A BTB/POZ gene, NAC-1, a tumor recurrence-associated gene, as a potential target for Taxol resistance in ovarian cancer

PURPOSE

We previously determined that NAC-1, a transcription factor and member of the BTB/POZ gene family, is associated with recurrent ovarian carcinomas. In the current study, we investigated further the relationship between NAC-1 expression and ovarian cancer.

EXPERIMENTAL DESIGN

NAC-1 expression was assessed by immunohistochemistry, and clinical variables were collected by retrospective chart review. SiRNA system and NAC-1 gene transfection were used to asses NAC-1 function in Taxol resistance in vivo.

RESULTS

Overexpression of NAC-1 correlated with shorter relapse-free survival in patients with advanced stage (stage III/IV) ovarian carcinoma treated with platinum and taxane chemotherapy. Furthermore, overexpression of NAC-1 in primary tumors predicted recurrence within 6 months after primary cytoreductive surgery followed by standard platinum and taxane chemotherapy. NAC-1 expression levels were measured and compared among the human ovarian cancer cell line (KF28), cisplatin-resistant cell line (KFr13) induced from KF28, and paclitaxel-resistant cell lines (KF28TX and KFr13TX) induced by exposing KF28 and KFr13 to dose-escalating paclitaxel. Overexpression of NAC-1 was observed in only the Taxol-resistant KF28TX and KFr13 TX cells but not in KF28 or cisplatin-resistant KFr13 cells. To confirm that NAC-1 expression was related to Taxol resistance, we used two independent but complementary approaches. NAC-1 gene knockdown in both KF28TX and KFr13TX rescued paclitaxel sensitivity. Additionally, engineered expression of NAC-1 in RK3E cells induced paclitaxel resistance.

CONCLUSIONS

These results suggest that NAC-1 regulates Taxol resistance in ovarian cancer and may provide an effective target for chemotherapeutic intervention in Taxol-resistant tumors.

Analysis of 11C-methionine uptake in low-grade gliomas and correlation with proliferative activity

BACKGROUND AND PURPOSE

The relationship of (11)C-methionine (MET) uptake and tumor activity in low-grade gliomas (those meeting the criteria for World Health Organization [WHO] grade II gliomas) remains uncertain. The aim of this study was to compare MET uptake in low-grade gliomas and to analyze whether MET positron-emission tomography (PET) can estimate tumor viability and provide evidence of malignant transformation.

MATERIALS AND METHODS

We studied glioma metabolic activity in 49 consecutive patients with newly diagnosed grade II gliomas by using MET PET before surgical resection. On MET PET, we measured tumor/normal brain uptake ratio (T/N ratio) in 21 diffuse astrocytomas (DAs), 12 oligodendrogliomas (ODs), and 16 oligoastrocytomas (OAs). We compared MET T/N ratio among these 3 tumors and investigated possible correlation with proliferative activity, as measured by Mib-1 labeling index (LI).

RESULTS

MET T/N ratios of DA, OD, and OA were 2.11 +/- 0.87, 3.75 +/- 1.43, and 2.76 +/- 1.27, respectively. The MET T/N ratio of OD was significantly higher than that of DA (P < .005). In comparison of MET T/N ratios with the Mib-1 LI, a significant correlation was shown in DA (r = 0.63; P < .005) but not in OD and OA.

CONCLUSION

MET uptake in DAs may be closely associated with tumor viability, which depends on increased amino acid transport by an activated carrier-mediated system. DAs with lower MET uptake were considered more quiescent lesions, whereas DA with higher MET uptake may act more aggressively.

Expression of the bric-a-brac tramtrack broad complex protein NAC-1 in cervical carcinomas seems to correlate with poorer prognosis

PURPOSE

Recent studies have suggested a novel oncogenic role of a bric-a-brac tramtrack broad complex (also known as POZ) domain gene, NAC-1, in ovarian carcinomas. The aim of this study was to clarify the functional role of NAC-1 in human cervical carcinomas.

EXPERIMENTAL DESIGN

NAC-1 expression in cervical cancer was assessed by immunohistochemistry, and data on clinical variables were collected by retrospective chart review. NAC-1 gene knockdown using small interfering RNA and a NAC-1 gene transfection system were used to asses NAC-1 function in cervical cancer in vivo.

RESULTS

Immunohistochemical and gene expression analysis revealed that NAC-1 is significantly overexpressed in cervical adenocarcinomas and adenosquamous carcinomas compared with squamous cell carcinomas. Patients with squamous cell carcinomas positive for NAC-1 expression who received radiotherapy had significantly shorter overall survival than peers whose tumors did not express NAC-1, and multivariate analysis showed that NAC-1 expression was an independent prognostic factor for overall survival after radiotherapy. Overexpressions of the NAC-1 gene stimulated cell proliferation in cervical carcinoma cells of the TCS, CaSki, and HeLa P3 lines, which do not have endogenous NAC-1 expression. NAC-1 gene knockdown inhibited cell growth and induced apoptosis in HeLa, HeLa TG, and ME180 cells, all of which overexpressed NAC-1.

CONCLUSIONS

Our findings suggest that NAC-1 may play an important role in cervical carcinomas; moreover, these findings provide a rationale for future development of NAC-1-based therapy for cervical carcinomas that overexpress this candidate oncogene.

[Two cases of endometrial stromal sarcoma (ESS) in which survival was prolonged by administration of MPA]

Endometrial stromal sarcoma (ESS) is very rare. It accounts for 0.5% of all uterine corpus malignant tumors and 10% of all malignant non-epithelial tumors. MPA is one effective hormonal treatment for ESS. We describe two cases in which patients with metastatic low-grade ESS lesions had prolonged survival with MPA therapy. Case 1 was a 50-year-old woman with a low-grade uterine endometrial stromal tumor who had been operated on at another hospital. She had been followed for three years. She had pelvis metastases with infiltration into the bladder, and pulmonary metastases. She had an incomplete response to chemotherapy. We initiated MPA therapy, which resulted in significant improvement in her metastatic lesions. Case 2 was a 58-year-old woman with stage Ic low-grade ESS who presented with abnormal uterine bleeding. Following surgery (TAH+BSO), MPA therapy was initiated and she had no recurrence. After 1 year and 7 months, she discontinued the MPA because it worsened her articular rheumatism. Her cancer recurred with pelvic and paraaortic lymph node metastasis. She was treated with chemotherapy, MPA and radiotherapy. Her metastases improved, and the patient has continued to survive on MPA therapy alone. These cases suggest that MPA might be an effective hormonal therapy for patients with low-grade ESS.

Metabolic assessment of gliomas using 11C-methionine, [18F] fluorodeoxyglucose, and 11C-choline positron-emission tomography

BACKGROUND AND PURPOSE

Positron-emission tomography (PET) is a useful tool in oncology. The aim of this study was to assess the metabolic activity of gliomas using (11)C-methionine (MET), [(18)F] fluorodeoxyglucose (FDG), and (11)C-choline (CHO) PET and to explore the correlation between the metabolic activity and histopathologic features.

MATERIALS AND METHODS

PET examinations were performed for 95 primary gliomas (37 grade II, 37 grade III, and 21 grade IV). We measured the tumor/normal brain uptake ratio (T/N ratio) on each PET and investigated the correlations among the tracer uptake, tumor grade, tumor type, and tumor proliferation activity. In addition, we compared the ease of visual evaluation for tumor detection.

RESULTS

All 3 of the tracers showed positive correlations with astrocytic tumor (AT) grades (II/IV and III/IV). The MET T/N ratio of oligodendroglial tumors (OTs) was significantly higher than that of ATs of the same grade. The CHO T/N ratio showed a significant positive correlation with histopathologic grade in OTs. Tumor grade and type influenced MET uptake only. MET T/N ratios of more than 2.0 were seen in 87% of all of the gliomas. All of the tracers showed significantly positive correlations with Mib-1 labeling index in ATs but not in OTs and oligoastrocytic tumors.

CONCLUSION

MET PET appears to be useful in evaluating grade, type, and proliferative activity of ATs. CHO PET may be useful in evaluating the potential malignancy of OTs. In terms of visual evaluation of tumor localization, MET PET is superior to FDG and CHO PET in all of the gliomas, due to its straightforward detection of "hot lesions".

Genetic classification of ovarian carcinoma based on microsatellite analysis: relationship to clinicopathological features and patient survival

Ovarian carcinomas can progress through two pathways of genomic instability: chromosomal instability (CIN) and microsatellite instability (MSI). However, it is unknown whether these two mechanisms could be distinguished from each other in the molecular characteristics in ovarian carcinomas. We hypothesized that these two pathways are not always independent in ovarian carcinomas. We classified 51 ovarian carcinomas based on their MSI and CIN status using microsatellite analysis and assessed whether these carcinogenic pathways affect the clinicopathological features and patient survival. Of the 51 cases, 77.4% of the tumors were microsatellite stable (MSS), 5.9% were MSI-Low (MSI-L) whilst, 16.7% were MSI-High (MSI-H). Overall, 56.8% of the tumors had at least one loss of heterozygosity (LOH) event, i.e., 56.8% CIN. Notably, we identified a significant degree of overlap between the MSI and CIN pathways. Of the 34 tumors with LOH events (CIN), 5 (14.7%) were MSI-H. In addition, of the 7 tumors that were MSI-H, 5 (71.4%) had one or more LOH events (CIN). We also identified a group of 29.4% of all tumors that did not demonstrate any evidence of either of the two pathways of genomic instability as they were MSS/MSI-L with no evidence of LOH events (CIN negative). Furthermore, patients with CIN with MSS/MSI-L have a significantly shorter overall survival compared to those in other genetic categories (P=0.019). Cox regression analysis revealed that tumors with CIN with MSS/MSI-L exhibit a poor prognostic outcome after adjustment for FIGO stage and grade. These findings suggest that some ovarian carcinomas have a significant degree of overlap between the two pathways of genomic instability and that the genetic classification using microsatellite markers may represent a potential new biomarker of risk prediction in ovarian carcinoma.

Therapy-related myelodysplasia and acute myeloid leukemia following paclitaxel- and carboplatin-based chemotherapy in an ovarian cancer patient: a case report and literature review

Alkylating agents have strong leukemogenic potential. There are a number of recent acute myeloid leukemia (t-AML) cases related to previous paclitaxel exposure. These leukemias tend to be of aggressive subtypes with long-latency periods. Unlike previously reported cases, the present case was of the secondary acute megakaryoblastic myeloid leukemia (AML M7) subtype. Additionally, it did not harbor a translocation in chromosome 19. A 73-year-old woman was diagnosed with t-AML M7 with antecedent myelodysplasia. Leukemia followed a second induction of paclitaxel- and carboplatin-based chemotherapy for recurrent ovarian cancer. Her second induction began 25 months after completion of her first course of chemotherapy. The increased incidence of postpaclitaxel leukemia suggests a probable role for paclitaxel as a leukemogenic agent. It highlights the importance of assessing for leukemia risk factors prior to beginning paclitaxel therapy.

305 TRANSGENIC CLONED PIGS EXPRESSING ORANGE FLUORESCENT PROTEIN KUSABIRA-ORANGE

Transgenic (Tg)-cloned pigs expressing fluorescent proteins are very useful in research such as cell or tissue transplantation studies. In this study, we produced Tg-cloned pigs with an orange fluorescent protein, humanized Kusabira-Orange (huKO), and analyzed the characteristics of these pigs. Fetal fibroblast cells transduced with huKO gene by a gene silencing-resistant retroviral vector, pDΔNhuKO (Suzuki et al. 2002 J. Neurochem. 82, 953–960) were used as nuclear donors. Recipient cytoplasts were prepared using oocytes matured in vitro in NCSU23. The nuclear transfer (NT) embryos were transferred into oviducts of estrus-synchronized recipient gilts after culture in PZM-5 for 1 or 2 days. Cloned pigs obtained were analyzed by Southern blotting for the transgene integration. A total of 23 organs and tissues, including brain, eye, internal and reproductive organs, skin, skeletal muscle, and cartilage were examined by fluorescence stereomicroscopy. Cryo- and paraffin-embedded tissue sections were also prepared to examine fluorescence expression. Immunofluorescent staining of brain cryosection and flow cytometry analysis of peripheral blood cells were performed to identify huKO-expressing cells. Transfer of 429 NT embryos into 4 recipients resulted in 18 (4.2%) cloned offspring. Southern blotting analysis of the cloned pigs confirmed transduction of 2 to 17 copies of the huKO gene in each pig. Autopsy was performed in 6 pigs, and orange fluorescence was confirmed in all the tissues and organs examined in each pig. In addition, prominent orange fluorescence was detected in pancreatic islets and renal glomeruli, indicating that these transgenic pigs are ideal for islet cell transplantation studies. Expression of huKO was also detected in neurons, microglia, and astrocytes in the brain, and granulocytes, monocytes, macrophages, lymphocytes, and platelets in the peripheral blood cells, whereas the expression level in red blood cells was lower. Re-cloning was performed using primary culture fibroblast cells established from 2 Tg-cloned pigs. Transfer of 300 re-cloned embryos into 4 recipients resulted in 3 pregnancies. A re-cloned fetus at Day 44 of gestation showed systemic fluorescence. These results demonstrate that the retroviral vector pD?NhuKO is resistant to gene silencing in pigs, that transduction and expression of the huKO gene had no lethal effects on fetal development, and that a Tg-cloned pig expressing orange fluorescence can be produced by NT of fetal fibroblast cells transduced with the huKO gene. This study was supported by PROBRAIN.

85 VITRIFICATION OF IN VITRO-MATURED PORCINE OOCYTES AT THE METAPHASE-II STAGE

Cryopreservation of mammalian metaphase-II (M-II) oocytes is still impractical compared to that of early stage embryos. In this study we examined the effects of delipation and mitotic spindle stabilization in order to improve the post-vitrification survival rate of in vitro-matured (IVM) porcine oocytes at the M-II stage. Cumulus–oocyte complexes that had been collected from slaughterhouse ovaries were matured in vitro in NCSU23 supplemented with 0.6 mm cysteine, 10 ng mL–1 epidermal growth factor (EGF), 10% porcine follcular fluid (PFF), and 10 IU mL–1 eCG and hCG. The denuded M-II oocytes were vitrified in the presence of 30% ethylene glycol and 0.5 m sucrose using the minimum volume cooling (MVC) method with a MVC plate (Cryotop�; Kitazato Supply, Tokyo, Japan). Vitrified embryos were rewarmed by immersing the MVC plate directly into rewarming solution containing 1 m sucrose and 20% calf serum at 39�C for 1 min, followed by stepwise dilution of the cryoprotectants. We compared the effects of previtrification treatments, namely, (1) delipation, (2) mitotic spindle stabilization, (3) delipation + mitotic spindle stabilization, and (4) no treatment. For delipation, we used a noninvasive method (Esaki et al. 2004 Biol. Reprod. 71, 432–437) that we had published previously with slight modification. The embryos were treated with 4% trypsin at 38�C for approximately two min to expand the zona pellucida, and then centrifuged (12 000g, 38�C 23 min) with 7.5 µg mL–1 cytochalasin B to polarize cytoplasmic lipid droplets within the perivitelline space. For mitotic spindle stabilization, M-II oocytes were vitrified in the presence of 1 µm paclitaxel. After the oocytes were rewarmed, electrical activation of the oocytes (150 V mm–1, 100 µs, one time) was carried out to induce parthenogenesis. These parthenogenetic embryos were cultured in PZM-5 for 7 days, and the number of vitrified embryos that developed into blastocysts with respect to each treatment was determined. The blastcyst formation rate and mean cell numbers of the blastcysts were compared among the treatment groups (chi-square test, Tukey's test). Of the 50 M-II oocytes that had been vitrified without pretreatment, only one oocyte (2.0%) developed into a blastocyst with 20 cells. By contrast, the number of vitrified embryos that developed into blastocysts was significantly high when they were delipated prior to vitrification (37.8%, 14/37, 64.0 � 9.6; P < 0.01). Mitotic spindle stabilization also improved the survival rate of vitrified oocytes (18.6%, 21/113, 56.7 � 9.6; P < 0.01). The combination of delipation and mitotic spindle stabilization produced the highest number of vitrified oocytes that developed into blastocysts (43.8%, 35/80, 69.4 � 6.4), although the difference between the combination group and the delipation group was not significant. These results indicate that blastocysts can be produced very efficiently from IVM porcine oocytes that have been vitrified at the M-II stage using both noninvasive delipation and mitotic spindle stabilization procedures.

84 PRODUCTION OF CLONED PIGLETS FROM NUCLEAR TRANSFER EMBRYOS AFTER VITRIFICATION

Cryopreservation of cloned embryos is expected to be beneficial in improving the efficiency of somatic cell cloning in pigs. We have already demonstrated that normal piglets can be produced from in vitro-matured and fertilized (IVM/IVF) embryos vitrified at an early cleavage stage after delipation (Nagashima et al. 2007 Biol. Reprod. 76, 900–905). In this study we utilized this technique in an attempt to produce piglets from cloned embryos reconstructed with IVM oocytes. Nuclear transfer (NT) embryos were reconstructed using oocytes matured in vitro in NCSU23 and preadipocytes as nuclear donors. The embryos were cultured in PZM-5 for approximately 98 h, and those that had developed to the morula stage were delipated using a noninvasive method described previously (Esaki et al. 2004 Biol. Reprod. 71, 432–437). The embryos were treated with 4% trypsin at 38�C for 1 to 4 min to induce a slight swelling of the zona pellucida, and then centrifuged (12 000g, 38�C, 23 min) with 7.5 µg mL–1 cytochalasin B to polarize cytoplasmic lipid droplets within the perivitelline space. The embryos were cultured for 1 h and vitrified by the minimum volume cooling (MVC) method using a MVC plate (Cryotop�; Kitasato Supply Co., Tokyo, Japan) in the presence of 15% ethylene glycol, 15% DMSO, and 0.5 m sucrose as cryoprotectants. Vitrified embryos were rewarmed by immersing the MVC plate diretly into rewarming solution containing 1 m sucrose and 20% calf serum at 38�C for 1 min, followed by stepwise dilution of the cryoprotectants. The rewarmed embryos were cultured for 2 days to the blastocyst stage, and then treated with 0.5% pronase to remove the zona pellucida before transfer to the uterine horn of recipients. A total of 103 vitrified blastocysts were transferred to 2 recipient gilts. Both gilts became pregnant and farrowed 2 and 4 piglets, respectively (6/103, 5.8%). These results demonstrate that cloned piglets can be produced from NT embryos that have been cryopreserved at the morula stage using noninvasive delipation and vitrification procedures. This study was supported by PROBRAIN.

A case of extremely chemoresistant pure pleomorphic rhabdomyosarcoma of the uterus associated with a high serum LDH level

BACKGROUND

Pleomorphic rhabdomyosarcoma (RMS) of gynecologic origin is an exceedingly rare, highly malignant tumor. Only a few cases have been reported in the last decades.

CASE REPORT

A 60-year-old postmenopausal woman presented with a high LDH level of unknown origin. Ultimately, she was diagnosed with pleomorphic RMS. She underwent total hysterectomy, bilateral salpingo-oophorectomy, left pelvic and paraaortic lymphadenectomy and partial omentectomy. Surgery was followed by systemic chemotherapy and pelvic irradiation. Unfortunately, the patient did not respond to treatment. Her disease course correlated with the fluctuation of plasma LDH levels. Ultimately she died within 20 months of the diagnosis.

CONCLUSION

It is important to have better insight and to set a standard multimodal treatment for adult RMS. In addition, plasma LDH levels can be considered as a prognostic marker for RMS, particularly in advanced stage.

NAC-1 controls cell growth and survival by repressing transcription of Gadd45GIP1, a candidate tumor suppressor

Cancer mortality and morbidity are primarily related to recurrent tumors, and characterization of recurrence-associated genes should illuminate fundamental properties of tumor progression and provide new therapeutic targets. We have previously identified NAC-1, a member of the BTB/POZ gene family and a transcription repressor, as a gene associated with recurrent ovarian carcinomas after chemotherapy. We further showed that homodimerization of NAC-1 proteins is essential for tumor growth and survival. In this study, we applied serial analysis of gene expression and identified growth arrest and DNA-damage-inducible 45-gamma interacting protein (Gadd45GIP1) as one of the downstream genes negatively regulated by NAC-1. NAC-1 knockdown in both SKOV3 and HeLa cells that expressed abundant endogenous NAC-1 induced Gadd45GIP1 expression transcriptionally; on the other hand, engineered expression of NAC-1 in NAC-1-negative RK3E and HEK293 cells suppressed endogenous Gadd45GIP1 expression. In NAC-1-expressing tumor cells, induction of dominant negative NAC-1 conferred a growth-inhibitory effect that can be partially reversed by Gadd45GIP1 knockdown. Induced Gadd45GIP1 expression resulted in growth arrest in SKOV3 and HeLa cells both in vitro and in vivo. In summary, NAC-1 contributes to tumor growth and survival by at least inhibiting Gadd45GIP1 expression, which has a tumor suppressor effect in cancer cells.

Correlation between the expression abnormalities of E-cadherin-β-catenin complex and lymph node metastasis (LNM) in early gastric cancer

15105

Background: Therapy for early gastric cancer (GC) varies according to risk of LNM. When the possibility of LNM is very remote, the primary lesion can be resected by the minimally invasive endoscopic surgery only. Therefore, useful parameters predicting LNM are needed. E-cadherin, a component of the cell-cell junctional structure, is known to correlate with GC. In vitro, previous studies elucidated that disorders of cell-cell junction increased the potential of metastasis, and that phosphorylation of β-catenin by c-erbB-2 induced loss of membranous E-cadherin and β-catenin, resulting in junctional structure disorders. Here we evaluated significance of analysis of these molecules in LNM prediction in early GC. Methods: The clinicopathological features and immunohistochemical expressions of E-cadherin, β-catenin, and c-erbB-2 in the primary lesion were studied in 28 patients (LNM +ve group: 14, LNM1 -ve group: 14) selected from 272 patients who underwent radical surgery for early GC between April 2000 to March 2004 at our hospital. All the patients consented to use of their stomach tissues for the clinical study afterwards. Statistical analysis was performed by t-test or χ2 test. Results: The clinicopathological features showed no significant differences between both groups. Loss of the membranous E-cadherin was noticed in 12 (85%) of the 14 LNM +ve patients, and in 8 (57%) of the 14 LNM -ve patients (p=0.209). This result was more remarkable in the intestinal type GC as the corresponding figures were 83% (5 of 6 ) and 16% (1 of 6) (p=0.083), respectively. Loss of the membranous β-catenin also showed a remarkable similar trend in the intestinal type GC, and the corresponding figures were 100% (6 of 6) and 50% (3 of 6) (p=0.182), respectively. Two patients showed over-expression of c-erbB2 and nuclear accumulation of β-catenin, and both had intestinal type GC with LNM. Conclusions: These results suggested that the same molecular signal pathway - as in vitro - including E-cadherin, β-catenin, and c-erbB2 induced LNM in early GC (intestinal type). We concluded that analysis of the expressions of these molecules is useful for not only LNM prediction but also determination of the therapeutic modality especially in intestinal type early GC.

No significant financial relationships to disclose.

Amplicon profiles in ovarian serous carcinomas

Ovarian serous carcinoma is the most common and lethal type of ovarian cancer and its molecular etiology remains poorly understood. As an ongoing effort to elucidate the pathogenesis of ovarian serous carcinomas, we assessed the DNA copy number changes in 33 high-grade serous carcinomas and 10 low-grade serous tumors by using a genome-wide technique, single nucleotide polymorphism array, performed on affinity-purified tumor cells from fresh surgical specimens. Compared to low-grade tumors, high-grade serous carcinomas showed widespread DNA copy number changes. The most frequent alterations were in loci harboring candidate oncogenes: cyclin E1 (CCNE1), AKT2, Notch3 and PIK3CA as well as in novel loci, including 12p13, 8q24, 12p13 and 12q15. Seven amplicons were selected for dual color fluorescence in situ hybridization analysis in approximately 90 high-grade serous carcinomas and 26 low-grade serous tumors, and a high level of DNA copy number gain (amplification) was found in CCNE1, Notch3, HBXAP/Rsf-1, AKT2, PIK3CA and chr12p13 occurring in 36.1%, 7.8%, 15.7%, 13.6%, 10.8% and 7.3% of high-grade serous carcinomas. In contrast, we did not observe high level of ERBB2 amplification in any of the samples. Low-grade tumors did not show DNA copy number gain in any of the loci, except in 2 (8%) of 24 low-grade tumors showing low copy number gain in the Notch3 locus. Taken together, our results provide the first comprehensive analysis of DNA copy number changes in highly pure ovarian serous carcinoma. These findings may have important biological and clinical implications.

Focal brain glucose hypometabolism in patients with neuropsychologic deficits after diffuse axonal injury

BACKGROUND AND PURPOSE

Neuropsychologic deficits are well-known sequelae of traumatic brain injury. However, the cerebral correlates of these deficits are still unclear. The aim of the present study was to elucidate the regions of cerebral dysfunction correlated with such neuropsychologic deficits after traumatic brain injury.

METHODS

Sets of fluorine-18 fluorodeoxyglucose-positron-emission tomography (FDG-PET) images in the resting state were obtained from 12 patients with neuropsychologic deficits after diffuse axonal injury and from 32 healthy volunteers. The cortical metabolic activity of each subject's PET image sets was extracted using 3D stereotactic surface projection (3D-SSP). A "normal" data base was created using the extracted datasets of the healthy subjects. The patients' datasets were compared with the normal data base by calculating a statistical Z-score on a pixel-by-pixel basis in searches for focal metabolic abnormalities.

RESULTS

Group comparisons revealed hypometabolism in the cingulate gyrus with additional involvement of the lingual gyrus and cuneus. Individual case-by-case analyses disclosed differences in the site and extent of the hypometabolism in the cingulate gyrus of each case. Predominant hypometabolism was found in the anterior cingulate gyrus of 6 patients, the middle cingulate gyrus of 2 patients, and the posterior cingulate gyrus of 4 patients.

CONCLUSION

Interpretation of FDG-PET using 3D-SSP facilitates the identification of regional hypometabolism in the cerebral cortex of patients after diffuse axonal injury. Dysfunction of the cingulate gyrus, lingual gyrus, and cuneus may play a crucial role in neuropsychologic deficits after traumatic brain injury.

126 CRYOPRESERVATION OF PORCINE EMBRYOS DERIVED FROM IVM OOCYTES

We have reported that a combination of delipation (removal of cytoplasmic lipid droplets from blastomeres) and vitrification by means of the minimum-volume cooling (MVC) method successfully cryopreserves porcine in vitro-matured/fertilized (IVM/IVF) embryos, and that normal piglets are produced from these embryos (Hiruma et al. 2006 Reprod. Fertil. Dev. 18, 157). We have also reported that IVM-derived embryos that undergo noninvasive delipation (i.e. micromanipulation is not required) and vitrification develop into blastocysts at a high rate (Esaki et al. 2004 Biol. Reprod. 71, 432–437). In this study, we examined whether fetuses can be produced from the IVM-derived embryos that have been delipated noninvasively and vitrified. Cumulus–oocyte complexes that had been collected from slaughterhouse ovaries were in vitro-matured in NCSU23 medium. The IVM oocytes were activated to produce parthenogenetic embryos. We used the embryos at the 4- to 8-cell (67 h after activation) and morula (98 h) stages in the following experiments. Embryos were treated with 4% trypsin (in PBS) at 38�C for 1 to 4 min to expand the zona pellucida. Next, the embryos were centrifuged (12 000g, 38�C, 23 min) in TL-HEPES-PVP containing 7.5 �g mL-1 cytochalasin B to polarize cytoplasmic lipid droplets within the perivitelline space. These embryos were cultured for 1 to 3 h and then vitrified. The post-thaw viability of the embryos was assessed based on their ability to develop into blastocysts and fetuses (21 to 23 days old). The embryos were vitrified using the MVC method with 15% ethylene glycol, 15% DMSO, and 0.5 M sucrose as cryoprotective agents. PZM-5 was used for culturing the embryos. In embryo transfer experiments, after thawing, the embryos were cultured for 36 or 72 h until they developed into morulae or 4- to 8-cell blastocysts, respectively; they were then treated with 0.5% pronase to remove the zona pellucida, and transferred to the uterine horns of estrus-synchronized recipients 6 days after onset of estrus. The proportion of vitrified embryos that developed into blastocysts and the mean cell number of the blastocysts were similar to those of non-vitrified control embryos, irrespective of the embryonic stage (4- to 8-cell stage: 42.1%, 22/51, 63.0 � 7.8 vs. 64.7%, 22/34, 74.2 � 7.1, respectively; morula stage: 77.6%, 38/49, 69.6 � 7.2 vs. 83.3%, 45/54, 66.2 � 5.9, respectively). Seventeen embryos that had been vitrified at the 4- to 8-cell stage gave rise to 3 fetuses after transfer into one recipient (17.6%). Fifty-three embryos that had been vitrified at the morula stage were transferred into 3 recipients. All recipients became pregnant and produced a total of 17 fetuses (32.1%). These results suggest that porcine IVM-derived embryos that have been cryopreserved by the combination of noninvasive delipation and vitrification by the MVC method are highly viable.

408 FOREIGN GENE INTEGRATION PATTERNS IN TRANSGENIC PORCINE FETUSES PRODUCED BY ICSI-MEDIATED GENE TRANSFER

We previously reported that transgenic (TG) pigs can be produced from in vitro-matured oocytes using intracytoplasmic sperm injection-mediated gene transfer (ICSI-mediated method) (Kurome et al. 2006 Transgenic Res. 15, 229–240). We subsequently studied the expression of a foreign gene which had been introduced by the ICSI-mediated method. We found that the ICSI-mediated method is considerably less likely than the pronuclear microinjection method to produce embryos in which transgene-positive and transgene-negative cells co-exist, that is, mosaic embryos (Saito et al. 2006 Reprod. Fertil. Dev. 18, 297 abst). Therefore, in order to further investigate the ICSI-mediated method, the present study was conducted to address the integration patterns of foreign genes introduced by this method. In particular, we wished to determine the number of transgene copies and number of chromosomal integration sites. TG pig fetuses, obtained by the ICSI-mediated method in a separate cardiac disease model study, were used in the present study. Porcine cumulus-oocyte complexes that had been collected from slaughterhouse ovaries were subjected to in vitro maturation in NCSU23 medium to produce MII oocytes to be used in this study. Porcine spermatozoa frozen in Beltsville Thawing Solution (BTS) were thawed rapidly in a 37�C water bath, and each spermatozoon was decapitated using ultrasound (28 kHz, 100 W; W-113; Honda Electronics Co., Ltd, Aichi, Japan). The heads (2 to 5 � 105/10 �L) were co-incubated with 2.5 ng �L-1 of rabbit calreticulin cDNA (�MHC-CRT-HA: 7.5 kb) for five min at room temperature, and then microinjected into MII oocytes using a piezo-micromanipulator. An electric stimulus (DC 150 V mm-1, 100 �s) was applied 10 to 40 min after microinjection in order to activate the oocytes. The embryos were cultured in PZM-5 medium for one to two days, and then transferred into the oviducts of recipient gilts, whose estrous cycle had been synchronized using 1000 IU eCG and 1500 IU hCG. Fetuses were collected 33 or 50 days later, and a primary cell line (fibroblast) was established. For each fetus, the number of transgene copies was determined by Southern blot. In addition, the chromosomal sites, where the foreign gene had integrated, were identified, and the number of integration sites was determined by fluoresent in situ hybridization (FISH). A total of 454 ICSI embryos were transferred to 4 recipients (92 to 135 embryos/recipient). All recipients became pregnant and 23 fetuses (5.1%, 23/454), including 7 TG fetuses (30.4%, 7/23), were obtained. Southern blot analysis showed that the number of transgene copies varied between 1 and 300 (1 copy: 1 fetus; 10 copies: 2 fetuses; 30 copies: 3 fetuses; 300 copies: 1 fetus). FISH analysis showed that in TG fetuses, the foreign gene had integrated at only a single chromosomal site, and this site varied from TG fetus to TG fetus. These results demonstrate that, in the case of ICSI-mediated gene transfer, as is the case for gene transfer by pronuclear microinjection, the integration patterns are: multiple copy, random site, and single site integration. This study was supported by PROBRAIN.

64 PRODUCTION OF TRANSGENIC CLONED PIGS BY MEANS OF SOMATIC CELL NUCLEAR TRANSFER USING KUSABIRA-ORANGE GENE-TRANSFECTED CELLS

Cloned pigs that express cell markers such as fluorescent proteins (Vintersten et al. 2004 Genesis 40, 241–246) are useful in biomedical research in areas such as cell/tissue transplantation and regenerative medicine. In this study, we attempted to produce transgenic cloned pigs from porcine fetal fibroblasts which carry the gene of red fluorescent protein, humanized Kusabira-Orange (huKO). We examined whether huKO-transfected cells are suitable as nuclear donors for somatic cell cloning, and whether red fluorescence can be detected in the cloned embryos. We used porcine fetal fibroblasts transfected with the huKO gene and a retroviral vector as the nuclear donor cells. Non-transfected cells were used as the control. Cumulus–oocyte complexes collected from slaughterhouse ovaries were in vitro-matured in NCSU23 medium to produce recipient oocytes. Nuclear transfer was conducted using a previously reported method (Kurome et al. 2003 Cloning Stem Cells 5, 367–377); the following parameters which determine the overall efficiency of nuclear transfer were investigated: (1) fusion rate between the donor cells and recipient oocytes, (2) rates of normal cleavage and blastocyst formation of the NT embryos, and (3) cell numbers in each blastocyst. A DC pulse (190 V mm-1) was used for electric fusion, and NCSU23 or PZM-5 medium was used for culturing the cloned embryos. The NT embryos on Day 7 were examined under a fluorescence microscope (G excitation) in order to evaluate the expression of red fluorescence. Some cloned embryos at the 1- to 8-cell stage (Day 1 or 2) were transferred into oviducts of estrus-synchronized recipient gilts. There was no significant difference (chi-square test) between the huKO and the control groups in the rate of fusion (132/151, 87.4% vs. 134/147, 91.2%, respectively) and cleavage rate (78/132, 59.1% vs. 86/134, 64.2%, respectively). A significantly greater percentage of huKO cell-derived embryos developed into blastocysts than did control cell-derived embryos (37/132, 28.0% vs. 20/134, 14.9%, respectively; P &lt; 0.05). However, there was no significant difference in the blastocyst cell numbers (Student&apos;s t-test: 48.6 &plusmn; 4.8 vs. 42.3 &plusmn; 4.9, respectively). Of the 132 NT embryos, 116 (87.9&percnt;) expressed red fluorescence. The percentage of blastocysts expressing red fluorescence was 94.6&percnt; (35/37). These results demonstrate that it is possible to obtain cloned blastocysts at a high rate by nuclear transfer of cells that have been transfected with huKO using a retroviral vector, and that it is possible to observe the expression of red fluorescence in cloned embryos. With respect to the cloned embryos that did not show expression of red fluorescence, we hypothesize that this was the result of a small proportion (&lt;1&percnt;) of donor cells which also lacked red fluorescence expression. An ultrasonic echo examination has confirmed that all 3 of the recipients which had received 93 to 119 embryos became pregnant. This study was supported by PROBRAIN.

A BTB/POZ protein, NAC-1, is related to tumor recurrence and is essential for tumor growth and survival

Recent studies have suggested an oncogenic role of the BTB/POZ-domain genes in hematopoietic malignancy. The aim of this study is to identify and characterize BTB/POZ-domain genes in the development of human epithelial cancers, i.e., carcinomas. In this study, we focused on ovarian carcinoma and analyzed gene expression levels using the serial analysis of gene expression (SAGE) data in all 130 deduced BTB/POZ genes. Our analysis reveals that NAC-1 is significantly overexpressed in ovarian serous carcinomas and several other types of carcinomas. Immunohistochemistry studies in ovarian serous carcinomas demonstrate that NAC-1 is localized in discrete nuclear bodies (tentatively named NAC-1 bodies), and the levels of NAC-1 expression correlate with tumor recurrence. Furthermore, intense NAC-1 immunoreactivity in primary tumors predicts early recurrence in ovarian cancer. Both coimmunoprecipitation and double immunofluorescence staining demonstrate that NAC-1 molecules homooligomerize through the BTB/POZ domain. Induced expression of the NAC-1 mutant containing only the BTB/POZ domain disrupts NAC-1 bodies, prevents tumor formation, and promotes tumor cell apoptosis in established tumors in a mouse xenograft model. Overexpression of full-length NAC-1 enhanced tumorigenicity of ovarian surface epithelial cells and NIH 3T3 cells in athymic nu/nu mice. In summary, NAC-1 is a tumor recurrence-associated gene with oncogenic potential, and the interaction between BTB/POZ domains of NAC-1 proteins is critical to form the discrete NAC-1 nuclear bodies and essential for tumor cell proliferation and survival.

Sequence mutations and amplification of PIK3CA and AKT2 genes in purified ovarian serous neoplasms

Sequence mutations and gene amplifications lead to activation of the PIK3CA-AKT2 signaling pathway and have been reported in several types of neoplasms including ovarian cancer. Analysis of such genetic alterations, however, is usually complicated by contamination of normal cell DNA, artifacts associated with formalin-fixed tissues and the sensitivity of the techniques employed. In this study, we analyzed the sequence mutations in PIK3CA and AKT2 genes using purified tumor cells that were isolated from high-grade ovarian serous carcinomas and serous borderline tumors (SBTs) and assessed gene amplification using a dual-color FISH on tissue microarrays. Somatic sequence mutations in the kinase domain of AKT2 were not detected in any of the 65 ovarian tumors analyzed. Mutations of PIK3CA were rare, occurring only in one (2.3%) of 44 high-grade serous carcinomas and in only one (4.8%) of 21 SBTs. Dual-color FISH demonstrated that PIK3CA and AKT2 were not amplified in SBTs but amplified in 13.3% and 18.2% high-grade carcinomas, respectively. High-level amplification (>3 fold) was more frequently observed in AKT2 than in PIK3CA. Unlike mutations in ERBB2, KRAS and BRAF which are mutually exclusive in SBTs, coamplification of PIK3CA and AKT2 was present in five high-grade carcinomas including the OVCAR3 cells. Amplification in either of the genes occurred in 27% high-grade serous carcinomas. In conclusion, the methods we employed provide unambiguous evidence that somatic sequence mutations of PIK3CA and ATK2 are rare in ovarian serous tumors but amplification of both genes may play an important role in the development of high-grade ovarian serous carcinoma.

Relationship between regional cerebral metabolism and consciousness disturbance in traumatic diffuse brain injury without large focal lesions: an FDG-PET study with statistical parametric mapping analysis

BACKGROUND

The cerebral metabolism of patients in the chronic stage of traumatic diffuse brain injury (TDBI) has not been fully investigated.

AIM

To study the relationship between regional cerebral metabolism (rCM) and consciousness disturbance in patients with TDBI.

METHODS

52 patients with TDBI in the chronic stage without large focal lesions were enrolled, and rCM was evaluated by fluorine-18-fluorodeoxyglucose positron emission tomography (FDG-PET) with statistical parametric mapping (SPM). All the patients were found to have disturbed consciousness or cognitive function and were divided into the following three groups: group A (n = 22), patients in a state with higher brain dysfunction; group B (n = 13), patients in a minimally conscious state; and group C (n = 17), patients in a vegetative state. rCM patterns on FDG-PET among these groups were evaluated and compared with those of normal control subjects on statistical parametric maps.

RESULTS

Hypometabolism was consistently indicated bilaterally in the medial prefrontal regions, the medial frontobasal regions, the cingulate gyrus and the thalamus. Hypometabolism in these regions was the most widespread and prominent in group C, and that in group B was more widespread and prominent than that in group A.

CONCLUSIONS

Bilateral hypometabolism in the medial prefrontal regions, the medial frontobasal regions, the cingulate gyrus and the thalamus may reflect the clinical deterioration of TDBI, which is due to functional and structural disconnections of neural networks rather than due to direct cerebral focal contusion.