Nutritional Oncology

George L. Blackburn, Vay Liang W. Go, John Milner

• Publisher: Academic Press
• Year: 2011
• eBook ISBN: 9780080454177
• Edition: 2
• Topic: Medicine
• Subtopic: Oncology

Nutritional oncology is an increasingly active interdisciplinary field where cancer is investigated as both a systemic and local disease originating with the changes in the genome and progressing through a multi-step process which may be influenced at many points in its natural history by nutritional factors that could impact the prevention of cancer, the quality of life of cancer patients, and the risk of cancer recurrence in the rapidly increasing population of cancer survivors.Since the first edition of this book was published in 1999, the idea that there is a single gene pathway or single drug will provide a cure for cancer has given way to the general view that dietary/environmental factors impact the progression of genetic and cellular changes in common forms of cancer. This broad concept can now be investigated within a basic and clinical research context for specific types of cancer. This book attempts to cover the current available knowledge in this new field of nutritional oncology written by invited experts. This book attempts to provide not only the theoretical and research basis for nutritional oncology, but will offer the medical oncologist and other members of multidisciplinary groups treating cancer patients practical information on nutrition assessment and nutritional regimens, including micronutrient and phytochemical supplementation. The editors hope that this volume will stimulate increased research, education and patient application of the principles of nutritional oncology.NEW TO THIS EDITION:* Covers hot new topics of nutrigenomics and nutrigenetics in cancer cell growth * Includes new chapters on metabolic networks in cancer cell growth, nutrigenetics and nutrigenomics* Presents substantially revised chapters on breast cancer and nutrition, prostate cancer and nutrition, and colon cancer and nutrition* Includes new illustrations throughout the text, especially in the breast cancer chapter* Includes integrated insights into the unanswered questions and clearly defined objectives of research in nutritional oncology * Offers practical guidelines for clinicians advising malnourished cancer patients and cancer survivors on diet, nutrition, and lifestyle * Provides information on the role of bioactive substances, dietary supplements, phytochemicals and botanicals in cancer prevention and treatment

IV

Gene-Nutrient Interaction and Cancer Prevention

CHAPTER 18 The Challenge of Nutrition in Cancer Prevention

PETER. GREENWALD, JOHN. MILNER

OVERVIEW OF THE NUTRITION–CANCER RELATIONSHIP

Compelling evidence continues to accumulate to strengthen the link between diet and cancer. Information comes from a wide range of research initiatives, including population-based studies, ecological studies, human metabolic studies, methodology development, investigations of the basic mechanisms of action of dietary constituents, and clinical trials of dietary modification and the chemopreventive potential of individual nutrients or dietary components. In addition, applicable knowledge of genetic, environmental, and molecular influences on carcinogenesis and the interaction of diet or dietary factors with these aspects are providing an interface for cancer prevention researchers to better assess cancer risk and intervene to reduce risk. The relationship between food and cancer and other chronic diseases, such as cardiovascular disease and diabetes, is tremendously complex. Although much progress has been made in understanding this complexity, it seems apparent that the majority of information remains to be discovered and many challenges exist. Possibly the most important lesson for nutrition research in the past decade has been recognizing the need for a new paradigm for discovering the role of nutrition and diet in disease prevention (Greenwald, 2001). This new approach will, by necessity, be more interdisciplinary and will incorporate advances in molecular biology, genetics, metabolic studies, and various other disciplines with clinical trials. By encompassing and integrating lifestyle and medical approaches, cancer prevention researchers will broaden the scope of research activities to develop compelling strategies to improve the public health. Understanding individual variability through enhanced use of emerging technologies and identification of risk profiles to target those who could benefit from lifestyle or medical interventions will fill the need for better research translation.

The new paradigm in nutritional oncology is developing in an environment of change in many fields of science. Advances in our understanding of the changes in the genetic and epigenetic environments after exposure to foods is driving the search for molecular targets and mechanisms that can be altered by dietary modifications, either alone or combined with other lifestyle choices. Along with new approaches to nutritional oncology, new terms have been developed to describe interactions among foods, genes, proteins, and cells (see Box 1). The interrelationships between bioactive food components (BFCs) and cellular processes, as currently understood, are depicted in Figure 1.

BOX 1 Nutritional Oncology Terminology

Bioactive Food Components

Compounds within foods that have a direct or indirect action on genetic or epigenetic structures and/or processes Genomics

The study of genes and their functions

Nutrigenomics

The prospective analysis of differences among nutrients regarding the regulation of gene expression

Nutrigenetics

The genetic profile that influences absorption, metabolism, and site of action of the response of genes to bioactive food components Epigenomics

The study of heritable changes in gene function that cannot be explained by changes in DNA sequence.

Proteomics

The study of protein shape, function, and patterns of expression

Metabolomics

The study of low-molecular-weight fractions of cells, tissues, and body fluids

FIGURE 1 The interrelationship of factors that can influence the overall response to food components.

Nutritional oncology encompasses prevention of cancer in healthy individuals, prevention of recurring cancer in cancer survivors, and the impact of nutrition among patients undergoing treatment for cancer. Each of these areas is the focus of ongoing research as the role of nutrition in the cancer spectrum of prevention, screening and detection, diagnosis, treatment, and palliative care is determined and strategies developed. There are differences in the approach to nutritional intervention at each step of the spectrum, and health professionals should be aware of differences in recommending dietary or other lifestyle changes, especially before, during, and after cancer treatment (American Cancer Society, 2001; Shattner, 2003; Lada et al., 2004).

Systematic Approaches to Cancer Prevention

The overall research approach for cancer prevention begins with a systematic assessment of what people are eating, how nutrients and nonnutrient dietary constituents interact within the body, and other aspects of lifestyle—for example, weight gain, obesity, body mass index (BMI), and physical activity—that are affected by nutrition. One systematic approach, and the approach that is used as the template for this chapter, is the three-D (3-D) approach of discovery, development, and delivery (von Eschenbach, 2003). The focus of the 3-D approach is on creating a research environment to integrate disparate research communities in an effort to enhance the search for clues to the diet–cancer link and to speed dissemination of research results to the clinician and the public.

• Discovery is the process that generates new knowledge about fundamental aspects of cancer-related processes at the genetic, molecular, cellular, organ, person, and population levels.

• Development is the process of creating and evaluating tools and interventions to reduce the cancer burden, including the prevention, detection, diagnosis, and treatment of cancer and its sequelae.

• Delivery is the process of disseminating, facilitating and promoting evidence-based prevention, detection, diagnosis, and treatment practices and policies to reduce the burden of cancer in all segments of the population. The focus of these efforts is on populations who bear the greatest burden of disease.

The 3-D approach has been developed as a seamless integrated template for initiating and conducting investigations for cancer prevention, not as a sequential approach most common to past research initiatives. Discovery, development, and delivery will be designed to proceed concurrently, with results from each initiative causing adjustments in each of the other initiatives or creation of new research paths. Investigations include both lifestyle and medical approaches, which have provided important clues to the role of nutrition in cancer risk.

Lifestyle Approaches

Nutrition and diet contribute ∼35% to cancer risk, approximately the same risk contribution as tobacco smoking (Doll and Peto, 1981). An analysis of worldwide cancer incidence and mortality rates suggests that 3–4 million cancer deaths per year are attributable to dietary factors, with a stronger association among cancers that are not hormonally mediated (stomach and colorectal), compared with those that are (breast and prostate) (Young and LeLeu, 2002) (Table 1). Lifestyle approaches to cancer prevention may begin with changing dietary patterns that may be addressed by the complete diet that impacts overall health and cancer, such as obesity. For example, although the U.S. population has decreased the amount of fat in the diet in the past 2 decades, portion sizes (particularly in restaurants), the number of daily calories consumed, the average weight of Americans (especially among adolescents), and the percentage of Americans who are obese have increased. The trend for the increasing prevalence of overweight and obesity is of special concern because of studies that show the negative impact of obesity on cancer risk. In the past decade, the prevalence of overweight (BMI 25.0–29.9) and obesity (BMI ≥30.0) among adults in the United States has increased from 56% to 64% (Flegal et al., 2002). The association between overweight and obesity and a significant risk of cardiovascular mortality has been known for some time; however, the magnitude of the significance for cancer mortality has not been quantified until recently (Calle et al., 1999). A prospective cohort study of more than one million adults in the United States assessed cardiovascular disease mortality and BMI and found a significantly increased risk of death among men (relative risk [RR] = 2.9) and women (RR = 2.37) (Calle et al., 1999). In a subsequent study of cancer mortality in the same cohort, the effect of overweight and obesity was found to contribute to 20% of cancer deaths in women and 14% in men (Calle et al., 2003). For specific cancer sites, there was a lin...

Table of contents

• Cover image
• Title page
• Table of Contents
• EDITOR-IN-CHIEF
• Copyright
• Contributing Authors
• Preface
• Introduction: The Principles of Nutritional Oncology
• I: Biology of Nutrition and Cancer
• II: Epidemiology of Nutrition and Cancer
• III: Biological Approaches to Investigating Nutrition and Cancer
• IV: Gene-Nutrient Interaction and Cancer Prevention
• V: Bioactive Food Components and Botanical Approaches to Cancer
• VI: Nutritional Assessment and Support of the Cancer Patient
• VII: Nutritional Implementation Guidelines and Practice
• Index