Promoter of TRAIL-R2 gene.
Yoshida Tatsushi,Sakai Toshiyuki
Vitamins and hormones
TRAIL-R2 promoter does not have a typical TATA-box but two functional Sp1-binding sites. TRAIL-R2 promoter belongs to the class of TATA-less and GC-box-containing promoters. The minimal promoter element is contained in the region spanning -198 to -116 upstream of translational initiation codon ATG. Computer analysis shows putative transcription factor binding sites such as c-Ets, AML-1a, c-Myb, Sp1, and GATA-1 in TRAIL-R2 promoter. Hypermethylation of TRAIL-R2 is not frequent compared with that of TRAIL-R3 and TRIAL-R4. There are no potential transcription factor binding sites in highly homologous regions between TRAIL-R2 promoter and TRAIL-R1 promoter, or between TRAIL-R2 promoter and mouse homologue mouse killer (MK) promoter. TRAIL-R2 is known to be a downstream gene of p53, a tumor-suppressor gene, and a p53-binding site in TRAIL-R2 intron 1 is responsible for p53-dependent transcription. Thapsigargin, endoplasmic reticulum Ca(2+)-ATPase inhibitor calcium releaser, upregulates TRAIL-R2 expression via the promoter region. Many regulators of TRAIL-R2 have been reported. However, it has not been demonstrated whether they regulate TRAIL-R2 via the promoter region. Here, we show a list of these regulators. Finally, we demonstrate the possibility of cancer therapy using regulation of TRAIL-R2 promoter.
10.1016/S0083-6729(04)67003-8
WNT2 and human gastrointestinal cancer (review).
Katoh Masaru
International journal of molecular medicine
WNT2 gene on human chromosome 7q31 is a paralog of the WNT2B gene on human chromosome 1p13. Rat Wnt2 gene was identified within rat genome draft sequence AC095247.4. Human WNT2 showed 96.4% total-amino-acid identity with rat Wnt2, 96.1% with mouse Wnt2, 68.6% with zebrafish wnt2, and 67.8% with fugu wnt2. WNT2 is an evolutionarily conserved secreted-type glycoprotein belonging to the WNT family. WNT2 mRNA is expressed in human fetal lung and placenta, but almost undetectable in normal gastrointestinal tract. WNT2 mRNA is frequently up-regulated in human gastric cancer due to tumor-stromal interaction, and WNT2 gene is rarely amplified in human gastric cancer. WNT2 mRNA is also frequently up-regulated in colorectal polyps, primary colorectal cancer of stage A-C, and also in liver metastasis from colorectal cancer. Putative biding sites for estrogen receptor, GATA-1, AP-2, TCF-1, BHLH, MBF-I, p53, and HNF-5 are located within the 5'-flanking region of human WNT2 gene. WNT2 is up-regulated by beta-estradiol in human MCF-7 cells; however, the mechanism of WNT2 up-regulation in most cases of gastrointestinal cancer remains to be elucidated. WNT2 is a tumor marker of gastric and colorectal cancer. Detection of theWNT2 protein in feces by immunohistochemistry or ELISA and WNT2 mRNA in feces by cDNA-PCR or custom-made microarray could be applied for screening of colorectal cancer. Because WNT2 up-regulation leads to carcinogenesis through activation of the WNT-beta-catenin pathway, WNT2 specific antagonist might be applied for chemoprevention or treatment of gastrointestinal cancer. WNT2 gene is one of the targets for pharmacogenomics in the field of oncology.