High expression of N-acetylglucosaminyltransferase IVa promotes invasion of choriocarcinoma.

BACKGROUND: Gestational trophoblastic diseases (GTDs) are related to trophoblasts, and human chorionic gonadotropin (hCG) is secreted by GTDs as well as normal placentas. However, the asparagine-linked sugar chains on hCG contain abnormal biantennary structures in invasive mole and choriocarcinoma, but not normal pregnancy or hydatidiform mole. N-acetylglucosaminyltransferase-IV (GnT-IV) catalyses ß1,4-N-acetylglucosamine branching on asparagine-linked oligosaccharides, which are consistent with the abnormal sugar chain structures on hCG. METHODS: We investigated GnT-IVa expression in GTDs and placentas by immunohistochemistry, western blot, and RT-PCR. We assessed the effects of GnT-IVa knockdown in choriocarcinoma cells in vitro and in vivo. RESULTS: The GnT-IVa was highly expressed in trophoblasts of invasive mole and choriocarcinoma, and moderately in extravillous trophoblasts during the first trimester, but not in hydatidiform mole or other normal trophoblasts. The GnT-IVa knockdown in choriocarcinoma cells significantly reduced migration and invasive capacities, and suppressed cellular adhesion to extracellular matrix proteins. The extent of ß1,4-N-acetylglucosamine branching on ß1 integrin was greatly reduced by GnT-IVa knockdown, although the expression of ß1 integrin was not changed. In vivo studies further demonstrated that GnT-IVa knockdown suppressed tumour engraftment and growth. CONCLUSION: These findings suggest that GnT-IVa is involved in regulating invasion of choriocarcinoma through modifications of the oligosaccharide chains of ß1 integrin.

The prostaglandin E2 EP1 receptor mediates pain perception and regulates blood pressure.

The lipid mediator prostaglandin E2 (PGE2) has diverse biological activity in a variety of tissues. Four different receptor subtypes (EP1-4) mediate these wide-ranging effects. The EP-receptor subtypes differ in tissue distribution, ligand-binding affinity, and coupling to intracellular signaling pathways. To identify the physiological roles for one of these receptors, the EP1 receptor, we generated EP1-deficient (EP1-/-) mice using homologous recombination in embryonic stem cells derived from the DBA/1lacJ strain of mice. The EP1-/- mice are healthy and fertile, without any overt physical defects. However, their pain-sensitivity responses, tested in two acute prostaglandin-dependent models, were reduced by approximately 50%. This reduction in the perception of pain was virtually identical to that achieved through pharmacological inhibition of prostaglandin synthesis in wild-type mice using a cyclooxygenase inhibitor. In addition, systolic blood pressure is significantly reduced in EP1 receptor-deficient mice and accompanied by increased renin-angiotensin activity, especially in males, suggesting a role for this receptor in cardiovascular homeostasis. Thus, the EP1 receptor for PGE2 plays a direct role in mediating algesia and in regulation of blood pressure.

Oncogenic effects of evolutionarily conserved noncoding RNA ECONEXIN on gliomagenesis.

Accumulating studies have demonstrated the importance of long noncoding RNAs (lncRNAs) during oncogenic transformation. However, because most lncRNAs are currently uncharacterized, the identification of novel oncogenic lncRNAs is difficult. Given that intergenic lncRNA have substantially less sequence conservation patterns than protein-coding genes across species, evolutionary conserved intergenic lncRNAs are likely to be functional. The current study identified a novel intergenic lncRNA, LINC00461 (ECONEXIN) using a combined approach consisting of searching lncRNAs by evolutionary conservation and validating their expression in a glioma mouse model. ECONEXIN was the most highly conserved intergenic lncRNA containing 83.0% homology with the mouse ortholog (C130071C03Rik) for a region over 2500 bp in length within its exon 3. Expressions of ECONEXIN and C130071C03Rik were significantly upregulated in both human and mouse glioma tissues. Moreover, the expression of C130071C03Rik was upregulated even in precancerous conditions and markedly increased during glioma progression. Functional analysis of ECONEXIN in glioma cell lines, U87 and U251, showed it was dominantly located in the cytoplasm and interacted with miR-411-5p via two binding sites within ECONEXIN. Inhibition of ECONEXIN upregulated miR-411-5p together with the downregulation of its target, Topoisomerase 2 alpha (TOP2A), in glioma cell lines, resulting in decreased cell proliferation. Our data demonstrated that ECONEXIN is a potential oncogene that regulates TOP2A by sponging miR-411-5p in glioma. In addition, our investigative approaches to identify conserved lncRNA and their molecular characterization by validation in mouse tumor models may be useful to functionally annotate novel lncRNAs, especially cancer-associated lncRNAs.

Efficacy of gemtuzumab ozogamicin on ATRA- and arsenic-resistant acute promyelocytic leukemia (APL) cells.

Acute promyelocytic leukemia (APL) cells express a considerable level of CD33, which is a target of gemtuzumab ozogamicin (GO), and a significantly lower level of P-glycoprotein (P-gp). In this study, we examined whether GO was effective on all-trans retinoic acid (ATRA)- or arsenic trioxide (ATO)-resistant APL cells. Cells used were an APL cell line in which P-gp was undetectable (NB4), ATRA-resistant NB4 (NB4/RA), NB4 and NB4/RA that had been transfected with MDR-1 cDNA (NB4/MDR and NB4/RA/MDR, respectively), ATO-resistant NB4 (NB4/As) and blast cells from eight patients with clinically ATRA-resistant APL including two patients with ATRA- and ATO-resistant APL. The efficacy of GO was analyzed by (3)H-thymidine incorporation, the dye exclusion test and cell cycle distribution. GO suppressed the growth of NB4, NB4/RA and NB4/As cells in a dose-dependent manner. GO increased the percentage of hypodiploid cells significantly in NB4, NB4/RA and NB4/As cells, and by a limited degree in NB4/MDR and NB4/RA/MDR cells. Similar results were obtained using blast cells from the patients with APL. GO is effective against ATRA- or ATO-resistant APL cells that do not express P-gp, and the mechanism of resistance to GO is not related to the mechanism of resistance to ATRA or ATO in APL cells. Leukemia (2005) 19, 1306-1311. doi:10.1038/sj.leu.2403807; published online 26 May 2005.

Serum thrombopoietin levels in patients correlate inversely with platelet counts during chemotherapy-induced thrombocytopenia.

We studied serum thrombopoietin (TPO) levels and circulating numbers of platelet during five courses of myelosuppressive post-remission chemotherapy in three patients with acute leukemia in complete remission. Serum TPO levels were measured by a newly developed and sensitive sandwich enzyme-linked immunosorbent assay. In all courses, serum TPO levels changed reciprocally with the platelet counts. When platelets were transfused into patients near the time of platelet nadir, the TPO levels dropped temporarily, while platelet counts temporarily increased. In addition, platelets obtained after transfusion in a thrombocytopenic patient showed lower binding to biotinylated TPO than donor platelets prior to the transfusion. The finding indicated that the TPO receptors were saturated with endogenous TPO of the patient with a high serum TPO level. These results suggest that the platelet mass directly regulates serum TPO levels by receptor-mediated absorption and is one of the major regulators of serum TPO levels in humans.

Reduced effect of gemtuzumab ozogamicin (CMA-676) on P-glycoprotein and/or CD34-positive leukemia cells and its restoration by multidrug resistance modifiers.

Gemtuzumab ozogamicin (CMA-676), a calicheamicin-conjugated humanized anti-CD33 mouse monoclonal antibody, has recently been introduced clinically as a promising drug for the treatment of patients with acute myeloid leukemia (AML), more than 90% of which express CD33 antigen. However, our recent study suggested that CMA-676 was excreted by a multi- drug-resistance (MDR) mechanism in P-glycoprotein (P-gp)-expressing leukemia cell lines. We analyzed the in vitro effects of CMA-676 on leukemia cells from 27 AML patients in relation to the amount of P-gp, MDR-associated protein 1 (MRP1), CD33 and CD34, using a multi-laser-equipped flow cytometer. The cytocidal effect of CMA-676, estimated by the amount of hypodiploid portion on cell cycle, was inversely related to the amount of P-gp estimated by MRK16 monoclonal antibody (P = 0.004), and to the P-gp function assessed by intracellular rhodamine-123 accumulation in the presence of PSC833 or MS209 as a MDR modifier (P = 0.0004 and P = 0.002, respectively). In addition, these MDR modifiers reversed CMA-676 resistance in P-gp-expressing CD33(+) leukemia cells (P = 0.001 with PSC833 and P = 0.0007 with MS209). In CD33(+) AML cells from 13 patients, CMA-676 was less effective on CD33(+)CD34(+) than CD33(+)CD34(-) cells (P = 0.002). PSC833 partially restored the effect of CMA-676 in CD33(+)CD34(+) cells. These results suggest that the combined use of CMA-676 and a MDR modifier will be more effective on CD33(+) AML with P-gp-related MDR.

Calicheamicin-conjugated humanized anti-CD33 monoclonal antibody (gemtuzumab zogamicin, CMA-676) shows cytocidal effect on CD33-positive leukemia cell lines, but is inactive on P-glycoprotein-expressing sublines.

Calicheamicin-conjugated humanized anti-CD33 mouse monoclonal antibody, CMA-676, has recently been introduced to clinics as a promising drug to treat patients with acute myeloid leukemia (AML) in relapse. However, the mechanism of action of CMA-676 has not been well elucidated. The cytotoxic effect of CMA-676 on HL60, NOMO-1, NB4, NKM-1, K562, Daudi, and the multidrug-resistant sublines, NOMO-1/ADR and NB4/MDR, was investigated by cell cycle distribution and morphology. These studies were done by a video-microscopic system, DNA fragmentation, dye exclusion and 3H-thymidine uptake after analysis of CD33, CD34, P-glycoprotein (P-gp), multidrug resistance (MDR)-associated protein and lung-related protein on these cells. A dose-dependent, selective cytotoxic effect of CMA-676 was observed in cell lines that expressed CD33, and was dependent on the amount of CD33 and the proliferative speed of the cells. Sensitive cells were temporally arrested at the G2/M phase before undergoing morphological changes. CMA-676 is not effective on P-gp-expressing multidrug-resistant sublines compared with parental cell lines. MDR modifiers, MS209 and PSC833, restored the cytotoxic effect of CMA-676 in P-gp-expressing sublines. CMA-676 is a promising agent in the treatment of patients with AML that expresses CD33. The combined use of CMA-676 and MDR modifiers may increase the selective cytotoxic effect in multidrug-resistant AML.

Extensive cytogenetic studies of clonality following interferon-alpha therapy in chronic myeloid leukemia occurring in monosomic cells in a patient with Turner syndrome mosaic.

In a 27-year-old female with Turner syndrome mosaic, Philadelphia (Ph) chromosome-positive chronic myeloid leukemia (CML) occurred only in the monosomic cells (45, Xc). Extensive cytogenetic studies, including triple-color fluorescence in situ hybridization (FISH), revealed that Ph-positive monosomic cells (45, Xc), Ph-negative monosomic cells and normal diploid cells (46, XX) were present in her bone marrow at diagnosis. After successful interferon therapy, the non-leukemia cells expanded and reconstituted normal hematopoiesis resulting in complete cytogenetic response, following the selective suppression of the monosomic Ph-positive leukemia clone. The ratio of Xc to XX cells in bone marrow cells was significantly increased to that in skin fibroblasts. Moreover, the ratio of Ph-positive cells to Ph-negative cells was found to be significantly different between karyotyping and FISH. Studies of this quite unique case not only confirmed the clonality of CML, effectiveness of interferon-alpha and X chromosome imbalance among different tissues, but also demonstrated a discrepant increase of the BCR/ABL-positive clone in CML. The latter supports the hypothesis that reduced programmed cell death may be the primary mechanism responsible for the expansion of the leukemia clone in CML. Our study verifies the importance of extensive analysis of a neoplastic disease in patients with a constitutional chromosomal abnormality.

Simple and reliably sensitive diagnosis and monitoring of Philadelphia chromosome-positive cells in chronic myeloid leukemia by interphase fluorescence in situ hybridization of peripheral blood cells.

Philadelphia (Ph) chromosome or the bcr/abl fusion gene is the hallmark of chronic myeloid leukemia (CML) and serves as a prognostic marker during its treatment. Its detection has been primarily done by karyotype analysis of bone marrow cells. The major limitation of the karyotypic technique is an absolute need for metaphases, often difficult to obtain in an appropriate number in patients under therapy. Fluorescence in situ hybridization (FISH) is a sensitive and quantitative method to detect the bcr/abl fusion gene in cells in both metaphase and interphase. Using M-bcr and abl probes, we performed the interphase FISH in the peripheral blood of 30 healthy volunteers and in 20 hematologically normal bone marrow samples. False-positive cells were detected in 2.7 +/- 0.7% (mean +/- standard deviation) and 2.3 +/- 0.7% among 500 cells, respectively. Then we tested 31 patients with CML at various stages of disease on 50 occasions. Although there was a good correlation between the percentage of FISH-positive cells in the peripheral blood and that in the bone marrow (r = 0.977), between the percentage of FISH-positive cells in the peripheral blood and that of Ph chromosome in the bone marrow (r = 0.841), and between the percentage of FISH-positive cells and that of Ph chromosome in the bone marrow (r = 0.933), the limits of agreement in each group were not small, and thus the peripheral blood FISH test can not be interpreted as the same method with conventional karyotyping. Additionally, we could easily rule out CML in 15 individuals with leukocytosis without performing bone marrow aspiration. The present study indicates that FISH analysis in the peripheral blood is a simple and reliably sensitive test for the detection and quantitative monitoring of the M-bcr/abl fusion gene in CML in routine clinical practice, although this can not entirely replace karyotype analysis of bone marrow cells.

In vitro IL-12 treatment of peripheral blood mononuclear cells from patients with leukemia or myelodysplastic syndromes: increase in cytotoxicity and reduction in WT1 gene expression.

Interleukin-12 (IL-12) has potent antitumor activities. We examined whether IL-12 enhanced the cytotoxicity of peripheral blood mononuclear cells (PBMNC) and decreased leukemia cells in 30 patients with leukemia or myelodysplastic syndromes (MDS): 12 acute myeloid leukemia (AML) (five in complete remission (CR) and seven in non-CR); six chronic myeloid leukemia (CML); and 12 MDS (three refractory anemia (RA), eight RA with excess of blasts and one chronic myelomonocytic leukemia). PBMNC from patients and five healthy volunteers were cultured at 5 x 10(5)/ml parallel with or without 100 units/ml of IL-12 for 3 days. Cytotoxicity of PBMNC against K562 cells was assessed by flow cytometry. To quantify the amount of leukemia cells, WT1 mRNA was measured by competitive reverse transcription polymerase chain reaction (RT-PCR), since WT1 mRNA is considered as a marker of minimal residual disease (MRD) in leukemia or MDS. The cytotoxicity of non-IL-12-treated PBMNC of 30 patients was 13.4+/-9.3% at the effector to target (E:T) ratio of 20:1, and significantly lower than that of normal subjects (25.7+/-8.4%). The cytotoxicity increased to 30.6+/-17.9% in the IL-12-treated PBMNC. WT1 mRNA in PBMNC of five healthy volunteers was less than 10(3) copies/microg of total RNA. Following the 3-day IL-12 treatment, mean WT1 mRNA of PBMNC was reduced from 10(4.8) to 10(4.2) copies/microg of total RNA in six CML patients, from 10(5.4) to 10(4.8) copies/microg in 12 MDS patients and from 10(5.0) to 10(4.2) copies/microg in five AML patients in CR, but not reduced in five of seven AML in non-CR. These results showed that IL-12 significantly enhanced PBMNC cytotoxicity and decreased the quantity of leukemia cells in PBMNC of most patients with MDS, CML and AML in CR. IL-12 might be of considerable benefit in the elimination of MRD in patients with hematological malignancies.

Arsenic trioxide therapy for relapsed or refractory Japanese patients with acute promyelocytic leukemia: need for careful electrocardiogram monitoring.

Recent studies have shown that arsenic trioxide (As(2)O(3)) can induce complete remission in patients with acute promyelocytic leukemia (APL). We tested the efficacy and safety of As(2)O(3) for the treatment of patients with APL who had relapsed from or become refractory to all-trans retinoic acid (ATRA) and conventional chemotherapy in a prospective study. As(2)O(3) at a dose of 0.15 mg/kg was administered until the date of bone marrow remission to a maximum of 60 days. In patients who achieved complete remission (CR), one additional course of As(2)O(3) was administered using the same dose for 25 days. Of 14 patients, 11 (78%) achieved CR. Six of 10 patients who achieved CR showed disappearance of PML-RARalpha transcript by RT-PCR assay. The duration of As(2)O(3)-induced CR ranged from 4 to 22 months (median, 8 months) at a median follow-up of 17 months. Adverse events included 13 electrocardiogram abnormalities (13 QTc prolongation, eight ventricular premature contraction, four nonsustained ventricular tachycardia and two paroxysmal supraventricular tachycardia), seven nausea and vomiting, four pruritus, three peripheral neuropathy, three fluid retention and one APL differentiation syndrome. Four patients received antiarrhythmic agents. Hyperleukocytosis developed in five patients and in three cytotoxic drugs were necessary. Other adverse events were relatively mild. As(2)O(3) treatment is effective and relatively safe in relapsed or refectory patients with APL. Cardiac toxicities in patients with QTc prolongation should be carefully monitored.

miR-615-5p is epigenetically inactivated and functions as a tumor suppressor in pancreatic ductal adenocarcinoma.

Pancreatic ductal adenocarcinoma (PDAC) is a highly invasive cancer with a poor prognosis. Although microRNA (miRNA) transcripts have a crucial role in carcinogenesis and development, little information is known regarding the aberrant DNA methylation of miRNAs in PDAC. Using methylated DNA immunoprecipitation-chip analysis, we found that miR-615-5p was hypermethylated in its putative promoter region, which silenced its expression in PDAC cell lines. In addition, the overexpression of miR-615-5p in pancreatic cancer cells suppressed cell proliferation, migration and invasion. Insulin-like growth factor 2 (IGF2) is an imprinted gene, and its abnormal expression contributes to tumor growth. Here, we identified IGF2 as a target of miR-615-5p using a luciferase reporter assay. IGF2 upregulation in PDAC tissues was not correlated with a loss of imprinting but was inversely correlated with miR-615-5p downregulation. In addition, miR-615-5p suppressed pancreatic cancer cell proliferation, migration and invasion by directly targeting IGF2, and this effect could be reversed by co-transfection with IGF2. Furthermore, the stable overexpression of miR-615-5p inhibited tumor growth in vivo and was correlated with IGF2 expression. Using RNA sequencing, we further identified miR-615-5p as potentially targeting other genes, such as the proto-oncogene JUNB, and interfering with the insulin signaling pathway. Taken together, our results demonstrate that miR-615-5p was abnormally downregulated in PDAC cells due to promoter hypermethylation, which limited its inhibition of IGF2 and other target genes, thereby contributing to tumor growth, invasion and migration. These data demonstrate a novel and important role of miR-615-5p as a tumor suppressor in PDAC.

Antinociceptive activity of CP-101,606, an NMDA receptor NR2B subunit antagonist.

1. The analgesic activity of CP-101,606, an NR2B subunit-selective N-methyl-D-aspartate (NMDA) receptor antagonist, was examined in carrageenan-induced hyperalgesia, capsaicin- and 4beta-phorbol-12-myristate-13-acetate (PMA)-induced nociceptive tests in the rat. 2. CP-101,606 30 mg kg(-1), s.c., at 0.5 and 2.5 h after carrageenan challenge suppressed mechanical hyperalgesia without any apparant alternations in motor coordination or behaviour in the rat. 3. CP-101,606 also inhibited capsaicin- and PMA-induced nociceptive responses (licking behaviour) with ED50 values of 7.5 and 5.7 mg kg(-1), s.c., respectively. 4. These results suggest that inhibition of the NR2B subunit of the NMDA receptor is effective in vivo at modulating nociception and hyperalgesia responses without causing the behavioural side effects often observed with currently available NMDA receptor antagonists.

Good prognosis of patients with acute promyelocytic leukemia who achieved second complete remission (CR) with a new retinoid, Am80, after relapse from CR induced by all-trans-retinoic acid.

A new synthetic retinoid, Am80, is effective in treating acute promyelocytic leukemia relapsed from all-trans-retinoic acid-induced complete remission (CR). We report here the long-term clinical outcomes of patients who achieved second CR with Am80. Of 24 evaluable patients, 14 achieved a second CR by Am80 therapy. Of those patients, 4 relapsed within 6 months, despite subsequent consolidation chemotherapy. Six patients underwent sibling or unrelated HLA-matched allogeneic bone marrow transplantation (BMT), and 4 are alive without relase for more than 49 months after achieving second CR. Four of 8 patients who did not receive BMT are alive without relapse for more than 49 months. Promyelocytic leukemia-retinoic acid receptor alpha (PML-RAR alpha) fusion transcript was undetectable by reverse transcriptase-polymerase chain reaction in all living patients. Therefore, if patients achieve second CR with Am80 and HLA-matched donors are available, BMT is the treatment of choice. However, it is noteworthy that CR was maintained for more than 49 months in half of the patients who did not receive BMT.

Efficacy of a selective histamine H2 receptor agonist, dimaprit, in experimental models of endotoxin shock and hepatitis in mice.

Dimaprit, a selective histamine H2 receptor agonist, was examined in experimental models of endotoxin shock and hepatitis in mice. Injection of lipopolysaccharide (8 mg/kg i.v.) into Balb/c mice resulted in an elevation of plasma tumor necrosis factor-alpha (TNF-alpha), reaching the maximal level at 1 h post-lipopolysaccharide (1147 U/ml). Oral administration of dimaprit 200 mg/kg, 1 h prior to lipopolysaccharide challenge, inhibited the increase in plasma TNF-alpha by 71% and also the survival rate was increased to 62.5% from 8.3% in the disease control. In a mouse hepatitis model, simultaneous injection of galactosamine (700 mg/kg i.v.) and lipopolysaccharide (3 micrograms/kg i.v.) into Balb/c mice caused an increase in plasma TNF-alpha, peaking at 1 h, followed by an elevation of L-alanine aminotransferase (E.C.2.6.1.2) activity at 4 h onward. Oral administration of dimaprit 200 mg/kg, 1 h prior to galactosamine and lipopolysaccharide, reduced the increase in plasma TNF-alpha by 99% and L-alanine aminotransferase by 82%. In vitro, dimaprit dose dependently inhibited the production of TNF-alpha in mouse peritoneal macrophages and human peripheral blood monocytes stimulated with lipopolysaccharide with IC50 values of 1 microM. The decrease in TNF-alpha production by dimaprit was reversed by cimetidine, a histamine H2 receptor antagonist. Dimaprit dose dependently suppressed TNF-alpha mRNA in human peripheral blood monocytes. These results suggest that activation of the histamine H2 receptor downregulates the production of TNF-alpha, and that histamine may be an important regulator in pathological conditions in which TNF-alpha plays an important role.

Granulocyte colony-stimulating factor receptor at various differentiation stages of normal and leukemic hematopoietic cells.

Granulocyte colony-stimulating factor (G-CSF) is the most important cytokine in granulopoiesis, and induces the proliferation and differentiation of normal bone marrow granulocytic precursors. The physiologic effect of G-CSF is mediated through binding to specific cell surface receptors for G-CSF. Using a newly-devised quantitative flow-cytometric assay, we analyzed the expression of G-CSF receptors on normal and leukemic hematopoietic cells. In normal donors, G-CSF receptors are widely expressed from CD34-positive immature bone marrow cells to mature peripheral granulocytes. The highest expression of G-CSF receptors is observed in peripheral granulocytes. In the bone marrow, the level of G-CSF receptors expression increases in the following order; CD34+ CD33- cells < CD34+ CD33+ cells < CD34- CD33+ cells, indicating that G-CSF receptors are expressed on myeloid cells from a very early stage of differentiation and that the level of expression increases with the progress of cell maturation. G-CSF receptors are also detected on blast cells of patients with acute myeloid leukemia (AML) and acute lymphoid leukemia (ALL). The number of cell surface receptors varies from patient to patient, and no clear correlation is observed between the expression of receptors and the leukemia subtype or the cell surface markers. In this respect, the clinical use of G-CSF should be carefully controlled in ALL as well as AML patients.

All-trans retinoic acid (ATRA) differentiates acute promyelocytic leukemia cells independently of P-glycoprotein (P-gp) related multidrug resistance.

Here the relationship between all-trans retinoic acid (ATRA)-resistance and P-glycoprotein (P-gp)-associated multidrug resistance (MDR) is discussed in acute promyelocytic leukemia (APL). First, the remission rates of ATRA therapy are similar in relapsed/refractory APL to the preceding chemotherapy given and in newly diagnosed APL. Second, MDR1 cDNA-transduced NB4 (NB4/MDR) cells accumulate less Rhodamine-123 (Rh123) than NB4 cells, but there is no difference in the intracellular ATRA concentration between them. PSC833 or MS209. MDR modifiers, increases the intracellular accumulation of Rh123 in NB4/MDR and APL cells expressing P-gp, but not of ATRA. Third, the expression of CD11b, the NBT reduction activity, the proportion of apoptotic cells and the morphology are not different between NB4/MDR and NB4 cells, and between APL cells expressing P-gp and not. APL cells express little P-gp, and mainly express CD33 but no CD34. Despite previous reports that ATRA-resistant APL cells express more P-gp than ATRA-sensitive ones, P-gp and ATRA-resistance seems to exist independently.

Stressful delivery influences circulating thrombopoietin (TPO) levels in newborns: possible role for cortisol in TPO-mpl binding.

The regulation mechanism of circulating thrombopoietin (TPO) level in human newborns remains unknown. In the present study, we examined whether the TPO concentrations in cord blood were influenced by the difference in the delivery method and the presence or absence of maternal/fetal complications. Cortisol levels were simultaneously measured to assess the adrenal response of fetuses. Both the TPO level and the cortisol level were substantially greater in the neonates delivered vaginally with and without the complications than in those delivered by cesarean section without the complications. The binding assay showed that the incubation of mpl(+)/BaF3 cells with cortisol gave rise to a significant decrease in the binding sites of TPO. These results suggest that the stress to the fetuses near the time of delivery affects the cord blood TPO levels, which may be mediated in part by the action of cortisol on the TPO-mpl binding system.

Dacron fabric-enveloped hydroxyapatite prosthesis for sternal tumor defect: an autopsy report.

A 38-year-old housewife with solitary plasmacytoma of the manubrium who underwent a subtotal sternectomy treated by resection of the lesion is reported. This was followed by replacement with a Dacron fabric-enveloped hydroxyapatite prosthesis. The Dacron fabric was sutured to the surrounding tissues, and then the clavicle was passed through the cylindrical-shaped Dacron fabric to form a sternoclavicular joint capsule. The patient returned to her daily life 3 months after the operation. She had no trouble in her daily living, without any dislocation of the sternoclavicular joints or any displacement of the artificial sternum. The autopsy examination about 1 year after the operation showed that the Dacron fabric enveloping the artificial sternum became stronger with time. The sternoclavicular joint also was stably fixed, and the Dacron fabric fulfilled its function as an artificial articular capsule and biologic fixation of the surrounding supporting tissues.

Effects of lumbar sympathectomy on thromboangiitis obliterans.

The clinical response to lumbar sympathectomy has been reported. The incidence of improvement was as follows: Coldness 52 percent, ulcer 58 percent, rest pain 64 percent, and claudication 31 percent, respectively. The blood flow in the anterior tibial muscles did not increase within 5 weeks postoperatively. There were correlations between the effects and the clinical stages, the interval from the onset to the operations, the abuse of tobacco, and the degree of reactive hyperemia, but not relation was observed between as to the site of obstruction. In the experiments, the influence of acetylcholine on blood flow increased after the operations and the duration of vasoconstriction following administration of noradrenalin became shorter. On the basis of the clinical and experimental facts, postoperative improvement seems to be due to increased blood flow to the peripheral skin and to relief of vasospasm.