Overnight fasting before lapatinib administration to breast cancer patients leads to reduced toxicity compared with nighttime dosing: a retrospective cohort study from a randomized clinical trial

Intermittent fasting and its impact on toxicities, symptoms and quality of life in patients on active cancer treatment

Intermittent fasting is a dietary intervention that is increasingly being tested for positive outcomes in patients receiving cancer treatment. In this review, we examine the impact of intermittent fasting on symptoms, toxicities, and quality of life in patients undergoing cancer therapy and highlight unmet investigative areas to prompt future research. While current evidence is preliminary and conclusions mixed, some promising clinical studies suggest that intermittent fasting interventions may improve fatigue and reduce gastrointestinal toxicities in certain patients with cancer. Emerging clinical evidence also demonstrates that intermittent fasting may reduce off-target DNA damage, and induce favorable cellular-level immune remodeling. Furthermore, intermittent fasting has the potential to lower hyperglycemia and the ratio of fat to lean body mass, which may benefit patients at risk of hyperglycemia and weight-related adverse effects of some common pharmacological cancer treatments. Larger controlled studies are necessary to evaluate intermittent fasting in relation to these endpoints and determine the effectiveness of intermittent fasting as an adjunct intervention during cancer care. Future cancer trials should evaluate intermittent fasting diets in the context of multimodal diet, exercise, and nutrition strategies, and also evaluate the impact of intermittent fasting on other important areas such as the circadian system and the gut microbiome.

Considering the Oral Bioavailability of Protein Kinase Inhibitors: Essential in Assessing the Extent of Drug-Drug Interaction and Improving Clinical Practice

Protein kinase inhibitors share pharmacokinetic (PK) pathways among themselves. They are all metabolized by several cytochromes P450 (CYP). For most of them, CYP3A4 is the predominant metabolic pathway. However, their oral bioavailability differs. For example, the oral bioavailability of imatinib has been estimated at nearly 100%, but that of ibrutinib averages 3% due to its high hepatic first-pass effect. Overall, the smaller the oral bioavailability, the larger its interindividual PK variability. Indeed, for drugs with low oral bioavailability, the extent of their absorption is an additional cause (along with elimination variability) of differences in drug exposure among patients. The impact of drug-drug interaction (DDI) also differs between drugs with low or high oral bioavailability. We describe and explain why the impact of CYP3A4 inhibitors and inducers is much greater for protein kinase inhibitors with low oral bioavailability. The effect of food on protein kinase inhibitors and DDIs corresponding to plasma protein binding will also be considered. Finally, the benefits of these concepts in clinical practice (including therapeutic drug monitoring) will be discussed. Overall, our main objective was to apply fundamental PK concepts to understanding the main clinical issues of these oral anticancer drugs.

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.