A cross-sectional study of carnitine deficiency and fatigue in pediatric cancer patients

l-Carnitine and Acetyl-l-Carnitine Induce Metabolism Alteration and Mitophagy-Related Cell Death in Colorectal Cancer Cells

Background/Objectives: Colorectal cancer (CRC) remains one of the most common and deadly malignancies worldwide, driven by metabolic reprogramming and mitochondrial dysfunction, which support tumor growth and progression. Several studies showed that nutrition is a contributing factor in the prevention and management of CRC. In this context, carnitines, amino acid derivatives abundant in food of animal origin, such as meat and milk, are crucial for mitochondrial function. Recently, l-carnitine and acetyl-l-carnitine have received particular attention due to their antioxidant, anti-inflammatory, and antitumor properties. However, to date, there is no conclusive evidence on the effects of l-carnitine and acetyl-l-carnitine in CRC or the underlying molecular mechanism. Methods: In this study, we investigated in HCT 116 and HT-29 CRC cells the effects of l-carnitine and acetyl-l-carnitine on mitochondrial homeostasis by XF HS Seahorse Bioanalyzer and cell death pathways by flow cytometry and western blot assays. Results: Data showed that l-carnitine and acetyl-l-carnitine reduced cell viability (p < 0.001), modulated cellular bioenergetics, and induced oxidative stress (p < 0.001). These phenomena promoted autophagic flux and the mitophagy process via PINK1 and Parkin modulation after 72 h of treatment. Of note, the combined treatment with l-carnitine and acetyl-l-carnitine showed a synergistic effect and enhanced the effect of single carnitines on tumor cell growth and metabolic dysfunction (p < 0.05). Moreover, exposure to l-carnitine and acetyl-l-carnitine promoted CRC cell apoptosis, suggesting a mechanism involving mitophagy-related cell death. These data were associated with increased SIRT4 expression levels (p < 0.01) and the activation of AMPK signaling (p < 0.01). Conclusions: Overall, the results, by supporting the importance of nutritional factors in CRC management, highlight l-carnitine and acetyl-l-carnitine as promising agents to target CRC metabolic vulnerabilities.

Clinical Significance of Carnitine in the Treatment of Cancer: From Traffic to the Regulation

Metabolic reprogramming is a common hallmark of cancer cells. Cancer cells exhibit metabolic flexibility to maintain high proliferation and survival rates. In other words, adaptation of cellular demand is essential for tumorigenesis, since a diverse supply of nutrients is required to accommodate tumor growth and progression. Diversity of carbon substrates fueling cancer cells indicate metabolic heterogeneity, even in tumors sharing the same clinical diagnosis. In addition to the alteration of glucose and amino acid metabolism in cancer cells, there is evidence that cancer cells can alter lipid metabolism. Some tumors rely on fatty acid oxidation (FAO) as the primary energy source; hence, cancer cells overexpress the enzymes involved in FAO. Carnitine is an essential cofactor in the lipid metabolic pathways. It is crucial in facilitating the transport of long-chain fatty acids into the mitochondria for β-oxidation. This role and others played by carnitine, especially its antioxidant function in cellular processes, emphasize the fine regulation of carnitine traffic within tissues and subcellular compartments. The biological activity of carnitine is orchestrated by specific membrane transporters that mediate the transfer of carnitine and its derivatives across the cell membrane. The concerted function of carnitine transporters creates a collaborative network that is relevant to metabolic reprogramming in cancer cells. Here, the molecular mechanisms relevant to the role and expression of carnitine transporters are discussed, providing insights into cancer treatment.

Hypoglycemia Due to Acquired Carnitine Deficiency in a Pediatric Patient Receiving Chemotherapy

We describe a 21-month-old male with relapsed clear cell sarcoma of the kidney receiving enteral nutrition who experienced recurrent, ketotic hypoglycemia. During relapse therapy, he had recurrent hypoglycemia episodes, in the setting of hematochezia and diarrhea. Evaluation revealed low carnitine levels. He received supplementation with oral levocarnitine throughout the remainder of treatment, resulting in normalization of serum carnitine levels and no further hypoglycemia. We believe adverse effects of the chemotherapy on his single kidney and gastrointestinal insult resulted in hypoglycemia and carnitine deficiency. Our case highlights that carnitine deficiency should be considered when acute onset hypoglycemia without obvious cause occurs.

The predictive trifecta? Fatigue, pain, and anxiety severity forecast the suffering profile of children with cancer

BACKGROUND

Fatigue, pain, and anxiety, symptoms commonly experienced by children with cancer, may predict pediatric symptom suffering profile membership that is amenable to treatment.

METHODS

Three latent profiles (Low, Medium, and High symptom suffering) from 436 pediatric patients undergoing cancer care were assessed for association with three single-item symptoms and socio-demographic variables.

RESULTS

Pediatric-PRO-CTCAE fatigue, pain, and anxiety severity scores at baseline were highly and significantly associated with the Medium and High Suffering profiles comprised of PROMIS pediatric symptom and function measures. The likelihood of membership in the Medium Suffering group was 11.37 times higher for patients who experienced fatigue severity than those with did not, while experience of pain severity increased the likelihood of the child's membership in the Medium Suffering profile by 2.59 times and anxiety by 3.67 times. The severity of fatigue increased the likelihood of presence in the High Suffering group by 2.99 times while pain severity increased the likelihood of the child's membership in the High Suffering profile by 6.36 times and anxiety by 16.75 times. Controlling for experience of symptom severity, older patients were more likely to be in the Higher or Medium Suffering profile than in the Low Suffering profile; no other socio-demographic or clinical variables had a significant effect on the latent profile classification.

CONCLUSION

Clinician knowledge of the strong association between fatigue, pain, and anxiety severity and suffering profiles may help focus supportive care to improve the cancer experience for children most at risk from time of diagnosis through treatment.

The Symptom Experience in Pediatric Cancer: Current Conceptualizations and Future Directions

PURPOSE OF REVIEW

We aimed to review the recent research on the childhood cancer symptom experience pertaining to socioeconomic factors, biology and genetics, growth and development, family psychosocial dynamics, and social and treating environments to begin to formulate recommendations for a personalized approach to symptom management.

RECENT FINDINGS

Cancer symptoms are common and distressing in children and negatively impact child and family quality of life. Many interacting factors influence children's cancer symptoms experiences, including the assessment and management of such symptoms. This paper highlights several gaps in the research related to the cancer symptom experience including routine symptom assessment, the impact of socioeconomic, biological, and genetic factors on symptoms, and the establishment of effective symptom management partnerships with families. Based on our findings, we provide recommendations related to that research which is ready to be implemented into clinical practice and areas for needed future efforts.

Symptoms in Children Receiving Treatment for Cancer-Part I: Fatigue, Sleep Disturbance, and Nausea/Vomiting

Children and adolescents with cancer often undergo intensive chemotherapy treatment to obtain remission and long-term survival. The pursuit of successful treatment outcomes may lead to high levels of symptom distress related to treatment side effects and toxicities. The Children's Oncology Group Nursing Discipline held a State of the Science Symposium "Symptom Assessment During Childhood Cancer Treatment" in 2018 that included reviews of evidence regarding key symptoms. The purpose of this review is to summarize and synthesize the evidence presented about the prevalence, relationships, trajectories, and associated biomarkers of selected symptoms experienced by children and adolescents during cancer treatment. Five symptoms were selected, with the focus on fatigue, sleep disturbance, and nausea/vomiting and included in Part I of the review. Using Ovid-Medline, studies published between 2008 and 2018 that focused on these specific symptoms during active chemotherapy treatment were selected. Fatigue interferes with normal developmental activities and is associated with sleep disturbances, and its pattern changes within a cycle of chemotherapy as well as across the treatment trajectory. Sleep is disrupted by the hospital environment, treatment medications, and changes in normal childhood and schedules. Disturbances of sleep persist during treatment, preventing recovery from poor quality sleep. Although pharmacologic interventions have advanced for treatment of nausea and vomiting, children and adolescents continue to struggle with this symptom. Its trajectory changes with the intensity of treatment, and over half of the patients report that they experience nausea and/or vomiting. Future research is needed to advance identification of biologic risk factors for symptoms and test effectiveness of symptom-related interventions.