Altered JS‐2 expression in colorectal cancers and its clinical pathological relevance

Abstract

Mucinous Adenocarcinoma Adenoma JS-2 gene A B S T R A C TJS-2 is a novel gene located at 5p15.2 and originally detected in primary oesophageal cancer.There is no study on the role of JS-2 in colorectal cancer. The aim of this study is to determine the gene copy number and expression of JS-2 in a large cohort of patients with colorectal tumours and correlate these to the clinicopathological features of the cancer patients. We evaluated the DNA copy number and mRNA expression of JS-2 in 176 colorectal tissues (116 adenocarcinomas, 30 adenomas and 30 non-neoplastic tissues) using real-time polymerase chain reaction. JS-2 expression was also evaluated in two colorectal cancer cell lines and a benign colorectal cell line. JS-2 amplification was noted in 35% of the colorectal adenocarcinomas. Significant differences in relative expression levels for JS-2 mRNA between different colorectal tissues were noted ( p ¼ 0.05). Distal colorectal adenocarcinoma had significantly higher copy number than proximal adenocarcinoma ( p ¼ 0.005). The relative expression level of JS-2 was different between colonic and rectal adenocarcinoma ( p ¼ 0.007).Mucinous adenocarcinoma showed higher JS-2 expression than non-mucinous adenocarcinoma ( p ¼ 0.02). Early T-stage cancers appear to have higher JS-2 copy number and lower expression of JS-2 mRNA than later stage cancers ( p ¼ 0.001 and 0.03 respectively). Colorectal cancer cell lines showed lower expression of JS-2 than the benign colorectal cell line. JS-2 copy number change and expression were shown for the first time to be altered in the carcinogenesis of colorectal cancer. In addition, genetic alteration of JS-2 was found to be related to location, pathological subtypes and staging of colorectal cancer.

Regulation of microRNA‐1288 in colorectal cancer: Altered expression and its clinicopathological significance

“…Inverse ratio of miR1288 versus RNU6B (control miRNA) [expression ratio] was used to represent the miRNA expression levels in different colorectal tissues and cell lines. Final evaluation of miR‐1288 expression levels were analyzed as in our previous study . A fold change of more than 1.5 was considered as high miR‐1288 expression.…”

Somatic gene copy number alterations in colorectal cancer: new quest for cancer drivers and biomarkers

“…102 . Interestingly, early T-stage cancers seemed to have higher JS-2 copy number and lower expression of JS-2 mRNA than later stage cancers, suggesting the complicity of JS-2 regulation in CRC.…”

Gene amplified in oesophageal cancer 1 (GAEC1)amplification in colorectal cancers and its impact on patient's survival

“…Culturing conditions for these cell lines were as published previously 4. Tissues were collected from 283 patients (213 Australian; 70 Japanese) diagnosed with colorectal cancers.…”

“…Actuarial survival rates of patients were calculated from the date of surgical resection of the colorectal cancers to the date of death or last follow-up. DNA extraction and PCR reactions for GAEC1 copy number were performed as in our previous studies 3 4. A ΔCt of <−1 was considered as gain of GAEC1 copies, Ct value >1 was considered as reduced GAEC1 copies and a Ct between these ranges was defined as normal/no change in GAEC1 copies.…”