Anticancer restrictive diets and the risk of psychological distress: Review and perspectives.

INTRODUCTION: The most studied anticancer restrictive diets include fasting, fasting-mimicking diets (FMDs) and ketogenic diets (KDs). Besides the current lack of established clinical benefit and the significant risk of malnutrition and micronutrient deficiencies, dietary restrictions in cancer patients might have relevant psychological effects. MATERIALS AND METHODS: We reviewed the randomized and non-randomized controlled clinical trials (CCTs) reporting data on the psychological impact of fasting, FMDs and KDs in cancer patients. We excluded trials on restrictive diets performed for weight reduction in obese or overweight patients, studies on dietary restrictions lasting less than 24 h, and studies on fasting related to cultural or religious beliefs. RESULTS: Three CCTs on fasting or FMDs and eight CCTs on KDs in cancer patients were included. In terms of diet-related distress, emotional, social, and family well-being, none of these studies showed a detrimental impact of fasting, FMDs and KDs. However, clinical trials specifically assessing the psychological aspects in the long term are lacking. CONCLUSIONS AND PERSPECTIVES: In the absence of a conclusive evidence on the clinical benefits of restrictive diets, which carry significant risks especially if unsupervised, further studies are needed to clarify their psychological impact in cancer patients. Multidisciplinary approaches including psychological evaluations should be used to ameliorate patient selection for clinical trials, identify early distress symptoms, and increase patient compliance to dietary recommendations.

Dietary intervention for adult survivors of cancers other than breast cancer: A systematic review.

INTRODUCTION: Healthy eating and weight control are recommended for cancer survivors; however, dietary interventions are not routinely offered to them. This study aimed to assess the effects of dietary interventions on survival, nutritional status, morbidity, dietary changes, health-related quality of life (QOL), and clinical measures in cancer survivors. METHODS: Searches were conducted from October 1, 2018 to November 21, 2011 in the Medline, EMBASE, CENTRAL, Emcare, and DARE electronic databases. We included randomized controlled trials (RCTs) that involved individuals diagnosed with cancer, excluding conference abstracts, case studies, other reviews, and meta-analyses, and screened the articles. RESULTS: Eight studies were included in this meta-analysis. We observed significant improvements in QOL and clinical data in 3 of 6 studies and in one study, respectively, significant weight loss on anthropometry in 2 of 5 studies, and dietary improvement in 4 of 5 studies of adult cancer survivors. However, we did not observe any benefits of dietary intervention for cancer survivors with undernutrition. DISCUSSION: Dietary interventions for adult cancer survivors might contribute to improving their nutritional status; however, further clarification requires a study that standardizes the intervention method. Furthermore, RCTs are required to determine the effects on cancer survivors with undernutrition.

Exploring dietitians' practice and perspectives on the role of dietary patterns during cancer treatment: A qualitative study.

BACKGROUND: Dietitians are nutrition professionals equipped with specialised skills required to prevent and treat malnutrition in cancer. Optimisation of dietary intake is recommended as the primary nutrition strategy for the treatment of cancer-related malnutrition. However, it is unclear whether dietary patterns, described as the combination, quantity, and frequency of food consumption, are considered. This study examined dietitians' current food-based management of malnutrition; explored dietitians' awareness of dietary patterns and assessed barriers and enablers to the use of dietary patterns in clinical practice. METHODS: This qualitative study consisted of semi-structured interviews with oncology dietitians. Dietitians were recruited through national nutrition societies, social media, and professional networks. Audio-recorded interviews were transcribed verbatim and analysed using inductive thematic analysis. RESULTS: Fourteen oncology dietitians from across four Australian states and territories participated. Three themes were identified: (i) principles to guide nutritional care, (ii) dietary patterns as a gap in knowledge and practice, and (iii) opportunities for better care with systems as both a barrier and enabler. Dietetic practice was food-focussed, encouraging energy and protein-rich foods consistent with nutrient-focussed evidence-based guidelines. Dietitians encouraged one of two nutrition-related approaches, either encouraging intake of 'any tolerated food' or 'foods supportive on longer-term health'. Dietitians were generally unaware of dietary patterns and questioned their relevance in certain clinical situations. A multidisciplinary team approach, adequate food service and dissemination of dietary patterns research and education were identified as opportunities for better patient care. CONCLUSIONS: Recommendations for the treatment of malnutrition vary between oncology dietitians and uncertainty exists regarding dietary patterns and their relevance in clinical practice. Further exploration into the role of dietary patterns to treat cancer-related malnutrition and education for dietitians are required prior to implementation of a dietary patterns approach into clinical practice.

A Phase I Trial of a Methionine Restricted Diet with Concurrent Radiation Therapy.

Methionine is an essential amino acid critical for cell growth and survival. Preclinical evidence suggests a methionine restricted diet (MRD) sensitizes cancer to radiation therapy (RT), without significant adverse effects. However, this has never been evaluated in humans. The purpose of this pilot study was to evaluate the safety and feasibility of concurrent MRD with standard-of-care definitive RT in adults with any non-skin cancer malignancy. The MRD extended from 2 wk before RT initiation, through 2 wk beyond RT completion. The primary endpoint of safety was assessed as rate of grade 3 or higher acute and late toxicities. Feasibility was assessed with quantitative plasma amino acid panel every 2 wk during the MRD (target plasma methionine 13 µM). Nine patients were accrued over a two-year period, with five able to complete the treatment course. The trial was closed due to slow accrual and subjects' difficulty maintaining the diet. No grade 3 or higher adverse events were observed. Subjects' average methionine level was 18.8 µM during treatment, with average nadir 16.8 µM. These findings suggest the safety of concurrent MRD with RT, with toxicities comparable to those expected with RT alone. However, the diet was challenging, and unacceptable to most patients.

Dietary interventions in cancer: a systematic review of all randomized controlled trials.

BACKGROUND: Prior systematic reviews addressing the impact of diet on cancer outcomes have focused on specific dietary interventions. In this systematic review, we assessed all randomized controlled trials (RCTs) investigating dietary interventions for cancer patients, examining the range of interventions, endpoints, patient populations, and results. METHODS: This systematic review identified all RCTs conducted before January 2023 testing dietary interventions in patients with cancer. Assessed outcomes included quality of life, functional outcomes, clinical cancer measurements (eg, progression-free survival, response rates), overall survival, and translational endpoints (eg, inflammatory markers). RESULTS: In total, 252 RCTs were identified involving 31 067 patients. The median sample size was 71 (interquartile range 41 to 118), and 80 (32%) studies had a sample size greater than 100. Most trials (n = 184, 73%) were conducted in the adjuvant setting. Weight or body composition and translational endpoints were the most common primary endpoints (n = 64, 25%; n = 52, 21%, respectively). Direct cancer measurements and overall survival were primary endpoints in 20 (8%) and 7 (3%) studies, respectively. Eight trials with a primary endpoint of cancer measurement (40%) met their endpoint. Large trials in colon (n = 1429), breast (n = 3088), and prostate cancer (n = 478) each showed no effect of dietary interventions on endpoints measuring cancer. CONCLUSION: Most RCTs of dietary interventions in cancer are small and measure nonclinical endpoints. Although only a small number of large RCTs have been conducted to date, these trials have not shown an improvement in cancer outcomes. Currently, there is limited evidence to support dietary interventions as a therapeutic tool in cancer care.

Mediterranean-style dietary interventions in adults with cancer: a systematic review of the methodological approaches, feasibility, and preliminary efficacy.

BACKGROUND: Cancer and its treatments can lead to excess body fat, decreases in lean mass, cardiotoxicity, and other side effects. The Mediterranean diet (MED-diet) has the potential to improve clinical and supportive care outcomes. The aim of this systematic review was to evaluate the feasibility, safety, and efficacy of the MED-diet on health outcomes in adults with cancer. METHODS: Three databases were searched from inception to February 2023. Eligible studies included randomised controlled trials testing a MED-diet intervention among adults with cancer. Within- and between-group differences for adherence, dietary intake and health outcomes were extracted. RESULTS: Fifteen studies describing fourteen interventions were included, and there were considerable differences in study design and implementation of the MED-diet. Studies were predominately in women with a history of breast cancer. The MED-diet was safe with no adverse events reported, and feasible with high adherence and/or increases in MED-diet-compliant foods. The MED-diet when applied with an energy restriction below estimated requirements for weight loss demonstrated reductions in body weight (range: -3.9 kg to -0.7 kg). Interventions that showed significant reductions in body weight also improved quality of life. There is limited evidence to evaluating the MED-diet on cardiovascular and inflammatory markers, and heterogenous MED-diet prescriptions impede definitive conclusions on these health outcomes. CONCLUSION: The MED-diet was feasible and safe for adults with cancer. There were reported benefits for weight loss following a MED-diet when an energy restriction was applied, however further evaluation to determine the effects on cardiometabolic biomarkers and other outcomes are required.

Use of neutropenic diet in the nutritional care of pediatric cancer patients with neutropenia: a scoping review.

OBJECTIVE: to carry out a scoping review with the purpose of mapping the scientific evidence on the use of the neutropenic diet in neutropenic pediatric cancer patients. SOURCE OF DATA: The scoping review protocol was prepared in accordance with the PRISMA-ScR and the checklist before the literature search was performed. Articles on nutritional management in adults or on the treatment of other diseases, and articles that were not in Portuguese or English and published before the year 2000, were excluded. Data were extracted based on the Cochrane Consumer and Communication Review Group form. SUMMARY OF THE FINDINGS: Three hundred and forty scientific articles were identified, with the final sample of this review consisting of nine studies. Although the neutropenic diet has been part of the nutritional management of pediatric cancer patients for more than 20 years, there is still great variation in the criteria for indicating use and starting and discontinuing it, as well as in the nutritional composition of the diet. Furthermore, there is no consensus on the impact of using a neutropenic diet on different clinical and nutritional outcomes. CONCLUSION: In the absence of guidelines that standardize the use of a neutropenic diet in pediatric patients with neutropenia, there are heterogeneous approaches reported in the literature, even within the same institution. The available literature presents an absence of evidence on the use, viability, and effectiveness of the neutropenic diet in oncological children with neutropenia. More studies are needed to identify the real impact of the neutropenic diet on clinical and nutritional outcomes.

Trans-vaccenic acid reprograms CD8+ T cells and anti-tumour immunity.

Diet-derived nutrients are inextricably linked to human physiology by providing energy and biosynthetic building blocks and by functioning as regulatory molecules. However, the mechanisms by which circulating nutrients in the human body influence specific physiological processes remain largely unknown. Here we use a blood nutrient compound library-based screening approach to demonstrate that dietary trans-vaccenic acid (TVA) directly promotes effector CD8+ T cell function and anti-tumour immunity in vivo. TVA is the predominant form of trans-fatty acids enriched in human milk, but the human body cannot produce TVA endogenously1. Circulating TVA in humans is mainly from ruminant-derived foods including beef, lamb and dairy products such as milk and butter2,3, but only around 19% or 12% of dietary TVA is converted to rumenic acid by humans or mice, respectively4,5. Mechanistically, TVA inactivates the cell-surface receptor GPR43, an immunomodulatory G protein-coupled receptor activated by its short-chain fatty acid ligands6-8. TVA thus antagonizes the short-chain fatty acid agonists of GPR43, leading to activation of the cAMP-PKA-CREB axis for enhanced CD8+ T cell function. These findings reveal that diet-derived TVA represents a mechanism for host-extrinsic reprogramming of CD8+ T cells as opposed to the intrahost gut microbiota-derived short-chain fatty acids. TVA thus has translational potential for the treatment of tumours.

Critical evaluation and comparison of nutritional clinical practice guidelines for cancer patients.

BACKGROUND: The growing incidence of cancer globally, and the importance of nutrition support for these patients, emphasize the need for the development of nutritional clinical practice guidelines and consensus papers (CPGs) in the field. Numerous relevant CPGs have been published by several organizations worldwide. The aim of this systematic review was to compare the content of the existing CPGs and evaluate the quality of their development using the AGREE-II tool. METHODS: A systematic literature search in PubMed, Embase and Web of Science databases was conducted for the identification of relevant CPGs and consensus papers. Eligible CPGs was blindly evaluated by four appraisers according to the Appraisal of Guidelines for Research and Evaluation ΙΙ (AGREE-II) tool. RESULTS: In total 15 CPGs were identified and were evaluated. All but one set of CPGs underlined the importance of nutritional screening and assessment, whereas recommendations on nutritional interventions, supplements, management of complications and nutritional follow-up were also reported by several organizations. AGREE-II results showed that two CPGs were characterized as high, eight as moderate and five as low regarding their quality of development. CONCLUSIONS: Variety on recommendations could be observed between CPGs that should be considered when applied into clinical practice. Limitations of the existing CPGs could be the fact that they are non-specific and only a minority of them are focused to specific cancer types. Frequent updates for CPGs and inclusion of more nutritional topics should be considered for some CPGs. Improvement of the quality of the CPGs development should also be pursued in future.

Exceptional tumour responses to fasting-mimicking diet combined with standard anticancer therapies: A sub-analysis of the NCT03340935 trial.

BACKGROUND: Cyclic fasting or calorie-restricted, low-carbohydrate, low-protein diets, collectively referred to as fasting-mimicking diets (FMDs), demonstrated additive or synergistic antitumour effects when combined with chemotherapy, targeted therapies, or immunotherapy in several preclinical in vivo models, including murine models of breast cancer, lung cancer, and colorectal cancer. However, no data on the antitumour efficacy of cyclic FMD in patients with cancer have been published so far. Here, we aim at reporting on patients with advanced cancer achieving complete and long-lasting tumour remissions with cyclic FMD in combination with standard anticancer therapies in the context of the phase Ib NCT03340935 trial. PATIENTS AND METHODS: The NCT03340935 trial enrolled 101 patients with different tumour types, and it showed that a severely calorie-restricted FMD regimen is safe and feasible in patients with cancer receiving concomitant standard-of-care antineoplastic therapies. In addition, cyclic FMD resulted in positive metabolic and immunologic modifications, thus recapitulating the biological effects that in preclinical models were found to mediate the antitumour effects of fasting/FMD. RESULTS: Of the 101 patients enrolled in the NCT03340935 trial, we identified five patients with advanced, poor prognosis solid neoplasms (n = 1: extensive stage small cell lung cancer; n = 1: metastatic pancreatic adenocarcinoma; n = 1: metastatic colorectal cancer; n = 2: metastatic triple-negative breast cancer), who achieved complete and long-lasting tumour responses when treated with a combination of cyclic FMD and standard systemic treatments in the context of the NCT03340935 trial. CONCLUSION: These excellent responses prompt the initiation of clinical trials to investigate cyclic FMD in combination with standard antitumour therapies in specific clinical contexts.

Ketogenic diet for human diseases: the underlying mechanisms and potential for clinical implementations.

The ketogenic diet (KD) is a high-fat, adequate-protein, and very-low-carbohydrate diet regimen that mimics the metabolism of the fasting state to induce the production of ketone bodies. The KD has long been established as a remarkably successful dietary approach for the treatment of intractable epilepsy and has increasingly garnered research attention rapidly in the past decade, subject to emerging evidence of the promising therapeutic potential of the KD for various diseases, besides epilepsy, from obesity to malignancies. In this review, we summarize the experimental and/or clinical evidence of the efficacy and safety of the KD in different diseases, and discuss the possible mechanisms of action based on recent advances in understanding the influence of the KD at the cellular and molecular levels. We emphasize that the KD may function through multiple mechanisms, which remain to be further elucidated. The challenges and future directions for the clinical implementation of the KD in the treatment of a spectrum of diseases have been discussed. We suggest that, with encouraging evidence of therapeutic effects and increasing insights into the mechanisms of action, randomized controlled trials should be conducted to elucidate a foundation for the clinical use of the KD.

Leucine-Rich Diet Improved Muscle Function in Cachectic Walker 256 Tumour-Bearing Wistar Rats.

Skeletal muscle atrophy occurs in several pathological conditions, such as cancer, especially during cancer-induced cachexia. This condition is associated with increased morbidity and poor treatment response, decreased quality of life, and increased mortality in cancer patients. A leucine-rich diet could be used as a coadjutant therapy to prevent muscle atrophy in patients suffering from cancer cachexia. Besides muscle atrophy, muscle function loss is even more important to patient quality of life. Therefore, this study aimed to investigate the potential beneficial effects of leucine supplementation on whole-body functional/movement properties, as well as some markers of muscle breakdown and inflammatory status. Adult Wistar rats were randomly distributed into four experimental groups. Two groups were fed with a control diet (18% protein): Control (C) and Walker 256 tumour-bearing (W), and two other groups were fed with a leucine-rich diet (18% protein + 3% leucine): Leucine Control (L) and Leucine Walker 256 tumour-bearing (LW). A functional analysis (walking, behaviour, and strength tests) was performed before and after tumour inoculation. Cachexia parameters such as body weight loss, muscle and fat mass, pro-inflammatory cytokine profile, and molecular and morphological aspects of skeletal muscle were also determined. As expected, Walker 256 tumour growth led to muscle function decline, cachexia manifestation symptoms, muscle fibre cross-section area reduction, and classical muscle protein degradation pathway activation, with upregulation of FoxO1, MuRF-1, and 20S proteins. On the other hand, despite having no effect on the walking test, inflammation status or muscle oxidative capacity, the leucine-rich diet improved muscle strength and behaviour performance, maintained body weight, fat and muscle mass and decreased some protein degradation markers in Walker 256 tumour-bearing rats. Indeed, a leucine-rich diet alone could not completely revert cachexia but could potentially diminish muscle protein degradation, leading to better muscle functional performance in cancer cachexia.

Redox regulation by carotenoids: Evidence and conflicts for their application in cancer.

Carotenoids have been constantly investigated since the early fifty for their chemical, biochemical and biological properties being presence in foods. Among the more than 1100 carotenoids synthesized by plants and microorganisms, approximately 50 are present in the human diet, and about 20 can be detected in human blood and tissues. Review articles that discuss the anticancer and cancer preventing activity of phytochemicals have often in common the difficulty to find a coherency between the results deriving from experimental studies and the controversial or weak clinical indications arising from epidemiological and interventional studies. In this scenario, the class of carotenoids does not represent an exception. In fact, according with World Cancer Research Fund, strong evidence exists that high-dose supplementation of ß-carotene increases the risk of lung cancer, while for other types of cancer, the protective or harmful effects of food-containing carotenoids or carotenoid supplements have been considered limited, suggestive or unlikely. The analysis of the mechanistic evidence is complicated by the double nature of carotenoids being molecules acting either as antioxidant or pro-oxidant compounds. The present review analyzes the ambiguity and the unexpected results deriving from the epidemiological and interventional studies and discusses how the effects of carotenoids on cancer risk can be explained by understanding their capacity to modulate the cellular antioxidant response, depending on the concentration applied and the cellular metabolism. In the final part, a new global approach is proposed to study the contribution of carotenoids, but also of other phytochemicals, to disease prevention, including cancer.

Targeting Cancer Stem Cells by Dietary Agents: An Important Therapeutic Strategy against Human Malignancies.

As a multifactorial disease, treatment of cancer depends on understanding unique mechanisms involved in its progression. The cancer stem cells (CSCs) are responsible for tumor stemness and by enhancing colony formation, proliferation as well as metastasis, and these cells can also mediate resistance to therapy. Furthermore, the presence of CSCs leads to cancer recurrence and therefore their complete eradication can have immense therapeutic benefits. The present review focuses on targeting CSCs by natural products in cancer therapy. The growth and colony formation capacities of CSCs have been reported can be attenuated by the dietary agents. These compounds can induce apoptosis in CSCs and reduce tumor migration and invasion via EMT inhibition. A variety of molecular pathways including STAT3, Wnt/ß-catenin, Sonic Hedgehog, Gli1 and NF-κB undergo down-regulation by dietary agents in suppressing CSC features. Upon exposure to natural agents, a significant decrease occurs in levels of CSC markers including CD44, CD133, ALDH1, Oct4 and Nanog to impair cancer stemness. Furthermore, CSC suppression by dietary agents can enhance sensitivity of tumors to chemotherapy and radiotherapy. In addition to in vitro studies, as well as experiments on the different preclinical models have shown capacity of natural products in suppressing cancer stemness. Furthermore, use of nanostructures for improving therapeutic impact of dietary agents is recommended to rapidly translate preclinical findings for clinical use.

Perioperative NSAIDs and Long-Term Outcomes After cancer Surgery: a Systematic Review and Meta-analysis.

PURPOSE OF REVIEW: This review investigated the use of perioperative non-steroidal anti-inflammatory drugs (NSAIDs) and long-term outcomes in cancer surgery patients, and whether this is dependent on cancer type, type of NSAID and timing of administration. FINDINGS: Perioperative NSAID use was found to be associated with longer disease-free survival (hazard ration, HR = 0.84 (95% CI, 0.73-0.97)) and overall survival (HR = 0.78 (95% CI, 0.64-0.94)). No difference was found between different types of NSAID for disease-free survival, although in overall survival ketorolac use was significant (HR = 0.63 (95% CI, 0.42-0.95)). Analysis on the timing of NSAID administration found no subgroup to be associated with cancer outcomes. The cancer-type analysis found an association with outcomes in breast and ovarian cancers. However, the level of certainty remains very low, mostly due to the heterogeneity and the retrospective nature of most studies. Perioperative NSAID use may be associated with increased disease-free and overall survival after cancer surgery. This may be dependent on the type of cancer and type of NSAID, and further research is needed to support this. These data may inform future prospective trials, which are needed to determine the clinical impact, as well as optimal NSAID regimen.

[Real-world study in oncological outpatients of an oral supplement enriched with ω-3 fatty acids - effect on quality of life and nutritional parameters]. / Estudio en vida real de un suplemento oral enriquecido con ácidos grasos ω-3 en pacientes ambulatorios oncológicos: efecto sobre la calidad de vida y los parámetros nutricionales.

INTRODUCTION: Background: cancer patients are a group at high nutritional risk. Oral nutritional supplementation (ONS) can improve nutritional status. Objective: the objective of our study was to evaluate the effectiveness on nutritional parameters and quality of life of a ω3-enriched ONS in oncology outpatients in a real-world study. Material and methods: a total of 35 outpatient cancer patients who received 2 ONS per day were recruited. Chemistry, anthropometric, impedance measurement, nutritional survey, malnutrition universal screening tool (MUST) test, and EQ5D quality of life test were all used before and after 3 months of intervention. Results: mean age was 65.4 ± 10.7 years (18 females/17 males). Mean completion of the group was 81.7 ± 7.2 %. During the intervention, total protein (1.5 ± 0.2 g/dL; p = 0.01), albumin (0.9 ± 0.1 mg/dL; p = 0.04), and transferrin (53.9 ± 21.1 mg/dL; p = 0.02) levels increased. At the beginning of the study, 100 % of the patients were in the high nutritional risk category according to MUST. After the intervention, 34.3 % (n = 12) were in the low nutritional risk category, 51.4 % (n = 18) in the moderate nutritional risk category, and only 14.3 % (n = 5) in the category of high nutritional risk; previously, 100 % of patients had high nutritional risk (p = 0.02). The total score in the quality of life test increased significantly (0.51 ± 0.06 vs 0.84 ± 0.03 points; p = 0.01), with improvement in 5 dimensions. Conclusions: the use of a ω3-enriched ONS in a real-world study with cancer outpatients showed a beneficial effect on nutritional parameters and quality of life.

INTRODUCCIÓN: Antecedentes: los pacientes oncológicos son un grupo de alto riesgo nutricional. Los suplementos orales nutricionales (SON) pueden ayudar a mejorar su situación nutricional. Objetivo: el objetivo de nuestro estudio fue evaluar en un estudio en vida real la efectividad sobre los parámetros nutricionales y la calidad de vida de un SON enriquecido con ω-3 en pacientes ambulatorios oncológicos. Material y métodos: se reclutaron 35 pacientes oncológicos ambulatorios que recibieron 2 SON al día. Se realizaron: valoración bioquímica y antropométrica, impedanciometría, encuesta nutricional, test Malnutrition Universal Screening Tool (MUST) y test de calidad de vida EQ5D, antes y a los 3 meses de intervención. Resultados: la edad media fue de 65,4 ± 10,7 años (18 mujeres/17 hombres). La cumplimentación media del grupo fue de un 81,7 ± 7,2 %. Durante la intervención aumentaron los niveles de proteínas totales (1,5 ± 0,2 g/dl; p = 0,01), albúmina (0,9 ± 0,1 mg/dl; p = 0,04) y transferrina (53,9 ± 21,1 mg/dl; p = 0,02). Al inicio del estudio, un 100 % de los pacientes presentaban en el test MUST la categoría de alto riesgo nutricional. Tras la intervención, un 34,3 % (n = 12) presentaban la categoría de bajo riesgo nutricional, un 51,4 % (n = 18) presentaban en el test MUST la categoría de moderado riesgo nutricional, y solo un 14,3 % (n = 5) presentaban la categoría de alto riesgo nutricional; previamente, el 100 % de los pacientes tenían la categoría alto riesgo (p = 0,02). La puntuación total del test de calidad de vida aumentó significativamente (0,51 ± 0,06 vs. 0,84 ± 0,03 puntos; p = 0,01), mejorando cualitativamente las 5 dimensiones. Conclusiones: la utilización de un SON enriquecido con ω-3 en pacientes oncológicos ambulatorios en condiciones de vida real muestra un efecto beneficioso sobre los parámetros nutricionales y la calidad de vida.

Ketogenic Diet for Cancer: Critical Assessment and Research Recommendations.

Despite remarkable improvements in screening, diagnosis, and targeted therapies, cancer remains the second leading cause of death in the United States. It is increasingly clear that diet and lifestyle practices play a substantial role in cancer development and progression. As such, various dietary compositions have been proposed for reducing cancer risk and as potential adjuvant therapies. In this article, we critically assess the preclinical and human trials on the effects of the ketogenic diet (KD, i.e., high-fat, moderate-to-low protein, and very-low carbohydrate content) for cancer-related outcomes. The mechanisms underlying the hypothesized effects of KD, most notably the Warburg Effect, suggest that restricting carbohydrate content may impede cancer development and progression via several pathways (e.g., tumor metabolism, gene expression). Overall, although preclinical studies suggest that KD has antitumor effects, prolongs survival, and prevents cancer development, human clinical trials are equivocal. Because of the lack of high-quality clinical trials, the effects of KD on cancer and as an adjunctive therapy are essentially unknown. We propose a set of research recommendations for clinical studies examining the effects of KD on cancer development and progression.

Nutraceuticals and their role in tumor angiogenesis.

Angiogenesis plays a pivotal role in cancer initiation, maintenance, and progression. Diet may inhibit, retard or reverse these processes affecting angiogenesis (angioprevention). Nutraceuticals, such as omega-3 fatty acids, amino acids, proteins, vitamins, minerals, fibers, and phenolic compounds, improve health benefits as they are a source of bioactive compounds that, among other effects, can regulate angiogenesis. The literature concerning the pro-angiogenic and/or anti-angiogenic nutraceuticals and the possible activated pathways in cancer and other non-neoplastic diseases by in vivo and in vitro experiments are reviewed.

The impact of physiological metabolite levels on serine uptake, synthesis and utilization in cancer cells.

Serine is a non-essential amino acid that is critical for tumour proliferation and depletion of circulating serine results in reduced tumour growth and increased survival in various cancer models. While many cancer cells cultured in a standard tissue culture medium depend on exogenous serine for optimal growth, here we report that these cells are less sensitive to serine/glycine depletion in medium containing physiological levels of metabolites. The lower requirement for exogenous serine under these culture conditions reflects both increased de novo serine synthesis and the use of hypoxanthine (not present in the standard medium) to support purine synthesis. Limiting serine availability leads to increased uptake of extracellular hypoxanthine, sparing available serine for other pathways such as glutathione synthesis. Taken together these results improve our understanding of serine metabolism in physiologically relevant nutrient conditions and allow us to predict interventions that may enhance the therapeutic response to dietary serine/glycine limitation.