Methodological quality of research on perioperative immunomodulatory supplementation in oncological gastrointestinal tract surgery: a meta-research protocol.

INTRODUCTION: One of the topics that show differences of opinion in the scientific field of nutrition is the recommendation by clinical practice guidelines (CPGs) of an immunomodulatory diet with arginine, nucleotides and omega-3 for individuals diagnosed with cancer undergoing major surgery. The quality of the recommendations is directly related to credibility, transparency and rigour in their development, but also to the quality of the studies published and available for inclusion in the recommendation, such as systematic reviews (SRs) and randomised clinical trials. The aim of this study is to evaluate the methodological quality of the recommendation of perioperative immunomodulatory supplementation for individuals with gastrointestinal and head and neck cancer, the CPGs, and the studies that support the recommendations. METHODS AND ANALYSIS: We will conduct a systematic search for CPGs. Recommendations for nutritional supplementation with immunomodulatory substrates for individuals undergoing major oncological surgery will be analysed using the Appraisal of Guidelines Research and Evaluation-Recommendations Excellence tool. CPGs will be analysed using the Appraisal of Guidelines Research and Evaluation II tool. The SRs cited in the recommendations will be analysed using the A Measurement Tool to Assess Systematic Reviews II tool and additional questions regarding heterogeneity in reviews. The clinical trials cited in the SRs and in the guideline recommendations (when applicable) will be analysed according to questions regarding heterogeneity in trials. The results will be presented in tables or charts using descriptive analyses. ETHICS AND DISSEMINATION: The results of this study will be disseminated through relevant conferences and peer-reviewed journals. PROTOCOL REGISTRATION NUMBER: 10.17605/OSF.IO/X2GYT.

L-arginine mitigates bleomycin-induced pulmonary fibrosis in rats through regulation of HO-1/PPAR-γ/ß-catenin axis.

Pulmonary fibrosis is a chronic and progressively deteriorating lung condition that can be replicated in laboratory animals by administering bleomycin, a chemotherapeutic antibiotic known for its lung fibrosis-inducing side effects. L-arginine, a semi-essential amino acid, is recognized for its diverse biological functions, including its potential to counteract fibrosis. This study aimed to evaluate the antifibrotic properties of L-arginine on bleomycin-induced pulmonary fibrosis in rats. The administration of a single intratracheal dose of bleomycin resulted in visible and microscopic damage to lung tissues, an uptick in oxidative stress markers, and an elevation in inflammatory, apoptotic, and fibrotic indicators. A seven-day treatment with L-arginine post-bleomycin exposure markedly improved the gross and histological architecture of the lungs, prevented the rise of malondialdehyde and carbonyl content, and enhanced total antioxidant capacity alongside the activities of antioxidant enzymes. Also, L-arginine attenuated the expression of the pro-fibrotic factors, transforming growth factor-ß and lactate dehydrogenase in bronchoalveolar lavage fluid. In the lung tissue, L-arginine reduced collagen deposition, hydroxyproline concentration, and mucus production, along with decreasing expression of α-smooth muscle actin, tumor necrosis factor-α, caspase-3, matrix metalloproteinase-9, and ß-catenin. Moreover, it boosted levels of nitric oxide and upregulated the expression of peroxisome proliferator-activated receptor-γ (PPAR-γ), heme oxygenase-1 (HO-1), and E-cadherin and downregulating the expression of ß-catenin. These findings suggest that L-arginine has preventive activities against bleomycin-induced pulmonary fibrosis. This effect can be attributed to the increased production of nitric oxide, which modulates the HO-1/PPAR-γ/ß-catenin axis.

Arginine-Nanoenzyme with Timely Angiogenesis for Promoting Diabetic Wound Healing.

The successful treatment of diabetic wounds requires strategies that promote anti-inflammation, angiogenesis, and re-epithelialization of the wound. Excessive oxidative stress in diabetic ulcers (DUs) inhibits cell proliferation and hinders timely vascular formation and macrophage polarization from pro-inflammatory M1 to anti-inflammatory M2, resulting in a persistent inflammatory environment and a nonhealing wound. We designed arginine-nanoenzyme (FTA) with mimic-catalase and arginine-loading. 2,3,4-trihydroxy benzaldehyde and arginine (Arg) were connected by a Schiff base bond, and the nanoassembly of Arg to FTA was driven by the coordination force between a ferric ion and polyphenol and noncovalent bond force such as a hydrogen bond. FTA could remove excess reactive oxygen species at the wound site in situ and convert it to oxygen to improve hypoxia. Meanwhile, Arg was released and catalytically metabolized by NO synthase in M1 to promote vascular repair in the early phase. In the late phase, the metabolite of Arg catalyzed by arginase in M2 was mainly ornithine, which played a vital role in promoting tissue repair, which implemented angiogenesis timely and prevented hypertrophic scars. Mechanistically, FTA activated the cAMP signaling pathway combined with reducing inflammation and ameliorating angiogenesis, which resulted in excellent therapeutic effects on a DU mice model.

Pegargiminase Plus First-Line Chemotherapy in Patients With Nonepithelioid Pleural Mesothelioma: The ATOMIC-Meso Randomized Clinical Trial.

Importance: Arginine deprivation using ADI-PEG20 (pegargiminase) combined with chemotherapy is untested in a randomized study among patients with cancer. ATOMIC-Meso (ADI-PEG20 Targeting of Malignancies Induces Cytotoxicity-Mesothelioma) is a pivotal trial comparing standard first-line chemotherapy plus pegargiminase or placebo in patients with nonepithelioid pleural mesothelioma. Objective: To determine the effect of pegargiminase-based chemotherapy on survival in nonepithelioid pleural mesothelioma, an arginine-auxotrophic tumor. Design, Setting, and Participants: This was a phase 2-3, double-blind randomized clinical trial conducted at 43 centers in 5 countries that included patients with chemotherapy-naive nonepithelioid pleural mesothelioma from August 1, 2017, to August 15, 2021, with at least 12 months' follow-up. Final follow-up was on August 15, 2022. Data analysis was performed from March 2018 to June 2023. Intervention: Patients were randomly assigned (1:1) to receive weekly intramuscular pegargiminase (36.8 mg/m2) or placebo. All patients received intravenous pemetrexed (500 mg/m2) and platinum (75-mg/m2 cisplatin or carboplatin area under the curve 5) chemotherapy every 3 weeks up to 6 cycles. Pegargiminase or placebo was continued until progression, toxicity, or 24 months. Main Outcomes and Measures: The primary end point was overall survival, and secondary end points were progression-free survival and safety. Response rate by blinded independent central review was assessed in the phase 2 portion only. Results: Among 249 randomized patients (mean [SD] age, 69.5 [7.9] years; 43 female individuals [17.3%] and 206 male individuals [82.7%]), all were included in the analysis. The median overall survival was 9.3 months (95% CI, 7.9-11.8 months) with pegargiminase-chemotherapy as compared with 7.7 months (95% CI, 6.1-9.5 months) with placebo-chemotherapy (hazard ratio [HR] for death, 0.71; 95% CI, 0.55-0.93; P = .02). The median progression-free survival was 6.2 months (95% CI, 5.8-7.4 months) with pegargiminase-chemotherapy as compared with 5.6 months (95% CI, 4.1-5.9 months) with placebo-chemotherapy (HR, 0.65; 95% CI, 0.46-0.90; P = .02). Grade 3 to 4 adverse events with pegargiminase occurred in 36 patients (28.8%) and with placebo in 21 patients (16.9%); drug hypersensitivity and skin reactions occurred in the experimental arm in 3 patients (2.4%) and 2 patients (1.6%), respectively, and none in the placebo arm. Rates of poststudy treatments were comparable in both arms (57 patients [45.6%] with pegargiminase vs 58 patients [46.8%] with placebo). Conclusions and Relevance: In this randomized clinical trial of arginine depletion with pegargiminase plus chemotherapy, survival was extended beyond standard chemotherapy with a favorable safety profile in patients with nonepithelioid pleural mesothelioma. Pegargiminase-based chemotherapy as a novel antimetabolite strategy for mesothelioma validates wider clinical testing in oncology. Trial Registration: ClinicalTrials.gov Identifier: NCT02709512.

Modulatory effects of supplementation of Lentinula edodes mycelia extract and l-arginine on the therapeutic efficacy of immunogenic chemotherapy in colon cancer-bearing mice.

Some chemotherapeutic drugs can induce cancer cell death and enhance antitumor T-cell immunity in cancer-bearing hosts. Immunomodulatory reagents could augment such chemotherapy-induced effects. We previously reported that oral digestion of Lentinula edodes mycelia (L.E.M.) extract or  l-arginine supplementation can augment antitumor T-cell responses in cancer-bearing mice. In this study, the effects of L.E.M. extract with or without  l-arginine on the therapeutic efficacy of immunogenic chemotherapy by 5-fluorouracil (5-FU)/oxaliplatin (L-OHP) and/or cyclophosphamide (CP) are examined using two mouse colon cancer models. In MC38 and CT26 cancer models, therapy with 5-FU/L-OHP/CP significantly suppressed tumor growth, and supplementation with L.E.M. extract halved the tumor volumes. However, the modulatory effect of L.E.M. extract was not significant. In the CT26 cancer model, supplementation with L.E.M. extract and  l-arginine had no clear effect on tumor growth. In contrast, their addition to chemotherapy halved the tumor volumes, although the effect was not significant. There was no difference in the cytotoxicity of tumor-specific cytotoxic T cells generated from CT26-cured mice treated by chemotherapy alone versus chemotherapy combined with L.E.M. extract/ l-arginine. These results indicate that the antitumor effects of immunogenic chemotherapy were too strong to ascertain the effects of supplementation of L.E.M. extract and  l-arginine, but these reagents nonetheless have immunomodulatory effects on the therapeutic efficacy of immunogenic chemotherapy in colon cancer-bearing mice.

Promising role of protein arginine methyltransferases in overcoming anti-cancer drug resistance.

Drug resistance remains a major challenge in cancer treatment, necessitating the development of novel strategies to overcome it. Protein arginine methyltransferases (PRMTs) are enzymes responsible for epigenetic arginine methylation, which regulates various biological and pathological processes, as a result, they are attractive therapeutic targets for overcoming anti-cancer drug resistance. The ongoing development of small molecules targeting PRMTs has resulted in the generation of chemical probes for modulating most PRMTs and facilitated clinical treatment for the most advanced oncology targets, including PRMT1 and PRMT5. In this review, we summarize various mechanisms underlying protein arginine methylation and the roles of specific PRMTs in driving cancer drug resistance. Furthermore, we highlight the potential clinical implications of PRMT inhibitors in decreasing cancer drug resistance. PRMTs promote the formation and maintenance of drug-tolerant cells via several mechanisms, including altered drug efflux transporters, autophagy, DNA damage repair, cancer stem cell-related function, epithelial-mesenchymal transition, and disordered tumor microenvironment. Multiple preclinical and ongoing clinical trials have demonstrated that PRMT inhibitors, particularly PRMT5 inhibitors, can sensitize cancer cells to various anti-cancer drugs, including chemotherapeutic, targeted therapeutic, and immunotherapeutic agents. Combining PRMT inhibitors with existing anti-cancer strategies will be a promising approach for overcoming anti-cancer drug resistance. Furthermore, enhanced knowledge of the complex functions of arginine methylation and PRMTs in drug resistance will guide the future development of PRMT inhibitors and may help identify new clinical indications.

Joint analysis of the metabolomics and transcriptomics uncovers the dysregulated network and develops the diagnostic model of high-risk neuroblastoma.

High-risk neuroblastoma (HR-NB) has a significantly lower survival rate compared to low- and intermediate-risk NB (LIR-NB) due to the lack of risk classification diagnostic models and effective therapeutic targets. The present study aims to characterize the differences between neuroblastomas with different risks through transcriptomic and metabolomic, and establish an early diagnostic model for risk classification of neuroblastoma.Plasma samples from 58 HR-NB and 38 LIR-NB patients were used for metabolomics analysis. Meanwhile, NB tissue samples from 32 HR-NB and 23 LIR-NB patients were used for transcriptomics analysis. In particular, integrative metabolomics and transcriptomic analysis was performed between HR-NB and LIR-NB. A total of 44 metabolites (P < 0.05 and fold change > 1.5) were altered, including 12 that increased and 32 that decreased in HR-NB. A total of 1,408 mRNAs (P < 0.05 and |log2(fold change)|> 1) showed significantly altered in HR-NB, of which 1,116 were upregulated and 292 were downregulated. Joint analysis of both omic data identified 4 aberrant pathways (P < 0.05 and impact ≥ 0.5) consisting of glycerolipid metabolism, retinol metabolism, arginine biosynthesis and linoleic acid metabolism. Importantly, a HR-NB risk classification diagnostic model was developed using plasma circulating-free S100A9, CDK2, and UNC5D, with an area under receiver operating characteristic curve of 0.837 where the sensitivity and specificity in the validation set were both 80.0%. This study presents a novel pioneering study demonstrating the metabolomics and transcriptomics profiles of HR-NB. The glycerolipid metabolism, retinol metabolism, arginine biosynthesis and linoleic acid metabolism were altered in HR-NB. The risk classification diagnostic model based on S100A9, CDK2, and UNC5D can be clinically used for HR-NB risk classification.

Untargeted and Targeted Metabolomics Reveal the Active Peptide of Eupolyphaga sinensis Walker against Hyperlipidemia by Modulating Imbalance in Amino Acid Metabolism.

The active peptide (APE) of Eupolyphaga sinensis Walker, which is prepared by bioenzymatic digestion, has significant antihyperlipidemic effects in vivo, but its mechanism of action on hyperlipidemia is not clear. Recent studies on amino acid metabolism suggested a possible link between it and hyperlipidemia. In this study, we first characterized the composition of APE using various methods. Then, the therapeutic effects of APE on hyperlipidemic rats were evaluated, including lipid levels, the inflammatory response, and oxidative stress. Finally, the metabolism-regulating mechanisms of APE on hyperlipidemic rats were analyzed using untargeted and targeted metabolomic approaches. The results showed that APE significantly reduced the accumulation of fat, oxidative stress levels, and serum pro-inflammatory cytokine levels. Untargeted metabolomic analysis showed that the mechanism of the hypolipidemic effect of APE was mainly related to tryptophan metabolism, phenylalanine metabolism, arginine biosynthesis, and purine metabolism. Amino-acid-targeted metabolomic analysis showed that significant differences in the levels of eight amino acids occurred after APE treatment. Among them, the expression of tryptophan, alanine, glutamate, threonine, valine, and phenylalanine was upregulated, and that of arginine and proline was downregulated in APE-treated rats. In addition, APE significantly downregulated the mRNA expression of SREBP-1, SREBP-2, and HMGCR. Taking these points together, we hypothesize that APE ameliorates hyperlipidemia by modulating amino acid metabolism in the metabolome of the serum and feces, mediating the SREBP/HMGCR signaling pathway, and reducing oxidative stress and inflammation levels.

Determining effects of nitrate, arginine, and ferrous on antibiotic recalcitrance of clinical strains of Pseudomonas aeruginosa in biofilm-inspired alginate encapsulates.

BACKGROUND: Biofilms play a role in recalcitrance and treatability of bacterial infections, but majority of known antibiotic resistance mechanisms are biofilm-independent. Biofilms of Pseudomonas aeruginosa, especially in cystic fibrosis patients infected with the alginate producing strains in their lungs, are hard to treat. Changes in growth-related bacterial metabolism in biofilm affect their antibiotic recalcitrance which could be considered for new therapies designed based on these changes. In this study, effects of nitrate, arginine, and ferrous were investigated on antibiotic recalcitrance in alginate-encapsulated P. aeruginosa strains isolated from cystic fibrosis patients in the presence of amikacin, tobramycin, and ciprofloxacin. Also, expression of an efflux pump gene, mexY, was analyzed in selected strains in the presence of amikacin and ferrous. METHODS: Clinical P. aeruginosa strains were isolated from cystic fibrosis patients and minimum inhibitory concentration of amikacin, tobramycin, and ciprofloxacin was determined against all the strains. For each antibiotic, a susceptible and a resistant or an intermediate-resistant strain were selected, encapsulated into alginate beads, and subjected to minimal biofilm eradication concentration (MBEC) test. After determining MBECs, sub-MBEC concentrations (antibiotics at concentrations one level below the determined MBEC) for each antibiotic were selected and used to study the effects of nitrate, arginine, and ferrous on antibiotic recalcitrance of encapsulated strains. Effects of ferrous and amikacin on expression of the efflux pump gene, mexY, was studied on amikacin sensitive and intermediate-resistant strains. One-way ANOVA and t test were used as the statistical tests. RESULTS: According to the results, the supplements had a dose-related effect on decreasing the number of viable cells; maximal effect was noted with ferrous, as ferrous supplementation significantly increased biofilm susceptibility to both ciprofloxacin and amikacin in all strains, and to tobramycin in a resistant strain. Also, treating an amikacin-intermediate strain with amikacin increased the expression of mexY gene, which has a role in P. aeruginosa antibiotic recalcitrance, while treating the same strain with ferrous and amikacin significantly decreased the expression of mexY gene, which was a promising result. CONCLUSIONS: Our results support the possibility of using ferrous and arginine as an adjuvant to enhance the efficacy of conventional antimicrobial therapy of P. aeruginosa infections.

Comparative Effects of Different Nutritional Supplements on Inflammation, Nutritional Status, and Clinical Outcomes in Colorectal Cancer Patients: A Systematic Review and Network Meta-Analysis.

Nutritional supplements have been widely used in colorectal cancer (CRC) patients. The aim of this network meta-analysis (NMA) was to compare the effects of different nutritional supplements on inflammation, nutritional status, and clinical outcomes in CRC patients. Four electronic databases were searched until December 2022. Randomized controlled trials (RCTs) comparing nutritional supplements of omega-3 fatty acids (omega-3), arginine, vitamin D, glutamine, probiotics, or their combinations with placebo or standard treatment were selected. The outcomes were inflammatory indicators, nutritional indicators, and clinical outcomes. A random-effects Bayesian NMA was performed to rank the effect of each supplement. In total, 34 studies involving 2841 participants were included. Glutamine was superior in decreasing tumor necrosis factor-α (MD -25.2; 95% CrI [-32.62, -17.95]), whereas combined omega-3 and arginine supplementation was more effective in decreasing interleukin-6 (MD -61.41; 95% CrI [-97.85, -24.85]). No nutritional supplements significantly maintained nutritional indicators in CRC patients. Regarding clinical outcomes, glutamine ranked highest in reducing the length of hospital stay (MD -3.71; 95% CrI [-5.89, -1.72]) and the incidence of wound infections (RR 0.12; 95% CrI [0, 0.85]), and probiotics were rated as best in reducing the incidence of pneumonia (RR 0.38; 95% CrI [0.15, 0.81]). Future well-designed RCTs are needed to further confirm these findings.

Clinical study on the efficacy and tolerability of an oral supplement based on arginine, l-cystine, zinc and B6 vitamin (Cystiphane®) in patients with telogen effluvium.

BACKGROUND: Telogen effluvium (TE) is a common cause of non-cicatricial hair loss with no treatment-standardized protocol. The aim of our study was to evaluate the efficacy, tolerability, and patient compliance of a treatment with an oral supplement based on arginine, l-cystine, zinc and B6 vitamin (Cystiphane®, Laboratoires Bailleul, Geneva, Switzerland) with hair-growth properties, administered 4 times daily, in patients affected by TE. METHODS: We recruited 20 patients, aged between 18 and 70 years old, affected by TE. Patients were asked to take the oral supplement as a monotherapy, four tablets daily, in one or two administrations during meals. The study lasted 3 months. We evaluated the efficacy and tolerability of the treatment both qualitatively by collecting the clinician's opinion through a clinical evaluation and clinical-anamnestic form filled in by the researcher, and quantitatively through global photography and trichoscopy. We collected the patient's opinion through a self-assessment test, at the beginning of the recruitment and after 3 months of treatment. RESULTS: Eighteen patients were evaluated. After 3 months of taking the supplement, the researcher rated an average improvement of 2.89 at the clinical evaluation. For what concerns hair quantity, at the control trichoscopy, the mean trichoscopic value had risen to +2.055, whereas for hair diameter the mean trichoscopic diameter value had increased to +1.83. After 3 months of treatment, patients gave an average efficacy opinion of 3.61. CONCLUSIONS: The oral supplement has proved effective as an adjuvant in the treatment of TE in our cohort of patients.

Targeting epigenetic features in clear cell sarcomas based on patient-derived cell lines.

BACKGROUND: Clear cell sarcomas (CCSs) are translocated aggressive malignancies, most commonly affecting young adults with a high incidence of metastases and a poor prognosis. Research into the disease is more feasible when adequate models are available. By establishing CCS cell lines from a primary and metastatic lesion and isolating healthy fibroblasts from the same patient, the in vivo process is accurately reflected and aspects of clinical multistep carcinogenesis recapitulated. METHODS: Isolated tumor cells and normal healthy skin fibroblasts from the same patient were compared in terms of growth behavior and morphological characteristics using light and electron microscopy. Tumorigenicity potential was determined by soft agar colony formation assay and in vivo xenograft applications. While genetic differences between the two lineages were examined by copy number alternation profiles, nuclear magnetic resonance spectroscopy determined arginine methylation as epigenetic features. Potential anti-tumor effects of a protein arginine N-methyltransferase type I (PRMT1) inhibitor were elicited in 2D and 3D cell culture experiments using cell viability and apoptosis assays. Statistical significance was calculated by one-way ANOVA and unpaired t-test. RESULTS: The two established CCS cell lines named MUG Lucifer prim and MUG Lucifer met showed differences in morphology, genetic and epigenetic data, reflecting the respective original tissue. The detailed cell line characterization especially in regards to the epigenetic domain allows investigation of new innovative therapies. Based on the epigenetic data, a PRMT1 inhibitor was used to demonstrate the targeted antitumor effect; normal tissue cells isolated and immortalized from the same patient were not affected with the IC50 used. CONCLUSIONS: MUG Lucifer prim, MUG Lucifer met and isolated and immortalized fibroblasts from the same patient represent an ideal in vitro model to explore the biology of CCS. Based on this cell culture model, novel therapies could be tested in the form of PRMT1 inhibitors, which drive tumor cells into apoptosis, but show no effect on fibroblasts, further supporting their potential as promising treatment options in the combat against CCS. The data substantiate the importance of tailored therapies in the advanced metastatic stage of CCS.

Pharmacokinetics of L-Citrulline in Neonates at Risk of Developing Bronchopulmonary Dysplasia-Associated Pulmonary Hypertension.

BACKGROUND: Options to treat pulmonary hypertension (PH) in neonates with bronchopulmonary dysplasia (BPD) are few and largely ineffective. Improving the bioavailability of nitric oxide (NO) might be an efficacious treatment for BPD-PH. When administered orally, the NO-L-arginine precursor, L-citrulline, increases NO production in children and adults, however, pharmacokinetic (PK) studies of oral L-citrulline have not been performed in infants and children. OBJECTIVES: This study characterized the PK of enterally administered L-citrulline in neonates at risk of developing BPD-PH to devise a model-informed dosing strategy. METHODS AND RESULTS: Ten premature neonates (≤ 28 weeks gestation) were administered a single dose of 150 mg/kg (powder form solubilized in sterile water) oral L-citrulline at 32 ± 1 weeks postmenstrual age. Due to the need to limit blood draws, time windows were used to maximize the sampling over the dosing interval by assigning neonates to one of two groups (ii) samples collected pre-dose and at 1- and 2.5-h post-dose, and (ii) pre-dose and 0.25- and 3-h post-dose. The L-arginine concentrations (µmol/L) and the L-citrulline (µmol/L) plasma concentration-time data were evaluated using non-compartmental analysis (Phoenix WinNonlin version 8.1). Optimal dosage strategies were derived using a simulation-based methodology. Simulated doses of 51.5 mg or 37.5 mg/kg given four times a day produced steady-state concentrations close to a target of 50 µmol/L. The volume of distribution (V/F) and clearance (CL/F) were 302.89 ml and 774.96 ml/h, respectively, with the drug exhibiting a half-life of 16 minutes. The AUC from the time of dosing to the time of last concentration was 1473.3 h*µmol/L, with Cmax and Tmax of 799 µmol/L and 1.55 h, respectively. CONCLUSION: This is the first PK study in neonates presenting data that can be used to inform dosing strategies in future randomized controlled trials evaluating enteral L-citrulline as a potential treatment to reduce PH associated with BPD in premature neonates. REGISTRATION: Clinical trials.gov Identifier: NCT03542812.

A modulatory effect of L-arginine supplementation on anticancer effects of chemoimmunotherapy in colon cancer-bearing aged mice.

Myeloid-derived suppressor cells (MDSCs) and regulatory T cells (Tregs) are increased in cancer-bearing aged hosts. Arginase-I in MDSCs degrades L-arginine, an amino acid required for T cell activation and proliferation. In this study, we compared the therapeutic efficacy of 5-fluorouracil (5-FU)/oxaliplatin (L-OHP) and cyclophosphamide (CP) between young and aged colon cancer-bearing mice. Therapy with 5-FU/L-OHP and CP significantly suppressed the in vivo growth of CT26 and MC38 colon carcinomas in syngeneic young mice, whereas this effect was attenuated in aged mice. L-arginine monotherapy showed no effect in aged mice. However, additional therapy with anti-programmed cell death (PD)-1 antibody and L-arginine supplementation boosted the effect of chemoimmunotherapy in aged mice, and some mice were cured. During all combination therapy, tumor-specific cytotoxic T lymphocytes (CTLs) were generated from mice with non-progressing tumor, but not from those with progressing tumor. Plasma L-arginine levels were lower in aged than young mice, and chemotherapy tended to decrease the plasma L-arginine levels in aged mice. Compared to young mice, CT26-bearing aged mice decreased arginase activity, arginase-I expression, and the proportion of monocytic MDSCs in tumor tissues, whereas contrasting results were observed in MC38-bearing aged mice. Importantly, the induction of tumor-specific CTLs was impaired at lower doses of L-arginine in vitro, and the infiltration of CTLs into CT26 tissues after chemoimmunotherapy was promoted by L-arginine administration in vivo. These results indicate that chemoimmunotherapy was less effective in cancer-bearing aged mice, but that L-arginine supplementation can modulate its therapeutic efficacy via its effect on tumor-specific CTLs.

Battling BTK mutants with noncovalent inhibitors that overcome Cys481 and Thr474 mutations in Waldenström macroglobulinemia therapy: structural mechanistic insights on the role of fenebrutinib.

Recently, the non-covalent Bruton tyrosine kinase (BTK) inhibitor fenebrutinib was presented as a therapeutic option with strong inhibitory efficacy against a single (C481S) and double (T474S/C481S) BTK variant in the treatment of Waldenström macroglobulinemia (WM). However, the molecular events surrounding its inhibition mechanism towards this variant remain unresolved. Herein, we employed in silico methods such as molecular dynamic simulation coupled with binding free energy estimations to explore the mechanistic activity of the fenebrutinib on (C481S) and (T474S/C481S) BTK variant, at a molecular level. Our investigations reveal that amino acid arginine contributed immensely to the total binding energy, this establishing the cruciality of amino acid residues, Arg132 and Arg156 in (C481S) and Arg99, Arg137, and Arg132 in (T474S/C481S) in the binding of fenebrutinib towards both BTK variants. The structural orientations of fenebrutinib within the respective hydrophobic pockets allowed favorable interactions with binding site residues, accounting for its superior binding affinity by 24.5% and relative high hydrogen bond formation towards (T474S/C481S) when compared with (C481S) BTK variants. Structurally, fenebrutinib impacted the stability, flexibility, and solvent accessible surface area of both BTK variants, characterized by various alterations observed in the bound and unbound structures, which proved enough to disrupt their biological function. Findings from this study, therefore, provide insights into the inhibitory mechanism of fenebrutinib at the atomistic level and reveal its high selectivity towards BTK variants. These insights could be key in designing and developing BTK mutants' inhibitors to treat Waldenström macroglobulinemia (WM).

Metabolomic profiling of bovine leucocytes transformed by Theileria annulata under BW720c treatment.

BACKGROUND: When Theileria annulata infects host cells, it undertakes unlimited proliferation as tumor cells. Although the transformed cells will recover their limited reproductive characteristics and enter the apoptosis process after treatment with buparvaquone (BW720c), the metabolites and metabolic pathways involved are not clear. METHODS: The transformed cells of T. annulata were used as experimental materials, and the buparvaquone treatment group and DMSO control group were used. Qualitative and quantitative analysis was undertaken of 36 cell samples based on the LC-QTOF platform in positive and negative ion modes. The metabolites of the cell samples after 72 h of drug treatment were analyzed, as were the different metabolites and metabolic pathways involved in the BW720c treatment. Finally, the differential metabolites and metabolic pathways in the transformed cells were found. RESULTS: A total of 1425 metabolites were detected in the negative ion mode and 1298 metabolites were detected in the positive ion mode. After drug treatment for 24 h, 48 h, and 72 h, there were 56, 162, and 243 differential metabolites in negative ion mode, and 35, 121, and 177 differential metabolites in positive ion mode, respectively. These differential metabolites are mainly concentrated on various essential amino acids. CONCLUSION: BW720c treatment induces metabolic disturbances in T. annulata-infected cells by regulating the metabolism of leucine, arginine, and L-carnitine, and induces host cell apoptosis.

Targeting amino acid metabolism in cancer.

Metabolic rewiring is a characteristic hallmark of cancer cells. This phenomenon sustains uncontrolled proliferation and resistance to apoptosis by increasing nutrients and energy supply. However, reprogramming comes together with vulnerabilities that can be used against tumor and can be applied in targeted therapy. In the last years, the genetic background of tumors has been identified thoroughly and new therapies targeting those mutations tested. Nevertheless, we propose that targeting the phenotype of cancer cells could be another way of treatment aiming to avoid drug resistance and non-responsiveness of cancer patients. Amino acid metabolism is part of the altered processes in cancer cells. Amino acids are building blocks and also sensors of signaling pathways regulating main biological processes. In this comprehensive review, we described four amino acids (asparagine, arginine, methionine, and cysteine) which have been actively investigated as potential targets for anti-tumor therapy. Asparagine depletion is successfully used for decades in the treatment of acute lymphoblastic leukemia and there is a strong implication to apply it to other types of tumors. Arginine auxotrophic tumors are great candidates for arginine-starvation therapy. Higher requirement for essential amino acids such as methionine and cysteine point out promising targetable weaknesses of cancer cells.

Grossamide attenuates inflammation by balancing macrophage polarization through metabolic reprogramming of macrophages in mice.

Macrophages exhibited different phenotypes in response to environmental cues. To meet the needs of rapid response to stimuli, M1-activated macrophages preferred glycolysis to oxidative phosphorylation (OXPHOS) in mitochondria to quickly produce energy and obtain ample raw materials to support cell activation at the same time. Activated macrophages produced free radicals and cytokines to eradicate pathogens but also induced oxidative damage and enhanced inflammation. Grossamide (GSE), a lignanamide from Polygonum multiflorum Thunb., exhibited notable anti-inflammatory effects. In this study, the potential of GSE on macrophage polarization was explored. GSE significantly down-regulated the levels of M1 macrophage biomarkers (Cd32a, Cd80 and Cd86) while increased the levels of M2 indicators (Cd163, Mrc1 and Socs1), showing its potential to inhibit LPS-induced M1 polarization of macrophages. This ability has close a link to its effect on metabolic reprogramming of macrophage. GSE shunted nitric oxide (NO) production from arginine by up-regulation of arginase and down-regulation of inducible nitric oxide synthase, thus attenuated the inhibition of NO on OXPHOS. LPS created three breakpoints in the tricarboxylic acid cycle (TCA) cycle of macrophage as evidenced by down-regulated isocitrate dehydrogenase, accumulation of succinate and the inhibited SDH activity, significantly decreased level of oxoglutarate dehydrogenase expression and its substrate α-ketoglutarate. Thus GSE reduced oxidative stress and amended fragmented TCA cycle. As a result, GSE maintained redox (NAD+/NADH) and energy (ATP/ADP) state, reduced extracellular acidification rate and enhanced the oxygen consumption rate. In addition, GSE decreased the release of inflammatory cytokines by inhibiting the activation of the LPS/TLR4/NF-κB pathway. These findings highlighted the central role of immunometabolism of macrophages in its functional plasticity, which invited future study of mode of action of anti-inflammatory drugs from viewpoint of metabolic reprogramming.