Phase I dose-finding study for melatonin in pediatric oncology patients with relapsed solid tumors

Melatonin alters the excitability of mouse cerebellar granule neurons by inhibiting voltage-gated sodium, potassium, and calcium channels

Besides its role in the circadian rhythm, the pineal gland hormone melatonin (MLT) also possesses antiepileptogenic, antineoplastic, and cardioprotective properties, among others. The dosages necessary to elicit beneficial effects in these diseases often far surpass physiological concentrations. Although even high doses of MLT are considered to be largely harmless to humans, the possible side effects of pharmacological concentrations are so far not well investigated. In the present study, we report that pharmacological doses of MLT (3 mM) strongly altered the electrophysiological characteristics of cultured primary mouse cerebellar granule cells (CGCs). Using whole-cell patch clamp and ratiometric Ca2+ imaging, we observed that pharmacological concentrations of MLT inhibited several types of voltage-gated Na+ , K+ , and Ca2+ channels in CGCs independently of known MLT-receptors, altering the character and pattern of elicited action potentials (APs) significantly, quickly and reversibly. Specifically, MLT reduced AP frequency, afterhyperpolarization, and rheobase, whereas AP amplitude and threshold potential remained unchanged. The altered biophysical profile of the cells could constitute a possible mechanism underlying the proposed beneficial effects of MLT in brain-related disorders, such as epilepsy. On the other hand, it suggests potential adverse effects of pharmacological MLT concentrations on neurons, which should be considered when using MLT as a pharmacological compound.

Relevance of Dietary Supplement Use in Gastrointestinal-Cancer-Associated Cachexia

Cancer cachexia is a multi-organ syndrome with unintentional weight loss, sarcopenia, and systemic inflammation. Gastrointestinal (GI) cancer patients are more susceptible to cachexia development due to impaired nutrient absorption and digestion. Given the widespread availability and relatively low cost of dietary supplements, we examined the evidence and effects of fish oil (omega-3 fatty acids), melatonin, probiotics, and green tea for managing symptoms of GI cancer cachexia. A literature review of four specific supplements was conducted using PubMed, Google Scholar, and CINAHL without a date restriction. Of 4621 available literature references, 26 articles were eligible for review. Fish oil decreased C-reactive protein and maintained CD4+ cell count, while melatonin indicated inconsistent findings on managing cachexia, but was well-tolerated. Probiotics decreased serum pro-inflammatory biomarkers and increased the tolerability of chemotherapy by reducing side effects. Green tea preparations and extracts showed a decreased risk of developing various cancers and did not impact tumor growth, survival, or adverse effects. Among these four supplements, probiotics are most promising for further research in preventing systemic inflammation and maintaining adequate absorption of nutrients to prevent the progression of cancer cachexia. Supplements may benefit treatment outcomes in cancer cachexia without side effects while supporting nutritional and therapeutic needs.

Hypoxia and HIFs in Ewing sarcoma: new perspectives on a multi-facetted relationship

Hypoxia develops during the growth of solid tumors and influences tumoral activity in multiple ways. Low oxygen tension is also present in the bone microenvironment where Ewing sarcoma (EwS) - a highly aggressive pediatric cancer - mainly arises. Hypoxia inducible factor 1 subunit alpha (HIF-1-a) is the principal molecular mediator of the hypoxic response in cancer whereas EWSR1::FLI1 constitutes the oncogenic driver of EwS. Interaction of the two proteins has been shown in EwS. Although a growing body of studies investigated hypoxia and HIFs in EwS, their precise role for EwS pathophysiology is not clarified to date. This review summarizes and structures recent findings demonstrating that hypoxia and HIFs play a role in EwS at multiple levels. We propose to view hypoxia and HIFs as independent protagonists in the story of EwS and give a perspective on their potential clinical relevance as prognostic markers and therapeutic targets in EwS treatment.

Is Melatonin the “Next Vitamin D”?: A Review of Emerging Science, Clinical Uses, Safety, and Dietary Supplements

Melatonin has become a popular dietary supplement, most known as a chronobiotic, and for establishing healthy sleep. Research over the last decade into cancer, Alzheimer’s disease, multiple sclerosis, fertility, PCOS, and many other conditions, combined with the COVID-19 pandemic, has led to greater awareness of melatonin because of its ability to act as a potent antioxidant, immune-active agent, and mitochondrial regulator. There are distinct similarities between melatonin and vitamin D in the depth and breadth of their impact on health. Both act as hormones, affect multiple systems through their immune-modulating, anti-inflammatory functions, are found in the skin, and are responsive to sunlight and darkness. In fact, there may be similarities between the widespread concern about vitamin D deficiency as a “sunlight deficiency” and reduced melatonin secretion as a result of “darkness deficiency” from overexposure to artificial blue light. The trend toward greater use of melatonin supplements has resulted in concern about its safety, especially higher doses, long-term use, and application in certain populations (e.g., children). This review aims to evaluate the recent data on melatonin’s mechanisms, its clinical uses beyond sleep, safety concerns, and a thorough summary of therapeutic considerations concerning dietary supplementation, including the different formats available (animal, synthetic, and phytomelatonin), dosing, timing, contraindications, and nutrient combinations.

Pediatric Patients and Dietary Choices: Examining Alternative Options, Decision Making, and Misinformation

BACKGROUND

Nutrition is a key component of oncologic therapies and treatments. Patients and families are interested in the integration of alternative diets to promote therapy response as well as counteract the cancer. With the expansion of online and social media presence comes the endorsement of nonscientific claims.

OBJECTIVES

The purpose of this article is to review alternative diets and discuss the basis of good nutrition in pediatric patients with cancer. This article will also explore where patients and families are likely to seek their information and assess their level of trust in the information.

METHODS

Five alternative diets and two supplements were assessed through a literature review for their effect on pediatric patients with cancer.

FINDINGS

Additional research is needed to prove consistent and definitive dietary benefits for pediatric patients with cancer; however, some diets have demonstrated promising results. A general diet for pediatric patients with cancer consists of an appropriate distribution of nutritious carbohydrates, proteins, and fats. However, unregulated sources of information remain a risk.

The emergence of melatonin in oncology: Focus on colorectal cancer

Within the last few decades, melatonin has increasingly emerged in clinical oncology as a naturally occurring bioactive molecule with substantial anticancer properties and a pharmacological profile optimal for joining the currently available pharmacopeia. In addition, extensive experimental data shows that this chronobiotic agent exerts oncostatic effects throughout all stages of tumor growth, from initial cell transformation to mitigation of malignant progression and metastasis; additionally, melatonin alleviates the side effects and improves the welfare of radio/chemotherapy-treated patients. Thus, the support of clinicians and oncologists for the use of melatonin in both the treatment and proactive prevention of cancer is gaining strength. Because of its epidemiological importance and symptomatic debut in advanced stages of difficult clinical management, colorectal cancer (CRC) is a preferential target for testing new therapies. In this regard, the development of effective forms of clinical intervention for the improvement of CRC outcome, specifically metastatic CRC, is urgent. At the same time, the need to reduce the costs of conventional anti-CRC therapy results is also imperative. In light of this status quo, the therapeutic potential of melatonin, and the direct and indirect critical processes of CRC malignancy it modulates, have aroused much interest. To illuminate the imminent future on CRC research, we focused our attention on the molecular mechanisms underlying the multiple oncostatic actions displayed by melatonin in the onset and evolution of CRC and summarized epidemiological evidence, as well as in vitro, in vivo and clinical findings that support the broadly protective potential demonstrated by melatonin.