Relationship between estrogen receptor thymine-adenine repeat polymorphism and effects of hormone replacement therapy on serum lipid and bone density in postmenopausal women / 대한내과학회지

BACKGROUND: Several biologically plausible mechanisms have been proposed for estrogen-associated changes in lipid and bone metabolism. These effects are thought to be mediated via estrogen receptor (ER). Several polymorphisms in the gene encoding estrogen receptor alpha may modify the effects of hormone replacement therapy on lipid and bone density in postmenopausal women. METHODS: We examined 284 postmenopausal women for thymine-adenine (TA) repeat polymorphism at the ER gene locus and its relationship to lipid and bone density. Their mean age was 52.2+/-5.0 years. We also investigated the association between ER TA repeat polymorphism and changes in lipid and bone density after 3 months and 1 year of hormone replacement therapy. RESULTS: According to the mean number of TA repeats, the women were divided into two groups: group H, with higher number of repeats (TA>16)(n=110); group L, with lower number of repeats (TA

Identification of a mutation in the human raloxifene response element of the transforming growth factor-3 gene

The human transforming growth factor-3 (TGF-3) is an important cytokine to maintain bone mass by inhibiting osteoclast differentiation. Recently raloxifene response element (RRE), a new enhancer with a polypurine sequence for estrogen receptor (ER)-mediated gene activation, was identified on the TGF-3 gene. Functional analysis of the RRE-mediated pathway has shown that this would be an important pathway for bone preserving effect. We found a novel mutation in the RRE sequence by single-strand conformational polymorphism analysis in one of 200 Korean women. Cloning and sequencing revealed a heterozygote in which one allele had an insertion of 20 nucleotides (AGAGAGGGAGAGGGAGA GGG) between nucleotide +71 and +72 and a point mutation at nucleotide +75 (G-A transition), and the other allele had normal sequence. The insertion was a nearly perfect tandem duplication of the wild type DNA sequence. The bone mineral density of the affected woman was not much lower than that of age-matched controls. Transient transfection of the mutant allele showed no significantly different activity compared with that of the wild type allele. These observations suggest that the heterozygote variation of the RRE sequence seems not to be operative in determination of bone mass.

Deflazacort Increases Osteoclast Formation in Mouse Bone Marrow Culture and the Ratio of RANKL/OPG mRNA Expression in Marrow Stromal Cells

Information on precise effects of deflazacort on bone cell function, especially osteoclasts, is quite limited. Therefore, the present study was undertaken to test effects of deflazacort on osteoclast-like cell formation in mouse bone marrow cultures and on the regulation of osteoprotegerin (OPG) and its ligand (RANKL) mRNA expressions by RT-PCR in the ST2 marrow stromal cells. TRAP-positive mononuclear cells increased after the treatment of deflazacort at 10(-9) to 10(-7) M alone for 6 days in a dose-dependent manner. Number of TRAP-positive multi-nucleated cells (MNCs) increased significantly with combined treatment of deflazacort at 10(-7) M and 1,25-(OH)2D3 at 10(-9) M compared to that of cultures treated with 1,25-(OH)2D3 alone (p<0.05). Exposure to deflazacort at 10(-7) M in the presence of 1,25-(OH)2D3 at 10(-9) M in the last 3-day culture had greater stimulatory effect on osteoclast-like cell formation than that of the first 3-day culture did. Deflazacort at 10(-10) -10(-6) M downregulated OPG and upregulated RANKL in mRNA levels in a dose-dependent manner. These observations suggest that deflazacort stimulate osteoclast precursor in the absence of 1,25-(OH)2D3 and enhance differentiation of osteoclasts in the presence of 1,25-(OH)2D3. These effects are, in part, thought to be mediated by the regulation of the expression of OPG and RANKL mRNA in marrow stromal cells.

The Regulation of OPG/OCIF mRNA Epression by IL-1beta in Peripheral Blood Mononuclear Cells / 대한내분비학회지

BACKGROUND: Osteoprotegerin(OPG) is a soluble member of the tumor necrosis factor(TNF) receptor family and inhibits osteoclastogenesis by interrupting the cell-to-cell interaction between osteoblastic/stromal cells and osteoclast progenitors. OPG is expressed in many tissues including osteoblasts and may act on bone tissues in a paracrine and/or autocrine fashion. Futhermore, many cytokines and growth factors are known to influence the regulation of OPG expression in osteoblastic/stromal cells. The aims of the present study were to examine whether or not OPG was expressed in human peripheral blood mononuclear cells(PBMCs) and to investigate the effects of IL-1beta, which were known as potent osteotropic agents, on the regulation of OPG mRNA in PBMCs. METHODS: PBMCs were isolated by centrifugation over Ficoll-Hypaque density gradients from postmenopausal women and cultured in 6-well plates containing alpha-MEM supplemented with 5% FBS. The expression of OPG mRNA in PBMCs was observed by RT-PCR in adherent and nonadherent cells on culture plates. To observe the effect of OPG expression by IL-1beta, we measured the concentration of OPG mRNA by altering the concentration and incubation time of IL-1beta. The measurement of OPG mRNA was done by semi-quantitative PCR and indicated as OPG/GAPDH. RESULTS: OPG was expressed both in cells attached to the surface of culture plates and in non-adherent cells for the incubation of peripheral blood mononuclear cells. The effect of OPG mRNA by IL-1beta tend to increase in accordance with the length of incubation time and maximizes at 12 hours of incubation time and shows 1.2-3.5 times higher than the standard level at the concentration of 0.5ng/ml. However, the increased quantity in concentration varies according to individuals.] CONCLUSION: OPG mRNA is expressed in peripheral blood mononuclear cells and known to be increased by IL-1beta.

Telomerase Activity and Expression of MIB-1 and bcl-2 in Human Chorionic Villi from Early and Term Normal Pregnancy

Telomerase is an enzyme that maintains telomeres and prevents telomere shortening, and may be linked with cellular proliferation or the aging process. The purpose was to examine telomerase activity in human chorionic villi from early and term normal pregnancies, and to analyze the correlation of telomerase activity (TA) with MIB-1 & bcl-2. A total of 37 placentae were obtained from 16 early and 21 term pregnancies. TA was assayed by telomeric repeat amplification protocol, and immunohistochemical staining was performed for MIB-1 & bcl-2 expression. TA & MIB-1 expression were strong in early placenta, but bcl-2 was highly expressed in term placentae. Thirteen (81.25%) of 16 early placentae showed TA, but only 2 (9.52%) of 21 term placentae expressed TA (p<0.01). MIB-1 was observed in nuclei of cytotrophoblast, and the expression rate was 16.09% in early placentae and 2.87% in term placentae (p<0.01). bcl-2 was observed only in the cytoplasm of syncytiotrophoblast. Term placenta demonstrated stronger expression of bcl-2 compared to early placentae (p<0.05). These findings suggest that TA, MIB-1 & bcl-2 expression are critically regulated over the course of gestation: cytotrophoblast, main cells of early chorionic villi, may be a common source of telomerase and proliferative activity. The TA showed good correlation with cellular proliferative activity. Syncytiotrophoblast, may be a main source of bcl-2 expression which is stronger in the term placentae.

A Case of the McCune: Albright Syndrome Associated with Activating Mutations of Stimulatory G Protein / 대한내분비학회지

McCune-Albright syndrome (MAS) is a sporadic disease classically including polyostotic fibrous dysplasia, cafe -au-lait spots, sexual precocity, and other hyperfunctional endocrinopathies. Recent investigations suggest an etiological role for activating embryonic somatic missense mutations in the gene for the a subunit of Gs (Gsa), the G protein that stimulates adenylyl cyclase. DNA from bone, ovary, and blood was analyzed by using polymerase chain reaction and sequenced. A embryological somatic mutation of Gsa gene encoding substitution of a Cys for Arg at amino acid 201 from cells of dysplastic bone and ovary was observed, and the distribution of mutant gene reveals mosaic pattern. We report a case of McCune-Albright syndrome with an activating mutation at codon 201 of Gsa subunit on ovary and bone tissue that was experienced recently.

Telomerase Activity in Human Breast Tumors

BACKGROUND: Telomerase is a ribonucleoprotein enzyme that synthesizes telomeric DNA onto the ends of chromosomes, thereby preventing the replication-dependent shortening of those ends. Telomerase activity is detected in a wide range of cancers of various tissues, and its expression may be a critical step in tumor progression. Our objective was to determine if detection of telomerase activity may be an indicator for diagnosis of breast cancer and if any association exists between telomerase activity and prognostic factors of breast cancer. METHODS: Using a polymerase chain reaction-based telomerase activity assay, we examined telomerase activity in 30 breast cancer specimens (2 ductal carcinoma in situ, 28 invasive ductal carcinoma), 25 benign lesions (14 fibroadenomas, 11 fibrocystic diseases), and 24 normal breast tissues (13 adjacent to malignancy, 11 adjacent to benign lesion). RESULTS: Among surgically resected samples, telomerase activity was detected in 23 (77%) of 30 breast cancers. While telomerase activity was not detected in any of the 11 specimens of fibrocystic disease and the 11 normal tissues adjacent to benign lesion, surprisingly low levels of telomerase activity were detected in 5 (36%) of the 14 fibroadenomas and 1 (7%) of the 13 normal tissues adjacent to malignancy. There was no significant difference in expression of telomerase among prognostic factors of breast cancer. CONCLUSIONS: In summary, telomerase activity may be useful in the diagnosis of breast cancer. We found no correlation between telomerase activity and stage, tumor size, or LN status. Mechanisms of telomerase expression are still under investigation; therefore, the significance of telomerase expression in malignant tumors and their progression remains to be determined.

Telomerase Activity in Human Breast Tumors / 한국유방암학회지

Telomerase is a ribonucleoprotein enzyme that synthesizes telomeric DNA onto the ends of chromosomes. thereby preventing the replication-dependent shortening of these ends. Telomerase activity is detected in a wide range of cancers of various tissues, and its expression may be a critical step in tumor progression. Our objective was to determine if detection of telomerase activity may be an indicator for diagnosis of breast cancer and any association between telomerase activity and prognostic factors of breast cancer. Using a polymerase chain reaction-based telomerase activity assay, we examined telomerase activity in 30 breast cancer specimens (2 ductal carcinoma in situ, 28 invasive ductal carcinoma), 25 benign lesions (14 fibroadenomas, 11 fibrocystic diseases) and 24 normal breast tissues (13 adjacent to malignancy, 11 adjacent to benign lesion). Among surgically resected samples, telomerase activity was detected in 23 (77%) of 30 breast cancers. While telomerase activity was not detected in any of 11 specimens of fibrocystic disease and 11 adjacent normal tissues to benign lesion, surprisingly low levels of telomerase activity were detected in 5 (36%) of 14 fiboadenomas and 1 (7%) of 13 adjacent normal tissues to malignancy. There was no significant difference in expression of telomerase among prognostic factors of breast cancer. In summary, telomerase activity in breast cancer may be useful in diagnosis of breast cancer. We found no correlation between telomerase activity and stage, tumor size or LN status. Mechanisms of telomerase expression are still under investigation; therefore, the significance of telomerase expression in malignant tumors and their progression remains to be determined.

CD5 mRNA Overexpression in Lymphocytes of Allergic Patients / 대한면역학회지

PURPOSE: The CD5 molecules are pan-T cell antigens and are found on a minor subpopulation of B cells. CD5 antigens are involed in an intracellular signal transduction as well as in an intercellular signal transduction between CDS+ T cell/CD72+ B cell by CD5/CD72 interaction. CD5 antigens are known to be participated in classic immune reactions and in this study CDS mRNA expressions by lymphocytes were examined in allergic patients controls, acute febrile infectious disease controls and normal controls to elucidate the possibility of CDS involvement in allergic immune reactions. METHODS: Fifteen allergic patients, ten patients of acute febrile infectious disease patients and ten normal controls were studied. Venous blood was drawn and mononuclear cells were separated. T cells and B cells were separated using immunomagnetic beads. Total RNA was extracted and RT-PCR (reverse transcriptase - polymerase chain reaction) was done to detect CDS antigen mRNA expression. RESULTS: 1) CDS mRNA overexpressions were detected in allergic patient controls as compared to that in acute febrile infectious controls. CDS mRNA was not detected in normal controls. Semiquantitative CD5 mRNA expressions were measured as relative expressions of CD5 to GAPDH. Relative quantities of CD5 mRNA expressions were 90.656.24% in allergic patient controls and 23.76+3.58% in acute febrile infectious patients. CONCLUSIONS: CDS mRNA overexpression is a characteristic phenomenon in allergic immune reactions. From these result, CD5/CD72 pathway might be the preference immune mechanism in allergic immune reaction and the further study for the exact mechanism of CDS involvement in allergic immune reactions may be necessary

Effect of Dexamethasone and Deflazacort on the Function and Gene Expression of the Primary Cultured Human Osteoblast-Like Cells / 대한내분비학회지

Background: Chronic use of glucocorticoid is known to result in osteoporosis. Deflazacort (DFZ), a synthetic glucocorticoid, has been reported to have bone sparing properties in vivo eompared to dexamethasone(DEX). Not only the direct effect of DFZ on human osteoblast but the mechanism by which the drug spares bone remains unclear. This study, therefore, is aimed to investigate the direct effect of DFZ on the proliferation and differentiation of human osteoblast as well as on the gene expression of osteocalcin and osteoblast as well as on the gene expression of osteocalcin and growth factor produced in osteoblast. Methods: Human osteoblast-like cells were cultured from a piece of the tibia removed during selective orthopedic surgery for patients without metabolic bone diseases. The morphological iden- tification of osteoblast-like cell was performed under the light microscope after alkaline phosphatase staining. Cell proliferation rate was determined by [3H] thymidine incorporation into DNA. Cell differentiation was determined by alkaline phophatase activity. mRNA expression was quanti- tatively measured by the competitive reverse transcription-polymerase ehain reaction(RT-PCR). Results: The cultured cells demonstrated 1,25-dihydroxyvitamin D3-induced increases in alkaline phophatase activity and osteocalcin mRNA expression which are the properties of osteoblast. Twenty six percent of the cultured cells were identified as osteoblast-like cells by alkaline phophatase staining. After 24hr incubation with DEX or DFZ, the [3H) thymidine incorporation was significantly inhibited by 100nM DEX or DFL Alkaine phophatase activity was significantly increased by 100nM DEX. Osteocalcin mRNA was significantly decreased by both glueocorticoids. While DEX significantly suppressed expression of asteocalcin mRNA at 10nM and 100nM, DFZ did so only at 100nM. IGF-I mRNA was significantly decreased by 100nM DEX. Conclusion: These results suggest that the inhibitory effect of DFZ on the cell proliferation and protein synthesis is less than that of DEX, which might be responsible for the bone sparing effect of DFZ in vivo.

Loss of heterozygosity on chromosome 10, 13q(Rb), 17p, and p53 gene mutations in human brain gliomas

Using the methods of restriction fragment length polymorphism (RFLP) and single strand conformation polymorphism (SSCP) analyses, we have examined 33 cases of human gliomas with various malignant grades to detect the deletions of putative tumor suppressor gene loci, chromosome 10, 13q(retinoblastoma gene, Rb), 17p, and p53 mutation. We observed loss of heterozygosity (LOH) at loci on chromosome 10 (36%), 13q(Rb) (54%), and 17p(50%) in malignant gliomas. There, however was no allelic loss on chromosome 10 and 17p in low-grade gliomas. Rb gene deletions were seen in low-grade gliomas, including oligodendroglioma and ependymoma. This finding suggests that Rb inactivation may be an early genetic event in the development and progression of gliomas. We correlated the results of LOH on chromosome 17p and p53 mutation. Among the 8 cases which showed LOH on chromosome 17p, only three cases (38%) revealed p53 mutations. Low incidence of p53 mutations in cases with chromosome 17p deletions suggests that some other tumor suppressor genes may be located on chromosome 17p.

Molecular genetic study of primary malignant brain tumors:loss of heterozygosity on chromosome 10, 13q, 17q and 22q / 대한암학회지

No abstract available.

Loss of Heterozygosity on Chromosome 10, 13, 17 and p53 Gene Mutations in Human Brain Gliomas

Gliomas, the most common primary tumors of the human central nervous system, are usually malignant and virtually incurable. They can be classified according to their cellular differentiation:astrocytoma, oligodendroglioma, and ependymoma. The majority of these brain tumors are astrocytomas, which typically progress through three histopathologically defined stages with the passage of time:one premalignant stage, low-grade astrocytoma, and two malignant stages, anaplastic astrocytoma and glioblastoma multiforme. Recent studies on the molecular mechanisms of carcinogensis have demonstrated a possible role for two classes of genes in neoplastic transformation:tumor suppressor genes and oncogenes. Tumor suppressor genes are wild-type alleles of genes that are believed to function normally in the cell to suppress cellular proliferation. Inactivation of both copies of suppressor gene may contribute to neoplastic transformation by removing a normal constraint to cell growth. The well characterised suppressor genes are RB gene and p53 gene. Gliomas, like most other cancers, are associated with several genetic changes, including oncogenes and suppressor genes. In an attempt to further our knowledge of tumor suppressor genes contributing glioma development and progression, restriction fragment length polymorphism(RFLP) analysis was done to determine loss of heterozygosity(LOH) on chromosome 10. 13q(RBI), 17p, and 22q containing putative tumor suppressor genes in 36 cases of human gliomas with various malignancy grades. And to detect p53 gene mutations at exon 5, 6, and 7 in 23 cases of malignant gliomas, polymerase chain reaction-single strand conformation polymorphisms(PCR-SSCP) analysis was performed. Loss of heterozygosity for loci on chromosome 10 were found in four of 5(60%) informative cases of glioblastoma multiforme and one of 2(50%) cases of anaplastic astrocytomas. Loss of heterozygosity on chromosome 17p was found in eight of 17(47%) informative cases of malignant gliomas, including 2 cases of anaplastic oligodendroglioma. There was no allelic loss of chromosome 10 and 17 in benign gliomas. Deletions on RBI locus were seen in six of 10(60%) informative cases of glioblastoma multiforme and two of 5(40%) informative cases of low-grade astrocytomas, suggesting that RBI gene may have a role associated with the early events in tumorigenesis. In PCR-SSCP analysis, six of 23(26%) cases of malignant gliomas, including one case of anaplastic oligodendroglioma, showed mobility shifts on exon 5 or 7 of p53 gene which suggest point mutations of this gene. There was no LOH at IGLC2 locus on chromosome 22. On the basis of the data presented here, it is possible to associate certain molecular abnormalities with gliomas of increasing grades of malignancy, deletion of RB gene, loss of heterozygosity on chromosome 17p, p53 gene mutation, and loss of allele on chromosome 10.

Loss of Heterozygosity on Chromosome 10, 13, 17 and p53 Gene Mutations in Human Brain Gliomas

Gliomas, the most common primary tumors of the human central nervous system, are usually malignant and virtually incurable. They can be classified according to their cellular differentiation:astrocytoma, oligodendroglioma, and ependymoma. The majority of these brain tumors are astrocytomas, which typically progress through three histopathologically defined stages with the passage of time:one premalignant stage, low-grade astrocytoma, and two malignant stages, anaplastic astrocytoma and glioblastoma multiforme. Recent studies on the molecular mechanisms of carcinogensis have demonstrated a possible role for two classes of genes in neoplastic transformation:tumor suppressor genes and oncogenes. Tumor suppressor genes are wild-type alleles of genes that are believed to function normally in the cell to suppress cellular proliferation. Inactivation of both copies of suppressor gene may contribute to neoplastic transformation by removing a normal constraint to cell growth. The well characterised suppressor genes are RB gene and p53 gene. Gliomas, like most other cancers, are associated with several genetic changes, including oncogenes and suppressor genes. In an attempt to further our knowledge of tumor suppressor genes contributing glioma development and progression, restriction fragment length polymorphism(RFLP) analysis was done to determine loss of heterozygosity(LOH) on chromosome 10. 13q(RBI), 17p, and 22q containing putative tumor suppressor genes in 36 cases of human gliomas with various malignancy grades. And to detect p53 gene mutations at exon 5, 6, and 7 in 23 cases of malignant gliomas, polymerase chain reaction-single strand conformation polymorphisms(PCR-SSCP) analysis was performed. Loss of heterozygosity for loci on chromosome 10 were found in four of 5(60%) informative cases of glioblastoma multiforme and one of 2(50%) cases of anaplastic astrocytomas. Loss of heterozygosity on chromosome 17p was found in eight of 17(47%) informative cases of malignant gliomas, including 2 cases of anaplastic oligodendroglioma. There was no allelic loss of chromosome 10 and 17 in benign gliomas. Deletions on RBI locus were seen in six of 10(60%) informative cases of glioblastoma multiforme and two of 5(40%) informative cases of low-grade astrocytomas, suggesting that RBI gene may have a role associated with the early events in tumorigenesis. In PCR-SSCP analysis, six of 23(26%) cases of malignant gliomas, including one case of anaplastic oligodendroglioma, showed mobility shifts on exon 5 or 7 of p53 gene which suggest point mutations of this gene. There was no LOH at IGLC2 locus on chromosome 22. On the basis of the data presented here, it is possible to associate certain molecular abnormalities with gliomas of increasing grades of malignancy, deletion of RB gene, loss of heterozygosity on chromosome 17p, p53 gene mutation, and loss of allele on chromosome 10.

A case of squamous cell carcinoma arising in benign cystic teratoma of the ovary / 대한산부인과학회잡지

No abstract available.

A case of gastroschisis associated with fetal death in utero, and ultrasonographic findings which were in antenatal period / 대한산부인과학회잡지

No abstract available.