膳食模式与肿瘤的关系及作用机制

膳食与肿瘤的关系密切,健康的膳食模式可降低某些肿瘤的发病风险,而不恰当的膳食结构则可能是机体发生全 身性代谢性疾病的重要诱因,比如肿瘤。 近年来,越来越多的研究探索了不同饮食模式对肿瘤的发病率、死亡率以及治疗效 果的影响,本文梳理了目前备受关注的几种饮食模式,包括地中海饮食、生酮饮食及促炎饮食与肿瘤的关系及可能的作用机 制,结果表明地中海饮食可通过调节激素水平、激活抗氧化机制、刺激免疫系统、下调致癌因子水平等方式降低如结直肠癌、 前列腺癌、呼吸和消化系统癌、乳腺癌、口咽癌(口腔癌和咽喉癌)等的发生率以及总体死亡率,生酮饮食模式则可能通过靶向 调节糖代谢、氨基酸代谢、线粒体代谢以及调控基因表达、调节信号通路、降低血管化水平等途径减缓肿瘤生长,在延长患者 的生存期以及逆转肿瘤诱导恶液质进程等方面发挥着重要作用,并逐渐成为一种有效的抗癌治疗手段,而促炎饮食因其膳食 中含有较多的炎症成分,则可能通过增加机体炎症水平、改变微生物群状态、影响表观遗传重塑等方式促进肿瘤的发生和 发展。     

Cancer incidence in British vegetarians

Background:

Few prospective studies have examined cancer incidence among vegetarians.

Methods:

We studied 61 566 British men and women, comprising 32 403 meat eaters, 8562 non-meat eaters who did eat fish (‘fish eaters'') and 20 601 vegetarians. After an average follow-up of 12.2 years, there were 3350 incident cancers of which 2204 were among meat eaters, 317 among fish eaters and 829 among vegetarians. Relative risks (RRs) were estimated by Cox regression, stratified by sex and recruitment protocol and adjusted for age, smoking, alcohol, body mass index, physical activity level and, for women only, parity and oral contraceptive use.

Results:

There was significant heterogeneity in cancer risk between groups for the following four cancer sites: stomach cancer, RRs (compared with meat eaters) of 0.29 (95% CI: 0.07–1.20) in fish eaters and 0.36 (0.16–0.78) in vegetarians, P for heterogeneity=0.007; ovarian cancer, RRs of 0.37 (0.18–0.77) in fish eaters and 0.69 (0.45–1.07) in vegetarians, P for heterogeneity=0.007; bladder cancer, RRs of 0.81 (0.36–1.81) in fish eaters and 0.47 (0.25–0.89) in vegetarians, P for heterogeneity=0.05; and cancers of the lymphatic and haematopoietic tissues, RRs of 0.85 (0.56–1.29) in fish eaters and 0.55 (0.39–0.78) in vegetarians, P for heterogeneity=0.002. The RRs for all malignant neoplasms were 0.82 (0.73–0.93) in fish eaters and 0.88 (0.81–0.96) in vegetarians (P for heterogeneity=0.001).

Conclusion:

The incidence of some cancers may be lower in fish eaters and vegetarians than in meat eaters.     

Adherence to the MIND Diet and Risk of Breast Cancer: A Case-control Study

IntroductionNo data are available on the association between adherence to the Mediterranean-DASH Intervention for Neurodegenerative Delay (MIND) diet and breast cancer.Materials and MethodsThis population-based case-control study was conducted among women aged ≥ 30 years, who were residing in Isfahan, Iran. The study included 350 patients with newly diagnosed stage I to IV breast cancer, for whom in situ or invasive status of breast cancer was confirmed by physical examination, mammography, and pathologic verification. Controls were 700 age-matched apparently healthy individuals who were randomly selected from the general population. Dietary data were collected using a validated 106-item Willett-format, semi-quantitative dish-based food frequency questionnaire.ResultsAfter adjustment for age and energy intake, women in the top tertile of the MIND diet score had 60% lower odds of breast cancer than women in the bottom tertile (odds ratio [OR], 0.40; 95% confidence interval [CI], 0.29-0.55). In the fully adjusted model including body mass index, those with the greatest MIND diet scores had 50% lower chance of breast cancer (OR, 0.50; 95% CI, 0.34-0.72) than those with the lowest adherence to the MIND diet. Postmenopausal women with the greatest adherence to the MIND diet were less likely to have breast cancer than those in the bottom tertile (OR, 0.45; 95% CI, 0.30-0.66). In addition, we found a significant inverse association between adherence to the MIND diet and odds of breast cancer among normal-weight women (OR, 0.39; 95% CI, 0.25-0.60).ConclusionAdherence to the MIND diet was associated with a reduced chance of breast cancer in this case-control study.     

Prediagnosis dietary pattern and survival in patients with multiple myeloma

Inflammation and endogenous growth factors are important in multiple myeloma (MM) pathogenesis. Although diets that modulate these biologic pathways may influence MM patient survival, studies have not examined the association of dietary patterns with MM survival. We conducted pooled prospective survival analyses of 423 MM patients from the Nurses' Health Study (1986–2016) and the Health Professionals Follow-up Study (1988–2016) using Cox regression models. We used data from repeated food frequency questionnaires (FFQ) to compute dietary patterns as of the last prediagnosis FFQ, including the Alternate Healthy Eating Index (AHEI)-2010, alternate Mediterranean Diet, Dietary Approaches to Stop Hypertension, Prudent, Western and empirical dietary inflammatory patterns and empirical dietary indices for insulin resistance and hyperinsulinemia. During follow-up, we documented 295 MM-related deaths among 345 total deaths. MM-specific mortality was 15–24% lower per one standard deviation (SD) increase (e.g., toward healthier habits) in favorable dietary pattern scores. For example, the multivariable-adjusted hazard ratio [HR] and 95% confidence interval [CI] per 1-SD increase in AHEI-2010 score were 0.76, 0.67–0.87 (p < 0.001). In contrast, MM-specific mortality was 16–24% higher per 1-SD increase (e.g., toward less healthy habits) in “unhealthy” diet scores; for example, the multivariable-adjusted HR, 95% CI per 1-SD increase in Western pattern score were 1.24, 1.07–1.44 (p = 0.005). Associations were similar for all-cause mortality. In conclusion, our consistent findings for multiple dietary patterns provide the first evidence that MM patients with healthier prediagnosis dietary habits may have longer survival than those with less healthy diets.     

Diet diversity, diet composition, and risk of colon cancer (United States)

In this study, we evaluate diet diversity, diet composition, and risk of colon cancer in an incident population-based study of 1,993 cases and2,410 controls in the Kaiser Permanente Medical Care Program of Northern California, eight counties in Utah, and the Twin Cities area of Minnesota(United States). Ninety-one and one-half percent of the population were non-Hispanic White. Dietary intake was obtained using an adaptation of the CARDIA diet-history questionnaire. Diet diversity was defined as the number of unique food items reported; diversity also was explored within six major food groups. Composition of the diet was described by estimating the proportion of total number of food items contributed by major food groups. Younger individuals, higher educated individuals, and those who lived in larger households reported eating the most diverse diet. Total diet diversity was not associated with colon cancer. However, eating a diet with greater diversity of meats, poultry, fish, and eggs, was associated with a50 percent increase in risk among all men (95 percent confidence interval[CI] = 1.1-2.0; P trend = 0.01), with slightly stronger associations for younger men and men with distal tumors. A diet with a greater number of refined grain products also was associated with increased risk among men(odds ratio [OR] = 1.7, CI = 1.3-2.3). Women who ate a diet with a more diverse pattern of vegetables were at approximately a 20 percent lower risk than women who had the least diverse diet in vegetables. Assessment of diet composition showed that men who consumed a large proportion of their food items from meat, fish, poultry, and eggs were at an increased risk, with the most marked association being for distal tumors (OR = 1.7, CI = 1.2-2.5).Women who consumed the largest percentage of their food items in the form of plant foods (fruits, vegetables, or whole grains) were at a reduced risk of developing colon cancer (OR = 0.7, CI = 0.5-1.0). This revised version was published online in July 2006 with corrections to the Cover Date.     

Meta‐analysis of the association between dietary inflammatory index (DII) and cancer outcomes

Proinflammatory dietary patterns have been associated with increased cancer risk and mortality. We present a systematic review and meta‐analysis of the current published literature on a dietary inflammatory index (DII) score and its association with cancer risk and mortality outcomes. Published articles from online databases (PubMed, Scopus, and Embase) examining the association between DII and any cancer risk, incidence, or mortality between 1980 and November 2016 were selected for review. Results of studies meeting inclusion criteria were summarized and meta‐analyzed using STATA to generate summary measures of association across studies. Sixty‐three published articles were identified from the search, and following title, abstract and full‐text review, twenty‐four studies met inclusion criteria. All articles calculated DII scores based on study‐specific food‐frequency questionnaires using methodology from the same article. Of the 24 included studies, 13 were case–control, 6 were prospective cohort, 1 was a retrospective cohort, 3 were RCTs, and 1 did not specify study design. The most common cancers examined were colorectal, breast, lung, and prostate. Individuals in the highest versus lowest DII categories had 25% increased risk of overall cancer incidence (RR: 1.25, 95% CI: 1.16–1.35), 75% higher odds of cancer (OR: 1.75, 95% CI: 1.43–2.16) and 67% increased risk of cancer mortality (RR: 1.67, 95% CI: 1.13–2.48). Upon stratification for cancer type, positive associations remained (RR_breast: RR: 1.12, 95% CI: 1.03–1.22) (RR_colorectal: 1.33, 95% CI: 1.22–1.46) (RR_lung: 1.30, 95% CI: 1.13–1.50). There were consistent and significant positive associations between higher DII and cancer incidence and mortality across cancer types, study populations, and study design.     

Antioxidant intake and risk of endometrial cancer: Results from the Nurses' Health Study

To investigate the associations between antioxidant intake and risk of endometrial cancer, the authors analyzed data from the prospective Nurses' Health Study. From 1980 to 2006, 669 invasive adenocarcinoma cases were identified over 1.3 million person‐years of follow‐up. Information on dietary intake was collected in 1980 and updated every 2–4 years. Cox proportional hazard models were used to calculate the multivariate relative risks (RR), controlling for total energy and potential risk factors for endometrial cancer. Overall, the authors found no association between intakes of vitamins A, C, E or carotenoids from foods or supplements and cancer risk. The RR and 95% confidence intervals (CI) for the highest vs. lowest quintiles of vitamins A, C, E and total carotenoids were 1.09 (95% CI: 0.85–1.39), 0.98 (95% CI: 0.76–1.25), 1.07 (95% CI: 0.83–1.38) and 1.12 (95% CI: 0.86–1.45), respectively. Similarly, the use of multivitamins or specific vitamins A, C or E supplements was unassociated with risk. In subgroup analyses, several associations seemed to vary by postmenopausal hormone use. Our results suggest that there is no overall association between dietary antioxidant intake or use of antioxidant supplements with risk of endometrial cancer.     

Dietary acrylamide and risk of prostate cancer

Acrylamide has been designated by IARC as a "probable human carcinogen." High levels are formed during cooking of many commonly consumed foods including French fries, potato chips, breakfast cereal and coffee. Two prospective cohort studies and two case-control studies in Europe found no association between acrylamide intake and prostate cancer. We examined this association in a large prospective cohort of 47,896 US men in the Health Professionals' Follow-up Study, using updated dietary acrylamide intake from food frequency questionnaires in 1986, 1990, 1994, 1998 and 2002. From 1986 through 2006, we documented 5025 cases of prostate cancer, and 642 lethal cancers. We used Cox proportional hazards models to assess the association between acrylamide intake from diet and prostate cancer risk overall as well as risk of advanced or lethal cancer. Acrylamide intake ranged from a mean of 10.5 mcg/day in the lowest quintile to 40.1 mcg/day in the highest quintile; coffee and potato products were largest contributors to intake. The multivariate-adjusted relative risk of prostate cancer was 1.02 (95% confidence interval: 0.92-1.13) for the highest versus lowest quintile of acrylamide intake (p-value for trend = 0.90). Results were similar when restricted to never smokers and to men who had prostate-specific antigen (PSA) tests. There was no significant association for dietary acrylamide and risk of lethal, advanced or high-grade disease, or for different latency periods ranging from 0-4 years to 12-16 years. We found no evidence that acrylamide intake, within the range of US diets, is associated with increased risk of prostate cancer.     

Adolescent diet and risk of breast cancer

OBJECTIVES: To investigate the components of adolescent diet that may influence risk of breast cancer as an adult. METHODS: Retrospective cohort study among 47,355 participants in the Nurses Health Study II who answered a 131-item food frequency questionnaire about diet during high school. Cox proportional hazards regression was used to estimate relative risks and 95% confidence intervals among incident cases of breast cancer between 1989 (inception of the study) and 1998 (when high school diet was assessed). RESULTS: Intakes of fat and fiber were not significantly related to risk of breast cancer in multivariate analysis, but increased intake of vegetable fat ( Q (5) versus Q (1) multivariate RR = 0.58, 95% CI (0.38-0.86); test for trend p = 0.005) and vitamin E ( Q (5) versus Q (1) multivariate RR = 0.61, 95% CI (0.42-0.89); test for trend p = 0.003) were associated with a lower risk. A higher dietary glycemic index ( Q (5) versus Q (1) multivariate RR = 1.47, 95% CI (1.04-2.08); test for trend p = 0.01) was associated with increased risk of breast cancer. CONCLUSIONS: The apparent protective effects of vegetable fat and vitamin E and adverse effect of high glycemic foods on risk of breast cancer need confirmation in prospective analyses.     

A multicenter case–control study of diet and lung cancer among non-smokers

Objective: We have examined the role of dietary patterns and specific dietary nutrients in the etiology of lung cancer among non-smokers using a multicenter case–control study.Methods: 506 non-smoking incident lung cancer cases were identified in the eight centers along with 1045 non-smoking controls. Dietary habits were assessed using a quantitative food-frequency questionnaire administered by personal interview. Based on this information, measures of total carotenoids, beta-carotene and retinol nutrient intake were estimated.Results: Protective effects against lung cancer were observed for high consumption of tomatoes, (odds ratio (OR) = 0.5; 95% confidence interval (CI) 0.4–0.6), lettuce (OR = 0.6; 95% CI 0.3–1.2), carrots (OR = 0.8; 95% CI 0.5–1.1), margarine (OR = 0.7; 95% CI 0.5–0.8) and cheese (OR = 0.7; 95% CI 0.5–1.0). Only weak protective effects were observed for high consumption of all carotenoids (OR = 0.8; 95% CI 0.6–1.0), beta-carotene (OR=0.8; 95% CI 0.6–1.1) and retinol (OR = 0.9; 95% CI 0.7–1.1). Protective effects for high levels of fruit consumption were restricted to squamous cell carcinoma (OR = 0.7; 95% CI 0.4–1.2) and small cell carcinoma (OR = 0.7; 95% CI 0.4–1.2), and were not apparent for adenocarcinoma (OR = 0.9; 95% CI 0.6–1.3). Similarly, any excess risk associated with meat, butter and egg consumption was restricted to squamous and small cell carcinomas, but was not detected for adenocarcinomas.Conclusions: This evidence suggests that the public health significance of increasing vegetable consumption among the bottom third of the population would include a reduction in the incidence of lung cancer among lifetime non-smokers by at least 25%, and possibly more. A similar protective effect for increased fruit consumption may be present for squamous cell and small cell lung carcinomas.     

Dietary intake of meat, fruits, vegetables, and selective micronutrients and risk of bladder cancer in the New England region of the United States

Background:

Despite many studies on diet and bladder cancer, there are areas that remain unexplored including meat mutagens, specific vegetable groups, and vitamins from diet.

Methods:

We conducted a population-based case–control study of bladder cancer in Maine, New Hampshire, and Vermont. A total of 1171 cases were ascertained through hospital pathology records and cancer registries from 2001 to 2004. Overall, 1418 controls were identified from the Department of Motor Vehicles (<65 years) and Center for Medicaid and Medicare Services (65–79 years) and were frequency-matched to cases by state, sex, and age (within 5 years). Diet was assessed with a self-administered Diet History Questionnaire. Unconditional logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (CI).

Results:

Processed meat intake was positively associated with bladder cancer (highest vs lowest quartile OR: 1.28; 95% CI: 1.00–1.65; P_trend=0.035), with a stronger association for processed red meat (OR: 1.41; 95% CI: 1.08–1.84; P_trend=0.024). There were no associations between intake of fruits or vegetables and bladder cancer. We did, however, observe an inverse association with vitamin B12 intake (OR: 0.77; 95% CI: 0.61–0.99; P=0.019).

Conclusion:

Vitamin B12 from diet may be protective against bladder cancer, whereas consuming processed meat may increase risk.     

Acrylamide exposure measured by food frequency questionnaire and hemoglobin adduct levels and prostate cancer risk in the Cancer of the Prostate in Sweden Study

Acrylamide, a probable human carcinogen, is formed during the cooking of many commonly consumed foods. Data are scant on whether dietary acrylamide represents an important cancer risk in humans. We studied the association between acrylamide and prostate cancer risk using 2 measures of acrylamide exposure: intake from a food frequency questionnaire (FFQ) and acrylamide adducts to hemoglobin. We also studied the correlation between these 2 exposure measures. We used data from the population‐based case‐control study Cancer of the Prostate in Sweden (CAPS). Dietary data was available for 1,499 cases and 1,118 controls. Hemoglobin adducts of acrylamide were measured in blood samples from a subset of 170 cases and 161 controls. We calculated odds ratios (ORs) for the risk of prostate cancer in high versus low quantiles of acrylamide exposure using logistic regression. The correlation between FFQ acrylamide intake and acrylamide adducts in non‐smokers was 0.25 (95% confidence interval: 0.14–0.35), adjusted for age, region, energy intake, and laboratory batch. Among controls the correlation was 0.35 (95% CI: 0.21–0.48); among cases it was 0.15 (95% CI: 0.00–0.30). The OR of prostate cancer for the highest versus lowest quartile of acrylamide adducts was 0.93 (95% CI: 0.47–1.85, p‐value for trend = 0.98). For FFQ acrylamide, the OR of prostate cancer for the highest versus lowest quintile was 0.97 (95% CI: 0.75–1.27, p trend = 0.67). No significant associations were found between acrylamide exposure and risk of prostate cancer by stage, grade, or PSA level. Acrylamide adducts to hemoglobin and FFQ‐measured acrylamide intake were moderately correlated. Neither measure of acrylamide exposure—hemoglobin adducts or FFQ—was associated with risk of prostate cancer. © 2008 Wiley‐Liss, Inc.     

The relationship between diet and breast cancer in men (United States)

OBJECTIVES: The purpose of this paper was to investigate the relationship between food and beverage consumption and the development of breast cancer in men. METHODS: Possible relationships of dietary factors to risk of breast cancer in men were assessed in a case-control study conducted between 1983 and 1986. Cases (N = 220) were ascertained from ten population-based cancer registries. Controls (N = 291) were selected by random-digit dialing (< age 65) and from Health Care Financing Administration Medicare beneficiary lists (> or = age 65). RESULTS: No trends in risk were observed with increasing intakes of specific foods, except for an increase in risk with citrus fruits. No increase in risk with increasing amounts of specific fats, vitamins, or minerals or with amounts of protein, fiber, carbohydrate, starches, nitrites, or alcohol consumed was observed, except for an increase in risk with dietary vitamin C consumption. A decreasing trend in risk with dietary niacin and with coffee and an increasing trend in risk with tea consumption were observed. No associations were found with use of any dietary supplements, including vitamin C. CONCLUSIONS: The observed associations are not consistent with findings from studies of breast cancer in women and probably do not represent causal relationships. Dietary factors are unlikely to be strong determinants of breast cancer in men.     

Dietary influences on survival after ovarian cancer

We evaluated the effects of various food groups and micronutrients in the diet on survival among women who originally participated in a population-based case-control study of ovarian cancer conducted across 3 Australian states between 1990 and 1993. This analysis included 609 women with invasive epithelial ovarian cancer, primarily because there was negligible mortality in women with borderline tumors. The women's usual diet was assessed using a validated food frequency questionnaire. Deaths in the cohort were identified using state-based cancer registries and the Australian National Death Index (NDI). Crude 5-year survival probabilities were estimated using the Kaplan-Meier technique, and adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) were obtained from Cox regression models. After adjusting for important confounding factors, a survival advantage was observed for those who reported higher intake of vegetables in general (HR = 0.75, 95% CI = 0.57-0.99, p-value trend 0.01 for the highest third, compared to the lowest third), and cruciferous vegetables in particular (HR = 0.75, 95% CI = 0.57-0.98, p-value trend 0.03), and among women in the upper third of intake of vitamin E (HR = 0.76, 95% CI = 0.58-1.01, p-value trend 0.04). Inverse associations were also seen with protein (p-value trend 0.09), red meat (p-value trend 0.06) and white meat (p-value trend 0.07), and modest positive trends (maximum 30% excess) with lactose (p-value trend 0.04), calcium and dairy products. Although much remains to be learned about the influence of nutritional factors after a diagnosis of ovarian cancer, our study suggests the possibility that a diet high in vegetable intake may help improve survival.     

A cohort study of dietary carotenoids and lung cancer risk in women (Canada)

Objective: To investigate the association between dietary carotenoid intake and lung cancer risk in women. Methods: A case–cohort study was undertaken in the Canadian National Breast Screening Study dietary cohort, which consists of 56,837 women who completed a self-administered dietary questionnaire. The cohort was recruited between 1980 and 1985, and during follow-up to the end of 1993 a total of 196 cohort members were diagnosed with incident lung cancer. For analysis, a subcohort consisting of a random sample of 5681 women was selected from the full dietary cohort. After exclusions for various reasons, the analyses were based on 155 cases and 5361 non-cases. Results: When compared to those in the lowest quartile level of intake, the adjusted incidence rate ratios (95% confidence intervals) for those in the highest quartile levels of -carotene, -carotene, -cryptoxanthin, lycopene, and lutein intake were 0.90 (0.51–1.58), 1.40 (0.76–2.59), 0.66 (0.33–1.32), 1.04 (0.61–1.76), and 1.26 (0.70–2.24), respectively; none of the associated tests for trend was statistically significant. Conclusion: These results suggest that there is no association between dietary carotenoid intake and lung cancer risk, at least for the range of intakes observed here.     

Dietary Patterns and Risk of Invasive Ductal and Lobular Breast Carcinomas: A Systematic Review and Meta-analysis

The histopathologic subtypes of breast cancer, including invasive ductal carcinoma (IDC) and invasive lobular carcinoma (ILC), differ in terms of risk factors, progression, and response to treatment. The PubMed/Medline, Web of Science, and Scopus databases were searched up to February 2020 for published studies on the association between dietary patterns (Western diet [WD] or Mediterranean diet [WD]) and the risk of IDC/ILC of breast. Multivariable adjusted relative risk (RR) and 95% confidence intervals (CIs) comparing the highest and lowest categories of WD and MD patterns were combined by using the random-effects meta-analyses. After searching the databases, 10 eligible studies on the association of diet and IDC (7 articles) and ILC (3 articles) were included in the analysis. A statistically significant adverse association was observed between MD and IDC in case–control studies (RR = 0.47; 95% CI, 0.39-0.55; I² = 85.1%; P < .001). However, the association was nonsignificant in cohort studies (RR = 0.98; 95% CI, 0.92-1.05; I² = 88.8%; P = .003). The pooled analysis also suggested a significant and direct association between the WD and the risk of IDC (RR = 1.36; 95% CI, 1.18-1.53; I² = 63.7%; P = .017). The risk of ILC for the highest compared to the lowest category of MD was highly protective (RR = 0.76; 95% CI, 0.64-0.87; I² = 89.2%; P < .001), and a marginally significant association was found between the WD and risk of ILC (RR = 1.45; 95% CI, 1.04-1.86), with no heterogeneity (I² = 0; P = .52). This meta-analysis provides supporting evidence for the association between MD decreased risk of IDC and ILC of the breast and the association between WD and increased risk of IDC and ILC. Further investigations are needed to better understand the reasons behind the etiologic mechanisms of how dietary patterns affect patients differently by common breast cancer subtypes, including IDC and ILC.     

Growth of xenotransplanted leukemia cells is influenced by diet nutrients and is attenuated with 2-deoxyglucose

We examined the effects of diet nutrients on xenotransplanted leukemia cells, THP-1 or NB4. THP-1 tumors showed more growth when fed with high fat diet, while NB4 tumors grew more with high carbohydrate diet. Then, administration of 2-deoxyglucose (a glycolysis inhibitor) showed a significant antitumor effect on both tumors: NB4 tumor showed large necrotic areas, while THP-1 tumor did not, but had augmented expression of enzymes for fatty acid oxidation. 2-Deoxyglucose inhibited the growth of NB4 by cell death because main energy producing pathway (glycolysis) was abolished, while 2-deoxyglucose slowed the growth of THP-1 by shifting energy metabolism to fatty acid β-oxidation.     

生酮饮食在肿瘤治疗中的临床应用进展

随着现代科学技术的进步和日益提高的生物化学知识水平,营养学在日常生活以及医疗中的作用开始逐步显 现。利用营养学相关知识补充或者甚至用病理学条件下的饮食控制替代药物来治疗疾病已经得以实现。此外,使用营养作 为辅助治疗方法以协同的方式增强药物效应,降低可能产生的不良反应和依赖性在众多领域中也得到了广泛证实。伴随肿 瘤细胞代谢特点的研究深入,有实验表明,肿瘤细胞共有的最重要的特征是无论在有氧还是无氧条件下均主要使用葡萄糖 （Warburg 效应）进行供能。正是由于这种特殊的代谢方式,饮食控制被认为是肿瘤治疗中的重要策略。生酮饮食是一种 高脂肪、低蛋白质和极低碳水化合物饮食方法,这种饮食的治疗机制可能潜在地影响肿瘤治疗和预后。生酮饮食治疗作为 非药物治疗的重要组成部分 , 在国内外已系统广泛应用于小儿难治性癫痫治疗中 , 并取得显著成效。虽然生酮饮食在肿瘤动 物模型实验上取得不错的效果,但临床实验研究却鲜有报道。因此,本文从生酮饮食在肿瘤治疗中的作用机制、临床应用 效果方面综述了生酮饮食对于肿瘤患者的影响 , 为肿瘤非药物治疗研究提供借鉴。     

Enhancing Effects of Calcium-deficient Diet on Gastric Carcinogenesis by N-Methyl-N'-nitro-N-nitrosoguanidine in Wistar Rats

The effects of ad libitum feeding of calcium-deficient diet on the incidence, number and histological types of gastric cancers induced by N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) were investigated in male Wistar rats. Rats were fed standard pellet diet containing 0.5% (normal-calcium diet) or 0.01% calcium (calcium-deficient diet) after oral treatment with MNNG for 25 weeks. Oral administration of the calcium-deficient diet resulted in a significant increase in the incidence, hut not the number, of gastric cancers in experimental Week 52. However, it did not affect the histological types of cancer. The calcium-deficient diet also caused a significant increase in tissue norepinephrine concentration of the antral portion of the gastric wall and in the labeling index of the antral epithelial cells. These findings indicate that the calcium-deficient diet enhanced gastric carcinogenesis and suggest that its effect may be related to increase in norepinephrine in the gastric wall and consequent stimulation of proliferation of antral epithelial cells.     

饮食与肺癌关系的Meta分析

[目的]探讨饮食与肺癌发病的相互关系.[方法]利用Meta分析专用软件STATA对我国1990～2015年间55篇公开发表的有关饮食因素与肺癌的病例对照研究资料进行定量综合分析.[结果]酸食(OR=0.722,95％CI:0.564～0.923)、辣食(OR=0.537,95％CI:0.418～0.690)、蒜类食物(OR =0.773,95％ CI:0.668～0.894)、蔬菜(OR =0.578,95％ CI:0.495 ～0.675)、水果(OR=0.709,95％ CI:0.640～0.785)、豆类及其制品(OR =0.634,95％ CI:0.445 ～0.903)、蛋类(OR=0.527,95％ CI:0.378 ～0.736)、鱼类(OR =0.706,95％ CI:0.505 ～0.988)、维生素及胡萝卜素(OR=0.486,95％CI:0.366～0.646)和饮茶(OR=0.622,95％CI:0.542～0.713)是肺癌发病的保护因素.喜欢咸食(OR=2.114,95％CI:1.542～2.898)、甜食(OR=1.509,95％CI:1.186～1.920)、腌制食品(OR=1.504,95％CI:1.177～1.922)、煎炸、烟熏或烧烤食品(OR=1.754,95％CI:1.518 ～2.027)、动物内脏(OR=1.956,95％ CI:1.539 ～2.486)、食用动物油(OR=1.797,95％ CI:1.091～2.486)、少食蔬菜(OR=1.884,95％CI:1.469～2.417)、少食水果(OR=2.105,95％CI:1.421～3.119)、少食奶制品及其制品(OR=1.470,95％CI:1.025 ～2.107)、维生素及胡萝卜素摄入少(OR=1.647,95％CI:1.305 ～2.080)和饮酒(OR=1.382,95％CI:1.213 ～ 1.575)是肺癌发病的危险因素.食用植物油(OR=0.968,95％CI:0.434～2.158)、奶类及其制品(OR=0.648,95％CI:0.334～1.259)、肉类(OR=0.823,95％CI:0.641～1.055)、禽类(OR=0.763,95％ CI:0.433～1.347)、海产品(OR=0.686,95％ CI:0.417 ～ 1.130)、螺贝类(OR=0.609,95％CI:0.248～1.494)、经常服用补品(OR=1.005,95％CI:0.322～3.140)和高脂饮食(OR=1.397,95％CI:0.769～2.540)对肺癌发病的作用无统计学意义.[结论]饮食因素与肺癌发病密切相关,健康的饮食是肺癌发生的保护因素,不健康的饮食习惯可使肺癌的发病风险显著上升.