APC mutations were identified in duodenal adenomas more frequently than in duodenal ACs, which differed from the observations of typical adenoma-carcinoma sequences seen in colorectal cancer, suggesting the limited involvement of this mechanism in duodenal cancer development.
A subset of APC mutation carriers shows a milder familial adenomatous polyposis phenotype (attenuated FAP) developing smaller number of polyps and colorectal cancer at an older age.
Although APC loss is considered an initiating event in colorectal cancer, for example, it is less clear what role APC plays in tumor cell motility and whether loss of APC might be an important promoter of tumor progression in addition to initiation.
Although less eminent than protein truncation by point mutation within the coding region of the APC gene, epigenetic alteration suppressing APC gene expression may significantly contribute to oncogenesis and the progression of colorectal cancer.
Although the APC gene was first sequenced over a decade ago, new functions are still being described and its importance in the genesis of colorectal cancer continues to increase.
An adenomatous polyposis coli (APC) gene variant (I1307K allele), which was recently reported in 1 in 17 Ashkenazi Jewish persons, may double the risk for colorectal cancer in that population.
An APC gene sequence alteration, the I1307K allele, occurs in 6% of the Ashkenazi Jewish population and is reported to double the risk for colorectal cancer.
AXIN2 and MUTYH genes were screened for germline mutations by PCR and direct sequencing in 39 unrelated patients with multiple adenomas or colorectal cancer without evidence of APC mutation nor mismatch repair defect.
Biallelic mutation of the ADENOMATOUS POLYPOSIS COLI (APC) gene is a hallmark of sporadic colorectal cancer and colorectal, duodenal and desmoid tumours that develop in familial adenomatous polyposis (FAP) patients.
Cancers in hereditary non-polyposis colorectal cancer show features of both classical (adenoma and APC mutation) and alternative pathways (rapid evolution, MSI-H and lack of chromosomal instability).