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Basse B - - 2010
OBJECTIVES: Tumour cells respond to ionizing radiation by cycle arrest, cell death or repair and possible regrowth. We have developed a dynamic mathematical model of the cell cycle to incorporate transition probabilities for entry into DNA replication and mitosis. In this study, we used the model to analyse effects of ...
Qu Yaming - - 2010
Failure to control nasopharyngeal carcinomas (NPC) is mainly due to a portion of radioresistant phenotype. Identifying gene targets for radiosensitization is an important strategy in improving anticancer treatments. Exposure of cells to ionizing radiation leads to the formation of reactive oxygen species that are associated with radiation-induced cellular apoptosis and ...
Chiu Shu-Jun - - 2010
Combined-modality treatment has improved the outcome in cases of various solid tumors, and radiosensitizers are used to enhance the radiotherapeutic efficiency. Rosiglitazone, a synthetic ligand of peroxisome proliferator-activated receptors gamma used in the treatment of type-2 diabetes, has been shown to reduce tumor growth and metastasis in human cancer cells, ...
Lau Patrick - - 2010
Radiation response of bone cells, especially the bone-forming osteoblasts, is an important issue for radiotherapy in young age. A radiation-induced cell cycle arrest may enhance or accelerate osteoblastic differentiation. To analyze radiation response of osteoblastic cells, the correlation between DNA double-strand break induction (DSB), cell cycle alterations and gene expression ...
Guijin He - - 2011
To investigate the effect of (103)Pd radioactive stent on Caspase-9, cholangiocarcinoma cell growth and its radiosensitivity. Cholangiocarcinoma was treated with (103)Pd radioactive stent at different period. Radiosensitivity of the cells was detected by methyl thiazolyl tetrazolium (MTT) method. Apoptosis of cholangiocarcinoma cells was detected by immunohistochemistry and electron microscope. The ...
Trémezaygues Lea - - 2010
We investigated the capacity of 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) to protect spontaneously immortalized human keratinocytes (HaCaT) and cutaneous squamous cell carcinoma cells (SCL-1) against the hazardous effects of ionizing radiation (IR). We pretreated HaCaT and SCL-1 cells in vitro with 1,25(OH)2D3 (10(-7) M) over 48 h and then irradiated them once ...
Gavrilov Vladimir - - 2010
Radiotherapy is one of the curative treatment options for prostate cancer (PCa). However, effective doses of ionizing radiation (IR) have a high risk of side effects. To increase sensitivity of PCa to IR we pretreated human androgen-refractory DU145 PCa cells with a combination of sodium valproate (VPA), a well-tolerated drug ...
Heo Soo-Jin - - 2010
In this study, potential inhibitory effect of 21 species of marine algae on melanogenesis was assessed via tyrosinase inhibitory effect. The Ishige okamurae extract tested herein evidenced profound tyrosinase inhibitory effect, compared to that exhibited by other marine algae extracts. Thus, I. okamurae was selected for use in further experiments, ...
Liu Junye - - 2010
Hypoxia inducible factor 1 (HIF-1), the key mediator of hypoxia signaling pathways, has been shown involved in hypoxia-induced radioresistance. However, the underlying mechanisms are unclear. The present study demonstrated that both hypoxia and hypoxia mimetic cobalt chloride could increase the radioresistance of human cervical cancer Hela cells. Meanwhile, ectopic expression ...
Tomita Masanori - - 2010
Abstract The radiation-induced bystander response is defined as a response in cells that have not been directly targeted by radiation but that are in the neighborhood of cells that have been directly exposed. In the work described here, it is shown that bystander cell killing of normal human fibroblast WI-38 ...
El-Awady Raafat A - - 2010
Inhibition of the repair of 5-fluorouracil (FU)-induced DNA lesions may improve the response of many tumors to this anticancer agent. Despite the identified associations between DNA strand breaks and the lethality of thymidylate synthase inhibitors, the role of DNA double-strand break (DSB) repair pathways in a cellular response to 5-FU ...
Qian Liren - - 2010
It has been demonstrated that hydrogen can selectively reduce hydroxyl and peroxynitrite in vitro. Since most of the ionizing radiation-induced cellular damage is caused by hydroxyl radicals, this study was designed to test the hypothesis that hydrogen may be an effective radioprotective agent. This paper demonstrates that treating cells with ...
Huang Ge - - 2010
A novel camptothecin derivative (TLC388) with higher efficacy and reduced toxicity has been synthesized and tested as a novel chemoradiosensitizing agent. This study investigated the mechanisms of the chemoradiosensitizing effects of TLC388 on H23 human non-small cell lung cancer (NSCLC) cells. Using the TUNEL assay, a significantly higher percentage of ...
Yin Xiaoying - - 2010
Heat shock protein 90 (Hsp90) is a molecular chaperone that promotes the conformational maturation of numerous client proteins, many of which play critical roles in tumor cell growth and survival. The ansamycin-based Hsp90 inhibitor 17-allylamino-17-demethoxygeldanamycin (17-AAG) is currently in Phase III clinical testing. However, 17-AAG is difficult to formulate and ...
Chen Chang-Ming - - 2010
To examine the role of DNA repair and altered thymidine analogues in altering the response to radiation during thymidine deprivation. Mismatch repair-deficient and -proficient cell lines HEC59 and HC-2.4 were treated with fluorodeoxyuridine (FUdR), azidothymidine (AZT), and irradiation either alone or in combination, and outcomes of clonogenic survival and cell-cycle ...
McArt Darragh G - - 2010
The comet assay is a sensitive tool for estimation of DNA damage and repair at the cellular level, requiring only a very small number of cells. In comparing the levels of damage or repair in different cell samples, it is possible that small experimental effects could be confounded by different ...
Javvadi Prashanthi P Department of Cancer Biology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104, - - 2010
Curcumin, a plant polyphenol, is a widely studied chemopreventive agent with demonstrated antitumor activities in preclinical studies and low toxicity profiles in multiple clinical trials against human malignancies. We previously showed that curcumin radiosensitizes cervical tumor cells without increasing the cytotoxic effects of radiation on normal human fibroblasts. Here we ...
Costantini Danny L - - 2010
Our goal in this study was to elucidate the mechanisms by which methotrexate radiosensitizes HER2-positive human breast cancer cells to the Auger electron emitter (111)In-trastuzumab modified with nuclear-localization sequence peptides ((111)In-NLS-trastuzumab) and to compare these mechanisms with the potential sensitizing effects of paclitaxel and doxorubicin when combined with this radiopharmaceutical. ...
Boboila Cristian C Department of Genetics, Harvard Medical School, Boston, MA 02115, - - 2010
The classical nonhomologous end-joining (C-NHEJ) DNA double-strand break (DSB) repair pathway employs the Ku70/80 complex (Ku) for DSB recognition and the XRCC4/DNA ligase 4 (Lig4) complex for ligation. During IgH class switch recombination (CSR) in B lymphocytes, switch (S) region DSBs are joined by C-NHEJ to form junctions either with ...
Torres Mylin A - - 2011
The present study investigated the effect of AC480, a small molecule pan-HER tyrosine kinase inhibitor, on in vitro radiosensitivity and in vivo radioresponse of a human head and neck squamous cell carcinoma cell line. HN-5 cells were exposed to γ-radiation with and without AC480 and assayed for proliferation, clonogenic survival, ...
Williamson Chris T - - 2010
Poly(ADP-ribose) polymerase-1 (PARP-1) inhibition is toxic to cells with mutations in the breast and ovarian cancer susceptibility genes BRCA1 or BRCA2, a concept termed synthetic lethality. However, whether this approach is applicable to other human cancers with defects in other DNA repair genes has yet to be determined. The ataxia ...
Dziegielewski Jaroslaw J Department of Radiation Oncology, Radiation Oncology Research Laboratory, University of Maryland School of Medicine, Baltimore, Maryland, - - 2010
Repair of DNA damage through homologous recombination (HR) pathways plays a crucial role in maintaining genome stability. However, overstimulation of HR pathways in response to genotoxic stress may abnormally elevate recombination frequencies, leading to increased mutation rates and delayed genomic instability. Radiation-induced genomic instability has been detected after exposure to ...
Sinn Brigitte - - 2010
PTEN mutations are frequently found in malignant glioma and can result in activated phosphatidylinositol-3-kinase/Akt survival signaling associated with resistance to radiotherapy. Strategies to interfere with aberrant PI3K/Akt activity are therefore being developed to improve the therapeutic efficacy of radiotherapy in patients with malignant glioma. The methylxanthine caffeine has been described ...
Wright Eric G - - 2010
A well-established radiobiological paradigm is that the biological effects of ionizing radiation occur in irradiated cells as a consequence of the DNA damage they incur. However, many observations of, so-called, non-targeted effects indicate that genetic alterations are not restricted to directly irradiated cells. Non-targeted effects are responses exhibited by non-irradiated ...
Kim Eun Jin - - 2010
TSPYL5, encoding testis-specific Y-like protein, has been postulated to be a tumor suppressor gene, and its hypermethylation is often associated with human disease, especially cancer. In this study, we report that the TSPYL5 gene was less methylated (30%) in A549 lung adenocarcinoma cells, which are relatively resistant to gamma-radiation, than ...
Suzuki Keiji - - 2010
Ionizing radiation induces delayed destabilization of the genome in the progenies of surviving cells. This phenomenon, which is called radiation-induced genomic instability, is manifested by delayed induction of radiation effects, such as cell death, chromosome aberration, and mutation in the progeny of cells surviving radiation exposure. Previously, there was a ...
Fleisig Helen B - - 2010
Transient expression of adenoviral oncoprotein E1B55K in normal cells induces aggresome formation and sequestration of critical host proteins in aggresomes. Our previous studies reported that Sequence Specific Binding Protein 2 (SSBP2), a candidate tumor suppressor is recruited to aggresomes in adenovirally transformed human embryonal kidney 293 (HEK293) cells. To understand ...
Soule Benjamin P - - 2010
BACKGROUND: The histamine receptor-1 (H1)-antagonist, loratadine has been shown to inhibit growth of human colon cancer xenografts in part due to cell cycle arrest in G2/M. Since this is a radiation sensitive phase of the cell cycle, we sought to determine if loratadine modifies radiosensitivity in several human tumor cell ...
Di Girolamo Nick - - 2010
The eye and the skin are protected by a multi-layered epithelial barrier that provides the first line of defence against invading pathogens and environmental stresses such as damaging solar ultraviolet radiation. Extensive epidemiological findings supported by compelling experimental evidence in culture and animal models suggest that ultraviolet radiation is the ...
Kim In Ah - - 2010
Histone deacetylase inhibitors (HDIs) have attracted considerable attention for anticancer therapy strategy, including radiosensitization. Regarding a potential application of HDI as a radiosensitizer in the treatment of solid tumors, an important question is whether treatment efficacy would be influenced by intrinsic differences between cancer cells, such as different histologic origin ...
He Hai-Tao - - 2010
Siah proteins play an important role in cancer progression. We evaluated the effect of Siah1, its splice variants Siah1L and the Siah1 mutant with the RING finger deleted (Siah1DeltaR) on radiosensitization of human breast cancer cells. The status of Siah1 and Siah1L was analysed in five breast cancer cell lines. ...
Kikawa Keith D - - 2010
Both ionizing radiation and docosahexaenoic acid (DHA), an n-3 polyunsaturated fatty acid (PUFA), have been shown to inhibit tumor cell growth at least in part by increasing oxidative stress. In this study, the effects of ionizing radiation, DHA, or a combination of the two on cell proliferation, anchorage-independent growth, apoptosis, ...
Kuribayashi Takeshi - - 2010
A group of histone deacetylase (HDAC) inhibitors has been shown to suppress the growth of a variety of human tumor lines in vitro and in vivo and they are among the most promising candidates for anti-cancer therapeutic agents. We investigated the ability of scriptaid, a novel HDAC inhibitor and trichostatin ...
Kuwahara Yoshikazu - - 2010
The high-density survival (HDS) assay was originally elaborated to assess cancer cell responses to therapeutic agents under the influence of intercellular communication. Here, we simplified the original HDS assay and studied its applicability for the detection of cellular radioresistance. We have recently defined clinically relevant radioresistant (CRR) cells, which continue ...
Liu Feng - - 2010
As a survival factor for melanocytes lineage cells, MiTF plays multiple roles in development and melanomagenesis. What role MiTF plays in the DNA damage response is currently unknown. In this report we observed that MiTF was phosphorylated at serine 73 after UVC radiation, which was followed by proteasome-mediated degradation. Unlike ...
Naidu Mamta D - - 2010
Since radiation therapy remains a primary treatment modality for gliomas, the radioresistance of glioma cells and targets to modify their radiation tolerance are of significant interest. Human apurinic endonuclease 1 (Ape1, Ref-1, APEX, HAP1, AP endo) is a multifunctional protein involved in base excision repair of DNA and a redox-dependent ...
Purrucker Jan C - - 2010
HDAC inhibitors (HDACi) are gaining increasing attention in the treatment of cancer, particularly in view of their therapeutic effectiveness and assumed mild toxicity profile. While numerous studies have investigated the role of HDACi in tumor cells, little is known about their effects on normal tissue cells. We studied the effect ...
Sharma Ved Parkash - - 2010
The indiscriminate use of wireless technologies, particularly of cell phones, has increased the health risks among living organisms including plants. We investigated the impact of cell phone electromagentic field (EMF) radiations (power density, 8.55 microW cm(-2)) on germination, early growth, proteins and carbohydrate contents, and activities of some enzymes in ...
Rockwell Sara - - 2010
Aplidin (plitidespin) is a novel cyclic depsipeptide, currently in Phase II clinical trials for solid and hematologic malignancies. We examined the effects of oxygen on the cytotoxicity of Aplidin and the interactions between Aplidin and radiation. These factors will be important if Aplidin is used clinically in combination with radiotherapy. ...
Park Soo-Yeon - - 2010
Inhibitors of epidermal growth factor receptor (EGFR) have shown dramatic results in a subset of patients with non-small cell lung cancer (NSCLC), and have also been shown to enhance the effect of ionizing radiation (IR). We investigated how gefitinib, an orally given EGFR inhibitor for NSCLC patients, can radiosensitize NSCLC ...
Kessler Jacqueline - - 2010
Hypoxia induces activation of the HIF-1 pathway and is an essential characteristic of malignant gliomas. Hypoxia has been linked to tumor progression, therapy resistance and poor prognosis. However, little is known about the impact of HIF-1α inhibition on radioresistance of malignant glioma. In this study, we investigated the effects of ...
Jiang Ping - - 2010
The microRNA-17-92 (miRNA-17-92) cluster, at chromosome 13q31-q32, also known as oncomir-1, consists of seven miRNAs that are transcribed as a polycistronic unit. Over-expression of miRNA-17-92 has been observed in lymphomas and other solid tumors. Whether miRNA-17-92 expression affects the response of tumor cells to radiotherapy is not addressed so far. ...
Baskar Rajamanickam R Department of Radiation Oncology, Division of Cellular and Molecular Research, National Cancer Centre, Singapore. - - 2010
Ionizing radiation is an invaluable diagnostic and treatment tool used in various clinical applications. On the other hand, radiation is a known cytotoxic with a potential DNA damaging and carcinogenic effects. However, the biological effects of low and high linear energy transfer (LET) radiations are considerably more complex than previously ...
Luzhna Lidia - - 2010
Chemoresistant tumors often fail to respond to other cytotoxic treatments such as radiation therapy. The mechanisms of chemo- and radiotherapy cross resistance are not fully understood and are believed to be epigenetic in nature. We hypothesize that MCF-7 cells and their doxorubicin-resistant variant MCF-7/DOX cells may exhibit different responses to ...
Riesterer Oliver - - 2011
Check point kinases (Chk) play a major role in facilitating DNA repair upon radiation exposure. We tested the potency of a novel inhibitor of Chk1 and Chk2, XL-844 (provided by Exelixis Inc., CA, USA), to radiosensitize human cancer cells grown in culture and investigated the underlying mechanisms. HT-29 cells (a ...
Lin Chi-Iou - - 2009
BACKGROUND: Autophagy is a conserved response to stress that facilitates cell survival in some contexts and promotes cell death in others. We sought to characterize autophagy in papillary thyroid cancer (PTC), and to determine the effects of autophagy inhibition on chemosensitivity and radiosensitivity. METHODS: The human thyroid papillary carcinoma cell ...
Hidaka Masayuki - - 2010
It was reported that the radiation-sensitive Medaka mutant "ric1" has a defect in the repair of DNA double-strand breaks (DSBs) induced by gamma-rays during early embryogenesis. To study the cellular response of a ric1 mutant to ionizing radiation (IR), we established the mutant embryonic cell lines RIC1-e9, RIC1-e42, RIC1-e43. Following ...
Liu Shuang - - 2009
Matrix extracellular phosphoglycoprotein/osteoblast factor 45 (MEPE/OF45) was cloned in 2000 with functions related to bone metabolism. We identified MEPE/OF45 for the first time as a new co-factor of CHK1 in mammalian cells to protect cells from DNA damage induced killing. We demonstrate here that MEPE/OF45 directly interacts with CHK1. Knocking ...
Hawkins Roland B - - 2009
The relationship between relative biological effectiveness in the limit of zero dose (RBE(1)) and the LET of radiation is examined and compared for several cell lines, including cells from patients with ataxia telangiectasia, in the context of a microdosimetric-kinetic (MK) model of cell killing by radiation. Evidence is presented that ...
No Mina - - 2009
Several studies have indicated the potential value of targeting HER-2 signaling to enhance the anti-tumor activity of ionizing radiation. However, therapeutic resistance resulting from several factors, including activation of the downstream pathway, represents a major obstacle to treatment. Here, we investigated whether inhibitors targeting downstream of HER-2 signaling would radiosensitize ...
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