Search results for "MUTATION"
showing 10 items of 2830 documents
Functional characterisation of alpha-galactosidase a mutations as a basis for a new classification system in fabry disease.
2013
Fabry disease (FD) is an X-linked hereditary defect of glycosphingolipid storage caused by mutations in the gene encoding the lysosomal hydrolase α-galactosidase A (GLA, α-gal A). To date, over 400 mutations causing amino acid substitutions have been described. Most of these mutations are related to the classical Fabry phenotype. Generally in lysosomal storage disorders a reliable genotype/phenotype correlation is difficult to achieve, especially in FD with its X-linked mode of inheritance. In order to predict the metabolic consequence of a given mutation, we combined in vitro enzyme activity with in vivo biomarker data. Furthermore, we used the pharmacological chaperone (PC) 1-deoxygalacto…
MUTYH-associated tumor syndrome: The other face of MAP
2022
MUTYH gene is involved in the base excision repair (BER) mechanism and its pathogenic alterations are associated with colorectal polyposis and cancer. MUTYH-associated polyposis (MAP) is a condition which is inherited in an autosomal recessive manner. MAP patients, beyond colorectal cancer (CRC), may develop other types of tumors, including duodenal, breast, ovarian, pancreatic, bladder and skin cancers. Carriers of biallelic MUTYH likely pathogenic/pathogenic variants exhibit a high lifetime risk of CRC, though cancer risk evidence becomes less clear when monoallelic carriers and extraintestinal tumors are considered. However, several studies recently reported an increased genetic suscepti…
MYCN gain and MYCN amplification in a stage 4S neuroblastoma.
2003
Abstract Stage 4S neuroblastoma is a disease associated with spontaneous regression and good survival. We present a patient whose evolution has shown the variety and complexity of this disease in infants. Biologic factors, such as ploidy, MYCN copy number, loss of 1p36, and other chromosomal gains and losses were determined. A complex pattern of genetic abnormalities, such as near-diploidy, MYCN gain (2–4 copies per haploid genome) and imbalance/deletion of 1p36 was seen in the diagnostic sample. An extensive disseminated disease after a latent period of 26 months was associated with a special genetic evolution, such as tetraploidy, MYCN amplification (2:100–500 copies), 1p36 deletion, and …
TP53 mutations and hepatocellular carcinoma: insights into the etiology and pathogenesis of liver cancer.
2007
Hepatocellular carcinoma (HCC) is one of the most common malignancies worldwide and the major risk factors include chronic infections with the hepatitis B (HBV) or C (HCV) virus, and exposure to dietary aflatoxin B(1) (AFB(1)) or alcohol consumption. Multiple genetic and epigenetic changes are involved in the molecular pathogenesis of HCC, for example, somatic mutations in the p53 tumor suppressor gene (TP53) and the activation of the WNT signal transduction pathway. AFB(1) frequently induces G:C to T:A transversions at the third base in codon 249 of TP53 and cooperates with HBV in causing p53 mutations in HCC. The detection of TP53 mutant DNA in plasma is a biomarker of both AFB(1) exposur…
MYCN sensitizes human neuroblastoma to apoptosis by HIPK2 activation through a DNA damage response.
2010
Abstract MYCN amplification occurs in approximately 20% of human neuroblastomas and is associated with early tumor progression and poor outcome, despite intensive multimodal treatment. However, MYCN overexpression also sensitizes neuroblastoma cells to apoptosis. Thus, uncovering the molecular mechanisms linking MYCN to apoptosis might contribute to designing more efficient therapies for MYCN-amplified tumors. Here we show that MYCN-dependent sensitization to apoptosis requires activation of p53 and its phosphorylation at serine 46. The p53S46 kinase HIPK2 accumulates on MYCN expression, and its depletion by RNA interference impairs p53S46 phosphorylation and apoptosis. Remarkably, MYCN ind…
Genetic evolution of T-cell resistance in the course of melanoma progression
2014
Abstract Purpose: CD8+ T lymphocytes can kill autologous melanoma cells, but their activity is impaired when poorly immunogenic tumor phenotypes evolve in the course of disease progression. Here, we analyzed three consecutive melanoma lesions obtained within one year of developing stage IV disease for their recognition by autologous T cells. Experimental Design: One skin (Ma-Mel-48a) and two lymph node (Ma-Mel-48b, Ma-Mel-48c) metastases were analyzed for T-cell infiltration. Melanoma cell lines established from the respective lesions were characterized, determining the T-cell–stimulatory capacity, expression of surface molecules involved in T-cell activation, and specific genetic alteratio…
Application of patient-derived liver cancer cells for phenotypic characterization and therapeutic target identification.
2018
Primary liver cancer (PLC) ranks among the most lethal solid cancers worldwide due to lack of effective biomarkers for early detection and limited treatment options in advanced stages. Development of primary culture models that closely recapitulate phenotypic and molecular diversities of PLC is urgently needed to improve the patient outcome. Long-term cultures of 7 primary liver cancer cell lines of hepatocellular and cholangiocellular origin were established using defined culture conditions. Morphological and histological characteristics of obtained cell lines and xenograft tumors were analyzed and compared to original tumors. Time course analyses of transcriptomic and genomic changes were…
Role of two sequence motifs of mesencephalic astrocyte-derived neurotrophic factor in its survival-promoting activity
2015
AbstractMesencephalic astrocyte-derived neurotrophic factor (MANF) is a prosurvival protein that protects the cells when applied intracellularly in vitro or extracellularly in vivo. Its protective mechanisms are poorly known. Here we studied the role of two short sequence motifs within the carboxy-(C) terminal domain of MANF in its neuroprotective activity: the CKGC sequence (a CXXC motif) that could be involved in redox reactions, and the C-terminal RTDL sequence, an endoplasmic reticulum (ER) retention signal. We mutated these motifs and analyzed the antiapoptotic effect and intracellular localization of these mutants of MANF when overexpressed in cultured sympathetic or sensory neurons. …
The impact of oophorectomy on survival from breast cancer in patients with CHEK2 mutations
2022
BACKGROUND: To estimate the impact of oophorectomy and other treatments on the survival of breast cancer patients with a CHEK2 mutation. METHODS: Women with Stage I–III breast cancer who were treated at 17 hospitals in Poland were tested for four founder mutations in the CHEK2 gene. 974 women (10%) were positive for a CHEK2 mutation. Control patients without a CHEK2 mutation were selected from a database of patients treated over the same time period. Information on treatments received and distant recurrences were retrieved from medical records. Treatments included chemotherapy, hormonal therapy (tamoxifen) and radiation therapy. Oophorectomies were performed for the treatment of breast canc…
The “unnatural” history of colorectal cancer in Lynch syndrome : lessons from colonoscopy surveillance
2021
Individuals with Lynch syndrome (LS), one of the most common inherited cancer syndromes, are at increased risk of developing malignancies, in particular colorectal cancer (CRC). Regular colonoscopy with polypectomy is recommended to reduce CRC risk in LS individuals. However, recent independent studies demonstrated that a substantial proportion of LS individuals develop CRC despite regular colonoscopy. The reasons for this surprising observation confirmed by large prospective studies are a matter of debate. In this review, we collect existing evidence from clinical, epidemiological and molecular studies and interpret them with regard to the origins and progression of LS-associated CRC. Alon…