A novel carbazole topoisomerase II poison,ER-37328: potent tumoricidal activity against human solid tumors in vitro and in vivo

We have discovered a novel topoisomerase II (topo II) poison, ER-37328 (12,13-dihydro-5-[2-(dimethylamino)ethyl]-4H-benzo[c]py-rimido[5,6,1- jk ]carbazole-4,6,10(5H, 11H)-trione hydrochloride), which shows potent tumor regression activity against Colon 38 cancer inoculated s.c. Here, we describe studies on the cell-killing activity against a panel of human cancer cell lines and the antitumor activity of ER-37328 against human tumor xenografts. In a cell-killing assay involving 1-h drug treatment, ER-37328 showed more potent cell-killing activity (50% lethal concentrations (LC₅₀s) ranging from 2.9 to 20 μM ) than etoposide (LC₅₀s>60 μM ) against a panel of human cancer cell lines. ER-37328 induced double-stranded DNA cleavage, an indicator of topo II-DNA cleavable complex formation, within 1 h in MX-1 cells, and the extent of cleavage showed a bell-shaped relationship to drug concentration, with the maximum at 2.5 μM . After removal of the drug (2.5 μM ) at 1 h, incubation was continued in drug-free medium, and the amount of cleaved DNA decreased. However, at 10 μM , which is close to the LC₅₀ against MX-1 cells, DNA cleavage was not detected immediately after 1-h treatment, but appeared and increased after drug removal. This result may explain the potent cell-killing activity of ER37328 in the 1-h treatment. In vivo , ER-37328 showed potent tumor regression activity against MX-1 and NS-3 tumors. Moreover, ER-37328 had a different antitumor spectrum from irinotecan or cisplatin against human tumor xenografts. In conclusion, ER-37328 is a promising topo II poison with strong cell killing activity in vitro and tumor regression activity in vivo , and is a candidate for the clinical treatment of malignant solid tumors. (Cancer Sci 2003; 94: 119–124)     

A case of polyarteritis nodosa limited to lower legs with a high titer of MPO-ANCA under precedence of idiopathic pulmonary fibrosis

A 58-year-old man with a 15-year history of idiopathic pulmonary fibrosis was hospitalized for rapid progression of muscle weakness to bilateral foot drop. Although laboratory data revealed high titers of myeloperoxidase anti-neutrophil cytoplasmic antibody (489 EU), the patient was diagnosed as polyarteritis nodosa limited to the lower portions of the legs. Despite of the treatment with large doses of corticosteroids and cyclosporin A, his symptoms barely improved during the following two months.     

Perinatal management and problems of preterm twins less than 32 weeks of gestation in Japan

Between 1983 and 1998 there were 23433 births at Kitasato University Hospital, including 359 births. A retrospective analysis was performed on 320 twin pairs analyzing survivability indexes with respect to fetal age, chorionicity and birth weight discordance. Furthermore, the paper illustrates an analysis of causes of neonatal deaths as well as the rate of various complications of twins delivered before 32 weeks gestation such as twin-twin transfusion syndrome and periventricular leukomalacia.     

Ex vivo delivery of suicide genes into melanoma cells using epidermal growth factor receptor-specific Fab immunogene.

The Fab fragment of monoclonal antibody B4G7 against human epidermal growth factor (EGF) receptor was conjugated with cationic poly-L-lysine and the resulting conjugate was further complexed with reporter genes or therapeutic genes. This Fab/DNA complex was designated as "Fab immunogene." The Fab immunogene transfer in vitro was mediated through the EGF receptors in two melanoma cell lines. The frequency of cells expressing beta-galactosidase (beta-Gal) reporter gene was approximately 1%. The induction of suicide effects after Fab immunogene transfer of herpes simplex virus thymidine kinase (TK) or Escherichia coli cytosine deaminase (CD) gene was quite remarkable, and the growth of melanoma cells was inhibited for over 7 days in the presence of ganciclovir (GCV) or 5-fluorocytosine (5-FC). Similarly, when melanoma cells treated in vitro with the Fab immunogene carrying TK or CD were transplanted into the back of nude mouse, subsequent systemic administration of GCV or 5-FC effectively suppressed the growth of tumors, indicating the occurrence of in vivo suicide effects.     

Behavioral abnormalities and apoptotic changes in neurons in mice brain following a single administration of allylnitrile

A single dose of allylnitrile in mice might induce persistent behavioral abnormalities, of which the mechanism is not yet known. The present study was undertaken to explore the relationship between behavioral abnormalities and pathological changes in the brain of mice following exposure to allylnitrile. Exposure to allylnitrile (63, 84, and 112 mg/kg, p.o.) resulted in dose-dependent changes in behavioral abnormalities, including increased locomotor activity, circling, retropulsion, head twitching, and alteration in reflexive behavior, which appeared at day 2 postdosing and were persistent throughout the experimental period (60 days) at the higher dose levels. Allylnitrile produced neuronal retraction including hyperchromasia of the nuclei in the raphe nuclei, cerebral cortex, hypothalamus, hippocampal CA1 and dentate gyrus later than 30 days. No gliosis was observed in these regions. Not all but a significant number of neurons in the hippocampal CA1, medial habenula and raphe nuclei were immunoreactive to CPP32 (Caspase-3) even at day 2. These neurons were also positive to Hoechst 33258 staining, indicating allylnitrile caused apoptotic changes in specific neurons when neuronal behaviors became apparent. These apoptotic changes were persistent even in the area without neuronal contraction such as medial habenula. However, almost all neurons in these areas were also positive to terminal deoxynucleotidyl transferase mediated dUTP-biotin nick end labeling (TUNEL). It is conceivable that allylnitrile caused apoptotic changes in neurons but did not always lead them to cell death immediately. Moreover, even when neuronal contraction resulted in retention of behavioral abnormalities, onset of these abnormalities seems to be associated with the impairment in the habenulo-raphe relay due to activation of apoptotic cascade in neurons. Received: 2 June 1998 / Accepted: 14 December 1998     

Ex vivo Delivery of Suicide Genes into Melanoma Cells Using Epidermal Growth Factor Receptor-specific Fab Immunogene

The Fab fragment of monoclonal antibody B4G7 against human epidermal growth factor (EGF) receptor was conjugated with cationic poly- l -lysine and the resulting conjugate was further complexed with reporter genes or therapeutic genes. This Fab/DNA complex was designated as "Fab immunogene". The Fab immunogene transfer in vitro was mediated through the EGF receptors in two melanoma cell lines. The frequency of cells expressing β-galactosidase ( β-Gal ) reporter gene was approximately 1%. The induction of suicide effects after Fab immunogene transfer of herpes simplex virus thymidine kinase ( TK ) or Escherichia coli cytosine deaminase ( CD ) gene was quite remarkable, and the growth of melanoma cells was inhibited for over 7 days in the presence of ganciclovir (GCV) or 5-fluorocytosine (5-FC). Similarly, when melanoma cells treated in vitro with the Fab immunogene carrying TK or CD were transplanted into the back of nude mouse, subsequent systemic administration of GCV or 5-FC effectively suppressed the growth of tumors, indicating the occurrence of in vivo suicide effects.     

Ocular hypotensive effects of monoamine oxidase-A inhibitors in rabbit

The effects of monoamine oxidase-A (MAO-A) inhibitors with epinephrine on intraocular pressure in the pigmented rabbit were studied. MAO-A inhibitors were used topically with or without various concentrations of epinephrine. For the measurement of intraocular pressure, applanation pneumatonography was used and tissue MAO activities were determined by radiometric assay. After topical administration with clorgyline, MAO-A activities in the bulbar conjunctiva and the iris-ciliary body were remarkably inhibited, whereas MAO-B inhibition was minimal. Maximal reduction of intraocular pressure with 0.05% epinephrine was 3.2 mmHg. Single administration of clorgyline, amiflamine, moclobemide or CGP 11305-A caused decreases in the intraocular pressure of 2.0, 2.5, 1.8 and 2.4 mmHg, respectively. In the coadministration experiments with epinephrine, the ocular hypotensive effects of epinephrine were potentiated with clorgyline, amiflamine, moclobemide and CGP 11305-A (6.6, 4.8, 5.6 and 5.8 mmHg). On the contrary, they were not influenced by the MAO-B inhibitor deprenyl. These results indicated that MAO-A inhibitors potentiated the ocular hypotensive effects of epinephrine, and that the coadministration of a reversible MAO-A inhibitor with epinephrine might be useful for patients with glaucoma.     

Preliminary experience of wireless teleradiology system using Personal Handyphone System]

We investigated the potential of the wireless teleradiology system, using a Personal Handyphone System(PHS) and hand-held personal computer. To provide and interpret CT images, an internet web system was used. It took 5.5 seconds to transmit a single CT image of 28 KB. Therefore, about 2 minutes was required to brawse a series of brain examinations(20 CT images). Although transmission speed needs to be increased, our system makes it possible to perform imaging diagnosis anywhere and is especially useful in emergency situations.     

Loss of astrocyte polarization in the tg-ArcSwe mouse model of Alzheimer's disease

Aquaporin-4 (AQP4) is the predominant water channel in brain and is selectively expressed in astrocytes. Astrocytic endfoot membranes exhibit tenfold higher densities of AQP4 than non-endfoot membranes, making AQP4 an excellent marker of astrocyte polarization. Loss of astrocyte polarization is known to compromise astrocytic function and to be associated with impaired water and K+ homeostasis. Here we investigate by a combination of light and electron microscopic immunocytochemistry whether amyloid deposition is associated with a loss of astrocyte polarization, using AQP4 as a marker. We used the tg-ArcSwe mouse model of Alzheimer's disease, as this model displays perivascular plaques as well as plaques confined to the neuropil. 3D reconstructions were done to establish the spatial relation between plaques and astrocytic endfeet, the latter known to contain the perivascular pool of AQP4. Changes in AQP4 expression emerge just after the appearance of the first plaques. Typically, there is a loss of AQP4 from endfoot membranes at sites of perivascular amyloid deposits, combined with an upregulation of AQP4 in the neuropil surrounding plaques. By electron microscopy it could be verified that the upregulation reflects an increased concentration of AQP4 in those delicate astrocytic processes that abound in synaptic regions. Thus, astrocytes exhibit a redistribution of AQP4 from endfoot membranes to non-endfoot membrane domains. The present data suggest that the development of amyloid deposits is associated with a loss of astrocyte polarization. The possible perturbation of water and K+ homeostasis could contribute to cognitive decline and seizure propensity in patients with Alzheimer's disease.     

Evaluation of cortical processing of language by use of positron emission tomography in hearing loss children with congenital cytomegalovirus infection

Objective

To predict cochlear implant efficacy and investigate the cortical processing of the visual component of language in profoundly deafened patients with asymptomatic congenital cytomegalovirus (CMV) infection.

Methods and cases

The cortical activity of two children with CMV-related hearing loss was evaluated with fluorodeoxyglucose-positron emission tomography (FDG-PET) with a visual language task before cochlear implantation. Total development and auditory perception ability were assessed one year after implantation.

Results

The two children with CMV-related hearing loss showed activation in the auditory association area where no activation was found in the controls, and exhibited nearly identical cortical activation patterns to those seen in patients with profound congenital hearing loss. In contrast, differences in total development in verbal ability and discrimination of sentences between the two cases were revealed one year after implantation.

Conclusion

These results might indicate that the differences of cortical activities according to hearing abilities could have been influenced by CMV infection that involves higher function of the brain directly and/or affects the cochlea peripherally. Additionally, if CMV infection might have affected only the cochlea, these cortical activation patterns were influenced secondary by the time course of hearing loss characterized by CMV infection, which had varied manifestations.Accurate diagnosis and cochlear implantation at the appropriate time are important for successful speech development, and each patient needs a personalized habilitation program based on their etiology and brain function.