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p16 Gene transfer increases cell killing with abnormal nucleation after ionising radiation in glioma cells.

Hama S, Matsuura S, Tauchi H, Yamasaki F, Kajiwara Y, Arita K, Yoshioka H, Heike Y, Mandai K, Kurisu K - Br. J. Cancer (2003)

Bottom Line: It is well established that cells synchronised at the G1-S phase are highly radiosensitive.TUNEL assays and pulse-field gel electrophoresis confirmed that the radiation-induced cell killing of p16-transfected cells could be caused by a nonapoptotic mechanism.Thus, p16 expression prevented radiation-induced apoptosis by promoting abnormal nucleation, thereby leading to another mode of cell death.

View Article: PubMed Central - PubMed

Affiliation: Department of Neurosurgery, Hiroshima University School of Medicine, Kasumi 1-2-3, Minami-ku, Hiroshima 734-8551, Japan. ml-hns@hiroshima-u.ac.jp

ABSTRACT
It is well established that cells synchronised at the G1-S phase are highly radiosensitive. In this study, p16- human glioma cell lines were induced into G1 cell cycle arrest by adenovirus-mediated p16 gene transfer, and examined for radiation-induced cell killing. Clonogenic analysis and trypan blue extraction test showed that the p16 gene transfer enhanced radiation-induced cell killing in p16- glioma cell lines. TUNEL assays and pulse-field gel electrophoresis confirmed that the radiation-induced cell killing of p16-transfected cells could be caused by a nonapoptotic mechanism. Gimsa staining demonstrated that irradiation alone or Ax-mock infection plus irradiation results in a slight increase in the frequency of cells with abnormal nucleus, compared to unirradiated uninfected or Ax-mock infected cells. However, Ax-hp16 or Ax-hp21 infection alone modestly increased the frequency of cells with abnormal nucleus (especially bi- and multinucleation), and 4-Gy irradiation of Ax-hp16 or Ax-hp21 infected cells substantially enhanced this frequency. These results suggest that there exists some unknown interaction between radiation and p16 in cytoplasm/membranes, which decreases cytokinesis and promotes abnormal nucleation. Thus, p16 expression prevented radiation-induced apoptosis by promoting abnormal nucleation, thereby leading to another mode of cell death.

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Related in: MedlinePlus

Effect of p16 transduction on cell-cycle of U251MG and D54MG cells. U251MG (upper) and D54MG cells (lower), nonirradiated or irradiated at a dose of 4 Gy, noninfected or infected with Ax-hp16 or Ax-mock, were cultured for 5 days, and the cell-cycle was analysed by flow cytometry. Data are presented as a histogram, with cell number (Y-axis) plotted against DNA content (X-axis). The first peak contains the cells with diploid DNA at G0/G1. The cells in the second peak with double PI-fluorescence intensity are tetraploid at G2/M. The area between the two peaks contains the cells in the S phase.
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fig2: Effect of p16 transduction on cell-cycle of U251MG and D54MG cells. U251MG (upper) and D54MG cells (lower), nonirradiated or irradiated at a dose of 4 Gy, noninfected or infected with Ax-hp16 or Ax-mock, were cultured for 5 days, and the cell-cycle was analysed by flow cytometry. Data are presented as a histogram, with cell number (Y-axis) plotted against DNA content (X-axis). The first peak contains the cells with diploid DNA at G0/G1. The cells in the second peak with double PI-fluorescence intensity are tetraploid at G2/M. The area between the two peaks contains the cells in the S phase.

Mentions: To determine whether Ax-hp16 infection induced G1 cell-cycle arrest in U251MG or D54MG cells, cell-cycle status was analysed on days 3 and 6 using flow cytometry. Figure 2Figure 2


p16 Gene transfer increases cell killing with abnormal nucleation after ionising radiation in glioma cells.

Hama S, Matsuura S, Tauchi H, Yamasaki F, Kajiwara Y, Arita K, Yoshioka H, Heike Y, Mandai K, Kurisu K - Br. J. Cancer (2003)

Effect of p16 transduction on cell-cycle of U251MG and D54MG cells. U251MG (upper) and D54MG cells (lower), nonirradiated or irradiated at a dose of 4 Gy, noninfected or infected with Ax-hp16 or Ax-mock, were cultured for 5 days, and the cell-cycle was analysed by flow cytometry. Data are presented as a histogram, with cell number (Y-axis) plotted against DNA content (X-axis). The first peak contains the cells with diploid DNA at G0/G1. The cells in the second peak with double PI-fluorescence intensity are tetraploid at G2/M. The area between the two peaks contains the cells in the S phase.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2394396&req=5

fig2: Effect of p16 transduction on cell-cycle of U251MG and D54MG cells. U251MG (upper) and D54MG cells (lower), nonirradiated or irradiated at a dose of 4 Gy, noninfected or infected with Ax-hp16 or Ax-mock, were cultured for 5 days, and the cell-cycle was analysed by flow cytometry. Data are presented as a histogram, with cell number (Y-axis) plotted against DNA content (X-axis). The first peak contains the cells with diploid DNA at G0/G1. The cells in the second peak with double PI-fluorescence intensity are tetraploid at G2/M. The area between the two peaks contains the cells in the S phase.
Mentions: To determine whether Ax-hp16 infection induced G1 cell-cycle arrest in U251MG or D54MG cells, cell-cycle status was analysed on days 3 and 6 using flow cytometry. Figure 2Figure 2

Bottom Line: It is well established that cells synchronised at the G1-S phase are highly radiosensitive.TUNEL assays and pulse-field gel electrophoresis confirmed that the radiation-induced cell killing of p16-transfected cells could be caused by a nonapoptotic mechanism.Thus, p16 expression prevented radiation-induced apoptosis by promoting abnormal nucleation, thereby leading to another mode of cell death.

View Article: PubMed Central - PubMed

Affiliation: Department of Neurosurgery, Hiroshima University School of Medicine, Kasumi 1-2-3, Minami-ku, Hiroshima 734-8551, Japan. ml-hns@hiroshima-u.ac.jp

ABSTRACT
It is well established that cells synchronised at the G1-S phase are highly radiosensitive. In this study, p16- human glioma cell lines were induced into G1 cell cycle arrest by adenovirus-mediated p16 gene transfer, and examined for radiation-induced cell killing. Clonogenic analysis and trypan blue extraction test showed that the p16 gene transfer enhanced radiation-induced cell killing in p16- glioma cell lines. TUNEL assays and pulse-field gel electrophoresis confirmed that the radiation-induced cell killing of p16-transfected cells could be caused by a nonapoptotic mechanism. Gimsa staining demonstrated that irradiation alone or Ax-mock infection plus irradiation results in a slight increase in the frequency of cells with abnormal nucleus, compared to unirradiated uninfected or Ax-mock infected cells. However, Ax-hp16 or Ax-hp21 infection alone modestly increased the frequency of cells with abnormal nucleus (especially bi- and multinucleation), and 4-Gy irradiation of Ax-hp16 or Ax-hp21 infected cells substantially enhanced this frequency. These results suggest that there exists some unknown interaction between radiation and p16 in cytoplasm/membranes, which decreases cytokinesis and promotes abnormal nucleation. Thus, p16 expression prevented radiation-induced apoptosis by promoting abnormal nucleation, thereby leading to another mode of cell death.

Show MeSH
Related in: MedlinePlus