CDDP induces p53-dependent apoptosis in tongue cancer cells.
We have investigated the CDDP sensitivities of two tongue cancer cell lines with differing p53 genetic status, one with wild-type p53 (SAS) and the other with mutant-type p53 (HSC-4). SAS was about 2 times more sensitive at the D10 dose and demonstrated increased p53 and Bax protein levels at 10 h after CDDP treatment on Western blot analysis. On the other hand, overexpression of p53 in HSC-4 was observed without CDDP treatment and no elevation of Bax could be detected. Apoptosis was observed after CDDP treatment in SAS but not in HSC-4 by Hoechst 33342-staining and electrophoresis methods. These findings indicate that p53 plays an important role in apoptosis as a positive regulator of Bax expression. It is suggested that p53 status may have predictive potential with regard to response to CDDP therapy.
Kanata
H
H
Department of Otorhinolaryngology, NARA Medical University, Kashihara, Nara, Japan. jibika@nmu-gw.naramed-u.ac.jp
Yane
K
K
Ota
I
I
Miyahara
H
H
Matsunaga
T
T
Takahashi
A
A
Ohnishi
K
K
Ohnishi
T
T
Hosoi
H
H
D017209:Apoptosis / Q000187:drug effects*; D002294:Carcinoma, Squamous Cell / Q000235:genetics / Q000473:pathology*; D002945:Cisplatin / Q000494:pharmacology*; D004273:DNA, Neoplasm / Q000235:genetics; D019008:Drug Resistance, Neoplasm; D016158:Genes, p53; D006801:Humans; D009363:Neoplasm Proteins / Q000096:biosynthesis / Q000502:physiology*; D016133:Polymerase Chain Reaction; D018807:Polymorphism, Single-Stranded Conformational; D011518:Proto-Oncogene Proteins / Q000096:biosynthesis; D019253:Proto-Oncogene Proteins c-bcl-2; D014062:Tongue Neoplasms / Q000235:genetics / Q000473:pathology*; D014407:Tumor Cells, Cultured / Q000187:drug effects / Q000473:pathology; D016159:Tumor Suppressor Protein p53 / Q000096:biosynthesis / Q000502:physiology*; D051028:bcl-2-Associated X Protein
C494826:BAX protein, human; D004273:DNA, Neoplasm; D009363:Neoplasm Proteins; D011518:Proto-Oncogene Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D016159:Tumor Suppressor Protein p53; D051028:bcl-2-Associated X Protein; D002945:Cisplatin