Search results for "Transform"
showing 10 items of 3975 documents
Oral microbiome in Proliferative Verrucous Leukoplakia exhibits loss of diversity and enrichment of pathogens.
2021
Abstract Objectives Oral microbiome plays an important role in oral diseases. Among them, proliferative verrucous leucoplakia (PVL) is an uncommon form of progressive multifocal leukoplakia with a worryingly rate of malignant transformation. Here, we aimed to characterize the oral microbiome of PVL patients and compare it with those of healthy controls. Material and methods Oral biopsies from ten PVL patients and five healthy individuals were obtained and used to compare their microbial communities. The sequence of the V3-V4 region of 16S rRNA gene was used as the taxonomic basis to estimate and analyze the composition and diversity of bacterial populations present in the samples. Results O…
Abstract 3512: MYCN and survivin cooperatively contribute to malignant transformation of fibroblasts
2014
Abstract The oncogenes MYCN and survivin (BIRC5) maintain aggressiveness of diverse cancers including sarcomas. To investigate whether these oncogenes cooperate in initial malignant transformation, we transduced them into Rat-1 fibroblasts. Indeed, survivin enhanced MYCN-driven contact-uninhibited and anchorage-independent growth in vitro. Importantly, upon subcutaneous transplantation into mice, cells overexpressing both instead of either one of the oncogenes generated tumors with shortened latency, marked anaplasia and an increased proliferation-to-apoptosis ratio resulting in accelerated growth. Mechanistically, the increased tumorigenicity was associated with an enhanced Warburg effect …
Tumor Hypoxia: Causative Factors, Compensatory Mechanisms, and Cellular Response
2004
Abstract Learning Objectives After completing this course, the reader will be able to: Explain the effect of hypoxia on resistance to treatment. Describe the causes of tumor hypoxia. Characterize cellular response to hypoxia. Access and take the CME test online and receive 1 hour of AMA PRA category 1 credit at CME.TheOncologist.com Hypoxia is a characteristic feature of locally advanced solid tumors resulting from an imbalance between oxygen (O2) supply and consumption. Major causative factors of tumor hypoxia are abnormal structure and function of the microvessels supplying the tumor, increased diffusion distances between the nutritive blood vessels and the tumor cells, and reduced O2 tra…
Ionizing radiation but not anticancer drugs causes cell cycle arrest and failure to activate the mitochondrial death pathway in MCF-7 breast carcinom…
2001
There is considerable evidence that ionizing radiation (IR) and chemotherapeutic drugs mediate apoptosis through the intrinsic death pathway via the release of mitochondrial cytochrome c and activation of caspases -9 and -3. Here we show that MCF-7 cells that lack caspase-3 undergo a caspase-dependent apoptotic cell death in the absence of DNA fragmentation and alpha-fodrin cleavage following treatment with etoposide or doxorubicin, but not after exposure to IR. Re-expression of caspase-3 restored DNA fragmentation and alpha-fodrin cleavage following drug treatment, but it did not alter the radiation-resistant phenotype of these cells. In contrast to the anticancer drugs, IR failed to induc…
The human Lgl polarity gene, Hugl-2, induces MET and suppresses Snail tumorigenesis
2012
Lethal giant larvae proteins have key roles in regulating polarity in a variety of cell types and function as tumour suppressors. A transcriptional programme initiated by aberrant Snail expression transforms epithelial cells to potentially aggressive cancer cells. Although progress in defining the molecular determinants of this programme has been made, we have little knowledge as to how the Snail-induced phenotype can be suppressed. In our studies we identified the human lethal giant larvae homologue 2, Hugl-2, (Llgl2/Lgl2) polarity gene as downregulated by Snail. Snail binds E-boxes in the Hugl-2 promoter and represses Hugl-2 expression, whereas removal of the E-boxes releases Hugl-2 from …
Mitochondrial chaperones in cancer: From molecular biology to clinical diagnostics
2006
Mitochondria are cell organelles involved in processes of cell life and death, and therefore also in tumoral transformation. Indeed, mitochondria dysfunction is a prominent feature of cancer cells. Mitochondrial proteins and DNA have also been previously studied as markers of tumorigenesis. Heat shock proteins (HSPs) are ubiquitous evolutionary conserved proteins. HSPs enhance their expression in stressed cells and they are involved in gene expression regulation, DNA replication, signal transduction, differentiation, apoptosis, cellular senescence or immortalization. This review reflects recent views on the role of some mitochondrial molecular chaperones as prohibitin, mortalin and HSP60/HS…
Cytokines in cancer therapy
1989
The treatment options for patients with cancer are presently limited to surgical and radiotherapeutic strategies for localized disease and the systemic use of cytotoxic drugs for disseminated disease. So far, chemotherapy remains the mainstay for the treatment of metastatic cancer. Treatment results, however, have been stagnant particularly for the more frequent cancers such as lung cancer, breast cancer and colorectal cancer. Current research is seeking new concepts of cancer treatment, based upon a more profound understanding of tumor cell biology. The oncogenetic defect in neoplastic cells is a genetic alteration in a primordial cancer cell, which subsequently leads to clonal expansion a…
Coordinate mutation and transformation of mouse fibroblasts: induction by nitroquinoline oxide and modulation by caffeine
1981
Mutation and malignant transformation were followed in the same cells. Mouse fibroblasts (C3H 10T 1/2) were mutated and transformed by 4-nitroquinoline-1-oxide with similar, approximately linear dose-responses. The presence of caffeine immediately after exposure to 4-nitroquinoline-1-oxide potently inhibited mutation and transformation at high but not at low doses of 4-nitroquinoline-1-oxide. Whilst the coordinate induction of mutation and transformation could be explained by both a common target (DNA) or a common reactive species hitting several targets, the identical modulation by a DNA repair inhibitor of both end points suggests fundamental similarities in the nature of the lesions lead…
Apoptotic induction in transformed follicular lymphoma cells by Bcl-2 downregulation.
1998
The roles of Bcl-2 protein and the protein ratio of Bcl-2/Bax in regulating cell growth in various lymphoma cell lines were examined. A dose-dependent decrease in Bcl-2 protein expression was observed in the different lymphomas incubated with lipid-incorporated bcl-2 antisense oligonucleotides (L-bcl-2). Growth inhibition was observed in a transformed follicular lymphoma (FL) cell line, which has the t(14;18) translocation and Bcl-2 protein overexpression. One of the mechanisms by which L-bcl-2 growth inhibition is mediated in these transformed FL cells might be through apoptotic induction, because the treated cells had an increased apoptotic index and showed the typical DNA fragmentation. …
A placenta-specific gene ectopically activated in many human cancers is essentially involved in malignant cell processes.
2007
Abstract The identification and functional characterization of tumor-specific genes is a prerequisite for the development of targeted cancer therapies. Using an integrated data mining and experimental validation approach for the discovery of new targets for antibody therapy of cancer, we identified PLAC1. PLAC1 is a placenta-specific gene with no detectable expression in any other normal human tissue. However, it is frequently aberrantly activated and highly expressed in a variety of tumor types, in particular breast cancer. RNAi-mediated silencing of PLAC1 in MCF-7 and BT-549 breast cancer cells profoundly impairs motility, migration, and invasion and induces a G1-S cell cycle block with n…