Metabolic reprogramming has been identified as a hallmark of cancer. Almost a century after Otto Warburg initially discovered increased glycolytic activity in tumor tissue ("Warburg effect"), therapeutic targeting of cancer metabolism has become a field of intense research effort in cancer biology.

A growing appreciation of metabolic heterogeneity and complexity is currently reshaping investigators "simplistic" understanding of metabolic reprogramming in cancer. Discovering metabolic vulnerabilities as new treatment targets for cancer requires systematic dissection of metabolic dependencies, fuel preferences, and underlying mechanisms in the specific physiological context. However, today's data on cancer cell metabolic signatures and heterogeneity in their physiological habitat of the human organism is sparse to non-existent representing a critical knowledge gap in designing effective metabolic therapies. Here, the investigators propose a "top-down" approach studying cancer cell metabolism in patients followed by mechanistic in-depth studies in cell culture and animal models to define metabolic vulnerabilities.

Investigators will develop a metabolic tracing method to quantitatively characterize metabolic signatures and fuel preferences of leukemic lymphocytes in patients with chronic lymphocytic leukemia (CLL). Isotopic metabolic tracers are nutrients that are chemically identical to the native nutrient. Incorporated stable, non-radioactive isotopes allow investigators to follow their metabolic fate by monitoring conversion of tracer nutrients into downstream metabolites using cutting-edge metabolomics analysis. Using this method, investigators propose to test the hypothesis that leukemic lymphocytes show tissue-specific metabolic preferences that differ from non-leukemic lymphocytes and that ex vivo in-plasma labeling represents a useful model for assaying metabolic activity in leukemic cells in a patient-specific manner.

Inclusion Criteria:

Group A

• Adult (18 years of age or older)
• No previous history of cancer
• Routine history of normal blood counts and vital signs
• Documented Informed Consent

Group B

• Adult (18 years of age or older)
• Diagnosis of CLL with low disease burden defined as Rai stage 0 ((Lymphocytosis; no enlargement of the lymph nodes, spleen, or liver; red blood cell and platelet counts are near normal.)
• Treatment naïve
• Documented Informed Consent

Group C

• Adult (18 years of age or older)
• Diagnosis of CLL with high systemic disease burden defined as infiltration of bone marrow causing cytopenia
• Treatment naïve
• Able/willing to have bone marrow aspiration
• Documented Informed Consent

Exclusion Criteria:

For all participants

• Prisoners
• Psychiatric inpatients or people who are institutionalized
• Minor (Less than 18 years of age)
• History of diabetes
• Cannot be on antihyperglycemic therapy
• Carbohydrate restricting diets: Atkins, Vegan, Ketogenic, etc.
• Females of child bearing potential
• Persons without decision-making capacity
• Person who cannot read/write English
• Not meeting inclusion criteria defined above

To meet the study aims sixteen (16) adult participants will be enrolled: four (4) healthy volunteers defined as people without a history of cancer, 8 patients with low disease burden CLL (Chronic Lymphocytic Leukemia) defined as confined to Rai stage 0, and 4 patients with high disease burden CLL defined as having extensive infiltration of the bone marrow.