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.
Compared with colorectal adenocarcinomas, mixed adenoneuroendocrine carcinomas were more frequently BRAF (37%; P=0.006), and less frequently KRAS (21%; P=0.043) and APC (16%; P=0.001) mutated.
Molecular analyses revealed the gene mutations of GNAS in 6 (38%) of 16 DNGPs (4 [57%] adenomas, 1 [16%] NUMP, and 1 [33%] invasive adenocarcinoma) and APC in 4 of 15 (27%) DNGPs: no adenomas, 2 (33%) NUMPs, and 2 (67%) invasive adenocarcinomas.
This autosomal-dominant syndrome is caused by germline mutations in the gene coding for the protein APC and leads to hyperactivation of the WNT/β-catenin signaling pathway, uncontrolled intestinal cell proliferation and formation of adenocarcinomas.
Formalin Fixed Paraffin Embedded tissue were studied for miRNA expression, KRAS, BRAF, PIK3CA mutations, and immuno-histochemistry for APC and p53 proteins for normal colon (n=11), hyperplastic polyps (n=11), high grade adenomas (n=10), low grade adenomas (n=34) and adenocarcinoma (n=13).
Most sporadic colonic adenocarcinomas are microsatellite stable (MSS) and arise from conventional adenomas by dysregulation of the APC/β-catenin/Wnt signaling pathway.
APC, KRAS, and BRAF mutations were identified in five, 11, and one lesion, respectively, and most of these mutations were shared between the villous adenoma and the adenocarcinoma components in the respective lesions, except in one lesion with APC mutations and in two lesions with KRAS mutations.
Truncating mutations of RNF43 are more prevalent in microsatellite-unstable tumors and show mutual exclusivity with inactivating APC mutations in colorectal adenocarcinomas.
Loss of DCC-induced apoptosis is also associated with an increase in the number and aggressiveness of intestinal tumours in a predisposing APC mutant context, resulting in the development of highly invasive adenocarcinomas.
Forty-eight small bowel adenocarcinomas (33 non-celiac disease related and 15 celiac disease related) were characterized for chromosomal aberrations by high-resolution array comparative hybridization, microsatellite instability, and APC promoter methylation and mutation status.
Could APC gene screening be useful in children with hepatoblastoma? Early onset of adenocarcinoma in a child with familial adenomatous polyposis and hepatoblastoma.
Preoperative measurement of methylated DAPK and APC promoter DNA in peripheral blood may contribute to better estimate postoperative survival chances of patients with esophageal carcinoma, especially adenocarcinoma.
Alterations of APC, KRAS and TP53 were observed in a higher percentage of adenocarcinomas compared to adenomas (P<0.05) indicating that the alterations accumulated with malignancy.
We analyzed the phenotypes, DNA ploidy patterns, and microsatellite regions linked to adenomatous polyposis coli (APC) gene on chromosome 5q of low-grade gastric adenomas/dysplasias, Vienna Category 3, to investigate whether these lesions have the potential to become adenocarcinomas.
We analyzed the phenotypes, DNA ploidy patterns, and microsatellite regions linked to adenomatous polyposis coli (APC) gene on chromosome 5q of low-grade gastric adenomas/dysplasias, Vienna Category 3, to investigate whether these lesions have the potential to become adenocarcinomas.
In comparison with adenocarcinomas of the stomach, SB-AC revealed a significantly higher rate of hypermethylation of HPP1 (86% versus 54%, p = 0.0003), p16(INK4A) (32% versus 10%, p = 0.0006), and a significantly lower rate of hypermethylation of APC (48% versus 84%, p = 0.0001).
A distinct profile was apparent for the 2 groups of lung tumors and the frequencies of promoter hypermethylation at sFRP1 and WIF-1, 2 genes involved in Wnt signaling, and at CDH1 were significantly higher in colorectal metastases than in lung primaries, whereas methylation of the APC promoter was significantly more common in lung primary adenocarcinomas.
Combining 4 genes (CALCA, DAPK, ESR1 and APC) yielded a sensitivity of 89% (with all adenocarcinomas identified), equal to cytomorphology (89%) and high-risk human papilloma virus (Hr-HPV; 90%).