Gene expression profile of esophageal cancer in North East India by cDNA microarray analysis

AIM： To identify alterations in genes and molecular functional pathways in esophageal cancer in a high incidence region of India where there is a widespread use of tobacco and betel quid with fermented areca nuts. METHODS： Total RNA was isolated from tumor and matched normal tissue of 16 patients with esophageal squamous cell carcinoma. Pooled tumor tissue RNA was labeled with Cy3-dUTP and pooled normal tissue RNA was labeled with Cy5-dUTP by direct labeling method. The labeled probes were hybridized with human 10K cDNA chip and expression profiles were analyzed by Genespring GX V 7.3 （Silicon Genetics）. RESULTS： Nine hundred twenty three genes were differentially expressed. Of these, 611 genes were upregulated and 312 genes were downregulated. Using stringent criteria （P ≤ 0.05 and ≥ 1.5 fold change）, 127 differentially expressed genes （87 upregulated and 40 downregulated） were identified in tumor tissue. On the basis of Gene Ontology, four different molecular functional pathways （HAPK pathway, G-protein coupled receptor family, ion transport activity, and serine or threonine kinase activity）were most significantly upregulated and six different molecular functional pathways （structural constituent of ribosome, endopeptidase inhibitor activity, structural constituent of cytoskeleton, antioxidant activity, acyl group transferase activity, eukaryotic translation elongation factor activity）were most significantly downregulated. CONCLUSION： Several genes that showed alterations in our study have also been reported from a high incidence area of esophageal cancer in China. This indicates that molecular profiles of esophageal cancer in these two different geographic locations are highly consistent.

Smoking reduction did not promote future smoking cessation in a general population

Introduction: Smoking reduction (SR) has been introduced as a strategy for smokers who are unwilling or unable to quit. We wanted to investi tigate whether SR at one-year follow-up increased the probability of abstinence from smoking at three and five-year follow-up. Methods: we included a random sample from a general population, the Inter99 study, Copenhagen, Denmark. A total of 1975 participants were daily smokers (from both the intervention and the control group) with information on tobacco consumption at both baseline and one-year follow-up (year 1999 to 2001). Of these, 112 had reduced their tobacco consumption substantially, by minimum 50%, at one-year follow-up. Information on tobacco consumption and smoking status was available on 1441 and 1308 participants at three-year and five-year follow-up, respectively. Outcome was self-reported point abstinence at three and five-year follow-up. Logistic regression analyses were adjusted for confounders. Results: One out of five smokers (20.5%) had maintained their reduced tobacco consumption at five-year follow-up. About twice as many reducers as non-reducers reported that they had tried to quit since baseline (p < 0.05). In adjusted logistic regression analyses we found no association between SR at one-year follow- up and being point abstinent at three-year (OR: 0.57;CI: 0.28 - 1.15) or five-year follow-up (OR: 1.08;CI: 0.56 - 2.09). Conclusions: Our study, including smokers from a general population found no association between substantial SR and future smoking cessation at three- and five-year follow-up. No studies so far have reported that SR undermines smoking cessation, but it is still controversial whether SR significantly increases future smoking cessation.