PD01-05: Histone Deacetylase Inhibitor LBH589 (Panobinostat) Suppresses the Activated-NFκB Pathway in Acquired Aromatase Inhibitor Resistant Breast Cancer Cells

Background: Aromatase inhibitors (AIs) are effective in treating postmenopausal patients with estrogen receptor (ER)-positive breast cancer. However, resistance to endocrine therapies remains a major problem in the management of ER-positive breast cancer. Recently, histone deacetylase inhibitors (HDACis) show promise as cancer therapeutics, but the full scope of their utility remains unknown.

Experimental Design: In order to search for critical genes in developing resistance to AI, a microarray study was performed on AI resistant cells derived from MCF-7aro cells that overexpress aromatase and on AI resistant tumors from our mouse experiments. Moreover, using MCF-7aro cells that are resistant to anastrozole (Ana-R), letrozole (Let-R), and exemestane (Exe-R), as well as LTEDaro, we evaluated the significance of NFKB1 and several regulatory genes in AI resistance, and the anti-NFκB1 activity of HDACi LBH589 in vitro and in vivo.

Results: Significant changes (Fold change cutoff > 1.5, false discovery rate < 0.05) in the expression levels of 22 genes among three networks were identified from microarray analysis of our in vitro and in vivo models of acquired AI resistance. NFKB1 is a key player in one of three networks, including 11 genes, and is functionally up-regulated in all AI resistant cells. NFκB1 knockdown suppresses the proliferation of AI resistant cells more than that of MCF-7aro cells. Moreover, AI resistant cell lines are highly sensitive to LBH589 treatment and apoptosis is induced in these cell lines. LBH589 suppressed NFκB1 as demonstrated at both the mRNA and protein levels in LTEDaro and other AI resistant cell lines. Furthermore, the LBH589 treatment abrogated tumor growth in mice, and was associated with significant decreased levels of NFKB1 in tumors.

Conclusions: Our findings provide new insights into how the NFκB1-mediated networks play roles in AI resistance, and strongly support that LBH589 offers a novel therapeutic strategy for patients with AI resistant breast cancer.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr PD01-05.

Genome-wide association study on bipolar disorder in the Bulgarian population

Bipolar disorder is a severe psychiatric disorder influenced by environmental and genetic factors. Genetic studies have implicated many variants in the disease's etiology but only few have been successfully replicated. We conducted a genome-wide association study (GWAS) on bipolar disorder in the Bulgarian population followed by a replication study of the top 100 single nucleotide polymorphisms (SNPs) showing the smallest P values. The GWAS was performed on 188 bipolar disorder patients and 376 control subjects genotyped on the Illumina 550 platform. The replication study was conducted on 122 patients and 328 controls. Although our study did not show any association P value that achieved genome-wide significance, and none of the top 100 SNPs reached the Bonferroni-corrected P value in the replication study, the plausible involvement of some variants cannot be entirely discarded. Three polymorphisms, rs8099939 [P = 2.12 × 10(-6), odds ratio (OR) = 1.95, 95% confidence interval (CI) = 1.43-2.67] in GRIK5, rs6122972 (P = 3.11 × 10(-6), OR = 2.02, 95% CI = 1.46-2.80) in PARD6B and rs2289700 (P = 9.14 × 10(-6), OR = 2.13, 95% CI = 1.53-2.95) in CTSH remained associated at a similar level after Mantel-Haenszel test for combining the results from the genome-wide and replication studies. A modest association was also detected for SNP rs1012053 (GWAS P = 4.50 × 10(-2)) in DGKH, which has already been reported as the most significant variant in a previous genome-wide scan on bipolar disorder. However, further studies using larger datasets are needed to identify variants with smaller effects that contribute to the risk of bipolar disorder.

Common variant in 6q26-q27 is associated with distal colon cancer in an Asian population

BACKGROUND AND AIM

Colorectal cancer (CRC) is a multifactorial disease with both environmental and genetic factors contributing to its development. The incidence of CRC is increasing year by year in Japan. Patients with CRC in advanced stages have a poor prognosis, but detection of CRC at earlier stages can improve clinical outcome. Therefore, identification of epidemiologial factors that influence development of CRC would facilitate the prevention or early detection of disease.

METHODS

To identify loci associated with CRC risk, we performed a genome-wide association study (GWAS) for CRC and sub-analyses by tumour location using 1583 Japanese CRC cases and 1898 controls. Subsequently, we conducted replication analyses using a total of 4809 CRC cases and 2973 controls including 225 Korean subjects with distal colon cancer and 377 controls.

RESULTS

We identified a novel locus on 6q26-q27 region (rs7758229 in SLC22A3, p = 7.92 × 10⁻⁹, OR of 1.28) that was significantly associated with distal colon cancer. We also replicated the association between CRC and SNPs on 8q24 (rs6983267 and rs7837328, p = 1.51 × 10⁻⁸ and 7.44 × 10⁻⁸, ORs of 1.18 and 1.17, respectively). Moreover, we found cumulative effects of three genetic factors (rs7758229, rs6983267, and rs4939827 in SMAD7) and one environmental factor (alcohol drinking) which appear to increase CRC risk approximately twofold.

CONCLUSIONS

We found a novel susceptible locus in SLC22A3 that contributes to the risk of distal colon cancer in an Asian population. These findings would further extend our understanding of the role of common genetic variants in the aetiology of CRC.

Relationship between prefrontal cortex blood flow and mayer wave during the performance of the original version trail making test

Objectives

We measured mayer wave in the prefrontal cortex during the performance of original version TMT by multichannel NIRS using sensitive for detecting changes of oxyHb.

Methods

Sixteen healthy student volunteers performed four different screens of TMT-A, and then two different screens of TMT-B.

Results

Mayer wave changed while in the prefrontal cortex during the performance of TMT-A and TMT-B. The changes were prominent during the TMT performed. Mayer wave changed in the rear prefrontal cortex during TMT.

Additional measurements and to present a detailed database.

Conclusion

Meyer wave reflects brain activity. You should consider in more detail.

Differences between risk factors among irritable bowel syndrome subtypes in Japanese adults

BACKGROUND

Irritable bowel syndrome (IBS) is a common gastrointestinal disease. Detailed clinical characteristics of patients with different IBS subtypes have not been well established. Our aim was to examine the prevalence and risk factors of IBS and its subtypes in Japanese adults.

METHODS

We performed a cross-sectional study of Japanese workers who visited a clinic for a routine health check-up and asked them to fill out a self-report questionnaire. Irritable bowel syndrome and its subtypes were defined by ROME III criteria. A logistic regression model was used to identify risk factors.

KEY RESULTS

Irritable bowel syndrome was present in 367 (13.5%) of 2717 eligible subjects; 79 had IBS with constipation (IBS-C); 102 had IBS with diarrhea (IBS-D); 89 had mixed IBS (IBS-M); and 97 had unsubtyped IBS (IBS-U). Irritable bowel syndrome was significantly associated with young age [odds ratio (OR) = 0.87, 95% confidence interval (CI) 0.80-0.95], female gender (OR = 1.78, 95% CI 1.38-2.29), low body mass index (BMI) (OR = 0.95, 95% CI 0.92-0.99), and the presence of allergic disease (OR = 2.19, 95% CI 1.40-3.54). Analysis of IBS subtypes revealed that IBS-C was associated with young age and female gender; IBS-D with young age, low BMI, and drinking habit; IBS-M with female gender, smoking habits, and allergic diseases; and IBS-U with age, female gender, and allergic diseases.

CONCLUSIONS & INFERENCES

Irritable bowel syndrome was common and associated with young age, female gender, low BMI, and presence of allergic diseases in Japanese adults. Several differences were noted between the risk factors among different IBS subtypes.

Multifocal granulomatous jejunitis associated with an argyrophilic gram-positive segmented filamentous bacterium in a Holstein cow

Multifocal, raised, ulcerated firm nodules accompanied by an intussuscepted area were detected in the jejunum of an 8-year-old Holstein cow. The cut surfaces of the nodules were yellow-white. Microscopically, the lamina propria was expanded by an intense infiltration of epithelioid cells, multinucleate giant cells, macrophages, lymphocytes and neutrophils. Numerous bacteria were found within the granulomatous lesions. These were argyrophilic, gram-positive, periodic acid-Schiff-positive, segmented, rarely branched, elongate filamentous bacteria (2-28 μm in length, 0.2-0.35 μm in diameter). Ultrastructurally, a cell wall with an electron-transparent zone was detected. The present pathogen was clearly different from the argyrophilic, gram-negative, non-segmented, filamentous bacterium previously reported in a Holstein cow with jejunal granuloma. Comparative 16S rDNA gene sequencing analysis revealed that the organism was an unpublished species (GenBank accession number AB539875). This is the first report of bovine jejunal granuloma associated with an argyrophilic gram-positive segmented filamentous bacterium.

36 CHANGES IN PLASMA CONCENTRATIONS OF PROGESTERONE AND ESTROGENS DURING GESTATION IN COWS WITH STILLBORN SOMATIC CELL CLONED CALVES

Cloning of mammals by nuclear transfer frequently results in gestational or neonatal failure with a variety of abnormalities that are likely caused by inappropriate epigenetic reprogramming. Early diagnosis of fetal abnormality is important for efficient production of cloned animals. Sex steroids are produced in the bovine placenta and their levels in the blood might be useful as a measure of fetal well being, as they are in humans. The objective of this study was to investigate whether changes in peripheral concentrations of progesterone and estrogens reflect fetal conditions. Donor cells for nuclear transfer were obtained from subculture of cumulus cells retrieved from ovarian follicles of a Japanese Black cow. Recipient oocytes were derived from ovaries obtained at an abattoir and matured in vitro. Metaphase II oocytes were enucleated and each fused with a donor cell by DC pulses. Nuclear transferred oocytes were activated and cultured for 7 days. Embryos developed to the blastocyst stage were transferred into the uterine horn ipsilateral to the ovary bearing the CL of 29 multiparous Japanese Black and Holstein crossbred cows at 7 to 8 days after the day of standing oestrus (Day 0). Blood was collected at regular intervals from Day 40 until parturition. Plasma progesterone, estrone, oestradiol-17β, and estrone sulfate were measured by RIA in 4 recipient cows. 2 vaginally delivered healthy calves weighed 35 and 36 kg on days 278 and 280, respectively. The other 2 delivered stillborn calves weighed 42 and 31 kg by Caesarean section on days 267 and 287, respectively. Steroid profiles were compared with each other and with those in a cow made pregnant by embryo transfer. Statistical differences at stages of gestation were analysed with repeated-measures ANOVA. Stillborn calves were subjected to necropsy and histopathological analysis. Significant differences in steroid levels were observed individually and temporarily. In the cow bearing the former stillborn, progesterone and oestradiol-17β concentrations tended to be lower during mid and late gestation, respectively. Large offspring syndrome, ventricular septal defect, pulmonary oedema, hepatic fibrosis, and placental dysplasia were found in the calf by necropsy and histopathological analysis. In the cow bearing the second stillborn, plasma progesterone concentrations were temporarily increased from days 220 to 230 and reached a peak of 16 ng mL–1, which was approximately 3 times as high as before (5.0 ± 0.9; mean ± s.d.), then followed by a similar transient increase in estrogens during days 240 and 250 (170 pg mL–1, 16 pg mL–1, and 21 ng mL–1 at peak of estrone, oestradiol-17β, and estrone sulfate, respectively). Thereafter, oestrogen concentrations stayed low until parturition. As internal organs of the stillborn calf were severely autolysed with polyhydramnios at birth, the fetus might have been dead around Day 250. These results imply that changes in peripheral steroid concentrations in some cases reflect fetal condition.

Abstract P2-02-08: 3-Tesla MRI Is More Useful for the Evaluation of Intraductal Spreading Area of Breast Cancer: A Comparative Study with Conventional 1.5-Tesla MRI

Background: High quality of space and temporal resolution is demanded from the diagnosis for intraductal spreading area of breast cancer. In our hospital, from April 2007, 3-Tesla (T) MRI was transduced and high resolution dynamic studies for bilateral mammary have been performed. We have reported the accuracy of 3-T MRI in the evaluation of intraductal spreading area of breast cancer at 31st SABCS. At this time, we demonstrate our follow-up data.

Methods: We assessed 256 patients with primary breast cancer who underwent the 3-T or 1.5-T breast MRI as pre-operative examination between April, 2007 and February, 2010. Concerning the diagnosis of intraductal spreading area of breast cancer, we weighed 3-T MRI against conventional 1.5-T MRI. Using 1.5-T or 3-T MRI (Achieva, Philips), we injected contrast medium (Magnepist) with 0.2ml/kg body weight in 1ml/sec and photographed five aspects before injection and after injection for every 90 seconds.

We obtained fat-sat T1-weighted magnetic resonance image (T1WI), multi-planar reconstruction (MPR) image and standard maximum intensity projection (MIP) image based on T1WI by coronal section, and furthermore slab MIP image with Aquerius net (Terarecon), and we evaluated the enhanced area.

Results: 138 cases were examed with 1.5-T MRI, and 118 cases with 3-T MRI. In 1.5-T group, 40 cases (30%) were underestimated, additional resection were required intraoperativelly with cancer-cells positive surgical margin in 18 cases (13%), and surgical margin was positive with carcinoma cells by final pathological findings in 12 cases.

In two patients we were forced to changes from breast-conserving surgery to mastectomy, and two cases underwent reoperation (mastectomy) with the diagnosis of widely positive surgical margin. In comparison with 1.5-T MRI group, 16 cases (14%) were underestimated in 3-T MRI group, intraoperative addition resection in eight cases (7%), and surgical margin positive by the final pathological findings in 13 cases, respectively.

Conclusions: The concern to enhance an artifact is known on 3-T MRI because it has high resolution. However, it may be more useful rather than1.5-T MRI because of its high resolution, to evaluate the intraductal spreading area of breast cancer and to determine the extent of surgical resection.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P2-02-08.

Intracranial dural arteriovenous fistula with retrograde cortical venous drainage: use of susceptibility-weighted imaging in combination with dynamic susceptibility contrast imaging

BACKGROUND AND PURPOSE

SWI is a new MR imaging method that maximizes sensitivity to magnetic susceptibility effects with phase information for visualizing small cerebral veins. The purpose of this study was to report the use of SWI in combination with DSC in examining related RCVD in patients with intracranial DAVFs.

MATERIALS AND METHODS

Ten patients with angiographically confirmed DAVFs with RCVD underwent conventional MR imaging, SWI, and DSC. The ability of SWI to depict dilated cerebral veins was evaluated and then compared with DSC. The hemispheres of patients with DAVFs were grouped into affected (with RCVD) or nonaffected (without RCVD) categories by angiography. Four patients had bilaterally affected hemispheres. A total of 14 affected hemispheres in patients with DAVFs with RCVD were evaluated.

RESULTS

SWI showed dilated cerebral veins on the surface of the brain in all (100%) of the 14 affected hemispheres in patients with DAVFs with RCVD and deep in the brain in 9 (64%). T2-weighted imaging showed prominent flow-voids on the surface of the brain in 10 (71%) of the 14 affected hemispheres in patients with DAVFs with RCVD and deep in the brain in 5 (36%). DSC showed increased cerebral blood volume in all of the 14 affected hemispheres. The SWI findings regarding dilated veins on the surface of the brain corresponded well with the areas of increased cerebral blood volume.

CONCLUSIONS

SWI in combination with DSC could be used to characterize the presence of RCVD in patients with DAVFs.

Lawsonia intracellularis and virulent Rhodococcus equi infection in a thoroughbred colt

A 26-month-old thoroughbred colt with a 4-month history of continuous diarrhoea and weight loss was subject to necropsy examination. The small intestinal mucosa was thickened and this change particularly affected the terminal ileum. Microscopical examination revealed multifocal epithelial hyperplasia, with multifocal granulomas and marked lymphocytic infiltration of the lamina propria. Numerous gram-negative argyrophilic curved bacilli were observed within the cytoplasm of affected enterocytes. Macrophages and epithelioid cells forming the granulomas had abundant, lightly eosinophilic, foamy cytoplasm, with occasional large, clear vacuoles containing gram-positive coccobacilli. Immunohistochemical studies suggested that the argyrophilic bacilli were Lawsonia intracellularis and the gram-positive coccobacilli were Rhodococcus equi. L. intracellularis-specific DNA fragments were amplified from the affected ileocaecal mucosa by polymerase chain reaction. Virulent R. equi (VapA positive) was isolated in pure culture from the liver and mesenteric lymph nodes. These results suggested that the two intracytoplasmic organisms had induced multifocal proliferative and granulomatous enteritis accompanied by severe and extensive lymphocytic infiltration.

Basic study of brain injury mechanism caused by cavitation

The purpose of this study is to discuss the mechanism of brain injury experimentally, with respect to the pressure changes on the surface of a brain agar phantom by cavitation. First, an experimental system to perform an impact experiment is presented. We present some images taken by a high-speed camera of the behavior of a simple physical head model with and without the brain agar phantom during impact. From the photographs of the high-speed camera, we can confirm that cavitation bubbles occur at the contrecoup side, irrespective of the usage of the brain agar phantom. Second, two experimental systems to perform impact and strike experiments are presented. The pressure changes on the surface of the brain agar phantom at contrecoup side were measured by two kinds of experiments and impact velocities. Frequency analysis of the measured pressure changes was conducted by FFT software. From these results, we found that the collapse of cavitation bubbles at the contrecoup side can strongly affect the characteristics of pressure changes on the surface of the brain agar phantom.

Meningoencephalitis associated with Sarcocystis spp. in a free-living Japanese raccoon dog (Nyctereutes procyonoides viverrinus)

A free-living, young adult, male Japanese raccoon dog (Nyctereutes procyonoides viverrinus) was rescued in Gifu, Japan in March 2009. The animal was weak and emaciated with neurological signs that included head tilt, tremor and tic. The brain showed no gross abnormality at necropsy, but microscopically there was severe meningoencephalitis associated with protozoa, which were morphologically consistent with the asexual developmental stage of Sarcocystis spp. The protozoa were immunohistochemically negative for Toxoplasma gondii and Neospora caninum, but reacted weakly with antiserum specific for Sarcocystis cruzi. Analysis of the partial 18S rRNA gene sequence revealed that the protozoa were most closely related to an unidentified Sarcocystis species that was isolated from the white-fronted goose (Anser albifrons).

Oestrogen receptor-alpha contributes to the regulation of the hedgehog signalling pathway in ERalpha-positive gastric cancer

BACKGROUND

Oestrogen receptor-alpha (ERalpha) is highly expressed in diffuse-type gastric cancer and oestrogen increases the proliferation of ERalpha-positive gastric cancer. However, a detailed mechanism by which oestrogen increases the proliferation of these cells is still unclear.

METHODS

We used 17-beta-oestradiol (E2) as a stimulator against the ERalpha pathway. Pure anti-oestrogen drug ICI 182 780 (ICI) and small interfering RNA against ERalpha (ERalpha siRNA) were used as inhibitors. Cyclopamine (Cyc) was used as the hedgehog (Hh) pathway inhibitor. Two human ERalpha-positive gastric cancer cells were used as target cells. Effects of the stimulator and inhibitor on E2-induced cell proliferation were also examined.

RESULTS

In ERalpha-positive cells, E2 increased not only cell proliferation but also one of the ligands of the Hh pathway, Shh expression. 17-beta-Oestradiol-induced cell proliferation was suppressed by ICI, ERalpha siRNA or Cyc. The increased expression of Shh induced by E2 was suppressed by ICI and ERalpha siRNA but not by Cyc. Furthermore, recombinant Shh activated the Hh pathway and increased cell proliferation, whereas anti-Shh antibody suppressed E2-induced cell proliferation. When a relationship between ERalpha and Shh expressions was analysed using surgically resected gastric cancer specimens, a positive correlation was found, suggesting a linkage between the ERalpha and Hh pathways.

CONCLUSION

Our data indicate that activation of the ERalpha pathway promotes cell proliferation by activating the Hh pathway in a ligand-dependent manner through Shh induction of ERalpha-positive gastric cancer.