Brominated 7-hydroxycoumarin-4-ylmethyls: photolabile protecting groups with biologically useful cross-sections for two photon photolysis

Photochemical release (uncaging) of bioactive messengers with three-dimensional spatial resolution in light-scattering media would be greatly facilitated if the photolysis could be powered by pairs of IR photons rather than the customary single UV photons. The quadratic dependence on light intensity would confine the photolysis to the focus point of the laser, and the longer wavelengths would be much less affected by scattering. However, previous caged messengers have had very small cross sections for two-photon excitation in the IR region. We now show that brominated 7-hydroxycoumarin-4-ylmethyl esters and carbamates efficiently release carboxylates and amines on photolysis, with one- and two-photon cross sections up to one or two orders of magnitude better than previously available. These advantages are demonstrated on neurons in brain slices from rat cortex and hippocampus excited by glutamate uncaged from N-(6-bromo-7-hydroxycoumarin-4-ylmethoxycarbonyl)-L-glutamate (Bhc-glu). Conventional UV photolysis of Bhc-glu requires less than one-fifth the intensities needed by one of the best previous caged glutamates, gamma-(alpha-carboxy-2-nitrobenzyl)-L-glutamate (CNB-glu). Two-photon photolysis with raster-scanned femtosecond IR pulses gives the first three-dimensionally resolved maps of the glutamate sensitivity of neurons in intact slices. Bhc-glu and analogs should allow more efficient and three-dimensionally localized uncaging and photocleavage, not only in cell biology and neurobiology but also in many technological applications.

Magnitude and time course of microvascular obstruction and tissue injury after acute myocardial infarction

BACKGROUND

Microvascular obstruction within an area of myocardial infarction indicates worse functional recovery and a higher risk of postinfarction complications. After prolonged coronary occlusion, contrast-enhanced MRI identifies myocardial infarction as a hyperenhanced region containing a hypoenhanced core. Because the time course of microvascular obstruction after infarction/reperfusion is unknown, we examined whether microvascular obstruction reaches its full extent shortly after reperfusion or shows significant progression over the following 2 days.

METHODS AND RESULTS

Seven dogs underwent 90-minute balloon occlusion of the left anterior descending coronary artery (LAD) followed by reflow. Gadolinium-DTPA-enhanced MRI performed at 2, 6, and 48 hours after reperfusion was compared with radioactive microsphere blood flow (MBF) measurements and myocardial staining to define microvascular obstruction (thioflavin S) and infarct size (triphenyltetrazolium chloride, TTC). The MRI hypoenhanced region increased 3-fold during 48 hours after reperfusion (3.2+/-1.8%, 6.7+/-4.4%, and 9.9+/-3.2% of left ventricular mass at 2, 6, and 48 hours, respectively, P<0.03) and correlated well with microvascular obstruction (MBF <50% of remote region, r=0.99 and thioflavin S, r=0.93). MRI hyperenhancement also increased (21.7+/-4.0%, 24.3+/-4.6%, and 28.8+/-5.1% at 2, 6, and 48 hours, P<0.006) and correlated well with infarct size by TTC (r=0.92). The microvascular obstruction/infarct size ratio increased from 13.0+/-4.8% to 22.6+/-8.9% and to 30.4+/-4.2% over 48 hours (P=0.024).

CONCLUSION

The extent of microvascular obstruction and the infarct size increase significantly over the first 48 hours after myocardial infarction. These results are consistent with progressive microvascular and myocardial injury well beyond coronary occlusion and reflow.

Photo-mediated gene activation using caged RNA/DNA in zebrafish embryos

We report a new and simple technique for photo-mediated temporal and spatial control of gene activation in zebrafish embryos as an alternative to the gene 'knockdown' approach using antisense, morpholino-modified oligonucleotides (morpholinos). The synthetic compound 6-bromo-4-diazomethyl-7-hydroxycoumarin (Bhc-diazo) forms a covalent bond with the phosphate moiety of the sugar-phosphate backbone of RNA, a process known as caging. The 6-bromo-7-hydroxycoumarin-4-ylmethyl (Bhc) group binds to approximately 30 sites on the phosphate moieties per 1 kb of RNA sequence. Bhc-caged mRNA undergoes photolysis (uncaging) when exposed to long-wave ultraviolet light (350 to 365 nm). We show that Bhc-caged green fluorescent protein (Gfp) mRNA has severely reduced translational activity in vitro, whereas illumination of Bhc-caged mRNA with ultraviolet light leads to partial recovery of translational activity. Bhc-caged mRNA is highly stable in zebrafish embryos. In embryos injected with Bhc-caged Gfp mRNA at the one-cell stage, GFP protein expression and fluorescence is specifically induced by ultraviolet light. We also show that, consistent with results obtained using other methods, uncaging eng2a (which encodes the transcription factor Engrailed2a) in the head region during early development causes a severe reduction in the size of the eye and enhanced development of the midbrain and the midbrain-hindbrain boundary at the expense of the forebrain.

Immunocytochemical localization of candidates for vesicular glutamate transporters in the rat cerebral cortex

Brain-specific Na(+)-dependent inorganic phosphate cotransporter (BNPI) was recently reported to serve as a vesicular glutamate transporter (VGluT), and was renamed VGluT1 (Bellocchio et al. [ 2000] Science 289:957-960; Takamori et al. [2000] Nature 407:189-194). Ahead of these reports, cDNA encoding another brain-specific inorganic phosphate transporter, which showed 82% amino acid identity to VGluT1, was cloned and designated differentiation-associated Na(+)-dependent inorganic phosphate cotransporter (DNPI; Aihara et al. [2000] J Neurochem 74:2622-2625). In the present study, we produced a specific antibody against a C-terminal portion of DNPI, and studied the immunohistochemical localization of DNPI in the rat cerebral cortex in comparison with that of VGluT1. DNPI immunoreactivity was enriched in neuropil of layers I and IV and to a lesser extent in the upper portion of layer VI of the cerebral neocortex, whereas VGluT1 immunoreactivity was distributed more evenly in neuropil of the neocortex. Electron microscopic observation revealed that both DNPI and VGluT1 immunoreactivities were mainly located on synaptic vesicles in nerve terminals which made asymmetrical contacts in the neocortex. Furthermore, neither DNPI nor VGluT1 immunoreactivity in the neocortex was colocalized with gamma aminobutyric acid (GABA)ergic axon terminal markers, immunoreactivity for glutamic acid decarboxylase or vesicular GABA transporter. Neuronal depletion in the ventrobasal thalamic nuclei produced by the kainic acid injection resulted in a clear reduction of DNPI immunoreactivity in layers I, IV, and VI of the somatosensory cortex. These results indicate that DNPI is located on the membrane of synaptic vesicles in thalamocortical axon terminals, and that it may be a candidate for VGluT of thalamocortical glutamatergic neurons.

Ultrastructural features of the adult hermaphrodite gonad of Caenorhabditis elegans: relations between the germ line and soma

Genetic and embryological experiments have established the Caenorhabditis elegans adult hermaphrodite gonad as a paradigm for studying the control of germline development and the role of soma-germline interactions. We describe ultrastructural features relating to essential germline events and the soma-germline interactions upon which they depend, as revealed by electron and fluorescence microscopy. Gap junctions were observed between oocytes and proximal gonadal sheath cells that contract to ovulate the oocyte. These gap junctions must be evanescent since individual oocytes lose contact with sheath cells when they are ovulated. In addition, proximal sheath cells are coupled to each other by gap junctions. Within proximal sheath cells, actin/myosin bundles are anchored to the plasma membrane at plaque-like structures we have termed hemi-adherens junctions, which in turn are closely associated with the gonadal basal lamina. Gap junctions and hemi-adherens junctions are likely to function in the coordinated series of contractions required to ovulate the mature oocyte. Proximal sheath cells are fenestrated with multiple small pores forming conduits from the gonadal basal lamina to the surface of the oocyte, passing through the sheath cell. In most instances where pores occur, extracellular yolk particles penetrate the gonadal basal lamina to directly touch the underlying oocytes. Membrane-bounded yolk granules were generally not found in the sheath cytoplasm by either electron microscopy or fluorescence microscopy. Electron microscopic immunocytochemistry was used to confirm and characterize the appearance of yolk protein in cytoplasmic organelles within the oocyte and in free particles in the pseudocoelom. The primary route of yolk transport apparently proceeds from the intestine into the pseudocoelom, then through sheath pores to the surface of the oocyte, where endocytosis occurs. Scanning electron microscopy was used to directly visualize the distal tip cell which extends tentacle-like processes that directly contact distal germ cells. These distal tip cell processes are likely to play a critical role in promoting germline mitosis. Scanning electron microscopy also revealed thin filopodia extending from the distal sheath cells. Distal sheath filopodia were also visualized using a green fluorescent protein reporter gene fusion and confocal microscopy. Distal sheath filopodia may function to stretch the sheath over the distal arm.

CYP2C19 genotype status and effect of omeprazole on intragastric pH in humans

OBJECTIVE

Omeprazole is metabolized by genetically determined S-mephenytoin 4'-hydroxylase (CYP2C19) in the liver. This study aimed to determine whether the effect of omeprazole on intragastric pH depends on CYP2C19 genotype status.

METHODS

CYP2C19 genotype status for 2 mutations associated with the poor metabolizer phenotype was determined by a polymerase chain reaction-restriction fragment length polymorphism method in 16 healthy volunteers. Helicobacterpylori status was determined by serology and the [13C]urea breath test. After a single oral administration of 20 mg omeprazole or a placebo, intragastric pH values were recorded for 24 hours. Plasma levels of omeprazole and its 2 metabolites and gastrin were measured before and 1, 2, 3, 5, 7, 10, and 24 hours after administration.

RESULTS

Fifteen of the 16 subjects were H pylori negative. Five of the 15 subjects were homozygous extensive metabolizers, 4 were heterozygous extensive metabolizers, and 6 were poor metabolizers. After omeprazole administration, significant differences in mean intragastric pH values and plasma levels of gastrin, omeprazole and its metabolites were observed among the 3 groups, whereas no significant differences in these parameters were observed with the placebo administration.

CONCLUSIONS

The effect of omeprazole on intragastric pH significantly depends on CYP2C19 genotype status. The genotyping test of CYP2C19 may be useful for an optimal prescription of omeprazole.

Effect of genetic differences in omeprazole metabolism on cure rates for Helicobacter pylori infection and peptic ulcer

BACKGROUND

Omeprazole is metabolized by S-mephenytoin 4'-hydroxylase (CYP2C19) in the liver. In persons with a poor-metabolizer genotype for CYP2C19, the therapeutic efficacy of omeprazole may be increased.

OBJECTIVE

To investigate whether CYP2C19 genotype status is associated with cure rates for Helicobacterpylori infection and peptic ulcer achieved by using dual therapy with omeprazole and amoxicillin.

DESIGN

Prospective cohort study.

SETTING

University hospital and health service center in Hamamatsu, Japan.

PATIENTS

62 patients with peptic ulcer and H. pylori infection.

INTERVENTION

Omeprazole and amoxicillin.

MEASUREMENTS

CYP2C19 genotype status and cure rates for H. pylori infection and peptic ulcer.

RESULTS

Cure rates for H. pylori infection were 28.6% (95% CI, 13.1% to 48.7%), 60% (CI, 38.6% to 83.0%), and 100% (CI, 66.4% to 100%) in the rapid-, intermediate-, and poor-metabolizer groups, respectively. Healing rates for both duodenal and gastric ulcer in the three groups were roughly parallel with cure rates for H. pylori infection.

CONCLUSION

The results of the genotyping test for CYP2C19 seem to predict cure of H. pylori infection and peptic ulcer in patients who receive dual therapy with omeprazole and amoxicillin.

The role of macrophages in diabetic glomerulosclerosis

To elucidate the role of macrophages in diabetic glomerulosclerosis (DGS), an immunohistologic study was performed using monoclonal antibodies to common leukocyte antigen (DAKO-LC), T cells (T3), B cells (CD22), and macrophages (MAC 387, Leu-M5, and EBM-11). Kidney biopsy specimens were obtained from 28 patients with non-insulin-dependent diabetes mellitus. Cells were identified by a three-layer immunoperoxidase technique applied to cold ethanol-fixed, paraffin-embedded sections and quantitated as the number of cells per glomerular cross-sections and number of cells per square millimeter of glomerulus. The severity of the diffuse lesions in each glomerulus was graded semiquantitatively. The average grades for all the glomeruli were calculated and registered as an index of DGS for a biopsy specimen. There was no relationship between the index of DGS and the number of T or B cells. However, the number of macrophages and common leukocyte-positive cells increased significantly in the moderate stage of glomerulosclerosis compared with the mild or advanced stage. The results suggest that macrophages may transiently infiltrate during the moderate stage of diffuse DGS, contributing to irreversible structural damage.

Tonsillectomy and steroid pulse therapy significantly impact on clinical remission in patients with IgA nephropathy

We conducted a retrospective investigation of renal outcome in 329 patients with immunoglobulin A (IgA) nephropathy with an observation period longer than 36 months (82.3 +/- 38.2 months) in our renal unit between 1977 and 1995. Clinical remission, renal progression, and the impact of covariates were estimated by Kaplan-Meier analysis and a Cox regression model. In 157 of 329 patients (48%), disappearance of urinary abnormalities (clinical remission) was obtained. None of these 157 patients showed progressive deterioration, defined as a 50% increase in serum creatinine (Scr) level from baseline, during the observation period. Conversely, in patients without clinical remission, the Kaplan-Meier estimate of probability of progressive deterioration was 21% +/- 5% at 10 years. In the multivariate Cox regression model with 13 independent covariates, initial Scr level, histological score, tonsillectomy, and high-dose methylprednisolone therapy had a significant impact on clinical remission, whereas proteinuria, age, sex, levels of hematuria, blood pressure, conventional steroid therapy, angiotensin-converting enzyme inhibitor therapy, and cyclophosphamide therapy had no significant effect. These findings indicate that interventions aimed at achieving clinical remission have provided encouraging results applicable to managing patients with IgA nephropathy.

Effect of genotypic differences in CYP2C19 on cure rates for Helicobacter pylori infection by triple therapy with a proton pump inhibitor, amoxicillin, and clarithromycin

BACKGROUND

Proton pump inhibitors such as omeprazole and lansoprazole are mainly metabolized by CYP2C19 in the liver. The therapeutic effects of proton pump inhibitors are assumed to depend on CYP2C19 genotype status.

OBJECTIVE

We investigated whether CYP2C19 genotype status was related to eradication rates of H pylori by triple proton pump inhibitor-clarithromycin-amoxicillin (INN, amoxicilline) therapy and attempted to establish a strategy for treatment after failure to eradicate H pylori.

METHODS

A total of 261 patients infected with H pylori completed initial treatment with 20 mg of omeprazole or 30 mg of lansoprazole twice a day, 200 mg of clarithromycin three times a day, and 500 mg of amoxicillin three times a day for 1 week. CYP2C19 genotypes of patients were determined with polymerase chain reaction-restriction fragment length polymorphism analysis. Patients without eradication after initial treatment were retreated with 30 mg of lansoprazole four times daily and 500 mg of amoxicillin four times daily for 2 weeks.

RESULTS

Eradication rates for H pylori were 72.7% (95% confidence interval, 64.4%-81.8%), 92.1% (confidence interval, 86.4%-97.3%), and 97.8% (confidence interval, 88.5%-99.9%) in the homozygous extensive, heterozygous extensive, and poor metabolizer groups, respectively. Thirty-four of 35 patients without eradication had an extensive metabolizer genotype of CYP2C19. Nineteen of those patients were infected with clarithromycin-resistant strains of H pylori. However, there were no amoxicillin-resistant strains of H pylori. Re-treatment of H pylori infection with dual high-dose lansoprazole-amoxicillin therapy succeeded in 30 of 31 patients with extensive metabolizer genotype of CYP2C19.

CONCLUSION

The majority of patients without initial eradication of H pylori had an extensive metabolizer CYP2C19 genotype but were successfully re-treated with high doses of lansoprazole and an antibiotic to which H pylori was sensitive, such as amoxicillin, even when the patients were infected with clarithromycin-resistant strains of H pylori.

Limited hepatic resection effective for selected cirrhotic patients with primary liver cancer

We evaluated in retrospect the applicability of limited hepatic resection in cases of primary liver cancer in cirrhotic patients. According to the severity of impaired liver function, 37 patients underwent limited resection, and for 13, standard major hepatic resection was done. The mortality rate in case of limited resection was 10.8%, and the rate in case of massive excision was 15.4%. One, two- and five-year survival rates of limited operation were 79.9, 60.3, and 32.6%, respectively. After standard resection, the rates were 78.7, 67.5, and 22.5%, respectively. There were no significant differences in the mortality and survival rates between the two groups. These results indicate that, for the patient with a small liver cancer, and poor liver function, the limited procedure leads to a comparatively longer survival. This limited resection can be selectively used to treat cancer associated with cirrhosis and encapsulated tumors. For the preoperative evaluation, hepatic arteriograms aid in patient selection.

Synthesis and antitumor activity of 20(S)-camptothecin derivatives: carbamate-linked, water-soluble derivatives of 7-ethyl-10-hydroxycamptothecin

Novel 36 derivatives (6), bonding the phenolic hydroxyl group of 7-ethyl-10-hydroxycamptothecin (4) with diamines through a monocarbamate linkage, were synthesized and their antitumor activity was evaluated in vivo. The derivatives were soluble in water as their HCl salts with the E lactone ring intact and exhibited significant antitumor activity. One of the derivatives, 6-27 showed excellent activity against L1210 leukemia and other murine tumors. The structure of its hydrochloride trihydrate (CPT-11) was determined by spectroscopic and crystallographic methods.

Differential distribution of vesicular glutamate transporters in the rat cerebellar cortex

The chemical organization of excitatory axon terminals in the rat cerebellar cortex was examined by immunocytochemistry and in situ hybridization histochemistry of vesicular glutamate transporters 1 and 2 (VGluT1 and VGluT2). Chemical depletion of the inferior olivary complex neurons by 3-acetylpyridine treatment almost completely removed VGluT2 immunoreactivity from the molecular layer, leaving VGluT1 immunoreactivity apparently intact. On the other hand, neuronal deprivation of the cerebellar cortex by kainic acid injection induced a large loss of VGluT1 immunoreactivity in the molecular layer. In the cerebellar granular layer, both VGluT1 and VGluT2 immunoreactivities were found in mossy fiber terminals, and the two immunoreactivities were mostly colocalized in single-axon terminals. Signals for mRNA encoding VGluT2 were found in the inferior olivary complex, and those for VGluT1 and VGluT2 mRNAs were observed in most brainstem precerebellar nuclei sending mossy fibers, such as the pontine, pontine tegmental reticular, lateral reticular and external cuneate nuclei. These results indicate that climbing and parallel fibers selectively use VGluT2 and VGluT1, respectively, whereas mossy fibers apply both VGluT1 and VGluT2 together to accumulate glutamate into synaptic vesicles. Since climbing-fiber and parallel-fiber terminals are known to make depressing and facilitating synapses, respectively, VGluT1 and VGluT2 might have distinct properties associated with those synaptic characteristics. Thus, it would be the next interesting issue to determine whether mossy-fiber terminals co-expressing VGluT1 and VGluT2 show synaptic facilitation or depression.

Effects of CYP2C19 genotypic differences in the metabolism of omeprazole and rabeprazole on intragastric pH

BACKGROUND

Omeprazole is mainly metabolized in the liver by CYP2C19, a genetically determined enzyme, whereas rabeprazole is mainly reduced non-enzymatically and partially metabolized by CYP2C19. The therapeutic effects of rabeprazole are therefore assumed to be less affected by an individual's CYP2C19 status.

AIM

To investigate the acid inhibitory effects and plasma levels of omeprazole and rabeprazole with reference to different CYP2C19 genotypes.

METHODS

Fifteen healthy volunteers took a daily dose of 20 mg of omeprazole or rabeprazole for 8 days. On post-dose days 1 and 8, 24-h profiles of intragastric pH were recorded and plasma concentrations of omeprazole, rabeprazole and their metabolites were determined.

RESULTS

After single and repeated doses of omeprazole, the intragastric pH values and plasma concentrations of omeprazole and its metabolites were significantly dependent on the CYP2C19 genotype. Significant differences in the same kinetic and dynamic parameters were also observed after single doses of rabeprazole. Although the plasma levels of rabeprazole differed among the different CYP2C19 genotype groups after repeated doses, no significant differences in intragastric pH values were observed.

CONCLUSIONS

The acid inhibitory effects of omeprazole and rabeprazole are significantly dependent on the CYP2C19 genotype status, as well as on their intrinsic pharmacokinetic and pharmacodynamic characteristics and dosing schemes.

Potent acid inhibition by vonoprazan in comparison with esomeprazole, with reference to CYP2C19 genotype

BACKGROUND

Acid inhibitory effects of proton pump inhibitors (PPIs) are influenced by CYP2C19 genotype. In contrast, the potent acid inhibition of vonoprazan is not influenced by CYP2C19 genotype.

AIM

To compare the acid inhibitory effects of vonoprazan and esomeprazole in relation to CYP2C19 genotype.

METHODS

Twenty-eight healthy Japanese volunteers [7 CYP2C19 poor metabolisers (PMs), 11 intermediate metabolisers (IMs) and 10 rapid metabolisers (RMs)] received four different regimens in a randomised crossover manner: (i) vonoprazan 20 mg twice daily (b.d.), (ii) vonoprazan 20 mg daily, (iii) esomeprazole 20 mg b.d. and (iv) esomeprazole 20 mg daily. The timing of each dosing was 1 h before a meal. Twenty-four-hour intragastric pH monitoring was performed on day 7 on each regimen.

RESULTS

In the overall genotype group, pH ≥4 holding time ratios (pH 4 HTRs) with vonoprazan b.d., vonoprazan daily, esomeprazole b.d. and esomeprazole daily were 100%, 95%, 91%, and 68% respectively. pH 5 HTRs were 99%, 91%, 84% and 54% respectively. Vonoprazan b.d. potently suppressed acid for 24 h, and was significantly superior to other regimens irrespective of CYP2C19 genotype. Vonoprazan daily was equivalent to esomeprazole b.d. in IMs and PMs, but superior in RMs. CYP2C19 genotype-dependent differences were observed in esomeprazole daily but not in vonoprazan b.d. or daily.

CONCLUSION

Vonoprazan 20 mg b.d. inhibits acid irrespective of CYP2C19 genotype, more potently than esomeprazole 20 mg b.d., pH 4 and 5 holding time ratios reached 100% and 99%, respectively.

A 5-year experience of lipiodolization: selective regional chemotherapy for 200 patients with hepatocellular carcinoma

Between 1982 and 1987, selective regional cancer chemotherapy using Lipiodol plus an anticancer drug (lipiodolization) was prescribed for 200 patients with hepatocellular carcinoma. One hundred forty-nine patients were given lipiodolization alone, and the remaining 51 underwent hepatic resection following lipiodolization. The grades of deposits of the oily contrast medium in the neoplastic tissue seen on the plain X-ray correlated well with the antitumor effect. In the resected specimens of 17 patients treated with lipiodolization prior to surgery, concentrations of adriamycin in the malignant liver tissues were 13.2 +/- 18.2 micrograms per gm, whereas the adjacent liver parenchyma contained 1.4 +/- 2.0 micrograms per gm of adriamycin; the difference was statistically significant (p less than 0.05). In the 149 patients treated with lipiodolization, 1-, 2-, 3- and 4-year survival rates were 56.1, 28.9, 17.3 and 7.4%, respectively. Thus, lipiodolization was considerably more effective, compared to the results achieved by hepatic artery ligation and cannulation into the hepatic artery for patients in Stages I and II. In this sequential nonrandomized study, the survival rates for patients undergoing hepatic resection were superior to those for patients in Stage I and treated with lipiodolization. The significant difference appeared to depend on incomplete killing of tumor cells, which are most often present in the fibrous capsule, by lipiodolization. We conclude from these data that lipiodolization is an effective treatment for hepatocellular carcinoma when the tumor is not curatively resectable. When the clinical status is good, then surgery is warranted.

Pharmacogenomics-based tailored versus standard therapeutic regimen for eradication of H. pylori

Helicobacter pylori eradication rates by triple therapy with a proton pump inhibitor, amoxicillin, and clarithromycin at standard doses depend on bacterial susceptibility to clarithromycin and patient CYP2C19 genotypes. We examined the usefulness of a personalized therapy for H. pylori infection based on these factors as determined by genetic testing. First, optimal lansoprazole dosing schedules that would achieve sufficient acid inhibition to allow H. pylori eradication therapy in each of different CYP2C19 genotype groups were determined by a 24-h intragastric pH monitoring. Next, 300 H. pylori-positive patients were randomly assigned to the standard regimen group (lansoprazole 30 mg twice daily (b.i.d.)), clarithromycin 400 mg b.i.d., and amoxicillin 750 mg b.i.d. for 1 week) or the tailored regimen group based on CYP2C19 status and bacterial susceptibility to clarithromycin assessed by genetic testing. Patients with failure of eradication underwent the second-line regimen. The per-patient cost required for successful eradication was calculated for each of the groups. In the first-line therapy, the intention-to-treat eradication rate in the tailored regimen group was 96.0% (95% CI=91.5-98.2%, 144/150), significantly higher than that in the standard regimen group (70.0%: 95% CI=62.2-77.2%, 105/150) (P<0.001). Final costs per successful eradication in the tailored and standard regimen groups were $669 and $657, respectively. In conclusion, the pharmacogenomics-based tailored treatment for H. pylori infection allowed a higher eradication rate by the initial treatment without an increase of the final per-patient cost for successful eradication. However, the precise cost-effectiveness of this strategy remains to be determined.

Serine/Threonine Kinase MLK4 Determines Mesenchymal Identity in Glioma Stem Cells in an NF-κB-dependent Manner

Activation of nuclear factor κB (NF-κB) induces mesenchymal (MES) transdifferentiation and radioresistance in glioma stem cells (GSCs), but molecular mechanisms for NF-κB activation in GSCs are currently unknown. Here, we report that mixed lineage kinase 4 (MLK4) is overexpressed in MES but not proneural (PN) GSCs. Silencing MLK4 suppresses self-renewal, motility, tumorigenesis, and radioresistance of MES GSCs via a loss of the MES signature. MLK4 binds and phosphorylates the NF-κB regulator IKKα, leading to activation of NF-κB signaling in GSCs. MLK4 expression is inversely correlated with patient prognosis in MES, but not PN high-grade gliomas. Collectively, our results uncover MLK4 as an upstream regulator of NF-κB signaling and a potential molecular target for the MES subtype of glioblastomas.

Glycogen synthase kinase-3β is a pivotal mediator of cancer invasion and resistance to therapy

Tumor cell invasion and resistance to therapy are the most intractable biological characteristics of cancer and, therefore, the most challenging for current cancer research and treatment paradigms. Refractory cancers, including pancreatic cancer and glioblastoma, show an inextricable association between the highly invasive behavior of tumor cells and their resistance to chemotherapy, radiotherapy and targeted therapies. These aggressive properties of cancer share distinct cellular pathways that are connected to each other by several molecular hubs. There is increasing evidence to show that glycogen synthase kinase (GSK)‐3β is aberrantly activated in various cancer types and this has emerged as a potential therapeutic target. In many but not all cancer types, aberrant GSK3β sustains the survival, immortalization, proliferation and invasion of tumor cells, while also rendering them insensitive or resistant to chemotherapeutic agents and radiation. Here we review studies that describe associations between therapeutic stimuli/resistance and the induction of pro‐invasive phenotypes in various cancer types. Such cancers are largely responsive to treatment that targets GSK3β. This review focuses on the role of GSK3β as a molecular hub that connects pathways responsible for tumor invasion and resistance to therapy, thus highlighting its potential as a major cancer therapeutic target. We also discuss the putative involvement of GSK3β in determining tumor cell stemness that underpins both tumor invasion and therapy resistance, leading to intractable and refractory cancer with dismal patient outcomes.

Effects of Helicobacter pylori infection on gastric acid secretion and serum gastrin levels in Mongolian gerbils

BACKGROUND AND AIMS

Body gastritis caused by Helicobacter pylori infection appears to inhibit gastric acid secretion. The aim of this study was to determine the effects of H pylori infection on gastric acid secretion and clarify its mechanisms with reference to interleukin 1beta (IL-1beta).

METHODS

(1) Mongolian gerbils were inoculated orally with H pylori. Before, six, and 12 weeks after inoculation, serum gastrin levels, gastric acid output, and IL-1beta mRNA levels in the gastric mucosa were determined. Pathological changes were also determined according to the updated Sydney system. (2) Effects of recombinant human IL-1 receptor antagonist (rhIL-1ra) on gastric acid output and serum gastrin levels were also determined.

RESULTS

(1) Scores for activity and inflammation of gastritis and serum gastrin levels were significantly increased, and gastric acid output was significantly decreased six and 12 weeks after inoculation with H pylori. IL-1beta mRNA levels in the gastric mucosa were also elevated six and 12 weeks after inoculation with H pylori. (2) Acid output and serum gastrin levels in the infected groups returned to control levels after rhIL-1ra injection.

CONCLUSIONS

Gastric acid secretion is decreased and serum gastrin levels are increased in Mongolian gerbils infected with H pylori. This change in gastric acid secretion appears to be mediated by IL-1beta induced by H pylori infection.

Antitumor activity of a camptothecin derivative, CPT-11, against human tumor xenografts in nude mice

The antitumor effects of the camptothecin (CPT) derivative CPT-11, 7-ethyl-10-[4-(1-piperidino)-1-piperidino]-carbonyloxycamptothecin , were tested on human tumor xenografts in nude mice. CPT-11 showed antitumor activity higher than that of Adriamycin, 5-fluorouracil, or futraful, with little or no reduction of body weight being observed in the mice. The growth of colon adenocarcinoma Co-4 was significantly inhibited after a single i.v. injection of CPT-11 at 25, 50, or 100 mg/kg. The single i.v. injection was also significantly effective against mammary carcinoma MX-1 and gastric adenocarcinoma St-15. All of the mice bearing MX-1 tumors were cured by the administration of CPT-11 every 4 days for a total of three treatments at a total dose of 200 mg/kg given i.v. or of 400 mg/kg given p.o. Three i.v. or oral treatments were also effective against Co-4, St-15, gastric adenocarcinoma SC-6, and squamous-cell lung carcinoma QG-56. To achieve the same efficacy attained by i.v. injection, however, oral doses 2-4 times higher than the i.v. doses were required. When the total dose was fixed at 100 mg/kg, a triple i.v. injection was most effective, followed by a single i.v. injection and, finally daily p.o. administration for 10 days. Although SN-38 (7-ethyl-10-hydroxycamptothecin), a metabolite of CPT-11, showed much stronger cytotoxic activity in vitro than did CPT-11, its antitumor effects were similar, if not inferior, to those of CPT-11 in vivo at the same dose level. CPT-11 was converted into SN-38 by human tumors, but the sensitivity of these tumors to CPT-11 in vivo was independent of their ability to produce SN-38. These results suggest that CPT-11 may be clinically effective, depending on the schedule of administration, but that its effectiveness is not related to the ability of the tumor to produce SN-38.