While treatment with surgery, radiotherapy and/or chemotherapy may prolong life for patients with glioblastoma, recurrence is inevitable. What is still being discovered is how much these treatments and recurrence of disease affect the molecular profiles of these tumors and how these tumors adapt to withstand these treatment pressures. Understanding such changes will uncover pathways used by the tumor to evade destruction and will elucidate new targets for treatment development.
View Article and Find Full Text PDFHeterogeneity is a hallmark of glioblastoma with intratumoral heterogeneity contributing to variability in responses and resistance to standard treatments. Promoter methylation status of the DNA repair enzyme O(6)-methylguanine DNA methyltransferase (MGMT) is the most important clinical biomarker in glioblastoma, predicting for therapeutic response. However, it does not always correlate with response.
View Article and Find Full Text PDFGlioblastomas, (grade 4 astrocytomas), are aggressive primary brain tumors characterized by histopathological heterogeneity. High-resolution sequencing technologies have shown that these tumors also feature significant inter-tumoral molecular heterogeneity. Molecular subtyping of these tumors has revealed several predictive and prognostic biomarkers.
View Article and Find Full Text PDFBackground: Broad or general consent given by cancer patients for their tissue, blood, and clinical information to be stored in institutional biorepositories is fundamental to enable future ethical translational cancer research. The decision to consent for biobanking will contribute to the development of advanced diagnostic and prognostic tests, as well as new therapies to improve patient outcomes. While the rate of patient participation in biobanking programs is generally reported as high worldwide, few studies have investigated factors that may influence this decision.
View Article and Find Full Text PDFBackground: MicroRNA 132 (miR-132) is dysregulated in a range of human malignancies; however, its role in glioma has not been reported. The aim of this study was to profile miR-132 expression in a cohort of patients with primary glioblastoma multiforme (GBM) treated with the Stupp regimen and to correlate microRNA levels with patient outcome.
Methods: miR-132 levels relative to RNU44 were assessed by quantitative reverse transcription-polymerase chain reaction in 43 GBMs and normal brain tissue.
Pancreatic stellate cells (PSC) produce the stromal reaction in pancreatic cancer, but their role in cancer progression is not fully elucidated. We examined the influence of PSCs on pancreatic cancer growth using (a) an orthotopic model of pancreatic cancer and (b) cultured human PSCs (hPSC) and human pancreatic cancer cell lines MiaPaCa-2 and Panc-1. Athymic mice received an intrapancreatic injection of saline, hPSCs, MiaPaCa-2 cells, or hPSCs + MiaPaCa-2.
View Article and Find Full Text PDFPurpose: Human ultraviolet light (UV) filters, such as kynurenine (Kyn), readily deaminate to reactive unsaturated ketones that covalently modify proteins in older human lenses. The aim of this study was to examine in vitro rates of formation and decomposition of the three major Kyn-amino acid adducts and possible consequences for the lens.
Methods: The t-Boc-protected Kyn-His, Kyn-Lys, and Kyn-Cys adducts and Kyn-Cys were synthesized from the corresponding amino acids and Kyn.
Free Radic Biol Med
November 2004
Human lens proteins become progressively modified by tryptophan-derived UV filter compounds in an age-dependent manner. One of these compounds, kynurenine, undergoes deamination at physiological pH, and the product binds covalently to nucleophilic residues in proteins via a Michael addition. Here we demonstrate that after covalent attachment of kynurenine, lens proteins become susceptible to photo-oxidation by wavelengths of light that penetrate the cornea.
View Article and Find Full Text PDFInvest Ophthalmol Vis Sci
March 2004
Purpose: Posttranslational modification by UV filters is a key event in human lenses that appears to be largely responsible for normal age-dependent yellowing. It has been proposed that subsequent reactions of these covalently bound UV filters may also be involved in the genesis of age-related nuclear cataract. To examine this hypothesis, the levels of kynurenine-lysine and kynurenine-histidine were measured in both normal and cataractous human lenses.
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