Herpes simplex virus type 1 (HSV) thymidine kinase (TK) has been widely used in suicide gene therapy for the treatment of cancer due to its broad substrate specificity and the inability of the endogenous human TK to phosphorylate guanosine analogs such as ganciclovir (GCV). The basis of suicide gene therapy is the introduction of a gene that encodes a prodrug-activating enzyme into tumor cells....

Thyroid carcinoma accounts for the majority of deaths from endocrine cancers. Although effective therapies exist for well differentiated tumors, the treatment options for poorly differentiated and anaplastic tumors are much less effective. In the present study we demonstrate that the thyroglobulin (Tg) promoter can be used to direct specific expression of either luciferase or thymidine kinase i...

Bacterial infections provide diagnostic dilemmas that could be enlightened by modern imaging technologies. We have developed a simple method for imaging bacterial infections in mice that relies on the phosphorylation and trapping of the thymidine kinase (TK) substrate 1-(2'-deoxy-2'-fluoro-beta-D-arabinofuranosyl)-5-[125I] iodouracil ([125I]FIAU) within bacteria. FIAU was found to inhibit the g...

Serum thymidine kinase (sTK) activity was evaluated as a tumor marker for canine malignant lymphoma (ML). The objective was to investigate if sTK, as in humans, could be used as a prognostic marker for survival time in dogs with ML and if sTK could identify early signs of progression of disease in treated dogs. Serum samples from 52 dogs with ML were tested for initial TK activity. Samples from...

A broad variety of herpes simplex virus type 1 clones was selected under a single round of high-dose selection with brivudin. Mutations in the thymidine kinase (TK) genes consisted of 42% frameshift mutations within homopolymer repeats of G's and C's and single nucleotide substitutions (58%) that produced stop codons (Q261 and R281) or a new codon at the site of the substitution (A168T, R51W, G...

We have sequenced a 5.4 kb region of the genome from the avian herpesvirus infectious laryngotracheitis virus (ILTV) and identified genes homologous to the thymidine kinase (TK) gene, the capsid p40 gene of herpes simplex virus type 1 (HSV-1), a gene encoding a protein antigenic in Epstein-Barr virus infections plus one other highly conserved gene encoding a protein implicated in cell fusion in...

The herpes simplex virus thymidine kinase (TK) gene is transcriptionally activated in trans ("transactivated") by virus-encoded proteins during the infectious cycle. We show that TK plasmids introduced into a HeLa cell transient transcription assay system are also transactivated after infection with a TK- virus. Several aspects of this response are similar to regulation during the normal infect...

An emerging strategy for cancer gene therapy involves the transfer of the herpes simplex virus thymidine kinase (HSV-tk) gene into tumor cells, rendering them susceptible to the cytotoxic effects of ganciclovir. The observation that HSV-tk-expressing cells can also induce cell death in neighboring cells, which do not express HSV-tk, has been called the bystander effect. Gap junction-mediated tr...

The thymidine kinase promoter-Renilla luciferase reporter plasmid (pRL-TK) is commonly used as a control for transfection efficiency in the Dual-Luciferase Reporter Assay System. While investigating hormone response elements in the promoters of the androgen-dependent, epididymis-specific EP2 gene, we found that hormone treatment affected the luciferase activity of pRL-TK-transfected cells. In A...