D. C. Gotley

The functional roles of SNPs within the 8q24 gene desert in the cancer phenotype are not yet well understood. Here, we report that CCAT2, a novel long noncoding RNA transcript (lncRNA) encompassing the rs6983267 SNP, is highly overexpressed in microsatellite-stable colorectal cancer and promotes tumor growth, metastasis, and chromosomal instability. We demonstrate that MYC, miR-17-5p, and miR-20a are up-regulated by CCAT2 through TCF7L2-mediated transcriptional regulation. We further identify the physical interaction between CCAT2 and TCF7L2 resulting in an enhancement of WNT signaling activity. We show that CCAT2 is itself a WNT downstream target, which suggests the existence of a feedback loop. Finally, we demonstrate that the SNP status affects CCAT2 expression and the risk allele G produces more CCAT2 transcript. Our results support a new mechanism of MYC and WNT regulation by the novel lncRNA CCAT2 in colorectal cancer pathogenesis, and provide an alternative explanation of the SNP-conferred cancer risk.

In Brief Objective: We report patient outcomes from esophageal resection with respect to morbidity and cancer survival comparing open thoracotomy and laparotomy (Open), with a thoracoscopic/laparotomy approach (Thoracoscopic-Assisted) and a total thoracoscopic/laparoscopic approach (Total MIE). Methods: From a prospective database of all patients managed with cancer of the esophagus or esophagogastric junction, patients who had a resection using one of three techniques were analyzed to assess postoperative variables, adequacy of cancer clearance, and survival. Results: The number of patients for each procedure was as follows: Open, 114; Thoracoscopic-Assisted, 309; and Total MIE, 23. The groups were comparable with respect to preoperative variables. The differences in the postoperative variables were: less median blood loss in the Thoracoscopic-Assisted (400 mL) and Total MIE (300 mL) groups versus Open (600 mL); longer time for Total MIE (330 minutes) versus Thoracoscopic-Assisted (285 minutes) and Open (300 minutes); longer median time in hospital for Open (14 days) versus Thoracoscopic-Assisted (13 days), Total MIE (11 days) and less stricture formation in the Open (6.1%) versus Thoracoscopic-Assisted (21.6%), Total MIE (36%). There were no differences in lymph node retrieval for each of the approaches. Open had more stage III patients (65.8%) versus Thoracoscopic-Assisted (34.4%), Total MIE (52.1%). There was no difference in survival when the groups were compared stage for stage for overall median or 3-year survival. Conclusion: Minimally invasive techniques to resect the esophagus in patients with cancer were confirmed to be safe and comparable to an open approach with respect to postoperative recovery and cancer survival. We compared the outcomes from esophageal resection for cancer where the approaches were: an open thoracotomy and laparotomy or with minimally invasive techniques used in the thorax and abdomen. There was no major difference in morbidity, mortality, and clearance of the tumor. Cancer survival was not different for each of the approaches.

OBJECTIVE: To measure the relative risks of adenocarcinomas of the oesophagus and gastro-oesophageal junction associated with measures of obesity, and their interactions with age, sex, gastro-oesophageal reflux symptoms and smoking. DESIGN AND SETTING: Population-based case-control study in Australia. PATIENTS: Patients with adenocarcinomas of the oesophagus (n = 367) or gastro-oesophageal junction (n = 426) were compared with control participants (n = 1580) sampled from a population register. MAIN OUTCOME MEASURE: Relative risk of adenocarcinoma of the oesophagus or gastro-oesophageal junction. RESULTS: Risks of oesophageal adenocarcinoma increased monotonically with body mass index (BMI) (p(trend) <0.001). Highest risks were seen for BMI >or=40 kg/m2 (odds ratio (OR) = 6.1, 95% CI 2.7 to 13.6) compared with "healthy" BMI (18.5-24.9 kg/m2). Adjustment for gastro-oesophageal reflux and other factors modestly attenuated risks. Risks associated with obesity were substantially higher among men (OR = 2.6, 95% CI 1.8 to 3.9) than women (OR = 1.4, 95% CI 0.5 to 3.5), and among those aged <50 years (OR = 7.5, 95% CI 1.7 to 33.0) than those aged >or=50 years (OR = 2.2, 95% CI 1.5 to 3.1). Obese people with frequent symptoms of gastro-oesophageal reflux had significantly higher risks (OR = 16.5, 95% CI 8.9 to 30.6) than people with obesity but no reflux (OR = 2.2, 95% CI 1.1 to 4.3) or reflux but no obesity (OR = 5.6, 95% 2.8 to 11.3), consistent with a synergistic interaction between these factors. Similar associations, but of smaller magnitude, were seen for gastro-oesophageal junction adenocarcinomas. CONCLUSIONS: Obesity increases the risk of oesophageal adenocarcinoma independently of other factors, particularly among men. From a clinical perspective, these data suggest that patients with obesity and frequent symptoms of gastro-oesophageal reflux are at especially increased risk of adenocarcinoma.