Two distinct osteoblast-specific cis-acting elements control expression of a mouse osteocalcin gene.

Osteoblasts are cells of mesodermal origin that play a pivotal role during bone growth and mineralization. The mechanisms governing osteoblast-specific gene expression are still unknown. To understand these mechanisms, we analyzed the cis-acting elements of mouse osteocalcin gene 2 (mOG2), the best-characterized osteoblast-specific gene, by DNA transfection experiments in osteoblastic and nonosteoblastic cell lines and by DNA-binding assays. 5' deletion analysis of an mOG2 promoter-luciferase chimeric gene showed that a region located between -147 and -34 contained most if not all of the regulatory elements required for osteoblast-specific expression. Three different binding sites, called A, B, and C, for factors present in nuclear extracts of osteoblasts were identified in this short promoter by DNase I footprint assays. In gel retardation assays, the A element, located between bp -64 and -47, bound a factor present only in nuclear extracts of osteoblastic cell lines and nonmineralizing primary osteoblasts. The B element, located between bp -110 and -83, bound a ubiquitously expressed factor. The C element, located between bp -146 and -132, bound a factor present only in nuclear extracts of osteoblastic cell lines and nonmineralizing and mineralizing primary osteoblasts. When cloned upstream of a minimum osteocalcin promoter or a heterologous promoter, multimers of the A element strongly increased the activities of these promoters in osteoblastic cell lines at two different stages of differentiation but in no other cell line; we named this element osteocalcin-specific element 1 (OSE1). Multimers of the C element increased the activities of these promoters predominantly in a differentiated osteoblastic cell line; we named this element OSE2. This study demonstrates that two distinct cis-acting elements are responsible for osteoblast expression of mOG2 and provides for the first time a functional characterization of osteoblast-specific cis-acting elements. We speculate that these two elements may be important at several stages of osteoblast differentiation.

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MicroRNA-133a Inhibits Osteosarcoma Cells Proliferation and Invasion via Targeting IGF-1R

Cellular Physiology and Biochemistry ◽

10.1159/000438653 ◽

2016 ◽

Vol 38 (2) ◽

pp. 598-608 ◽

Cited By ~ 32

Author(s):

Guangnan Chen ◽

Tingting Fang ◽

Zhongming Huang ◽

Yiying Qi ◽

Shaohua Du ◽

...

Keyword(s):

Cell Line ◽

Cell Lines ◽

Luciferase Reporter ◽

Osteoblastic Cell ◽

Osteosarcoma Cell ◽

Osteosarcoma Cells ◽

Invasion And Metastasis ◽

Osteoblastic Cell Line ◽

Human Osteosarcoma ◽

Human Osteosarcoma Cell

Background/Aims: MicroRNAs (miRNAs) are a class of small noncoding RNAs that regulate gene expression by repressing translation or cleaving RNA transcripts in a sequence-specific manner. Downregulated microRNAs and their roles in cancer development have attracted much attention. A growing body of evidence showed that microRNA-133a (miR-133a) has inhibitory effects on cell proliferation, migration, invasion, and metastasis of osteosarcoma. Methods: MiR-133a expression in human osteosarcoma cell lines and human normal osteoblastic cell line hFOB was investigated by real-time PCR (RT-PCR). The role of miR-133a in human osteosarcoma growth and invasion was assessed in cell lines in vitro and in vivo. Then, luciferase reporter assay validated IGF-1R as a downstream and functional target of miR-133a, and functional studies revealed that the anti-tumor effect of miR-133a was probably due to targeting and repressing of IGF-1R expression. Results: MiR-133a was lower expressed in human osteosarcoma cell lines than human normal osteoblastic cell line hFOB and its effect on inhibiting proliferation, invasion and metastasis is mediated by its direct interaction with the IGF-1R. Furthermore, the tumour-suppressive function of miR-133a probably contributed to inhibiting the activation AKT and ERK signaling pathway. Conclusion: MiR-133a suppresses osteosarcoma progression and metastasis by targeting IGF-1R in human osteosarcoma cells, providing a novel candidate prognostic factor and a potential anti-metastasis therapeutic target in osteosarcoma.

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Genes Regulated in Metastatic Osteosarcoma: Evaluation by Microarray Analysis in Four Human and Two Mouse Cell Line Systems

Sarcoma ◽

10.1155/2012/937506 ◽

2012 ◽

Vol 2012 ◽

pp. 1-13 ◽

Cited By ~ 19

Author(s):

Roman Muff ◽

Ram Mohan Ram Kumar ◽

Sander M. Botter ◽

Walter Born ◽

Bruno Fuchs

Keyword(s):

Gene Expression ◽

Cell Line ◽

Cell Lines ◽

Expression Profiles ◽

Treatment Strategies ◽

Metastatic Potential ◽

New Drugs ◽

Differentially Expressed ◽

Osteoblastic Cell ◽

Osteoblastic Cell Line

Osteosarcoma (OS) is a rare bone neoplasm that affects mainly adolescents. It is associated with poor prognosis in case of metastases formation. The search for metastasis predicting markers is therefore imperative to optimize treatment strategies for patients at risk and important for the search of new drugs for the treatment of this devastating disease. Here, we have analyzed by microarray the differential gene expression in four human and two mouse OS cell line systems consisting of parental cell lines with low metastatic potential and derivatives thereof with increased metastatic potential. Using two osteoblastic cell line systems, the most common OS phenotype, we have identified forty-eight common genes that are differentially expressed in metastatic cell lines compared to parental cells. The identified subset of metastasis relevant genes in osteoblastic OS overlapped only minimally with differentially expressed genes in the other four preosteoblast or nonosteoblastic cell line systems. The results imply an OS phenotype specific expression pattern of metastasis regulating proteins and form a basis for further investigation of gene expression profiles in patients’ samples combined with survival analysis with the aim to optimize treatment strategies to develop new drugs and to consequently improve the survival of patients with the most common form of osteoblastic OS.

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Subcloning of three osteoblastic cell lines with distinct differentiation phenotypes from the mouse osteoblastic cell line KS-4

Bone ◽

10.1016/s8756-3282(96)00255-4 ◽

1996 ◽

Vol 19 (5) ◽

pp. 429-436 ◽

Cited By ~ 29

Author(s):

T. Yamashita ◽

H. Ishii ◽

K. Shimoda ◽

T.K. Sampath ◽

T. Katagiri ◽

...

Keyword(s):

Cell Line ◽

Cell Lines ◽

Osteoblastic Cell ◽

Osteoblastic Cell Line

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Elevated Expression of the Testis-specific Gene WBP2NL in Breast Cancer

Biomarkers in Cancer ◽

10.4137/bic.s19079 ◽

2015 ◽

Vol 7 ◽

pp. BIC.S19079 ◽

Cited By ~ 5

Author(s):

Seyedmehdi Nourashrafeddin ◽

Mehdi Dianatpour ◽

Mahmoud Aarabi ◽

Maryam Beigom Mobasheri ◽

Golnesa Kazemi-oula ◽

...

Keyword(s):

Breast Cancer ◽

Cell Line ◽

Cell Lines ◽

Specific Gene ◽

Rt Pcr ◽

Noncancerous Tissue ◽

Ww Domain ◽

Group I ◽

Elevated Expression ◽

Cancer Tissues

Breast cancer is one of the most common causes of cancer death in women; therefore, the study of molecular aspects of breast cancer for finding new biomarkers is important. Recent studies have shown that WW domain-binding protein 2 (WBP2) is important for the oncogenic property of breast cancer. WWP2 N-terminal-like ( WBP2NL) is a testis-specific signaling protein that induces meiotic resumption and oocyte activation events. Our previous study revealed that WBP2NL gene expression is elevated in actively dividing cells and it might be associated with cellular proliferation and tumorigenic process. However, the clinical relevance and importance of WBP2NL gene in cancer has not been understood yet. Therefore, we were interested in analyzing the expression of WBP2NL gene in human breast cancer tissues and breast cancer cell lines, for the first time. We used reverse transcription-polymerase chain reaction (RT-PCR) and semi-nested RT-PCR to evaluate the expression of WBP2NL in malignant breast cancer and adjacent noncancerous tissue (ANCT) samples, as well as MCF-7 and MDA-MB-231 cell lines. The WBP2NL gene was expressed in 45 out of 50 (90%) breast cancer tissues and overexpressed in the MDA-MB-231 cell line. We suggest that WBP2NL may play roles in breast cancer activation maybe through binding to a group I WW domain protein. The elevated expression of WBP2NL gene in breast cancer and MDA-MB-231 cell line leads us to suggest that WBP2NL might be considered as a novel prognostic factor for early diagnosis of breast cancer.

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Prostaglandin E receptor subtypes in mouse osteoblastic cell line.

Endocrinology ◽

10.1210/endo.137.5.8612504 ◽

1996 ◽

Vol 137 (5) ◽

pp. 1698-1705 ◽

Cited By ~ 46

Author(s):

M Suda ◽

K Tanaka ◽

K Natsui ◽

T Usui ◽

I Tanaka ◽

...

Keyword(s):

Cell Line ◽

Osteoblastic Cell ◽

Prostaglandin E ◽

Receptor Subtypes ◽

Osteoblastic Cell Line

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Stimulative Effects of (22E,24R)-Ergosta-7,22-diene-3β,5α,6β-triol from Fruiting Bodies of Tricholoma auratum, on a Mouse Osteoblastic Cell Line, MC3T3-E1

Biological and Pharmaceutical Bulletin ◽

10.1248/bpb.25.1040 ◽

2002 ◽

Vol 25 (8) ◽

pp. 1040-1044 ◽

Cited By ~ 11

Author(s):

Keishi Hata ◽

Fuyuki Sugawara ◽

Naganori Ohisa ◽

Saori Takahashi ◽

Kazuyuki Hori

Keyword(s):

Cell Line ◽

Osteoblastic Cell ◽

Fruiting Bodies ◽

Osteoblastic Cell Line

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Analysis of a tissue-specific enhancer: ARF6 regulates adipogenic gene expression

Molecular and Cellular Biology ◽

10.1128/mcb.12.3.1202-1208.1992 ◽

1992 ◽

Vol 12 (3) ◽

pp. 1202-1208

Author(s):

R A Graves ◽

P Tontonoz ◽

B M Spiegelman

Keyword(s):

Gene Expression ◽

Cultured Cells ◽

Mutational Analysis ◽

Cell Types ◽

Specific Gene ◽

Enhancer Activity ◽

Cis Acting ◽

Specific Gene Expression ◽

Nuclear Extracts ◽

Adipogenic Gene

The molecular basis of adipocyte-specific gene expression is not well understood. We have previously identified a 518-bp enhancer from the adipocyte P2 gene that stimulates adipose-specific gene expression in both cultured cells and transgenic mice. In this analysis of the enhancer, we have defined and characterized a 122-bp DNA fragment that directs differentiation-dependent gene expression in cultured preadipocytes and adipocytes. Several cis-acting elements have been identified and shown by mutational analysis to be important for full enhancer activity. One pair of sequences, ARE2 and ARE4, binds a nuclear factor (ARF2) present in extracts derived from many cell types. Multiple copies of these elements stimulate gene expression from a minimal promoter in preadipocytes, adipocytes, and several other cultured cell lines. A second pair of elements, ARE6 and ARE7, binds a separate factor (ARF6) that is detected only in nuclear extracts derived from adipocytes. The ability of multimers of ARE6 or ARE7 to stimulate promoter activity is strictly adipocyte specific. Mutations in the ARE6 sequence greatly reduce the activity of the 518-bp enhancer. These data demonstrate that several cis- and trans-acting components contribute to the activity of the adipocyte P2 enhancer and suggest that ARF6, a novel differentiation-dependent factor, may be a key regulator of adipogenic gene expression.

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