MicroRNAs are small RNA species involved in biological control at multiple levels. Using genetic deletion and transgenic approaches, we show that the evolutionarily conserved microRNA-155 (miR-155) has an important role in the mammalian immune system, specifically in regulating T helper cell differentiation and the germinal center reaction to produce an optimal T cell-dependent antibody response. miR-155 exerts this control, at least in part, by regulating cytokine production. These results also suggest that individual microRNAs can exert critical control over mammalian differentiation processes in vivo.
Journal Article Recent decline of smoking in younger Italian women Get access CARLO LA VECCHIA, CARLO LA VECCHIA *Istituto di Ricerche Farmacologiche ‘Mano Negri’20157-Milan,Italy Search for other works by this author on: Oxford Academic PubMed Google Scholar EVA NEGRI, EVA NEGRI *Istituto di Ricerche Farmacologiche ‘Mano Negri’20157-Milan,Italy Search for other works by this author on: Oxford Academic PubMed Google Scholar ROMANO PAGANO ROMANO PAGANO †lstituto Ccntrale di Statistica (ISTAT)00100-Rome,Italy Search for other works by this author on: Oxford Academic PubMed Google Scholar International Journal of Epidemiology, Volume 19, Issue 1, March 1990, Page 221, https://doi.org/10.1093/ije/19.1.221 Published: 01 March 1990
Several studies have suggested an inverse association between use of combined oral contraceptives (OC) and the risk of colorectal cancer and here we present a meta-analysis of published studies. Articles considered were epidemiological studies published as full papers in English up to June 2000 that included quantitative information on OC use. The pooled relative risks (RR) of colorectal cancer for ever OC use from the 8 case-control studies was 0.81 (95% confidence interval (CI): 0.69-0.94), and the pooled estimate from the 4 cohort studies was 0.84 (95% CI: 0.72-0.97). The pooled estimate from all studies combined was 0.82 (95% CI: 0.74-0.92), without apparent heterogeneity. Duration of use was not associated with a decrease in risk, but there was some indication that the apparent protection was stronger for women who had used OCs more recently (RR = 0.46; 95% CI: 0.30-0.71). A better understanding of this potential relation may help informed choice of contraception.
The relationship between breast cancer and alcoholic beverage consumption was investigated in a case-control study of 437 women with breast cancer and 437 age-matched controls admitted to the hospital for acute conditions apparently unrelated to alcohol consumption. Compared to the relative risks (RR) for women who had never drunk alcohol, the RR for those reporting 1-3 and more than 3 alcoholic drinks per day were 1.24 and 1.93, respectively. A similar positive trend in risk with increasing daily consumption was evident for wine alone, and the point estimates were above unity for beer and spirits. Allowance for all identified potential confounding factors (including the major risk factors for breast cancer and a few selected dietary items) did not appreciably change any of the alcohol-related estimates. The RR, however, were higher at younger ages and did not rise with increasing duration of use. Nonetheless, the findings of the present study and their similarity with those of another case-control study conducted in northeastern Italy indicate that the association between alcoholic beverage consumption and breast cancer in this population is probably real, though not necessarily causal.
We reviewed epidemiological data on oral contraceptive (OC) use and colorectal, liver, lung and other nonfemale neoplasms. The data for colorectal cancer are suggestive of a favourable effect of OC, in the absence, however, of any duration-risk relation. Current, but not past, OC use is associated with excess risk of benign liver tumours, and a modest excess risk of liver cancer. The association with liver cancer was smaller for recent, low-dose OC. There was no evidence of an association between OC use and lung, digestive tract neoplasms other than colorectum, cutaneous malignant melanoma, thyroid cancer and any of the other neoplasms investigated.
Although tobacco smoking has long been recognized as a major risk factor for cancer of the upper aero-digestive tract (UADT, i.e., oral cavity, pharynx, larynx, and oesophagus), very few studies have provided estimates of the effect of very low tobacco consumption. Step-functions have been the common statistical methods for risk estimates, but the choice of reference category and of interval cutpoints influence the results, especially when data are sparse. In the present analysis, the dose-response relationship between UADT cancers and tobacco smoking was evaluated through logistic regression spline models. We included 1,241 UADT male cases and 2,835 male controls pooled from a large series of case-control studies conducted in northern Italy and in the Swiss Canton of Vaud during the last 2 decades. For cancers of the pharynx, larynx and oesophagus, the risk steadily increased with number of cigarettes/day. The risk of oral, pharyngeal and oesophageal cancers was significantly higher in smokers than in nonsmokers beginning with as low as 2 cigarettes/day. The effect of tobacco smoking at low levels seemed less evident for laryngeal cancer since the raise in risk begun with 6 cigarettes/day. In conclusion, for all the examined UADT sites, a monotonic dose-response relationship between cancer risk and cigarette smoking emerged. The excess of risk among people smoking 2 cigarettes/day highlights the absence of any harmless level for cigarette smoking, and it further supports the need of public health programs against tobacco smoking.
