TY - JOUR
T1 - Evidence that senescent human prostate epithelial cells enhance tumorigenicity
T2 - Cell fusion as a potential mechanism and inhibition by p16INK4a and hTERT
AU - Bhatia, Bobby
AU - Multani, Asha S.
AU - Patrawala, Lubna
AU - Chen, Xin
AU - Calhoun-Davis, Tammy
AU - Zhou, Jianjun
AU - Schroeder, Lisa
AU - Schneider-Broussard, Robin
AU - Shen, Jianjun
AU - Pathak, Sen
AU - Chang, Sandy
AU - Tang, Dean G.
PY - 2008/4/1
Y1 - 2008/4/1
N2 - Normal human prostate (NHP) epithelial cells undergo senescence in vitro and in vivo but the potential role of senescent NHP cells in prostate tumorigenesis remain unclear. Here we show that senescent NHP cells enhance the in vivo tumorigenicity of low-tumorigenic LNCaP prostate cancer and low/non-tumorigenic subset of cells (called L cells) isolated from multiple bulk-cultured prostate (and other) cancer cell lines. Subsequent studies suggest cell-cell fusion as a potential mechanism for senescent NHP cell-enhanced tumor development. Using fluorescently tagged tumor cells and/or NHP cells, we find that NHP cells, like fibroblasts, can undergo fusion with unfractionated tumor cells or the L cells. Using 293T-L cells as the model cell system, we verify NHP and 293T-L cell fusion by using differential RT-PCR, karyotyping, and gene expression analyses. Further experiments demonstrate that senescent NHP cells that have lost progenitor markers, accumulated p16INK4a (p16) protein expression, and acquired the AR mRNA expression, appear to be the preferential fusion targets. Strikingly, the tumorigenicity of the NHP/293T-L hybrid cells was inhibited by exogenous p16 as well as hTERT. Chromosomal analyses revealed that hTERT probably inhibited the in vivo tumorigenicity by maintaining genomic stability. These results suggest that senescent NHP cells, like senescent fibroblasts, may promote tumor development and that one of the mechanisms underlying the senescent NHP cell-enhanced tumorigenicity could be through cell fusion.
AB - Normal human prostate (NHP) epithelial cells undergo senescence in vitro and in vivo but the potential role of senescent NHP cells in prostate tumorigenesis remain unclear. Here we show that senescent NHP cells enhance the in vivo tumorigenicity of low-tumorigenic LNCaP prostate cancer and low/non-tumorigenic subset of cells (called L cells) isolated from multiple bulk-cultured prostate (and other) cancer cell lines. Subsequent studies suggest cell-cell fusion as a potential mechanism for senescent NHP cell-enhanced tumor development. Using fluorescently tagged tumor cells and/or NHP cells, we find that NHP cells, like fibroblasts, can undergo fusion with unfractionated tumor cells or the L cells. Using 293T-L cells as the model cell system, we verify NHP and 293T-L cell fusion by using differential RT-PCR, karyotyping, and gene expression analyses. Further experiments demonstrate that senescent NHP cells that have lost progenitor markers, accumulated p16INK4a (p16) protein expression, and acquired the AR mRNA expression, appear to be the preferential fusion targets. Strikingly, the tumorigenicity of the NHP/293T-L hybrid cells was inhibited by exogenous p16 as well as hTERT. Chromosomal analyses revealed that hTERT probably inhibited the in vivo tumorigenicity by maintaining genomic stability. These results suggest that senescent NHP cells, like senescent fibroblasts, may promote tumor development and that one of the mechanisms underlying the senescent NHP cell-enhanced tumorigenicity could be through cell fusion.
KW - Cell fusion
KW - Cell senescence
KW - P16
KW - Prostate epithelial cells
KW - hTERT
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U2 - 10.1002/ijc.23222
DO - 10.1002/ijc.23222
M3 - Article
C2 - 18059027
AN - SCOPUS:39649122634
SN - 0020-7136
VL - 122
SP - 1483
EP - 1495
JO - International journal of cancer
JF - International journal of cancer
IS - 7
ER -