Abstract:
:DNA topoisomerase II alpha is a nuclear enzyme essential for DNA metabolism and cell cycle progression. Previous studies have shown that human tumor cell lines can express more than one topoisomerase II alpha isoform through alternative splicing. A 160-kDa isoform of topoisomerase II alpha has been described in several cell lines selected for resistance to inhibitors of DNA topoisomerase, but its physiological function has not been defined. In the present study, we have identified two major (160 and 140 kDa) and two minor (150 and 145 kDa) isoforms of topoisomerase II alpha in drug-sensitive human leukemic CEM cells, all of which have lost C-terminal regions that produce epitopes recognized by specific antibodies. Reverse transcription-polymerase chain reaction and molecular cloning identified four alternatively spliced transcripts of topoisomerase II alpha from CEM cells. Furthermore, nucleotide sequencing indicated that the 160-kDa isoform is encoded by two transcripts derived from alternative splicing at a different C-terminal site and that the other two transcripts likely code for the 150-kDa isoform. Although the full-length topoisomerase II alpha resided in the cell nucleus, all altered isoforms, except the 160 kDa that was located in both cytoplasmic and nuclear extracts in about equal amount, were shown to be present predominantly in the cytosol. In contrast to the observations of other groups, we have not found an association of the topoisomerase II alpha isoforms with drug resistance. Rather, our results suggest that expression of topoisomerase II alpha isoforms is cell type specific or might be associated with the neoplastic phenotype of the cells. Thus, although T-lineage tumor cell lines examined (CEM, Jurkat, and H9) displayed altered topoisomerase II alpha isoforms, normal T cells expressed only a full-length copy of the gene. Together, these results suggest that expression of altered topoisomerase II alpha isoforms is not limited to drug resistance, but might be a feature of neoplastic cells.
journal_name
Oncol Resjournal_title
Oncology researchauthors
Mo YY,Beck WTsubject
Has Abstractpub_date
1997-01-01 00:00:00pages
193-204issue
4eissn
0965-0407issn
1555-3906journal_volume
9pub_type
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journal_title:Oncology research
pub_type: 杂志文章
doi:
更新日期:1995-01-01 00:00:00
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journal_title:Oncology research
pub_type: 杂志文章
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更新日期:1998-01-01 00:00:00
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journal_title:Oncology research
pub_type: 杂志文章
doi:
更新日期:1994-01-01 00:00:00
abstract::O6-Alkylguanine-DNA alkyltransferase (AGT) is a DNA repair protein that reverses alkylation damage produced by chloroethylnitrosoureas and is a major determinant of cellular resistance to adjuvant chemotherapy with these drugs. AGT activity was measured in 119 samples from 69 patients, including normal, tumor, and dis...
journal_title:Oncology research
pub_type: 杂志文章
doi:
更新日期:1997-01-01 00:00:00
abstract::Cervical cancer is one of the most common neoplastic diseases affecting women, with a combined worldwide incidence of almost half a million new cases. Considering the fact that IL-18 plays an important role in the interactions among T cells, NK cells, and macrophages and induces IFN-gamma production, efforts should be...
journal_title:Oncology research
pub_type: 杂志文章
doi:10.3727/096504008785114156
更新日期:2008-01-01 00:00:00
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journal_title:Oncology research
pub_type: 杂志文章
doi:10.3727/096504003773994815
更新日期:2004-01-01 00:00:00
abstract::Spinal osteosarcoma (OS) is a malignant tumor that has a poor outcome. MicroRNA-520b (miR-520b) acts as a cancer suppressor in various types of cancer. Because of the limited amount of literature on OS, we aimed to identify the role of miR-520b in OS. The miR-520b level in clinical spinal OS tissues and adjacent nontu...
journal_title:Oncology research
pub_type: 杂志文章
doi:10.3727/096504017X14873430389189
更新日期:2017-09-21 00:00:00
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journal_title:Oncology research
pub_type: 杂志文章,评审
doi:10.3727/096504010x12828372551867
更新日期:2010-01-01 00:00:00
abstract::Ubiquitin-specific protease 22 (USP22), a novel deubiquitinating enzyme, belongs to an extended family of proteins that have ubiquitin hydrolase activity. Recently, USP22 has attracted widespread attention because of its implication in carcinogenesis. However, there have been no studies, to our knowledge, investigatin...
journal_title:Oncology research
pub_type: 杂志文章
doi:10.3727/096504016X14772395226335
更新日期:2017-05-24 00:00:00
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journal_title:Oncology research
pub_type: 杂志文章
doi:10.3727/000000003108748612
更新日期:2003-01-01 00:00:00
abstract::All-trans-Retinoic acid (RA) induces differentiation and inhibits growth of many tumor types. Whereas the RA nuclear receptors mediate genomic effects of RA, there also are many nongenomic effects that do not have defined mechanisms. Some nongenomic effects of RA may involve retinoylation (RA acylation), a posttransla...
journal_title:Oncology research
pub_type: 杂志文章
doi:
更新日期:1997-01-01 00:00:00
abstract::MicroRNAs (miRNAs) are emerging as pivotal regulators in the development and progression of various cancers, including renal cell carcinoma (RCC). MicroRNA-384 (miR-384) has been found to be an important cancer-related miRNA in several types of cancers. However, the role of miR-384 in RCC remains unclear. In this stud...
journal_title:Oncology research
pub_type: 杂志文章
doi:10.3727/096504017X15035025554553
更新日期:2018-04-10 00:00:00
abstract::There is growing evidence on the clinical significance of Tumor Microenvironment (TME) cells in predicting prognosis and therapeutic effects. However, cell interactionsin tumor microenvironments have not been thoroughly studied or systematicallyanalyzed so far. In this study, 22 immune cell components in the lung aden...
journal_title:Oncology research
pub_type: 杂志文章
doi:10.3727/096504020X15907428281601
更新日期:2020-05-29 00:00:00
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journal_title:Oncology research
pub_type: 杂志文章
doi:10.3727/096504013X13854886566598
更新日期:2013-01-01 00:00:00
abstract::Accumulated studies have strongly implicated aberrantly expressed microRNAs (miRNAs) in carcinogenesis and cancer progression of various cancers, including colorectal cancer (CRC). Hence, a comprehensive study of miRNAs and their association with CRC may be a promising therapeutic method for patients with this maligna...
journal_title:Oncology research
pub_type: 杂志文章
doi:10.3727/096504018X15188747585738
更新日期:2018-10-17 00:00:00
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journal_title:Oncology research
pub_type: 杂志文章
doi:10.3727/096504017X15140544654946
更新日期:2018-08-23 00:00:00
abstract::Liver injury is often observed in various pathological conditions including posthepatectomy state and cancer chemotherapy. It occurs mainly as a consequence of the combined necrotic and apoptotic types of cell death. In order to study liver/hepatocyte injury by the necrotic type of cell death, we studied signal-regula...
journal_title:Oncology research
pub_type: 杂志文章
doi:10.3727/096504017X15005102445191
更新日期:2018-04-10 00:00:00
abstract::The human nucleolar protein p120 is highly expressed in human cancers. Its high expression in breast cancer correlates with a poor prognosis, and its overexpression in 3T3 mouse fibroblasts causes malignant transformation. This study reports that a combination of monoclonal anti-p 120 antibody (MAbp120), liposomes (Li...
journal_title:Oncology research
pub_type: 杂志文章
doi:
更新日期:1996-01-01 00:00:00
abstract::Cancer-associated fibroblasts (CAFs) play a predominant role in regulating tumor progression. Understanding how CAFs communicate with osteosarcoma is crucial for developing novel approaches for osteosarcoma therapy. Exosomes are able to transmit messages between cells. In this study, we demonstrated that CAFs transfer...
journal_title:Oncology research
pub_type: 杂志文章
doi:10.3727/096504018X15336368805108
更新日期:2019-09-23 00:00:00
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journal_title:Oncology research
pub_type: 杂志文章
doi:
更新日期:1996-01-01 00:00:00
abstract::Mutations in the APC gene contribute to development of sporadic desmoid tumors as well as to the hereditary tumors that usually accompany familial adenomatous polyposis (FAP). Adenomatous polyposis coli (APC) mutations cause an intracellular accumulation of beta-catenin that results in abnormal signaling in the wnt/wi...
journal_title:Oncology research
pub_type: 杂志文章
doi:
更新日期:1998-01-01 00:00:00
abstract::Kiss-1 has been identified as a putative metastasis suppressor gene in various human malignancies. However, there is little information about its possible role in gastric carcinoma. In this study, we determined whether the Kiss-1 gene negatively regulates MMP-9 expression. cDNA microarray technology was used to identi...
journal_title:Oncology research
pub_type: 杂志文章
doi:10.3727/096504009789954591
更新日期:2009-01-01 00:00:00
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journal_title:Oncology research
pub_type: 杂志文章,评审
doi:10.3727/096504008786111383
更新日期:2008-01-01 00:00:00
abstract::Recently, there has been significant effort in developing techniques designed to detect disseminated tumor cells in the peripheral blood (PB). These techniques include immunocytochemical staining of cytocentrifuge slides, flow cytometry, and RT-PCR. Several authors reported various results concerning the sensitivity o...
journal_title:Oncology research
pub_type: 杂志文章
doi:
更新日期:1999-01-01 00:00:00
abstract::PPAR-gamma is known to have a growth-suppressive effect in different cancers. In this study, we investigated the role of PPAR-gamma in the development of Barrett's esophagus (BE) and esophageal adenocarcinoma (EA). We used immunohistochemistry and real-time PCR to analyze differences in PPAR-gamma protein and mRNA exp...
journal_title:Oncology research
pub_type: 杂志文章
doi:10.3727/096504011x12935427587849
更新日期:2011-01-01 00:00:00
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journal_title:Oncology research
pub_type: 杂志文章
doi:
更新日期:1998-01-01 00:00:00
abstract::Lung cancer remains a critical health concern worldwide. Long noncoding RNAs with ultraconserved elements have recently been implicated in human tumorigenesis. The present study investigated the role of ultraconserved element 338 (uc.338) in the regulation of cell proliferation and metastasis in human lung cancer. Our...
journal_title:Oncology research
pub_type: 杂志文章
doi:10.3727/096504016X14666990347671
更新日期:2016-01-01 00:00:00
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journal_title:Oncology research
pub_type: 杂志文章
doi:
更新日期:1995-01-01 00:00:00
abstract::Gastric cancer (GC) is the most common epithelial malignancy worldwide. Basic transcription factor 3 (BTF3) plays a crucial role in the regulation of various biological processes. We designed experiments to investigate the molecular mechanism underlying the role of BTF3 in GC cell proliferation and metastasis. We conf...
journal_title:Oncology research
pub_type: 杂志文章
doi:10.3727/096504017X14886494526344
更新日期:2017-11-02 00:00:00
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journal_title:Oncology research
pub_type: 杂志文章
doi:
更新日期:1998-01-01 00:00:00