选择性环氧合酶-2抑制剂nimesulide对人类乳腺癌肿瘤血管形成因子的影响

目的 探讨选择性环氧合酶-2(COX-2)抑制剂nimesulide对乳腺癌肿瘤血管形成因子的影响.方法 利用体外培养的乳腺癌MDA-MB-231细胞株;应用免疫组织化学、反转录聚合酶链反应(RT-PCR)、Western blotting观察不同浓度nimesulide对肿瘤血管形成因子COX-2、PGE2、VEGF、TGFβ1表达的影响.结果 nimesulide以剂量依赖性方式下调COX-2、VEGF基因及蛋白的表达水平,同时以剂量依赖性方式抑制MDA-MB-231细胞PGE2的合成,对TGFβ1的表达无明显影响.结论 选择性COX-2抑制剂nimesulide能下调乳腺癌MDA-MB-231细胞株肿瘤血管形成因子COX-2、PGE2、VEGF的表达,为选择性COX-2抑制剂用于乳腺癌的预防及治疗提供了实验依据.     

环氧合酶-2选择性抑制剂NS-398诱导人肝癌BEL-7402细胞凋亡及其机制探讨

目的:探讨环氧合酶-2(cyclooxygenase-2,COX-2)选择性抑制剂NS-398对人肝癌BEL-7402细胞凋亡及凋亡抑制蛋白survivin、XIAP和c-IAP1表达的调节作用.方法:用不同浓度的NS-398作用BEL-7402细胞后,MTT法测定细胞增殖抑制情况,FCM法和TUNEL法检测细胞凋亡情况,免疫细胞化学法检测COX-2、survivin、XIAP和c-IAP1蛋白的表达情况.结果:NS-398 可以显著抑制BEL-7402细胞的增殖,诱导其凋亡.免疫细胞化学法检测结果显示,与未处理组相比,NS-398作用可使BEL-7402细胞中COX-2、survivin、XIAP和c-IAP1蛋白的表达明显下调(P<0.01).结论:NS-398对人肝癌细胞株BEL-7402有抑制细胞增殖和诱导细胞凋亡的作用,其机制可能与通过下调survivin、XIAP和c-IAP1的表达有关.     

NS-398对人胃癌细胞系SGC-7901增殖、凋亡和COX-2表达的影响

目的 探讨环氧合酶-2(COX-2)抑制剂NS-398对人胃癌细胞系SGC-7901增殖、凋亡及COX-2表达的影响,并进一步探讨其作用的可能机制.方法 采用四甲基偶氮唑蓝(MTT)法检测NS-398对SGC -7901细胞的杀伤抑制作用;免疫细胞化学法检测SGC-7901细胞内COX-2的蛋白表达情况;ELISA法检测NS-398作用于SGC-7901细胞后PGE2释放水平;流式细胞仪检测SGC-7901细胞的凋亡情况.结果 NS-398对胃癌SGC-7901细胞具有较强的抑制作用,且这种抑制作用随浓度和时间的增加而增强,呈剂量-时间双效应关系(P＜0.05);不同浓度NS-398作用下的SGC-7901细胞中,COX-2的表达明显减弱,且呈剂量梯度下降(P＜ 0.05);NS-398可抑制PGE2释放,并且这种抑制作用呈剂量效应关系,与对照组相比差异有统计学意义(P＜ 0.05);NS-398作用于SGC-7901细胞48 h后,细胞凋亡率升高,且呈剂量效应(P＜0.05).结论 NS-398通过COX-2依赖途径抑制SGC-7901细胞增殖并促进其凋亡.     

环氧化酶-2在人、大鼠乳腺癌及人乳腺癌细胞株的表达及其意义

 目的 探讨环氧化酶-2（COX-2）在人、大鼠乳腺癌及人乳腺癌细胞株的表达及其意义。方法 应用免疫组织化学、Western bloting、RT-PCR法检测人乳腺癌组织及配对的癌旁组织、大鼠致癌组、选择性COX-2抑制剂尼美舒利（NIM）组、人乳腺癌细胞株中COX-2的表达，MMT法检测细胞株的生长率。结果 正常人、大鼠乳腺组织不表达COX-2m RNA、蛋白，癌旁组织表达明显增高，肿瘤组织COX-2 mRNA、蛋白显著增高，NIM明显下调大鼠乳腺癌COX-2的表达；MDA-MB-231细胞COX-2呈强表达，MCF-7细胞不表达COX-2；NIM显著抑制MCF-7、MDA-MB-231细胞的增生。结论 COX-2可作为预防乳腺癌的分子靶点；NIM对MDA-MB-231细胞的抑制更为有效，提示COX-2选择性抑制剂对ER（-）的乳腺癌有更好的预防作用，COX-2的分子靶向治疗将成为乳腺癌预防和治疗的新途径。     

NS398抑制肾癌细胞增殖作用的研究

目的：探讨NS398对肾癌细胞增殖作用的影响及作用机制。方法：采用人肾癌786—0细胞系进行细胞培养，将NS398分别以25、50、100、150和200μmol／L的剂量加入细胞中，应用MTT法检测细胞增殖，流式细胞仪测定细胞凋亡。应用RT—PCR和Western blot方法检测COX-2 mRNA及其蛋白的表达。结果：NS398对肾癌786—0细胞具有较强的抑制作用，且这种抑制作用随浓度和时间的增加而增大，呈浓度依赖关系；NS398作用肾癌786—0细胞24h后，在细胞周期G0／G1期前出现明显的亚二倍体凋亡峰，随着浓度升高凋亡峰亦越来越增高，P〈0．05；RT-PCR和Western blot结果表明，不同浓度NS398作用下的肾癌786～0细胞中，COX-2 mRNA及其蛋白的表达明显减弱，且呈剂量梯度下降，P〈0．05。结论：COX-2选择性抑制剂NS398通过生长抑制、诱导调亡来抑制肾癌细胞的增殖。NS398作为活疗和预防肾癌的有效药物值得进一步深入研究。     

NS398对SGC7901胃癌细胞生长及CD44V6、MMP-9基因表达的影响

目的探讨COX-2特异性抑制剂NS398对SGC7901胃癌细胞体外生长及CD44V6、MMP-9基因表达的影响。方法体外培养SGC7901胃癌细胞,应用免疫细胞化学方法,检测SGC7901胃癌细胞中COX-2、CD44V6、MMP-9蛋白表达水平,酶联免疫吸附试验(ELISA)检测NS398对胃癌细胞PGE2分泌水平的影响,MTT法检测NS398对SGC7901胃癌细胞体外生长的抑制效应,半定量RT-PCR检测NS398作用后胃癌细胞株中CD44V6、MMP-9基因表达水平的变化。结果 SGC7901胃癌细胞中COX-2、CD44V6、MMP-9呈阳性表达,NS398可显著抑制SGC7901胃癌细胞PGE2的分泌,200μmol/L NS398抑制率达64.3%,NS398对胃癌细胞生长抑制作用呈时间及浓度依赖性;NS398作用24 h后胃癌细胞中CD44V6、MMP-9基因表达水平下降,200μmol/L NS398对CD44V6、MMP-9基因表达抑制率分别为45.7%、43.6%。结论 SGC7901胃癌细胞中COX-2、CD44V6、MMP-9呈阳性表达,NS398可有效抑制SGC7901胃癌细胞PGE2的分泌和胃癌细胞生长,并可抑制与胃癌转移相关的CD44V6、MMP-9基因的表达。     

下调Skp2表达诱导乳腺癌MCF-7细胞凋亡

目的 探讨在乳腺癌细胞系MCF-7中下调S期激酶相关蛋白(Skp2)表达诱导细胞凋亡及其机制。方法 应用RNAi方法在体外下调乳腺癌细胞系MCF-7中Skp2的表达水平,48小时后表阿霉素处理细胞,TUNEL和Hoechst 33258染色检测凋亡,Western Blot检测细胞周期调控相关因子及凋亡相关蛋白表达情况,研究其机制。结果 下调MCF-7中Skp2表达水平后,乳腺癌细胞凋亡增加。下调Skp2使p27、p21和CyclinE蛋白表达水平升高。表阿霉素处理MCF-7细胞后,Skp2蛋白水平下调。Skp2 siRNA与表阿霉素有协同诱导凋亡的作用,p53蛋白水平升高。结论 p27、p21和CyclinE在通过下调Skp2诱导的凋亡中发挥作用。Skp2 siRNA和表阿霉素协同诱导细胞凋亡,与p53依赖的凋亡途径有关。Skp2可能是乳腺癌治疗的靶点。     

VEGF上调survivin和bcl-2表达及抑制乳腺癌细胞凋亡的机制探讨

目的研究血管内皮细胞生长因子(VEGF)对乳腺癌细胞株MCF-7的凋亡及凋亡相关基因survivin和bcl-2表达的影响,探讨VEGF自分泌作用抑制肿瘤细胞凋亡的机制.方法构建VEGF165真核表达质粒,采用脂质体转染VEGF165 cDNA MCF-7细胞, 通过RT-PCR及ELISA方法鉴定转染克隆MCF-7/hVEGF165细胞中VEGF mRNA及蛋白的表达,Western blot 方法比较MCF-7/hVEGF165及MCF-7、MCF-7/pcDNA3细胞中survivin、bcl-2蛋白表达,流式细胞仪分析细胞凋亡和细胞周期.结果 MCF-7/hVEGF165细胞VEGF mRNA表达量增加,细胞培养上清中VEGF蛋白浓度为(354.50±31.93)ng/L,高于MCF-7细胞的(178.54±16.52)ng/L和MCF-7/pcDNA细胞的(190.75±13.32)ng/L(P<0.01).与MCF-7、MCF-7/pcDNA3组相比较,MCF-7/hVEGF165细胞凋亡百分数显著下降(P<0.05),分别为(2.47±0.51)% (MCF-7/hVEGF165),(7.74±1.56)%(MCF-7/pcDNA3)和(7.35±0.33)%(MCF-7);survivin和bcl-2蛋白表达增高了近3倍,但各组细胞周期变化不明显(P>0.05).结论 VEGF诱导凋亡抑制基因suvivin和bcl-2高表达,可能在自分泌VEGF抑制MCF-7凋亡中发挥重要作用.     

Nimesulide对乳腺癌细胞株化疗敏感性的影响及机制研究

目的：探讨选择性环氧化酶2（cy-clooxygenase-2，COX-2）抑制剂nimesulide对乳腺癌细胞株化疗敏感性的影响，同时探讨其可能机制。方法：利用体外培养的乳腺癌细胞株MDA-MB-231、MCF-7，MTT法比较多柔比星（ADM）及联合不同浓度的nimesulide对两种细胞抑制率的影响（IC50）；应用逆转录聚合酶链反应（RT-PCR）观察不同浓度nimesulide对两种细胞多药耐药蛋白（MDR1）mRNA的影响。结果：Nimesulide能增加ADM对MDA-MB-231、MCF-7的细胞毒作用，这种作用与nimesulide呈剂量依赖性，对COX-2高表达的MDA-MB-231细胞更加敏感；nimesulide能降低MDR1 mRNA的表达水平，并呈剂量依赖性（10、25、50μmol／L nimesulide）。结论：选择性COX-2抑制剂nimesulide能增加ADM对MDA-MB-231、MCF-7的细胞毒作用，这种作用可能与MDR1水平的下调有关，为选择性COX-2抑制剂联合细胞毒药物用于乳腺癌的化疗提供了实验依据。     

下调VEGF表达对人乳腺癌细胞凋亡相关基因影响的研究

目的:研究下调VEGF基因的表达对人乳腺癌细胞MCF-7的凋亡及相关基因表达的影响,探讨敲减VEGF后乳腺癌细胞MCF-7凋亡的机制.方法:体外化学合成针对VEGF基因的siRNA序列,在脂质体Li-pofectamine2000TM 介导下转染MCF-7细胞,RT-PCR检测VEGF、Survivin及wtP53表达水平,比色法检测Caspase-3的活性,免疫组织化学法检测Survivin蛋白的表达,并用图像分析软件分析蛋白表达强度.结果:靶向VEGF的siRNA转染MCF-7后,明显促进了细胞凋亡,VEGF mRNA表达明显减少;Survivin基因mRNA及蛋白水平表达下调(P<0.01);p53的mRNA表达上调,Caspase-3活性增高.结论:敲减VEGF基因可促进MCF-7细胞的凋亡,其主要途径可能是下调Survivin的表达,活化Caspase-3来实现.     

Premenopausal intakes of vitamins A, C, and E, folate, and carotenoids, and risk of breast cancer.

Intakes of vitamins A, C, and E, folate, and carotenoids have been hypothesized to reduce the risk of breast cancer. However, previous epidemiological studies on these nutrients and breast cancer risk have been inconclusive, and have included primarily postmenopausal women. We examined the intake of these nutrients in relation to breast cancer risk among 90,655 premenopausal women ages 26-46 years in 1991 in the Nurses' Health Study II. Nutrient intake was assessed with a validated food-frequency questionnaire at baseline in 1991 and in 1995. During 8 years of follow-up from 1991 to 1999, we documented 714 incident cases of invasive breast cancer. Overall, none of the vitamins and carotenoids was strongly related to a reduced risk of breast cancer. However, intake of vitamin A, including preformed vitamin A and carotenoids, was associated with a reduced risk of breast cancer among smokers; participants in the highest quintile of total vitamin A intake had a multivariate relative risk of 0.28 (95% confidence interval 0.12-0.62; P, test for trend <0.001; P, test for interaction <0.001) compared with those in the lowest quintile of intake. We found no evidence that higher intakes of vitamins C and E, and folate in early adult life reduce risk of breast cancer. However, intake of vitamin A may be related to a reduced risk of breast cancer among smokers.     

Intakes of fruits, vegetables, vitamins A, C, and E, and carotenoids and risk of renal cell cancer.

BACKGROUND: Fruits and vegetables rich in antioxidants have been proposed to reduce the risk of renal cell cancer. However, few prospective studies have examined the intakes of fruits, vegetables, and antioxidant vitamins in relation to the risk of renal cell cancer. METHODS: We prospectively examined the associations between the intakes of fruits, vegetables, vitamins A, C, and E, and carotenoids and risk of renal cell cancer in women and men. We followed 88,759 women in the Nurses' Health Study from 1980 to 2000, and 47,828 men in the Health Professionals Follow-up Study from 1986 to 2000. We assessed dietary intake every 2 to 4 years using a validated semiquantitative food frequency questionnaire. The Cox proportional hazards model was used to estimate study-specific multivariate relative risks (RR), which were pooled using a random effects model. RESULTS: A total of 248 (132 women and 116 men) incident renal cell cancer cases were ascertained during 2,316,525 person-years of follow-up. The consumption of fruits and vegetables was associated with a decreased risk of renal cell cancer in men (multivariate RR, 0.45; 95% CI, 0.25-0.81, for >or=6 servings of fruit and vegetable intake/d versus <3 servings/d; P test for trend = 0.02), but not in women (multivariate RR, 1.17; 95% CI, 0.66-2.07, for the same contrast; P test for trend = 0.25; P test for between-studies heterogeneity = 0.02). Intakes of vitamins A and C from food and carotenoids were inversely associated with the risk of renal cell cancer in men only, but we cannot exclude the possibility that this was due to other factors in fruit and vegetables. No clear association was observed for vitamin E in women or men. CONCLUSIONS: Fruit and vegetable consumption may reduce the risk of renal cell cancer in men.     

Occurrence,Efficacy, Metabolism,and Toxicity of Triclosan

Triclosan has broad-spectrum anti-microbial activity against most gram-negative and gram-positive bacteria. It is widely used in personal care products, household items, medical devices, and clinical settings. Due to its extensive use, there is potential for humans in all age groups to receive life-time exposures to triclosan, and, indeed, triclosan has been detected in human tissues and the environment. Data gaps exist regarding the chronic dermal toxicity and carcinogenicity of triclosan, which is needed for the risk assessment of triclosan. The US Food and Drug Administration (FDA) nominated triclosan to the National Toxicology Program (NTP) for toxicological evaluations. Currently, the NTP is conducting several dermal toxicological studies to determine the carcinogenic potential of triclosan, evaluate its endocrine and developmental-reproductive effects, and investigate the potential UV-induced dermal formation of chlorinated phenols and dioxins of triclosan. This paper reviews data on the human exposure, environmental fate, efficacy of anti-microbial activity, absorption, distribution, metabolism and elimination, endocrine disrupting effects, and toxicity of triclosan.     

Tobacco, alcohol, diet, occupation, and carcinoma of the esophagus

Information on occupation, smoking, food and beverage consumption, and medical history were compared between 275 incident cases of carcinoma of the esophagus and 275 neighborhood controls who were matched to the cases on age (within 5 years), race, and sex. Tobacco use, mainly cigarette smoking, was a significant risk factor for carcinoma of the esophagus. Ex-smokers of cigarettes showed a reduced risk relative to those who continued to smoke, and current smokers of two or more packs per day displayed a higher risk than those who smoked less. Alcohol consumption was another significant risk factor for carcinoma of the esophagus; there was a highly significant trend with average daily dose of ethanol. Relative to controls, cases also consumed significantly more fried bacon or ham, less fresh fruits and raw vegetables, and were more likely to prefer white than whole grain bread. Finally, there was a significant association between carcinoma of the esophagus and long-term occupational exposure to metal dust; this association was largely confined to the lower one-third section of the esophagus.     

Age,Race, Sex,Stage, and Incidence of Cutaneous Lymphoma

BackgroundThe incidence of the T- and B-cell CLs has been well documented, but information pertaining to racial incidence by age, and by burden of disease (stage) have not been extensively documented.Materials and MethodsThe SEER 2004-2008 public use database was investigated. The relative incidence of CL in different races and age groups was examined. Univariate and multivariate stepwise logistic regression was performed for the likelihood of presenting at a higher stage.ResultsOf 4496 patients diagnosed with CL between 2004 and 2008; 1713 patients were diagnosed with MF, 1518 with non-MF cutaneous T-cell lymphoma, and 1265 patients with cutaneous B-cell lymphoma. For MF, there was a trend for females to be less likely to present with a higher T-stage (T3-T4) than males (odds ratio [OR], 0.73) on multivariate analysis (P = .06). For race, AA had a significantly increased risk of presenting with higher T-stage (T3-T4) MF (OR, 1.72) on multivariate analysis (P = .02), compared with white patients. For white, AA, Asian/Pacific Islander, and Native American/other/unknown, the mean age at diagnosis was 59.2, 51.5, 51.3, and 53.8. These groups presented at a significantly different age than white (P = .0001, 0.0001, and 0.0006).ConclusionNonwhite racial groups present with MF at an earlier age compared with white, and AA have increased risk of presenting with higher T-stage compared with white. These findings have significant implications regarding need for earlier diagnosis and understanding the reasons for racial disparity in age and stage of presentation.     

Fat, fiber, fruits, vegetables, and risk of colorectal adenomas

A case-control study was conducted at the National Naval Medical Center (Maryland, USA) from 1994 to 1996 to investigate the possible association between dietary factors and colorectal adenomas. Cases (n = 239) were subjects diagnosed with adenomas (146 new and 93 recurrent) by sigmoidoscopy or colonoscopy. Those with no evidence of adenomas found by sigmoidoscopy were recruited as controls (n = 228). Dietary variables, assessed by a 100-item food frequency questionnaire, were analyzed by the logistic regression model, which was adjusted for age, gender and total energy intake. Variables of fat intake were further adjusted for red meat intake. An increased risk of 7% [odds ratio (OR): 1.07; 95% confidence interval (95% CI): 0.94-1.22] per 5% energy/day from total fat was observed. Every additional 5% unit of oleic acid intake/day significantly increased the adenoma risk by 115% (OR: 2.15; 95% CI: 1.05-4.39). Red meat fat increased the risk by 20% (OR: 1.20; 95% CI: 0.71-2.04), and white meat fat decreased the risk by 67% (OR: 0.33; 95% CI: 0.19-0.95) for every additional 5% unit of respective intake/day. Risk decreased by 41% (OR: 0.59; 95% CI: 0.41-0.86) for every additional 5% unit of fiber intake/day. Vegetable [OR per 100 g of vegetable intake/day: 0.83, 95% CI: 0.67-1.04] and fruit (OR per 100 g of fruit intake/day: 0.92, 95% CI: 0.82-1.03) intake showed an inverse association, and the results are suggestive of an association with the risk for adenomas. In conclusion, a strong positive association between oleic acid intake and colorectal adenoma risk was observed. This is likely to be an indicator of "unhealthy" food (meat, dairy, margarine, mayonnaise, sweet baked food) consumption in this population. Increased intake of dietary fiber was associated with a moderately decreased risk of adenomas.     

Antitumor activity of halogen analogs of phosphoramide,isophosphoramide, and triphosphoramide mustards,the cytotoxic metabolites of cyclophosphamide,ifosfamide, and trofosfamide

A series of halogen analogs of phosphoramide mustard, isophosphoramide mustard, and triphosphoramide mustard, the cytotoxic metabolites of the antitumor drugs cyclophosphamide, ifosfamide, and trofosfamide, respectively, was evaluated in vitro against human tumor cell lines and in vivo against experimental tumors to investigate the effect of replacement of chlorine with bromine or fluorine on the antitumor activity of the parent phosphoramide mustards. In the experimental tumors L1210 leukemia, B16 melanoma, mammary adenocarcinoma 16/C, and ovarian sarcoma M5076, the antitumor activity of the analogs was observed to be generally comparable with that of the parent mustards when chlorine was replaced by bromine but uniformly lower when chlorine was replaced by fluorine. Furthermore, the monobromo analog of isophosphoramide mustard displayed equal or somewhat greater activity in comparison with cyclophosphamide when evaluated against subcutaneously implanted L1210 leukemia with intraperitoneal drug treatment and against mammary adenocarcinoma 16/C.This work was financially supported by NIH, NCI grant PO1 CA34200     

Action Mechanisms of Cell-Division-Arresting Benzimidazoles and of Sterol Biosynthesis-Inhibiting Imidazoles, 1, 2, 4-Triazoles, and Pyrimidines

Summary: In spite of a formal similarity between benzimidazoles and azoles, two completely different action mechanisms are in operation, namely inhibition of tubuline association by the benzimidazoles, and inhibition of ergosterol biosynthesis at the stage of C₁₄ demethylation by imidazoles, 1, 2, 4-triazoles, and pyrimidines.
Zusammenfassung: Trotz formaler Ähnlichkeit zwischen Benzimidazolen und Azolen werden zwei vöüig verschiedene Wirkungsmechanismen verwirklicht, nämlich Hemmung der Tubulinassoziation durch Benzimidazole und Hemmung der Ergosterolbiosynthese auf der Stufe der C₁₄-Desmethylierung durch Imidazole, 1, 2, 4-Triazole und Pyrimidine.     

A comparison of general,genitourinary, bowel,and sexual quality of life among long term survivors of prostate,bladder, colorectal,and lung cancer

ObjectivesStudies of local stage prostate cancer survivors suggest that treatments carry risk of persistent impotence, incontinence, and bowel dysfunction. To examine impacts of cancer type and side effects on health-related quality of life (HRQoL) in long-term cancer survivorship, we evaluated 5-year follow-up of patients with prostate cancer and compared results with a matched group of male long-term survivors of other local-stage cancers.Materials and MethodsWe examined genitourinary, bowel and sexual symptoms, and general quality of life. Matched survivors of colorectal, lung, and bladder cancers were recruited via registries in 3 different regions in the United States. Patients were surveyed 3–5 years after diagnosis with the SF-12 and EPIC to evaluate general mental and physical health-related quality of life (HRQoL) and patient function and bother.ResultsWe analyzed responses from long-term prostate (n = 77) and bladder, colorectal, and lung cancer (n = 124) patients. In multivariate analysis, long-term local stage prostate cancer survivors had significantly higher SF-12 physical component scores but did not differ from long-term survivors of other cancers in terms of their SF-12 mental summary scores. Prostate survivors had similar mental, urinary, bowel, and sexual HRQoL compared to long-term survivors of other local stage cancers.ConclusionLong-term general and prostate-specific HRQoL was similar between local stage prostate and bladder, colorectal, and lung patients with cancer. Future research focusing on factors other than initial treatment and the cancer type per se may provide more meaningful information regarding factors that predict disparities on HRQoL among longer-term survivors of early stage male cancers.     

Consumption of alcohol,coffee, and tobacco,and gastric cancer in Spain

A case-control study on gastric cancer was carried out between 1987 and 1989 in four regions of Spain. Three hundred and fifty-four cases of histologically confirmed adenocarcinoma were included (235 men and 119 women). For each case, a control was selected, matched by sex, age, and area of residence, from the same hospital as the case. No association was observed with smoking, nor with the consumption of coffee or tea. The usual consumption of alcohol was associated with gastric cancer in men (odds ratio = 1.54, 95 percent confidence interval = 1.03–2.31), but there was no dose-response relationship. No association was observed in women. All estimations were carried out taking into account the effect of the dietary factors associated with gastric cancer. In accordance with previous evidence, the association observed between gastric cancer and alcohol appears not to be causal.Drs Agudo and González are with the Unit of Epidemiology, Hospital de Mataró, Mataró, Spain. Dr Marcos is with the Department of Preventive Medicine, Hospital Clínico, Zaragoza, Spain. Dr Sanz is with the Department of Pathology, Hospital del INSALUD, Soria, Spain. Dr Saigi is with the Department of Oncology, Hospital General de Granollers, Granollers, Spain. Dr Verge is with the Department of Surgery, Hospital de Terrassa, Terrassa, Spain. Dr Boleda is with the Department of Oncology, Hospital S. Camil, Sant Pere de Riba, Sapin. Dr Ortego is with the Department of Pathology, Hospital Clínico, Zaragoza, Spain. Address correspondence to Dr Agudo, Unit of Epidemiology, Hospital de Mataró, c. Hospital 31, 08301 Mataró, Spain. This study received financial support from the Health Research Fund (FIS) of the Spanish Ministry of Health (Financial Aid for Research exp. 87/1703, exp. 89/0018 and exp. 89/0743) and from the International Agency for Research on Cancer (Collaborative Research Agreement AEP/88/02).