Simian virus 40-transformed human ovarian surface epithelial cells escape normal growth controls but retain morphogenetic responses to extracellular matrix

X-linked hypophosphatemia (XLH) is caused by inactivating mutations of PEX, an endopeptidase of uncertain function. This defect is shared by Hyp mice, the murine homologue of the human disease, in which a 3′ Pex deletion has been documented. In the present study, we report that immortalized osteoblasts derived from the simian virus 40 (SV40) transgenic Hyp mouse (TMOb- Hyp) have an impaired capacity to mineralize extracellular matrix in vitro. Compared with immortalized osteoblasts from the SV40 transgenic normal mouse (TMOb-Nl), osteoblast cultures from the SV40 Hyp mouse exhibit diminished 45Ca accumulation into extracellular matrix (37 ± 6 vs. 1,484 ± 68 counts ⋅ min−1 ⋅ μg protein−1) and reduced formation of mineralization nodules. Moreover, in coculture experiments, we found evidence that osteoblasts from the SV40 Hyp mouse produce a diffusible factor that blocks mineralization of extracellular matrix in normal osteoblasts. Our findings indicate that abnormal PEX in osteoblasts is associated with the accumulation of a factor(s) that inhibits mineralization of extracellular matrix in vitro.

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Microenvironmental Regulation of BRCA1 Gene Expression by c-Jun and Fra2 in Premalignant Human Ovarian Surface Epithelial Cells

Molecular Cancer Research ◽

10.1158/1541-7786.mcr-12-0395 ◽

2013 ◽

Vol 11 (3) ◽

pp. 272-281 ◽

Cited By ~ 9

Author(s):

Lixin Zhou ◽

Marcia Graves ◽

Gwen MacDonald ◽

Jane Cipollone ◽

Christopher R. Mueller ◽

...

Keyword(s):

Gene Expression ◽

Epithelial Cells ◽

Brca1 Gene ◽

Ovarian Surface ◽

Ovarian Surface Epithelial

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The 5'-flanking region of the mouse thymidylate synthase gene is necessary but not sufficient for normal regulation in growth-stimulated cells

Molecular and Cellular Biology ◽

10.1128/mcb.11.2.1023-1029.1991 ◽

1991 ◽

Vol 11 (2) ◽

pp. 1023-1029

Author(s):

Y Li ◽

D Li ◽

K Osborn ◽

L F Johnson

Keyword(s):

Thymidylate Synthase ◽

Cultured Cells ◽

Transcriptional Start Site ◽

Simian Virus 40 ◽

Normal Growth ◽

Housekeeping Gene ◽

Simian Virus ◽

Coding Region ◽

Proliferating Cells ◽

Early Promoter

The thymidylate synthase (TS) gene is a housekeeping gene that is expressed at much higher levels in proliferating cells than in quiescent cells. We have studied the role of the TS 5'-flanking sequences in regulating the level of expression of the mouse TS gene. A variety of chimeric TS minigenes that contain different promoters linked either to the TS coding region (with or without introns) or to the chloramphenicol acetyltransferase (CAT) coding region were constructed. The activities of the minigenes were determined by transfecting them into cultured cells and measuring the levels of mRNA or enzyme derived from the chimeric genes. We found that the mouse TS promoter had about the same strength as the simian virus 40 early promoter but was significantly stronger than the herpes simplex virus thymidine kinase promoter. Stable transfection studies revealed that minigenes consisting of the normal TS promoter (extending to -1 kb), coding region, and polyadenylation signal were regulated normally in response to growth stimulation. When the TS promoter was replaced by the simian virus 40 early promoter or by a TS promoter that retained only 60 nucleotides upstream of the first transcriptional start site, the minigene was expressed constitutively. A minigene consisting of the TS promoter (extending to -1 kb) linked to the CAT coding region was also expressed constitutively. These observations indicate that sequences upstream of the transcriptional start sites of the TS gene are necessary, although not sufficient, for normal growth-regulated expression of the mouse TS gene.

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Nonrandom chromosomal imbalances in human ovarian surface epithelial cells immortalized by HPV16-E6E7 viral oncogenes

Cancer Genetics and Cytogenetics ◽

10.1016/s0165-4608(01)00473-3 ◽

2001 ◽

Vol 130 (2) ◽

pp. 141-149 ◽

Cited By ~ 23

Author(s):

Sai Wah Tsao ◽

Natalie Wong ◽

Xianghong Wang ◽

Yu Liu ◽

Thomas Shek Kong Wan ◽

...

Keyword(s):

Epithelial Cells ◽

Chromosomal Imbalances ◽

Viral Oncogenes ◽

Ovarian Surface ◽

Ovarian Surface Epithelial

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Strontium phosphate transfection of human cells in primary culture: stable expression of the simian virus 40 large-T-antigen gene in primary human bronchial epithelial cells

Molecular and Cellular Biology ◽

10.1128/mcb.7.5.2031-2034.1987 ◽

1987 ◽

Vol 7 (5) ◽

pp. 2031-2034

Author(s):

D E Brash ◽

R R Reddel ◽

M Quanrud ◽

K Yang ◽

M P Farrell ◽

...

Keyword(s):

Epithelial Cells ◽

Primary Culture ◽

Simian Virus 40 ◽

Simian Virus ◽

T Antigen ◽

Bronchial Epithelial Cells ◽

Large T Antigen ◽

Bronchial Epithelial ◽

Antigen Gene ◽

Strontium Phosphate

Strontium ion formed DNA-phosphate precipitates analogous to those formed by calcium but lacking the lethal and differentiation-inducing effects of calcium on many epithelial cell types in primary culture. Human primary bronchial epithelial cells were transiently and stably transfected by using strontium phosphate; the frequency of stable transformation with a plasmid carrying the simian virus 40 large-T-antigen gene was greater than 10(-4).

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