Rationale and design of the Diet Restriction and Exercise-induced Adaptations in Metastatic breast cancer (DREAM) study: a 2-arm, parallel-group, phase II, randomized control trial of a short-term, calorie-restricted, and ketogenic diet plus exercise during intravenous chemotherapy versus usual care

Take the bull by the horns and tackle the potential downsides of the ketogenic diet

The ketogenic diet (KD) is a distinctive dietary regimen known for its low-carbohydrate and high-fat composition. Recently, it has garnered considerable interest from the scientific community and the general population because of its claimed efficacy in facilitating weight reduction, improving the management of glucose levels, and raising overall energy levels. The core principle of the KD is the substantial decrease in carbohydrate consumption, which is subsequently substituted by ingesting nourishing fats. While the KD has promising advantages and is gaining popularity, it must be acknowledged that this dietary method may not be appropriate for all individuals. The dietary regimen may give rise to adverse effects, including constipation, halitosis, and imbalances in electrolyte levels, which may pose a potential risk if not adequately supervised. Hence, thorough and meticulous inquiry is needed to better comprehend the possible hazards and advantages linked to the KD over prolonged durations. By obtaining a more comprehensive perspective, we can enhance our ability to make well-informed judgments and suggestions as to implementation of this specific dietary regimen.

Evaluating predictive equations for energy requirements throughout breast cancer trajectory: A comparative study

BACKGROUND & AIMS

Accurately estimating resting energy requirements is crucial for optimizing energy intake, particularly in the context of patients with varying energy needs, such as individuals with cancer. We sought to evaluate the agreement between resting energy expenditure (REE) predicted by 40 equations and that measured by reference methods in women undergoing active breast cancer treatment stage (I-IV) and post-completion (i.e., survivors).

METHODS

Data from 4 studies were combined. REE values estimated from 40 predictive equations identified by a systematic search were compared with REE assessed by indirect calorimetry (IC) using a metabolic cart (MC-REE N = 46) or a whole-room indirect calorimeter (WRIC-REE N = 44). Agreement between methods was evaluated using Bland-Altman and Lin's concordance coefficient correlation (Lin's CCC).

RESULTS

Ninety participants (24 % survivors, 61.1% had early-stage breast cancer I or II, mean age: 56.8 ± 11 years; body mass index: 28.7 ± 6.4 kg/m2) were included in this analysis. Mean MC-REE and WRIC-REE values were 1389 ± 199 kcal/day and 1506 ± 247 kcal/day, respectively. Limits of agreement were wide for all equations compared to both MC and WRIC (∼300 kcal for both methods), including the most commonly used ones, such as Harris-Benedict and Mifflin ST. Jeor equations; none had a bias within ±10% of measured REE, and all had low agreement per Lin's CCC analysis (<0.90). The Korth equation exhibited the best performance against WRIC and the Lvingston-Kohlstadt equation against MC. Similar patterns of bias were observed between survivors and patients and between patients with stages I-III versus IV cancer.

CONCLUSION

Most equations failed to accurately predict REE at the group level, and none were effective at the individual level. This inaccuracy has significant implications for women with or surviving breast cancer, who may experience weight gain, maintenance, or loss due to inaccurate energy needs estimations. Therefore, our research underscores the need for further efforts to improve REE estimation.

Advances in Diet and Physical Activity in Breast Cancer Prevention and Treatment

There is currently a growing interest in diets and physical activity patterns that may be beneficial in preventing and treating breast cancer (BC). Mounting evidence indicates that indeed, the so-called Mediterranean diet (MedDiet) and regular physical activity likely both help reduce the risk of developing BC. For those who have already received a BC diagnosis, these interventions may decrease the risk of tumor recurrence after treatment and improve quality of life. Studies also show the potential of other dietary interventions, including fasting or modified fasting, calorie restriction, ketogenic diets, and vegan or plant-based diets, to enhance the efficacy of BC therapies. In this review article, we discuss the biological rationale for utilizing these dietary interventions and physical activity in BC prevention and treatment. We highlight published and ongoing clinical studies that have applied these lifestyle interventions to BC patients. This review offers valuable insights into the potential application of these dietary interventions and physical activity as complimentary therapies in BC management.

Clinical implications of nutritional interventions reducing calories, a systematic scoping review

BACKGROUND & AIMS

Caloric restriction (CR) constitutes a dietary approach of (temporarily) reducing calorie intake thereby inducing resilience and resistance mechanisms and promoting health. While CR's feasibility and safety have been proven in human trials, its full benefits and translation to different study populations warrants further exploration.

METHODS

We here conducted a systematic scoping review adhering to Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines.

RESULTS

Our search resulted in 3745 individual records, of which 40 were included. We showed that all studies consistently demonstrated the feasibility and safety of CR-like interventions. The specific effects of nutritional preconditioning vary, further underscoring the need for carefully crafted strategies, according to the intended effect, patient population, and logistical limitations.

CONCLUSIONS

CR-like interventions (long-term CR or short-term fasting) are feasible in a broad range of patient populations. Whether it has clinical benefit, f.i. reducing treatment-induced side effects and enhancing therapy efficacy, has to be investigated further.

Caloric restriction for the management of malignant tumors - from animal studies towards clinical translation

In the last few years, numerous studies have demonstrated that dietary modifications in the form of calory restriction exert beneficial effects in several clinical entities, including aging-related pathologies, autoimmune diseases and cancer. Both as preventive but also as therapeutic modalities, these dietary regimens can impact systemic metabolism, immune and hormonal responses, redox balance and gut microbiota, among others. In the field of oncology, the vast majority of experimental work has explored the role of restricted diets in the prevention of malignant tumors, mostly in carcinogenesis-induced models, with at least encouraging results; on the contrary, less research has been performed in the management of full-blown cancer with ketogenic diet or caloric restriction protocols. Herein, we are aiming to review the relevant preclinical and clinical studies to date that investigate the role of caloric restriction in the treatment of established cancer.

Common and divergent molecular mechanisms of fasting and ketogenic diets

Intermittent short-term fasting (ISTF) and ketogenic diets (KDs) exert overlapping but not identical effects on cell metabolism, function, and resilience. Whereas health benefits of KD are largely mediated by the ketone bodies (KBs), ISTF engages additional adaptive physiological responses. KDs act mainly through inhibition of histone deacetylases (HDACs), reduction of oxidative stress, improvement of mitochondria efficiency, and control of inflammation. Mechanisms of action of ISTF include stimulation of autophagy, increased insulin and leptin sensitivity, activation of AMP-activated protein kinase (AMPK), inhibition of the mechanistic target of rapamycin (mTOR) pathway, bolstering mitochondrial resilience, and suppression of oxidative stress and inflammation. Frequent switching between ketogenic and nonketogenic states may optimize health by increasing stress resistance, while also enhancing cell plasticity and functionality.

Diet-driven microbiome changes and physical activity in cancer patients

Exploring the role of the gut microbiome in oncology is gaining more attention, mainly due to its ability to shape the immune system in cancer patients. A well-balanced microbial composition forms a symbiotic relationship with the host organism. Mounting evidence supports the potential of modifiable lifestyle factors, such as diet and physical activity, in restoring intestinal dysbiosis related to cancer development and treatment. In this Minireview, we describe the host-microbiome interplay following different dietary patterns, including a high-fat diet, fiber-rich diet, diet rich in rice and beans, Mediterranean diet, ketogenic diet, and physical activity in preclinical findings and clinical settings. According to the results, nutrition is a critical factor influencing the composition of gut microbial communities. Therefore, knowledge about the patient's nutritional status in pre-treatment and treatment becomes crucial for further management. A combination of individualized dietary habits and professional training plans might help to maintain gut homeostasis, potentially improving the response to anti-cancer therapy and the quality of life in cancer survivors. However, a deep understanding of underlying mechanisms and large clinical trials are needed to uncover clinically relevant correlations for personalized treatment approaches leading to better outcomes for cancer patients.

Ketogenic diet in cancer management

PURPOSE OF REVIEW

This review presents details about types of ketogenic diet (KD), anticancer mechanisms, and the use of KD in experimental and clinical studies. Studies summarized in this review provide a solid ground for researchers to consider the use of KD to augment conventional treatments.

RECENT FINDINGS

KD is a dietary pattern composed of high fat, moderate proteins, and very-low-carbohydrate. This diet was suggested to have an anticancer effect and to augment conventional anticancer therapies. KD can target cancer cell by interfering with its metabolism without harming normal cells.

SUMMARY

Several experimental and clinical studies support the use of KD as adjuvant therapy to treat different cancers.

Web-based nutrition: a useful resource for cancer patients?

Introduction

An accessible and affordable way to deliver behavior change programs to a large proportion of the growing community of cancer patients and survivors is through web-based methods of nutritional counselling.

Objective

The aim of this systematic review was to evaluate the effectiveness of web-based nutritional therapies targeting physical activity, diet, and/or weight control for cancer patients or survivors, primarily disseminated via modern technologies (mobile phone applications) or online.

Materials and methods

The authors conducted a structured search of the PubMed database. Studies that have focused on physical activity (PA) and dietary change and/or weight control in adolescent and adult cancer patients and survivors have reported outcomes conducted via a broad modality.

Results

Nine articles focused on web-based nutrition for patients with cancer and cancer survivors. They were conducted in the United States, Australia, Korea, China, and in the United Kingdom, and were published between 2018 and 2022 in a variety of scientific journals. The number of participants ranged from 20 to 159.

Conclusion

Web-based nutrition counselling helps cancer patients and survivors improve their dietary intake, impacts their weight and quality of life, and promotes a healthy lifestyle. Future research should evaluate (1) the differences in cost and coverage between face-to-face and web-based nutrition, (2) long-term outcomes, (3) cost-effectiveness, and last but not least, (4) the effectiveness of web-based nutrition in adolescents and children who suffer from cancer or who survived cancer, as nutritional status and body composition have a marked impact on clinical outcomes during and after treatment. The strength of this review lies in the large number of randomized controlled trials, which offer a guarantee of effectiveness and objectivity compared to cross-sectional studies.

Effects of Obesity and Calorie Restriction on Cancer Development

The risk of malignant tumor development is increasing in the world. Obesity is an established risk factor for various malignancies. There are many metabolic alterations associated with obesity which promote cancerogenesis. Excessive body weight leads to increased levels of estrogens, chronic inflammation and hypoxia, which can play an important role in the development of malignancies. It is proved that calorie restriction can improve the state of patients with various diseases. Decreased calorie uptake influences lipid, carbohydrate and protein metabolism, hormone levels and cell processes. Many investigations have been devoted to the effects of calorie restriction on cancer development in vitro and in vivo. It was revealed that fasting can regulate the activity of the signal cascades including AMP-activated protein kinase (AMPK), mitogen-activated protein kinase (MAPK), p53, mTOR, insulin/ insulin-like growth factor 1 (IGF1) and JAK-STAT. Up- or down-regulation of the pathways results in the decrease of cancer cell proliferation, migration and survival and the increase of apoptosis and effects of chemotherapy. The aim of this review is to discuss the connection between obesity and cancer development and the mechanisms of calorie restriction influence on cancerogenesis that stress the importance of further research of calorie restriction effects for the inclusion of this approach in clinical practice.

Qigong Exercise Balances Oxygen Supply and Acid-Base to Modulate Hypoxia: A Perspective Platform toward Preemptive Health & Medicine

Qigong is a meditative movement with therapeutic effects and is commonly practiced in Eastern medicine. A growing body of evidence validates its health benefits, leading to mechanistic questions about how it works. We propose a novel mechanism by which the “acid” caused by hypoxia affects metabolism, and the way it is neutralized through Qigong practice involves the body’s blood flow and vasculature modifications. Specifically, Qigong exercise generates an oxygen supply and acid-base balance against the hypoxic effects of underlying pathological conditions. We also propose that Qigong exercise mediated and focused on the local hypoxia environment of tissues might normalize the circulation of metabolic and inflammation accumulation in the tumor tissue and restore the normal metabolism of tissues and cells through calm, relaxation, and extreme Zen-style breathing that gravitates toward preemptive health and medicine. Thus, we propose the mechanisms of action related to Qigong, intending to unify Eastern and Western exercise theory.

Monitoring and Modulating Diet and Gut Microbes to Enhance Response and Reduce Toxicity to Cancer Treatment

The gut microbiome comprises a diverse array of microbial species that have been shown to dynamically modulate host immunity both locally and systemically, as well as contribute to tumorigenesis. In this review, we discuss the scientific evidence on the role that gut microbes and diet play in response and toxicity to cancer treatment. We highlight studies across multiple cancer cohorts that have shown an association between particular gut microbiome signatures and an improved response to immune checkpoint blockade, chemotherapy, and adoptive cell therapies, as well as the role of particular microbes in driving treatment-related toxicity and how the microbiome can be modulated through strategies, such as fecal transplant. We also summarize the current literature that implicate high fiber and ketogenic diets in improved response rates to immunotherapy and chemotherapy, respectively. Finally, we discuss the relevance of these findings in the context of patient care, advocate for a holistic approach to cancer treatment, and comment on the next frontier of targeted gut and tumor microbiome modulation through novel therapeutics, dietary intervention, and precision-medicine approaches.

Facts and Perspectives: Implications of tumor glycolysis on immunotherapy response in triple negative breast cancer

Triple negative breast cancer (TNBC) is an aggressive disease that is difficult to treat and portends a poor prognosis in many patients. Recent efforts to implement immune checkpoint inhibitors into the treatment landscape of TNBC have led to improved outcomes in a subset of patients both in the early stage and metastatic settings. However, a large portion of patients with TNBC remain resistant to immune checkpoint inhibitors and have limited treatment options beyond cytotoxic chemotherapy. The interplay between the anti-tumor immune response and tumor metabolism contributes to immunotherapy response in the preclinical setting, and likely in the clinical setting as well. Specifically, tumor glycolysis and lactate production influence the tumor immune microenvironment through creation of metabolic competition with infiltrating immune cells, which impacts response to immune checkpoint blockade. In this review, we will focus on how glucose metabolism within TNBC tumors influences the response to immune checkpoint blockade and potential ways of harnessing this information to improve clinical outcomes.

Fast Mimicking Diets and Other Innovative Nutritional Interventions to Treat Patients with Breast Cancer

The impact of nutritional patterns on the risk of breast cancer (BC) is well investigated in the oncology literature, including the type of diets and caloric intake. While obesity and elevated body mass index are well-reported critical risk factors of BC occurrence, there is an expanding area of oncology assessing the impact of caloric intake and nutritional patterns in patients with cancer. Caloric restriction and fast mimicking alimentary regimens have been consistently reported to improve survival outcomes based on preclinical models. Moreover, emerging clinical evidence has paved the way for new metabolic approaches for the treatment of BC, in addition to the established therapeutic arsenal or as alternative options. In this chapter, our aim is to discuss the principal strategies of metabolic manipulation through nutritional interventions for patients with BC as an innovative area of cancer therapy.

The role of lipid metabolic reprogramming in tumor microenvironment

Metabolic reprogramming is one of the most important hallmarks of malignant tumors. Specifically, lipid metabolic reprogramming has marked impacts on cancer progression and therapeutic response by remodeling the tumor microenvironment (TME). In the past few decades, immunotherapy has revolutionized the treatment landscape for advanced cancers. Lipid metabolic reprogramming plays pivotal role in regulating the immune microenvironment and response to cancer immunotherapy. Here, we systematically reviewed the characteristics, mechanism, and role of lipid metabolic reprogramming in tumor and immune cells in the TME, appraised the effects of various cell death modes (specifically ferroptosis) on lipid metabolism, and summarized the antitumor therapies targeting lipid metabolism. Overall, lipid metabolic reprogramming has profound effects on cancer immunotherapy by regulating the immune microenvironment; therefore, targeting lipid metabolic reprogramming may lead to the development of innovative clinical applications including sensitizing immunotherapy.

The Ketogenic Diet: Considerations for Cancer Survivorship

PURPOSE OF REVIEW

This article aims to evaluate the current practice of the ketogenic diet (KD) in oncology by discussing feasibility, impact on quality of life, and implications for dietetic practice. Articles discussed were selected based on an adult oncology population with emphasis on publications from the last 5 years.

RECENT FINDINGS

There is a paucity of randomized prospective trials and articles reviewed were heterogeneous in nature, limiting the ability to draw conclusions about the KDs role in cancer care and survivorship. Despite the lack of evidence, patients with cancer are interested in KD. The authors highlight barriers to supporting implementation of KD and recommend the inclusion of a registered dietitian with experience in KD to ensure safety and support the nutrition goals of patients with cancer. Thorough, well-designed randomized control trials are needed to elucidate the potential advantages of this diet therapy in cancer care and survivorship.

Phytochemical Targeting of Mitochondria for Breast Cancer Chemoprevention, Therapy, and Sensitization

Breast cancer is a common and deadly disease that causes tremendous physical, emotional, and financial burden on patients and society. Early-stage breast cancer and less aggressive subtypes have promising prognosis for patients, but in aggressive subtypes, and as cancers progress, treatment options and responses diminish, dramatically decreasing survival. Plants are nutritionally rich and biologically diverse organisms containing thousands of metabolites, some of which have chemopreventive, therapeutic, and sensitizing properties, providing a rich source for drug discovery. In this study we review the current landscape of breast cancer with a central focus on the potential role of phytochemicals for treatment, management, and disease prevention. We discuss the relevance of phytochemical targeting of mitochondria for improved anti-breast cancer efficacy. We highlight current applications of phytochemicals and derivative structures that display anti-cancer properties and modulate cancer mitochondria, while describing future applicability and identifying areas of promise.

Exercise as cancer treatment: A clinical oncology framework for exercise oncology research

Exercise has been proposed as a possible cancer treatment; however, there are an infinite number of clinical oncology settings involving diverse cancer types and treatment protocols in which exercise could be tested as a cancer treatment. The primary purpose of this paper is to propose a conceptual framework to organize and guide research on exercise as a cancer treatment across distinct clinical oncology settings. A secondary purpose is to provide an overview of existing exercise research using the proposed framework. The Exercise as Cancer Treatment (EXACT) framework proposes nine distinct clinical oncology scenarios based on tumor/disease status and treatment status at the time of the proposed exercise treatment. In terms of tumor/disease status, the primary tumor has either been surgically removed (primary goal to treat micrometastases), not surgically removed (primary goal to treat the primary tumor), or metastatic disease is present (primary goal to treat metastatic disease). In terms of treatment status, the extant disease has either not been treated yet (treatment naïve), is currently being treated (active treatment), or has previously been treated. These two key clinical oncology variables—tumor/disease status and treatment status—result in nine distinct clinical oncology scenarios in which exercise could be tested as a new cancer treatment: (a) treatment naïve micrometastases, (b) actively treated micrometastases, (c) previously treated micrometastases, (d) treatment naïve primary tumors, (e) actively treated primary tumors, (f) previously treated primary tumors, (g) treatment naïve metastatic disease, (h) actively treated metastatic disease, and (i) previously treated metastatic disease. To date, most preclinical animal studies have examined the effects of exercise on treatment naïve and actively treated primary tumors. Conversely, most observational human studies have examined the associations between exercise and cancer recurrence/survival in patients actively treated or previously treated for micrometastases. Few clinical trials have been conducted in any of these scenarios. For exercise to be integrated into clinical oncology practice as a cancer treatment, it will need to demonstrate benefit in a specific clinical setting. The EXACT framework provides a simple taxonomy for systematically evaluating exercise as a potential cancer treatment across a diverse range of cancer types and treatment protocols.

Insulin-Lowering Diets in Metastatic Cancer

Hyperinsulinemia is an independent risk factor for cancer mortality. Insulin-lowering dietary strategies such as calorie restriction (CR), low-carbohydrate or ketogenic diets (KD), and intermittent fasting (IF) are aimed at reducing systemic stores of nutrients utilized by cancer cells, attenuating insulin-related growth signaling, and improving obesity-related metabolic parameters. In this narrative review, we searched the published literature for studies that tested various insulin-lowering diets in metastatic cancer in preclinical and clinical settings. A total of 23 studies were identified. Of these, 14 were preclinical studies of dietary strategies that demonstrated improvements in insulin levels, inhibition of metastasis, and/or reduction in metastatic disease burden in animal models. The remaining nine clinical studies tested carbohydrate restriction, KD, or IF strategies which appear to be safe and feasible in patients with metastatic cancer. These approaches have also been shown to improve serum insulin and other metabolic parameters. Though promising, the anti-cancer efficacy of these interventions, such as impact on tumor response, disease-specific-, and overall survival, have not yet been conclusively demonstrated. Studies that are adequately powered to evaluate whether insulin-lowering diets improve cancer outcomes are warranted.

Calorie restriction and breast cancer treatment: a mini-review

Calorie restriction (CR), referred to as a reduction in dietary calorie intake without malnutrition, has been demonstrated to be a safe way to extend longevity of yeast, worms, and laboratory animals, and to decrease the risk factors in age-related diseases including cancer in humans. Pre-clinical studies in animal models demonstrated that CR may enhance the efficacy of chemotherapy, radiation therapy, and immunotherapy during breast cancer treatment. Reduced calorie intake ameliorates risk factors and delays the onset of cancer by altering metabolism and fostering health-enhancing characteristics including increased autophagy and insulin sensitivity, and decreased blood glucose levels, inflammation, angiogenesis, and growth factor signaling. CR is not a common protocol implemented by medical practitioners to the general public due to the lack of substantial clinical studies. Future research and clinical trials are urgently needed to understand fully the biochemical basis of CR or CR mimetics to support its benefits. Here, we present a mini-review of research studies integrating CR as an adjuvant to chemotherapy, radiation therapy, or immunotherapy during breast cancer treatment.

The non-fatal burden of cancer in Belgium, 2004-2019: a nationwide registry-based study

BACKGROUND

The importance of assessing and monitoring the health status of a population has grown in the last decades. Consistent and high quality data on the morbidity and mortality impact of a disease represent the key element for this assessment. Being increasingly used in global and national burden of diseases (BoD) studies, the Disability-Adjusted Life Year (DALY) is an indicator that combines healthy life years lost due to living with disease (Years Lived with Disability; YLD) and due to dying prematurely (Years of Life Lost; YLL). As a step towards a comprehensive national burden of disease study, this study aims to estimate the non-fatal burden of cancer in Belgium using national data.

METHODS

We estimated the Belgian cancer burden from 2004 to 2019 in terms of YLD, using national population-based cancer registry data and international disease models. We developed a microsimulation model to translate incidence- into prevalence-based estimates, and used expert elicitation to integrate the long-term impact of increased disability due to surgical treatment.

RESULTS

The age-standardized non-fatal burden of cancer increased from 2004 to 2019 by 6 and 3% respectively for incidence- and prevalence-based YLDs. In 2019, in Belgium, breast cancer had the highest morbidity impact among women, followed by colorectal and non-melanoma skin cancer. Among men, prostate cancer had the highest morbidity impact, followed by colorectal and non-melanoma skin cancer. Between 2004 and 2019, non-melanoma skin cancer significantly increased for both sexes in terms of age-standardized incidence-based YLD per 100,000, from 49 to 111 for men and from 15 to 44 for women. Important decreases were seen for colorectal cancer for both sexes in terms of age-standardized incidence-based YLD per 100,000, from 105 to 84 for men and from 66 to 58 for women.

CONCLUSIONS

Breast and prostate cancers represent the greatest proportion of cancer morbidity, while for both sexes the morbidity burden of skin cancer has shown an important increase from 2004 onwards. Integrating the current study in the Belgian national burden of disease study will allow monitoring of the burden of cancer over time, highlighting new trends and assessing the impact of public health policies.