TY - JOUR
T1 - Knockdown of p53 combined with expression of the catalytic subunit of telomerase is sufficient to immortalize primary human ovarian surface epithelial cells
AU - Yang, Gong
AU - Rosen, Daniel G.
AU - Mercado-Uribe, Imelda
AU - Colacino, Justin A.
AU - Mills, Gordon B.
AU - Bast, Robert C.
AU - Zhou, Chenyi
AU - Liu, Jinsong
N1 - Funding Information:
We thank Drs Sandy Chang and Asha Multani from the Molecular Cytogenetics Core facility at M. D. Anderson for karyotyping the immortalized cells. J.L. is supported by a Research Scholar Grant (RSG-04-028-1-CCE) from the American Cancer Society and by an Ovarian SPORE grant (IP50CA83638). This work is also supported in part by Cancer Center Core grant (CA016672) from the National Cancer Institute.
PY - 2007/1
Y1 - 2007/1
N2 - Ovarian cancer is developed from a single layer of thin epithelial cells covering the surface of ovary, named human ovarian surface epithelial cells. Like all primary human cells, human ovarian surface epithelial cells have a finite life span and will go into senescence and eventually die when cultured in vitro. Immortalized human ovarian surface epithelial cells will provide an important model system with which to study ovarian cancer initiation and progression. Here, we show that silencing p53 expression with retrovirus-mediated small interfering RNA can delay the senescence and extend cell passage number, but is not sufficient to immortalize normal ovarian surface epithelial cells. Introduction of the catalytic subunit of telomerase is similarly insufficient to achieve immortalization. However, concurrent disruption of p53 expression with small interfering RNA retroviral constructs and ectopic expression of the catalytic subunit of telomerase was sufficient to induce cellular immortalization in 3 of 3 human ovarian surface epithelial cell cultures tested. The immortalzation is associated with increased telomerase activity and telomere length, and attenuated response of cell-cycle regulatory proteins to irradiation. The resultant immortal cells continued to express the same specific cytokeratins 8 and 18 as parental cells did, indicating that the epithelial characters are still maintained in the immortal cells. In addition, the immortalized cells are non-tumorigenic and nearly diploid, which is in constrast with one immortalized by SV40 T/t antigens and hTERT. As both p53 pathway dysfunction and activation of telomerase are commonly present in human ovarian cancer, these immortal cells provide an authetic cell model system for the study of the human ovarian cancer initiation, progression, differentiation and chemoprevention.
AB - Ovarian cancer is developed from a single layer of thin epithelial cells covering the surface of ovary, named human ovarian surface epithelial cells. Like all primary human cells, human ovarian surface epithelial cells have a finite life span and will go into senescence and eventually die when cultured in vitro. Immortalized human ovarian surface epithelial cells will provide an important model system with which to study ovarian cancer initiation and progression. Here, we show that silencing p53 expression with retrovirus-mediated small interfering RNA can delay the senescence and extend cell passage number, but is not sufficient to immortalize normal ovarian surface epithelial cells. Introduction of the catalytic subunit of telomerase is similarly insufficient to achieve immortalization. However, concurrent disruption of p53 expression with small interfering RNA retroviral constructs and ectopic expression of the catalytic subunit of telomerase was sufficient to induce cellular immortalization in 3 of 3 human ovarian surface epithelial cell cultures tested. The immortalzation is associated with increased telomerase activity and telomere length, and attenuated response of cell-cycle regulatory proteins to irradiation. The resultant immortal cells continued to express the same specific cytokeratins 8 and 18 as parental cells did, indicating that the epithelial characters are still maintained in the immortal cells. In addition, the immortalized cells are non-tumorigenic and nearly diploid, which is in constrast with one immortalized by SV40 T/t antigens and hTERT. As both p53 pathway dysfunction and activation of telomerase are commonly present in human ovarian cancer, these immortal cells provide an authetic cell model system for the study of the human ovarian cancer initiation, progression, differentiation and chemoprevention.
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U2 - 10.1093/carcin/bgl115
DO - 10.1093/carcin/bgl115
M3 - Article
C2 - 16829690
AN - SCOPUS:33845621580
SN - 0143-3334
VL - 28
SP - 174
EP - 182
JO - Carcinogenesis
JF - Carcinogenesis
IS - 1
ER -