Abstract 1972: Identification of novel candidate driver genes of colorectal cancer on chromosome 7p

Background

Colorectal cancer (CRC) is one of the most prevalent types of cancer. The high mortality rate of CRC is a serious problem. Hence it is urgently necessary to identify novel molecular target to improve the mortality rate. Amplification of chromosome 7p is frequent in CRC, and it has been considered to harbor driver genes that promote tumorigenesis or tumor progression by the gain of function. The aim of this study is to identify novel candidate driver genes on chromosome 7p and to clarify the clinical significance of their expression in CRC.

Material and Methods

1. We selected the candidate genes that satisfied the following criteria using CRC data from The Cancer Genome Atlas (TCGA). 1) The DNA copy number and mRNA expression is positively correlated with each other, 2) overexpressed in the tumor tissues compared to the normal tissues. 2. The mRNA expression of the candidate genes was measured in 108 surgically-resected CRC tissues and the paired normal tissues in our hospital by quantitative RT-PCR. The differences of mRNA expression between CRC tissues and normal tissues were analyzed by Mann Whitney U-test. 3. Survival analysis between high and low expression group of the candidate genes was performed by Kaplan-Meier method. Correlation between the mRNA expression of the candidate genes and the clinicopathological factors were analyzed by Fisher’s exact test. 4. We performed Gene Set Enrichment Analysis (GSEA) in CRC data from TCGA to clarify the correlation between the candidate genes and gene sets that are associated with tumorigenesis or tumor progression.

Results

DEAD Box Helicase56 (DDX56), ATP-dependent RNA helicases involved in several aspects of RNA metabolism including mRNA splicing and transport, transcription, translation and remodeling of ribonucleoprotein complexes, was satisfied with the criteria. The expression of DDX56 was significantly higher in CRC tissues than in normal colon tissues (p<0.005), and it correlated with lymphatic invasion (p=0.02), and distant metastasis (p=0.03). The high DDX56 expression group had a significantly poorer prognosis than the low expression group (p=0.03). On multivariate analysis, high DDX56 expression was an independent prognostic factor affecting OS (p=0.013) with hazard ratios (95% CI) of 2.32 (1.20-4.48) among clinicopathological factors. GSEA showed that DDX56 expression was positively correlated with mitotic cell cycle progression and spliceosome.

Conclusions

We identified DDX56 as a promising driver gene of CRC on chromosome 7p. DDX56 expression was positively associated with lymphatic invasion and distant metastasis, and was an independent poor prognostic factor. Furthermore, DDX56 may be involved in tumor progression through stimulating cell-cycle. DDX56 could be a therapeutic target as well as a poor prognostic biomarker in CRC.

Note: This abstract was not presented at the meeting.

Citation Format: Yuta Kouyama, Yushi Ogawa, Takaaki Masuda, Yukihiro Yoshikawa, Miwa Noda, Hiroaki Wakiyama, Kuniaki Sato, Sho Nambara, Qingjiang Hu, Shinya Kidogami, Tomoko Saito, Shotaro Sakimura, Naoki Hayashi, Yohsuke Kuroda, Shuhei Ito, Hidetoshi Eguchi, Koshi Mimori. Identification of novel candidate driver genes of colorectal cancer on chromosome 7p [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 1972. doi:10.1158/1538-7445.AM2017-1972

Abstract 5439: The chronological analysis of previously-reported serum microRNA expression in colorectal cancer

Background: Colorectal cancer (CRC) is a major cause of cancer-associated death in the world. Despite surgical resection and pre- and postoperative chemotherapy, recurrence is common in patients with CRC. Many studies have examined potential biomarker of recurrence in CRC in attempt to improve patients’ prognosis. MicroRNAs (miRNAs), the small noncoding RNAs that are associated with the development of cancer, in serum have been shown to be potential biomarkers in various type of cancers and several miRNAs have been reported in colorectal cancer. However, no miRNAs has been applied in a clinical setting because of small amount of each samples. In the present study, we evaluated the clinical effectiveness of previously-reported serum miRNAs expression in CRC using periodically gathered serum.

Materials and Methods: We obtained 328 serum samples, which gathered periodically (preoperative, postoperative one month, three months, six months, one year, and two years), from 71 patients with stageII/III CRC (stageII: 31 patients, stageIII: 40 patients). Thirteen patients had a recurrence. The miRNAs were extracted from serums, and miRNA microarray analysis was performed. Previously-reported sixteen miRNAs (let-7a, miR-15b, miR-18a, miR-19a, miR-21, miR-23a, miR-29a, miR-31, miR-92a, miR-150, miR-181b, miR-203, miR-223, miR-335, miR-1229 and miR-1246) were quantified by microRNA microarray analysis.

Results: In no recurrence cases, preoperative miR-1246 expression is higher than postoperative miR-1246 expression; preoperative; 5.6 ± 1.8, postoperative one month: 4.1 ± 1.6 (p < 0.05), postoperative three months: 3.4 ± 1.9 (p < 0.05) , postoperative six months: 4.8 ± 1.5 (p < 0.05) , postoperative one year: 4.0 ± 1.6 (p < 0.05) , postoperative two years: 4.8 ± 1.5 (p < 0.05). We observed trend of miR-1246 re-elevation before recurrence. The sensitivity and specificity of miR-1246 for detection of CRC are 52.8% and 84.9% (AUC=0.746). This result is almost as same as that of serum CEA which is major tumor marker of CRC (sensitivity: 22-48%, specificity: 63-100%). In our data, the sensitivity of CEA is 38% and the specificity is 94% (cutoff: > 5 ng/ml). The sensitivity and specificity of miR-1246 is higher than of CEA.

Conclusion: Serum miR-1246 are best promising biomarker for CRC because of high sensitivity and specificity. On the other hand, previous reported miRNAs excluding miR-1246 are inadequate as biomarker of CRC in our data. Next we are going to identify novel microRNAs which has higher sensitivity and specificity using our microarray analysis.

Note: This abstract was not presented at the meeting.

Citation Format: Yukihiro Yoshikawa, Mitsuko Fukunaga, Takaaki Masuda, Miwa Noda, Hiroaki Wakiyama, Yuta Koyama, Shinya Kidogami, Kuniaki Sato, Qingjiang Hu, Sho Nambara, Tomoko Saito, Shotaro Sakimura, Naoki Hayashi, Yohsuke Kuroda, Shuhei Ito, Yuichiro Doki, Masaki Mori, Koshi Mimori. The chronological analysis of previously-reported serum microRNA expression in colorectal cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 5439. doi:10.1158/1538-7445.AM2017-5439

Prognostic impact of PD-1, PD-L1, and CD8 genes expression in peripheral blood in gastric cancer

11531

Background: Programmed death 1 (PD-1)/PD-1 ligand (PD-L1) blocking agents to gastric cancer (GC) in the clinical setting show significant therapeutic promise. However, since these agents are enormously expensive and potentially toxic, it is crucial to identify predictive biomarkers for detecting the best candidate who would benefit from these agents by less invasive and simpler method, such as liquid biopsy. Methods: Expression levels of genes coding for PD-1, PD-L1 and CD8 (CD8+ T cells are closely associated with cellular immune responses to tumors) were assessed in peripheral blood (PB) samples using quantitative RT-PCR. Samples were obtained from 407 GC patients (392 patients with neoadjuvant chemotherapy [NAC] and 15 patients without NAC) before surgery and 23 PB from normal controls (NC). Flow cytometric analysis was performed to identify PD-1-expressed cells in PB mononuclear cells. Results: PD-1, PD-L1 and CD8 mRNA levels of GC patients were significantly higher than those of NC: 4.2-, 3.0- and 6.1-fold increases, respectively (P < 0.0001, P = 0.0001 and P < 0.0001). PD-1 mRNA levels were significantly lower in GC patients with NAC than in GC patients without NAC (P < 0.01). GC patients with low PD-1, high PD-L1 and low CD8 mRNA levels had significantly poorer overall survival (OS) than those with high PD-1, low PD-L1 and high CD8 mRNA levels, respectively (P < 0.05, P < 0.05 and P < 0.05). Multivariate analysis showed that PD-1 low/ PD-L1 high mRNA levels was independent risk factors for OS (OR 2.15, 95%CI 1.29-3.45, P < 0.01). Flow cytometric analysis demonstrated the proportion of CD3 (T cell marker)-positive cells in the PD-1-positive fraction were 95.4 ± 6.9% in GC patients. Thus, most PD-1 protein expression occurred on T cells. Taken together, PD-1, PD-L1 and CD8 mRNAs in PB were overexpressed in GC patients, and PD-1 mRNA levels which was mostly expressed on T cells in protein levels in PB were decreased in GC patients with NAC. Furthermore, relative levels of PD-1, PD-L1 and CD8 were associated with prognosis, respectively. Conclusions: Preoperative PD-1, PD-L1 and CD8 mRNA levels in PB may reflect antitumor immune response, and PD-1 low/ PD-L1 high mRNA levels in PB are markers of poor prognosis in GC patients.

Prevalence of Baylisascaris Roundworm in Captive Kinkajous in Japan

Baylisascaris potosis causes larva migrans in animals. The present study evaluated the prevalence of B. potosis in captive kinkajous ( Potos flavus ) and the ability of milbemycin to treat natural infections of B. potosis in 2 female wild-caught kinkajous. In 2012, fecal samples were collected from 16 kinkajous in 6 zoological gardens and 29 imported captive kinkajous from 4 pet traders in Japan. Although all samples from zoological gardens were negative, 8 kinkajous from traders were positive for Baylisascaris eggs, at least 4 of which were wild caught in the Republic of Guyana. No associated human illness was reported from any of the facilities. The 2 infected kinkajous received a single oral administration of Milbemycin® A Tablets, which delivers 0.69-0.89 mg/kg milbemycin oxime. Fecal examinations on days 14 and 30 were negative for Baylisascaris eggs. These results demonstrated that milbemycin oxime has possible anthelmintic efficacy against Baylisascaris roundworms in captive kinkajous. We conclude that Baylisascaris infections are highly prevalent in wild-caught kinkajous in Japan and that most of the infected kinkajous were imported from the Republic of Guyana.

[Long-Term Survival of Gastric Cancer with Peritoneal Metastasis--A Case Report]

We report a case of almost 9-year survival of a patient with unresected gastric cancer with peritoneal metastasis. A 76-year-old Japanese man was admitted to the hospital for resection of gastric cancer, but it was not resected because of peritoneal metastasis. After discharge, the patient was treated with combination chemotherapy of S-1 and paclitaxel (PTX). After 8 cycles of chemotherapy, the tumor disappeared. We recommended surgical therapy, but he did not agree. The chemotherapy was continued for almost 9 years with 8 regimens including S-1 plus PTX (21+8+5 cycles), S-1 plus CPT-11 (11+2 cycles), S-1 plus docetaxel (DOC) (25 cycles), S-1 plus CDDP plus trastuzumab (1 cycle), PTX (5 cycles), PTX plus trastuzumab (1 cycle), DOC (6 cycles), and nab-PTX (1 cycle). With nutrition support provided through an enterocutaneous fistula and home parenteral nutrition, he has taken chemotherapy throughout without severe complications.

[A Case of Removable Self-Expandable Metallic Stent(SEMS)Placement for Gastric Tube Stenosis after Esophageal Cancer Resection]

A 68-year-old man underwent esophagectomy for early esophageal cancer. Postoperative upper gastrointestinal series and esophagogastroduodenoscopy showed gastric tube stenosis. To improve passage, a removable self-expandable metallic stent (SEMS) was placed across the stenotic lesion. Two weeks later, the stent was removed, and passage through the gastric tube improved. The patient has no symptoms of stenosis. A removable SEMS could be an option for the treatment of gastric tube stenosis after esophagectomy.

Positioning bedridden patients to reduce interface pressures over the sacrum and great trochanter

OBJECTIVE

In this study, we evaluated the effect of hip-joint rotation on the interface pressure over the sacrum and greater trochanter with a new protocol for positioning of bedridden elderly patients.

METHOD

The interface pressure values over the sacrum and greater trochanter in bedridden patients were evaluated. These were collected in the supine position, 90° lateral position, and 30° and 40° laterally inclined positions with external rotation or neutral positioning of the hip joint. Each interface pressure was assessed with a device measuring pressure distribution, after which, the peak pressure index (PPI) was calculated.

RESULTS

In the 17 patients examined, the PPI over the sacrum in the supine position was significantly greater than that in other positions. In the 30° and 40° laterally inclined positions, the PPIs over the greater trochanter were significantly lower in the neutral position of the hip joint compared with those in the external rotation position.

CONCLUSION

Our findings revealed the effects of hip-joint rotation on the interface pressure for the greater trochanter, possibly due to the increased distance between the greater trochanter and the sacrum caused by neutral position of the hip joint. The results demonstrate that it is to best place the hip joint in a neutral position when the legs are in contact with the bed in order to distribute the pressure over the greater trochanter in the 30° and 40° laterally inclined positions. These results can be applied to the clinical setting to improve patient positioning and decrease pressure ulcers.

DECLARATION OF INTEREST

The authors declare that they have no competing financial interests.

Fer tyrosine kinase oligomer mediates and amplifies Src-induced tumor progression

c-Src is upregulated in various human cancers, suggesting its role in malignant progression. However, the molecular circuits of c-Src oncogenic signaling remain elusive. Here we show that Fer tyrosine kinase oligomer mediates and amplifies Src-induced tumor progression. Previously, we showed that transformation of fibroblasts is promoted by the relocation of c-Src to non-raft membranes. In this study, we identified Fer and ezrin as non-raft c-Src targets. c-Src directly activated Fer by initiating its autophosphorylation, which was further amplified by Fer oligomerization. Fer interacted with active c-Src at focal adhesion membranes and activated Fer-phosphorylated ezrin to induce cell transformation. Fer was also crucial for cell transformation induced by v-Src or epidermal growth-factor receptor activation. Furthermore, Fer activation was required for tumorigenesis and invasiveness in some cancer cells in which c-Src is upregulated. We propose that the Src-Fer axis represents a new therapeutic target for treatment of a subset of human cancers.

[A case of partial hepatectomy and gastrectomy for hepatocellular carcinoma with direct invasion to the stomach]

An 81-year-old man treated with chronic hepatitis C virus (HCV)-related hepatitis and hepatocellular carcinoma (HCC) was diagnosed in 2010 with HCC recurrence (subclass S2) on computed tomography (CT). He refused surgery and was followed up without treatment. In 2012, he was admitted to our hospital because of hematemesis. Gastrointestinal endoscopy revealed a large tumor in the upper gastric corpus, and pathological examination of the tumor revealed HCC; hence, we diagnosed the patient with direct HCC invasion to the stomach. Although active bleeding from the tumor was controlled, he experienced repeated episodes of hematemesis, and the tumor increased in size. Therefore, partial hepatectomy and gastrectomy were performed. It was confirmed that the tumor invaded the stomach wall. Although surgery was effective for gastrointestinal bleeding caused by HCC invasion, the patient died 12 months after surgery because of multiple liver metastases and exacerbated liver failure.

Primary Sjögren's syndrome complicated by sarcoidosis and psoriasis vulgaris

Abstract Primary Sjögren's syndrome (SS), sarcoidosis (SA), and psoriasis vulgaris (PV) are all chronic diseases of unknown etiology. Recent studies suggest that activated T cells play a central role in their pathogenesis. We describe a case of a Japanese woman with primary SS complicated by SA and PV. To our knowledge, this is the first case in which these three diseases coexist. Although these three disorders may have a common immunopathogenic mechanism, the extreme rarity of their coexistence suggests that distinct etiological mechanisms are also involved and appear to play an important role in triggering and developing each disease.

[A case of partial pancreatectomy for recurrent metastatic renal cell carcinoma in the remnant pancreas after subtotal stomach-preserving pancreaticoduodenectomy]

We report a case in which recurrent pancreatic metastasis of renal cell carcinoma( RCC) in the remnant pancreas was resected 6 years after subtotal stomach-preserving pancreaticoduodenectomy (SSPPD). A 74-year-old man underwent right nephrectomy for RCC in 1991, left partial nephrectomy for left renal RCC metastasis in 1996, and SSPPD for pancreatic RCC metastasis in 2007. In November 2012, he was referred to our hospital with a tumor in the remnant pancreas, as seen on abdominal computed tomography (CT). Partial pancreatectomy for the recurrent metastatic RCC in the remnant pancreas was performed in January 2013. The tumor was histologically diagnosed as metastasis from clear cell RCC in the remnant pancreas. The postoperative course was uneventful, and the blood glucose level after surgery was well controlled using an oral hypoglycemic agent.

[Two cases of human epidermal growth factor receptor 2-positive advanced gastric cancer successfully treated with S-1, cisplatin, and trastuzumab combination therapy followed by curative resection]

We report 2 cases of human epidermal growth factor receptor 2 (HER2)-positive advanced gastric cancer successfully treated with a combination therapy of S-1, cisplatin( CDDP), and trastuzumab followed by curative resection. Case 1 involved a 62-year-old man with type 3 HER2-positive gastric cancer spanning the antrum of the stomach to the duodenal bulb and directly invading the pancreatic head( cT4b[ Panc] N3H0P0M0, Stage IIIC). We diagnosed it as an unresectable cancer, and selected S-1, CDDP, and trastuzumab for combination chemotherapy. S-1 (120 mg/body/day) was administered orally for 2 weeks, followed by 1 drug-free week as a course, and CDDP (60 mg/m2) and trastuzumab (8 mg/kg loading dose and 6 mg/kg maintenance) were administered by intravenous infusion on day 1. After the third course, significant tumor and lymph node reduction was observed; however, pyloric stenosis developed. Distal gastrectomy with D2 lymphadenectomy was performed. Case 2 involved a 62-year-old woman with type 4 HER2-positive gastric cancer from the angle of the stomach to the duodenal bulb and directly invading the pancreatic head (cT4b [Panc] N2H0P0M0, Stage IIIC). After the third course of combination therapy, significant tumor reduction and disappearance of lymph nodes metastasis was observed. We diagnosed the patient as having a resectable cancer, and performed distal gastrectomy with D2 lymphadenectomy.

Gap-junction-mediated Communication in Human Periodontal Ligament Cells

Periodontal tissue homeostasis depends on a complex cellular network that conveys cell-cell communication. Gap junctions (GJs), one of the intercellular communication systems, are found between adjacent human periodontal ligament (hPDL) cells; however, the functional GJ coupling between hPDL cells has not yet been elucidated. In this study, we investigated functional gap-junction-mediated intercellular communication in isolated primary hPDL cells. SEM images indicated that the cells were in contact with each other via dendritic processes, and also showed high anti-connexin43 (Cx43) immunoreactivity on these processes. Gap-junctional intercellular communication (GJIC) among hPDL cells was assessed by fluorescence recovery after a photobleaching (FRAP) analysis, which exhibited dye coupling between hPDL cells, and was remarkably down-regulated when the cells were treated with a GJ blocker. Additionally, we examined GJs under hypoxic stress. The fluorescence recovery and expression levels of Cx43 decreased time-dependently under the hypoxic condition. Exposure to GJ inhibitor or hypoxia increased RANKL expression, and decreased OPG expression. This study shows that GJIC is responsible for hPDL cells and that its activity is reduced under hypoxia. This is consistent with the possible role of hPDL cells in regulating the biochemical reactions in response to changes in the hypoxic environment.

A new calpain inhibitor protects left ventricular dysfunction induced by mild ischemia-reperfusion in in situ rat hearts

We have previously indicated that a new soluble calpain inhibitor, SNJ-1945 (SNJ), attenuates cardiac dysfunction after cardioplegia arrest-reperfusion by inhibiting the proteolysis of α-fodrin in in vitro study. Nevertheless, the in vivo study design is indispensable to explore realistic therapeutic approaches for clinical use. The aim of the present in situ study was to investigate whether SNJ attenuated left ventricular (LV) dysfunction (stunning) after mild ischemic-reperfusion (mI-R) in rat hearts. SNJ (60 μmol/l, 5 ml i.p.) was injected 30 min before gradual and partial coronary occlusion at proximal left anterior descending artery. To investigate LV function, we obtained curvilinear end-systolic pressure-volume relationship by increasing afterload 60 min after reperfusion. In the mI-R group, specific LV functional indices at midrange LV volume (mLVV), end-systolic pressure (ESP(mLVV)), and pressure-volume area (PVA(mLVV): a total mechanical energy per beat, linearly related to oxygen consumption) significantly decreased, but SNJ reversed these decreases to time control level. Furthermore, SNJ prevented the α-fodrin degradation and attenuated degradation of Ca(2+) handling proteins after mI-R. Our results indicate that improvements in LV function following mI-R injury are associated with inhibition of the proteolysis of α-fodrin in in situ rat hearts. In conclusion, SNJ should be a promising tool to protect the heart from the stunning.

[A case of sigmoid colon cancer with Virchow's lymph node metastasis successfully treated with chemotherapy]

We report the case of a 71-year-old woman suffering from advanced sigmoid colon cancer with Virchow's and para- aortic lymph node metastasis. Sigmoidectomy was performed for sigmoid colon cancer in January 2008, and pathological analysis revealed that it was Stage II(pT3, pN0, pM0, Cur A). The patient received capecitabine regimen as adjuvant chemotherapy from February 2008 to July 2008. However, in August 2008, a left cervical mass was detected associated with swelling, which was partially resected. Microscopic findings revealed lymph node metastasis from sigmoid colon cancer, and Virchow's and para-aortic lymph node metastasis were diagnosed. Therapy with FOLFOX and bevacizumab (Bmab) was started and continued for 8 cycles. Virchow's and para-aortic lymph node metastasis could no longer be detected in June 2009. FOLFOX+Bmab treatment was administered for 33 cycles and oxaliplatin was temporarily stopped due to adverse reactions, including neutropenia, peripheral neuropathy, and appetite loss. She had no recurrence for almost 3 years after stopping chemotherapy for Virchow's and para-aortic lymph node metastasis.

Optimum microcurrent stimulation intensity for galvanotaxis in human fibroblasts

OBJECTIVE

In this study, we develop methods to measure galvanotaxis of fibroblasts and determined the optimum conditions of electrical stimulation.

METHOD

An inverted 35mm dish containing cell suspensions (3×105 primary human skin fibroblasts, DMEM, and 10% FBS) was placed on the centre of a 100mm dish. The 35mm dish was removed 24 hours later, and culture medium was added to the 100mm dish. Fibroblasts were randomised (double-blind) into three groups, where electrical stimulation was given at varying intensities: 0UA (control), 50UA, and 100UA. Electrical stimulation (frequency=0.3Hz) was conducted, for a duration of 4 hours, with platinum electrodes in a CO2 incubator. We took pictures immediately before and 20 hours after stimulation. We calculated the migration ratio to the negative pole by dividing the area of attached fibroblasts after stimulation with that before stimulation.

RESULTS

The migration ratio to the negative pole was significantly higher in the 100UA group than in the control group (p<0.05). The ratios were 0.902±0.292 in the control group, 1.128±0.253 in the 50UA group, and 1.24±0.300 in the 100UA group.

CONCLUSION

This study observed the change in cell proliferation during the initial 24-hour period after plating and was thus able to quantitatively evaluate the migration. The results suggest that a low-intensity direct current promotes migration to the negative pole of human dermal fibroblasts, which is charged with positive electricity. Several clinical reports using the methods in this study showed the microcurrent efficacy for pressure ulcer healing. Electrical stimulation based on our in vitro experiment might be important for the development of physical therapy for pressure ulcers.

Structural and functional analyses of chicken liver ferritin

Characterization of ferritins from different species has provided insight into iron regulation mechanisms and evolutionary relationships. Here, we examined chicken liver ferritin, which comprises only H subunit and has 14.8 µg of Fe/100 µg of protein. The chicken H subunit apo homopolymer showed the same iron uptake rate as bovine H subunit homopolymer expressed with a baculovirus expression system (0.31 and 0.28 mmol of Fe/min per micromole of protein for chicken and bovine H subunit, respectively). Chicken H subunit apo homopolymer showed a significantly higher biotinylated hemin-binding activity than liver holoferritin. Although bovine spleen apoferritin, which has an L (liver or light):H (heart or heavy) subunit ratio of 1:1, also shows a significantly higher biotinylated hemin-binding activity than its holoferritin, these biotinylated hemin-binding activities were markedly lower than those of both chicken holo- and apoferritins. Binding of chicken holo- and apoferritin with biotinylated hemin was strongly inhibited by hemin but not iron-free hemin, protoporphyrin IX, or Zn-protoporphyrin. These findings demonstrate that chicken ferritin comprises only an H subunit, possesses ferroxidase activity as in mammalian ferritin H subunits, and binds heme more strongly than mammalian ferritins.

196 GLUTATHIONE S-TRANSFERASE THETA1 (GSTT1) IS DIFFERENTIALLY REGULATED FROM OTHER GLUTATHIONE S-TRANSFERASES IN GRANULOSA CELLS

Oxidative stress is a major source of aging that damages genomic and mitochondrial DNA, causing female reproductive disorders. Glutathione S-transferases (GST) are known to detoxify the metabolites of genotoxic molecules to more water-soluble and readily excretable forms. Therefore, most GST have been considered to be down-regulated by aging. We recently demonstrated that only GSTT1 is up-regulated in granulosa cells from aged, infertile patients and aged mice, although other kinds of GST are down-regulated in these cells (Ito et al. 2008 Fertil. Steril. 90, 1026–1035). Measurement of the GSTT1 level in granulosa cells binding to the patient’s oocytes could be used in the selection of oocytes of high quality, meaning that the GSTT1 level in granulosa cells could be a good indicator of age-related infertility. To do that, an understanding of the concrete relationship between aging and GSTT1 up-regulation is necessary. However, the regulation mechanism of GSTT1 in granulosa cells remains unclear. In the present study, we attempted to examine the difference in expression mechanisms between GSTT1 and other GST. First, the expression patterns of GSTT1 and GSTP (a major member of the GST) in aged granulosa cells from patients were observed by immunostaining. The GSTT1 was up-regulated (young: 25 to 34 years old, N = 9; aged: 38 to 43 years old, N = 12; P < 0.05) but the GSTP was down-regulated (young: 28 to 30 years, N = 5; aged: 38 to 42 years, N = 7; P < 0.05) in the aged group. Nuclear factor erythroid 2 p45-related factor 2 (Nrf2) is a transcription factor that regulates the expression of most GST, so in the next experiment, we examined the expression patterns of GSTT1 and GSTP in granulosa cells from Nrf2-disrupted (Nrf2–/–) mice by immunostaining. The GSTP was down-regulated in granulosa cells of Nrf2–/– mice compared with those of Nrf2+/– mice, although a significant difference was not observed in GSTT1. In addition, we confirmed these results by using mouse embryonic fibroblasts (MEF) from Nrf2–/– and Nrf2+/– mice, and the same results were obtained. Our previous experiment showed that GSTT1 was induced by FSH in human granulosa-like tumour cells (KGN cells). We analysed the expression level of other genes in FSH-stimulated KGN cells. The transcription levels of GSTP and Nrf2 were not induced by FSH. These results suggest that the expression of GSTT1 is not regulated by Nrf2 and is differentially regulated from other GST. The difference in regulation mechanisms between GSTT1 and other GST may result in the up-regulation of GSTT1 in the aging granulosa cells, and it may contribute to the constitution of the diagnosis of oocyte quality using the GSTT1 measurement.

Prevalence of herpes B virus genome in the trigeminal ganglia of seropositive cynomolgus macaques

Herpes B virus infection is almost asymptomatic in macaques (Macaca spp.), which are the natural hosts of this pathogen, but is the cause of high mortality in humans. Reactivation of the latent virus in the trigeminal ganglia (TG) results in the shedding of infectious particles into the oral mucosal membrane. Saliva contaminated with the reactivated virus from the ganglia of the natural host is considered to be important for viral transmission to humans and other monkeys. In the present study, we investigated the prevalence of the herpes B virus genome in the left and right TG of seropositive asymptomatic cynomolgus macaques. The latent virus genome was detected using a polymerase chain reaction and microplate hybridization assay. We found that the virus DNA was present in one or both TG of 12 of the 30 macaques (40%) tested, with the virus being detected from both TG in five of the 12 macaques and from a single TG in the remaining seven.

Optimization of a prominent oxygen-permeable device for pancreatic islets

BACKGROUND

We have demonstrated a culture bag system that is useful for pancreatic islet transplantation. To improve and simplify islet transplantation procedures from culture to transplantation, we developed a novel device specific for both islet culture and transplantation (TUBERO Device [TD]) using an oxygen-permeable material.

MATERIALS AND METHODS

Porcine islets with 30 minutes warm ischemia time were cultured for 24 hours at 37 degrees C in 5% CO2 and humidified air under three different procedures: (1) ordinary culture flask, (2) culture bag suitable for platelets, and (3) TD. Loss of islets during culture, glucose-stimulated insulin release as an islet functional test, and ADP/ATP ratio as an index of islet viability tests were evaluated to compare the devices. TD was further applied in two clinical islet transplantations using non-heart-beating donors in Japan.

RESULTS

The loss of islets during culture was considerably lower in the TD group. The stimulation index upon glucose challenge tests was significantly higher in the TD group than the others. The ADP/ATP ratio in TD group was significantly lower than that in the ordinary flask group, suggesting that the apoptotic islets were relatively lower among TD. Most importantly, TD was successfully applied both in the clinical islet cultures and in transplantation, resulting in excellent graft function.

CONCLUSIONS

We propose that the TD, a novel product, not only simplifies islet transplantation procedures, but also maintain the quality of isolated islets.