Effectiveness of glutamine for the treatment of radiodermatitis in cancer patients: a meta-analysis of randomized controlled trials

BACKGROUND

After receiving radiation therapy, 60%-95% of patients with cancer develop radiodermatitis, which causes pain, wound infection, and poor quality of life. Glutamine is a popular nutritional supplement for patients with cancer. Several studies examined the usefulness of glutamine for reducing radiodermatitis. However, there is still no consolidated evidence for clinical use.

METHODS

We searched PubMed, Embase, Cochrane Library, CINAHL PLUS, and the China Knowledge Resource Integrated Database for the relevant literature published up to March 2023, without language restrictions. Two reviewers screened, filtered, and appraised these articles independently, and their data were pooled using a random-effects model.

RESULTS

Five randomized controlled trials (RCTs) with 218 participants were analyzed. The incidence of radiodermatitis in the glutamine group (89/110) was significantly lower than in the placebo group (99/108; risk ratio [RR], 0.90; 95% CI, 0.81-1.00; p = 0.05; I2 = 7%). The incidence of moderate to severe radiodermatitis was significantly lower in the glutamine group than in the placebo group (RR, 0.49; 95% CI, 0.32-0.76; p = 0.001; I2 = 52%). Moreover, subgroup analysis demonstrated heterogeneity (I2 = 52%) for moderate to severe radiodermatitis, the risk of which might be significantly reduced by a glutamine dose of 20-30 g/day (RR, 0.60; 95% CI, 0.41-0.87; I2 = 0%).

CONCLUSION

The meta-analysis indicate that glutamine might lead to a lower incidence of radiodermatitis, and that a glutamine dose of 20-30 g/day might decrease the incidence of moderate to severe dermatitis. Thus, the serious impact of radiodermatitis on treatment follow-up makes the clinical use of glutamine even more important. PROSPERO number: CRD42021254394.

Combination L-Glutamine with Gemcitabine and Nab-Paclitaxel in Treatment-Naïve Advanced Pancreatic Cancer: The Phase I GlutaPanc Study Protocol

Advanced pancreatic cancer is underscored by progressive therapeutic resistance and a dismal 5-year survival rate of 3%. Preclinical data demonstrated glutamine supplementation, not deprivation, elicited antitumor effects against pancreatic ductal adenocarcinoma (PDAC) alone and in combination with gemcitabine in a dose-dependent manner. The GlutaPanc phase I trial is a single-arm, open-label clinical trial investigating the safety of combination L-glutamine, gemcitabine, and nab-paclitaxel in subjects (n = 16) with untreated, locally advanced unresectable or metastatic pancreatic cancer. Following a 7-day lead-in phase with L-glutamine, the dose-finding phase via Bayesian design begins with treatment cycles lasting 28 days until disease progression, intolerance, or withdrawal. The primary objective is to establish the recommended phase II dose (RP2D) of combination L-glutamine, gemcitabine, and nab-paclitaxel. Secondary objectives include safety of the combination across all dose levels and preliminary evidence of antitumor activity. Exploratory objectives include evaluating changes in plasma metabolites across multiple time points and changes in the stool microbiome pre and post L-glutamine supplementation. If this phase I clinical trial demonstrates the feasibility of L-glutamine in combination with nab-paclitaxel and gemcitabine, we would advance the development of this combination as a first-line systemic option in subjects with metastatic pancreatic cancer, a high-risk subgroup desperately in need of additional therapies.

Glutamine metabolism in breast cancer and possible therapeutic targets

Cancer is characterized by metabolic reprogramming, which is a hot topic in tumor treatment research. Cancer cells alter metabolic pathways to promote their growth, and the common purpose of these altered metabolic pathways is to adapt the metabolic state to the uncontrolled proliferation of cancer cells. Most cancer cells in a state of nonhypoxia will increase the uptake of glucose and produce lactate, called the Warburg effect. Increased glucose consumption is used as a carbon source to support cell proliferation, including nucleotide, lipid and protein synthesis. In the Warburg effect, pyruvate dehydrogenase activity decreases, thereby disrupting the TCA cycle. In addition to glucose, glutamine is also an important nutrient for the growth and proliferation of cancer cells, an important carbon bank and nitrogen bank for the growth and proliferation of cancer cells, providing ribose, nonessential amino acids, citrate, and glycerin necessary for cancer cell growth and proliferation and compensating for the reduction in oxidative phosphorylation pathways in cancer cells caused by the Warburg effect. In human plasma, glutamine is the most abundant amino acid. Normal cells produce glutamine via glutamine synthase (GLS), but the glutamine synthesized by tumor cells is insufficient to meet their high growth needs, resulting in a "glutamine-dependent phenomenon." Most cancers have an increased glutamine demand, including breast cancer. Metabolic reprogramming not only enables tumor cells to maintain the reduction-oxidation (redox) balance and commit resources to biosynthesis but also establishes heterogeneous metabolic phenotypes of tumor cells that are distinct from those of nontumor cells. Thus, targeting the metabolic differences between tumor and nontumor cells may be a promising and novel anticancer strategy. Glutamine metabolic compartments have emerged as promising candidates, especially in TNBC and drug-resistant breast cancer. In this review, the latest discoveries of breast cancer and glutamine metabolism are discussed, novel treatment methods based on amino acid transporters and glutaminase are discussed, and the relationship between glutamine metabolism and breast cancer metastasis, drug resistance, tumor immunity and ferroptosis are explained, which provides new ideas for the clinical treatment of breast cancer.

Radioprotective countermeasures for radiation injury (Review)

A series of physiological and pathological changes occur after radiotherapy and accidental exposure to ionizing radiation (IR). These changes cause serious damage to human tissues and can lead to death. Radioprotective countermeasures are radioprotective agents that prevent and reduce IR injury or have therapeutic effects. Based on a good understanding of radiobiology, a number of protective agents have achieved positive results in early clinical trials. The present review grouped known radioprotective agents according to biochemical categories and potential clinical use, and reviewed radiation countermeasures, i.e., radioprotectors, radiation mitigators and radiotherapeutic agents, with an emphasis on their current status and research progress. The aim of the present review is to facilitate the selection and application of suitable radioprotectors for clinicians and researchers, to prevent or reduce IR injury.

Strategies to Mitigate Chemotherapy and Radiation Toxicities That Affect Eating

Background: Cancer and its therapy is commonly associated with a variety of side effects that impact eating behaviors that reduce nutritional intake. This review will outline potential causes of chemotherapy and radiation damage as well as approaches for the amelioration of the side effects of cancer during therapy. Methods: Information for clinicians, patients, and their caregivers about toxicity mitigation including nausea reduction, damage to epithelial structures such as skin and mucosa, organ toxicity, and education is reviewed. Results: How to anticipate, reduce, and prevent some toxicities encountered during chemotherapy and radiation is detailed with the goal to improve eating behaviors. Strategies for health care professionals, caregivers, and patients to consider include (a) the reduction in nausea and vomiting, (b) decreasing damage to the mucosa, (c) avoiding a catabolic state and muscle wasting (sarcopenia), and (d) developing therapeutic alliances with patients, caregivers, and oncologists. Conclusions: Although the reduction of side effects involves anticipatory guidance and proactive team effort (e.g., forward observation, electronic interactions, patient reported outcomes), toxicity reduction can be satisfying for not only the patient, but everyone involved in cancer care.

A systematic review of home-based dietary interventions during radiation therapy for cancer

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This is the first systematic review of dietary recommendations for patients receiving radiation therapy.

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High fiber diet may improve diarrhea in pelvic cancer patients.

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Limited data to support safe and efficacious use of dietary interventions during radiotherapy.

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No dietary intervention has been shown to improve survival.

Purpose

Our objectives are to assess (1) the acceptability and feasibility of dietary interventions for patients undergoing radiation therapy (RT), and (2) the impact of dietary interventions on patient reported outcomes, toxicities, and survival.

Methods

A PICOS/PRISMA/MOOSE selection protocol was used to include articles that evaluate adding dietary interventions to patients receiving RT. Acceptability was defined as (# accepting/# approached); feasibility was (# completing/# approached). Patient-reported outcomes were reported based on questionnaires used in each study and survival was measured from the date of diagnosis until death in each study. Level of evidence was assessed with Center for Evidence-Based Medicine (CEBM) criteria.

Results

Sixteen articles were included; among these, 2027 patients were approached regarding the intervention, and 1661 accepted (81.9%); of these, 1543 (92.9%) completed the prescribed diet + RT course. The most common cancers included were gynecological, head and neck, and gastrointestinal. For patients with pelvic cancers, a high fiber diet may improve diarrhea (CEBM level 1b). Enteral nutrition formula, including formulas with proteins such as L-arginine, lipids such as eicosapentaenoic acids, glucids, and ribonucleotides, may help prevent of malnutrition in head and neck cancer patients undergoing RT (level 2b). Vitamin C and β-carotene may reduce of xerostomia in head and neck cancer patients; however, the studies evaluating these vitamins included vitamin E, which increases all-cause mortality (level 2b). No dietary intervention for cancer patients receiving RT has been shown to improve survival.

Conclusion

There are limited data to support safe and efficacious use of dietary interventions during RT.

Glutamine for Amelioration of Radiation and Chemotherapy Associated Mucositis during Cancer Therapy

Glutamine is a major dietary amino acid that is both a fuel and nitrogen donor for healing tissues damaged by chemotherapy and radiation. Evidence supports the benefit of oral (enteral) glutamine to reduce symptoms and improve and/or maintain quality of life of cancer patients. Benefits include not only better nutrition, but also decreased mucosal damage (mucositis, stomatitis, pharyngitis, esophagitis, and enteritis). Glutamine supplementation in a high protein diet (10 grams/day) + disaccharides, such as sucrose and/or trehalose, is a combination that increases glutamine uptake by mucosal cells. This increased topical effect can reduce painful mucosal symptoms and ulceration associated with chemotherapy and radiation in the head and neck region, esophagus, stomach and small intestine. Topical and oral glutamine seem to be the preferred routes for this amino acid to promote mucosal healing during and after cancer treatment.

Major surgery diminishes systemic arginine availability and suppresses nitric oxide response to feeding in patients with early stage breast cancer

BACKGROUND & AIMS

Plasma arginine (ARG) levels are reduced in breast cancer, suggesting diminished systemic ARG availability. ARG and its product nitric oxide (NO) are important in early postoperative recovery due to its roles in immune function and wound healing. It remains unclear whether major surgery further diminishes systemic ARG availability due to enhanced ARG catabolism and/or insufficient endogenous ARG synthesis negatively affecting NO synthesis in patients with early stage breast cancer.

METHODS

In 9 women with early stage breast malignancy and 9 healthy women with genetic predisposition to breast cancer, whole body ARG and citrulline (CIT) rates of appearances were measured to determine their production rates prior to and within 24 h after major breast surgery by stable isotope methodology in the postabsorptive and postprandial state. The conversions of CIT > ARG, ARG > CIT, and ARG > Urea (markers of de novo ARG and NO synthesis, arginase activity, respectively), and ARG clearance (reflecting ARG disposal capacity) were calculated.

RESULTS

Prior to surgery, plasma ARG, CIT and glutamine concentrations were lower in cancer (P < 0.05) but no differences were found in the rate of appearances of ARG, CIT and their conversions. Surgery increased ARG clearance and reduced CIT rate of appearance, conversion of CIT > ARG (P < 0.001), and plasma ARG, CIT, ornithine concentrations (P < 0.001). Furthermore, postprandial increase in ARG > CIT conversion (P < 0.05), plasma ARG (P < 0.001) and CIT (P = 0.06) concentrations were lower after surgery. The cancer group had lower values for postprandial increase in ARG > CIT conversion, plasma CIT (P < 0.05) and glutamine concentrations (P = 0.08).

CONCLUSIONS

Major surgery in early stage breast cancer further reduces systemic ARG availability in the early phase of recovery due to a combined process of increased ARG catabolism and impaired endogenous ARG synthesis. The suppressed postprandial NO increase in early stage cancer suggests that specific nutritional approaches are advised to increase ARG availability after major surgery although the effects on postoperative recovery remain unclear. This trial was registered at clinicaltrials.gov as NCT00497380.

Clinical practice guidelines on the evidence-based use of integrative therapies during and after breast cancer treatment

Answer questions and earn CME/CNE Patients with breast cancer commonly use complementary and integrative therapies as supportive care during cancer treatment and to manage treatment-related side effects. However, evidence supporting the use of such therapies in the oncology setting is limited. This report provides updated clinical practice guidelines from the Society for Integrative Oncology on the use of integrative therapies for specific clinical indications during and after breast cancer treatment, including anxiety/stress, depression/mood disorders, fatigue, quality of life/physical functioning, chemotherapy-induced nausea and vomiting, lymphedema, chemotherapy-induced peripheral neuropathy, pain, and sleep disturbance. Clinical practice guidelines are based on a systematic literature review from 1990 through 2015. Music therapy, meditation, stress management, and yoga are recommended for anxiety/stress reduction. Meditation, relaxation, yoga, massage, and music therapy are recommended for depression/mood disorders. Meditation and yoga are recommended to improve quality of life. Acupressure and acupuncture are recommended for reducing chemotherapy-induced nausea and vomiting. Acetyl-L-carnitine is not recommended to prevent chemotherapy-induced peripheral neuropathy due to a possibility of harm. No strong evidence supports the use of ingested dietary supplements to manage breast cancer treatment-related side effects. In summary, there is a growing body of evidence supporting the use of integrative therapies, especially mind-body therapies, as effective supportive care strategies during breast cancer treatment. Many integrative practices, however, remain understudied, with insufficient evidence to be definitively recommended or avoided. CA Cancer J Clin 2017;67:194-232. © 2017 American Cancer Society.

Immune Therapy for Sarcomas

Absolute lymphocyte count (ALC) recovery rapidly occurring at 14 days after start of chemotherapy for osteosarcoma and Ewing sarcoma is a good prognostic factor. Conversely, lymphopenia is associated with significantly decreased sarcoma survival. Clearly, the immune system can contribute towards better survival from sarcoma. This chapter will describe treatment and host factors that influence immune function and how effective local control and systemic interventions of sarcoma therapy can cause inflammation and/or immune suppression but are currently the standard of care. Preclinical and clinical efforts to enhance immune function against sarcoma will be reviewed. Interventions to enhance immune function against sarcoma have included regional therapy (surgery, cryoablation, radiofrequency ablation, electroporation, and radiotherapy), cytokines, macrophage activators (mifamurtide), vaccines, natural killer (NK) cells, T cell receptor (TCR) and chimeric antigen receptor (CAR) T cells, and efforts to decrease inflammation. The latter is particularly important because of new knowledge about factors influencing expression of checkpoint inhibitory molecules, PD1 and CTLA-4, in the tumor microenvironment. Since these molecules can now be blocked using anti-PD1 and anti-CTLA-4 antibodies, how to translate this knowledge into more effective immune therapies in the future as well as how to augment effectiveness of current interventions (e.g., radiotherapy) is a challenge. Barriers to implementing this knowledge include cost of agents that release immune checkpoint blockade and coordination of cost-effective outpatient sarcoma treatment. Information on how to research clinical trial eligibility criteria and how to access current immune therapy trials against sarcoma are shared, too.

From Krebs to clinic: glutamine metabolism to cancer therapy

The resurgence of research into cancer metabolism has recently broadened interests beyond glucose and the Warburg effect to other nutrients, including glutamine. Because oncogenic alterations of metabolism render cancer cells addicted to nutrients, pathways involved in glycolysis or glutaminolysis could be exploited for therapeutic purposes. In this Review, we provide an updated overview of glutamine metabolism and its involvement in tumorigenesis in vitro and in vivo, and explore the recent potential applications of basic science discoveries in the clinical setting.

The impact of glutamine supplementation on the symptoms of ataxia-telangiectasia: a preclinical assessment

BACKGROUND

Our previous studies of Alzheimer's disease (AD) suggested that glutamine broadly improves cellular readiness to respond to stress and acts as a neuroprotectant both in vitro and in AD mouse models. We now expand our studies to a second neurodegenerative disease, ataxia-telangiectasia (A-T). Unlike AD, where clinically significant cognitive decline does not typically occur before age 65, A-T symptoms appear in early childhood and are caused exclusively by mutations in the ATM (A-T mutated) gene.

RESULTS

Genetically ATM-deficient mice and wild type littermates were maintained with or without 4 % glutamine in their drinking water for several weeks. In ATM mutants, glutamine supplementation restored serum glutamine and glucose levels and reduced body weight loss. Lost neurophysiological function assessed through the magnitude of hippocampal long term potentiation was significantly restored. Glutamine supplemented mice also showed reduced thymus pathology and, remarkably, a full one-third extension of lifespan. In vitro assays revealed that ATM-deficient cells are more sensitive to glutamine deprivation, while supra-molar glutamine (8 mM) partially rescued the reduction of BDNF expression and HDAC4 nuclear translocation of genetically mutant Atm(-/-) neurons. Analysis of microarray data suggested that glutamine metabolism is significantly altered in human A-T brains as well.

CONCLUSION

Glutamine is a powerful part of an organism's internal environment. Changes in its concentrations can have a huge impact on the function of all organ systems, especially the brain. Glutamine supplementation thus bears consideration as a therapeutic strategy for the treatment of human A-T and perhaps other neurodegenerative diseases.

ESPEN guidelines on nutrition in cancer patients

Cancers are among the leading causes of morbidity and mortality worldwide, and the number of new cases is expected to rise significantly over the next decades. At the same time, all types of cancer treatment, such as surgery, radiation therapy, and pharmacological therapies are improving in sophistication, precision and in the power to target specific characteristics of individual cancers. Thus, while many cancers may still not be cured they may be converted to chronic diseases. All of these treatments, however, are impeded or precluded by the frequent development of malnutrition and metabolic derangements in cancer patients, induced by the tumor or by its treatment. These evidence-based guidelines were developed to translate current best evidence and expert opinion into recommendations for multi-disciplinary teams responsible for identification, prevention, and treatment of reversible elements of malnutrition in adult cancer patients. The guidelines were commissioned and financially supported by ESPEN and by the European Partnership for Action Against Cancer (EPAAC), an EU level initiative. Members of the guideline group were selected by ESPEN to include a range of professions and fields of expertise. We searched for meta-analyses, systematic reviews and comparative studies based on clinical questions according to the PICO format. The evidence was evaluated and merged to develop clinical recommendations using the GRADE method. Due to the deficits in the available evidence, relevant still open questions were listed and should be addressed by future studies. Malnutrition and a loss of muscle mass are frequent in cancer patients and have a negative effect on clinical outcome. They may be driven by inadequate food intake, decreased physical activity and catabolic metabolic derangements. To screen for, prevent, assess in detail, monitor and treat malnutrition standard operating procedures, responsibilities and a quality control process should be established at each institution involved in treating cancer patients. All cancer patients should be screened regularly for the risk or the presence of malnutrition. In all patients - with the exception of end of life care - energy and substrate requirements should be met by offering in a step-wise manner nutritional interventions from counseling to parenteral nutrition. However, benefits and risks of nutritional interventions have to be balanced with special consideration in patients with advanced disease. Nutritional care should always be accompanied by exercise training. To counter malnutrition in patients with advanced cancer there are few pharmacological agents and pharmaconutrients with only limited effects. Cancer survivors should engage in regular physical activity and adopt a prudent diet.

Is glutamine deficiency the link between inflammation, malnutrition, and fatigue in cancer patients?

PURPOSE

Evaluation of potential associations between plasma glutamine levels and the incidence of cancer related fatigue, physical performance, poor nutritional status, and inflammation in patients with solid tumors.

STUDY DESIGN

Mono-center cross-sectional study recruiting 100 (34 women) consecutive patients (September 2009-March 2011; ≥18 y) with solid tumors and causal tumor therapy.

METHODOLOGY

Fasting venous blood was harvested for routine clinical chemistry, amino acid (HPLC) and inflammation marker analyses. Clinical assessments included global, physical, affective and cognitive fatigue (questionnaire) and Karnofsky performance status. Nutritional status was evaluated using bioelectrical impedance analysis, the Prognostic Inflammatory and Nutritional Index and plasma protein levels. Regression analyses were performed to correlate continuous variables with plasma glutamine (95% confidence intervals).

RESULTS

Nutritional status was impaired in 19% of the patients. Average plasma glutamine concentration (574.0 ± 189.6 μmol/L) was within normal range but decreased with impaired physical function. Plasma glutamine was linked to the ratio extracellular to body cell mass (p < 0.044), CRP (p < 0.001), physical (p = 0.014), affective (p = 0.041), and global fatigue (p = 0.030). Markers of inflammation increased with low physical performance.

CONCLUSIONS

The data support our working hypothesis that in cancer patients systemic inflammation maintains a catabolic situation leading to malnutrition symptoms and glutamine deprivation, the latter being associated with cancer related fatigue.