Browsing by Subject "DNA damage"

Article

Application of topoisomerase assays in the evaluation of natural products as antitumor agents

Constantinou, Andreas I.; Salti, G. (1999)

Initially, DNA topoisomerase (topo) inhibitors found clinical applications as antibiotics and cancer chemotherapeutic agents. Recently, we demonstrated that plant flavonoids that inhibit mammalian topo I or topo II might ...

Article

Attenuation of drug-stimulated topoisomerase II-DNA cleavable complex formation in wild-type HL-60 cells treated with an intracellular calcium buffer is correlated with decreased cytotoxicity and site-specific hypophosphorylation of topoisomerase IIα

Aoyama, M.; Grabowski, D. R.; Dubyak, G. R.; Constantinou, Andreas I.; Rybicki, L. A.; Bukowski, R. M.; Ganapathi, M. K.; Hickson, I. D.; Ganapathi, R. (1998)

Topoisomerase II (topo II), an essential enzyme for cell viability, is also the target for clinically important anti-neoplastic agents that stimulate topo II-mediated DNA scission. The role of alterations in topo IIα ...

Article

Black cohosh (Cimicifuga racemosa L.) protects against menadione-induced DNA damage through scavenging of reactive oxygen species: Bioassay-directed isolation and characterization of active principles

Burdette, J. E.; Chen, S. -N; Lu, Z. -Z; Xu, H.; White, B. E. P.; Fabricant, D. S.; Liu, J.; Fong, H. H. S.; Farnsworth, N. R.; Constantinou, Andreas I.; Van Breemen, R. B.; Pezzuto, J. M.; Bolton, J. L. (2002)

The roots/rhizomes of Cimicifuga racemosa L. (Nutt.) (black cohosh) have traditionally been used to treat menopausal symptoms through an unknown mechanism of action. In an effort to determine if black cohosh had additional ...

Article

Deficiencies in the Fanconi Anemia DNA damage response pathway increase sensitivity to HPV-associated head and neck cancer

Park, J. W.; Pitot, H. C.; Strati, Katerina; Spardy, N.; Duensing, S.; Grompe, M.; Lambert, P. F. (2010)

Patients with the rare genetic disease, Fanconi anemia (FA), are highly susceptible to squamous cell carcinomas arising at multiple anatomic sites including the head and neck region. Human papillomaviruses (HPVs), particularly ...

Article

Evidence that a metabolilte of equine estrogens, 4-hydroxyequilenin, induces cellular transformation in vitro

Pisha, E.; Lui, X.; Constantinou, Andreas I.; Bolton, J. L. (2001)

Estrogen replacement therapy has been correlated with an increased risk of developing hormone-dependent cancers. 4-Hydroxyequilenin (4-OHEN) is a catechol metabolite of equilenin and equilin which are components of the ...

Article

Genistein induces apoptosis and topoisomerase II-mediated DNA breakage in colon cancer cells

Salti, G. I.; Grewal, S.; Mehta, R. R.; Das Gupta, T. K.; Boddie, A. W., Jr.; Constantinou, Andreas I. (2000)

The present study was undertaken to determine if (a) genistein induces topo II-mediated DNA damage in HT-29 colon cancer cells

Article

Identification of the factors responsible for the in vitro pro-oxidant and cytotoxic activities of the olive polyphenols oleuropein and hydroxytyrosol

Odiatou, Elena M.; Skaltsounis, Alexios Leandros; Constantinou, Andreas I. (2013)

The olive polyphenols oleuropein and hydroxytyrosol were reported recently to produce extracellular hydrogen peroxide (H2O2) under standard culture conditions. The precise factors responsible for this production and the ...

Article

Induction of DNA damage and caspase-independent programmed cell death by vitamin e

Constantinou, Constantina; Neophytou, Christiana M.; Vraka, Panayiota S.; Hyatt, John Anthony; Papas, Konstantinos A.; Constantinou, Andreas I. (2012)

Vitamin E comprises 8 functionally unique isoforms and may be a suitable candidate for the adjuvant treatment of prostate cancer. In this study, we examined the ability of 2 vitamin E isoforms [α-tocotrienol (γ-TT) and ...

Article

A metabolite of equine estrogens, 4-hydroxyequilenin, induces DNA damage and apoptosis in breast cancer cell lines

Chen, Y.; Liu, X.; Pisha, E.; Constantinou, Andreas I.; Hua, Y.; Shen, L.; Van Breemen, R. B.; Elguindi, E. C.; Blond, S. Y.; Zhang, Fengwangdong; Bolton, J. L. (2000)

Estrogen replacement therapy has been correlated with an increased risk of developing breast or endometrial cancer. 4-Hydroxyequilenin (4-OHEN) is a catechol metabolite of equilenin which is a minor component of the estrogen ...

Article

A p53-mediated DNA damage response limits reprogramming to ensure iPS cell genomic integrity

Marión, R. M.; Strati, Katerina; Li, H.; Murga, M.; Blanco, R.; Ortega, S.; Fernandez-Capetillo, O.; Serrano, M.; Blasco, M. A. (2009)

The reprogramming of differentiated cells to pluripotent cells (induced pluripotent stem (iPS) cells) is known to be an inefficient process. We recently reported that cells with short telomeres cannot be reprogrammed to ...

Article

Photoselected electron transfer pathways in DNA photolyase

Prytkova, T. R.; Beratan, David N.; Skourtis, Spiros S. (2007)

Cyclobutane dimer photolyases are proteins that bind to UV-damaged DNA containing cyclobutane pyrimidine dimer lesions. They repair these lesions by photo-induced electron transfer. The electron donor cofactor of a photolyase ...

Article

Photosynthesis from the protein's perspective

Skourtis, Spiros S.; Beratan, David N. (2007)

Article

The soy isoflavone daidzein improves the capacity of tamoxifen to prevent mammary tumours

Constantinou, Andreas I.; White, B. E. P.; Tonetti, D.; Yang, Y.; Liang, W.; Li, W.; Van Breemen, R. B. (2005)

The aim of this study was to determine how the efficacy of tamoxifen is affected when combined with soy isoflavones. To address this, female Sprague-Dawley rats were placed on diets supplemented with tamoxifen, genistein, ...