BALB/C DNA was amplified using primers flanking a region within the APC gene containing a HindIII site on the human APC, which is absent in the murine APC (Apc).
In a number of different types of cancer, signalling through beta-catenin is upregulated either by direct mutation of beta-catenin or loss of negative regulation by the APC tumor suppressor protein.
APC helps regulate the cellular level of beta-catenin, which is a downstream mediator in Wnt (Wingless) signaling. beta-Catenin has a nuclear function (binds transcription factors) and a cell membrane function (is a component of epithelial cell adherens junctions).
Adenomatous polyposis coli (APC) gene transcripts skipping exon 14 in combination with the alternatively spliced exons 9 and 10A contribute to the heterogeneity of physiological APC mRNA isoforms.
This review focuses on the three genetically altered mouse models that have been the most widely used in chemoprevention studies: Min mice, which carry a mutation in the adenomatous polyposis coli (APC) gene; APC-knockout mice; and p53-knockout mice.
Studies with the Min and APC-knockout mice provide the strongest evidence to date that the enzyme cyclooxygenase-2 plays a major role in colon carcinogenesis, and that nonsteroidal anti-inflammatory drugs that target cyclooxygenase-2 have great potential as colon cancer chemopreventive agents.
Germline mutation of the APC gene and subsequent somatic mutation of the second APC allele cause the inherited familial adenomatous polyposis syndrome.
In order to define the thrombophilic conditions related to activated protein C resistance (APC-R) and protein S (PS) deficiency and to detect the possible combination of these defects, we studied nine unrelated patients selected because of low anticoagulant response to APC and reduced PS activity with at least one first degree relative having the same coagulation feature.
The proposita of family B, referred for superficial thrombophlebitis, had low plasminogen levels (activity 55% and antigen 53%) and APC resistance (APC-SR = 1.5) whereas the asymptomatic mother and the brother had isolated APC resistance (APC-SR = 1.62 and 1.8, respectively) and the asymptomatic father isolated plasminogen deficiency (activity 61% and antigen 62%).
The physical interaction between beta-catenin and the adenomatous polyposis coli (APC) gene, and the ability of APC to regulate cytoplasmic levels of beta-catenin suggest a role for beta-catenin in colorectal carcinogenesis.
The physical interaction between beta-catenin and the adenomatous polyposis coli (APC) gene, and the ability of APC to regulate cytoplasmic levels of beta-catenin suggest a role for beta-catenin in colorectal carcinogenesis.
To determine whether beta-catenin protein level was responsible for the change in proliferation rate, stable transfections of deltaN89beta-catenin (a stabilized form that is not degraded by APC, but retains all other functions) were achieved in half of the cultures derived from each tumor, whereas the other half were transfected with an empty vector.
These findings support a model where somatic instability of the (A)8 tract produced by the APCI1307K allele leads to increased APC gene inactivation and directly accounts for 42% of the colorectal neoplasms occurring in APCI1307K carriers.
FAP kindreds without detected APC gene mutations present with a notably milder disease phenotype compared with APC positive families, suggesting that different genetic factors might be involved.
Extracolonic lesions characteristic of FAP occurred with 3' APC mutations, but variability in intrapedigree and interpedigree extracolonic phenotype and dissociation of severity of extracolonic manifestations from number of colorectal polyps was noted.
In this study, direct mutation analysis of the APC gene was performed to determine genotype-phenotype correlations for nine extracolonic manifestations and to investigate the incidence of APC mutations in non-FAP colorectal cancer.
One PAC (G21100) provided evidence for the presence of a novel complex repeat unit, indicating that there are at least three independent repeat elements within 2 Mb.
In contrast, mutant APC gene products that are associated with attenuated polyposis (codon 386 or 1465) interfered only weakly with wild-type APC activity.