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Is Lactate an Oncometabolite? Evidence Supporting a Role for Lactate in the Regulation of Transcriptional Activity of Cancer-Related Genes in MCF7 Breast Cancer Cells.
Lactate is a ubiquitous molecule in cancer. In this exploratory study, our aim was to test the hypothesis that lactate could function as an oncometabolite by evaluating whether lactate exposure modifies the expression of oncogenes, or genes encoding transcription factors, cell division, and cell proliferation in MCF7 cells, a human breast cancer cell line. Gene transcription was compared between MCF7 cells incubated in (a) glucose/glutamine-free media (control), (b) glucose-containing media to stimulate endogenous lactate production (replicating some of the original Warburg studies), and (c) glucose-containing media supplemented with L-lactate (10 and 20 mM). We found that both endogenous, glucose-derived lactate and exogenous, lactate supplementation significantly affected the transcription of key oncogenes (MYC, RAS, and PI3KCA), transcription factors (HIF1A and E2F1), tumor suppressors (BRCA1, BRCA2) as well as cell cycle and proliferation genes involved in breast cancer (AKT1, ATM, CCND1, CDK4, CDKN1A, CDK2B) (0.001 < p < 0.05 for all genes). Our findings support the hypothesis that lactate acts as an oncometabolite in MCF7 cells. Further research is necessary on other cell lines and biopsy cultures to show generality of the findings and reveal the mechanisms by which dysregulated lactate metabolism could act as an oncometabolite in carcinogenesis
Trasplante óseo
We describe the methodology of the Bone and Soft Tissue
Bank, from extraction and storage until use.
Since the year 1986, with the creation of the Bone Bank
in the University Clinic of Navarra, more than 3,000 grafts
have been used for very different types of surgery.
Bone grafts can be classified into cortical and
spongy; the former are principally used in surgery to save
tumour patients, in large post-traumatic reconstructions
and in replacement surgery where there are massive
bone defects and a structural support is required. The
spongy grafts are the most used due to their numerous
indications; they are especially useful in filling cavities
that require a significant quantity of graft when the autograft
is insufficient, or as a complement. They are also of
special help in treating fractures when there is bone loss
and in the treatment of delays in consolidation and
pseudoarthrosis in little vascularized and atrophic zones.
They are also used in prosthetic surgery against the presence
of cavity type defects.
Allografts of soft tissues are specially recognised in
multiple ligament injuries that require reconstructions.
Nowadays, the most utilised are those employed in surgery
of the anterior cruciate ligament although they can be used
for filling any ligament or tendon defect.
The principal difficulties of the cortical allografts are
in the consolidation of the ends with the bone itself and in
tumour surgery, given that these are patients immunodepressed
by the treatment, the incidence of infection is
increased with respect to spongy grafts and soft tissues,
which is irrelevant.
In short, the increasingly widespread use of allografts
is an essential therapeutic weapon in orthopaedic
surgery and traumatology. It must be used by expert
hands
Changes in objectively measured sleep after a multidisciplinary lifestyle intervention in children with abdominal obesity: A randomized trial
Background/objective: childhood obesity and sleep disorders have a well-established cross-sectional association,
but lifestyle interventions’ effects on sleep quality remain under-researched. This study aimed to evaluate the
sleep quality of 122 participants (7–16 years) with abdominal obesity after a 2-year necessary lifestyle
intervention.
Patients/methods: participants were assigned to either the intervention group (moderate hypocaloric Mediterranean Diet) or the usual care group (standard recommendations on a healthy diet). Sleep was objectively
assessed using triaxial accelerometry, and sleep parameters analyzed included latency, efficiency, wake after
sleep onset, total time in bed, total sleep time, number of awakenings, and awakening duration.
Results and conclusions: the results showed that the intervention group significantly improved sleep latency at 12
and 24 months and improved sleep efficiency at 2 and 12 months, compared to the usual care group. Wake after
sleep onset and the number of awakenings were significantly reduced at 24 months in the intervention group.
Wake after sleep onset and leptin levels were positively associated in all participants. Total time in bed was
inversely associated with triglycerides and metabolic score, and total sleep time was inversely associated with
leptin, triglycerides, and metabolic score after the 2-month intervention. Triglyceride levels were inversely
associated with total time in bed and total sleep time at one year, while the metabolic score was directly
associated with wake after sleep onset and the number of awakenings and inversely associated with efficiency. In
conclusion, the multidisciplinary intervention in children and adolescents with abdominal obesity reduced
anthropometric parameters and improved sleep habits
Bone Mineral Density and Bone Metabolism In Children Treated for Bone Sarcomas
In adolescent bone sarcoma patients, bone mass acquisition is potentially compromised at a time in which it should be at a maximum. To evaluate the problem we measured bone mineral density (BMD) and serum markers of bone formation and resorption in a series of pediatric patients with bone tumors. BMD was measured by dual-energy x-ray absorptiometry, at clinical remission, for lumbar spine and the neck of the femur in 38 osteosarcoma and 25 Ewing's sarcoma patients. Mean age was 20.65 and 19.13 y respectively. Serum markers of bone metabolism were: OC, PICP, ICTP, 25-OH vit D and 1,25-(OH)(2) vit D, IGF-I, IGFBP-3 and intact PTH. Serum was sampled throughout anti-tumoral treatments and follow-up. We analyzed 85 samples from 59 osteosarcoma patients and 54 samples from 36 Ewing's sarcoma patients. Patients had decreased lumbar and femoral BMD. The decrease was more pronounced in pubertal patients compared with those who had completed pubertal development at the time of disease diagnosis. Multivariate analysis indicated that sex, age, weight and BMI were significant in lumbar BMD depletion. Weight and BMI were significant in femoral BMD depletion. Serum markers of bone formation (PICP and OC) and resorption (ICTP) were, throughout, lower than reference values. Significant alterations in other markers were also observed. Up to a third of osteosarcoma and Ewing's sarcoma patients in clinical remission had some degree of BMD deficit. The corresponding increased risk of pathologic bone fractures constitutes a reduction in future quality o
Methotrexate in Pediatric Osteosarcoma: Response and Toxicity in Relation to Genetic Polymorphisms and Dihydrofolate Reductase and Reduced Folate Carrier 1 Expression
To determine the influence of the genotype and the level of expression of different enzymes involved in folate metabolism on the response to and toxicity of high-dose methotrexate treatment in pediatric osteosarcomas.
STUDY DESIGN: DHFR and Reduced folate carrier 1 (RFC1) semiquantitative expression was analyzed in 34 primary and metastatic osteosarcoma tissues by real-time polymerase chain reaction. The following polymorphisms were also analyzed in peripheral blood from 96 children with osteosarcoma and 110 control subjects: C677T, A1298C (MTHFR), G80A (RFC1), A2756G (MTR), C1420T (SHMT), the 28bp-repeat polymorphism, and 1494del6 of the TYMS gene. Treatment toxicity was scored after each cycle according to criteria from the World Health Organization.
RESULTS: DHFR and RFC1 expression was lower in initial osteosarcoma biopsy specimens than in metastases (P = .024 and P = .041, respectively). RFC1 expression was moderately decreased in samples with poor histologic response to preoperative treatment (P = .053). Patients with osteosarcoma with G3/G4 hematologic toxicity were more frequently TT than CT/CC for C677T/MTHFR (P = .023) and GG for A2756G/MTR (P = .048 and P = .057 for gastrointestinal and hematologic toxicity, respectively).
CONCLUSIONS: The role of C677T/MTHFR and A2756G/MTR on chemotherapy-induced toxicity should be further investigated in pediatric osteosarcomas receiving high-dose methotrexate. Altered expression of DHFR and RFC1 is a feasible mechanism by which osteosarcoma cells become resistant to methotrexate
Analysis of Polymorphisms of the Vitamin D Receptor, Estrogen Receptor, and Collagen Iα1 Genes and Their Relationship With Height in Children With Bone Cancer
The authors' objectives were to compare height at diagnosis of children
with bone tumors with that of Spanish reference children; to analyze the
frequency of the genotypes for the polymorphisms of the vitamin D receptor (VDR),
estrogen receptor (ER), and collagen Ialpha1 (COLIalpha1) genes in patients and
in healthy controls; and to test the relationship between the genetic markers and
height. PATIENTS AND METHODS: Height and weight at diagnosis were measured in 58
osteosarcoma and 36 Ewing sarcoma patients and compared with standards published
for Spanish reference children according to sex and age. For the molecular
analysis, genetic polymorphisms of the VDR (Fok I, Apa I, and TaqI), ER (Pvu II
and XbaI), and COLIalpha1 (Msc I) genes were characterized in 72 osteosarcoma and
53 Ewing sarcomas and in a group of 143 healthy matched children. RESULTS:
Osteosarcoma and Ewing sarcoma patients were significantly taller than Spanish
reference children. Osteosarcoma patients showed a significantly higher frequency
of the Ff genotype for the Fok I polymorphism (VDR gene) than the control group.
The odds ratio for this genotype was 1.78, with an increased relative risk of 78%
for heterozygous Ff carriers. Among Ewing sarcoma patients, this same genotype
was significantly associated with lower height than homozygotes (FF or ff).
CONCLUSIONS: Children with bone cancer are significantly taller than the
reference population, which may be influenced by the genotype for the Fok I
polymorphism of the VDR gene
Estudio PET-TC con 18F-fluoro-L-DOPA combinado con el análisis genético para la optimización de la clasificación y tratamiento de un niño con hiperinsulinismo congénito grave
Abstract
BACKGROUND:
Congenital hyperinsulinism (CHI) is the most common cause of persistent hypoglycaemia in infancy. The differential diagnosis between focal and diffuse forms of CHI is of great importance when planning surgery. The aim of this article is to show the first case of focal CHI diagnosed in Spain using PET-CT imaging combined with genetic analysis.
METHODS:
A 13 month child with CHI and normal conventional radiological investigations treated with diazoxide, diet control and feeding by gastrostomy is presented. Genetic analysis of ABCC8 and KCNJ11 genes and PET-TAC using 18F-fluoro-L-DOPA were performed.
RESULTS:
A pathological mutation (G111R) in the paternal allele of ABCC8 was detected. PET-CT scanning using 18F-fluoro-L-DOPA showed a focus of high uptake in the body of the pancreas compatible with adenoma that was hystopathologically confirmed. After surgical resection the patient is asymptomatic without needing either pharmacological treatment or dietetic control.
CONCLUSIONS:
The combination of genetic analysis and 18F-fluoro-L-DOPA PET-TAC shows a great potential for the identification, location and guideline for surgery in CHI
A hot spot on interferon α/β receptor subunit 1 (IFNAR1) underpins its interaction with interferon-β and dictates signaling
The interaction of IFN-β with its receptor IFNAR1 (interferon α/β receptor subunit 1) is vital for host-protective anti-viral and anti-proliferative responses, but signaling via this interaction can be detrimental if dysregulated. Whereas it is established that IFNAR1 is an essential component of the IFNAR signaling complex, the key residues underpinning the IFN-β-IFNAR1 interaction are unknown. Guided by the crystal structure of the IFN-β-IFNAR1 complex, we used truncation variants and site-directed mutagenesis to investigate domains and residues enabling complexation of IFN-β to IFNAR1. We have identified an interface on IFNAR1-subdomain-3 that is differentially utilized by IFN-β and IFN-α for signal transduction. We used surface plasmon resonance and cell-based assays to investigate this important IFN-β binding interface that is centered on IFNAR1 residues Tyr240 and Tyr274 binding the C and N termini of the B and C helices of IFN-β, respectively. Using IFNAR1 and IFN-β variants, we show that this interface contributes significantly to the affinity of IFN-β for IFNAR1, its ability to activate STAT1, the expression of interferon stimulated genes, and ultimately to the anti-viral and anti-proliferative properties of IFN-β. These results identify a key interface created by IFNAR1 residues Tyr240 and Tyr274 interacting with IFN-β residues Phe63, Leu64, Glu77, Thr78, Val81, and Arg82 that underlie IFN-β-IFNAR1-mediated signaling and biological processes
Somatic and germline analysis of a familial Rothmund-Thomson syndrome in two siblings with osteosarcoma
Rothmund–Thomson syndrome (RTS) is characterized by a rash that begins in the first few months of life and eventually develops into poikiloderma. Associated symptoms are alterations in the teeth, sparse hair, thin eyebrows, lack of eyelashes, low stature, bone abnormalities, hematological illnesses, gastrointestinal disease, malnutrition, cataracts, and predisposition to cancer, principally to bone tumors and skin cancer. Diagnostic certitude is provided by a genetic study involving detection of pathogenic variants of the RECQL4 gene. We hereby present a familiar case of RTS in two siblings from a Portuguese family, both diagnosed with osteosarcoma. Genomic analysis (203 genes) of both tumors as well as germline analysis of the RECQL4 gene, thus confirming the syndrome in the family, have been performed. The relevance of clinical recognition of the hallmarks of the disease and thus early diagnosis with early intervention is highlighted
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