Dataset Information

HBP1 promoter methylation augments the oncogenic ?-catenin to correlate with prognosis in NSCLC.

ABSTRACT: ?-catenin nuclear accumulation is frequently identified in human non-small cell lung cancer (NSCLC). The HMG-box transcription factor 1 (HBP1) is a known repressor of ?-catenin transactivation. However, the role of HBP1 in relation to ?-catenin nuclear accumulation has not been addressed in human cancer patients. In addition, the mechanism of HBP1 gene alteration in NSCLC remains unclear, although HBP1 mutation and gene deletion of HBP1 are reported in breast and colon cancers. Here, we demonstrate that HBP1 acts as a tumour suppressor and serves as a prognostic biomarker in NSCLC clinical and cell models. The immunohistochemistry data indicated that 30.5% (25/82) of tumours from NSCLC patients showed absence or low expression of HBP1 protein. A significant inverse correlation between mRNA/protein expression and promoter hypermethylation suggested that promoter hypermethylation is responsible for low expression of HBP1 in NSCLC patients. Reactivation of HBP1 expression by demethylation reagent or ectopic expression of HBP1 suppressed ?-catenin transactivation. Conversely, HBP1 knockdown increased ?-catenin transactivation. Importantly, preserved expression of HBP1 had a significantly protective effect on prognosis in patients with ?-catenin nuclear accumulation, suggesting that low expression of HBP1 in NSCLC patients with ?-catenin nuclear accumulation was one of the major determinants of prognosis. Our data from cellular and clinical models suggest that HBP1 is a suppressor of cancer progression, making it a potential prognostic predictor and therapeutic target to attenuate lung cancer progression.

SUBMITTER: Tseng RC

PROVIDER: S-EPMC4196651 | biostudies-literature | 2014 Sep

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

HBP1 promoter methylation augments the oncogenic β-catenin to correlate with prognosis in NSCLC.

Tseng Ruo-Chia RC Huang Way-Ren WR Lin Su-Feng SF Wu Pei-Chen PC Hsu Han-Shui HS Wang Yi-Ching YC

Journal of cellular and molecular medicine 20140604 9

β-catenin nuclear accumulation is frequently identified in human non-small cell lung cancer (NSCLC). The HMG-box transcription factor 1 (HBP1) is a known repressor of β-catenin transactivation. However, the role of HBP1 in relation to β-catenin nuclear accumulation has not been addressed in human cancer patients. In addition, the mechanism of HBP1 gene alteration in NSCLC remains unclear, although HBP1 mutation and gene deletion of HBP1 are reported in breast and colon cancers. Here, we demonstr ...[more]

PMID: 24895061

Similar Datasets

Project description:β-Catenin plays dual role in adhesion complex formation and the Wnt signaling pathway. Although β-catenin expression appears to be upregulated and Wnt signaling pathway is activated in the majority of cancers, its expression level seems to be lost in non-small cell lung cancer (NSCLC). We previously reported that the promoter of β-catenin was hypermethylated in two NSCLC cell lines. In the current study, we expanded our analysis for the methylation status of β-catenin promoter region and its protein expression in seven NSCLC cell lines and a series of 143 cases of primary human lung cancer with adjacent non-neoplastic tissues. Quantitative methylation specific PCR (qMSP) analysis showed methylation of β-catenin promoter region in five NSCLC cell lines, with increased β-catenin protein levels upon 5'-Aza-2'-deoxycytidine (5-aza-dC) treatment. The methylation status in SPC (methylated) and A549 (unmethylated) was confirmed by bisulfite sequencing PCR. 5-Aza-dC treatment inhibited invasiveness of SPC but not A549. Immunofluorescence analysis showed membranous β-catenin expression was lost in SPC and could be re-established by 5-aza-dC, while Wnt3a treatment led to nuclear translocation of β-catenin in both SPC and A549. Dual-luciferase assays indicated that 5-aza-dC treatment caused no significant increase in Wnt signaling activity compared with Wnt3a treatment. The effect of demethylation agent in SPC can be reversed by β-catenin depletion but not E-cadherin depletion which indicated that the methylation mediated β-catenin silencing might enhance NSCLC invasion and metastasis in an E-cadherin independent manner. Subsequent immunohistochemistry results further confirmed that β-catenin promoter hypermethylation correlated with loss of immunoreactive protein expression, positive lymph node metastasis, high TNM stage and poor prognosis. The present study implicates β-catenin promoter hypermethylation in the mechanism of epigenetic changes underlying NSCLC metastasis and progression, thus indicating the potential of β-catenin as a novel epigenetic target for the treatment of NSCLC patients.

Project description:Genome-wide association studies have highlighted three major lung cancer susceptibility regions at 15q25.1, 5p15.33 and 6p21.33. To gain insight into the possible mechanistic relevance of the genes in these regions, we investigated the regulation of candidate susceptibility gene expression by epigenetic alterations in healthy and lung tumor tissues. For genes up or downregulated in lung tumors, the influence of genetic variants on DNA methylation was investigated and in vitro studies were performed. We analyzed 394 CpG units within 19 CpG islands in the susceptibility regions in a screening set of 34 patients. Significant findings were validated in an independent patient set (n=50) with available DNA and RNA. The most consistent overall DNA methylation difference between tumor and adjacent normal tissue on 15q25 was tumor hypomethylation in the promoter region of CHRNB4 with a median difference of 8% (P<0.001), which resulted in overexpression of the transcript in tumors (P<0.001). Confirming previous studies, we also found hypermethylation in CHRNA3 and telomerase reverse transcriptase (TERT) with significant expression changes. Decitabine treatment of H1299 cells resulted in reduced methylation levels in gene promoters, elevated transcript levels of CHRNB4 and CHRNA3, and a slight downregulation of TERT demonstrating epigenetic regulation of lung cancer cells. Single-nucleotide polymorphisms rs421629 on 5p15.33 and rs1948, rs660652, rs8040868 and rs2036527 on 15q25.1, previously identified as lung cancer risk or nicotine-addiction modifiers, were associated with tumor DNA methylation levels in the promoters of TERT and CHRNB4 (P<0.001), respectively, in two independent sample sets (n=82; n=150). In addition, CHRNB4 knockdown in two different cell lines (A549 and H1299) resulted in reduced proliferation (PA549<0.05;PH1299<0.001) and propensity to form colonies in H1299 cells. These results suggest epigenetic deregulation of nicotinic acetylcholine receptor subunit (nAChR) genes which in the case of CHRNB4 is strongly associated with genetic lung cancer susceptibility variants and a functional impact on tumorigenic potential.

Project description:Claudin?3 expression is associated with gastric cancer progression, but the role of epigenetic modifications remains unclear. We investigated methylation of the claudin?3 promoter and expression profiles in gastric adenocarcinoma and their associations with clinicopathological characteristics and prognosis of the patients. A total of 122 patients with advanced gastric cancer [stage IIB?IV, with lymph node (LN) metastasis] were enrolled. Each patient provided 4 tissue samples: normal gastric epithelium, intestinal metaplasia, primary tumor and metastatic LN. Claudin?3 protein expression was examined by immunohistochemistry. Claudin?3 promoter methylation was determined by methylation?specific PCR and verified by bisulfite sequencing PCR. Claudin?3 mRNA expression was measured by real?time PCR in a subset of cases, and its correlation with protein expression was analyzed using Spearman correlation. Kaplan?Meier survival analysis was performed (log?rank test). Factors associated with survival were identified by Cox regression. The strong expression rate of claudin?3 in intestinal metaplasia, primary tumor, metastatic LN and normal gastric epithelium was 91.8, 58.2, 30.3 and 13.9%, respectively. The promoter hypermethylation rate in intestinal metaplasia, primary tumor, normal gastric epithelium and metastatic LN was 5.7, 27.9, 36.9 and 49.2%, respectively. Claudin?3 mRNA and protein expression were positively correlated (P<0.001) with normal gastric epithelium (rs=0.745), intestinal metaplasia (rs=0.876), primary gastric adenocarcinoma (rs=0.915) and metastatic LN (rs=0.819). Claudin?3 mRNA expression was negatively correlated with claudin?3 promoter methylation. Median patient survival was 38, 22 and 11 months in the hypomethylated, partially methylated and hypermethylated groups, respectively (P<0.001). Claudin?3 promoter methylation status (HR: 5.67; 95% CI: 2.27?14.17) but not claudin?3 expression was an independent predictor of survival. Claudin?3 promoter hypermethylation reduces claudin?3 expression and independently predicts poor prognosis.

Dataset Information

HBP1 promoter methylation augments the oncogenic ?-catenin to correlate with prognosis in NSCLC.

Publications

HBP1 promoter methylation augments the oncogenic β-catenin to correlate with prognosis in NSCLC.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure