Ketogenic Diet and Potential Applications for Cancer Therapy Lorenzo Cohen, PhD Jennifer McQuade, MD, LAc Stephanie Maxson, MS, RD September 12, 2014 Ketogenic Diet - History • • • • Hippocrates recommended fasting for seizure therapy First scientific publication – France, 1911 First efficacy studies of ketogenic diet for epilepsy – US 1925 Interest waned in 1938 with phenytoin, then renewed ~1990 Ketogenic Diet • Composition: – High fat – Very low CHO (<50 gm/day) – Adequate protein • Increases reliance on fatty acids instead of glucose → mimics fasting • Low serum glucose during fasting triggers hormone changes → lipolysis • Free fatty acids then converted to ketone bodies in liver – acetoacetate and β-hydroxybutyrate Indications • Indications: – Intractable epilepsy, all ages. Mechanism unknown. – Inborn metabolic disorders ie. pyruvate dehydrogenase complex deficiency • Experimental Uses: – – – – – DM type 2 PCOS Autism Bipolar disorder Cancers, especially brain and skin • Contraindications: – Fatty acid oxidation defects – Primary carnitine deficiency Adverse Effects • Short-term: – – – – Hypoglycemia Acidosis Dehydration, poor appetite Constipation, diarrhea • Long-term: – – – – – Growth retardation Micronutrient deficiencies Hypertriglyceridemia Renal stones Irritability, lethargy • Serious but rare: – Acute pancreatitis – Cardiomyopathy – Acute hemolytic anemia Diet Details • KD typically 4:1 or 3:1 – gm fat : gm protein + gm CHO – Lower ratios to better meet protein requirements or improve tolerance – Compared to standard diet (25% fat, 20% protein, 55% CHO) → 1:6.7 • Menus are calculated to the nearest gram • Foods weighed to the nearest 10th gm • Typically includes high fat foods: heavy cream, sour cream, butter, margarine, oil, mayonnaise • Protein sources added second • Very limited portions of CHO foods, including fruits and vegetables, added last. KD Mechanisms- Epilepsy • Epilepsy– Metabolic changes likely related to the KD’s anticonvulsant properties include – but are not limited to – ketosis, reduced glucose, elevated fatty acid levels, and enhanced bioenergetic reserves. Direct neuronal effects induced by the KD may involve ATP-sensitive potassium (KATP) channel modulation, enhanced purinergic (i.e., adenosine) and GABAergic neurotransmission, increased brain-derived neurotrophic factor (BDNF) expression consequent to glycolytic restriction, attenuation of neuroinflammation, as well as an expansion in bioenergetic reserves and stabilization of the neuronal membrane potential through improved mitochondrial function. – Direct role of ketones in decreasing neuronal excitation- “available evidence thus far fails to strongly support a primary mechanistic role for ketone bodies” SHORT ANSWER= WE DON’T KNOW Fig. 4 Decreased metabolism of glucose by tumors, visualized by PET with the glucose analog FDG, predicts response to anticancer therapy. M G Vander Heiden et al. Science 2009;324:1029-1033 Published by AAAS Fig. 2 Schematic representation of the differences between oxidative phosphorylation, anaerobic glycolysis, and aerobic glycolysis (Warburg effect). M G Vander Heiden et al. Science 2009;324:1029-1033 Published by AAAS Fig. 3 Metabolic pathways active in proliferating cells are directly controlled by signaling pathways involving known oncogenes and tumor suppressor genes. M G Vander Heiden et al. Science 2009;324:1029-1033 Published by AAAS Klement 2014 Metabolic heterogeneity vs. inflexibility • Differential stress response – Particularly in brain - Debarardinis- UTSW - NSCLC- C13 infusion during surgery- both glycolysis and tca inc relative to normal tissues- regional heterogeneityglycolysis correlates with compromised perfusion -High OxPhos as mechanism of resistance Calorie restriction vs. ketogenic diet • Very little evidence for direct anti-tumor effect of ketones • Tolerability Gastric cancer cell line 2312/87 relies on glycolysis In vivo study design • 24 nude mice-> 12 KD + 12 SD • Cages of 6 animals • Hind flank innoculation of gastric cancer cell line 2312/87 • Dietary intervention began same day as inoculation • Ad libitum access to their diet • Endpoint: Tumour volume 600 -700 mm3 • Survival time: Interval between subcutaneous tumour cell inoculation and the endpoint In vivo study design • • • • • • • • • 40.7% curd cheese 19.9% mackerel 8.1% blue veined cheese, 8.1% white veined cheese 8.1% bacon 4.0% Tavarlin bread MCT 21.45% 8.1% flaxseed 2.7% sesame seed 300 ml of Tavarlin oil (28.7% saturated fatty acids, 35.7% unsaturated fatty acids, and 35.6% polyunsaturated fatty acids with a ratio of omega-6/omega-3 of 1.77:1) • 100 ml Tavarlin lactate drink Ketogenic diet significantly decreases rate of tumor growth Ketogenic diet influences tumor “take” Ketogenic diet significantly prolongs“survival” P=0.001 Impact on body weight, ketosis, glucose, insulin β-OHB levels : 1.3 ± 0.5 mmol/l KD vs. 0.6 ± 0.1 mmol/l SD (P < 0.001) Glucose levels: 5.5 ± 2.7 mmol/l KD vs. 6.3 ± 1.3 mmol/l SD (P = 0.59) Insulin levels: 63.3 ± 32.5 pmol/l KD vs. 72.0 ± 41.0 pmol/l SD (P=0.84) MCT KD anti-cancer, but why? • Most studies of ketogenic diet are in fact studies of calorie restricted ketogenic diet and evidence for CRKD antitumor effects strong whereas mixed for ad libitum KD • Decrease in Insulin/IGF/Glucose more consistent in calorie restriction studies • Is it anti-tumor effects of the Omega-3’s and MCT? • Anti-angiogenic – good fats or reduced pyruvate-> dec HIF-1 activation of VEGF – “Metabolic catastrophe” The “Products” ERGO: A pilot study of ketogenic diet in recurrent glioblastoma J. Rieger, O. Bahr, GD Maurer, et al. International Journal of Oncology (2014)44:1843-52. • Primary Objective: feasibility of ketogenic diet in glioblastoma patients • Secondary Objectives: – – – – – Diet safety Percentage of patients achieving ketosis Quality of life Progression-free survival Overall survival Human Study • Prospective, open-label, single-arm pilot • Inclusion criteria: – Age ≥ 18yo – Relapse ≥ 6 months after initial surgery AND ≥ 3 months after completion of radiation – Relapse during OR after temozolomide – No other reasonable chemo options OR chemo refused – Karnofsky performance score (KPS) ≥ 60% • Exclusion criteria: – DM requiring insulin OR cardiac insufficiency - 12.5 months – median time from dx to start of study treatment (6-42 mos.) Ketogenic Diet • 60 grams CHO/day → estimated 1.4:1 • No calorie restriction – Instructed to eat to satiety • Fermented yogurt drink: 500ml/day • 2 plant oils: – “basic” oil and “addition” oil (99% fat) • No standardized meal plan – Instructed on keto diet – Provided recipes and written instructions – Subjects prepared own meals Data Collection • Assessed at baseline, follow-ups (6-8 week intervals), and clinical progression : – – – – seizures, medications, vitals Glu, HbA1c, triglycerides, cholesterol, LDL, HDL KPS, mini-mental status, QOL questionnaire Neurological examination Data Collection (cont) • Subjects collected: – Urine ketones 2-3 times per week – “Nutritional plan” • Weekly questionnaire (scale of 0-3): – Diarrhea/constipation – Hunger – Glucose demand • MRI: q6-8 weeks or with clinical progression – Response or stable → continue diet – Progression → “allowed” to continue diet with salvage therapy – Progression with combination → diet discontinued - 20 subjects enrolled (12/07-3/10) Safety/Tolerability • Followed diet avg 6.8 days/wk • No serious adverse events • Majority w/ no const./diarrhea • Hunger first week but improved following weeks Efficacy For all subjects: • Median time to progression: 5 weeks (3-13) • Median overall survival after start of diet: 32 weeks (6-86+) • Trend for longer PFS in subjects with stable ketosis (>50%) Efficacy (cont) • Progression in all 17 subjects • 7 continued diet with bevacizumab salvage therapy – 1 complete response and 5 partial responses → Overall response of 85% – compared these subjects to a cohort of 28 patients treated with bev at same institution without ketogenic diet- ORR 65% (p=0.4). These response rates are both significantly higher than those reported in the Phase II trials of bev salvage (28-40%) Efficacy (cont) • Median PFS from bev: – with keto diet: 20.1 weeks (12-124) – without keto diet: 16.1 weeks (4-90+) (p=0.38, 95% CI 15-17wk) Mouse Study • Does keto diet modulate the efficacy of bevacizumab? • Pilot study combining keto diet with bev in mice – 44 female, athymic mice – Glioma cells implanted into right striatum – ad lib food and water – randomized to standard CHO-rich diet OR keto diet (3.14:1) – twice weekly intraperitoneal injections of bev OR saline (starting day 12) Methods • Day 24, 5-7 animals per group: β-hydroxybutyrate • Day 28, 3 animals per group: – tumor measured by MRI – bioluminescence imaging to map concentrations: • ATP • lactate • glucose • Remainder sacrificed at onset of symptoms OR loss of >20% weight • KD alone had no effect on survival. • Combined bev and KD prolonged survival significantly compared to bev alone • Tumor volume tended to be smaller with combination bev and KD (p<0.05) • Bev sig. reduced ATP in tumor tissue; trend for stronger effect in mice fed KD Conclusion • Keto diet is feasible and safe, but probably has no significant clinical activity when used as single agent in recurrent glioma. Discussion: • Diets poorly monitored and documented • Diet ratio moderately ketogenic • CHO limits not individualized • No sig change in glucose; related to steroids? Discussion • • • • • Ketogenic versus calorie restriction? Feasibility of maintaining a ketogenic diet? Role of specific fats – any fat or ideal to have MCT? Is it the high fat that matters or just low carbs/GL? More relevant for some cancers (e.g., brain)?