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Tomohiko Urano

Publications and source records attributed to Tomohiko Urano.

At least 19 recordsLinked to original sources
PubMed2007

Q89R polymorphism in the LDL receptor-related protein 5 gene is associated with spinal osteoarthritis in postmenopausal Japanese women.

STUDY DESIGN: An association study investigating the genetic etiology for spinal osteoarthritis. OBJECTIVE: To determine the association of single-nucleotide polymorphism (SNP) causing an amino-acid change (Q89R) in the low-density lipoprotein receptor-related protein 5 (LRP5) coding region with spinal osteoarthritis. SUMMARY OF BACKGROUND DATA: Wnt/beta-catenin signaling pathway regulates bone density through a Wnt coreceptor LRP5. This pathway is also involved in cartilage development and homeostasis, suggesting that genetic variation in LRP5 gene may affect the pathogenesis of cartilage-related diseases, such as osteoarthritis. METHODS: We evaluated the presence of osteophytes, endplate sclerosis, and narrowing of disc spaces in 357 Japanese postmenopausal women. Missense coding SNP for Q89R of LRP5 gene was determined using TaqMan polymerase chain reaction (PCR) method. RESULTS: We found that subjects without the R allele (QQ; n = 321) had a significantly lower osteophyte formation score than did subjects bearing at least one R allele (QR + RR; n = 36) (7.80 vs. 10.89, P = 0.0019 by analysis of covariance). CONCLUSIONS: We suggest that a genetic variation at the LRP5 gene locus is associated with spinal osteoarthritis, in line with the involvement of the LRP5 gene in the bone and cartilage metabolism.

Aged↗
PubMed2006

alpha-Synuclein stimulates differentiation of osteosarcoma cells: relevance to down-regulation of proteasome activity.

Because a limited study previously showed that alpha-synuclein (alpha-syn), the major pathogenic protein for Parkinson disease, was expressed in differentiating brain tumors as well as various peripheral cancers, the main objective of the present study was to determine whether alpha-syn might be involved in the regulation of tumor differentiation. For this purpose, alpha-syn and its non-amyloidogenic homologue beta-syn were stably transfected to human osteosarcoma MG63 cell line. Compared with beta-syn-overexpressing and vector-transfected cells, alpha-syn-overexpressing cells exhibited distinct features of differentiated osteoblastic phenotype, as shown by up-regulation of alkaline phosphatase and osteocalcin as well as inductive matrix mineralization. Further studies revealed that proteasome activity was significantly decreased in alpha-syn-overexpressing cells compared with other cell types, consistent with the fact that proteasome inhibitors stimulate differentiation of various osteoblastic cells. In alpha-syn-overexpressing cells, protein kinase C (PKC) activity was significantly decreased, and reactivation of PKC by phorbol ester significantly restored the proteasome activity and abrogated cellular differentiation. Moreover, activity of lysosome was up-regulated in alpha-syn-overexpressing cells, and treatment of these cells with autophagy-lysosomal inhibitors resulted in a decrease of proteasome activity associated with up-regulation of alpha-syn expression, leading to enhance cellular differentiation. Taken together, these results suggest that the stimulatory effect of alpha-syn on tumor differentiation may be attributed to down-regulation of proteasome, which is further modulated by alterations of various factors, such as protein kinase C signaling pathway and a autophagy-lysosomal degradation system. Thus, the mechanism of alpha-syn regulation of tumor differentiation and neuropathological effects of alpha-syn may considerably overlap with each other.

Autophagy↗
PubMed2006

A ubiquitin E3 ligase Efp is up-regulated by interferons and conjugated with ISG15.

Interferon (IFN) regulates various target genes that mediate important roles in immune responses such as antiviral state. Protein ISG15-conjugation (ISGylation) is implicated in the IFN-induced antiviral response. Here we demonstrate that Efp mRNA as well as protein expression could be up-regulated by Type I IFN in HeLa cells and HepG2 cells. Luciferase assay reveals that the first intron of Efp gene contains a functional interferon-stimulated response element (ISRE) and electrophoretic mobility shift assay shows that the ISRE binds to signal transducer and activator of transcription 1 (STAT1). Chromatin immunoprecipitation assays have shown that the ISRE recruits STAT1 in vivo IFN-dependently. Moreover, we demonstrate that Efp protein could be conjugated with not only ubiquitin but also ISG15. These data suggest that Efp is an IFN-responsive gene that potentially mediates IFN actions, involved in ISGylation and ubiquitination of proteins including Efp itself.

Cell Line, Tumor↗
PubMed2006

[Wnt-beta-catenin signaling in bone metabolism].

The Wnt-beta-catenin signaling pathway is involved in cell proliferation, differentiation and morphogenesis. Recently, mutations of the low-density lipoprotein receptor-related protein 5 (LRP5 ) gene, a receptor of this signaling, have been described to be associated with both osteoporosis-pseudoglioma syndrome and the high bone mass phenotype. It was found that the loss of function of the LRP5 in both human and mice yielded a decrease in bone formation, and an active mutation in this same gene resulted in a high bone mass trait. Moreover, several groups and we reported that single nucleotide polymorphisms in the LRP5 gene predicted the bone mass. This pathway also affects the pathogenesis of osteoarthritis and multiple myeloma. These findings indicate that Wnt-beta-catenin signaling pathway plays important roles in the skeletal biology.

Animals↗
PubMed2005

Estrogen-responsive finger protein as a new potential biomarker for breast cancer.

PURPOSE: Estrogen-responsive finger protein (Efp) is a member of RING finger-B box-Coiled Coil family and is also a downstream target of estrogen receptor alpha. Previously, Efp was shown to mediate estrogen-induced cell growth, which suggests possible involvement in the development of human breast carcinomas. In this study, we examined expression of Efp in breast carcinoma tissues and correlated these findings with various clinicopathologic variables. EXPERIMENTAL DESIGN: Thirty frozen specimens of breast carcinomas were used for immunohistochemistry and laser capture microdissection/real-time PCR of Efp. Immunohistochemistry for Efp was also done in 151 breast carcinoma specimens fixed with formalin and embedded in paraffin wax. RESULTS: Efp immunoreactivity was detected in breast carcinoma cells and was significantly associated with the mRNA level (n = 30). Efp immunoreactivity was positively associated with lymph node status or estrogen receptor alpha status and negatively correlated with histologic grade or 14-3-3sigma immunoreactivity (n = 151). Moreover, Efp immunoreactivity was significantly correlated with poor prognosis of breast cancer patients, and multivariate analyses of disease-free survival and overall survival for 151 breast cancer patients showed that Efp immunoreactivity was the independent marker. CONCLUSIONS: Our data suggest that Efp immunoreactivity is a significant prognostic factor in breast cancer patients. These findings may account for an oncogenic role of Efp in the tumor progression of breast carcinoma.

14-3-3 Proteins↗
PubMed2005

Estrogen receptor-binding fragment-associated antigen 9 is a tumor-promoting and prognostic factor for renal cell carcinoma.

The estrogen receptor-binding fragment-associated antigen 9 (EBAG9) has been identified as a primary estrogen-responsive gene in human breast cancer MCF7 cells. A high expression of EBAG9 has been observed in invasive breast cancer and advanced prostate cancer, suggesting a tumor-promoting role of the protein in malignancies. Here we show that intratumoral (i.t.) administration of small interfering RNA against EBAG9 exerted overt regression of tumors following s.c. implantation of murine renal cell carcinoma (RCC) Renca cells. Overexpression of EBAG9 did not promote the proliferation of culture Renca cells; however, the inoculated Renca cells harboring EBAG9 (Renca-EBAG9) in BALB/c mice grew faster and developed larger tumors compared with Renca cells expressing vector alone (Renca-vector). After renal subcapsular implantation, Renca-EBAG9 tumors significantly enlarged compared with Renca-vector tumors in BALB/c mice, whereas both Renca-EBAG9 and Renca-vector tumors were developed with similar volumes in BALB/c nude mice. No apparent difference was observed in specific cytotoxic T-cell responses against Renca-EBAG9 and Renca-vector cells; nonetheless, the number of infiltrating CD8+ T lymphocytes was decreased in Renca-EBAG9 subcapsular tumors. Furthermore, immunohistochemical study of EBAG9 in 78 human RCC specimens showed that intense and diffuse cytoplasmic immunostaining was observed in 87% of the cases and positive EBAG9 immunoreactivity was closely correlated with poor prognosis of the patients. Multivariate analysis revealed that high EBAG9 expression was an independent prognostic predictor for disease-specific survival (P = 0.0485). Our results suggest that EBAG9 is a crucial regulator of tumor progression and a potential prognostic marker for RCC.

Adult↗
PubMed2005

Association of a single nucleotide polymorphism in the lipoxygenase ALOX15 5'-flanking region (-5229G/A) with bone mineral density.

The 12/15-lipoxygenase gene Alox15 has been identified as a susceptibility gene for bone mineral density (BMD) in mice through combined genetic and genomic analyses. Here we studied the association between bone mineral density and an ALOX15 gene single nucleotide polymorphism to assess the potential involvement of the human ALOX15 gene in postmenopausal osteoporosis. Specifically, we examined the association between a single nucleotide polymorphism at -5299G/A in the ALOX15 5'-flanking region with BMD in 319 postmenopausal Japanese women (66.7 +/- 8.9 years, mean +/- SD). We found that subjects bearing at least one variant A allele (GA + AA; n = 273) had significantly lower Z scores for lumbar spine and total body bone mineral density than did subjects with no A allele (GG; n = 46) (lumbar spine, -0.25 +/- 1.34 versus 0.48 +/- 1.70; P = 0.0014; total body, 0.25 +/- 1.01 vs 0.62 +/- 1.11; P = 0.048). These findings suggest that the ALOX15 gene is one of the genetic determinants of BMD in postmenopausal women. Accordingly, this polymorphism could be useful as a genetic marker for predicting the risk of osteoporosis.

Aged↗
PubMed2005

[Effects of estrogen and selective estrogen receptor modulators on osteoporosis].

Evidence indicates that estrogen and raloxifene hydrochloride, a selective estrogen receptor modulator, prevent bone loss and reduce the risk of bone fractures in postmenopausal women. However, recent reports indicate that the health risks associated with the use of estrogen, which include breast cancer and coronary heart disease (CHD), exceed the benefits. In contrast, raloxifene is associated with a lower incidence of breast cancer and is not associated with CHD. Therefore, the use of raloxifene is preferable for the prevention and treatment of osteoporosis in postmenopausal patients.

Breast Neoplasms↗
PubMed2004

14-3-3sigma is down-regulated in human prostate cancer.

The 14-3-3sigma is a negative regulator of the cell cycle, which is induced by p53 in response to DNA damage. It has been characterized as an epithelium-specific marker and down-regulation of the protein has been shown in breast cancers, suggesting its tumor-suppressive activity in epithelial cells. Here we demonstrate that 14-3-3sigma protein is down-regulated in human prostate cancer cell lines, LNCaP, PC3, and DU145 compared with normal prostate epithelial cells. Immunohistochemical analysis of primary prostate cells shows that the expression of 14-3-3sigma protein is epithelial cell-specific. Among prostate pathological specimens, > 95% of benign hyperplasia samples show significant and diffuse immunostaining of 14-3-3sigma in the cytoplasm whereas < 20% of carcinoma samples show positive staining. In terms of mechanisms for the down-regulation of 14-3-3sigma in prostate cancer cells, hypermethylation of the gene promoter plays a causal role in LNCaP cells as 14-3-3sigma mRNA level was elevated by 5-aza-2'-deoxycytidine demethylating treatment. Intriguingly, the proteasome-mediated proteolysis is responsible for 14-3-3sigma reduction in DU145 and PC3 cells, as 14-3-3sigma protein expression was increased by treatment with a proteasome inhibitor MG132. Furthermore, tumor necrosis factor-related apoptosis-inducing ligand enhances 14-3-3sigma gene and protein expression in DU145 and PC3 cells. These data suggest that 14-3-3sigma expression is down-regulated during the neoplastic transition of prostate epithelial cells.

14-3-3 Proteins↗
PubMed2004

Association of a single-nucleotide polymorphism in low-density lipoprotein receptor-related protein 5 gene with bone mineral density.

Low-density lipoprotein receptor-related protein 5 (LRP5) is an important regulator of osteoblast growth and differentiation, affecting peak bone mass in vertebrates. Here, we analyzed whether the LRP5 gene was involved in the etiology of postmenopausal osteoporosis, using association analysis between bone mineral density (BMD) and an LRP5 gene single-nucleotide polymorphism (SNP). Association of an SNP in the LRP5 gene at IVS17-1677C > A (intron 17) with BMD was examined in 308 postmenopausal Japanese women (65.2 +/- 9.6 years; mean +/- SD). The subjects bearing at least one variant A allele (CA + AA; n = 142) had significantly lower Z scores for total body and lumbar BMD than the subjects with no A allele (CC; n = 166) (total body, 0.08 +/- 1.09 versus 0.50 +/- 1.03; P = 0.0022; lumbar spine, -0.42 +/- 1.43 versus -0.02 +/- 1.42; P = 0.013). These findings suggest that the LRP5 gene is a candidate for the genetic determinants of BMD in postmenopausal women, and this SNP could be useful as a genetic marker for predicting the risk of osteoporosis.

Aged↗
PubMed2004

[TGF-beta].

Explore the source record for details and available documents.

Animals↗
PubMed2003

EBAG9/RCAS1 expression and its prognostic significance in prostatic cancer.

Estrogen receptor-binding fragment-associated gene 9 (EBAG9) has been identified as a primary estrogen-responsive gene from MCF-7 human breast cancer cells (Watanabe T, et al., Mol Cell Biol 1998;18:442-9). EBAG9 is identical with RCAS1 (receptor-binding cancer antigen expressed on SiSo cells), which has been reported as a cancer cell surface antigen implicated in immune escape (Nakashima M, et al., Nat Med 1999;5:938-42). In our present study, we examined EBAG9 expression in human prostatic tissues and investigated its prognostic significance in patients with prostatic cancer. EBAG9 expression in normal prostatic epithelial cells and PC-3, DU145 and LNCaP cancer cells was determined by Western blot analysis. Immunohistochemic analysis was performed in 21 benign and 81 malignant prostatic specimens, and patients' charts were reviewed for clinical, pathologic and survival data. EBAG9 was abundantly expressed in the prostate cancer cells compared to the normal epithelial cells. Strong and diffuse immunostaining in the cytoplasm of EBAG9 was found in 44 of 81 (54%) cancerous tissue samples. EBAG9 expression significantly correlated with advanced pathologic stages and high Gleason score (p = 0.0305 and < 0.0001, respectively). EBAG9 was more frequently expressed at sites of capsular penetration (79%) and lymph node metastasis (100%) compared to intracapsular primary tumors (54%) (p = 0.0264 and 0.0048, respectively). Positive EBAG9 immunoreactivity significantly correlated with poor PSA failure-free survival (p = 0.0059). EBAG9/RCAS1 may play a significant role in cancer progression via an immune escape system. Immunodetection of EBAG9/RCAS1 expression can be a negative prognostic indicator for patients with prostatic cancer.

Aged↗
PubMed2003

Estrogen-responsive RING finger protein controls breast cancer growth.

Most of the breast cancers initially respond to endocrine therapy that reduces the levels of estrogens or competes with estrogen for binding to its receptor. Most of the patients, however, acquire resistance to endocrine therapy with tamoxifen and aromatase inhibitors later. We assumed that identification of estrogen-responsive genes those regulate the growth of breast cancer is indispensable to develop new strategies targeting the genes and overcome the resistance to current endocrine therapy. Estrogen-responsive finger protein (Efp) is one of the estrogen receptor (ER)-target genes we have cloned using genomic binding site cloning. Efp features a structure of the RING-finger B-box coiled-coil (RBCC) motif. We postulated that Efp is a critical factor in proliferation of breast tumors. In a model system using MCF7 cells grown in xenografts, we showed that inhibition of Efp expression by antisense oligonucleotide reduced the tumor growth. MCF7 cells overexpressing Efp formed tumors in xenografts even in estrogen deprivation environment. By yeast two-hybrid screen, we identified that Efp interacts with 14-3-3sigma, which is known as a cell cycle brake that causes G2 arrest and expressed in normal mammary glands. In vitro studies have revealed that Efp functions as a ubiquitin-protein ligase (E3) that targets 14-3-3sigma. These data suggest that Efp controls breast cancer growth through ubiquitin-dependent proteolysis of 14-3-3sigma. Future studies may provide a new therapy to block breast tumor proliferation by targeting Efp.

14-3-3 Proteins↗
PubMed2003

[Bone metabolism in estrogen receptor-deficient mice].

Mouse models have been established with a deficiency of ERalpha, ERbeta, or both to elucidate the function of estradiol in bone metabolism. This review focuses on data accumulated from studies of estrogen receptor-deficient mice.

English Abstract↗