Search results for "AC133 Antigen"
showing 10 items of 19 documents
Identification and expansion of human colon-cancer-initiating cells
2007
Colon carcinoma is the second most common cause of death from cancer. The isolation and characterization of tumorigenic colon cancer cells may help to devise novel diagnostic and therapeutic procedures. Although there is increasing evidence that a rare population of undifferentiated cells is responsible for tumour formation and maintenance, this has not been explored for colorectal cancer. Here, we show that tumorigenic cells in colon cancer are included in the high-density CD133+ population, which accounts for about 2.5% of the tumour cells. Subcutaneous injection of colon cancer CD133+ cells readily reproduced the original tumour in immunodeficient mice, whereas CD133- cells did not form …
Hemopoietic and angiogenetic progenitors in healthy athletes: different responses to endurance and maximal exercise
2010
J Appl Physiol. 2010 Jul;109(1):60-7. Epub 2010 May 6. Hemopoietic and angiogenetic progenitors in healthy athletes: different responses to endurance and maximal exercise. Bonsignore MR, Morici G, Riccioni R, Huertas A, Petrucci E, Veca M, Mariani G, Bonanno A, Chimenti L, Gioia M, Palange P, Testa U. SourceBiomedical Department, Internal and Specialistic Medicine (DIBIMIS), Section of Pneumology, University of Palermo, Via Trabucco, 180, 90146 Palermo, Italy. marisa@ibim.cnr.it Abstract The effects of endurance or maximal exercise on mobilization of bone marrow-derived hemopoietic and angiogenetic progenitors in healthy subjects are poorly defined. In 10 healthy amateur runners, we collect…
The AC133 epitope, but not the CD133 protein, is lost upon cancer stem cell differentiation.
2010
Abstract Colon cancer stem cells (CSC) can be identified with AC133, an antibody that detects an epitope on CD133. However, recent evidence suggests that expression of CD133 is not restricted to CSCs, but is also expressed on differentiated tumor cells. Intriguingly, we observed that detection of the AC133 epitope on the cell surface decreased upon differentiation of CSC in a manner that correlated with loss of clonogenicity. However, this event did not coincide with a change in CD133 promoter activity, mRNA, splice variant, protein expression, or even cell surface expression of CD133. In contrast, we noted that with CSC differentiation, a change occured in CD133 glycosylation. Thus, AC133 …
Therapeutic implications of Cancer Initiating Cells.
2009
Background: Until few years ago, all neoplastic cells within a tumour were suggested to have tumorigenic capacity, but recent evidences hint to the possibility that such feature is confined to a subset of Cancer Initiating Cells (CICs), also called Cancer Stem Cells (CSCs). These cells are the reservoir of the heterogeneous populations of differentiated cancer cells constituting the tumour bulk. Mechanisms shared with somatic stem cells, such as quiescence, self-renewal ability, asymmetric division and multidrug resistance, allow to these cells to drive tumour growth and to evade conventional therapy. Objective: Here, we give a brief overview on the origin of CICs, the mechanisms involved i…
Proliferation state and polo-like kinase1 dependence of tumorigenic colon cancer cells.
2012
Abstract Tumor-initiating cells are responsible for tumor maintenance and relapse in solid and hematologic cancers. Although tumor-initiating cells were initially believed to be mainly quiescent, rapidly proliferating tumorigenic cells were found in breast cancer. In colon cancer, the proliferative activity of the tumorigenic population has not been defined, although it represents an essential parameter for the development of more effective therapeutic strategies. Here, we show that tumorigenic colon cancer cells can be found in a rapidly proliferating state in vitro and in vivo, both in human tumors and mouse xenografts. Inhibitors of polo-like kinase1 (Plk1), a mitotic kinase essential fo…
CD133 Expression Is Not Synonymous to Immunoreactivity for AC133 and Fluctuates throughout the Cell Cycle in Glioma Stem-Like Cells.
2015
A transmembrane protein CD133 has been implicated as a marker of stem-like glioma cells and predictor for therapeutic response in malignant brain tumours. CD133 expression is commonly evaluated by using antibodies specific for the AC133 epitope located in one of the extracellular domains of membrane-bound CD133. There is conflicting evidence regarding the significance of the AC133 epitope as a marker for identifying stem-like glioma cells and predicting the degree of malignancy in glioma cells. The reasons for discrepant results between different studies addressing the role of CD133/AC133 in gliomas are unclear. A possible source for controversies about CD133/AC133 is the widespread assumpt…
Podoplanin discriminates distinct stromal cell populations and a novel progenitor subset in the liver
2015
Podoplanin/gp38+ stromal cells present in lymphoid organs play a central role in the formation and reorganization of the extracellular matrix and in the functional regulation of immune responses. Gp38+ cells are present during embryogenesis and in human livers of primary biliary cirrhosis. Since little is known about their function, we studied gp38+ cells during chronic liver inflammation in models of biliary and parenchymal liver fibrosis and steatohepatitis. Gp38+ cells were analyzed using flow cytometry and confocal microscopy, and the expression of their steady state and inflammation-associated genes was evaluated from healthy and inflamed livers. Gp38+ cells significantly expanded in …
Co-expression of CD133+/CD44+in human colon cancer and liver metastasis
2013
Although relatively good therapeutic results are achieved in non-advanced cancer, the prognosis of the advanced colon cancer still remains poor, dependent on local or distant recurrence of the disease. One of the factors responsible for recurrence is supposed to be cancer stem cells (CSCs) or tumor-initiating cells, which are a population of cancer cells with ability to perpetuate themselves through self-renewal and to generate differentiated cells, thought to be responsible for tumor recurrence. This study globally approach the possible role of tissue-derived stem cells in the initiation of colon cancer and its metastatic process in the liver. Fresh surgical specimens from colon cancer, no…
Colon Cancer Stem Cells Dictate Tumor Growth and Resist Cell Death by Production of Interleukin-4
2007
A novel paradigm in tumor biology suggests that cancer growth is driven by stem-like cells within a tumor. Here, we describe the identification and characterization of such cells from colon carcinomas using the stem cell marker CD133 that accounts around 2% of the cells in human colon cancer. The CD133(+) cells grow in vitro as undifferentiated tumor spheroids, and they are both necessary and sufficient to initiate tumor growth in immunodeficient mice. Xenografts resemble the original human tumor maintaining the rare subpopulation of tumorigenic CD133(+) cells. Further analysis revealed that the CD133(+) cells produce and utilize IL-4 to protect themselves from apoptosis. Consistently, trea…
Bone morphogenetic protein 4 induces differentiation of colorectal cancer stem cells and increases their response to chemotherapy in mice.
2010
BACKGROUND & AIMS: The limited clinical response observed in many patients with colorectal cancer may be related to the presence of chemoresistant colorectal can- cer stem cells (CRC-SCs). Bone morphogenetic protein 4 (BMP4) promotes the differentiation of normal colonic stem cells. We investigated whether BMP4 might be used to induce differentiation of CRC-SCs and for therapeutic purposes. METHODS: CRC-SCs were isolated from 25 tumor samples based on expression of CD133 or using a selection culture medium. BMP4 expression and activity on CRC-SCs were evaluated in vitro; progeny of the stem cells were evaluated by immunofluorescence, immuno- blot, and flow cytometry analyses. The potential …