The unfolded protein response is activated in Helicobacter-induced gastric carcinogenesis in a non-cell autonomous manner.

Mucous metaplasia (MM) is an aberrant secretory phenotype that arises during Helicobacter-induced gastric carcinogenesis. HSPA5, a key modulator of the unfolded protein response (UPR) activated by endoplasmic reticulum (ER) stress is overexpressed in gastric cancer (GC). We studied activation of the UPR in MM and GC in humans and mice.

Comprehensive profiling of DNA methylation in colorectal cancer reveals subgroups with distinct clinicopathological and molecular features.

Background: Most previous studies of the CpG island methylator phenotype (CIMP) in colorectal cancer (CRC) have been conducted on a relatively small numbers of CpG sites. In the present study we performed comprehensive DNA methylation profiling of CRC with the aim of characterizing CIMP subgroups.

Methods: DNA methylation at 1,505 CpG sites in 807 cancer-related genes was evaluated using the Illumina GoldenGate methylation array in 28 normal colonic mucosa and 91 consecutive CRC samples.

BRAF mutation is associated with the CpG island methylator phenotype in colorectal cancer from young patients.

This study investigated the relationship between BRAF mutation, the CpG island methylator phenotype (CIMP+) and APC methylation in colorectal cancer (CRC) from young patients. The V600E BRAF mutation was found in 7% of cases and was strongly associated with the tumour features of proximal site, advanced stage and poor histological grade. More than half (53%) the tumours with BRAF mutation were also CIMP+ as evaluated by a standard panel of markers, compared to only 4% of tumours with wildtype BRAF (P<0.

An improved quality control for bisulfite-PCR-based DNA methylation analysis: cycle threshold value.

Background: The diagnostic potential of DNA methylation has generated a need for quality control systems in its analysis. Here, we tested whether cycle threshold (Ct) values from real-time quantitative PCR correlate better with the reliability of bisulfite-PCR methylation analyses than spectrophotometric concentrations.

Methods: A total of 18 cell line DNA samples were quantified for beta-actin (ACTB) Ct and spectrophotometric values from 1-microL volumes.

Detection of BRAF V600E mutation by pyrosequencing.

Introduction: Detection of the V600E hotspot mutation in BRAF oncogene is extremely useful for the screening of hereditary non-polyposis colorectal cancer (Lynch's syndrome) and for the prediction of sensitivity to MEK inhibitors. Here we describe a method for detecting this mutation based upon pyrosequencing technology.

Methods: The efficiency of pyrosequencing for detecting BRAF V600E mutations was compared with the conventional dideoxy sequencing method in 12 tumour cell lines and in 108 colorectal tumours.