These results reveal that the JB oil acted as a chemopreventive dietary agent, inhibiting cell proliferation and COX-2 expression and inducing apoptosis, resulting in a significant reduction in colon tumor formation.
As most sporadic human colon tumors present adenomatous polyposis coli (APC) gene mutations, considerable effort has gone into developing mice that express mutant Apc alleles that mimic human colon cancer pathogenesis.
Using NGS, the following mutations were detected: nonsense mutations in four tumor suppressor genes [APCR1114X (molecular argument that the cancer was a primary tumor of colon), TP53 R213X, RB1 E137X and FBWX7 R393X & S282X], mutations in three receptor tyrosine kinases (RET A919V of high transforming activity, EGFR E114K and FLT3 L601I) well known as oncogenes.
We investigated the presence and patterns of mosaicism in the APC gene in patients with colon neoplasmsnot associated with any other genetic variants; we performed deep sequence analysis of APC in at least 2 adenomas or carcinomas per patient.
APC gene mutations have been associated to have a role in colon cancer and since gastric and colon tumors share some common genetic lesions, it is relevant to investigate the role of APC tumor suppressor gene in gastric cancer.
In Apc(Min) (/+) mice, constitutive CpG methylation of the Fxrα3/4 promoter was linked to reduced (60-90%) baseline Fxr, Ibabp, and Shp and increased Cox-2 expression in apparently normal adjacent mucosa and colon tumors.
Whereas some patients showed a single epigenotype in all tumors throughout the colon, tumors with two distinct epigenotypes developed within a family with the same APC mutation or even within one patient.
We implemented the assay in four cell models: 1) a comparison of proliferating versus epidermal growth factor-stimulated A431 cells, 2) a comparison of SW480Null (mutant APC) and SW480APC (APC restored) colon tumor cell lines, and 3) a comparison of 10 colorectal cancer cell lines with different genomic abnormalities, and 4) lung cancer cell lines with either susceptibility (11-18) or acquired resistance (11-18R) to the epidermal growth factor receptor tyrosine kinase inhibitor erlotinib.
Our findings show that 150 ppm OSU-HDAC42 significantly inhibited small-intestinal polyps (>46%; P < 0.001), with polyp size measuring >1 mm (P < 0.001), and colon tumors (>26%) in APC(min/+)mice, whereas 300 ppm SAHA showed nonsignificant inhibition.
Moreover, CCL2 antagonists decreased intracolonic macrophage infiltration and COX-2 expression, attenuated neovascularization, and eventually reduced the numbers and size of colon tumors, even when given after multiple colon tumors have developed.
We examined the functions of HuR and TTP during colon tumorigenesis and their ability to regulate cyclooxygenase (COX-2), a mediator of prostaglandin synthesis that increases in the colon tumor microenvironment.
Collectively, our data indicate that COX-2 promotes colon tumor progression, but not initiation, and it does so, in part, by activating EGFR and Akt signaling pathways.
APC(Min) mice fed sucrose had an increased tumor number in the proximal third of the small intestine in both studies and a higher incidence of papillary colon tumors in the 16-wk feeding study (P < or = 0.05).
Activation of beta-adrenoceptors and the subsequent stimulation of COX-2, PGE(2), and VEGF expression is perhaps an important mechanism in the tumorigenic action of nicotine on colon tumor growth.
Herein, we demonstrate that 15-PGDH is active in vivo as a highly potent suppressor of colon neoplasia development and acts in the colon as a required physiologic antagonist of the prostaglandin-synthesizing activity of the cyclooxygenase 2 (COX-2) oncogene.
The majority of colon tumors develop because of mutations in the tumor suppressor APC that lead to Wnt/beta-catenin signaling activation and subsequent transcription of target genes, including conductin/AXIN2.
Relatively high folate consumption reduced the risk of APC(-) colon tumors, but folate intake was positively associated with APC(+) colon tumors among men.