Search results for "Transform"
showing 10 items of 3975 documents
Cancer stem cell definitions and terminology:the devil is in the details
2012
The cancer stem cell (CSC) concept has important therapeutic implications, but its investigation has been hampered both by a lack of consistency in the terms used for these cells and by how they are defined. Evidence of their heterogeneous origins, frequencies and their genomic, as well as their phenotypic and functional, properties has added to the confusion and has fuelled new ideas and controversies. Participants in The Year 2011 Working Conference on CSCs met to review these issues and to propose a conceptual and practical framework for CSC terminology. More precise reporting of the parameters that are used to identify CSCs and to attribute responses to them is also recommended as key t…
Novel insulin receptor substrate 1 and 2 variants in breast and colorectal cancer
2013
The insulin/insulin-like growth factor pathway is involved in breast and colorectal cancer (CRC) development. In the present study, we analyzed the coding region and short intron-exon borders of the insulin receptor substrate 1 and 2 (IRS‑1 and IRS‑2) genes in 12 cell lines derived from breast cancer (BC), 14 cell lines derived from CRC and 33 primary CRCs. The nucleotide variants identified in BC were 3 in IRS‑1, 1 of which (p.Arg267Cys) was novel and with a pathogenic potential as predicted by in silico analysis and 6 in IRS‑2. Twenty‑one variants in IRS‑1 and 18 in IRS‑2 were identified in the CRC samples. These included 11 novel IRS‑1 variants detected exclusively in CRCs, which include…
Definitive evidence for Club cells as progenitors for mutantKras/Trp53‐deficient lung cancer
2021
Accumulating evidence suggests that both the nature of oncogenic lesions and the cell-of-origin can strongly influence cancer histopathology, tumor aggressiveness and response to therapy. Although oncogenic Kras expression and loss of Trp53 tumor suppressor gene function have been demonstrated to initiate murine lung adenocarcinomas (LUADs) in alveolar type II (AT2) cells, clear evidence that Club cells, representing the second major subset of lung epithelial cells, can also act as cells-of-origin for LUAD is lacking. Equally, the exact anatomic location of Club cells that are susceptible to Kras transformation and the resulting tumor histotype remains to be established. Here, we provide de…
STAT5 is crucial to maintain leukemic stem cells in acute myelogenous leukemias induced by MOZ-TIF2.
2012
Abstract MOZ-TIF2 is a leukemogenic fusion oncoprotein that confers self-renewal capability to hematopoietic progenitor cells and induces acute myelogenous leukemia (AML) with long latency in bone marrow transplantation assays. Here, we report that FLT3-ITD transforms hematopoietic cells in cooperation with MOZ-TIF2 in vitro and in vivo. Coexpression of FLT3-ITD confers growth factor independent survival/proliferation, shortens disease latency, and results in an increase in the number of leukemic stem cells (LSC). We show that STAT5, a major effector of aberrant FLT3-ITD signal transduction, is both necessary and sufficient for this cooperative effect. In addition, STAT5 signaling is essent…
Role of SHP2 for FLT3-dependent proliferation and transformation in 32D cells.
2008
Fms-like tyrosine kinase 3 (FLT3) is a class III receptor tyrosine kinase, which plays a role in proliferation and differentiation of B-cell progenitors, myelomonocytic and dendritic cells, as well as in the maintenance of pluripotent hematopoietic stem cells (reviewed in Stirewalt and Radich,1and Schmidt-Arras et al.2). Recently, FLT3 has received much attention as an important oncoprotein. Mutations in FLT3 that lead to constitutive activation are among the most common molecular lesions found in acute myeloid leukemia.3 The most prevalent type of mutations result in internal tandem duplications (ITD) of amino-acid stretches in the juxtamembrane domain of FLT3. FLT3-ITD is constitutively a…
Oligodendroglioma cells synthesize the differentiation-specific linker histone H1˚ and release it into the extracellular environment through shed ves…
2013
Chromatin remodelling can be involved in some of the epigenetic modifications found in tumor cells. One of the mechanisms at the basis of chromatin dynamics is likely to be synthesis and incorporation of replacement histone variants, such as the H1° linker histone. Regulation of the expression of this protein can thus be critical in tumorigenesis. In developing brain, H1° expression is mainly regulated at the post-transcriptional level and RNA-binding proteins (RBPs) are involved. In the past, attention mainly focused on the whole brain or isolated neurons and little information is available on H1° expression in other brain cells. Even less is known relating to tumor glial cells. In this st…
MLL-Rearranged Leukemia Is Dependent on Aberrant H3K79 Methylation by DOT1L
2011
SummaryThe histone 3 lysine 79 (H3K79) methyltransferase Dot1l has been implicated in the development of leukemias bearing translocations of the Mixed Lineage Leukemia (MLL) gene. We identified the MLL-fusion targets in an MLL-AF9 leukemia model, and conducted epigenetic profiling for H3K79me2, H3K4me3, H3K27me3, and H3K36me3 in hematopoietic progenitor and leukemia stem cells (LSCs). We found abnormal profiles only for H3K79me2 on MLL-AF9 fusion target loci in LSCs. Inactivation of Dot1l led to downregulation of direct MLL-AF9 targets and an MLL translocation-associated gene expression signature, whereas global gene expression remained largely unaffected. Suppression of MLL translocation-a…
Colorectal cancer-derived small extracellular vesicles induce TGFβ1-mediated epithelial to mesenchymal transition of hepatocytes
2023
Abstract Background Metastatic disease is the major cause of cancer-related deaths. Increasing evidence shows that primary tumor cells can promote metastasis by preparing the local microenvironment of distant organs, inducing the formation of the so-called “pre-metastatic niche”. In recent years, several studies have highlighted that among the tumor-derived molecular components active in pre-metastatic niche formation, small extracellular vesicles (sEVs) play a crucial role. Regarding liver metastasis, the ability of tumor-derived sEVs to affect the activities of non-parenchymal cells such as Kupffer cells and hepatic stellate cells is well described, while the effects on hepatocytes, the m…
Mast Cells Infiltrating Inflamed or Transformed Gut Alternatively Sustain Mucosal Healing or Tumor Growth.
2015
Abstract Mast cells (MC) are immune cells located next to the intestinal epithelium with regulatory function in maintaining the homeostasis of the mucosal barrier. We have investigated MC activities in colon inflammation and cancer in mice either wild-type (WT) or MC-deficient (KitW-sh) reconstituted or not with bone marrow-derived MCs. Colitis was chemically induced with dextran sodium sulfate (DSS). Tumors were induced by administering azoxymethane (AOM) intraperitoneally before DSS. Following DSS withdrawal, KitW-sh mice showed reduced weight gain and impaired tissue repair compared with their WT littermates or KitW-sh mice reconstituted with bone marrow-derived MCs. MCs were localized i…
Ha-rasVa112 but not p53Ser247 leads to a significant neoplastic transformation rate of the putative rat liver stem cells (oval cell)
1996
In order to test the controversially discussed hypothesis that oval cells are part of a liver stem cell compartment and can give rise to cholangiocellular as well as hepatocellular carcinomas in the course of liver carcinogenesis, we transfected an oval cell line established in our laboratory with an oncogenically activated genomic Ha-ras clone (pUC EJ 6.6), carrying a valine at position 12 instead of the wild-type glycine, or a rat p53 cDNA mutated by site-directed mutagenesis at codon 247, which corresponds to codon 249 in the human p53. This codon is of particular interest since it represents a mutation hotspot observed in hepatocellular carcinoma especially in regions with high aflatoxi…