PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Cancer prevention”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 37 records · Page 2Linked to original sources
PubMed1986

Preventive cancer care for the elderly.

There is a great need for effective cancer prevention programs for the elderly. Unfortunately, the elderly have been omitted from most studies of cancer prevention; little is currently known concerning the benefits, risks, and feasibility of most primary and secondary cancer prevention measures in this segment of the population. Available data justify annual casefinding activities in the office of the primary care physician for breast cancer in elderly women and colorectal cancer in elderly persons of both sexes. PAP smear screening is also indicated for elderly women who have had few or no PAP smear in the past. There is some evidence that the health beliefs and practices of elderly persons and their physicians may impede the utilization of available cancer prevention measures. Further research is needed to define the efficacy of cancer prevention measures for the elderly and to improve the delivery of these measures to the elderly population.

Aged↗
PubMed1994

[Antioxidant minerals and vitamins. Role in cancer prevention].

Cancer is a disease of the genome and free-radicals can damage genomic DNA, hence the interest in the potential protective antioxidant effect of vitamin and minerals. Indeed, the findings of most retrospective studies suggest that diets rich in fruits and vegetables have a protective effect against cancer. Prospective randomized trials have however given controversial results. Beta-carotene, the precursor of vitamin A has been shown to induce regression of precancerous lesions and 13-cis retinoic acid has a preventive effect on the development of a second cancer in patients with epidermoid cancer of the buccal cavity, the pharynx or the larynx although no effect has been observed on the primary cancer. Current research also suggests vitamin C has a potential anticancer effect, particularly for cancer of the stomach, the rectum and the cervix. For vitamin E, epidemiological data give less conclusive results. Several prospective studies suggest the absence of any correlation between vitamin E intake and general risk of cancer. A Chinese trial has shown a decreased incidence of oesophageal and gastric carcinoma while a Finnish trial revealed increased incidence of cancer among smokers treated by beta-carotene and vitamin E. Selenium and zinc intake, based on geographical correlations, has also been suggested to affect cancer incidence, but the results of prospective studies are conflicting. For example in 10 such trials analyzing blood selenium levels and risk of cancer, 4 have demonstrated a significant correlation. Further research is needed but is hindered by the absence of an adequate animal model and the difficulty in conducting large clinical trials. Nevertheless, positive data collected to date must be validated to determine the real effect of dietary preventive measures in the fight against cancer.

Animals↗
PubMed1995

Cancer prevention strategies: use of cancer prevention research registries.

We present a model to plan a rational strategy for cancer prevention that has two main functions--assessment and intervention. The assessment function includes three main components: to identify populations at high cancer risk, which may be due to their ethnic group, occupational and environmental exposures, family history, cigarette smoking, or other risk factors; to assess exposure to known carcinogens through the general and occupational environments, lifestyle factors, and the home as well as to document known carcinogens using human tissue banks and develop and validate questionnaires to target known risk factors for each of the most common cancers; and to conduct research studies of high-risk populations, including studies on mechanism and genetic testing. The intervention function includes three components: development of population-based intervention programs using the results from the research studies; evaluation of intervention programs; and modification of existing intervention programs and implementation of new ones. The above-proposed prevention strategy depends to a great extent on population-based cancer registries. Existing cancer registries around the United States should be strengthened and other dimensions should be added to their charge to augment their function in prevention research. To convert existing population-based cancer registries, particularly those that serve multiethnic and multicultural populations, into Cancer Prevention Research Registries (CPRRs), three types of data in addition to their existing required data complement should be incorporated. These are exposure information including occupational history, host factors information, and information about family history of cancer and associated conditions. The primary goal of the CPRRs should be to support cancer prevention research in its widest sense. Future research needs must be designed to investigate each of the components of the prevention strategy as well as its integrated performance. Regardless of what we do in the future, we must now promote healthier lifestyles, prevent exposure to known carcinogens, and improve early detection procedures.

Carcinogens, Environmental↗
PubMed2002

Discovery of cancer preventive agents from natural products: from plants to prevention.

Cancer chemoprevention has traditionally been defined as a dietary or therapeutic approach for the prevention, delay, or reversal of carcinogenesis. We currently expand this definition to include nontoxic applications for patients with established disease. In this context, efficacy can be achieved by selectively altering cell-cycle progression. In the quest for new cancer chemopreventive agents, we have focused on the isolation of natural products as lead molecules, followed by synthetic modification to improve activity. Using biologic response as a guide for fractionation, over 200 active compounds have been identified. Some of the most interesting include brassinin and 4'-bromoflavone as inducers of quinone reductase, deguelin as an inhibitor of ornithine decarboxylase, resveratrol as an inhibitor of cyclooxygenase, and brusatol as an inducer of cellular differentiation. These agents have demonstrated effectiveness in experimental models of carcinogenesis. Further development of these agents as chemopreventive drugs may proceed through the normal regulatory process (eg, 4'-bromoflavone). Alternatively, some natural products may be administered as dietary supplements (eg, resveratrol). In either case, chemoprevention offers great hope in reducing the morbidity and mortality associated with cancer.

Anticarcinogenic Agents↗
PubMed1988

Screening: potential for cancer prevention.

Cancer screening is the application of a test in large numbers of asymptomatic persons for the early detection of cancer. The objective is to reduce deaths among the population screened. Prerequisites for implementation of cancer screening are sufficient knowledge of the biology of the cancer, an appropriate screening test, an effective intervention, either by removal or with curative treatment, and the decision that the costs are worth the benefits. At this time, screening asymptomatic women for early detection of cancers of the cervix using the Pap test and breast using mammography has the greatest potential for the control of these common cancers.

Breast Neoplasms↗
PubMedDate not supplied

Epidemiology: a step forward in the scientific approach to preventing cancer through chemoprevention.

Until quite recently, the rigor and systematic approach applied to clinical research had never been applied to cancer prevention research. During 1982-83, however, the National Cancer Institute (NCI) carefully reviewed the needs and potentials in cancer prevention and control and developed a new policy for prevention research, requiring that development of cancer intervention follow an orderly sequence of research phases. These phases provide systematic assessment of interventions so that only those proven to be effective are brought to widespread implementation. The author presents an overview of the new cancer prevention research policy; explains the manner in which epidemiologic studies contribute to development of policy and research; and describes NCI's research plan for chemoprevention, providing highlights of research studies that have contributed to its development and that will be implemented under the plan.

Diet↗
PubMed1996

[Chemoprevention of cancer. Prevention of cancer in groups with increased risk].

The term chemoprevention is defined as the use of specific natural or synthetic chemical agents to reverse, suppress or prevent carcinogenic development to a tumour. Many potential chemopreventive substances are pharmacologic agents which may already be in use or are naturally occurring compounds. Short-term tests and animal models are available for identifying potential chemopreventive agents. There are several similarities between clinical chemopreventive trials and cancer prevention by dietary intervention. The cost and length of chemopreventive trials can be reduced by using validated biomarkers as endpoint instead of cancer. Experience from chemoprevention of cancer is limited, seen in relation to use of chemical agents to reduce cardiovascular disease. However, a number of international clinical trials are now going on to evaluate the use of pharmacological substances as potential chemopreventive agents.

Anticarcinogenic Agents↗
PubMedDate not supplied

Guidelines on diet, nutrition, and cancer prevention: reducing the risk of cancer with healthy food choices and physical activity. The American Cancer Society 1996 Advisory Committee on Diet, Nutrition, and Cancer Prevention.

The American Cancer Society periodically assembles an expert advisory committee to evaluate recent evidence and update the American Cancer Society's guidelines for diet, nutrition, and cancer prevention. This year's update presents four broad guidelines to reduce cancer risk and provides information on a wide variety of topics concerning nutrition and cancer.

Diet↗
PubMed2003

Mechanisms of cancer prevention by tea constituents.

Consumption of tea (Camellia sinensis) has been suggested to prevent cancer, heart disease and other diseases. Animal studies have shown that tea and tea constituents inhibit carcinogenesis of the skin, lung, oral cavity, esophagus, stomach, liver, prostate and other organs. In some studies, the inhibition correlated with an increase in tumor cell apoptosis and a decrease in cell proliferation. Studies with human cancer cell lines have demonstrated that epigallocatechin-3-gallate (EGCG), a major tea polyphenol, inhibits mitogen-activated protein kinases, cyclin-dependent kinases, growth factor-related cell signaling, activation of activator protein 1 (AP-1) and nuclear factor kappaB (NFkappaB), topoisomerase I and matrix metalloproteinases as well as other potential targets. Although some studies report effects of EGCG at submicromolar levels, most experiments require concentrations of >10 or 20 micromol/L to demonstrate the effect. In humans, tea polyphenols undergo glucuronidation, sulfation, methylation, and ring fission. The peak plasma concentration of EGCG is approximately 1 micromol/L. The possible relevance of each of the proposed mechanisms to human cancer prevention is discussed in light of current bioavailability data for tea polyphenols and the potential limitations of animal models of carcinogenesis. Such discussion, it is hoped, will clarify some misunderstandings of cancer prevention by tea and stimulate new research efforts.

Animals↗
PubMed2006

Perceived ambiguity about cancer prevention recommendations: relationship to perceptions of cancer preventability, risk, and worry.

In this study, we apply the concept of "ambiguity," as developed in the decision theory literature, to an analysis of potential psychological consequences of uncertainty about cancer prevention recommendations. We used Health Information National Trends Survey (HINTS) 2003 data to examine how perceived ambiguity about cancer prevention recommendations relates to three other cognitive variables known to influence cancer-protective behavior: perceived cancer preventability, perceived cancer risk, and cancer-related worry. Using logistic regression analyses, we tested several predictions derived from a review of literature on the effects of ambiguity perceptions on decision making, cognitions, and emotions. We found perceived ambiguity to have a strong negative relationship with perceived cancer preventability, consistent with "ambiguity aversion"-a pessimistic bias in the interpretation of ambiguity. Cancer worry moderated this relationship; ambiguity aversion increased with higher levels of worry. At the same time, perceived ambiguity was positively related to both perceived cancer risk and cancer worry. Furthermore, perceived risk partially mediated the relationship between perceived ambiguity and worry. These findings suggest that perceived ambiguity about cancer prevention recommendations may have broad and important effects on other health cognitions. We discuss ethical implications of these findings for health communication efforts, and propose a tentative causal model to guide future research.

Adult↗
PubMed1993

Scientific basis for cancer prevention. Intermediate cancer markers.

Promising cancer clinical trials results involving the disruption of early stages of cancer with intervention agents such as tamoxifen or retinoids have led to significant new research interest in developing preventative strategy for the control of epithelial cancers. Key to the efficient progress in this field is a clear understanding of the complex biology of the early stages of cancerization that proceed on the epithelial surface. Systematic analysis of the biology of strategic targets such as growth factors is one approach to this problem. Gastrin-releasing peptide is an autocrine growth factor for certain types of lung cancer cells. Mechanisms involved in the production and activation of this peptide are discussed as an example of how rational approaches to neutralization of cancer promotion biology can be achieved. The tools to monitor the success of this type of intervention also emerge from the understanding of the biology of growth factors, and intermediate end point markers that determine the presence or effects of a growth factor are attractive candidates for evaluation. Additional biologic tools reflecting the early stages of the cancer process need to be validated for use in serially evaluating the status of the relevant epithelium so that the ongoing success of a cancer intervention procedure can be established. Through this type of translational research, important applications of molecular biology may greatly improve the success of preventative strategies for cancer control.

Anticarcinogenic Agents↗
PubMed2001

SELECT: the next prostate cancer prevention trial. Selenum and Vitamin E Cancer Prevention Trial.

PURPOSE: Growing evidence implies that selenium and vitamin E may decrease the risk of prostate cancer. The Selenium and Vitamin E Cancer Prevention Trial (SELECT) is a randomized prospective double-blind study designed to determine whether selenium and vitamin E decrease the risk of prostate cancer in healthy men. MATERIALS AND METHODS: The preclinical and epidemiological evidence regarding chemoprevention with selenium and vitamin E were reviewed. Secondary analyses from randomized trials of the 2 agents were included in the current analysis. Data from these analyses as well as evidence from the Prostate Cancer Prevention Trial were used to develop the SELECT schema. RESULTS: Preclinical, epidemiological and phase III data imply that selenium and vitamin E have potential efficacy for prostate cancer prevention. The experience of the Prostate Cancer Prevention Trial shows the interest and dedication of healthy men to long-term studies of cancer prevention. A total of 32,400 men are planned to be randomized in SELECT. CONCLUSIONS: SELECT is the second large-scale study of chemoprevention for prostate cancer. Enrollment in the study is planned to begin in 2001 with final results anticipated in 2013.

Double-Blind Method↗
PubMed2000

Harvard report on cancer prevention volume 4: Harvard Cancer Risk Index. Risk Index Working Group, Harvard Center for Cancer Prevention.

OBJECTIVE: Prediction of cancer risk is a minor component of current health risk appraisals. Perception of individual cancer risk is poor. A Cancer Risk Index was developed to predict individual cancer risk for cancers accounting for 80% of the cancer burden in the United States. METHODS: We used group consensus among researchers at the Harvard Medical School and Harvard School of Public Health to identify risk factors as definite, probable and possible causes of cancer. Risk points were allocated according to the strength of the causal association and summed. Population average risk of cancer and cumulative 10-year risk was obtained from SEER data. Individual ranking relative to the population average was determined. The risk index was evaluated for validity using colon cancer incidence in prospective cohort data. RESULTS: The Harvard Cancer Risk Index provides a broad classification of cancer risk. Validation against cohort data shows good agreement for colon cancer. CONCLUSION: The Harvard Cancer Risk Index offers a simple estimation of personal risk of cancer. It may help inform users of the major risk factors for cancer and identify changes in lifestyle that will reduce their risk. It offers the potential for tailored health-promotion messages.

Adult↗
PubMed2004

Is vaccine therapy the future in cancer prevention?

One vaccine designed to prevent cancer by preventing a precursor infection is already in common use, and at least one more is in the latter stages of clinical development. These vaccines are part of a new era of cancer immunoprophylaxis. Several further vaccines are in preclinical and clinical development, targeted at preventing cancer precursor infections, and these should add to our ability to prevent this common human disorder. However, vaccines to prevent cancers not triggered by infection are a more remote prospect, for a variety of reasons.

Antigens, Neoplasm↗
PubMed2000

[From cancer prevention to cancer treatment].

Cancer is a common life-threatening disease. Prevention and therapy of the disease are the desire of everybody. This paper summarizes our attempt to the tough challenge. Chronologically we began the study of carcinogenesis, and then turned to the research of anticancer agents. Identification of food mutagens was extensively studied. Once they were identified, the mechanism of nucleic acid modifications by these mutagens had been studied. The modification study gave information on the nucleic acid modification by mitomycin and bleomycin. The structure-activity relationship study of phorbol esters and teleocidines whose tumor promotion is epigenetic, was extensively studied. On the other hand, retinoic acid, a vitamin A metabolite, suppresses the epigenetic tumor promotion. This suggests that an epigenetically active compound rather than a cytotoxic anticancer agent can be used for tumor suppression. In the retinoid research, we found a number of characteristic new active substances which may be of therapeutic use: some of them are in the clinical trial stages in the field of dermatology and cancer. During the chemical study of retinoids, we encountered the retinoic acid receptor, coded by the retinoic acid receptor (RAR) gene which had just reported. Further retinoid research yielded retinoids antagonists, and then RXR(retinoic acid-X-receptor)-agonists and RXR-antagonists. These ligands have a big potential in the therapy of diabetes and obesity.

Animals↗
PubMed2001

Allium vegetables and organosulfur compounds: do they help prevent cancer?

Allium vegetables have been shown to have beneficial effects against several diseases, including cancer. Garlic, onions, leeks, and chives have been reported to protect against stomach and colorectal cancers, although evidence for a protective effect against cancer at other sites, including the breast, is still insufficient. The protective effect appears to be related to the presence of organosulfur compounds and mainly allyl derivatives, which inhibit carcinogenesis in the forestomach, esophagus, colon, mammary gland, and lung of experimental animals. The exact mechanisms of the cancer-preventive effects are not clear, although several hypotheses have been proposed. Organosulfur compounds modulate the activity of several metabolizing enzymes that activate (cytochrome P450s) or detoxify (glutathione S-transferases) carcinogens and inhibit the formation of DNA adducts in several target tissues. Antiproliferative activity has been described in several tumor cell lines, which is possibly mediated by induction of apoptosis and alterations of the cell cycle. Allium vegetables and organosulfur compounds are thus possible cancer-preventive agents. Clinical trials will be required to define the effective dose that has no toxicity in humans.

Allium↗