Pyruvate carboxylase (PC) is an enzyme catalyzing the carboxylation of pyruvate to oxaloacetate. The enzymatic generation of oxaloacetate, an intermediate of the Krebs cycle, could provide the cancer cells with the additional anaplerotic capacity and promote their anabolic metabolism. Recent studies revealed that several types of cancer cells express PC.
View Article and Find Full Text PDFDeregulation of signalling pathways that regulate cell growth, survival, metabolism, and migration can frequently lead to the progression of cancer. Brain tumours are a large group of malignancies characterised by inter- and intratumoral heterogeneity, with glioblastoma (GBM) being the most aggressive and fatal. The present study aimed to characterise the expression of cancer pathway-related genes ( = 84) in glial tumour cell lines (A172, SW1088, and T98G).
View Article and Find Full Text PDFBackground: Glioblastoma (GB) is the most common and biologically the most aggressive primary brain tumor of the central nervous system (CNS) in adults. Standard treatment for newly diagnosed GB consists of surgical resection, radiotherapy, and chemotherapy with temozolomide (TMZ). Despite numbers of studies, a resistance to chemotherapy is the major obstacle to successful GB treatment.
View Article and Find Full Text PDFLeucine is an essential, ketogenic amino acid with proteinogenic, metabolic, and signaling roles. It is readily imported from the bloodstream into the brain parenchyma. Therefore, it could serve as a putative substrate that is complementing glucose for sustaining the metabolic needs of brain tumor cells.
View Article and Find Full Text PDFAs the commonest type of cancer in Europe and the third most common type of cancer worldwide, colorectal carcinoma (CRC) poses a challenge for numerous scientific studies. At present, the cause of this disease is remains to be elucidated, but early diagnosis is only one solution to prevent serious health complications. As a structural scaffold, the extracellular matrix (ECM) is in direct contact with tumour cells and significantly interferes with tumour progression.
View Article and Find Full Text PDFSenescence is an irreversible permanent cell cycle arrest accompanied by changes in cell morphology and physiology. Bioactive compounds including tocotrienols (vitamin E) can affect important biological functions. The aim of this study was to investigate how γ- and δ-tocotrienols can affect stress-induced premature senescence.
View Article and Find Full Text PDFThe brain tumours represent a complex tissue that has its own characteristic metabolic features and is interfaced with the whole organism. We investigated changes in basal blood plasma metabolites in the presence of primary brain tumour, their correlation with tumour grade, as well as the feasibility of statistical discrimination based on plasma metabolites. Together 60 plasma samples from patients with clinically defined glioblastoma, meningioma, oligodendrioglioma, astrocytoma, and non-specific glial tumour and plasma samples from 28 healthy volunteers without any cancer history were measured by NMR spectroscopy.
View Article and Find Full Text PDFThe aim our study was to investigate protective effect of cobalt chloride (CoCl2) in the model of proteasome stress of neuroblastoma SH-SY5Y cells induced by bortezomib, an inhibitor of 26S proteasome. We have focused our interests on Hsp70 and activation of caspase 3. Finally, we have compared the effect of CoCl2 with an effect of the pre-treatment of the cells with 17-AAG, an inhibitor of Hsp90 that is capable to induce expression of Hsp70, or with IOX2, an inhibitor of isoform 2 of prolyl hydroxylase that increases stability of hypoxia inducible factor 1α (HIF1α).
View Article and Find Full Text PDFEndometrial carcinoma is one of the most common tumours in developed countries. In addition to the active role of genetic factors, epigenetic changes also have an important effect. The present study analysed the methylation status of kruppel like factor 4 (KLF4) and heparan sulfate‑glucosamine 3‑sulfotransferase 2 (HS3ST2) genes in three endometrial tissue types for carcinoma prediction.
View Article and Find Full Text PDFMetastatic breast cancer is characterized by aggressive spreading to distant organs. Despite huge multilevel research, there are still several important challenges that have to be clarified in the management of this disease. Therefore, recent investigations have implemented a modern, multiomic approach with the aim of identifying specific biomarkers for not only early detection but also to predict treatment responses and metastatic spread.
View Article and Find Full Text PDFBackground: Apoptosis plays an important role in the development and homeostasis of multicellular organisms and its deregulation may result in many serious diseases, including cancer. Now it is clear that some oncogenic mutations disrupt apoptosis, leading to tumour initiation, progression or metastasis. Here, expression of apoptotic genes in context of drug resistance was investigated.
View Article and Find Full Text PDFColorectal carcinoma (CRC) that represents one of the major causes for cancer-related death in humans is often associated with over-expression of anti-apoptotic proteins of Bcl-2 family. The aim of presented study was to determine the effect of ABT-737 inhibitor of anti-apoptotic proteins Bcl-2, Bcl-XL and Bcl-w as well as cyclin-dependent kinase 2 (CDK2) inhibitor SU9516 alone and in combination with ABT-737 on survival of colorectal cell lines HT29 and Caco-2. We have shown that both Caco-2 and HT29 cells that are relatively resistant to ABT-737 are also partially sensitive to SU9516, which increased sensitivity of Caco-2 but not HT29 cells to ABT-737.
View Article and Find Full Text PDFDNA methylation is a significant epigenetic modification which plays a key role in regulation of gene expression and influences functional changes in endometrial tissue. Aberrant DNA methylation changes result in deregulation of important apoptotic proteins during endometrial carcinogenesis and apoptosis resistance development. Evading apoptosis is still a major problem in the successful treatment of endometrial cancer patients.
View Article and Find Full Text PDFAlterations in enzymatic activities underlying the cellular capacity to maintain functional S-adenosylmethionine (SAM) cycle are associated with modified levels of its constituents. Since SAM is the most prominent donor of methyl group for sustaining the methylation pattern of macromolecules by methyltransferases, its availability is an essential prerequisite for sustaining the methylation pattern of nucleic acids and proteins. In addition, increased intracellular concentrations of S-adenosylhomocysteine and homocysteine, another two constituents of SAM cycle, exerts an inhibitory effect on the enzymatic activity of methyltranferases.
View Article and Find Full Text PDFAndrogens play an important role during the development of both normal prostate epithelium and prostate cancer and variants of genes involved in androgen metabolism may be related to an increased risk of prostate disease. Cytochrome P450 17α-hydroxylase/17,20-lyase (CYP17A1) is a key regulatory enzyme in the steroidogenic pathway; it catalyses both 17α-hydroxylase and 17,20-lyase activities and is essential for the production of both androgens and glucocorticoids. In this review, we focus on the structure and enzymatic activity of CYP17A1 and the mechanism of modulation of CYP17A1 activities.
View Article and Find Full Text PDFOverload or dysfunction of ubiquitin-proteasome system (UPS) is implicated in mechanisms of neurodegeneration associated with neurodegenerative diseases, e.g. Parkinson and Alzheimer disease, and ischemia-reperfusion injury.
View Article and Find Full Text PDFGlioblastoma (GB) is the most frequent and biologically the most aggressive primary brain tumor in adults. Standard treatment for newly diagnosed GB consists of surgical resection, radiotherapy and chemotherapy. Resistance to therapy is a major obstacle, even with optimal treatment with a survival median of only 12-15 months.
View Article and Find Full Text PDFDuring the normal menstrual cycle, endometrial tissue undergoes many biochemical and morphological changes which are under the control of steroid hormone levels. DNA methylation plays a key role in gene expression regulation and influences functional changes in endometrial tissue. Eliminating senescent cells from the functional layer of the endometrium is mediated by apoptotic cell death, which helps maintain cellular homeostasis.
View Article and Find Full Text PDFThe most prominent function of proteins of the Bcl-2 family is regulation of the initiation of intrinsic (mitochondrial) pathways of apoptosis. However, recent research has revealed that in addition to regulation of mitochondrial apoptosis, proteins of the Bcl-2 family play important roles in regulating other cellular pathways with a strong impact on cell survival like autophagy, endoplasmic reticulum (ER) stress response, intracellular calcium dynamics, cell cycle progression, mitochondrial dynamics and energy metabolism. This review summarizes the recent knowledge about functions of Bcl-2 family proteins that are related to cell survival.
View Article and Find Full Text PDFEndometrial cancer is the most commonly diagnosed gynecological cancer and its incidence is increasing worldwide. The number of patients with this disease is likely to continue to grow, including younger patients. It is a complex disease driven by abnormal genetic and epigenetic alterations, as well as environmental factors.
View Article and Find Full Text PDFTumors of the brain are very diverse in their biological behavior and are therefore considered a major issue in modern medicine. The heterogeneity of gliomas, their clinical presentation and their responses to treatment makes this type of tumor a challenging area of research. Glioblastoma multiforme (GBM) is the most common, and biologically the most aggressive, primary brain tumor in adults.
View Article and Find Full Text PDFThe gene expression profile of breast cancer has been described as a great breakthrough on the way to comprehend differences in cancer origin, behavior and therapy. However, gene expression profile in histologically normal epithelium (HNEpi) which could harbor genetic abnormalities predisposing breast tissue to develop malignancy was minor scope for scientists in the past. Thus, we aimed to analyze gene expressions in HNEpi and breast cancer tissue (BCTis) in order to establish its value as potential diagnostic marker for cancer development.
View Article and Find Full Text PDFGene expression profile‑based taxonomy of breast cancer (BC) has been described as a significant breakthrough in comprehending the differences in the origin and behavior of cancer to allow individually tailored therapeutic approaches. In line with this, we hypothesized that the gene expression profile of histologically normal epithelium (HNEpi) could harbor certain genetic abnormalities predisposing breast tissue cells to develop human epidermal growth factor receptor 2 (HER2)‑positive BC. Thus, the aim of the present study was to assess gene expression in normal and BC tissue (BCTis) from patients with BC in order to establish its value as a potential diagnostic marker for cancer development.
View Article and Find Full Text PDFBortezomib (PS-341, or Velcade), reversible inhibitor of 20S proteasome approved for the treatment of multiple myeloma and mantle cell lymphoma, exhibited a cytotoxic effect toward other malignancies including leukaemia. In this study, we have documented that incubation of both HL-60 and K562 leukaemia cells with nanomolar concentrations of bortezomib is associated with the death of HL-60 cells observed within 24 hours of incubation with bortezomib and the death of K562 cells that were observed after 72 hours of incubation with bortezomib. The relative resistance of K562 cells to bortezomib correlated well with significantly higher expression of HSP27, HSP70, HSP90α, HSP90β and GRP75 in these cells.
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