P1-02-09: Epigenetics-Regulated microRNAs Related with Epithelial-Mesenchymal Transition of Breast Cancer Cells

Background: Epithelial-mesenchymal transition (EMT) is a program in which biological cells change morphologically and functionally from an epithelial phenotype to a mesenchymal phenotype. The EMT is involved in the process of cancer metastasis. On the other hand, accumulated evidence showed epigenetics and microRNA plays important roles in breast cancer. However, to date, biological networks between epigenetics and microRNAs regarding EMT remains largely unclear. Thus, the aim of this study is to identify epigenetics-regulated microRNAs related with EMT of breast cancer.

Materials / Methods and Results: MicroRNA expression profiles of 11 breast cancer cell lines (8 epithelial-phenotype (E-type) cells and 3 mesenchymal-phenotype (M-type) cells) were obtained by microarray method. Unsupervised clustering analysis showed that E- and M-type breast cancer cells had different microRNA expression profiles. On the other hand, we obtained a genomewide methylation status of these breast cancer cell lines by a MeDIP-seq method. An integrated in silico analysis identified microRNAs which microRNA and DNA methylation were inversely correlated. All of miR-200b/a/429 cluster members were listed in top5 differentially expressed miRs between E-and M-type cells, and also in top 5 epigenetics-regulated microRNAs. In the further study, we focused upon the miR-200b/a/429 cluster. A COBRA assay revealed that promoter regions of miR-200b/a/429 cluster in M-type breast cancer cells were more frequently methylated than that in E-type cells (65.1% vs 6.8%, p<0.0001, respectively). The methylation levels were inversely associated with miR-200b/a/429 cluster expression (Taqman assay, p<0.01). In addition, demethylating treatment using 5-aza-dC unmasked miR-200b/a/429 expression in M-typed breast cancer cell lines. Taken together, the finding indicated that the expression of miR-200b/a/429 cluster is epigenetically regulated. Next, we investigated an effect of the miR-200b/a/429 cluster upon cell motility as a function of the EMT. A transfection of exogenous miR-200b/429 inhibited 24% of cell migration ability (Transwell assay). Utilizing microRNA target prediction algorithm, we identified fibronectin as a target gene of miR-200b/429. Utilizing several prediction algorithms for microRNA target genes, we identified fibronectin as a target gene of miR-200b/429. A luciferase-based reporter assay demonstrated that miR-200b/429 were directly associated with fibronectin-3'UTR and repressed 21% (p<0.0001) of the reporter gene expression post-transcriptionally. Conclusion: The promoter hypermethylation of miR-200b cluster is associated with epithelial-mesenchymal transition, and stimulates cell motility by upregulating fibronectin expression in mesenchymal-phenotype breast cancer cells.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P1-02-09.

Flow of a single magnetic vortex in a submicron-size superconducting Al disk controlled by radio-frequency currents

We report the first observation of a single-vortex flow in a mesoscopic superconductor. A flow of a single vortex is successfully controlled by an rf current superimposed on a dc current, evidence of which is provided by voltage steps in current-voltage (I-V) characteristics. Irrespective of the number of vortices confined to the disk, we unambiguously observe that when a single vortex inside the disk is driven out of the disk, another vortex enters the disk similarly to two balls colliding in billiards: only one vortex passes through the Al disk at the same time in mesoscopic systems.

Progressive atrophy of the cerebrum in 2 Japanese sisters with microcephaly with simplified gyri and enlarged extraaxial space

This is a case report that describes 2 sisters with microcephaly, simplified gyri, and enlarged extraaxial space. Clinical features of the cases include dysmorphic features, congenital microcephaly, failure of postnatal brain growth, neonatal onset of seizures, quadriplegia, and severe psychomotor delay. Neuroradiological imaging demonstrated hypoplasia of bilateral cerebral hemispheres with enlarged extraaxial spaces, simplified gyral patterns without a thickened cortex, hypoplastic corpus callosum, and enlarged lateral ventricles, with a reduction in gray and white matter volume during the prenatal and neonatal periods. Repeat MRI revealed progressive atrophy of the cerebral gray and white matter, with enlarged lateral ventricles, although the sizes of the bilateral basal ganglia, thalamus, and infratentorial structures were relatively preserved. These neuroradiological findings imply that this disease is caused by the gene involved in neuronal and glial proliferation in the ventricular zone and in tangential neuronal migration from the ganglionic eminence. The nature of the progressive degeneration of the hemispheric structures should be clarified.

Proposed dose equivalence between clonazepam and pramipexole in patients with restless legs syndrome

BACKGROUND

Dopamine agonists are accepted as the first-line medications for restless legs syndrome (RLS). In some Asian countries, clonazepam is one of the prevalent medications for RLS because of its effect on sleep disturbances. To date, there have not been any studies that examined equivalent doses of pramipexole and clonazepam. To evaluate equivalent doses of pramipexole and clonazepam in RLS, we investigated the efficacy and tolerability after conversion from clonazepam to pramipexole, and examined dose equivalence between the two prescriptions.

METHODS

In a prospective, open-label, multicenter study, 26 RLS patients treated with clonazepam (mean age: 69.2+/-11.0years old) were enrolled and then rapidly switched to pramipexole using a conversion calculation of 4:1 for daily doses. Then the daily dose of pramipexole was up titrated or tapered by 0.125mg/day at each subsequent examination. RLS symptoms and daytime somnolence were evaluated using the International RLS Study Group rating scale (IRLS), Clinical Global Impressions - Severity of illness (CGI-S) and the Epworth Sleepiness Scale (ESS), respectively.

RESULTS

Conversion from clonazepam to pramipexole resulted in significant reductions of IRLS (16.3+/-8.7 to 9.1+/-6.3) and ESS (6.5+/-4.2 to 4.4+/-3.2). CGI scores demonstrated improvement after conversion. In 4 patients (15%), adverse events such as somnolence, sensation of oppression in the lower limbs, diarrhea, or nausea were present. Correlation analysis demonstrated a significant relationship between these daily doses. Spearman's correlation coefficient was 0.662. Our study, however, has some limitations since it is an open-label trial and includes only 26 patients. Further studies using a double-blind design or a crossover design are recommended.

CONCLUSIONS

Statistical analysis demonstrated a 4:1 conversion for clonazepam to pramipexole. When switchover from clonazepam to pramipexole is done, this conversion ratio may be helpful to determine the initial dose of pramipexole for treating RLS.

The cytokine and chemokine profiles in rhabdomyolysis in a patient with Gaucher disease type II

This report describes a patient with Gaucher disease type II who developed severe rhabdomyolysis. We treated him successfully and measured various cytokine and chemokine levels sequentially to elucidate the pathophysiology of rhabdomyolysis. The serum levels of interleukin-6, -8, -10, granulocyte colony-stimulating factor, interferon-gamma, and monocyte chemoattractant protein-1 were markedly elevated in the early phase of rhabdomyolysis. These findings indicate that cytokines and chemokines are related to the massive myolysis and regenerating process. A viral infection may have triggered rhabdomyolysis through exaggerated activation of macrophages in our patient. The profiles of cytokines and chemokines should be examined in further cases to increase our understanding of the pathophysiology of rhabdomyolysis.

Mmp-20 and Klk4 cleavage site preferences for amelogenin sequences

Mmp-20 and Klk4 are the two key enamel proteases. Can both enzymes process amelogenin to generate the major cleavage products that accumulate during the secretory stage of amelogenesis? We isolated Mmp-20 and Klk4 from developing pig teeth and used them to digest the tyrosine-rich amelogenin polypeptide (TRAP), the leucine-rich amelogenin protein (LRAP), and 5 fluorescence peptides. We characterized the digestion products by LC-MSMS, SDS-PAGE, and C18 RP-HPLC monitored with fluorescence and UV detectors. Mmp-20 cleaves amelogenin sequences after Pro(162), Ser(148), His(62), Ala(63), and Trp(45). These cleavages generate all of the major cleavage products that accumulate in porcine secretory-stage enamel: the 23-kDa, 20-kDa, 13-kDa, 11-kDa, and 6-kDa (TRAP) amelogenins. Mmp-20 cleaves LRAP after Pro(45) and Pro(40), producing the two LRAP products previously identified in tooth extracts. Among these key cleavage sites, Klk4 was able to cleave only after His(62). We propose that Mmp-20 alone processes amelogenin during the secretory stage.

Efficacy of continuous acyclovir infusion in neonatal herpes virus encephalitis

We have successfully eliminated herpes simplex virus-2 from the central nervous system in a case of neonatal herpes simplex virus encephalitis with a continuous acyclovir infusion. A male infant delivered from a healthy 22-year-old woman without genital or systemic herpes symptoms around delivery began to develop fever and intractable seizures. He was started on intermittent intravenous acyclovir (20 mg/kg every 8 h) based on the diagnosis of herpes encephalitis. The virus was not eliminated with intermittent acyclovir and vidarabine, while continuous acyclovir was ultimately effective in eliminating herpes simplex virus from his central nervous system. This report demonstrates the efficacy of continuous acyclovir infusion in neonatal herpes simplex virus encephalitis.

Bilateral synchronous spindle cell, apocrine and scirrhous carcinoma breast cancer in a case or malignant lymphoma

An unusual case of synchronous bilateral breast cancer occurring during combination chemotherapy and radiation to the outside of the breast for malignant lymphoma is reported. Two histologically rare carcinomas, spindle cell carcinoma and apocrine carcinoma, were observed in this case. A 77-year-old woman, who had been treated for stage IIIA non-Hodgkin's lymphoma, developed bilateral breast tumors. Aspiration biopsy cytology findings of the tumor in the left breast showed several clusters of adenocarcinoma cells and some large atypical spindle shaped cells, which suggested spindle cell carcinoma. The cytologic findings of the right breast tumor were highly suggestive of scirrhous carcinoma. A modified radical mastectomy was performed on both breasts. Pathological examination disclosed two separate cancer lesions in the left breast. The lesion which had been detected before the operation, was a spindle cell carcinoma. Another lesion, detected for the first time by pathological examination, was an apocrine carcinoma. The lesion in the right breast was a scirrhous carcinoma. Since non-invasive foci were detected in these three cancer lesions, each lesion was thought to be a primary cancer. All dissected bilateral axillary lymph nodes showed malignant lymphoma. Immuno-histochemistry of the spindle cell carcinoma revealed positive immunoreactivity for cytokeratin, which suggested the epithelial as well as mesenchymal nature of this tumor. Synchronous existence of malignant lymphoma and three independent breast cancers including spindle cell carcinoma and apocrine carcinoma is very rare.

Side population cells expressing ABCG2 in human adult dental pulp tissue

AIM

To investigate the presence of side population (SP) cells by the Hoechst exclusion method in human adult dental pulp tissue.

METHODOLOGY

Human adult dental pulp-derived cells were generated from third molar teeth. The cells were stained with Hoechst 33342 and sorted into SP cells or non-SP cells [main population (MP) cells]. Both cell types were compared with cell growth and RT-PCR analyses.

RESULTS

SP cells that express ABCG2, Nestin, Notch-1 and alpha-smooth muscle actin were found at frequencies ranging from 0.67% to 1.02%. This SP profile disappeared in the presence of verapamil. These SP cells expressed dentine sialophosphoprotein and dentine matrix protein-1 when cultured in osteogenic medium.

CONCLUSION

Human adult dental pulp tissue contains SP cells that differentiate into odontoblast-like cells.

[The efficacy of perioperative administration of steroid and erythromycin in the surgery for lung cancer complicated with interstitial pneumonia]

OBJECTIVES

We evaluated the efficacy of perioperative administration of steroid and erythromycin in surgery for lung cancer complicated with interstitial pneumonia (IP) to prevent postoperative acute exacerbation.

PATIENTS AND METHODS

We operated on 21 lung cancer patients with IP for 10 years. The patients were given 400 mg of erythromycin over 1 week before surgery and re-administered on the 1st operative day. The patients were also given 125 mg of methylprednisolone intravenously just before operation and continued until the 2nd operative day.

RESULTS

Lobectomy was performed in 16, segmentectomy or partial resection in 2 each, and completion pneumonectomy in 1. Three patients developed acute exacerbation of IP, but it occurred after the re-operation due to postoperative complications in 2. We experienced no operative death within 30 days, however, 2 died during the hospital stay due to multiple organ failure and sepsis. Seven of 21 patients had postoperative complications; air leakage over 1 week in 4, arrhythmia in 3, and atelectasis, postoperative bleeding, and pneumonia in 1 each, the morbidity rate was 33%.

CONCLUSIONS

We conclude that the administration of steroid and erythromycin in surgery for lung cancer with IP was suspected the usefulness to prevent a postoperative acute exacerbation of IP.

Dissimilatory iodate reduction by marine Pseudomonas sp. strain SCT

Bacterial iodate (IO(3)(-)) reduction is poorly understood largely due to the limited number of available isolates as well as the paucity of information about key enzymes involved in the reaction. In this study, an iodate-reducing bacterium, designated strain SCT, was newly isolated from marine sediment slurry. SCT is phylogenetically closely related to the denitrifying bacterium Pseudomonas stutzeri and reduced 200 microM iodate to iodide (I(-)) within 12 h in an anaerobic culture containing 10 mM nitrate. The strain did not reduce iodate under the aerobic conditions. An anaerobic washed cell suspension of SCT reduced iodate when the cells were pregrown anaerobically with 10 mM nitrate and 200 microM iodate. However, cells pregrown without iodate did not reduce it. The cells in the former category showed methyl viologen-dependent iodate reductase activity (0.31 U mg(-1)), which was located predominantly in the periplasmic space. Furthermore, SCT was capable of anaerobic growth with 3 mM iodate as the sole electron acceptor, and the cells showed enhanced activity with respect to iodate reductase (2.46 U mg(-1)). These results suggest that SCT is a dissimilatory iodate-reducing bacterium and that its iodate reductase is induced by iodate under anaerobic growth conditions.

Translocation and insertion of an amphiphilic polymer

Translocation of amphiphilic polymers (random and block copolymers), consisting of hydrophilic and hydrophobic monomers, threading a pore is studied by using a three-dimensional dynamic Monte Carlo simulation. We find that there is a "translocation-insertion" threshold in the fraction of hydrophobic monomers on an amphiphilic polymer. The translocation time is given by simple scaling laws and increases with increasing the fraction of hydrophobic monomers.

Attitudes about chemotherapy for Japanese patients with or without cancer: Doctors, nurses, and the general public

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Background: A prospective survey in England demonstrated that patients with cancer were much more likely to accept radical treatment with minimal chance of benefit than people who did not have cancer (Slevin et al. Br Med J 1990; 300: 1458–60). We compared responses of Japanese patients with cancer with those of a control group of physicians, nurses, and patients without cancer in assessing personal cost-benefit of chemotherapy using the same questionnaire with Slevin's study. Methods: Subjects were asked with questionnaires whether of not to accept intensive and mild chemotherapy with a supposed minimum chance of effectiveness. 153 patients with cancer, 265 controls, 213 doctors, 397 nurses, and 51 patients without cancer were subjects of the study. Results: Percentage of subjects who accepted intensive chemotherapy with a supposed minimum chance of effectiveness (1% chance of cure, 3-month prolonging life, 1% relief of symptoms) by subject group were as follows: cancer patients; 62/55/52, doctors; 27/32/4, nurses; 11/12/5, non-cancer patients; 35/40/36, controls; 23/24/15, respectively. Conclusions: More patients with cancer than people without cancer accepted treatments giving the minimal benefit for cure, prolonging life or palliation of symptoms. Interestingly, the results in Japanese survey were similar to the previous study in England.

No significant financial relationships to disclose.

Clinical pictures of 75 patients with neonatal intrahepatic cholestasis caused by citrin deficiency (NICCD)

We clarified the clinical features of NICCD (neonatal intrahepatic cholestasis caused by citrin deficiency) by retrospective review of symptoms, management and long-term outcome of 75 patients. The data were generated from questionnaires to paediatricians in charge of the patients. Thirty of the patients were referred to hospitals before 1 month of age because of positive results in newborn screening (hypergalactosaemia, hypermethioninaemia, and hyperphenylalaninaemia). The other 45, the screen-negative patients, were referred to hospitals with suspected neonatal hepatitis or biliary atresia because of jaundice or discoloured stool. Most of the screen-negative patients presented before 4 months of age, and 11 had failure to thrive. Laboratory data showed elevated serum bile acid concentrations, hypoproteinaemia, low levels of vitamin K-dependent coagulation factors and hypergalactosaemia. Hypoglycaemia was detected in 18 patients. Serum amino acid analyses showed significant elevation of citrulline and methionine concentrations. Most of the patients were given a lactose-free and/or medium-chain triglyceride-enriched formula and fat-soluble vitamins. Symptoms resolved in all but two of the patients by 12 months of age. The two patients with unresolved symptoms suffered from progressive liver failure and underwent liver transplantation before their first birthday. Another patient developed citrullinaemia type II (CTLN2) at age 16 years. It is important to recognize that NICCD is not always a benign condition.

A Phase I Dose Escalation Study of Weekly Docetaxel and Carboplatin in Elderly Patients With Nonsmall Cell Lung Cancer

OBJECTIVE

We conducted a phase I dose escalation study to determine the maximum tolerated dose (MTD), the recommended dose (RD), and the safety profile of a weekly docetaxel and carboplatin combination regimen in the treatment of elderly patients with advanced nonsmall cell lung cancer (NSCLC).

PATIENTS AND METHODS

Chemotherapy-naive patients with stage IIIB and IV NSCLC, >70 years of age, performance status (ECOG) 0-2, with adequate bone marrow, renal, liver and cardiac function, were treated with docetaxel and carboplatin. Docetaxel was given at escalated doses starting from 20 mg/m2/wk on days 1, 8, and 15, with an increment of 5 mg/m2 followed by carboplatin also administered at escalated doses starting from AUC 4 to 6 (mg/ml/min); the regimen was administered every 4 weeks. The dose limiting toxicity (DLT) of the regimen was assessed during the first chemotherapy cycle.

RESULTS

There were 25 patients enrolled in this study and assessed for safety. Neutropenia was the main DLT of the regimen; grade 3/4 neutropenia occurred in 5 patients (20%). Hematologic toxicities were mild, and included grade 3 thrombocytopenia in 1 patient (4%) and grade 3 anemia in 1 patient (4%). Nonhematologic toxicities were generally mild, and included grade 3 constipation in 1 patient (4%) and grade 3 renal disorder in 1 patient (4%). Objective responses were seen in 9 patients (response rate 36%).

CONCLUSIONS

The MTD was carboplatin AUC 5 on day 1 and docetaxel 30 mg/m2 on days 1, 8, and 15; therefore, the RD for the phase II study is carboplatin AUC 5 and docetaxel 30 mg/m2. The combination of docetaxel and carboplatin is a feasible and well-tolerated regimen for the treatment of elderly patients with advanced NSCLC. This regimen merits further investigation in phase II trials.

Asymmetric Total Synthesis of (+)-K01-0509 B: Determination of Absolute Configuration

K01-0509 B is a novel natural product which contains a carbamoylated cyclic guanidine. Our asymmetric total synthesis features a Sharpless asymmetric epoxidation and a stereocontrolled construction of the cyclic guanidine via an asymmetric nitroaldol reaction, followed by intramolecular SN2 cyclization. These reactions allowed the cyclic guanidine and the adjacent hydroxy group to be assembled, facilitating the asymmetric total synthesis and determination of the absolute stereochemistry of K01-0509 B. [reaction: see text].