Cyclic fasting-mimicking diet in cancer treatment: Preclinical and clinical evidence

Nutritional strategies in oncology: The role of dietary patterns in modulating tumor progression and treatment response

Dietary interventions can influence tumor growth by restricting tumor-specific nutritional requirements, altering the nutrient availability in the tumor microenvironment, or enhancing the cytotoxicity of anticancer drugs. Metabolic reprogramming of tumor cells, as a significant hallmark of tumor progression, has a profound impact on immune regulation, severely hindering tumor eradication. Dietary interventions can modify tumor metabolic processes to some extent, thereby further improving the efficacy of tumor treatment. In this review, we emphasize the impact of dietary patterns on tumor progression. By exploring the metabolic differences of nutrients in normal cells versus cancer cells, we further clarify how dietary patterns influence cancer treatment. We also discuss the effects of dietary patterns on traditional treatments such as immunotherapy, chemotherapy, radiotherapy, and the gut microbiome, thereby underscoring the importance of precision nutrition.

Transformable albumin-based nanocapsules selectively amplify tumor starvation and disulfidptosis through metabolic deception

Starvation-based therapy has emerged as a promising approach for cancer treatment. However, tumors can effectively circumvent nutrient deprivation by enhancing the uptake of alternative nutrients such as albumin to attenuate the efficacy of starvation-inducing drugs. In this study, we aimed to exploit the compensatory ability of tumors for alternative nutrients to improve the selectivity of starvation therapy. Albumin nanocapsules were coupled with glucose oxidase (GOX) and loaded with V9302 to obtain nutrient-mimicking transformable nanocapsules (HGV) that induced glucose and glutamine depletion. The HGV entered tumors efficiently owing to their transformability and induced starvation, which in turn upregulated the albumin uptake of the tumors to further increase the internalization of nanocapsules as a positive feedback loop. This amplified starvation led to a significant accumulation of intracellular disulfides and triggered disulfidptosis in the tumor cells, which not only effectively inhibited the growth of primary tumors but also stimulated antitumor immune responses. Furthermore, the tumor selectivity of HGV reduced the hepatotoxicity of GOX and V9302, making it a potential translational starvation-inducing nanocapsule.

Dietary nutrient intake and cancer presence: evidence from a cross-sectional study

BACKGROUND

While the role of specific nutrients in cancer is established, associations between comprehensive between dietary nutrient intake and cancer presence remain underexplored. This cross-sectional study investigates global dietary nutrient profiles in relation to solid and blood cancers.

METHODS

A total of 42,732 mobile adults from the National Health and Nutrition Examination Survey (NHANES, 2001-2023) were enrolled in this study. The potential associations of dietary intakes of 34 nutrients and 4 common trace components with cancer presence were investigated by weighted logistic regression and restricted cubic spline.

RESULTS

Higher intake of saturated fatty acid (OR = 1.1082, 95% CI: 1.0110-1.2146), β-carotene (OR = 1.0431, 1.0096-1.0777) and vitamin K (OR = 1.0370, 1.0094-1.0654) was positively associated with overall cancer presence, while phosphorus intake (OR = 0.9016, 0.8218-0.9892) showed a protective association. For solid tumors, dietary intakes of saturated fatty acid (OR = 1.1099), α-carotene (OR = 1.0353), β-carotene (OR = 1.0484), and vitamin K (OR = 1.0405) exhibited positive associations. Retinol intake was linked to blood carcinoma (OR = 1.0935, 1.0222-1.1698). Dose-response analyses revealed linear relationships without non-linear thresholds.

CONCLUSION

Specific dietary nutrients, notably saturated fats, carotenoids, and vitamin K, are associated with increased cancer presence, whereas phosphorus intake is associated with the reduced cancer presence. Due to the cross-sectional nature of the study and the measurement of dietary intake after cancer diagnosis, a causal relationship could not be established. These findings underscore the need for longitudinal studies to establish causality and inform dietary interventions in cancer management.

Fasting as Cancer Treatment: Myth or Breakthrough in Oncology

The concept of fasting as a potential cancer treatment has garnered increasing interest, particularly in light of emerging evidence linking dietary interventions to cancer progression and therapy outcomes. This article explores whether fasting, either intermittent or prolonged, can be a viable standalone treatment for cancer or if its therapeutic potential lies in its adjunctive role. Current research suggests that fasting induces a metabolic shift, which may inhibit cancer cell proliferation by depriving them of essential nutrients. Additionally, fasting has been shown to enhance the body's stress resistance, promote autophagy, and possibly make cancer cells more vulnerable to standard treatments such as chemotherapy and radiotherapy. However, the application of fasting as a sole treatment for cancer remains controversial and lacks substantial clinical validation. While animal models and in vitro studies indicate promising results, the translation to human trials is complex, with various types of cancer responding differently to dietary interventions. Moreover, concerns about malnutrition, loss of muscle mass, and the overall health of cancer patients undergoing fasting without supervision must be addressed. The paper critically examines the myth and reality surrounding fasting as a cancer treatment, reviewing key studies and clinical trials to provide a comprehensive understanding of its efficacy and safety. While fasting may hold promise as a supportive therapy, particularly in combination with traditional treatments, there is currently insufficient evidence to support its use as a primary treatment modality. Further research is needed to establish the parameters in which fasting might be beneficial, such as specific cancer types, patient populations, and optimal fasting regimens. Thus, while the idea of fasting as a cancer breakthrough is compelling, it remains a complementary approach rather than a standalone solution in oncology.

Early downmodulation of tumor glycolysis predicts response to fasting-mimicking diet in triple-negative breast cancer patients

In preclinical experiments, cyclic fasting-mimicking diets (FMDs) showed broad anticancer effects in combination with chemotherapy. Among different tumor types, triple-negative breast cancer (TNBC) is exquisitely sensitive to FMD. However, the antitumor activity and efficacy of cyclic FMD in TNBC patients remain unclear. Here, we show that a severely calorie-restricted, triweekly, 5-day FMD regimen results in excellent pathologic complete response (pCR) rates (primary endpoint) and long-term clinical outcomes (secondary endpoints) when combined with preoperative chemotherapy in 30 patients with early-stage TNBC enrolled in the phase 2 trial BREAKFAST. Bulk and single-cell RNA sequencing analysis revealed that highly glycolytic cancer cells, myeloid cells, and pericytes from tumors achieving pCR undergo a significant, early downmodulation of pathways related to glycolysis and pyruvate metabolism. Our findings pave the wave for conducting larger clinical trials to investigate the efficacy of cyclic FMD in early-stage TNBC patients and to validate early changes of intratumor glycolysis as a predictor of clinical benefit from nutrient restriction. This study was registered at Clinicaltrials.gov (NCT04248998).

Dietary Restrictions and Cancer Prevention: State of the Art

Worldwide, almost 10 million cancer deaths occurred in 2022, a number that is expected to rise to 16.3 million by 2040. Primary prevention has long been acknowledged as a crucial approach to reducing cancer incidence. In fact, between 30 and 50 percent of all tumors are known to be preventable by eating a healthy diet, staying active, avoiding alcohol, smoking, and being overweight. Accordingly, many international organizations have created tumor prevention guidelines, which underlie the importance of following a diet that emphasizes eating plant-based foods while minimizing the consumption of red/processed meat, sugars, processed foods, and alcohol. However, further research is needed to define the relationship between the effect of specific diets or nutritional components on cancer prevention. Interestingly, reductions in food intake and dietetic restrictions can extend the lifespan of yeast, nematodes, flies, and rodents. Despite controversial results in humans, those approaches have the potential to ameliorate health via direct and indirect effects on specific signaling pathways involved in cancer onset. Here, we describe the latest knowledge on the cancer-preventive potential of dietary restrictions and the biochemical processes involved. Molecular, preclinical, and clinical studies evaluating the effects of different fasting strategies will also be reviewed.

Current Evidence on the Impact of Diet, Food, and Supplement Intake on Breast Cancer Health Outcomes in Patients Undergoing Endocrine Therapy

BACKGROUND/OBJECTIVES

The most common type of breast cancer (BRC) in women is estrogen/progesterone receptor positive. First-line treatment includes endocrine therapy, either with aromatase inhibitors or tamoxifen to reduce estrogen levels. Among the side effects produced by this treatment, aromatase inhibitor-induced arthralgia is the most common, affecting the patients' overall health and quality of life (QoL). The objectives here were to evaluate interventions examining the impact of modified diets, supplements, and/or some food components on health outcomes in BRC patients undergoing endocrine therapy.

METHODS

The literature search was performed in PubMed, Scopus, and Web of Science from June 2024, as well as manually, through the end of November 2024. The search was limited to studies of women diagnosed with estrogen/progesterone-receptor-positive BRC with selected articles reporting interventions with diet, food, or supplement intake and examining the relevant health outcomes. Studies not focusing on BRC patients undergoing endocrine therapy or not including specific health outcomes were excluded.

RESULTS

The search uncovered 1028 studies; after the removal of duplicates, abstracts, and irrelevant studies, 53 were closely examined, with 26 evaluated and presented here. The outcomes were changes in bone and body composition, cardiovascular disease risks, inflammation, and QoL.

CONCLUSIONS

The examined evidence suggests that adherence to dietary patterns such as the Mediterranean or a low-fat diet, and a higher intake of fruits and vegetables were beneficial for various outcomes. Additionally, supplementation with some foods/components (dried plum, red clover) contributed to improving/maintaining bone and body composition, especially in overweight/obese patients. Supplementation with vitamin D or omega-3 improved lipid and angiogenic parameters and QoL. Although these results are promising, the effects of each supplement/food cannot be summarized due to the diverse nature of study designs, patients, and supplement dosages. Further studies are needed to explore the effects of specific nutritional interventions (including the newest, like fasting-mimicking diets and whole-grain cereal diets) on various health outcomes in BRC survivors during endocrine therapy, and to derive universal recommendations.

Fasting-mimicking diet potentiates anti-tumor effects of CDK4/6 inhibitors against breast cancer by suppressing NRAS- and IGF1-mediated mTORC1 signaling

Fasting-mimicking diet (FMD) cycles, defined as 3-5 day periods of a calorie-restricted, low-protein, low-carbohydrate, and high-fat diet, have emerged as a dietary approach to delay cancer initiation and progression in both autograft and xenograft mouse models and as a safe and feasible approach to decrease risk factors for cancer and other age-related pathologies in humans. A substantial number of pre-clinical studies focused on various tumor types have shown that fasting/FMDs can potentiate the efficacy of various standard-of-care cancer therapies but also modulate the immune system to promote a T cell-dependent attack of tumor cells. Importantly, combining drug treatment with fasting/FMDs can overcome acquired drug resistance which frequently emerges and reduces long-term treatment benefits. However, the mechanisms by which the FMD reverts resistance to CDK4/6i remain poorly understood. Here, Li and colleagues provide evidence that FMD cycles act as a wild card to reduce the activity of a signaling network that includes IGF-1, RAS, AKT, and mTOR-S6K to delay cancer progression and reverse the acquisition of drug resistance. These findings expand the mechanistic understanding of the FMD-mediated increase in drug efficacy and provide further evidence to support trials combining hormone therapy, CDK4/6 inhibitors, and FMD in breast cancer treatment. These new results on FMD cycles add an optimistic outlook to extend the efficacy of standard-of-care drugs that eventually become ineffective because of acquired resistance.

Systemic and transcriptional response to intermittent fasting and fasting-mimicking diet in mice

BACKGROUND

Dietary restriction (DR) has multiple beneficial effects on health and longevity and can also improve the efficacy of certain therapies. Diets used to instigate DR are diverse and the corresponding response is not uniformly measured. We compared the systemic and liver-specific transcriptional response to intermittent fasting (IF) and commercially available fasting-mimicking diet (FMD) after short- and long-term use in C57BL/6 J mice.

RESULTS

We show that neither DR regimen causes observable adverse effects in mice. The weight loss was limited to 20% and was quickly compensated during refeeding days. The slightly higher weight loss upon FMD versus IF correlated with stronger fasting response assessed by lower glucose levels and higher ketone body, free fatty acids and especially FGF21 concentrations in blood. RNA sequencing demonstrated similar transcriptional programs in the liver after both regimens, with PPARα signalling as top enriched pathway, while on individual gene level FMD more potently increased gluconeogenesis-related, and PPARα and p53 target gene expression compared to IF. Repeated IF induced similar transcriptional responses as acute IF. However, repeated cycles of FMD resulted in blunted expression of genes involved in ketogenesis and fatty acid oxidation.

CONCLUSIONS

Short-term FMD causes more pronounced changes in blood parameters and slightly higher weight loss than IF, while both activate similar pathways (particularly PPARα signalling) in the liver. On individual gene level FMD induces a stronger transcriptional response, whereas cyclic application blunts transcriptional upregulation of fatty acid oxidation and ketogenesis only in FMD. Hence, our comparative characterization of IF and FMD protocols renders both as effective DR regimens and serves as resource in the fasting research field.