Fasting and cancer: molecular mechanisms and clinical application

Exercise, Diet and Sleeping as Regenerative Medicine Adjuvants: Obesity and Ageing as Illustrations

Regenerative medicine uses the biological and medical knowledge on how the cells and tissue regenerate and evolve in order to develop novel therapies. Health conditions such as ageing, obesity and cancer lead to an impaired regeneration ability. Exercise, diet choices and sleeping pattern have significant impacts on regeneration biology via diverse pathways including reducing the inflammatory and oxidative components. Thus, exercise, diet and sleeping management can be optimized towards therapeutic applications in regenerative medicine. It could allow to prevent degeneration, optimize the biological regeneration and also provide adjuvants for regenerative medicine.

Short-term starvation synergistically enhances cytotoxicity of Niraparib via Akt/mTOR signaling pathway in ovarian cancer therapy

Background

Short-term starvation (STS) has gradually been confirmed as a treatment method that synergistically enhances the effect of chemotherapy on malignant tumours. In clinical applications, there are still some limitations of poly (ADP-ribose) polymerase inhibitors (PARPi), including understanding their effectiveness and side effects. Here, we sought to investigate the effect and mechanism of the combined use of STS and niraparib in the treatment of ovarian cancer.

Methods

In in vitro experiments, SKOV3 and A2780 ovarian cancer cells were treated with STS and niraparib alone or in combination. Cell viability was assessed with CCK-8, and cell cycle, apoptosis, DNA damage repair and autophagy were examined to explore the molecular mechanisms. Akt and mTOR inhibitors were used to examine any changes in DNA damage repair levels. Xenograft animal models were treated with STS and niraparib, and HE staining and immunohistochemistry were performed to examine the effects.

Results

The combined use of STS and niraparib inhibited cell proliferation and increased apoptosis more than niraparib application alone. In addition, compared with the niraparib group, the STS + niraparib group had increased G2/M arrest, DNA damage and autophagy, which indicated that STS pretreatment enhanced the cytotoxicity of niraparib. In animal experiments, STS did not affect the growth of transplanted tumours, but the combined treatment synergistically enhanced the cytotoxicity of niraparib. In in vivo experiments, STS did not affect the growth of transplanted tumours, but the combined treatment synergistically enhanced the cytotoxicity of niraparib and reduced the small intestinal side effects caused by niraparib chemotherapy.

Conclusion

STS pretreatment can synergistically enhance the cytotoxicity of niraparib. STS + niraparib is a potentially effective strategy in the maintenance therapy of ovarian cancer.

Distinct Metabolism of Bone Marrow Adipocytes and their Role in Bone Metastasis

Bone marrow adipocytes (BMAs) represent 10% of the total fat mass of the human body and serve as an energy reservoir for the skeletal niche. They function as an endocrine organ by actively secreting fatty acids, cytokines, and adipokines. The volume of BMAs increases along with age, osteoporosis and/or obesity. With the rapid development of multi-omic analysis and the advance in in vivo imaging technology, further distinct characteristics and functions of BMAs have been revealed. There is accumulating evidence that BMAs are metabolically, biologically and functionally unique from white, brown, beige and pink adipocytes. Bone metastatic disease is an uncurable complication in cancer patients, where primary cancer cells spread from their original site into the bone marrow. Recent publications have highlighted those BMAs could also serve as a rich lipid source of fatty acids that can be utilized by the cancer cells during bone metastasis, particularly for breast, prostate, lung, ovarian and pancreatic cancer as well as melanoma. In this review, we summarize the novel progressions in BMAs metabolism, especially with multi-omic analysis and in vivo imaging technology. We also update the metabolic role of BMAs in bone metastasis, and their potential new avenues for diagnosis and therapies against metastatic cancers.

Do Cancer and Cancer Treatments Accelerate Aging?

PURPOSE OF REVIEW

This review focuses on describing the mechanisms and clinical manifestations that underlie accelerated aging associated with cancer and its treatment.

RECENT FINDINGS

The direct and indirect effects of cancer and its treatment are associated with late occurrence of comorbidities that happen earlier or more frequently in cancer survivors compared to cancer-free individuals, otherwise known as accelerated aging. Use of senolytics and dietary and exercise interventions including prehabilitation, caloric restriction, and rehabilitation are currently under investigation to reverse or decelerate the aging process and will be covered in this review. Further research on how to decelerate or reverse aging changes associated with cancer and its treatment will be of paramount importance as the number of cancer survivors continues to grow.

Effects of Fasting on Chemotherapy Treatment Response: A Systematic Review of Current Evidence and Suggestions for the Design of Future Clinical Trials

Fasting associated with chemotherapy could improve the efficacy of anticancer treatments without increasing their adverse effects. We conducted a systematic review following the PRISMA Statement to summarize the evidence on the effects of fasting on treatment response of adults undergoing chemotherapy and make suggestions for the design of future clinical trials The search was performed on CENTRAL, PubMed/MEDLINE, LILACS and Embase. Randomized and non-randomized clinical trials evaluating the effects of fasting (above 12 h, at anytime) on treatment response of adult cancer patients undergoing chemotherapy were included. The risk of bias assessment was conducted in accordance with the Cochrane Handbook. Literature search retrieved 1393 citations and three studies were included in the review. All studies had as an intervention fasting of at least 24 h, before chemotherapy. Two studies showed that immediately after chemotherapy, damage to healthy cells was increased, however after 48 and 72 h, of fasting there was a decrease on damage magnitude. There was no difference in chemotherapy-related adverse events between intervention and control groups. All studies presented two or more criteria with a high risk of bias. Fasting of at least 24 h, appears to be safe and showed some beneficial effects on chemotherapy toxicity, that could be further investigated, however studies presented heterogeneous samples and protocols. We highlight the need and provide recommendations for well-designed randomized clinical trials that evaluate the effect of fasting on chemotherapy-related adverse events. This systematic review was registered on PROSPERO as CRD42019120071.

Mitigation of Iron Irradiation-Induced Genotoxicity and Genomic Instability by Postexposure Dietary Restriction in Mice

Background and Purpose. Postexposure onset of dietary restriction (DR) is expected to provide therapeutic nutritional approaches to reduce health risk from exposure to ionizing radiation (IR) due to such as manned space exploration, radiotherapy, or nuclear accidents as IR could alleviate radiocarcinogenesis in animal models. However, the underlying mechanisms remain largely unknown. This study is aimed at investigating the effect from postexposure onset of DR on genotoxicity and genomic instability (GI) induced by total body irradiation (TBI) in mice. Materials and Methods. Mice were exposed to 2.0 Gy of accelerated iron particles with an initial energy of 500 MeV/nucleon and a linear energy transfer (LET) value of about 200 keV/μm. After TBI, mice were either allowed to free access to a standard laboratory chow or treated under DR (25% cut in diet). Using micronucleus frequency (MNF) in bone marrow erythrocytes, induction of acute genotoxicity and GI in the hematopoietic system was, respectively, determined 1 and 2 months after TBI. Results and Conclusions. TBI alone caused a significant increase in MNF while DR alone did not markedly influence the MNF. DR induced a significant decrease in MNF compared to the treatment by TBI alone. Results demonstrated that postexposure onset of DR could relieve the elevated MNF induced by TBI with high-LET iron particles. These findings indicated that reduction in acute genotoxicity and late GI may be at least a part of the mechanisms underlying decreased radiocarcinogenesis by DR.

Intermittent Fasting before Laparotomy: Effects on Glucose Control and Histopathologic Findings in Diabetic Rats

(1) Background: Intermittent fasting is a nutrition practice in which individuals fast for several hours in a day, mainly with feeding time during the daylight hours. They seek to improve metabolic performance and cellular resistance to stress. In this study, we tested the fasting protocol to investigate the glycemic effect in a laparotomy perioperative period in diabetic rats and histopathologic findings. (2) Methods: The animals were diabetic-induced with alloxan. Two groups were set according to the feeding protocol: free food and intermittent fasting, whose rats could only eat 8 h in the daylight. Both groups were anesthetized, and a laparotomy was performed. We evaluated the glucose levels during the perioperative period, and we accessed organ histology seeking damage of kidney, bowel and liver after surgical trauma, and we evaluated the wound healing process. (3) Results: Glycemic levels were improved in the intermittent fasting group, especially in the post-operative period after laparotomy. Comparing both groups' tubular damage showed interdependency with mice with worse glycemic level (Z = 2.3; p = 0.0215) and wound-healing parameters showed interdependency with rats with better glycemic status for neovascularization (Z = 2.2; p = 0.0273) and the presence of sebaceous and sweat gland in the healing process (Z = 2.30; p = 0.0215). (4) Conclusions: Intermittent fasting before surgery can be a tool to improve glycemic levels in diabetic rats, with improvement especially in the post-operative period.

Randomised controlled trial of intermittent vs continuous energy restriction during chemotherapy for early breast cancer

BACKGROUND

Excess adiposity at diagnosis and weight gain during chemotherapy is associated with tumour recurrence and chemotherapy toxicity. We assessed the efficacy of intermittent energy restriction (IER) vs continuous energy restriction (CER) for weight control and toxicity reduction during chemotherapy.

METHODS

One hundred and seventy-two women were randomised to follow IER or CER throughout adjuvant/neoadjuvant chemotherapy. Primary endpoints were weight and body fat change. Secondary endpoints included chemotherapy toxicity, cardiovascular risk markers, and correlative markers of metabolism, inflammation and oxidative stress.

RESULTS

Primary analyses showed non-significant reductions in weight (-1.1 (-2.4 to +0.2) kg, p = 0.11) and body fat (-1.0 (-2.1 to +0.1) kg, p = 0.086) in IER compared with CER. Predefined secondary analyses adjusted for body water showed significantly greater reductions in weight (-1.4 (-2.5 to -0.2) kg, p = 0.024) and body fat (-1.1 (-2.1 to -0.2) kg, p = 0.046) in IER compared with CER. Incidence of grade 3/4 toxicities were comparable overall (IER 31.0 vs CER 36.5%, p = 0.45) with a trend to fewer grade 3/4 toxicities with IER (18%) vs CER (31%) during cycles 4-6 of primarily taxane therapy (p = 0.063).

CONCLUSIONS

IER is feasible during chemotherapy. The potential efficacy for weight control and reducing toxicity needs to be tested in future larger trials.

CLINICAL TRIAL REGISTRATION

ISRCTN04156504.

Time-restricted feeding induces Lactobacillus- and Akkermansia-specific functional changes in the rat fecal microbiota

Diet is a key factor influencing gut microbiota (GM) composition and functions, which in turn affect host health. Among dietary regimens, time-restricted (TR) feeding has been associated to numerous health benefits. The impact of TR feeding on the GM composition has been mostly explored by means of metagenomic sequencing. To date, however, little is known about the modulation of GM functions by this dietary regimen. Here, we analyzed the effects of TR feeding on GM functions by evaluating protein expression changes in a rat model through a metaproteomic approach. We observed that TR feeding has a relevant impact on GM functions, specifically leading to an increased abundance of several enzymes involved in carbohydrate and protein metabolism and expressed by Lactobacillus spp. and Akkermansia muciniphila. Taken together, these results contribute to deepening our knowledge about the key relationship between diet, GM, and health.

Combined Therapy with microRNA-Expressing Salmonella and Irradiation in Melanoma

Anticancer treatment strategies using bacteria as a vector are currently expanding with the development of anticancer drugs. Here, we present a research strategy to develop anticancer drugs using bacteria that contain miRNAs. We also present a strategy for the development of novel bacterial anticancer drugs in combination with radiation. Salmonella strains expressing miRNA were produced by modifying the miRNA expression vector encoding INHA, a radiation-resistant gene developed previously. The anticancer effect of INHA was confirmed using skin cancer cell lines. We also tested a combination strategy comprising bacteria and radiation for its anticancer efficacy against radiation-resistant mouse melanoma to increase the efficacy of radiation therapy as a novel strategy. The recombinant strain was confirmed to promote effective cell death even when combined with radiation therapy, which exerts its cytotoxicity by enhancing reactive oxygen species production. Moreover, a combination of bacterial and radiation therapy enhanced radiotherapy efficacy. When combined with radiation therapy, bacterial therapy exhibited effective anti-cancer properties even when administered to animals harboring radiation-resistant tumors. This strategy may promote the secretion of cytokines in cells and more effectively reduce the number of bacteria remaining in the animal. Thus, this study may lead to the development of a strategy to improve the effectiveness of radiation therapy using Salmonella expressing cancer-specific miRNA for intractable cancers such as those resistant to radiation.

Diet composition influences the metabolic benefits of short cycles of very low caloric intake

Diet composition, calories, and fasting times contribute to the maintenance of health. However, the impact of very low-calorie intake (VLCI) achieved with either standard laboratory chow (SD) or a plant-based fasting mimicking diet (FMD) is not fully understood. Here, using middle-aged male mice we show that 5 months of short 4:10 VLCI cycles lead to decreases in both fat and lean mass, accompanied by improved physical performance and glucoregulation, and greater metabolic flexibility independent of diet composition. A long-lasting metabolomic reprograming in serum and liver is observed in mice on VLCI cycles with SD, but not FMD. Further, when challenged with an obesogenic diet, cycles of VLCI do not prevent diet-induced obesity nor do they elicit a long-lasting metabolic memory, despite achieving modest metabolic flexibility. Our results highlight the importance of diet composition in mediating the metabolic benefits of short cycles of VLCI.

Transcriptomic Analysis of Laying Hens Revealed the Role of Aging-Related Genes during Forced Molting

Molting in birds provides us with an ideal genetic model for understanding aging and rejuvenation since birds present younger characteristics for reproduction and appearance after molting. Forced molting (FM) by fasting in chickens causes aging of their reproductive system and then promotes cell redevelopment by providing water and feed again. To reveal the genetic mechanism of rejuvenation, we detected blood hormone indexes and gene expression levels in the hypothalamus and ovary of hens from five different periods during FM. Three hormones were identified as participating in FM. Furthermore, the variation trends of gene expression levels in the hypothalamus and ovary at five different stages were found to be basically similar using transcriptome analysis. Among them, 45 genes were found to regulate cell aging during fasting stress and 12 genes were found to promote cell development during the recovery period in the hypothalamus. In addition, five hub genes (INO80D, HELZ, AGO4, ROCK2, and RFX7) were identified by WGCNA. FM can restart the reproductive function of aged hens by regulating expression levels of genes associated with aging and development. Our study not only enriches the theoretical basis of FM but also provides insights for the study of antiaging in humans and the conception mechanism in elderly women.

Innate immune remodeling by short-term intensive fasting

Previous studies have shown that long-term light or moderate fasting such as intermittent fasting can improve health and prolong lifespan. However, in humans short-term intensive fasting, a complete water-only fasting has little been studied. Here, we used multi-omics tools to evaluate the impact of short-term intensive fasting on immune function by comparison of the CD45+ leukocytes from the fasting subjects before and after 72-h fasting. Transcriptomic and proteomic profiling of CD45+ leukocytes revealed extensive expression changes, marked by higher gene upregulation than downregulation after fasting. Functional enrichment of differentially expressed genes and proteins exposed several pathways critical to metabolic and immune cell functions. Specifically, short-term intensive fasting enhanced autophagy levels through upregulation of key members involved in the upstream signals and within the autophagy machinery, whereas apoptosis was reduced by down-turning of apoptotic gene expression, thereby increasing the leukocyte viability. When focusing on specific leukocyte populations, peripheral neutrophils are noticeably increased by short-term intensive fasting. Finally, proteomic analysis of leukocytes showed that short-term intensive fasting not only increased neutrophil degranulation, but also increased cytokine secretion. Our results suggest that short-term intensive fasting boost immune function, in particular innate immune function, at least in part by remodeling leukocytes expression profile.

Intermittent fasting in the prevention and treatment of cancer

Chronic caloric restriction (CR) has powerful anticarcinogenic actions in both preclinical and clinical studies but may be difficult to sustain. As an alternative to CR, there has been growing interest in intermittent fasting (IF) in both the scientific and lay community as a result of promising study results, mainly in experimental animal models. According to a survey by the International Food Information Council Foundation, IF has become the most popular diet in the last year, and patients with cancer are seeking advice from oncologists about its beneficial effects for cancer prevention and treatment. However, as discussed in this review, results from IF studies in rodents are controversial and suggest potential detrimental effects in certain oncologic conditions. The effects of IF on human cancer incidence and prognosis remain unknown because of a lack of high-quality randomized clinical trials. Preliminary studies suggest that prolonged fasting in some patients who have cancer is safe and potentially capable of decreasing chemotherapy-related toxicity and tumor growth. However, because additional trials are needed to elucidate the risks and benefits of fasting for patients with cancer, the authors would not currently recommend patients undergoing active cancer treatment partake in IF outside the context of a clinical trial. IF may be considered in adults seeking cancer-prevention benefits through means of weight management, but whether IF itself affects cancer-related metabolic and molecular pathways remains unanswered.

Low glycaemic diets alter lipid metabolism to influence tumour growth

Dietary interventions can change metabolite levels in the tumour microenvironment, which might then affect cancer cell metabolism to alter tumour growth1-5. Although caloric restriction (CR) and a ketogenic diet (KD) are often thought to limit tumour progression by lowering blood glucose and insulin levels6-8, we found that only CR inhibits the growth of select tumour allografts in mice, suggesting that other mechanisms contribute to tumour growth inhibition. A change in nutrient availability observed with CR, but not with KD, is lower lipid levels in the plasma and tumours. Upregulation of stearoyl-CoA desaturase (SCD), which synthesises monounsaturated fatty acids, is required for cancer cells to proliferate in a lipid-depleted environment, and CR also impairs tumour SCD activity to cause an imbalance between unsaturated and saturated fatty acids to slow tumour growth. Enforcing cancer cell SCD expression or raising circulating lipid levels through a higher-fat CR diet confers resistance to the effects of CR. By contrast, although KD also impairs tumour SCD activity, KD-driven increases in lipid availability maintain the unsaturated to saturated fatty acid ratios in tumours, and changing the KD fat composition to increase tumour saturated fatty acid levels cooperates with decreased tumour SCD activity to slow tumour growth. These data suggest that diet-induced mismatches between tumour fatty acid desaturation activity and the availability of specific fatty acid species determine whether low glycaemic diets impair tumour growth.

Does daily fasting shielding kidney on hyperglycemia-related inflammatory cytokine via TNF-α, NLRP3, TGF-β1 and VCAM-1 mRNA expression

This study aimed to investigate the effects of blood glucose control and the kidneys' functions, depending on fasting, in the streptozotocin-induced diabetes model in rats via TNF-α, NLRP-3, TGF-β1 and VCAM-1 mRNA expression in the present study. 32 Wistar albino rats were allocated randomly into four main groups; H (Healthy, n = 6), HF (Healthy fasting, n = 6), D (Diabetes, n = 10), DF (Diabetes and fasting, n = 10). Blood glucose and HbA1c levels significantly increased in the D group compared to the healthy ones (p < 0.05). However, the fasting period significantly improved blood glucose and HbA1c levels 14 days after STZ induced diabetes in rats compared to the D group. Similar findings we obtained for serum (BUN-creatinine) and urine samples (creatinine and urea levels). STZ induced high glucose levels significantly up-regulated TNF-α, NLRP-3, TGF-β1 and VCAM-1 mRNA expression and fasting significantly decreased these parameters when compared to diabetic rats. Histopathological staining also demonstrated the protective effects of fasting on diabetic kidney tissue. In conclusion, intermittent fasting regulated blood glucose level as well as decreasing harmful effects of diabetes on kidney tissue. The fasting period significantly decreased the hyperglycemia-related inflammatory cytokine damage on kidneys and also reduced apoptosis in favor of living organisms.

Avenues of research in dietary interventions to target tumor metabolism in osteosarcoma

Osteosarcoma (OS) is the most frequent primary bone cancer, affecting mostly children and adolescents. Although much progress has been made throughout the years towards treating primary OS, the 5-year survival rate for metastatic OS has remained at only 20% for the last 30 years. Therefore, more efficient treatments are needed. Recent studies have shown that tumor metabolism displays a unique behavior, and plays important roles in tumor growth and metastasis, making it an attractive potential target for novel therapies. While normal cells typically fuel the oxidative phosphorylation (OXPHOS) pathway with the products of glycolysis, cancer cells acquire a plastic metabolism, uncoupling these two pathways. This allows them to obtain building blocks for proliferation from glycolytic intermediates and ATP from OXPHOS. One way to target the metabolism of cancer cells is through dietary interventions. However, while some diets have shown anticancer effects against certain tumor types in preclinical studies, as of yet none have been tested to treat OS. Here we review the features of tumor metabolism, in general and about OS, and propose avenues of research in dietary intervention, discussing strategies that could potentially be effective to target OS metabolism.

Daily caloric restriction limits tumor growth more effectively than caloric cycling regardless of dietary composition

Cancer incidence increases with age and is a leading cause of death. Caloric restriction (CR) confers benefits on health and survival and delays cancer. However, due to CR's stringency, dietary alternatives offering the same cancer protection have become increasingly attractive. Short cycles of a plant-based diet designed to mimic fasting (FMD) are protective against tumorigenesis without the chronic restriction of calories. Yet, it is unclear whether the fasting time, level of dietary restriction, or nutrient composition is the primary driver behind cancer protection. Using a breast cancer model in mice, we compare the potency of daily CR to that of periodic caloric cycling on FMD or an isocaloric standard laboratory chow against primary tumor growth and metastatic burden. Here, we report that daily CR provides greater protection against tumor growth and metastasis to the lung, which may be in part due to the unique immune signature observed with daily CR.

Tumor-activatable biomineralized nanotherapeutics for integrative glucose starvation and sensitized metformin therapy

Metformin is a clinically-approved anti-diabetic drug with emerging antitumor potential, but its antitumor activity is highly susceptible to local glucose abundance. Herein, we construct a nanotherapeutic platform based on biocompatible constituents to sensitize tumor cells for metformin therapy via cooperative glucose starvation. The nanoplatform was synthesized through the spontaneous biomineralization of glucose oxidase (GOx) and metformin in amorphous calcium phosphate nanosubstrate, which was further modified with polyethylene glycol and cRGD ligands. This biomineralized nanosystem could efficiently deliver the therapeutic payloads to tumor cells in a targeted and bioresponsive manner. Here GOx could catalyze the oxidation of glucose into gluconic acid and H₂O₂, thus depleting the glucose in tumor intracellular compartment while accelerating the release of the entrapped therapeutic payloads. The selective glucose deprivation would not only disrupt tumor energy metabolism, but also upregulate the PP2A regulatory subunit B56δ and sensitize tumor cells to the metformin-induced CIP2A inhibition, leading to efficient apoptosis induction via PP2A-GSK3β-MCL-1 axis with negligible side effects. This study may offer new avenues for targeted tumor therapy in the clinical context.

Designing Relevant Preclinical Rodent Models for Studying Links Between Nutrition, Obesity, Metabolism, and Cancer

Diet and nutrition are intricately related to cancer prevention, growth, and treatment response. Preclinical rodent models are a cornerstone to biomedical research and remain instrumental in our understanding of the relationship between cancer and diet and in the development of effective therapeutics. However, the success rate of translating promising findings from the bench to the bedside is suboptimal. Well-designed rodent models will be crucial to improving the impact basic science has on clinical treatment options. This review discusses essential experimental factors to consider when designing a preclinical cancer model with an emphasis on incorporatingthese models into studies interrogating diet, nutrition, and metabolism. The aims of this review are to (a) provide insight into relevant considerations when designing cancer models for obesity, nutrition, and metabolism research; (b) identify common pitfalls when selecting a rodent model; and (c) discuss strengths and limitations of available preclinical models.

Using Free-Range Laboratory Mice to Explore Foraging, Lifestyle, and Diet Issues in Cancer

As cancer progresses, its impact should manifest in the foraging behavior of its host much like the effects of endo-parasites that hinder foraging aptitudes and risk management abilities. Furthermore, the lifestyle of the host can impact tumor growth and quality of life. To approach these questions, we conducted novel experiments by letting C57BL/6 laboratory mice, with or without oral squamous cell carcinoma, free range in a large outdoor vivarium. Our goals were to: (1) determine whether one could conduct experiments with a mouse model under free range conditions, (2) measure effects of cancer burden on foraging metrics, (3) compare tumor growth rates with laboratory housed mice, and (4) begin to sort out confounding factors such as diet. With or without cancer, the C57BL/6 laboratory mice dealt with natural climatic conditions and illumination, found shelter or dug burrows, sought out food from experimental food patches, and responded to risk factors associated with microhabitat by foraging more thoroughly in food patches under bush (safe) than in the open (risky). We quantified foraging using giving-up densities of food left behind in the food patches. The mice’s patch use changed over time, and was affected by disease status, sex, and microhabitat. Males, which were larger, consumed more food and had lower giving-up densities than females. Relative to cancer-free mice, mice with growing tumors lost weight, harvested more food, and increasingly relied on patches in the bush microhabitat. The tumors of free-ranging mice in the vivarium grew slower than those of their cohort that were housed in mouse cages in animal facilities. Numerous interesting factors could explain the difference in tumor growth rates: activity levels, stress, weather, food intake, diet, and more. To tease apart one of these intertwined factors, we found that tumors grew faster when mice in the laboratory were fed on millet rather than laboratory mouse chow. While just a start, these novel experiments and framework show how free-ranging mice provide a model that can test a broader range of hypotheses and use a broader range of metrics regarding cancer progression and its consequences for the host.

Intermittent fasting suppressed splenic CD205+ G-MDSC accumulation in a murine breast cancer model by attenuating cell trafficking and inducing apoptosis

Immune-based interventions are the most promising approach for new cancer treatments to achieve long-term cancer-free survival. However, the expansion of myeloid-derived suppression cells (MDSCs) attenuates the therapeutic potential of immunotherapy. We recently showed that CD205+ granulocytic MDSCs (G-MDSCs), but not T cells, are sensitive to glucose deficiency. Intermittent fasting (IF) may inhibit the growth of malignant cells by reducing serum glucose levels, but little is known regarding the influence of IF on MDSC expansion. Herein, we observed that IF selectively inhibited splenic accumulation of CD205+ G-MDSCs in a 4T1 and 4T07 transplant murine breast cancer model. The efficiency of IF in suppressing tumor growth was comparable to that of docetaxel. Further examination revealed that CXCR4 expression was concentrated in CD205+ subsets of tumor-induced G-MDSCs. Downregulation of CXCR4 correlated with a reduction in CD205+ G-MDSC trafficking from bone marrow to the spleen under IF treatment. In addition, ex vivo culture assays showed that glucose deficiency and 2-deoxy-D-glucose (2DG) treatment selectively induced massive death of splenic CD205+ G-MDSCs. Interestingly, 2DG emulated the phenomena of IF selectively suppressing the accumulation of CD205+ G-MDSCs in the spleen, upregulating cleaved caspase 3 in the tumor, downregulating Ki67 in the lung, and retarding the growth of transplanted 4T1 and 4T07 murine breast tumors. These findings suggest that IF inhibited cell trafficking through the downregulation of CXCR4 and induced apoptosis by altering glucose metabolism; this, suppressed the accumulation of tumor-induced splenic CD205+ G-MDSCs and in turn enhanced antitumor immunity.

Metabolic fasting stress is ameliorated in Kinin B1 receptor-deficient mice

The liver has an essential role in responding to metabolic demands under stress conditions. The organ stores, releases, and recycles metabolism-related substrates. However, it is not clear how the Kallikrein-Kinin System modulates metabolic flexibility shift between energetic sources.

AIMS

To analyze the hepatic metabolism in kinin B1 receptor deficient mice (B1KO mice) under fasting conditions.

MAIN METHODS

WT and B1KO male mice were allocated in a calorimetric cage for 7 days and 48 h before the euthanasia, half of the animals of both groups were under fasting conditions. Biochemical parameters, ketone bodies (KB), and gene expression involving the liver energetic metabolism genes were evaluated.

KEY FINDINGS

Kinin B1 receptor (B1R) modulates the metabolic shift under fasting conditions, reducing the VO₂ expenditure. A preference for carbohydrates as an energetic source is suggested, as the B1KO group did not display an increase in KB in the serum. Moreover, the B1KO animals displayed higher serum triglycerides concentration compared to WT fasting mice. Interestingly, the lack of B1R induces the increase expression of enzymes from the glycolysis and lipolysis pathways under the fed. However, under fasting, the enzymatic expression of gluconeogenesis, glyceroneogenesis, and ketogenesis of these pathways does not occur, suggesting an absence of the shift metabolism responsivity, and this condition is modulated by PDK4 under FOXO1 control.

SIGNIFICANCE

B1R has an important role in the hepatic glucose metabolism, which in turn influences the energetic metabolism, and in long-term outcomes, such as in the decrease in hepatic glycogen stores and in the enhancement of hepatic metabolism.

Evaluation of the Effects of Different Dietary Patterns on Breast Cancer: Monitoring Circulating Tumor Cells

The occurrence and development of breast cancer are closely related to dietary factors, especially dietary patterns. This study was to investigate the effects of dietary patterns on the process of tumor metastasis by in vivo circulating tumor cell (CTC) capture strategy and monitoring changes of CTC numbers in breast tumor mice model. Meanwhile, the effects of different dietary patterns on the development of lung metastases of breast cancer and the volume and weight of carcinoma in situ were investigated. In this study, the increase in the number of CTCs was significantly promoted by dietary patterns such as high-salt diet, high-sugar diet, and high-fat diet, while it was delayed by ketogenic diet, low-fat diet, low-protein diet, diet restriction, and Mediterranean diet. These results indicated that the in vivo capture and detection of CTCs provides a convenient method for real-time cancer metastasis monitoring, and through in-depth study of the effects of different dietary patterns on tumor growth and metastasis, it can expand a new horizon in future cancer treatments.

Safety, Feasibility, and Effects of Short-Term Calorie Reduction during Induction Chemotherapy in Patients with Diffuse Large B-Cell Lymphoma: A Pilot Study

Short-term calorie reduction (SCR) requires individuals to reduce their calorie intake to less than 50% of normal requirements and has shown good tolerance and potential benefits in prior studies addressing gynecological cancer patients. More studies are needed to further confirm its safety, feasibility, and effects in patients with different cancers, including hematological malignancies. This pilot cohort study with a matched-pair comparison group was registered at ClinicalTrails.gov [201810112RIND]. Adult patients diagnosed with advanced-stage diffuse large-B cell lymphoma were recruited (SCR group) and matched with one comparison patient (comparison group), each in a manner blinded to their outcomes. The SCR group undertook at least two cycles of 48 h water fast along with their chemotherapy R-CHOP. Descriptive analysis and generalized estimating equations were used to analyze the data. Six participants completed multiple cycles of SCR and were compared to their six counterparts in the comparison group. The results showed that SCR is safe and feasible in terms of a high compliance rate and stable nutritional status. The SCR was associated with benefits in post-chemotherapy hematological parameters (i.e., erythrocyte [p < 0.001] and lymphocyte counts [p < 0.001]). More randomized controlled trials are needed to validate the effects of SCR on different types of cancer populations.

Fucoidan-Supplemented Diet Potentiates Immune Checkpoint Blockage by Enhancing Antitumor Immunity

Immune checkpoint blockade (ICB) therapies such as PD-1 antibodies have produced significant clinical responses in treating a variety of human malignancies, yet only a subset of cancer patients benefit from such therapy. To improve the ICB efficacy, combinations with additional therapeutics were under intensive investigation. Recently, special dietary compositions that can lower the cancer risk or inhibit cancer progression have drawn significant attention, although few were reported to show synergistic effects with ICB therapies. Interestingly, Fucoidan is naturally derived from edible brown algae and exhibits antitumor and immunomodulatory activities. Here we discover that fucoidan-supplemented diet significantly improves the antitumor activities of PD-1 antibodies in vivo. Specifically, fucoidan as a dietary ingredient strongly inhibits tumor growth when co-administrated with PD-1 antibodies, which effects can be further strengthened when fucoidan is applied before PD-1 treatments. Immune analysis revealed that fucoidan consistently promotes the activation of tumor-infiltrating CD8⁺ T cells, which support the evident synergies with ICB therapies. RNAseq analysis suggested that the JAK-STAT pathway is critical for fucoidan to enhance the effector function of CD8⁺ T cells, which could be otherwise attenuated by disruption of the T-cell receptor (TCR)/CD3 complex on the cell surface. Mechanistically, fucoidan interacts with this complex and augments TCR-mediated signaling that cooperate with the JAK-STAT pathway to stimulate T cell activation. Taken together, we demonstrated that fucoidan is a promising dietary supplement combined with ICB therapies to treat malignancies, and dissected an underappreciated mechanism for fucoidan-elicited immunomodulatory effects in cancer.

Combined intermittent fasting and ERK inhibition enhance the anti-tumor effects of chemotherapy via the GSK3β-SIRT7 axis

Dietary interventions such as intermittent fasting (IF) have emerged as an attractive strategy for cancer therapies; therefore, understanding the underlying molecular mechanisms is pivotal. Here, we find SIRT7 decline markedly attenuates the anti-tumor effect of IF. Mechanistically, AMP-activated protein kinase (AMPK) phosphorylating SIRT7 at T263 triggers further phosphorylation at T255/S259 by glycogen synthase kinase 3β (GSK3β), which stabilizes SIRT7 by decoupling E3 ligase UBR5. SIRT7 hyperphosphorylation achieves anti-tumor activity by disrupting the SKP2-SCF E3 ligase, thus preventing SKP2-mediated K63-linked AKT polyubiquitination and subsequent activation. In contrast, GSK3β-SIRT7 axis is inhibited by EGF/ERK2 signaling, with ERK2 inactivating GSK3β, thus accelerating SIRT7 degradation. Unfavorably, glucose deprivation or chemotherapy hijacks the GSK3β-SIRT7 axis via ERK2, thus activating AKT and ensuring survival. Notably, Trametinib, an FDA-approved MEK inhibitor, enhances the efficacy of combination therapy with doxorubicin and IF. Overall, we have revealed the GSK3β-SIRT7 axis that must be fine-tuned in the face of the energetic and oncogenic stresses in malignancy.

The combination of intermittent fasting and chemotherapy can improve the response to treatment. Here, the authors show that SIRT7 activation is required to inactivate Akt during intermittent fasting and that the combination of intermittent fasting and inhibitors that block the Erk pathway can improve efficacy of treatment.

Safety and Feasibility of Fasting-Mimicking Diet and Effects on Nutritional Status and Circulating Metabolic and Inflammatory Factors in Cancer Patients Undergoing Active Treatment

In preclinical studies, fasting was found to potentiate the effects of several anticancer treatments, and early clinical studies indicated that patients may benefit from regimes of modified fasting. However, concerns remain over possible negative impact on the patients' nutritional status. We assessed the feasibility and safety of a 5-day "Fasting-Mimicking Diet" (FMD) as well as its effects on body composition and circulating growth factors, adipokines and cyto/chemokines in cancer patients. In this single-arm, phase I/II clinical trial, patients with solid or hematologic malignancy, low nutritional risk and undergoing active medical treatment received periodic FMD cycles. The body weight, handgrip strength and body composition were monitored throughout the study. Growth factors, adipokines and cyto/chemokines were assessed by ELISA. Ninety patients were enrolled, and FMD was administered every three weeks/once a month with an average of 6.3 FMD cycles/patient. FMD was largely safe with only mild side effects. The patients' weight and handgrip remained stable, the phase angle and fat-free mass increased, while the fat mass decreased. FMD reduced the serum c-peptide, IGF1, IGFBP3 and leptin levels, while increasing IGFBP1, and these modifications persisted for weeks beyond the FMD period. Thus, periodic FMD cycles are feasible and can be safely combined with standard antineoplastic treatments in cancer patients at low nutritional risk. The FMD resulted in reduced fat mass, insulin production and circulating IGF1 and leptin. This trial was registered on Clinicaltrials.gov in July 2018 with the identifier NCT03595540.

The effect of caloric restriction and fasting on cancer

Cancer is one of the most frequent causes of worldwide death and morbidity and is a major public health problem. Although, there are several widely used treatment methods including chemo-, immune- and radiotherapies, these mostly lack sufficient efficiency and induce toxicities in normal surrounding tissues. Thus, finding new approaches to mitigate side effects and potentially accelerate treatment is paramount. In line with this, increasing preclinical evidence indicates that caloric restriction (CR) and fasting might have anticancer effects by reducing tumor progression, enhancing death of cancer cells, and elevating the effectiveness and tolerability of chemo- and radiotherapies. Nonetheless, clinical studies assessing the potential of CR and fasting in cancer are scarce and inconsistent, and more investigations are still required to clarify their effect in different aspects of cancer treatment. In this review, we have summarized the findings of preclinical and clinical studies of CR and fasting with respect to efficacy and on the adverse effects of standard cancer treatments.

Prevalence and demographic, substance use, and mental health correlates of fasting among U.S. college students

BACKGROUND

Fasting is an unhealthy behavior that has been frequently used as part of weight loss attempts. To date, little research has been conducted to determine the prevalence and substance use and mental health correlates of fasting among college students. Therefore, the aim of this study was to estimate the prevalence and associations between any (≥ 1 time) and regular (≥ 13 times) occurrences of fasting in the past 4 weeks and substance use and mental health correlates among a large sample of college students from 2016 to 2020.

METHODS

Data from four academic survey years (2016-2020; N = 8255) of the national (USA) Healthy Minds Study were analyzed. Unadjusted prevalence of any and regular fasting by survey year and gender was estimated. Multiple logistic regression analyses were conducted to estimate the associations between any and regular fasting and the demographic (age, body mass index, race/ethnicity, sexual orientation, highest parental education), substance use (cigarette use, marijuana use, other illicit drug use, alcohol use), and mental health (depression, anxiety, eating disorder symptoms, suicidal ideation, non-suicidal self-injury) correlates.

RESULTS

Any fasting in the past 4 weeks was common among both men (14.77%) and women (18.12%) and significantly increased from 2016 (10.30%) to 2020 (19.81%) only among men. Regular fasting significantly increased among both men and women from 2016 (men: 1.46%; women: 1.79%) to 2020 (men: 3.53%; women: 6.19%). Among men and women, both any and regular fasting in the past 4 weeks were associated with higher odds of all mental health symptoms, including a positive depression, anxiety, and eating disorder screen, suicidal ideation, and non-suicidal self-injury. Among women, but not men, any and regular fasting in the past 4 weeks were associated with higher odds of marijuana use and other illicit drug use (e.g., cocaine, ecstasy).

CONCLUSIONS

The results from this study underscore both the high and increasing prevalence of fasting among a national sample of college students, as well as the substance use and mental health symptoms associated with this behavior. Healthcare professionals both on and off campus should consider screening for fasting behaviors among college students and provide appropriate intervention when needed.

Multiomics metabolic and epigenetics regulatory network in cancer: A systems biology perspective

Genetic, epigenetic, and metabolic alterations are all hallmarks of cancer. However, the epigenome and metabolome are both highly complex and dynamic biological networks in vivo. The interplay between the epigenome and metabolome contributes to a biological system that is responsive to the tumor microenvironment and possesses a wealth of unknown biomarkers and targets of cancer therapy. From this perspective, we first review the state of high-throughput biological data acquisition (i.e. multiomics data) and analysis (i.e. computational tools) and then propose a conceptual in silico metabolic and epigenetic regulatory network (MER-Net) that is based on these current high-throughput methods. The conceptual MER-Net is aimed at linking metabolomic and epigenomic networks through observation of biological processes, omics data acquisition, analysis of network information, and integration with validated database knowledge. Thus, MER-Net could be used to reveal new potential biomarkers and therapeutic targets using deep learning models to integrate and analyze large multiomics networks. We propose that MER-Net can serve as a tool to guide integrated metabolomics and epigenomics research or can be modified to answer other complex biological and clinical questions using multiomics data.

A Clinical Perspective of Low Carbohydrate Ketogenic Diets: A Narrative Review

Low carbohydrates diets (LCDs), which provide 20–120 g of carbohydrates per day, have long been used as therapeutic options in the treatment of severe obesity, type 2 diabetes mellitus and other morbid conditions, with good results in terms of weight loss and control of the main metabolic parameters, at least in the short and medium term. According to the caloric content and the macronutrient composition, we can classify LCDs in hypocaloric, normoproteic diets [such as the Very Low-Calorie Ketogenic Diet (VLCKD) or the protein-sparing modified fasting (PSMF)], hypocaloric, hyperproteic and hyperlipidic diets (e.g., Atkins, Paleo diets…) and normocaloric, normo-/hyperproteic diets (eucaloric KD), the latter mainly used in patients with brain tumors (gliomas) and refractory epilepsy. In addition to LCD diets, another interesting dietary approach which gained attention in the last few decades is fasting and its beneficial effects in terms of modulation of metabolic pathways, cellular processes and hormonal secretions. Due to the impossibility of using fasting regimens for long periods of time, several alternative strategies have been proposed that can mimic the effects, including calorie restriction, intermittent or alternating fasting, and the so-called fasting mimicking diets (FMDs). Recent preclinical studies have shown positive effects of FMDs in various experimental models of tumors, diabetes, Alzheimer Disease, and other morbid conditions, but to date, the scientific evidence in humans is limited to some opens studies and case reports. The purpose of our narrative review is to offer an overview of the characteristics of the main dietary regimens applied in the treatment of different clinical conditions as well as of the scientific evidence that justifies their use, focusing on low and zero-carb diets and on the different types of fasting.

Ketogenic Diet in Cancer Prevention and Therapy: Molecular Targets and Therapeutic Opportunities

Although cancer is still one of the most significant global challenges facing public health, the world still lacks complementary approaches that would significantly enhance the efficacy of standard anticancer therapies. One of the essential strategies during cancer treatment is following a healthy diet program. The ketogenic diet (KD) has recently emerged as a metabolic therapy in cancer treatment, targeting cancer cell metabolism rather than a conventional dietary approach. The ketogenic diet (KD), a high-fat and very-low-carbohydrate with adequate amounts of protein, has shown antitumor effects by reducing energy supplies to cells. This low energy supply inhibits tumor growth, explaining the ketogenic diet's therapeutic mechanisms in cancer treatment. This review highlights the crucial mechanisms that explain the ketogenic diet's potential antitumor effects, which probably produces an unfavorable metabolic environment for cancer cells and can be used as a promising adjuvant in cancer therapy. Studies discussed in this review provide a solid background for researchers and physicians to design new combination therapies based on KD and conventional therapies.

Metabolomics in cancer research and emerging applications in clinical oncology

Cancer has myriad effects on metabolism that include both rewiring of intracellular metabolism to enable cancer cells to proliferate inappropriately and adapt to the tumor microenvironment, and changes in normal tissue metabolism. With the recognition that fluorodeoxyglucose-positron emission tomography imaging is an important tool for the management of many cancers, other metabolites in biological samples have been in the spotlight for cancer diagnosis, monitoring, and therapy. Metabolomics is the global analysis of small molecule metabolites that like other -omics technologies can provide critical information about the cancer state that are otherwise not apparent. Here, the authors review how cancer and cancer therapies interact with metabolism at the cellular and systemic levels. An overview of metabolomics is provided with a focus on currently available technologies and how they have been applied in the clinical and translational research setting. The authors also discuss how metabolomics could be further leveraged in the future to improve the management of patients with cancer.

Regeneration in starved planarians depends on TRiC/CCT subunits modulating the unfolded protein response

Planarians are able to stand long periods of starvation by maintaining adult stem cell pools and regenerative capacity. The molecular pathways that are needed for the maintenance of regeneration during starvation are not known. Here, we show that down‐regulation of chaperonin TRiC/CCT subunits abrogates the regeneration capacity of planarians during starvation, but TRiC/CCT subunits are dispensable for regeneration in fed planarians. Under starvation, they are required to maintain mitotic fidelity and for blastema formation. We show that TRiC subunits modulate the unfolded protein response (UPR) and are required to maintain ATP levels in starved planarians. Regenerative defects in starved CCT‐depleted planarians can be rescued by either chemical induction of mild endoplasmic reticulum stress, which leads to induction of the UPR, or by the supplementation of fatty acids. Together, these results indicate that CCT‐dependent UPR induction promotes regeneration of planarians under food restriction.

Advancing to the era of cancer immunotherapy

Cancer greatly affects the quality of life of humans worldwide and the number of patients suffering from it is continuously increasing. Over the last century, numerous treatments have been developed to improve the survival of cancer patients but substantial progress still needs to be made before cancer can be truly cured. In recent years, antitumor immunity has become the most debated topic in cancer research and the booming development of immunotherapy has led to a new epoch in cancer therapy. In this review, we describe the relationships between tumors and the immune system, and the rise of immunotherapy. Then, we summarize the characteristics of tumor‐associated immunity and immunotherapeutic strategies with various molecular mechanisms by showing the typical immune molecules whose antibodies are broadly used in the clinic and those that are still under investigation. We also discuss important elements from individual cells to the whole human body, including cellular mutations and modulation, metabolic reprogramming, the microbiome, and the immune contexture. In addition, we also present new observations and technical advancements of both diagnostic and therapeutic methods aimed at cancer immunotherapy. Lastly, we discuss the controversies and challenges that negatively impact patient outcomes.

Starvation and Climate Change—How to Constrain Cancer Cell Epigenetic Diversity and Adaptability to Enhance Treatment Efficacy

Advanced metastatic cancer is currently not curable and the major barrier to eliminating the disease in patients is the resistance of subpopulations of tumor cells to drug treatments. These resistant subpopulations can arise stochastically among the billions of tumor cells in a patient or emerge over time during therapy due to adaptive mechanisms and the selective pressures of drug therapies. Epigenetic mechanisms play important roles in tumor cell diversity and adaptability, and are regulated by metabolic pathways. Here, I discuss knowledge from ecology, evolution, infectious disease, species extinction, metabolism and epigenetics to synthesize a roadmap to a clinically feasible approach to help homogenize tumor cells and, in combination with drug treatments, drive their extinction. Specifically, cycles of starvation and hyperthermia could help synchronize tumor cells and constrain epigenetic diversity and adaptability by limiting substrates and impairing the activity of chromatin modifying enzymes. Hyperthermia could also help prevent cancer cells from entering dangerous hibernation-like states. I propose steps to a treatment paradigm to help drive cancer extinction that builds on the successes of fasting, hyperthermia and immunotherapy and is achievable in patients. Finally, I highlight the many unknowns, opportunities for discovery and that stochastic gene and allele level epigenetic mechanisms pose a major barrier to cancer extinction that warrants deeper investigation.

Metabolic reprogramming and epigenetic modifications on the path to cancer

Metabolic rewiring and epigenetic remodeling, which are closely linked and reciprocally regulate each other, are among the well-known cancer hallmarks. Recent evidence suggests that many metabolites serve as substrates or cofactors of chromatin-modifying enzymes as a consequence of the translocation or spatial regionalization of enzymes or metabolites. Various metabolic alterations and epigenetic modifications also reportedly drive immune escape or impede immunosurveillance within certain contexts, playing important roles in tumor progression. In this review, we focus on how metabolic reprogramming of tumor cells and immune cells reshapes epigenetic alterations, in particular the acetylation and methylation of histone proteins and DNA. We also discuss other eminent metabolic modifications such as, succinylation, hydroxybutyrylation, and lactylation, and update the current advances in metabolism- and epigenetic modification-based therapeutic prospects in cancer.

Hunger brings down the tumor fort

In a recent article published in Molecular Cell, Dai et al. demonstrate that energy stress induced by a ketogenic diet or fasting can enhance checkpoint blockade therapy. Energy stress promotes lysosome-mediated degradation of the immunoinhibitory ligand programmed death-ligand 1 (PDL1) and upregulation of tumor interferon (IFN) responses.

Fasting: How to Guide

Fasting potentials are the most interesting topics in the Nutritional Era. Fasting consists of the catabolism of lipids, proteins, and carbohydrates to maintain blood glucose levels in a normal range. The action mechanisms of fasting were firstly understood in minor organisms and later in humans. Nutritional interventions of caloric restriction could attenuate age-associated epigenetic alterations and could have a protective effect against cellular alterations, promoting longevity and health span. While most fasting studies point out the weight and fat mass decreases, it is important to define specific guidelines for fasting and non-fasting days to enhance adherence, minimize the dropout rates of the interventions, and maximize body composition improvement. Although the panorama of evidence on fasting and caloric restriction is wide, there is a lack of a safe fasting protocol to guide physicians in its prescription. The main goal is to identify a how to use guide, a major posology of fasting, inserted within a huge dietetic personalized strategy leading to an optimal and healthy nutritional status.

Diversity of insulin and IGF signaling in breast cancer: Implications for therapy

This review highlights the significance of the insulin receptor (IR) and insulin-like growth factor-1 receptor (IGF-1R) signaling pathway in cancer and assesses its potential as a therapeutic target. Our emphasis is on breast cancer, but this pathway is central to the behavior of many cancers. An understanding of how IR/IGF-1R signaling contributes to the function of the normal mammary gland provides a foundation for understanding its aberrations in breast cancer. Specifically, dysregulation of the expression and function of ligands (insulin, IGF-1 and IGF-2), receptors and their downstream signaling effectors drive breast cancer initiation and progression, often in a subtype-dependent manner. Efforts to target this pathway for the treatment of cancer have been hindered by several factors including a lack of biomarkers to select patients that could respond to targeted therapy and adverse effects on normal metabolism. To this end, we discuss ongoing efforts aimed at overcoming such obstacles.

Metabolically Supported Chemotherapy for Managing End-Stage Breast Cancer: A Complete and Durable Response

Breast cancer accounts for significant morbidity and mortality worldwide. Currently, treatment options in metastatic breast cancer consist of chemotherapy, along with endocrine, radiation, and/or biological therapies. Although advances in management have improved overall survival times, the treatment options for women with end-stage disease are mostly limited to supportive care. Herein, we present a case report that highlights the response of a 47-year-old premenopausal woman with end-stage (T4N3M1) breast cancer treated with metabolically supported chemotherapy (MSCT), ketogenic diet (KD), hyperthermia (HT), and hyperbaric oxygen therapy (HBOT). The patient first noticed a right breast mass in late 2016, which was initially evaluated and ruled out as a cyst. Skin ulceration was observed in the region of the suspected cyst in May 2017. Subsequent bilateral breast ultrasound identified masses in both breasts and an enlarged right axillary lymph node. The diagnosis following biopsy was grade 3, estrogen receptor-positive (ER+), progesterone receptor-positive (PR+), human epidermal growth factor receptor 2 negative (HER2-), invasive ductal carcinoma of the breast. Initially, the patient refused to receive conventional chemotherapy because of its potential for side effects and toxicity, but she sought medical treatment in August 2018 following extensive disease progression and deterioration of general health. On reevaluation, the patient was considered ineligible for conventional treatment due to her advanced end-stage disease, poor performance status (Eastern Cooperative Oncology Group score: 3), and advanced respiratory symptoms. Exploring other options, the patient was admitted to the ChemoThermia Oncology Center, Istanbul, Turkey in November 2018. At that time, the patient weighed 38 kg (body mass index: 18.1 kg/m²) and had extensive metastatic disease with lesions in the brain, lungs, mediastinum, liver, abdomen, and bones that were detected by magnetic resonance imaging of the brain (with contrast) and whole-body (18F)-fluorodeoxyglucose-positron emission tomography-computed tomography. The patient received a six-month treatment protocol comprised of MSCT, KD, HT, and HBOT, which eliminated all detectable lesions. The therapeutic response was sustained for two years with maintenance treatment comprising KD, dietary supplements, and repurposed medications. This single case report presents evidence of a complete and durable response to a treatment protocol combining MSCT and a novel metabolic therapy in a patient with end-stage breast cancer.

Effects of Calorie Restriction on Health Span and Insulin Resistance: Classic Calorie Restriction Diet vs. Ketosis-Inducing Diet

As the incidence of Chronic Non-Communicable Diseases (CNCDs) increases, preventive approaches become more crucial. In this review, calorie restriction (CR) effects on human beings were evaluated, comparing the benefits and risks of different CR diets: classic CR vs. ketosis-inducing diets, including intermittent fasting (IF), classic ketogenic diet (CKD), fasting mimicking diet (FMD), very-low-calorie ketogenic Diet (VLCKD) and Spanish ketogenic Mediterranean diet (SKMD). Special emphasis on insulin resistance (IR) was placed, as it mediates metabolic syndrome (MS), a known risk factor for CNCD, and is predictive of MS diagnosis. CR is the most robust intervention known to increase lifespan and health span, with high evidence and known biochemical mechanisms. CR improves cardiometabolic risk parameters, boosts exercise insulin sensitivity response, and there may be benefits of implementing moderate CR on healthy young and middle-aged individuals. However, there is insufficient evidence to support long-term CR. CKD is effective for weight and MS management, and may have additional benefits such as prevention of muscle loss and appetite control. SKMD has extreme significance benefits for all the metabolic parameters studied. Studies show inconsistent benefits of IF compared to classic CR. More studies are required to study biochemical parameters, reinforce evidence, identify risks, and seek effective and safe nutritional CR approaches.

SYVN1-MTR4-MAT2A Signaling Axis Regulates Methionine Metabolism in Glioma Cells

Methionine is one of the essential amino acids. How tumor cells adapt and adjust their signal transduction networks to avoid apoptosis in a methionine-restricted environment is worthy of further exploration. In this study, we investigated the molecular mechanism of glioma response to methionine restriction, providing a theoretical basis for new treatment strategies for glioma.

TP53/p53-FBXO22-TFEB controls basal autophagy to govern hormesis

Preconditioning with a mild stressor such as fasting is a promising way to reduce severe side effects from subsequent chemo- or radiotherapy. However, the underlying mechanisms have been largely unexplored. Here, we demonstrate that the TP53/p53-FBXO22-TFEB (transcription factor EB) axis plays an essential role in this process through upregulating basal macroautophagy/autophagy. Mild stress-activated TP53 transcriptionally induced FBXO22, which in turn ubiquitinated KDM4B (lysine-specific demethylase 4B) complexed with MYC-NCOR1 suppressors for degradation, leading to transcriptional induction of TFEB. Upregulation of autophagy-related genes by increased TFEB dramatically enhanced autophagic activity and cell survival upon following a severe stressor. Mitogen-induced AKT1 activation counteracted this process through the phosphorylation of KDM4B, which inhibited FBXO22-mediated ubiquitination. Additionally, fbxo22^-/- mice died within 10 h of birth, and their mouse embryonic fibroblasts (MEFs) showed a lowered basal autophagy, whereas FBXO22-overexpressing mice were resistant to chemotherapy. Taken together, these results suggest that TP53 upregulates basal autophagy through the FBXO22-TFEB axis, which governs the hormetic effect in chemotherapy.Abbreviations: BBC3/PUMA: BCL2 binding component 3; CDKN1A/p21: cyclin dependent kinase inhibitor 1A; ChIP-seq: chromatin immunoprecipitation followed by sequencing; DDB2: damage specific DNA binding protein 2; DRAM: DNA damage regulated autophagy modulator; ESR/ER: estrogen receptor 1; FMD: fasting mimicking diet; HCQ: hydroxychloroquine; KDM4B: lysine-specific demethylase 4B; MAP1LC3/LC3: microtubule associated protein 1 light chain 3 alpha; MEFs: mouse embryonic fibroblasts; MTOR: mechanistic target of rapamycin kinase; NCOR1: nuclear receptor corepressor 1; SCF: SKP1-CUL-F-box protein; SQSTM1: sequestosome 1; TFEB: transcription factor EB.

Metabolomics, metabolic flux analysis and cancer pharmacology

Metabolic reprogramming is a hallmark of cancer and increasing evidence suggests that reprogrammed cell metabolism supports tumor initiation, progression, metastasis and drug resistance. Understanding metabolic dysregulation may provide therapeutic targets and facilitate drug research and development for cancer therapy. Metabolomics enables the high-throughput characterization of a large scale of small molecule metabolites in cells, tissues and biofluids, while metabolic flux analysis (MFA) tracks dynamic metabolic activities using stable isotope tracer methods. Recent advances in metabolomics and MFA technologies make them powerful tools for metabolic profiling and characterizing metabolic activities in health and disease, especially in cancer research. In this review, we introduce recent advances in metabolomics and MFA analytical technologies, and provide the first comprehensive summary of the most commonly used isotope tracing methods. In addition, we highlight how metabolomics and MFA are applied in cancer pharmacology studies particularly for discovering targetable metabolic vulnerabilities, understanding the mechanisms of drug action and drug resistance, exploring potential strategies with dietary intervention, identifying cancer biomarkers, as well as enabling precision treatment with pharmacometabolomics.