TY - JOUR
T1 - MUTYH, an adenine DNA glycosylase, mediates p53 tumor suppression via PARP-dependent cell death
AU - Oka, S.
AU - Leon, J.
AU - Tsuchimoto, D.
AU - Sakumi, K.
AU - Nakabeppu, Y.
N1 - Publisher Copyright:
© 2014 Macmillan Publishers Limited.
PY - 2014/1/1
Y1 - 2014/1/1
N2 - p53-regulated caspase-independent cell death has been implicated in suppression of tumorigenesis, however, the regulating mechanisms are poorly understood. We previously reported that 8-oxoguanine (8-oxoG) accumulation in nuclear DNA (nDNA) and mitochondrial DNA triggers two distinct caspase-independent cell death through buildup of single-strand DNA breaks by MutY homolog (MUTYH), an adenine DNA glycosylase. One pathway depends on poly-ADP-ribose polymerase (PARP) and the other depends on calpains. Deficiency of MUTYH causes MUTYH-associated familial adenomatous polyposis. MUTYH thereby suppresses tumorigenesis not only by avoiding mutagenesis, but also by inducing cell death. Here, we identified the functional p53-binding site in the human MUTYH gene and demonstrated that MUTYH is transcriptionally regulated by p53, especially in the p53/DNA mismatch repair enzyme, MLH1-proficient colorectal cancer-derived HCT116+Chr3 cells. MUTYH-small interfering RNA, an inhibitor for p53 or PARP suppressed cell death without an additive effect, thus revealing that MUTYH is a potential mediator of p53 tumor suppression, which is known to be upregulated by MLH1. Moreover, we found that the p53-proficient, mismatch repair protein, MLH1-proficient colorectal cancer cell line express substantial levels of MUTYH in nuclei but not in mitochondria, suggesting that 8- oxoG accumulation in nDNA triggers MLH1/PARP-dependent cell death. These results provide new insights on the molecular mechanism of tumorigenesis and potential new strategies for cancer therapies
AB - p53-regulated caspase-independent cell death has been implicated in suppression of tumorigenesis, however, the regulating mechanisms are poorly understood. We previously reported that 8-oxoguanine (8-oxoG) accumulation in nuclear DNA (nDNA) and mitochondrial DNA triggers two distinct caspase-independent cell death through buildup of single-strand DNA breaks by MutY homolog (MUTYH), an adenine DNA glycosylase. One pathway depends on poly-ADP-ribose polymerase (PARP) and the other depends on calpains. Deficiency of MUTYH causes MUTYH-associated familial adenomatous polyposis. MUTYH thereby suppresses tumorigenesis not only by avoiding mutagenesis, but also by inducing cell death. Here, we identified the functional p53-binding site in the human MUTYH gene and demonstrated that MUTYH is transcriptionally regulated by p53, especially in the p53/DNA mismatch repair enzyme, MLH1-proficient colorectal cancer-derived HCT116+Chr3 cells. MUTYH-small interfering RNA, an inhibitor for p53 or PARP suppressed cell death without an additive effect, thus revealing that MUTYH is a potential mediator of p53 tumor suppression, which is known to be upregulated by MLH1. Moreover, we found that the p53-proficient, mismatch repair protein, MLH1-proficient colorectal cancer cell line express substantial levels of MUTYH in nuclei but not in mitochondria, suggesting that 8- oxoG accumulation in nDNA triggers MLH1/PARP-dependent cell death. These results provide new insights on the molecular mechanism of tumorigenesis and potential new strategies for cancer therapies
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U2 - 10.1038/oncsis.2014.35
DO - 10.1038/oncsis.2014.35
M3 - Article
AN - SCOPUS:84927702435
VL - 3
JO - Oncogenesis
JF - Oncogenesis
SN - 2157-9024
IS - 10
M1 - e121
ER -