The Potential Role of Probiotics in Cancer Prevention and Treatment

The human gut microbiota has a significant effect on many aspects of human physiology such as metabolism, nutrient absorption, and immune function. Imbalance of the microbiota has been implicated in many disorders including inflammatory bowel disease, obesity, asthma, psychiatric illnesses, and cancers. As a kind of functional foods, probiotics have been shown to play a protective role against cancer development in animal models. Clinical application of probiotics indicated that some probiotic strains could diminish the incidence of postoperative inflammation in cancer patients. Chemotherapy or radiotherapy-related diarrhea was relieved in patients who were administered oral probiotics. The present review summarizes the up-to-date studies on probiotic effects and the underlying mechanisms related to cancer. At present, it is commonly accepted that most commercial probiotic products are generally safe and can improve the health of the host. By modulating intestinal microbiota and immune response, some strains of probiotics can be used as an adjuvant for cancer prevention or/and treatment.     

A Comparison of Breast Cancer Diagnosis and Treatment Between Lesbian and Heterosexual Women

Purpose/objectives: The purpose of this observational study was to explore differences and similarities in the diagnosis and treatment of lesbians and heterosexual women with breast cancer. Design: Nested survey. Sample and setting: The eligibility criteria for this study were: participation in a survey about the risks for developing breast cancer, diagnosed with breast cancer, returned a prepaid postcard with their name and address, and returned a completed survey about their breast cancer experiences. The typical participant (n = 80) was 55.4 years old (SD ± 9.1, range 41–78), educated with 17.3 years of schooling (SD ± 3.1, range 12–23+), White (91%), urban (44%), and employed (72.5%). Most had health insurance (95%), and currently 15% were on disability or taking sick leave from their jobs. Measurements: The 58-item survey was created, pilot-tested, and revised prior to being utilized in this study. Content validity was established by a multidisciplinary panel of experts. Many of the items had been successfully used in the principal investigator's previous studies. Results: There were no significant differences in demographics, diagnostic procedures, surgical procedures, chemotherapy regimens, or radiation therapy between the lesbians and the heterosexual women in this study. There were, however, significant differences in chemotherapy-induced side effects between the two groups. The lesbians reported significantly more problems than did the heterosexual women. Conclusions: Our study suggests that there are few differences in the diagnosis and treatment of breast cancer between lesbians and heterosexual women except in chemotherapy-induced side effects. However, this study will need to be replicated with a much larger sample size before any conclusions can be drawn about the diagnosis and treatment of lesbians diagnosed with breast cancer.     

Probiotics for the Prevention of Ventilator-Associated Pneumonia: An Updated Systematic Review and Meta-Analysis of Randomised Controlled Trials

Background: Presently, there is conflicting evidence regarding the efficacy of probiotics in the prevention of ventilator-associated pneumonia (VAP). This meta-analysis was conducted to update current clinical evidence and evaluate the efficacy and safety of probiotics for the prevention of VAP. Methods: We searched three databases and two trial registers to retrieve randomised controlled trials (RCTs) comparing probiotics or synbiotics with placebo or standard treatment for the prevention of VAP in adult patients receiving mechanical ventilation in the intensive care unit (ICU). Results: Our meta-analysis included 18 RCTs involving 4893 patients. Our results showed that probiotics may reduce the incidence of VAP (RR 0.68, 95% CI: 0.55–0.84; low certainty). However, in our subgroup and sensitivity analyses, the effect was not significant in double-blind studies, and in studies with a low risk of bias in the randomisation process. Probiotics reduced the length of ICU stay (MD −2.22 days, 95% CI: −4.17 to −0.28; moderate certainty) and the duration of antibiotic use (MD −1.25 days, 95% CI −1.86 to −0.64; moderate certainty). Conclusions: Probiotics may reduce the incidence of VAP but due to the low quality of pooled evidence, the use of probiotics warrants caution. Further, large-scale, high-quality RCTs need to be conducted to provide conclusive evidence.     

Dietary conjugated linoleic acid and long-chain n-3 fatty acids in mammary and prostate cancer protection: a review

The role of dietary fatty acids on cancer is still controversial. To examine the current literature on the protective role of conjugated linoleic acid (CLA) and marine long-chain fatty acids [eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)] and the risk of breast and prostate cancer, data from 41 case-control and cohort studies and relevant in vitro and animal experiments were included in this 2000–2010 revision. Epidemiological studies on CLA intake or its tissue concentration related to breast and prostate tumorigenesis are not conclusive; EPA and DHA intake have shown important inverse associations just in some studies. Additional research on the analysed association is required.     

Probiotic use in clinical practice: what are the risks?

Probiotics have been advocated for the prevention and treatment of a wide range of diseases, and there is strong evidence for their efficacy in some clinical scenarios. Probiotics are now widely used in many countries by consumers and in clinical practice. Given the increasingly widespread use of probiotics, a thorough understanding of their risks and benefits is imperative. In this article we review the safety of probiotics and discuss areas of uncertainty regarding their use. Although probiotics have an excellent overall safety record, they should be used with caution in certain patient groups-particularly neonates born prematurely or with immune deficiency. Because of the paucity of information regarding the mechanisms through which probiotics act, appropriate administrative regimens, and probiotic interactions, further investigation is needed in these areas. Finally, note that the properties of different probiotic species vary and can be strain-specific. Therefore, the effects of one probiotic strain should not be generalized to others without confirmation in separate studies. Careful consideration should be given to these issues before patients are advised to use probiotic supplements in clinical practice.     

Dietary lignans: potential role in cancer prevention

Recent in vitro, animal, and epidemiological studies suggest that dietary lignans may be chemopreventive, potentially through anti-estrogenic, anti-angiogenic, pro- apoptotic, and anti-oxidant mechanisms. In this article, we review lignan food sources and metabolism, proposed anti-carcinogenic mechanisms, and the evidence for a role of lignans in breast, colon, and prostate cancer prevention from animal and epidemiologic literature. Although a number of in vitro and animal studies support a role for lignan-rich foods and purified lignans in the modulation of cancer events of the breast, prostate, and colon, epidemiological studies, sparse and often retrospective in nature, offer inconsistent findings. The most support for a role of lignans in cancer is observed for premenopausal breast cancer. Additional epidemiological studies that use a prospective design and well-developed food databases and questionnaires are needed to adequately evaluate the role of lignans in cancer prevention.     

Vitamin E and its Role in the Prevention of Atherosclerosis and Carcinogenesis: A Review

Epidemiological and experimental studies suggest that antioxidants like vitamin E (α-tocopherol) may play an important role in prevention of chronic disease. Several observational surveys have linked populations with a large intake of vitamin E with reduced incidence of heart disease. These observations have been strengthened by the demonstration of strong antioxidant activity by vitamin E in cellular, molecular and animal experiments. These results have highlighted a potential role for vitamin E supplementation in the prevention of chronic disease in humans. Interestingly however, large-scale clinical trials of vitamin E and other antioxidants in preventing specific disease processes (e.g., coronary artery disease) have generated conflicting and mixed outcomes. In this review, the role of vitamin E in the prevention of atherosclerosis and carcinogenesis has been carefully examined with particular emphasis on salient human studies (clinical trials) and their limitations. In addition, pertinent biochemical, physiological and metabolic features of vitamin E have also been incorporated. A list of common natural food sources of vitamin E has been provided. Important in vitro and animal studies related to the antiatherosclerotic and anticarcinogenic actions of vitamin E have been discussed in detail. Finally, the direction of future investigations in primary and secondary prevention of chronic diseases by vitamin E supplementation has been outlined.     

Review of the mechanisms of probiotic actions in the prevention of colorectal cancer

The purpose of this review is to discuss the potential mechanisms of probiotics action in colorectal cancer prevention. In this regard, the composition of the intestinal microbiota is considered as an important risk factor in the development of colorectal cancer, and probiotics are able to positively modulate the composition of this microbiota. Studies have shown that the regular consumption of probiotics could prevent the development of colorectal cancer. In this respect, in vitro and experimental studies suggest some potential mechanisms responsible for this anticarcinogenic action. The mechanisms include modification of the intestinal microbiota composition, changes in metabolic activity of the microbiota, binding and degradation of carcinogenic compounds present in the intestinal lumen, production of compounds with anticarcinogenic activity, immunomodulation, improvement of the intestinal barrier, changes in host physiology, inhibition of cell proliferation, and induction of apoptosis in cancer cells. In contrast, very few reports demonstrate adverse effects of probiotic oral supplementation. In light of the present evidence, more specific studies are needed on probiotic bacteria, especially regarding the identification of the bacterial strains with greater anticarcinogenic potential; the verification of the viability of these strains after passing through the gastrointestinal tract; the investigation of potential adverse effects in immunocompromised individuals; and finally establishing the dosage and frequency of use.     

Probiotics: From Isolation to Application

Probiotics have become highly recognized as supplements for humans and animals because of their beneficial effects on health and well-being. The present review aims to provide an overview of different steps through which microbial strains become applicable probiotics in food and/or feed industries. Isolation of potential probiotic strains is the first step. Lactic acid bacteria are the most frequently used microorganisms as probiotics, which can be isolated from human, animal, plant, and environment. The next steps are identification of the isolates and characterization of them based on the main selection criteria for any potential probiotic microorganism, including resistance to gastric acidity and bile salt, adherence to mucus and/or intestinal epithelial cells and cell lines, and antimicrobial and antagonism activity against potentially pathogenic microbes. There are additional probiotic properties that may be considered for selection of probiotic strains with specific effects, such as cholesterol reduction ability, antioxidant activity, or cytotoxic effect against cancer cells. However, a potential probiotic does not need to fulfill all such selection criteria. As the last step, safety status of probiotics for humans is verified by taxonomy clarification, in vitro and in vivo tests, human trials, and genome sequencing.     

Role of probiotics in modulating glucose homeostasis: evidence from animal and human studies

Abstract

Aim: Evidences from several studies suggest that probiotics affect glucose homeostasis. This paper reviews the results of animal and human studies on the role of probiotics in modulating glucose homeostasis. Method: A systematic literature search using multiple databases was conducted without time limitation. Primary outcomes evaluated were parameters related to glucose homeostasis. Secondary outcomes were inflammatory markers, lipid profile, body weight, and energy intake. Results: A total of 17 animal studies and four human studies were identified. Among these, 16 animal studies and three human studies had documented significant improvements in at least one glucose homeostasis related parameter. Inflammatory markers and lipid profile were significantly improved in the animal model, while data from human studies were controversial. Changes in body weight and energy intake that could be due to probiotics supplementation were also inconclusive. Conclusion: Well-designed placebo-controlled clinical trials with validated outcome variables are needed to determine the effect of probiotics on glucose homeostasis.     

Development and evaluation of a decision aid for patients considering first-line chemotherapy for metastatic breast cancer

Objective Treatment decisions in advanced breast cancer are complex, with enhanced quality of life and survival among important treatment goals. Patients with metastatic breast cancer face the decision of whether or not to have chemotherapy, and many wish to be involved in this decision. We report the development and evaluation of a decision aid (DA) designed to assist patients facing this treatment decision. Design and sample Women with metastatic breast cancer (n = 17) and medical oncologists in Australia and Canada (n = 7) were invited to evaluate the DA. Intervention A DA was developed for patients with hormone‐resistant metastatic breast cancer considering chemotherapy. The DA presented options of supportive care, with or without chemotherapy. Potential benefits and side effects of different chemotherapy regimens, and evidence‐based prognostic estimates were described, and a values clarification exercise included. Main outcome measures Patient questionnaires evaluating information and decision involvement preferences, attitudes toward the DA and oncologist feedback regarding attitudes toward the DA. Results Seventeen patients participated; fifteen desired as much information about their illness as possible; sixteen wished to be actively involved in the decision‐making process. The majority rated the DA as highly acceptable, clear and informative, and would recommend it to others facing this treatment decision. Conclusion This is the first DA for patients with advanced metastatic breast cancer considering chemotherapy. A randomized trial is underway to evaluate its role in clinical decision‐making.     

Use of Probiotics in the Management of Chemotherapy‐Induced Diarrhea: A Case Study

Gastrointestinal disturbances (particularly diarrhea) are often induced in response to cancer treatments such as chemotherapy or radiation. Oral chemotherapeutic agents can induce diarrhea by damaging the intestinal lining. Two common oral drugs used in cancer treatment that are known to have gastrointestinal side effects are capecitabine and lapatinib. In this brief communication, the authors discuss a case study of a stage IV breast cancer patient whose chemotherapy‐induced diarrhea was treated successfully with a multispecies combination of probiotics. This is a unique study in which grade 3 chemotherapy‐induced diarrhea (characterized by 7–9 stools per day and associ ated with incontinence and abdominal cramping) was treated with only a multispecies combination of probiotics. Probiotics have been used to treat diarrhea in patients with irritable bowel syndrome, ulcerative colitis, pouchitis, and Crohn's disease. More recently, probiotics have been used to treat chemotherapy‐induced diarrhea in colon cancer patients. This case study demonstrates that the probiotics can also be used to treat severe cases of chemotherapy‐induced diarrhea in breast cancer patients. The use of different probiotics in gastrointestinal diseases is an increasingly important area of study, and more research into this area is needed. This study demonstrates that probiotics should be considered for advanced breast cancer patients with chemotherapy‐induced diarrhea.     

Mechanistic Insight of Probiotics Derived Anticancer Pharmaceuticals: A Road Forward for Cancer Therapeutics

Probiotics are living organisms that confer health benefits when administered in adequate amounts. Probiotics are continuously being explored for their different health beneficiary activities. Anticancer activity is one of the most important benefits both from a preventive and therapeutic point of view. Though not many studies have been conducted to date in this area, a number suggest using laboratory animal models and different cell lines that there may be a mechanistic basis for the anticancer effects of probiotics and require more scientific justification and clinical trials. Most studies of probiotics are conducted for colon cancer associated with inflammatory bowel disease. Studies are also being extended to other types of cancer in different cell lines. This review summarizes studied probiotics considered for treatment of colon cancer and some other cancers (in cancer cell lines) and also proposed mechanism how probiotics are inhibiting cancer growth along with some challenges and future perspectives.     

江门市2003—2007年乳腺癌发病状况分析

目的分析广东省江门市2003—2007年乳腺癌的发病：死亡及危险因素，探索其流行规律。方法对乳腺癌的发病率、发病年龄及疗效等指标进行回顾性分析。结果乳腺癌发病居五年女性恶性肿瘤第一位，且有逐渐上升趋势，40--岁，50--岁两个年龄组为乳腺癌发病高峰年龄段。职业为工人的乳腺癌发病率为64．95％。近五年乳腺癌治愈和好转率达到94.8％。结论加强江门市乳腺癌防治工作。     

The effect of physical activity on breast cancer risk: A cohort study of 30,548 women

Background: In epidemiological studies abundant physical activity has been related to decreased breast cancer risk, though the results have been inconsistent. The purpose of this paper was to study the association of physical activity at leisure and commuting to work and incidence of breast cancer. Methods: The study cohort consisted of 30,548 female participants of the Finnish adult health behaviour survey, based on annual random samples of Finns aged 15–64, collected in 1978–1993. By the end of 1995, 332 breast cancer cases had been diagnosed in the cohort. Relative risks of breast cancer were adjusted for age at survey, body mass index (BMI), education, length of follow-up, parity and age at first birth using Poisson regression models. Results: Compared to women exercising less than once a week, the adjusted relative risk of breast cancer for women exercising once a week was 0.80 (95% confidence interval (CI): 0.58–1.10), for women exercising 2–3 times per week 0.92 (95% CI: 0.78–1.22) and for women exercising daily 1.01 (95% CI: 0.72–1.42). Women who reported commuting, walking or bicycling to work 30 min or more daily had slightly lower adjusted risk of breast cancer (RR: 0.87, 95% CI: 0.62–1.24) than women working at home, being unemployed or driving a car to working place. Conclusion: Although a small protective effect of regular physical activity for breast cancer incidence was found in physical activity when commuting to work, the role of the physical activity in breast cancer prevention is still an open question.     

Overall Dietary Intake and Prognosis after Breast Cancer: A Systematic Review

Breast cancer survivors often seek information about how lifestyle factors, such as diet, may influence their prognosis. Previous studies have reviewed evidence around single nutrients, individual foods or food groups. We reviewed studies examining relationships between overall dietary intake and prognosis in breast cancer survivors. A systematic search was conducted to identify studies, published until June 2016, which assessed associations between overall dietary intake (i.e., quality; score; pattern) and mortality and/or recurrence in breast cancer survivors. We identified seven eligible studies. Studies were heterogeneous regarding diet assessment timing (before/after diagnosis); mean age and menopausal status; and dietary intake measure (statistically derived/a priori defined indices). Better overall dietary intake (i.e., better quality; healthy/prudent pattern; less inflammatory diet) was associated with decreased risk of overall and non-breast cancer mortality, in most studies. Insufficient evidence is available to draw conclusions regarding breast cancer-specific survival and disease recurrence. Following breast cancer diagnosis, better overall dietary intake may independently improve overall and non-breast cancer survival. Survivors may improve prognosis by adopting more healthful dietary patterns consistent with dietary guidelines and/or prudent diet. Future adequately powered studies should consider measuring dietary intake consistently to better understand the role of diet in disease-specific outcomes.     

国产与进口流行性腮腺炎联合疫苗(MMR)免疫原性与安全性系统评价

目的比较国产与进口含流行性腮腺炎成分的联合疫苗(MMR)接种后的抗体阳转率和副反应发生率,评价二者免疫学效果和安全性的差异,为应对流行性腮腺炎高发病率的情况,甄选安全性强、高效能和经济适用的流行性腮腺炎疫苗提供依据。方法全面收集国内外已发表的研究数据,对国产麻疹风疹腮腺炎联合疫苗(MMR)与进口联合疫苗(MMR)在免疫原性和安全性上进行系统差异性比较。结果经纳入和排除标准筛选,最终提取6篇关于含流行性腮腺炎疫苗成分的国产联合疫苗(MMR)与进口联合疫苗(MMR)免疫原性的文献资料,以接种后腮腺炎抗体阳性率为分析指标,结果显示:国产MMR接种组和进口MMR接种组的抗体阳性率差异无统计学意义[RR=0.99,95%CI(0.96,1.03),P=0.671];入选的5篇文献报告了含腮腺炎疫苗成分的国产MMR组和进口MMR组接种后副反应发生率,研究发现:国产MMR接种组和进口MMR接种组在副反应发生率上差异无统计学意义[RR=1.05,95%CI(0.87,1.27),P=0.620]。结论在选择联合疫苗预防腮腺炎疾病时,国产MMR和进口MMR具有相同的优势,国产MMR在免疫原性和免疫安全性方面和进口疫苗无明显差异。     

Insulin-like growth factor-I and the gastrointestinal system: therapeutic indications and safety implications

Following the identification of insulin-like growth factor-I (IGF-I) as a potent trophic factor for the intestine over a decade ago, therapeutic indications have been identified for a range of candidate bowel disorders and diseases in which accelerated intestinal repair is desirable. Subsequent experimental studies in experimentally-induced animal models and genetically-modified mice have supported a therapeutic role for IGF-I in facilitated repair processes in gastrointestinal disorders including radiation enteritis, chemotherapy-induced mucositis and inflammatory bowel disease, conditions associated with either the pre-existence of malignancy or a predisposition to develop neoplasia. Moreover, recent evidence from in vitro, in vivo and human population studies is suggestive of an active role for IGF-I in the development and progression of certain cancers, and although causality remains unproven, antagonism of IGF-I action is being pursued as a potential chemo-preventive strategy. Novel milk and colostrum-derived bioactive formulations containing IGF-I are being developed as adjunctive treatment modalities for certain bowel disorders. Understanding the precise role of the IGF axis in cancer will either identify antagonism of the IGF-I/receptor interaction as an important approach in cancer prevention and risk reduction, or alternatively, support further development of IGF-I as a promising treatment modality for acute gastrointestinal disease.     

Folate and cancer prevention: a new medical application of folate beyond hyperhomocysteinemia and neural tube defects

Folate is an important cofactor in the transfer of one-carbon moieties and plays a key role in DNA synthesis, repair, and methylation. The role of folate has greatly evolved from the prevention of macrocytic anemia to the prevention of cardiovascular disease and neural tube defects. More recently, epidemiologic, animal, and clinical evidence suggests that folate may also play a role in cancer prevention. Two recently published large, prospective epidemiologic studies suggest that maintaining adequate levels of serum folate or moderately increasing folate intakes from dietary sources and vitamin supplements can significantly reduce the risk of pancreatic and breast cancer, respectively. This protective effect of folate appears to be operative in subjects at risk for developing these cancers, namely, male smokers for pancreatic cancer and women regularly consuming a moderate amount of alcohol for breast cancer. Because the expanding role of folate nutrition in cancer prevention has major public health implications, research is required to clearly elucidate the effect of folate on carcinogenesis.     

Oral Information About Side Effects of Endocrine Therapy for Early Breast Cancer Patients at Initial Consultation and First Follow-Up Visit: An Online Survey

This study was initiated to identify how physicians inform women about specific side effects of endocrine therapy for early breast cancer. It is recommended that women with early breast cancer receive endocrine treatment for at least 5 years. Although this medication is an important step in curing breast cancer, continued application by patients is far below 100%; 30–50% of all women prematurely end their prescribed therapy. In an online survey, physicians specializing in treating breast cancer (members of the Austrian Breast and Colorectal Cancer Study Group, ABCSG) were asked about their practice of informing patients about potential side effects of endocrine therapy for breast cancer. Two hundred and five members of the ABCSG completed the online questionnaire. The physicians indicated that patients were primarily informed regarding joint pain/muscle pain and flushes/sleep disturbances during the initial consultation as well as during the first follow-up visit. Patients were informed considerably less regarding side effects that influence quality-of-life areas, such as pain during intercourse, reduced orgasm capability, and hair loss. During the initial consultation, and during first follow-up visit, patients are not uniformly and are insufficiently informed about substantial side effects of endocrine therapy.