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Glypican-3 (GPC3) is expressed in most hepatocellular carcinomas (HCCs). To investigate the significance of various GPC3 staining patterns in HCC, we classified 134 HCC patients into three groups: those with diffuse GPC3 staining, canalicular GPC3 staining, and others (including negative staining). HCCs with diffuse staining were correlated with poor differentiation, high Ki-67 indices, high serum α-fetoprotein (AFP) levels, and early recurrence. In contrast, HCCs with canalicular staining were well differentiated with lower AFP levels. Overall survival in this group was better than that of the other two groups. Comparative analysis of GPC3 staining patterns with markers for HCC subclassification showed that diffuse staining was correlated with the expression of biliary/stem cell markers, whereas canalicular staining was correlated with expression of the markers of WNT-activated HCCs. Induction of leucine-rich repeat-containing G-protein-coupled receptor 5 (LGR5), known as a target of the WNT signaling pathway, in HCC cells resulted in reduced GPC3 expression in vitro. The LGR5-induced cells formed tumors with canaliculus-like structures in mice and showed canalicular GPC3 staining. The current findings showed the significance of recognizing distinct GPC3 staining patterns, i.e., diffuse and canalicular, which may reflect different carcinogenetic mechanisms and indicate the level of malignancy of HCC.

Activation of the Hedgehog (HH) signaling pathway plays a critical role in the development of basal cell carcinoma (BCC). HH signaling activity is produced by nuclear translocation of transcription factors, glioma-associated oncogene homolog (GLI). Among three GLI subfamilies, GLI1 is the only full-length transcriptional activator, and its nuclear localization is recognized as a signature event in HH signaling activation. However, limited published work has investigated the nuclear staining of GLI1 protein in human tumor tissue samples by immunohistochemical analysis. In this study, we performed immunohistochemical staining of GLI1 in 382 cases of cutaneous epithelial tumors, including 196 BCC cases, using rabbit monoclonal antihuman GLI1 antibody (C68H3). As a result, 98.2% cases of BCC showed a diffuse and strong nuclear staining pattern regardless of the histological subtype. Positive staining was mainly restricted to the tumor nests, while the overlying epidermis was negative suggesting specificity of the antibody. In further analysis of other cutaneous epithelial tumors, 100% (4/4) cases of trichoblastoma, 15.1% (5/33) Bowen's disease, 3.5% (1/28) actinic keratosis and 12.5% (4/32) squamous cell carcinoma showed the nuclear staining pattern of GLI1. This suggested that HH signaling is also dysregulated in some other cutaneous malignant tumors. In conclusion, the C68H3 antibody is a useful tool for revealing activation of HH signaling in immunohistochemical analysis.

The leucine-rich repeat containing G protein-coupled receptor 5 (LGR5), also known as GPR49, is a seven-transmembrane receptor that is expressed in stem cells of the intestinal crypts and hair follicles of mice. LGR5 is overexpressed in some types of human cancer, and is one of the target genes of the Wnt signaling pathway. To explore the function of LGR5 in cancer cells, stable hepatocellular carcinoma (HCC) cell lines expressing FLAG-tagged LGR5 were established. Overexpression of LGR5 resulted in changes in cell shape from an extended flat (mesenchymal) phenotype to a round aggregated (stem cell-like) phenotype. Cells transfected with LGR5 showed higher colony forming activity, and were more resistant to a cytotoxic drug than cells transfected with empty vector. Overexpression of LGR5 inhibited cell motility. LGR5-transfected cells formed nodule type tumors in the livers of immunodeficient mice, whereas empty vector-transfected cells formed more invasive tumors. Down-regulation of LGR5 changed the morphology of HCC cells from the aggregated phenotype to an extended spindle phenotype, and cell motility was increased. This is the first study reporting the functional role of LGR5 in the biology of HCC cells, and the results suggest that aberrant expression of LGR5 regulates epithelial cell phenotype and survival.

Gastric cancer is one of the most common malignancies worldwide and patients with advanced gastric cancer still have poor clinical outcomes. The overexpression of leucine-rich repeat-containing G protein-coupled receptor 5 (LGR5) mRNA in colorectal cancer and its correlation with clinicopathological factors were recently reported by us. In this study, we show LGR5 mRNA overexpression in human gastric cancer specimens by quantitative RT-PCR and in situ hybridization and assess a correlation with clinicopathological factors. The mean expression of LGR5 mRNA in cancerous tissues was five times higher than that in normal tissue (P = 0.0002). Furthermore, LGR5 mRNA expression show marked variation among cases and significantly increased in cases where lymphatic invasion was present compared with those where it was absent (P = 0.0056). Although the mean expression level of LGR5 was observed to be higher in nodal metastasis and venous invasion positive cases compared to negative cases, a significant difference was not observed. These results suggest that LGR5 can be a biomarker for malignancy in gastric cancer.

Leucine-rich repeat-containing G protein-coupled receptor 5 (LGR5) is a 7-transmembrane receptor reportedly expressed in stem cells of the intestinal crypts and hair follicles of mice. Overexpression of LGR5 is observed in some types of cancer; however, there has been no specific assessment in colorectal tumorigenesis. We performed quantitative RT-PCR for LGR5 expression in 37 representative cancer cell lines, and showed that LGR5 mRNA was frequently overexpressed in colon cancer cell lines. Moreover, LGR5 expression was higher in colon cancer cell lines derived from metastatic tumors compared with those from primary tumors. In clinical specimens, there was significant overexpression of LGR5 in 35 of 50 colorectal cancers (CRCs), and in seven of seven sporadic colonic adenomas, compared with matched normal mucosa. This suggests up-regulation of LGR5 from the early stage of colorectal tumorigenesis. LGR5 expression showed marked variation among CRC cases and correlated significantly with lymphatic invasion, vascular invasion, tumor depth, lymph node metastasis, and tumor stage (IIIC vs. IIIB). In addition to cancer cells, crypt base columnar cells of the small intestine and colon were shown by in situ hybridization to express LGR5. This is the first report suggesting the involvement of LGR5, not only in early events but also in late events in colorectal tumorigenesis.

Background: Hepatocellular carcinoma (HCC) is one of the most common and most frequently lethal cancers worldwide. Although many advances have been made in the analysis of multistage hepatocarcinogenesis, we still lack information to guide adequate clinical management options for HCC. A large number of genetic alterations occur during hepatocarcinogenesis, and many genetic studies have indicated that one of the most frequently mutated oncogenes found in HCC is β-catenin. Summary: Molecular subclassification of HCC based on gene expression signatures has identified a typical hepatocyte-like subclass of HCC harboring β-catenin mutations; this subclass is characterized by better histological differentiation and a less aggressive nature. We previously identified overexpression of the leucine-rich repeat-containing G protein-coupled receptor 5 (LGR5), also known as GPR49, in HCC with β-catenin mutations. LGR5 has been indicated as one of the downstream target genes of the Wnt signaling pathway; however, the functional role of LGR5 in cancer is largely unknown. We demonstrated that HCC cells transfected with LGR5 exhibited higher colony forming activity and were more resistant to a cytotoxic drug than the control HCC cells were. Overexpression of LGR5 also retarded cell migration. LGR5-transfected HCC cells formed nodule-type tumors in the livers of immunodeficient mice, whereas control cells formed more invasive tumors. Results of our recent research suggest that aberrant expression of LGR5 could regulate the epithelial cell phenotype and promotes HCC cell survival. HCC cells overexpressing LGR5 seem to represent a typical phenotype of a less aggressive HCC. Key messages: Recent efforts on the molecular classification of HCC have led us to new strategies for dealing with HCC. These specific signatures may predict the risk of recurrence or the patient survival rate, which affect the outlook and may suggest treatment strategies for HCC patients.

Purpose: Perineural invasion causes frequent local recurrence even after resection and a poor prognosis for pancreatic cancer. We established perineural invasion models and analyzed the molecular mechanism of perineural invasion in pancreatic cancer.Experimental Design: Seven pancreatic cancer cell lines with or without human peripheral nerves were s.c. implanted in nonobese diabetes/severe combined immunodeficient mice. We compared expression profiles among high and low perineural invasion cell lines by using an oligonucleotide microarray. We examined up-regulation of the invariant chain (CD74) in high perineural invasion cell lines in mRNA and protein levels and surgical cases immunohistochemically.Results: Four of seven pancreatic cancer cell lines (CaPan1, CaPan2, CFPAC, and MPanc96) showed perineural invasion to s.c. transplanted human peripheral nerves. Moreover, CaPan1 and CaPan2 (high perineural invasion group) also resulted in a high frequency of perineural invasion to mouse s.c. peripheral nerves, whereas three pancreatic cancer cell lines HPAFII, AsPC1, and Panc1 (low perineural invasion group) did not show perineural invasion to either human or mouse nerves. We identified 37 up-regulated genes and 12 down-regulated genes in the high perineural invasion group compared with the low perineural invasion group. Among them, CD74 was up-regulated in the high perineural invasion group in mRNA and protein levels. Furthermore, immunohistochemical expression of CD74 in clinical cases revealed its significant overexpression in pancreatic cancer with perineural invasion (P < 0.008).Conclusions: This is the first report of perineural invasion models using human pancreatic cancer cell lines. In combination with gene expression profiling, it was indicated that CD74 could be a candidate molecule involved in perineural invasion. These models provide new approaches for study of perineural invasion in pancreatic cancer.

In Wolfram syndrome, a rare form of juvenile diabetes, pancreatic beta-cell death is not accompanied by an autoimmune response. Although it has been reported that mutations in the WFS1 gene are responsible for the development of this syndrome, the precise molecular mechanisms underlying beta-cell death caused by the WFS1 mutations remain unknown. Here we report that WFS1 is a novel component of the unfolded protein response and has an important function in maintaining homeostasis of the endoplasmic reticulum (ER) in pancreatic beta-cells. WFS1 encodes a transmembrane glyco-protein in the ER. WFS1 mRNA and protein are induced by ER stress. The expression of WFS1 is regulated by inositol requiring 1 and PKR-like ER kinase, central regulators of the unfolded protein response. WFS1 is normally up-regulated during insulin secretion, whereas inactivation of WFS1 in beta-cells causes ER stress and beta-cell dysfunction. These results indicate that the pathogenesis of Wolfram syndrome involves chronic ER stress in pancreatic beta-cells caused by the loss of function of WFS1.

Ewing sarcoma is a malignant bone and soft tissue tumor of children and young adults, which is known to be highly aggressive and invasive. It expresses specific chimeric genes (EWS-FLI-1, EWS-ERG, EWS-ETV1, and EWS-E1AF), the 3′ portions of which are all members of the ETS family. ETS-related proteins, such as FLI-1, ERG, and E1AF, transactivate the promoters of matrix metalloproteinase (MMP) genes, which play important roles in the processes of invasion and metastasis. Therefore, we hypothesize that the Ewing sarcoma-specific chimeric genes also transactivate the MMP genes, contributing to the tumor's invasiveness and propensity for metastasis. To verify this hypothesis, we investigated the expression of MMPs in eight Ewing sarcoma cell lines. Surprisingly, MMP-1 and MMP-3 were not expressed at all in any of the cell lines. MMP-9 was expressed in four out of the eight cell lines, and MMP-2 and MT1-MMP in all of the cell lines. Ewing sarcoma-specific chimeric genes have been shown to transactivate the promoter of the MMP-1 gene by the reporter assay, and bind to the putative recognition sites in the MMP regulatory elements by the gel shift assay. However, an in vivo formaldehyde cross-linking study revealed that the chimeric protein did not bind to the predicted ETS recognition sites in the regulatory elements of the MMPs. These results indicate that the absence of the MMP expression in the tumor cells is at least in part due to the loss of accessibility of the ETS recognition sites in the regulatory elements of the MMP genes. Therefore, we should be careful before theorizing simply that a putative binding site is essential for the transcription of critical genes, since the binding of this fusion protein was found to be modulated in tumor cells in this study.

Differentiation and apoptosis are precisely regulated events in early embryogenesis. Retinoic acid-induced differentiation in the embryonal carcinoma (EC) cell line NCR-G3 triggers concurrent induction of apoptosis. Using this system, which serves as a model of early embryogenesis, the expression of various bcl-2-related genes was analyzed as these genes display either positive or negative regulatory effects on apoptosis. EAT/mcl-1, an antiapoptotic bcl-2-related gene and immediate early gene, was dramatically expressed at an early stage of NCR-G3 differentiation. Bcl-xL, another antiapoptotic gene, was induced at a middle stage of differentiation and then gradually decreased to basal level. Expression of Bax, a proapoptotic molecule, was detected at a high level and remained relatively constant. Meanwhile, Bcl-2 and Bcl-xS were below detectable levels throughout the various stages of differentiation. As the balance of bcl-2 genes is a crucial regulatory step in apoptosis, the results suggest that EAT and Bax likely regulate apoptosis in the early stages of differentiation. In later stages of differentiation, down-regulation of EAT was found to coincide with a gradual increase in apoptosis of NCR-G3 cells. Furthermore, use of the monoclonal antibody (3A2) specific to EAT revealed that EAT is localized to the outer mitochondrial membrane in human EC cells. In addition, EAT immunoreactivity was not detected in apoptotic NCR-G3 cells while it was observed in nearly all viable cells. The findings suggest that rapid induction of EAT may prevent NCR-G3 cells from undergoing apoptosis, thereby supporting viability at the early stage of differentiation.

The Gal11 protein is a subunit of the Mediator complex. Biochemical as well as genetic studies have strongly suggested that Gal11 is a positive global regulator of transcription. Some reports argue that Gal11 is a negative regulator, however. Here we have adopted the "Mini-array membrane hybridization" to analyze the effect of Gal11 in a genome-wide fashion. This technique has been demonstrated to be reliable to identify genes whose expression is controlled by a specific set of genetic and/or physiological signals. Our experiments indicate that this technique is applicable to profile the gene expression in yeast grown in rich medium. Thus mRNAs of 40% of significantly expressed genes are reduced more than two fold in gal11null yeast, in which only 3% of mRNAs are increased more than two fold. These results strongly suggest that Gal11 functions globally as a positive regulator in vivo.

The GAL3 gene plays a critical role in galactose induction of the GAL genes that encode galactose- metabolizing enzymes in Saccharomyces cerevisiae. Defects in GAL3 result in a long delay in GAL gene induction, and overproduction of Gal3p causes constitutive expression of GAL. Here we demonstrate that concomitant overproduction of the negative regulator, Gal80p, and Gal3p suppresses this constitutive GAL expression. This interplay between Gal80p and Gal3p is direct, as tagged Gal3p coimmunoprecipitated with Gal80p. The amount of coprecipitated Gal80p increased when GAL80 yeast cells were grown in the presence of galactose. When both GAL80 and GAL3 were overexpressed, the amount of coprecipitated Gal80p was not affected by galactose. Tagged gal3 mutant proteins bound to purified Gal80p, but only poorly in comparison with the wild type, suggesting that formation of the Gal80p-Gal3p complex depends on the normal function of Gal3p. Gal3p appeared larger in Western blots (immunoblots) than predicted by the published nucleic acid sequence. Reexamination of the DNA sequence of GAL3 revealed several mistakes, including an extension at the 3' end of another predicted 97 amino acids.

Gastric cancer is one of the most common malignancies worldwide and patients with advanced gastric cancer still have poor clinical outcomes. The overexpression of leucine-rich repeat-containing G protein-coupled receptor 5 (LGR5) mRNA in colorectal cancer and its correlation with clinicopathological factors were recently reported by us. In this study, we show LGR5 mRNA overexpression in human gastric cancer specimens by quantitative RT-PCR and in situ hybridization and assess a correlation with clinicopathological factors. The mean expression of LGR5 mRNA in cancerous tissues was five times higher than that in normal tissue (P = 0.0002). Furthermore, LGR5 mRNA expression show marked variation among cases and significantly increased in cases where lymphatic invasion was present compared with those where it was absent (P = 0.0056). Although the mean expression level of LGR5 was observed to be higher in nodal metastasis and venous invasion positive cases compared to negative cases, a significant difference was not observed. These results suggest that LGR5 can be a biomarker for malignancy in gastric cancer.

Vasoactive peptide endothelins are a group of small peptides with diverse paracrine/autocrine actions and are reported to be involved in the pathogenesis of many human malignancies. Basal cell carcinoma (BCC) is a common malignant skin tumor that frequently has aberrant activation of the Hedgehog (HH) signaling pathway. We show here that endothelin-2 (ET-2) is overexpressed in BCC under the control of HH signaling. By real-time quantitative RT-PCR analysis, significant expression of ET-2 mRNA was observed in 19 of 20 cases (95%) compared to normal skin. In addition, inhibition of the HH signaling pathway in a mouse BCC cell line downregulated endogenous ET-2, and activation of HH signaling in mouse embryonic fibroblast upregulated endogenous ET-2. Moreover, the 3′ promoter region of ET-2 gene contains the GLI-binding site and a 0.8 kb downstream fragment containing GLI-binding sites activates transcription in a reporter assay. These data indicate that ET-2 is a direct target gene of HH signaling in BCC.

Purpose: Perineural invasion is associated with the high incidence of local recurrence and a dismal prognosis in pancreatic cancer. We previously reported a novel perineural invasion model and distinguished high– and low–perineural invasion groups in pancreatic cancer cell lines. This study aimed to elucidate the molecular mechanism of perineural invasion. Experimental Design: To identify key biological markers involved in perineural invasion, differentially expressed molecules were investigated by proteomics and transcriptomics. Synuclein-γ emerged as the only up-regulated molecule in high–perineural invasion group by both analyses. The clinical significance and the biological property of synuclein-γ were examined in 62 resected cases of pancreatic cancer and mouse models. Results: Synuclein-γ overexpression was observed in 38 (61%) cases and correlated with major invasive parameters, including perineural invasion and lymph node metastasis (P < 0.05). Multivariate analyses revealed synuclein-γ overexpression as the only independent predictor of diminished overall survival [hazard ratio, 3.4 (95% confidence interval, 1.51-7.51)] and the strongest negative indicator of disease-free survival [2.8 (1.26-6.02)]. In mouse perineural invasion and orthotopic transplantation models, stable synuclein-γ suppression by short hairpin RNA significantly reduced the incidence of perineural invasion (P = 0.009) and liver/lymph node metastasis (P = 0.019 and P = 0.020, respectively) compared with the control. Conclusions: This is the first study to provide in vivo evidence that synuclein-γ is closely involved in perineural invasion/distant metastasis and is a significant prognostic factor in pancreatic cancer. Synuclein-γ may serve as a promising molecular target of early diagnosis and anticancer therapy.

The significance of Hedgehog (HH) signaling in the development of basal cell carcinoma (BCC) has been established. Although several target genes of HH signaling have been described previously, their precise role in tumorigenesis and cell proliferation is not yet known. To identify genes responsible for tumor formation in BCC, we screened a DNA microarray database of human BCC cases; the orphan G-protein-coupled receptor GPR49 was found to be up-regulated in all cases. GPR49 is a novel gene reported to be a marker of follicular and other tissue stem cells. Using real-time quantitative RT-PCR analysis, significant expression of GPR49 mRNA was observed in 19 of 20 BCC cases (95%) compared with controls. Up-regulation of GPR49 was confirmed by in situ hybridization. Moreover, knockdown of mouse Gpr49 showed suppression of cell proliferation in a mouse BCC cell line, and overexpression of GPR49 in human immortalized keratinocyte HaCaT cells induced proliferation. Furthermore, HaCaT cells overexpressing GPR49 showed tumor formation when transplanted into immunodeficient mice. In addition, inhibition of the HH signaling pathway in a mouse BCC cell line down-regulated endogenous Gpr49, whereas activation of HH signaling in mouse NIH3T3 cells up-regulated endogenous GPR49. These results suggest that GPR49 is expressed downstream of HH signaling and promotes cell proliferation and tumor formation in cases of BCC.

有機ケイ素化合物の抗腫瘍活性を培養細胞系と実験動物移植腫瘍系を用いて検討した。50種類の化合物には培養細胞系においてEhrlichがん,肉腫-180.Lewis肺がんおよびB-16メラノーマに対して細胞増殖抑制効果を示す化合物が認められ,また,マウス移植腫瘍系においても上記の各固形腫瘍に対して経口投与によって有効な抗腫瘍活性を現わす化合物が見いだされた.中でも2-(2-Trimethylsilylethy1)thiaethylamine(SDK-12A)は最も強い活性を示し,その効果は抗がん剤5-FUのそれに匹敵するものであった。さらに,SDK-12AはLewis肺がんの転移を有意に抑制し.遅延型免疫機能賦活化作用も認められた。またSDK-12Aは実験動物において毒性面では安全性の高い化合物であった。これらの結果は,SDK-12Aが多面的作用を持った特異な化合物であり,抗がん剤開発の研究領域からみて興味ある物質である。

Carcinosarcoma of gallbladder, also named sarcomatoid carcinoma and spindle cell carcinoma, is a rare neoplasm. Its clinical features and prognostic determinants are still poorly understood due to its rarity. We identified 67 qualified cases in published literatures and 1 in our institution. 52 of them were females and 16 males (F:M=3.25:1). 27 were Japanese patients and the rest were mainly from the United States and Europe. The mean age was 68.8 years (median 68 years, range 45-91 years). The average tumor size was 6.9 cm (median 5 cm, range 1.0-24.0 cm, n=49). Adenocarcinoma was the most common epithelial component (79.2%) and squamous cell carcinoma was the least common (9.4%). Spindle cell type was the most common mesenchymal component (44.6%) and osteoid was the least common (5.4%). The mean survival was 17.5 months (median 5 months, range 0 to 85 months, n=56). The 1-year and 5-year survival rates were 19+/-5% and 16+/-5% (mean+/-SD), respectively. Kaplan Meier survival analysis was conducted to examine the prognostic value of various clinical parameters. We found Japanese patients had longer survival time than non-Japanese ones (mean=19.9 months vs 11.5 months, median=6 vs 4 months, n=27 vs 24, p=0.022). Patients with smaller tumor (5.0 cm) had longer survival time (in months) than those with larger tumor (mean 26.6 vs 17.7, median 11 vs 5, n=14 vs 27, p=0.028). The presence of gallstone, epithelial and mesenchymal component types, age and sex of the patients were not significant prognostic factors. In summary, race (Japanese vs non-Japanese) and tumor size are important prognostic factors in carcinosarcoma of gallbladder and they may be used for prognostification.

Germ cell tumours, the most common solid cancers in young males, display pluripotentiality for embryonal and somatic differentiation. Specific surface antigens are useful in the study of cellular differentiation and for clinical diagnosis. A mouse monoclonal antibody (4C4-mAb) has been developed against a human embryonal carcinoma (EC) cell line (NCR-G3) isolated from a combined form of testicular germ cell tumour. On immunohistological and immuno-electron microscopic examination, the 4C4 antigen (4C4) was detected on the surface of NCR-G3 and gold particles were exclusively detected on the microvilli of the cells. In both formalin-fixed paraffin wax sections and touch-smear specimens, 4C4 was detected specifically in EC, while the antigen was not expressed in other types of germ cell tumour or in the other solid tumours tested. Tunicamycin diminished the antigenicity of NCR-G3 cells. In biochemical studies, 4C4 was found in a high molecular weight region ranging from 1 x 10(6) to 1 x 10(7) kD, which disappeared after periodate treatment. The density of 4C4 was 1.5 g/cm(3) after equilibrium centrifugation. These results imply that 4C4 is a proteoglycan. Furthermore, endo- and exo-glycosidase treatment revealed that 4C4 is a keratan sulphate proteoglycan that contains sialyl and fucosyl moieties. With EC-specific and formalin-resistant characteristics, 4C4 may be a specific marker for diagnosing EC among a variety of germ cell tumours.

EAT/mcl-1 (EAT), a bcl-2 related anti-apoptotic gene, is up-regulated at the early stage of differentiation of human embryonal carcinoma cells; cells which serve as a model for early embryogenesis. We generated transgenic mice for the human EAT gene driven by the EF1 alpha promoter in order to elucidate its functional role in vivo. Histologically, these mice exhibited hyperplasia of Langerhans islet cells; pancreatic cell regions composed of both insulin- and glucagon-producing cells. Furthermore, Bax and Bag-1 -- possible heterodimeric partners for EAT in the anti-apoptotic process -- were up-regulated in islets isolated from the EAT transgenic mice. The insulin tolerance test exhibited no significant difference between the EAT transgenic mice and non-transgenic mice, indicating that islet cell hyperplasia was not due to insulin resistance. In conclusion, EAT transgenic mice exhibit hyperplasia of pancreatic beta cells. EAT may inhibit apoptosis of beta cells, allowing these cells to circumvent the process of apoptosis until the adult stage.

The chromosomal translocation specifically linked to the Ewing sarcoma family results in the generation of fusion proteins comprising the amino terminal portion of EWS and the DNA-binding domain of ets transcription factors. The EWS/ets chimeric proteins act as aberrant transcription factors leading to tumorigenic processes. We searched for genes specifically activated in Ewing sarcoma cells but not in other tumor cell lines using the gene array technique, and found significantly enhanced expression of the Id2 gene. High levels of Id2 transcripts were detected in Ewing sarcoma cell lines and tumor tissues. The EWS/ets chimeric proteins activated the Id2 gene via the 5'-upstream promoter sequence. Chromatin-immunoprecipitation revealed a direct interaction of EWS/Fli-1 with the promoter regions of the Id2, TGF-beta type II receptor, cyclin D1, and c-myc genes. Since EWS/Fli-1 transactivates c-myc, a cooperative action of the chimeric protein and c-myc leads to overexpression of Id2. In the present study, we suggest that Id2 is a target of the chimeric proteins and that the c-myc/Id2 pathway plays a pivotal role in the tumorigenic processes provoked by EWS/ets proteins.

Apoptosis plays an important regulatory role in mammalian embryogenesis and development. EAT/mcl-1 (EAT), an anti-apoptotic bcl-2-related gene, was isolated during the early differentiation of a human embryonal carcinoma cell line, an event which serves as a model of early embryogenesis. EAT is involved in apoptotic regulation and is believed to also function as an immediate-early gene. Thus it was hypothesized that EAT would be expressed during early embryogenesis and would be involved in the regulation of apoptosis during this critical period. To clarify this early expression, two antibodies to EAT were generated by use of immunizing oligopeptide (aa 37-55) and recombinant protein (aa 31-229) for use in immunohistochemistry and immunoblotting, respectively. With these antibodies, we then determined EAT expression during murine embryogenesis and in human development, using human fetal tissue of 6 to 23 gestational weeks. During murine embryogenesis, the EAT protein was found to be rapidly induced after fertilization, to peak at the 2-cell stage, to remain constant until the 8-cell stage, and then to decrease to below unfertilized egg levels in blastocysts. EAT expression patterns in early human development were found to essentially overlap those observed in adult tissues which suggest that EAT expression continues until adulthood in terminally differentiated tissues. Among tissues distinct to fetal development, EAT was detected in the mesonephric (Wolffian) duct and paramesonephric (Mullerian) duct. It is also noteworthy that prominent EAT immunoreactivity was also observed in large primary oocytes in 21-week fetal ovary, but was not detected in primordial germ cells in 23-week fetal testis. In summary, EAT expression was detected in hematopoietic, epithelial, neural, endocrine, and urogenital cells; this provides evidence that EAT, as an anti-apoptotic molecule, possibly functions to regulate apoptosis during development in these systems.

Jumping translocations (JTs) are unbalanced chromosomal translocations in which an identical chromosomal region is translocated to the telomeric region of different chromosomes. JTs are rare in hematological malignancies where they are second translocations and may be an indicator of poor prognosis. We report a case of acute myeloid leukemia with t(16;21) and a JT in which the long arm of chromosome 1 distal to q21 is translocated to the terminal region of chromosome 10. The leukemic cells exhibit high expression of EAT/mcl1, an anti-apoptotic Bcl-2 related gene. Since EAT/mcl1 is mapped to 1q21 near the breakpoint in the JTs, high level expression of EAT/mcl1 may be associated with the poor prognosis of leukemia with JTs.

We have developed a procedure to purify nucleosomal assembly-competent histones as a mixture of H2A, H2B, H3 and H4 from isolated nuclei of the yeast Saccharomyces cerevisiae with a purity of 70-80%. The mixture contained each of the histone subunits approximately at the equi-molar ratio. Plasmid pBR322 DNA was assembled into nucleosomes with the purified yeast histones in the presence of nucleoplasmin from unfertilized eggs of the frog Xenopus laevis. The efficiency of assembly of yeast histones was comparable to that of core histones purified from HeLa cells. The length of DNA fragment wrapping around a core histone particle and the molar ratio of histone components in an assembled nucleosome particle were estimated to be 150 +/- 10 bp long and H2A:H2B:H3:H4 = 1.0:0.9:0:9:1.0, respectively.

Polyoxotungstates with Keggin-type structure were found to demonstrate marked antiherpetic activity. K 7 [Ti 2 W 10 PO 40 ]·6H 2 O (PM-19) caused a decrease in plaque formation by several strains of herpes simplex virus (HSV) type 1, including acyclovir-resistant (thymidine kinase-negative) strains, at concentrations which were not toxic to the host cells. The 50% plaque-inhibiting concentration (EC 50 ) for the different strains was between 20 and 50 μg/ml. Single-cycle HSV growth was also inhibited by PM-19. PM-19 inhibited viral DNA synthesis in HSV-infected cells at a concentration of 5 μg/ml but did not exhibit a virucidal effect, and pretreatment of the host cells with PM-19 did not provide resistance to herpes infection. Yet, virus adsorption to the cells was markedly affected at PM-19 concentrations higher than 25 μg/ml. PM-19 was also effective against human cytomegalovirus, but not against adenoviruses and varicella-zoster virus, although it did delay the development of the cytopathic effect of these viruses.

Environmental substances were examined for their effect on interferon induction and delayed type hypersensitivity (DTH) responses in mice. Amaranth, safrole, phenacetin and nicotine suppressed the DTH response, and suppressed the serum interferon titers induced by virus infection. However, they did not affect the interferon titers which were induced by tilorone, a chemical inducer. The peak of interferon titer was 12 hours after infection with herpes simplex virus type 2 (HSV-2). Therefore, amaranth, safrole, phenacetin and nicotine were given to mice intraperitoneally 24 hours before, and 2 and 18 hours after infection with HSV-2. It was found that safrole and nicotine shortened the mean survival time of HSV-2 infected mice when they were given to mice 2 hours after virus inoculation. Amaranth and phenacetin showed similar effects. However it was not definite statistically. In biochemical and hematological tests, these four substances did not affect the functions of liver, kidney and carbohydrate metabolism in normal mice. These results suggest that substances which may often be taken into the body have the potential to affect the onset of virus infectious diseases as a result of the suppression of the host defense reaction.

N-Benzoyl-DL-phenylalanine (1) was found to possess hypoglycemic activity. A series of the analogues of compound 1 were prepared and evaluated for their blood glucose lowering activity. Both the steric effects of the phenylalanine moiety and the effects of variations in the acyl moiety were investigated. This study elucidated some of the structure-activity relationships and led to the development of N-(4-ethylbenzoyl)-D-phenylalanine (34), which was 50 times more potent than the initial compound 1.

A series of analogues of N-(cyclohexylcarbonyl)-D-phenylalanine (5) have been synthesized and evaluated for their hypoglycemic activity. Relationships were studied between the activity and the three-dimensional structure of the acyl moiety, which was characterized by high-resolution 1H NMR spectroscopy and MNDO calculations. The role of the carboxyl group of the phenylalanine moiety was also studied by comparing the activities of the enantiomers, the decarboxyl derivative, the esters, and the amides of the phenylalanine derivatives. Thus, the structural requirements for possessing hypoglycemic activity was elucidated and a highly active compound, N-[(trans-4-isopropylcyclohexyl)carbonyl]-D-phenylalanine (13) was obtained, which showed a 20% blood glucose decrease at an oral dose of 1.6 mg/kg in fasted normal mice.

BACKGROUND/AIM—EAT/mcl-1 (EAT), an immediate early gene, functions in a similar way to bcl-2 in neutralising Bax mediated cytotoxicity, suggesting that EAT is a blocker of cell death. The aim of this study was to determine the effect of overexpression of the human EAT gene on light induced retinal cell apoptosis. METHODS—EAT transgenic mice incorporating the EF-1α promoter were utilised, and expression of human EAT was detected by RT-PCR. Light damage was induced by raising mice under constant illumination. Two groups of animals, EAT transgenic mice (n=14) and littermates (n=13), were examined by ERG testing and histopathology at regular time points up to 20 weeks of constant light stimulation. Electrophysiological and histopathological findings were evaluated by established systems of arbitrary scoring as scores 0-2 and scores 0-3, respectively. RESULTS—The mean score (SD) of ERG response was significantly lower in EAT transgenic mice (0.79 (0.89)) than in littermates (1.69 (0.48)) (p

Some enviromental substances to which we are exposed in everyday life are involved in the onset of chronic disease. This study was performed to clarify whether nicotine plays a role in the development of diabetes mellitus(DM). We used mice in two phases of DM. Prediabetic mice (SZ mice) induced by streptozoto-cin(SZ) at a subdiabetogenic dose(50 mg/kg, iv) had normal blood glucose levels(BGL) and impared glucose tolerance (IGT). Supre-diabetic mice (CP-44) induced by the infection with a pancreatropic variant of Venezuelan encephalitis (VE) virus, CP-44, had normal BGL and diminished insulin release(DIR) in GTT. Nicotine administration was performed by 2 routes: ip (0.03-0.4 mg/kg/day) and po, ad libitum (ab. 10 and 42 mg/kg/day). In ip-groups, prediabetic SZ mice (ICR) showed significantly high BGL at 0.1 mg of nicotine for 1 month;but 6 months later, SZ mice administered nicotine at the dose of 0.4 mg/kg/day recovered. Supredi a bet ic CP-44 mice (ICR) showed significantly high BGL at 0.1 mg of nicotine for 1 month and recovered at higher doses of nicotine by 6 months. In po-groups in which C D F -j mice were used, all SZ mice administered nicotine showed significantly higher BGL. CP-44 mice showed significantly higher BGL, regardless of nicotine administration. The pathology and other biochemical alterations are under the study.

Effect of enviromental factors on reactivation of latent HSV are investigated using in vitro models reported by Y. Nishiyama (1981) with slight modifications. U. V. - irradiated herpes simplex virus (HSV) type 2 strain 169 and Flow 2000 as human embryonic lung cells were employed through this study. Latent HSV-2 were reactivated by temperature shift-down from nonpermissive temperature,40.5°C, to permissive temperature, 36.5°C. Substances which would be absorbed by the human body in daily life were tested as enviromental factors. Reactivation of virus was estimated by observing cells for the cytopathic effect. The factors were divided into the following three classes: Group A: reactivate HSV-2 from latent state, Group B: enhance the reactivation of HSV-2 which was induced by some reactivator, Group C: inhibit the reactivation of HSV-2. From tests so far, some edible dyes such as amaranth and erythrosine were classified as C and nicotine was classified as B. None were classified as A.