thymine/neoplasms

Reaction of N3-benzoyl-1-[3,5-O-(tetraisopropyldisiloxan-1,3-diyl)-beta- D- ribofuranosyl]thymine (4a) with diphenyl phosphorazidate, diethyl azodicarboxylate, and triphenylphosphine in tetrahydrofuran afforded N3-benzoyl-1-[2-azido-2-deoxy-3,5-O-

Formation of ribothymidine by the ribose exchange reaction between thymine and uridine with the cell-free extract of mouse Ehrlich ascites tumor cells was demonstrated. Since phosphate ions appear to be not required for this reaction, perhaps it proceeds by the mechnism of direct exchange of

The rat fibroblast cell line Rat 1 was transfected with total DNA of a gastrocarcinoma cell line, BGC-823. The transforming gene was cloned from the genomic library of the secondary transformants using in situ hybridization with a probe of the human Alu repeat sequence. This cloned gene is

MGMT is the primary vehicle for cellular removal of alkyl lesions from the O-6 position of guanine and the O-4 position of thymine. While key to the maintenance of genomic integrity, MGMT also removes damage induced by alkylating chemotherapies, inhibiting the efficacy of cancer treatment. Germline

Alkylation of DNA at the 0(6) position of guanine is regarded as one o f the most critical events leading to induction of mutations and cancers in organisms. Once 0(6)-methylguanine is formed, it can pair with thymine during DNA replication, the result being a conversion of the guanine.cytosine to

Ultraviolet (UV) irradiation is a major mutagenic environmental agent, causing the appearance of DNA adducts that, if unrepaired, may give rise to mutations. Ultraviolet radiation has been indicated as a major risk factor in the development of nonmelanoma skin cancers; however, recent reports have

In recent years, there has been increasing interest in damaged DNA and RNA nucleobases. These damaged nucleobases can cause DNA mutation, resulting in various diseases such as cancer. Alkylating agents are mutagenic and carcinogenic in a variety of prokaryotic and eukaryotic organisms. The present

N-nitrosation of glycine and its derivatives generates potent alkylating agents that can lead to the formation of O(6)-carboxymethylguanine (O(6)-CMG) in DNA. O(6)-CMG has been identified in DNA derived from human colon tissue, and its occurrence has been linked to diets high in red and processed

The radioactivity of 14C-labeled 2'-fluoro-5-iodo-1-beta-D-arabinofuranosylcytosine ([2-14C]-FIAC), a new and potent antiherpetic agent, was shown previously to be incorporated into the DNA fractions of mammalian and neoplastic tissues. The present work was undertaken to learn the nature of the

Electron microscopic studies of sarcoma-180 ascites cells, which were treated with platinum-thymine at a concentration of 60 micrograms/ml, showed mitotic inhibition. The drug clumped the chromosomes into a compact mass at the center of the cell preventing them from separating during mitosis.

This work highlights the explosion and evolution of positron emission tomography (PET) for use in oncology research and clinical practice. 2-Deoxy-2-[F-18]fluoro-D-glucose (FDG)-PET is important in the staging of cancer, estimation of prognosis, and for its ability to predict therapeutic outcome. A

Thymidine phosphorylase (TP), an enzyme involved in the reversible conversion of thymidine to thymine, is identical to an angiogenic factor, platelet-derived endothelial cell growth factor (PD-ECGF). Both TP and one of the TP-degradation products of thymidine 2-deoxy-D-ribose (dRib) display

Tumour angiogenesis is a complex multistep process regulated by a number of angiogenic factors. One such factor, platelet-derived endothelial cell growth factor has recently been shown to be thymidine phosphorylase (TP). TP catalyses the reversible phosphorylation of thymidine to

Treatment of female SKH-1 hairless mice with ultraviolet B light twice a week for 20 weeks resulted in a population of tumor-free mice with a high risk of developing skin tumors during the next several months in the absence of additional UVB treatment (high-risk mice). Topical applications of

OBJECTIVE Inactivation of tumor suppressor and DNA repair genes by promoter hypermethylation does commonly occur in human cancers. O(6)-methylguanine-DNA methyltransferase (MGMT) is a DNA repair enzyme that removes methyl groups as well as larger adducts at the O(6) position of guanine. In the