low (<50%)). Complete remission rates were 85.4% in the former and 64.1% in the latter (P=0.001). The overall survival (OS) and the disease-free survival (DFS) were significantly better in the high MPO group (48.3 vs 18.7% for OS, and 36.3 vs 20.1% for DFS, P<0.001, respectively). Multivariate analysis showed that both karyotype and the percentage of MPO-positive blast cells were equally important prognostic factors. The high MPO group still showed a better survival even when restricted to the intermediate chromosomal risk group or the patients with normal karyotype (P<0.001). The OS of patients with normal karyotype in the high MPO group was almost equal with that of the favorable chromosomal risk group. The percentage of MPO-positive blast cells is a simple and highly significant prognostic factor for AML patients, and especially useful to stratify patients with normal karyotype.

Nutritional therapy of chronic hepatitis by whey protein (non-heated)

In an open study the clinical efficacy of milk serum (whey) protein (Immunocal; cysteine content: 7.6-fold higher than that of casein) isolated from fresh milk and purified without heating was evaluated in 25 patients with chronic hepatitis B or C. Immunocal (12 g as protein) food (mousse) was given twice a day, in the morning and evening, for 12 weeks (test period). Casein (12 g as protein) food (mousse) was similarly given for two weeks prior to the start of the supplement with Immunocal food (induction period) and for four weeks after the end of the supplement with Immunocal food (follow-up period). Serum alanine aminotransferase (ALT) activity was reduced, and plasma glutathione (GSH) levels increased in six and five of eight patients with chronic hepatitis B, respectively, 12 weeks after the start of the supplement with Immunocal food. Serum lipid peroxide levels significantly decreased, and interleukin (IL)-2 levels and natural killer (NK) activity significantly increased. However, there were no significant Immunocal-related changes in 17 patients with chronic hepatitis C. These findings suggest that the long-term supplement with Immunocal alone may be effective for improving liver dysfunctions in patients with chronic hepatitis B.

Novel synthesized trimannose conjugate induces endocytosis and expression of immunostimulatory molecules in monocytic leukemia cells

Macrophage mannose receptor (MMR) recognizes the pattern of carbohydrates exposed on microorganisms and mediates endocytosis in macrophages. We have synthesized glycoconjugate cationic polymers carrying 3,6-branched alpha-D-mannoside, a trimannose conjugate (TMC) with a high affinity for mannose-specific lectins. Culture with 10 microM TMC for 6 hours induced adhesion and aggregation in NKM-1, a human myelomonocytic leukemia cell line. TMC also stimulated the accumulation of fluorescein isothiocyanate (FITC)-dextran (FITC-DX). This accumulation seemed to be mediated by endocytosis via MMR because mannan, which specifically binds to MMR, inhibited FITC-DX accumulation. Expression of CD14, adhesion molecules, and costimulatory molecules was induced for 24 hours in NKM-1 and in fresh leukemia blasts from 4 patients with acute myeloid leukemia (AML) M4 and M5 subtypes (French-American-British classification). To clarify the binding mechanism, we compared mannose conjugates and a monomer of mannose regarding their effects on endocytosis and enhancement of CD14 and CD86 expression. A polymer of monomannose clusters with a lower affinity for lectins slightly stimulated exdocytosis, whereas a monomer of trimannose had no effect. These findings suggest that concatenation between MMR and TMC may play an important role in the activation of monocytic leukemia cells. TMC may become a good candidate to target MMRs of leukemia cells.

Acute promyelocytic leukemia with apparently normal karyotype: molecular findings and response to all-trans retinoic acid

Acute promyelocytic leukemia (APL) is specifically associated with a reciprocal translocation, t(15; 17)(q22; q21), leading to the formation of a fusion of the retinoic acid receptor-alpha (RARA) gene and the promyelocytic leukemia (PML) gene. However, there are several reports describing APL cases lacking the t(15; 17). Many such cases are those bearing variant translocations involving chromosomes 15 or 17, and those with no chromosomal aberrations have rarely been reported. We have studied a patient with APL showing an apparently normal karyotype which was confirmed by spectral karyotyping (SKY). A submicroscopic PML-RARA fusion was identified by reverse transcriptase-polymerase chain reaction (RT-PCR) and fluorescent in situ hybridization (FISH). All-trans retinoic acid (ATRA) was effective as the initial therapy for remission induction and as the reinduction therapy after a relapse. The present study shows the key role of the fusion of PML-RARA in the responsiveness to ATRA as well as in the leukemogenesis of APL.

Constitutive kinase activation of the TEL-Syk fusion gene in myelodysplastic syndrome with t(9;12)(q22;p12)

The TEL gene on 12p12-13 is a target for a number of translocations associated with various hematological malignancies. The fusion of the TEL gene to the Syk gene in a patient with myelodysplastic syndrome (MDS) with t(9;12)(q22;p12) is reported. Southern blot analysis of patient bone marrow cells with TEL and Syk gene probes detected rearranged fragments. Anchored polymerase chain reaction identified the Syk gene, a nonreceptor tyrosine kinase, on 9q22 fused downstream of TEL exon 5. The TEL gene was fused in-frame to Syk and produced a fusion protein that was constitutively phosphorylated in tyrosine with dimerization that was mediated by the helix-loop-helix domain of TEL. A TEL-Syk fusion product transformed the murine hematopoietic cell line BaF3 to interleukin-3 growth factor independence. TEL-Syk is a novel transforming protein and leads to the transformation of hematopoietic cells. These data implicate that the rearranged Syk gene is involved in the pathogenesis of hematopoietic malignancies.

Novel gene delivery systems: complexes of fusigenic polymer-modified liposomes and lipoplexes

We have previously developed the succinylated poly(glycidol)-modified liposome which becomes fusigenic under weakly acidic condition. In this report, we describe that complexation of this pH-sensitive, fusigenic liposome with a lipoplex consisting of 3beta-(N-(N',N'-dimethylaminoethane) carbamoyl)cholesterol, dioleoylphosphatidylethanolamine and plasmid DNA gives efficient gene delivery systems. In this study, we prepared the complexes, which are termed SucPG-complexes, with a positively or negatively charged surface by mixing the lipoplex with varying amounts of the SucPG-modified liposomes. The positively charged SucPG-complexes either bearing or not bearing a cell-specific ligand, transferrin, could transfect HeLa cells efficiently. In contrast, the negatively charged complexes hardly transfected the cells when transferrin was not conjugated to them. However, the negatively charged SucPG complexes bearing transferrin exhibited high transfection ability against HeLa and K562 cells, indicating that this gene delivery was achieved through their binding to the cellular receptors. These transferrin-attached, negatively charged complexes retained the high transfection ability in the presence of serum. Thus, this negatively charged complex may be useful as nonviral vectors in vivo.

Protection of xeno-hepatocytes from complement-mediated cytolysis by transduction with homologous restriction factor 20 gene using retroviral vector

Xeno-hepatocyte transplantation has the possibility to substitute for clinical liver transplantation in certain restricted hepatic diseases such as inherited metabolic disorders. To overcome human complement-dependent cytotoxicity on xeno-hepatocytes, the effectiveness of ex vivo transfer with the homologous restriction factor 20 (HRF20, CD59) gene was examined on primary-cultured xeno-hepatocytes using a retroviral vector. Primary-cultured rat hepatocytes transduced with HRF20 cDNA expressed HRF20 antigen by flow cytometric analysis and showed the integration of HRF20 cDNA to the genomic DNA by the polymerase chain reaction. The viability of rat hepatocytes incubated with 50% human serum was decreased due to complement-dependent cytotoxicity, whereas that of the transfectant was significantly protected (77.2+/-9.4 vs. 97.8+/-5.2%, p < 0.01). It was concluded that primary-cultured xeno-hepatocytes transduced with HRF20 cDNA using a retroviral vector could escape complement-dependent cytolysis by human serum.

No significant association between HA-1 incompatibility and incidence of acute graft-versus-host disease after HLA-identical sibling bone marrow transplantation in Japanese patients

We retrospectively examined HA-1 typing with polymerase chain reaction using sequence-specific primers in 120 samples from 60 HLA-A2-positive Japanese bone marrow transplantation recipients who received short-term methotrexate and cyclosporin A for graft-versus-host disease (GVHD) prophylaxis and their HLA-identical sibling donors. HA-1-incompatible pairs were observed in 22% of the samples. The probability of developing acute GVHD (grade II to IV) in HA-1-incompatible and -compatible patients was 0% and 19%, respectively (P = .10). In a comparison between HA-1-incompatible and -compatible patients with standard-risk leukemia, in whom age, patient/donor sex, and use of a total body irradiation-containing regimen were equivalent, the probability of developing acute GVHD (grade II to IV) was 0% and 10%, respectively (P = .38). No evidence of recurrent leukemia was observed in the HA-1-incompatible patients with standard-risk leukemia, compared with 37% in HA-1-compatible patients (P = .11). In conclusion, HA-1 incompatibility may not be a risk factor for grade II to IV acute GVHD in Japanese patients who receive methotrexate and cyclosporin A and undergo bone marrow transplantation from HLA-identical sibling donors.

Aberrant expression of HLA-G antigen in interferon gamma-stimulated acute myelogenous leukaemia

We have analysed the expression of HLA-G in 40 leukaemia samples of various subtypes [seven cases of acute lymphoblastic leukaemia (ALL), 28 cases of acute myelogenous leukaemia (AML), three cases of chronic myelogenous leukaemia (CML) and two cases of chronic lymphocytic leukaemia (CLL)] by flow cytometry using HLA-G-specific monoclonal antibody. No leukaemia samples expressed HLA-G without incubation with interferon (IFN)-gamma. However, six out of 28 (21%) AML samples expressed HLA-G upon incubation with IFN-gamma. These six samples derived from one out of seven M2, two out of eight M4 and three out of five M5. The results indicated that AML cells, especially myelomonocytic leukaemia samples, are capable of expressing the HLA-G molecule.

[The current status and future applications of gene therapy and immunogene therapy for malignant lymphoma]

The present therapy for malignant lymphoma including stem cell transplantation, has been greatly developed. However, treatments still remain ineffective for many patients. Gene therapy is providing new strategies for the treatments of malignant lymphoma. There are three major approaches; 1) killing the tumor cell itself by introducing anti-sense genes against oncogene, tumor suppressor genes or drug-sensitive genes. 2) modifying the immune response by introducing genes that will trigger anti-tumor response or tumor specific genes to antigen presenting cell. 3) decreasing the sensitivity of hemopoietic cells by introducing drug resistance genes. We describe here the current and future applications of gene therapy for malignant lymphoma.

Conjugation of plasmid DNAs with lactose via diazocoupling enhances resistance to restriction enzymes and acquires binding affinity to galactose-specific lectin

Oligosaccharide-plasmid DNA conjugates were synthesized simply and effectively via the diazocoupling method. Plasmids (pUC19, pTRI-beta-actin, and pEGFP-C1) were treated with an N-beta-lactoside-substituted diazonium salt to yield diazocoupling products with degree of substitutions of 2.5-3.1 mol% of overall nucleobases. The lactose-pUC19 conjugate was found to resist restriction enzymes more strongly than the nonconjugated plasmid DNA and to acquire a strong binding affinity to galactose-specific lectin RCA(120). The diazocoupling modification of pTRI-beta-actin plasmid DNA little influenced in vitro transcription with T7 RNA polymerase. When lactose-pEGFP-C1 conjugate was transfected to baby hamster kidney (BHK) cells by means of cationic lipids, transduced gene was expressed in BHK cells similarly with the nonconjugated pEGFP-C1. The modification of plasmid DNA with carbohydrate enhanced the resistance to restriction enzymes and developed a strong binding affinity to galactose-specific lectin.

Inhibitory effect on the establishment of hepatic metastasis by transduction of the tissue plasminogen activator gene to murine colon cancer

Hepatic metastasis is a major factor in limiting the prognosis of patients with colon carcinoma. Recent investigations indicate a correlation between plasminogen activator profiles and hepatic metastasis. We examined the effectiveness of tissue plasminogen activator (tPA) gene therapy using a hepatic metastasis model of murine colon carcinoma. Murine colon carcinoma Colon 26 cells transduced with an MFGtPA retroviral vector (Colon 26/tPA) or an MFGLacZ retroviral vector (Colon 26/LacZ) were injected into the liver via the superior mesenteric vein of BALB/c mice, whose survival rates were checked daily. The mean survival rate of mice with hepatic metastasis induced by Colon 26/LacZ was 23.1 days, whereas that of mice with Colon 26/tPA was >100 days. The in vitro proliferation of Colon 26/tPA was comparable with that of Colon 26/LacZ, and antitumor immunity to wild-type Colon 26 cells was not induced after an intrahepatic injection of Colon 26/tPA. We suggest that transduction of the tPA gene to murine colon cancer is useful against the establishment of hepatic metastasis.

CD4- and CD56-positive T-cell line, MTA, established from natural killer-like T-cell leukemia/lymphoma

We have established a T-cell line, MTA, from the peripheral blasts of a patient with natural killer (NK)-like T-cell leukemia/lymphoma. The MTA cell displays a T-cell and NK-cell phenotype (CD2+, CD3+, CD4+, CD56+) identical to freshly isolated leukemic blasts from the patient. This cell line shows clonal T-cell receptor rearrangement and a distinguishable character by light microscopy with May-Grünwald Giemsa staining. G-banding analysis showed that the MTA cells had a karyotype of 94(4N), XXXX, add (1) (p36), del (5) (q14q23), add (17) (p11), add (19) (q13). However, unlike NK malignancy, we could not show a direct pathogenic role for Epstein-Barr virus (EBV) with EBV-encoded small RNA and polymerase chain reaction analysis. The MTA cell line is a novel cell line with which to study NK-like T-cell ontogenecity.

Successful culture and sustainability in vivo of gene-modified human oral mucosal epithelium

Human oral mucosal cells are an attractive site for tissue engineering because they are the most accessible cells in the body and easy to manipulate in vitro. They thus have possibilities for targeting by somatic gene therapy. We examined the efficiency of retrovirus-mediated gene transfer and the construction of mucosal epithelium in vivo. Human oral mucosal cells were transduced with a retroviral vector carrying the lacZ gene at high efficiency and constructed epithelium after G418 selection with 3T3 cells in vitro. The cultured oral mucosal epithelium membrane was then grafted onto immunodeficient mice. Beta-Gal expression was detected histochemically in vivo 5 weeks after grafting. Furthermore, we transduced factor IX cDNA into the mucosal epithelium membrane, and it was then transplanted into nude mice. Between 0.6 and 1.8 ng of human factor IX per milliliter was found in mouse plasma, and the production was continued for 23 days in vivo. These results confirmed that the oral mucosal epithelium is an ideal target tissue for gene therapy or tissue engineering.

Gene transfer with cationic lipid into human hepatocellular carcinoma in nude mice

BACKGROUND/AIMS

Using a cationic lipid, gene transfection into the tumor of a human hepatocellular carcinoma model in nude mice was attempted in order to explore the possibility of its use in gene therapy.

METHODOLOGY

A DNA-lipid complex was made by combining the cationic lipid distearyldimethyl ammonium bromide (DDAB) with pCMV sPORT expressing the reporter gene LacZ. The expression of this complex was first investigated in vitro against the human hepatocellular carcinoma cell line Li7HM. It was then injected directly into a hepatocellular carcinoma model tumor created by implanting Li7HM into the liver of BALB/c nu/nu mice, and the expression of LacZ was histologically evaluated.

RESULTS

LacZ gene was expressed in Li7HM in vitro with the optimized DNA-lipid complex. Cell toxicity was not a problem. Expression of LacZ was also seen in the mouse hepatocellular model tumor into which the complex had been injected, indicating successful gene transfection with this method.

CONCLUSIONS

Direct injection of a DNA-lipid complex into a mouse hepatocellular carcinoma model tumor is a safe and simple method of gene transfection, proving this to be a viable method of transfer for use in gene therapy.

Immune response of post-transplant peripheral lymphocytes against the patient pre-B cell line, NAGL-1

We have established a pre-B acute lymphoblastic leukemia (ALL) cell line, NAGL-1, from the bone marrow of a patient diagnosed with pre-B ALL. The patient has been disease-free for the 4 years since allogeneic bone marrow transplantation from her HLA-genotypically identical sister. NAGL-1 showed a pre-B cell phenotype (CD19+, CD10+, c mu+, s mu-) mostly identical to freshly isolated leukemic cells from the patient. This cell line strongly expressed HLA class I and HLA-DR molecules, as well as the costimulatory molecules CD54, CD40, and CD86. Cytotoxic T-lymphocyte (CTL) lines were generated by stimulating the donor-derived peripheral blood mononuclear cells with either irradiated leukemic cells or NAGL-1. Both CTL lines showed specific lysis against NAGL-1 in 51Cr release assays. Lytic activity was partially inhibited by anti-CD8 and anti-HLA class I monoclonal antibodies. Treatment of NAGL-1 with TNF-alpha increased its susceptibility to the CTL line. One CD8+ T cell clone derived from the CTL line killed both the patient phytohemagglutinin (PHA) blasts and NAGL-1 but not the donor PHA blasts, suggesting that the clone recognized the patient-specific minor antigen presented on both PHA blasts and NAGL-1. Utilization of leukemic cell lines could be a useful model for the development of CTL lines and clones for immunological study and potential immunotherapy.

Feasibility of double-expression retroviral vector using complement regulatory factor gene

The donor source of vascular endothelial cells for hybrid blood vessels seeded with genetically engineered endothelial cells is generally considered to be autologous. The purpose of this study was to determine whether porcine endothelial cells transduced with double-expression retroviral vector using complement-resistant gene could be substituted for autologous endothelial cells. Decay-accelerating factor (DAF) and tissue plasminogen activator (tPA) cDNA were inserted into retroviral vector with homologous restriction factor 20 cDNA as a complement regulatory factor gene. Porcine aortic endothelial cells were transduced with these double-expression retroviral vectors, followed by the complement-dependent selection. Porcine endothelial cells transduced withdouble-expression retroviral vectors showed a high gene expression of both DAF and tPA. Complement-dependent cytotoxicity and adherence of U937 were significantly inhibited by the transduction of double-expression vectors with complement regulatory factor gene. Double-expression retroviral vector using complement regulatory factor gene was efficacious in substituting porcine endothelial cells for the autologous endothelial cells.

Semliki Forest virus-based DNA expression vector: transient protein production followed by cell death

We have constructed a novel DNA expression vector based on Semliki Forest virus (SFV). SFV produces non-structural proteins (nsPs) which replicate genomic RNA and amplify the mRNA encoding the structural proteins of SFV. A recombinant cDNA genome of SFV, in which the SFV structural genes were replaced by a polylinker cassette to allow for insertion of heterologous DNA, was placed under the control of a cytomegalovirus immediate-early enhancer/promoter with a polyadenylation signal. Transfection of mammalian cells with this SFV-based plasmid vector, pSFV3-CMV-lacZ-pA, resulted in transient high-level expression of a beta-galactosidase reporter gene. The expression level of beta-galactosidase from pSFV3-CMVlacZ-pA was more than 20-fold higher than that obtained from the plasmid with deleted nsPs genes, pSFV3A5976-lacZ, demonstrating that the nsPs genes were essential for the high level of expression. Substantial beta-galactosidase activity was detected in the medium of pSFV3-CMV-lacZ-pA-transfected cells, suggesting that the overproduction of beta-galactosidase caused cell death and release of the protein into the medium. We have demonstrated a high-level expression of the exogenous beta-galactosidase gene from pSFV3-CMV-lacZ-pA constructed using an SFV replication system.

Bystander tumoricidal effect and gap junctional communication in lung cancer cell lines

Tumor cells expressing the herpes simplex virus-thymidine kinase (HSV-tk) gene become sensitive to ganciclovir (GCV), and the phenomenon by which tumor cells surrounding the HSV-tk expressing cells also become sensitive to GCV is known as the "bystander effect." The purpose of this study was to investigate the bystander effect in human lung-cancer cell lines, and the role of gap-junctional intercellular communication as the mechanism responsible for it. Gap-junctional intercellular communication was measured both with a dye-transfer assay involving single-cell microinjection of Lucifer Yellow and with a PKH26/calcein-AM double-dye-transfer assay. Significant bystander tumoricidal effect was observed in lung-cancer cell lines when cultured cells contained only 10% HSV-tk expressing cells. This was also observed to occur with cell lines of different origin or from different species. Although gap-junctional intercellular communication characterized by rapid transfer of Lucifer Yellow was not observed, we did detect gap-junctional communication marked by the slow transfer of calcein-AM in lung-cancer cell lines. However, neither an inhibitor (1-octanol) nor an enhancer (all trans-retinoic acid [ATRA]) of gap-junctional communication affected the extent of the bystander effect. These findings suggest that low levels of gap-junctional communication may be efficient for producing the bystander effect in lung-cancer cells, or that other mechanisms may underlie this effect. Although gap-junctional communication may play an important role in generating the bystander effect in tumor cells expressing the HSV-tk gene, further knowledge of the mechanism of this effect may help improve the treatment of lung cancer with an HSV-tk system.

Establishment of complement-resistant retroviral vector by homologous restriction factor 20 gene

Homologous restriction factor 20 (HRF20, CD59) is one of the complement regulatory factors. In this study, the complement-resistant retroviral vector, which possesses the HRF20 gene as a selection gene, was constructed and examined. The virus-producing cell, transduced with complement-resistant retroviral vector, was established after complement-dependent selection. NIH3T3 and PK15 cells transduced with this virus-producing cell were successfully selected by complement-dependent selection, which showed significant expression of the HRF20 antigen. In addition, these cells, transduced with tissue plasminogen activator (tPA) cDNA using complement-resistant retroviral vector, expressed tPA antigen after complement-dependent selection. These findings suggest that complement-resistant retroviral vector can be used for the double transduction of HRF20, as well as other genes.

Recombinant adeno-associated virus-mediated gene transfer into human leukemia cell lines

Adeno-associated virus (AAV)-based vector is a promising gene transfer vehicle by virtue of the characteristics of wild-type AAV:tropism to a wide range of human tissues and locus-specific integration at chromosome 19q13.3. To elucidate the nature of the recombinant AAV (rAAV), transduction of neomycin phosphotransferase enzyme gene (NeoR gene) into seven human leukemia cell lines was performed. Transduction efficiencies were assessed by colony formation assay and limiting dilution assay. The results suggested that both assays are comparable. Transduction efficiencies of the NeoR gene into K-562, MEG-O1, Raji, MOLT-3, HL-60, U937 and NKM-1 at a multiplicity of infection (MOI) of 0.1 were 0.27, 0.25, 0.015, 0.009, < 0.0025 and < 0.0025%, respectively. After purification and concentration of rAAV, 27% efficiency was observed in K562 at an MOI of 7 and a linear relationship between MOI and efficiency was confirmed, suggesting that this system may be useful for gene transduction into leukemia cells. Integration of the NeoR gene into the host genome was detected by Southern blotting analysis, which showed various sizes of digested fragments. A fluorescent in situ hybridization (FISH) study was carried out on 11 clones, in all of which the NeoR gene was integrated out of chromosome 19q13.3. In five of the clones, whole chromosome painting probes revealed that the integration sites were chromosomes 1q, 2q, 2q, 11p, 12p and 13q.

Analysis of prognostic factors in newly diagnosed acute promyelocytic leukemia treated with all-trans retinoic acid and chemotherapy. Japan Adult Leukemia Study Group

PURPOSE

We conducted a multicenter study of differentiation therapy with all-trans retinoic acid (ATRA) followed by intensive chemotherapy in patients with newly diagnosed acute promyelocytic leukemia (APL) and analyzed the prognostic factors for predicting complete remission (CR), event-free survival (EFS), and disease-free survival (DFS).

PATIENTS AND METHODS

All patients received ATRA until CR. If patients had an initial leukocyte count greater than 3.0 x 10(9)/L, they received daunorubicin (DNR) and behenoyl cytarabine (BHAC). During therapy, if patients showed blast and promyelocyte counts greater than 1.0 x 10(9)/L, they received additional DNR and BHAC. After achieving CR, patients received three courses of consolidation and six courses of maintenance/intensification chemotherapy.

RESULTS

Of 198 registered, 196 were assessable (age range, 15 to 86 years; median, 46) and 173 (88%) achieved CR. Multivariate analysis showed that no or minor purpura at diagnosis (P = .0046) and age less than 30 years (P = .0076) were favorable factors for achievement of CR. Predicted 4-year overall survival and EFS rates were 74% and 54%, respectively, and the 4-year predicted DFS rate for 173 CR patients was 62%. Multivariate analysis showed that age less than 30 years (P = .0003) and initial leukocyte count less than 10 x 10(9)/L (P = .0296) were prognostic factors for longer EFS, and initial leukocyte count less than 10.0 x 10(9)/L was a sole significant prognostic factor for longer DFS (P = .0001).

CONCLUSION

Our results show that age, hemorrhagic diathesis, and initial leukocyte count are prognostic factors for APL treated with ATRA followed by intensive chemotherapy.

Fusion of the platelet-derived growth factor receptor beta to a novel gene CEV14 in acute myelogenous leukemia after clonal evolution

Chromosomal translocations involving band 5q31-35 occur in several hematologic disorders. A clone with a t(5; 14)(q33; q32) translocation appeared at the relapse phase in a patient with acute myelogenous leukemia who exhibited a sole chromosomal translocation, t(7; 11), at initial diagnosis. After the appearance of this clone, the leukemia progressed with marked eosinophilia, and combination chemotherapy was ineffective. Southern blot analysis showed a rearrangement of the platelet-derived growth factor receptor beta (PDGFRbeta) gene at 5q33 which was not observed at initial diagnosis. This translocation resulted in a chimeric transcript fusing the PDGFRbeta gene on 5q33 with a novel gene, CEV14, located at 14q32. Expression of the 5' region of the PDGFRbeta cDNA, upstream of the breakpoint, was not detected. However, the 3' region of PDGFRbeta, which was transcribed as part of the CEV14-PDGFRbeta fusion gene, was detected. A partial cDNA for a novel gene, CEV14, includes a leucine zipper motif and putative thyroid hormone receptor interacting domain and is expressed in a wide range of tissues. The expression of a CEV14-PDGFRbeta fusion gene in association with aggressive leukemia progression suggests that this protein has oncogenic potential.