Abstract

To examine the p53 protein expressed in human mammary epithelial cell strains grown in vitro we first established the presence of only wild-type p53 and lack of any missense mutations in a representative normal mammary epithelial cell strain, 76N, by cloning and sequencing the entire coding region of the p53 mRNA. The p53 protein expressed in this cell strain and a number of similarly derived normal mammary epithelial cell strains was compared with mammary epithelial tumor cell lines having known p53 mutations and with fibroblasts derived from normal mammary tissue. In all cell strains, immunoprecipitation from metabolically labelled cells using monoclonal antibodies (mAb) PAb 1801 and PAb 122 revealed easily detectable p53 protein. Surprisingly, mAb PAb 1620 (wild type-specific) and PAb 240 (mutant-specific) each immunoprecipitated p53 protein from both normal and tumor cells. Furthermore, p53 protein in normal mammary epithelial cells was shown to be markedly more stable (half-life of ∼3 h) compared to that in mammary fibroblasts or rodent fibroblasts (half-life < 30 min). Immunocytochemistry with PAb 1801 showed detectable p53 protein in normal mammary epithelial cells with a predominantly nuclear staining; however, p53 protein was undetectable in fibroblasts by immunocytochemistry. Together, these results reveal unusual features of wild-type p53 protein in normal human mammary epithelial cells, suggesting a cell type-specific regulation of its expression and function.

Original languageEnglish (US)
Pages (from-to)827-832
Number of pages6
JournalCarcinogenesis
Volume14
Issue number5
DOIs
StatePublished - May 1 1993

Fingerprint

Protein Stability
Breast
Epithelial Cells
Proteins
Fibroblasts
Half-Life
Immunohistochemistry
Monoclonal Antibodies
Missense Mutation
Tumor Cell Line
Immunoprecipitation
Organism Cloning
Rodentia
Staining and Labeling
Breast Neoplasms
Messenger RNA
Mutation

ASJC Scopus subject areas

  • Cancer Research

Cite this

Expression and stability of p53 protein in normal human mammary epithelial cells. / Delmolino, Laurie; Band, Hamid; Band, Vimla.

In: Carcinogenesis, Vol. 14, No. 5, 01.05.1993, p. 827-832.

Research output: Contribution to journalArticle

@article{1e8d107557874c3fb88b3149dfa903af,
title = "Expression and stability of p53 protein in normal human mammary epithelial cells",
abstract = "To examine the p53 protein expressed in human mammary epithelial cell strains grown in vitro we first established the presence of only wild-type p53 and lack of any missense mutations in a representative normal mammary epithelial cell strain, 76N, by cloning and sequencing the entire coding region of the p53 mRNA. The p53 protein expressed in this cell strain and a number of similarly derived normal mammary epithelial cell strains was compared with mammary epithelial tumor cell lines having known p53 mutations and with fibroblasts derived from normal mammary tissue. In all cell strains, immunoprecipitation from metabolically labelled cells using monoclonal antibodies (mAb) PAb 1801 and PAb 122 revealed easily detectable p53 protein. Surprisingly, mAb PAb 1620 (wild type-specific) and PAb 240 (mutant-specific) each immunoprecipitated p53 protein from both normal and tumor cells. Furthermore, p53 protein in normal mammary epithelial cells was shown to be markedly more stable (half-life of ∼3 h) compared to that in mammary fibroblasts or rodent fibroblasts (half-life < 30 min). Immunocytochemistry with PAb 1801 showed detectable p53 protein in normal mammary epithelial cells with a predominantly nuclear staining; however, p53 protein was undetectable in fibroblasts by immunocytochemistry. Together, these results reveal unusual features of wild-type p53 protein in normal human mammary epithelial cells, suggesting a cell type-specific regulation of its expression and function.",
author = "Laurie Delmolino and Hamid Band and Vimla Band",
year = "1993",
month = "5",
day = "1",
doi = "10.1093/carcin/14.5.827",
language = "English (US)",
volume = "14",
pages = "827--832",
journal = "Carcinogenesis",
issn = "0143-3334",
publisher = "Oxford University Press",
number = "5",

}

TY - JOUR

T1 - Expression and stability of p53 protein in normal human mammary epithelial cells

AU - Delmolino, Laurie

AU - Band, Hamid

AU - Band, Vimla

PY - 1993/5/1

Y1 - 1993/5/1

N2 - To examine the p53 protein expressed in human mammary epithelial cell strains grown in vitro we first established the presence of only wild-type p53 and lack of any missense mutations in a representative normal mammary epithelial cell strain, 76N, by cloning and sequencing the entire coding region of the p53 mRNA. The p53 protein expressed in this cell strain and a number of similarly derived normal mammary epithelial cell strains was compared with mammary epithelial tumor cell lines having known p53 mutations and with fibroblasts derived from normal mammary tissue. In all cell strains, immunoprecipitation from metabolically labelled cells using monoclonal antibodies (mAb) PAb 1801 and PAb 122 revealed easily detectable p53 protein. Surprisingly, mAb PAb 1620 (wild type-specific) and PAb 240 (mutant-specific) each immunoprecipitated p53 protein from both normal and tumor cells. Furthermore, p53 protein in normal mammary epithelial cells was shown to be markedly more stable (half-life of ∼3 h) compared to that in mammary fibroblasts or rodent fibroblasts (half-life < 30 min). Immunocytochemistry with PAb 1801 showed detectable p53 protein in normal mammary epithelial cells with a predominantly nuclear staining; however, p53 protein was undetectable in fibroblasts by immunocytochemistry. Together, these results reveal unusual features of wild-type p53 protein in normal human mammary epithelial cells, suggesting a cell type-specific regulation of its expression and function.

AB - To examine the p53 protein expressed in human mammary epithelial cell strains grown in vitro we first established the presence of only wild-type p53 and lack of any missense mutations in a representative normal mammary epithelial cell strain, 76N, by cloning and sequencing the entire coding region of the p53 mRNA. The p53 protein expressed in this cell strain and a number of similarly derived normal mammary epithelial cell strains was compared with mammary epithelial tumor cell lines having known p53 mutations and with fibroblasts derived from normal mammary tissue. In all cell strains, immunoprecipitation from metabolically labelled cells using monoclonal antibodies (mAb) PAb 1801 and PAb 122 revealed easily detectable p53 protein. Surprisingly, mAb PAb 1620 (wild type-specific) and PAb 240 (mutant-specific) each immunoprecipitated p53 protein from both normal and tumor cells. Furthermore, p53 protein in normal mammary epithelial cells was shown to be markedly more stable (half-life of ∼3 h) compared to that in mammary fibroblasts or rodent fibroblasts (half-life < 30 min). Immunocytochemistry with PAb 1801 showed detectable p53 protein in normal mammary epithelial cells with a predominantly nuclear staining; however, p53 protein was undetectable in fibroblasts by immunocytochemistry. Together, these results reveal unusual features of wild-type p53 protein in normal human mammary epithelial cells, suggesting a cell type-specific regulation of its expression and function.

UR - http://www.scopus.com/inward/record.url?scp=0027314750&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0027314750&partnerID=8YFLogxK

U2 - 10.1093/carcin/14.5.827

DO - 10.1093/carcin/14.5.827

M3 - Article

C2 - 8504474

AN - SCOPUS:0027314750

VL - 14

SP - 827

EP - 832

JO - Carcinogenesis

JF - Carcinogenesis

SN - 0143-3334

IS - 5

ER -