Search

Supplementary Table 1 from Activin Type II Receptor Restoration in ACVR2-Deficient Colon Cancer Cells Induces Transforming Growth Factor-β Response Pathway Genes

Supplementary Methods from Activin Type II Receptor Restoration in ACVR2-Deficient Colon Cancer Cells Induces Transforming Growth Factor-β Response Pathway Genes

The activin type II receptor (ACVR2) gene is a putative tumor suppressor gene that is frequently mutated in microsatellite-unstable colon cancers (MSI-H colon cancers). ACVR2 is a member of the transforming growth factor (TGF)-β type II receptor (TGFBR2) family and controls cell growth and differentiation. SMAD proteins are major intracellular effectors shared by ACVR2 and TGFBR2 signaling; however, additional shared effector mechanisms remain to be explored. To discover novel mechanisms transmitting the ACVR2 signal, we restored ACVR2 function by transfecting wild-type ACVR2 (wt-ACVR2) into a MSI-H colon cancer cell line carrying an ACVR2 frameshift mutation. The effect of ACVR2 restoration on cell growth, SMAD phosphorylation, and global molecular phenotype was then evaluated. Decreased cell growth was observed in wt-ACVR2 transfectants relative to ACVR2-deficient vector-transfected controls. Western blotting revealed higher expression of phosphorylated SMAD2 in wt-ACVR2 transfectants versus controls, suggesting cells deficient in ACVR2 had impaired SMAD signaling. Microarray-based differential expression analysis revealed substantial ACVR2-induced overexpression of genes implicated in the control of cell growth and tumorigenesis, including the activator protein (AP)-1 complex genes JUND, JUN, and FOSB, as well as the small GTPase signal transduction family members, RHOB, ARHE, and ARHGDIA. Overexpression of these genes is shared with TGFBR2 activation. This observed similarity between the activin and TGF-β signaling systems suggests that activin may serve as an alternative activator of TGF-β effectors, including SMADs, and that frameshift mutation of ACVR2 may contribute to MSI-H colon tumorigenesis via disruption of alternate TGF-β effector pathways.

Supplementary Table 2 from Activin Type II Receptor Restoration in ACVR2-Deficient Colon Cancer Cells Induces Transforming Growth Factor-β Response Pathway Genes

Supplementary Figure 1 from Activin Type II Receptor Restoration in ACVR2-Deficient Colon Cancer Cells Induces Transforming Growth Factor-β Response Pathway Genes

Patients with Barrett's esophagus (BE) are at increased risk of developing esophageal adenocarcinoma (EAC). Clinical neoplastic progression risk factors, such as age and the length of the esophageal BE segment, have been identified. However, improved molecular biomarkers predicting increased progression risk are needed for improved risk assessment and stratification. Using real-time quantitative methylation-specific PCR, we screened 10 genes (HPP1, RUNX3, RIZ1, CRBP1, 3-OST-2, APC, TIMP3, p16, MGMT, p14) for promoter hypermethylation in 77 EAC, 93 BE, and 64 normal esophagus (NE) specimens. A subset of genes manifesting significant differences in methylation frequencies between BE and EAC was then analysed in 20 dysplastic specimens. All 10 genes except p14 were frequently methylated in EACs, with RUNX3, HPP1, CRBP1, RIZ1, and OST-2 representing novel methylation targets in EAC and/or BE. p16, RUNX3, and HPP1 displayed increasing methylation frequencies in BE vs EAC. Furthermore, these increases in methylation occurred early, at the interface between BE and low-grade dysplasia (LGD). To demonstrate the silencing effect of hypermethylation, we selected the EAC cells BIC1, in which the HPP1 promoter is natively methylated, and subjected them to 5-aza-2'-deoxycytidine (Aza-C) treatment. Real-time RT-PCR indicated increased HPP1 mRNA levels after 3 days of Aza-C treatment, as well as decreased levels of methylated HPP1 DNA. Hypermethylation of a subset of six genes (APC, TIMP3, CRBP1, p16, RUNX3, and HPP1) was then tested in a retrospective longitudinal study of 99 BE and nine LGD specimens obtained from 53 BE patients undergoing surveillance endoscopy. Only high-grade dysplasia (HGD) or EAC were defined as progression end points. Two patient groups were compared: eight progressors (P) and 45 nonprogressors (NP), using Cox proportional hazards models to determine the relative progression risks of age, BE segment length, and methylation events. Multivariate analyses revealed that only hypermethylation of p16 (odds ratio (OR) 1.74, 95% confidence interval (CI) 1.33-2.20), RUNX3 (OR 1.80, 95% CI 1.08-2.81), and HPP1 (OR 1.77, 95% CI 1.06-2.81) were independently associated with an increased risk of progression, whereas age, BE segment length, and hypermethylation of TIMP3, APC, or CRBP1 were not independent risk factors. In combined analyses, risk was detectable up to, but not earlier than, 2 years preceding neoplastic progression. Hypermethylation of p16, RUNX3, and HPP1 in BE or LGD may represent independent risk factors for the progression of BE to HGD or EAC. These findings have implications regarding risk stratification, early EAC detection, and the appropriate endoscopic surveillance interval for patients with BE.

We determined the relative effects of chemical receptor inactivation on dopaminergic signaling through adenylate cyclase and phospholipase C pathways and evaluated the behavioral implications of such receptor manipulations. Groups of rats were given intraperitoneal injections of 10 mg/kg N-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline (EEDQ), a reagent that differentially inactivates neurotransmitter receptors. Control and treated animals were used to assess dopaminergic-mediated behaviors or brain tissues were prepared from the animals and used to assay D1-like receptor binding and agonist-stimulated second messenger formation. EEDQ decreased by 75% the number of D1-like binding sites and completely abolished dopamine-stimulated cyclic AMP formation in striatal membranes. Conversely, dopamine-stimulated phosphoinositide hydrolysis was insensitive to inactivation by EEDQ as examined over different durations of EEDQ treatment, in different brain regions, or with different concentrations of the D1-like receptor agonist SKF38393. EEDQ-pretreated animals lost their stereotypic response to apomorphine but showed increased vacuous jaw movements in response to apomorphine or SKF38393. Basal catalepsy was increased and SCH23390 was unable to further enhance catalepsy beyond the basal levels in the lesioned animals. In naive animals, SCH23390 catalepsy was reversed by apomorphine, and apomorphine stereotypy was reversed by SCH23390. Taken together, the present results imply that the dopamine-sensitive phospholipase C system mediates a subset of dopaminergic behaviors, notably vacuous jaw movements, in contrast to stereotypy and catalepsy which appear to be respectively mediated through stimulation and inhibition of the adenylate cyclase-coupled dopaminergic system.