Uricase sensitizes hepatocellular carcinoma cells to 5-fluorouracil through uricase-uric acid-UMP synthase axis

Conventional chemotherapy plays a key role in hepatocellular carcinoma (HCC) treatment, however, with intrinsic or acquired chemoresistance being a major constraint. Here, we aimed to identify potential target to reverse such chemoresistance. In the present study, we found significant difference in uridine monophosphate synthetase (UMPS) expression between 5-FU resistant and sensitive HCC cell lines and the overexpression or downregulation of UMPS impacted 5-FU response in HCC cells. We further found that inhibition of UMPS activity with uric acid at concentration present in human plasma decreased the 5-FU sensitivity of HCC cells, while reduction of uric acid levels with uricase improved the 5-FU sensitivity of HCC cells as well as colorectal cancer cells. In vivo studies also suggested that modulation of uric acid levels did affect 5-FU sensitivity of tumors. These data indicated that UMPS was correlated with the 5-FU resistance in HCC cells and uricase sensitized cancer cells to 5-FU through uricase-uric acid-UMP synthase axis, which provided a potential strategy to improve the efficacy of 5-FU-based chemotherapy for human cancers. (AU)

Prognostic role of NLGN2 and PTGDS in medulloblastoma based on gene expression omnibus.

BACKGROUND: Medulloblastoma (MB) is the most common intracranial malignant tumour in children, but genes and pathways involved in its pathogenesis are still under investigation. This study was designed to screen and identify biomarkers of MB to provide markers for clinical diagnosis and prognosis assessment. METHODS: The data sets of GSE109401 and GSE42656 were acquired from Gene expression omnibus (GEO). Limma package in R was adopted to identify the differentially expressed genes (DEGs), and the GSE30074 data set was adopted to analyse their prognostic role. Children with MB (n=55) diagnosed in Affiliated Ezhou Central Hospital were enrolled and assigned to the patient group, and healthy children (n=30) who received physical examination in our hospital during the same time period were assigned to the control group. The two groups were compared in serum NLGN2 and PTGDS levels, and all patients were followed up for three years to understand the associations of Neuroligin 2 (NLGN2) and Prostaglandin D2 synthase (PTGDS) with the survival of patients. RESULTS: With Limma, 247 DEGs were screened out. The LASSO-Cox regression analysis revealed that 6 genes were associated with MB prognosis, and the established model revealed a lower survival rate in the high-risk group. According to Cox regression analysis, NLGN2 and PTGDS may be independent prognostic factors of MB. Similar to the data sets, the Real time-quantitative polymerase chain reaction (RT-qPCR) assay revealed lowly-expressed NLGN2 and PTGDS levels in MB patients, and patients with lower expression of them showed a lower 3-year survival rate. CONCLUSION: With low expression in MB cases, NLGN2 and PTGDS have high prognostic value for MB.

Uricase sensitizes hepatocellular carcinoma cells to 5-fluorouracil through uricase-uric acid-UMP synthase axis.

Conventional chemotherapy plays a key role in hepatocellular carcinoma (HCC) treatment, however, with intrinsic or acquired chemoresistance being a major constraint. Here, we aimed to identify potential target to reverse such chemoresistance. In the present study, we found significant difference in uridine monophosphate synthetase (UMPS) expression between 5-FU resistant and sensitive HCC cell lines and the overexpression or downregulation of UMPS impacted 5-FU response in HCC cells. We further found that inhibition of UMPS activity with uric acid at concentration present in human plasma decreased the 5-FU sensitivity of HCC cells, while reduction of uric acid levels with uricase improved the 5-FU sensitivity of HCC cells as well as colorectal cancer cells. In vivo studies also suggested that modulation of uric acid levels did affect 5-FU sensitivity of tumors. These data indicated that UMPS was correlated with the 5-FU resistance in HCC cells and uricase sensitized cancer cells to 5-FU through uricase-uric acid-UMP synthase axis, which provided a potential strategy to improve the efficacy of 5-FU-based chemotherapy for human cancers.

Case Report: A Novel Missense Mutation c.517G>C in the UMPS Gene Associated With Mild Orotic Aciduria.

Background: Hereditary orotic aciduria (HOA) is a rare genetic disorder of pyrimidine metabolism caused by variations in the uridine monophosphate synthetase (UMPS) gene and inheritance are autosomal recessive. Heterozygous UMPS mutations can also lead to orotic aciduria without clinical consequence. Methods: We conducted molecular genetic analyses on proband using whole-exome sequencing (WES) and on 12 family members using Sanger sequencing for UMPS mutation. We analyzed the urine metabolites of family members carrying UMPS heterozygous variants with standard gas chromatography-mass spectrometry (GC-MS). Results: We identified a novel UMPS mutation (c.517G>C) in a Chinese-origin of orotic aciduria pedigree. The proband presented with epilepsy and intellectual disability (ID). Other mutation carriers in our pedigree presented with mild orotic aciduria without relevant medical complaints except for the proband. Conclusion: Our study further expanded the genotype of orotic aciduria and highlighted the probability of misdiagnosis in clinical practice.

Laparoscopic Castration Using Bipolar Forceps vs. Orchiectomy in Dogs: A Comparison of Two Techniques.

This paper aimed to study the feasibility of a new laparoscopic castration technique in male dogs, evaluate the pain associated with it, and compare it with the classical orchiectomy. Surgical times, pain scores, blood and salivary cortisol, and CRP were recorded and compared between the two groups. The use of high-frequency bipolar forceps allowed quick and uneventful laparoscopic procedures. The laparoscopic group had significantly lower pain scores, cortisol, and PCR values than the orchiectomy group. No complications were seen in any group. Our results suggest that this laparoscopic castration is a safe and beneficial surgical alternative to traditional orchiectomy in dogs.

Modulating pyrimidine ribonucleotide levels for the treatment of cancer.

By providing the necessary building blocks for nucleic acids and precursors for cell membrane synthesis, pyrimidine ribonucleotides are essential for cell growth and proliferation. Therefore, depleting pyrimidine ribonucleotide pools has long been considered as a strategy to reduce cancer cell growth. Here, we review the pharmacological approaches that have been employed to modulate pyrimidine ribonucleotide synthesis and degradation routes and discuss their potential use in cancer therapy. New developments in the treatment of myeloid malignancies with inhibitors of pyrimidine ribonucleotide synthesis justify revisiting the literature as well as discussing whether targeting this metabolic pathway can be effective and sufficiently selective for cancer cells to warrant an acceptable therapeutic index in patients.

Identification of Circulating Genomic and Metabolic Biomarkers in Intrahepatic Cholangiocarcinoma.

Intrahepatic cholangiocarcinoma (ICC) is an aggressive cancer arising from the bile ducts with a need for earlier diagnosis and a greater range of treatment options. KRAS/NRAS mutations are common in ICC tumours and 6-32% of patients also have isocitrate dehydrogenase 1 and 2 (IDH1 and IDH2) gene mutations associated with metabolic changes. This feasibility study investigated sequencing circulating tumour DNA (ctDNA) combined with metabolite profiling of plasma as a method for biomarker discovery in ICC patients. Plasma was collected from four ICC patients receiving radio-embolisation and healthy controls at multiple time points. ctDNA was sequenced using Ampliseq cancer hotspot panel-v2 on Ion Torrent PGM for single nucleotide variants (SNV) detection and with Illumina whole genome sequencing for copy number variants (CNV) and further targeted examination for SNVs. Untargeted analysis of metabolites from patient and control plasma was performed using liquid chromatography coupled with high-resolution tandem mass spectrometry (LC-MS/MS). Metabolite identification was performed using multi-parameter comparisons with analysis of authentic standards, and univariate statistical analysis was performed to identify differences in metabolite abundance between patient and control samples. Recurrent somatic SNVs and CNVs were identified in ctDNA from three out of four patients that included both NRAS and IDH1 mutations linked to ICC. Plasma metabolite analysis revealed biomarker metabolites associated with ICC and in particular 2-hydroxyglutarate (2-HG) levels were elevated in both samples from the only patient showing a variant allele in IDH1. A reduction in the number of CNVs was observed with treatment. This study demonstrates that ctDNA and metabolite levels can be identified and correlated in ICC patient blood samples and differentiated from healthy controls. We conclude that combining genomic and metabolic analysis of plasma offers an effective approach to biomarker identification with potential for disease stratification and early detection studies.

Difusión analgésica de lidocaína administrada a través de un catéter perilesional en hembras caninas sometidas a mastectomía: un reporte de caso / Analgesic diffusion of lidocaine administered through a wound soaker catheter in female canines undergoing mastectomy: a case report / Difusão analgésica de lidocaína administrada por um catéter perilesional em cadelas submetidas à mastectomía: um relato de caso

Resumen La mastectomía regional en caninos se considera un procedimiento quirúrgico con un grado de dolor intenso, por lo que exige una terapéutica analgésica posquirúrgica efectiva que actúe a favor del bienestar de los pacientes. El manejo farmacológico analgésico sistémico convencional en pacientes de carácter oncológico es deficiente y está fundamentado principalmente en antinflamatorios no esteroidales (AINEs) u opioides de baja potencia. El objetivo del presente reporte es describir el manejo analgésico posmastectomía en dos hembras caninas, mediante el uso de lidocaína como opción fármaco-terapéutica administrada a través de un catéter de difusión analgésica perilesional (MILA ®). Ambos pacientes fueron sometidos a mastectomía regional. Luego de retirar la masa mamaria para cada caso, se instauró un catéter perilesional y se administró lidocaína a 2 mg/kg/ hora de forma intralesional, mediante difusión constante por medio de un catéter y una jeringa perfusora. Se realizaron mediciones de variables fisiológicas y de dolor mediante la escala de la Universidad de Melbourne (UMPS) en ambos pacientes cada 2 horas (T0-T12) durante 24 horas. Ambos pacientes mostraron un descenso en el score de la UMPS durante el periodo de observación posquirúrgica y no hubo cambios significativos en las mediciones de las variables fisiológicas. La infusión intralesional de lidocaína aplicada en los dos pacientes sometidos a mastectomía del presente reporte logró un estado de analgesia posquirúrgico efectivo.

Abstract The regional mastectomy in canines is considered as an intense-pain degree surgical procedure in bitches, which requires an effective post-sur-gical analgesic therapy for the well-being of patients. The conventional systemic analgesic pharmacological management in oncological patients is deficient and is mainly based on non-steroidal anti-inflammatory drugs (NSAIDs) and/or low potency opioids. The present report aimed to describe post-mastectomy analgesic management in two bitches, using lidocaine as a drug-therapeutic option administered through a perilesional anal- gesic diffusion catheter (MILA®). Both patients were subjected to regional mastectomy. After removing the breast mass for each case, a perilesional catheter was placed and the lidocaine was administered at 2 mg/kg/hour intralesionally, by constant diffusion through a catheter and a perfusion syringe. Measurements of physiological and pain variables were collected using the University of Melbourne Scale (UMPS) in both patients every 2 hours (T0-T12) for 24 hours. Both patients showed a decrease in UMPS score during the post-surgical observation period and there were no sig- nificant changes in the measurements of the physiological variables. The intralesional infusion of lidocaine applied in the two patients subjected to mastectomy on this report achieved an effective post-surgical analgesia state.

Resumo A mastectomía regional em caninos é considerada um procedimento cirúrgico comgrau de dor intenso, que requer uma terapia analgésica pós-cirúrgica efetiva que atue em o bem-estar dos pacientes. A terapia farmacológica sistémica analgésico convencional nestes pacientes de características oncológicas é mau e baseada principalmente na antinflamatorios não esteroide (AINE) e/ou de opioides baixa potência. O objetivo deste trabalho é descrever a terapia analgésica pós-mastectomía dois cães fêmeas, através da utilização de lidocaína como opção terapêutico medicamentoso administrado o fármaco através de um cateter de difusão perilesional analgésico (MILA®). Duas cadelas foram submetidas a mastectomía regional. Após a remoção da massa mamária para cada caso, um cateter perilesional foi colocado e lidocaína foi administrada a 2 mg/kg/hora por via intralesional, por difusão constante através de cateter e seringa de perfusão. Medidas de variáveis fisiológicas e de dor foram feitas usando a escala da Universidade de Melbourne (UMPS) em ambos os pacientes a cada 2 horas (T0-T12) por 24 horas. Ambos pacientes mostraram uma diminuição no escore de dor de UMPS durante o período de observação pós-cirúrgica e não houve mudanças significativas nas medidas das variáveis fisiológicas. A infusão intralesional de lidocaína aplicada nas duas cadelas submetidos à mastectomía deste relato alcançou um estado analgésico pós-operatório eficaz.

BCL-2 family protein BOK is a positive regulator of uridine metabolism in mammals.

BCL-2 family proteins regulate the mitochondrial apoptotic pathway. BOK, a multidomain BCL-2 family protein, is generally believed to be an adaptor protein similar to BAK and BAX, regulating the mitochondrial permeability transition during apoptosis. Here we report that BOK is a positive regulator of a key enzyme involved in uridine biosynthesis; namely, uridine monophosphate synthetase (UMPS). Our data suggest that BOK expression enhances UMPS activity, cell proliferation, and chemosensitivity. Genetic deletion of Bok results in chemoresistance to 5-fluorouracil (5-FU) in different cell lines and in mice. Conversely, cancer cells and primary tissues that acquire resistance to 5-FU down-regulate BOK expression. Furthermore, we also provide evidence for a role for BOK in nucleotide metabolism and cell cycle regulation. Our results have implications in developing BOK as a biomarker for 5-FU resistance and have the potential for the development of BOK-mimetics for sensitizing 5-FU-resistant cancers.

Physiologic Medium Rewires Cellular Metabolism and Reveals Uric Acid as an Endogenous Inhibitor of UMP Synthase.

A complex interplay of environmental factors impacts the metabolism of human cells, but neither traditional culture media nor mouse plasma mimic the metabolite composition of human plasma. Here, we developed a culture medium with polar metabolite concentrations comparable to those of human plasma (human plasma-like medium [HPLM]). Culture in HPLM, relative to that in traditional media, had widespread effects on cellular metabolism, including on the metabolome, redox state, and glucose utilization. Among the most prominent was an inhibition of de novo pyrimidine synthesis-an effect traced to uric acid, which is 10-fold higher in the blood of humans than of mice and other non-primates. We find that uric acid directly inhibits uridine monophosphate synthase (UMPS) and consequently reduces the sensitivity of cancer cells to the chemotherapeutic agent 5-fluorouracil. Thus, media that better recapitulates the composition of human plasma reveals unforeseen metabolic wiring and regulation, suggesting that HPLM should be of broad utility.