Related Experiment Video

Updated: Aug 1, 2026

Yeast As a Chassis for Developing Functional Assays to Study Human P53
14:57

Yeast As a Chassis for Developing Functional Assays to Study Human P53

Published on: August 4, 2019

p53 knockout mice (-/-) are more susceptible than (+/-) or (+/+) mice to N-methyl-N-nitrosourea stomach

M Yamamoto1, T Tsukamoto, H Sakai

  • 1Division of Oncological Pathology, Aichi Cancer Center Research Institute, 1-1 Kanokoden, Chikusa, Nagoya 464-8681, Japan.

Carcinogenesis
|October 7, 2000
PubMed

Insights

Mice lacking the p53 tumor suppressor gene showed increased susceptibility to N-methyl-N-nitrosourea (MNU) induced gastric preneoplastic lesions and tumors. This suggests p53 acts as a gatekeeper in MNU-induced stomach carcinogenesis.

Area of Science:

  • Oncology
  • Genetics
  • Toxicology

Background:

  • Mutations in the p53 tumor suppressor gene are common in human cancers.
  • p53-deficient mice are utilized to identify chemical genotoxins.
  • Gastric carcinogenesis is a significant area of cancer research.

Purpose of the Study:

  • To investigate the role of p53 in N-methyl-N-nitrosourea (MNU) induced gastric carcinogenesis.
  • To assess the susceptibility of p53 knockout mice to MNU.
  • To determine if p53 is a direct target of MNU.

Main Methods:

  • p53 nullizygote, heterozygote, and wild-type mice were treated with MNU.
  • Gastric lesions and tumors were quantified after 5 and 15 weeks.
  • PCR-single strand conformation polymorphism analysis was used to detect p53 mutations.

Main Results:

  • p53 nullizygote mice exhibited significantly higher numbers of pepsinogen-altered pyloric glands (PAPG) and gastric adenomas.
  • Adenocarcinomas and other tumors (lymphomas, leukemias, sarcomas) were observed in p53-deficient mice.
  • No p53 mutations were detected in gastric tumors from MNU-treated mice.

Conclusions:

  • p53 plays a crucial gatekeeper role in MNU-induced mouse stomach carcinogenesis.
  • MNU does not appear to directly target the p53 gene.
  • p53 deficiency enhances susceptibility to MNU-induced gastric lesions and tumors.

More Related Videos

Defining Gene Functions in Tumorigenesis by Ex vivo Ablation of Floxed Alleles in Malignant Peripheral Nerve Sheath Tumor Cells09:37

Defining Gene Functions in Tumorigenesis by Ex vivo Ablation of Floxed Alleles in Malignant Peripheral Nerve Sheath Tumor Cells

Published on: August 25, 2021

Detection of Aggregation-Prone Behavior in Mutant P53 V157F Breast Cancer Cells Using Multipoint Thioflavin T Fluorescence04:56

Detection of Aggregation-Prone Behavior in Mutant P53 V157F Breast Cancer Cells Using Multipoint Thioflavin T Fluorescence

Published on: December 30, 2025

Related Concept Videos

In-vitro Mutagenesis01:16

In-vitro Mutagenesis

To learn more about the function of a gene, researchers can observe what happens when the gene is inactivated or “knocked out,” by creating genetically engineered knockout animals. Knockout mice have been particularly useful as models for human diseases such as cancer, Parkinson’s disease, and diabetes.
DNA Damage can Stall the Cell Cycle02:36

DNA Damage can Stall the Cell Cycle

In response to DNA damage, cells can pause the cell cycle to assess and repair the breaks. However, the cell must check the DNA at certain critical stages during the cell cycle. If the cell cycle pauses before DNA replication, the cells will contain twice the amount of DNA. On the other hand, if cells arrest after DNA replication but before mitosis, they will contain four times the normal amount of DNA. With a host of specialized proteins at their disposal,cells must use the right protein at...
Abnormal Proliferation02:23

Abnormal Proliferation

Under normal conditions, most adult cells remain in a non-proliferative state unless stimulated by internal or external factors to replace lost cells. Abnormal cell proliferation is a condition in which the cell's growth exceeds and is uncoordinated with normal cells. In such situations, cell division persists in the same excessive manner even after cessation of the stimuli, leading to persistent tumors. The tumor arises from the damaged cells that replicate to pass the damage to the daughter...
Mouse Models of Cancer Study02:43

Mouse Models of Cancer Study

Mice have long served as models for studying human biology and pathology because of their phylogenetic and physiological similarity with humans. They are also easy to maintain and breed in the laboratory, and hence, many inbred strains are now available for research. Studies on mice have contributed immeasurably to our understanding of cancer biology.
The development of transgenic, knockout, and knock-in mice has led to an exponential increase in their use as model organisms in research,...
DNA Damage Can Stall the Cell Cycle02:36

DNA Damage Can Stall the Cell Cycle

In response to DNA damage, cells can pause the cell cycle to assess and repair the breaks. However, the cell must check the DNA at certain critical stages during the cell cycle. If the cell cycle pauses before DNA replication, the cells will contain twice the amount of DNA. On the other hand, if cells arrest after DNA replication but before mitosis, they will contain four times the normal amount of DNA. With a host of specialized proteins at their disposal,cells must use the right protein at...