Related Experiment Video

Updated: Jul 29, 2026

Deficient Pms2, ERCC1, Ku86, CcOI in Field Defects During Progression to Colon Cancer
28:15

Deficient Pms2, ERCC1, Ku86, CcOI in Field Defects During Progression to Colon Cancer

Published on: July 28, 2010

Susceptibility to carcinogenesis

A E Reif

    Cancer
    |June 15, 1986
    PubMed

    Insights

    The spontaneous incidence of a tumor type influences carcinogen-induced tumor rates. Carcinogen testing is most sensitive when spontaneous tumor incidence is low or subthreshold.

    Area of Science:

    • Oncology
    • Carcinogenesis Research

    Background:

    • The relationship between spontaneous tumor incidence and carcinogen-induced tumors is complex.
    • Previous reviews have analyzed related subjects, necessitating a re-examination of data to avoid bias.

    Purpose of the Study:

    • To investigate the influence of spontaneous tumor incidence on carcinogen-induced tumor rates.
    • To mathematically eliminate confounding factors affecting carcinogenesis.
    • To determine optimal conditions for carcinogen assays.

    Main Methods:

    • Analysis of qualitative and quantitative evidence from a previous review.
    • Mathematical elimination of factors influencing carcinogenesis.
    • Examination of unselected carcinogenesis data.

    Main Results:

    • Spontaneous tumor incidence can be a factor in carcinogen-induced tumor rates.
    • When other factors are not eliminated, spontaneous incidence may appear to have no effect.
    • Carcinogens enhance the conversion of normal cells to cancer cells.

    Conclusions:

    • Spontaneous tumor incidence is a weak factor with incomplete penetrance, often outweighed by other factors.
    • Carcinogen assays are most sensitive when the target tumor type has a low or subthreshold spontaneous incidence.
    • Further evidence is needed to definitively prove this relationship.

    More Related Videos

    Intramucosal Inoculation of Squamous Cell Carcinoma Cells in Mice for Tumor Immune Profiling and Treatment Response Assessment07:29

    Intramucosal Inoculation of Squamous Cell Carcinoma Cells in Mice for Tumor Immune Profiling and Treatment Response Assessment

    Published on: April 22, 2019

    Chemical-Induced Skin Carcinogenesis Model Using Dimethylbenz[a]Anthracene and 12-O-Tetradecanoyl Phorbol-13-Acetate (DMBA-TPA)04:12

    Chemical-Induced Skin Carcinogenesis Model Using Dimethylbenz[a]Anthracene and 12-O-Tetradecanoyl Phorbol-13-Acetate (DMBA-TPA)

    Published on: December 19, 2019

    Related Concept Videos

    Cancers Originate from Somatic Mutations in a Single Cell02:21

    Cancers Originate from Somatic Mutations in a Single Cell

    Cancer arises from mutations in the critical genes that allow healthy cells to escape cell cycle regulation and acquire the ability to proliferate indefinitely. Though originating from a single mutation event in one of the originator cells, cancer progresses when the mutant cell lines continue to gain more and more mutations, and finally, become malignant. For example, chronic myelogenous leukemia (CML) develops initially as a non-lethal increase in white blood cells, which progressively...
    Adaptive Mechanisms in Cancer Cells02:53

    Adaptive Mechanisms in Cancer Cells

    Cancer cells accumulate genetic changes at an abnormally rapid rate due to the defects in the DNA repair mechanisms. From an evolutionary perspective, such genetic instability is advantageous for cancer development. Mutant cell lines accumulate a series of beneficial mutations that contribute to their progression into cancer.
    Some of the advantages that cancer cells have on normal cells include - enhanced ability to divide without terminally differentiating, induce new blood vessel formation,...
    Cancer-Critical Genes I: Proto-oncogenes01:33

    Cancer-Critical Genes I: Proto-oncogenes

    Genes usually encode proteins necessary for the proper functioning of a healthy cell. Mutations can often cause changes to the gene expression pattern, thereby altering the phenotype.
    When the function of certain critical genes, especially those involved in cell cycle regulation and cell growth signaling cascades, gets disrupted, it upsets the cell cycle progression. Such cells with unchecked cell cycles start proliferating uncontrollably and eventually develop into tumors.
    Such genes that act...
    Cancer Prevention02:59

    Cancer Prevention

    Several factors can increase the risk of cancer in an individual. About 50% of cancer cases can be prevented by adopting a healthy lifestyle, regular exercise, eating healthy, and following a modest cancer prevention diet. Epidemiological studies have consistently shown that populations with vegetable and fruit-rich diets have reduced the incidence of cancer. On the other hand, populations who have a diet rich in animal fat, red meat, junk food, or high calories are predisposed to cancer.
    Some...
    Skin Cancer01:30

    Skin Cancer

    Skin cancer is a type of cancer that occurs when there is an abnormal growth of skin cells, usually triggered by damage to the DNA within the skin cells. It is primarily caused by exposure to ultraviolet (UV) radiation from the sun or artificial sources like tanning beds. Skin cancer is the most common type of cancer worldwide, and its incidence continues to rise.
    Basal Cell Carcinoma (BCC): BCC is the most common type of skin cancer, accounting for about 80% of cases. It typically develops in...
    Mutagenicity and Carcinogenicity01:25

    Mutagenicity and Carcinogenicity

    Mutagenicity and carcinogenicity refer to the ability of drugs to cause genetic defects and induce cancer, respectively. The International Agency for Research on Cancer (IARC) classifies agents into four groups based on their carcinogenic potential. Group 1 agents are known human carcinogens; group 2A agents are probably carcinogenic to humans; group 3 agents lack data to support their role in carcinogenesis; and group 4 includes agents for which data support that they are not likely to be...