Leo J. Ostruszka

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PURPOSE A recent report of the combination of gemcitabine and docetaxel described favorable results in patients with uterine leiomyosarcoma. The objective of this report is to describe experience with this combination in a variety of histologic subtypes of sarcoma. Additionally, cell-culture studies were performed to assess the effect of the sequence of(More)
Gemcitabine (2',2'-difluoro-2'-deoxycytidine; dFdCyd) has been shown to be a potent radiosensitizer in tumor cells both in vitro and in vivo. We evaluated the ability of dFdCyd to enhance the radiosensitivity of two human glioblastoma cell lines. The results demonstrated that U251 cells were more sensitive to the cytotoxicity of dFdCyd, and that dFdCyd was(More)
We have previously demonstrated (L. Z. Rubsam et al., Cancer Res., 59: 669-675, 1999) that low ganciclovir (GCV) triphosphate (TP) levels similar to cellular deoxynucleotide concentrations can induce multilog killing in cells stably expressing herpes simplex virus thymidine kinase (HSV-TK). In this study, we evaluated whether reducing the endogenous(More)
Because treatment regimens for breast cancer commonly include gemcitabine, we evaluated two promising combinations in preclinical studies: gemcitabine (Gemzar; Eli Lilly and Company, Indianapolis, IN) with either ionizing radiation or docetaxel (Taxotere; Aventis Pharmaceuticals, Inc, Parsippany, NJ). In breast cancer cell lines that expressed either(More)
The herpes simplex virus thymidine kinase (HSV-TK) is the most widely used suicide gene in cancer gene therapy due to its superior anticancer activity with ganciclovir (GCV) compared with other HSV-TK substrates, such as 1-β-D-arabinofuranosyl thymine (araT). We have evaluated the role of DNA damage as a mechanism for the superiority of GCV. Using γ-H2AX(More)
The flow cytometry data file standard provides the specifications needed to completely describe flow cytometry data sets within the confines of the file containing the experimental data. In 1984, the first Flow Cytometry Standard format for data files was adopted as FCS 1.0. This standard was modified in 1990 as FCS 2.0 and again in 1997 as FCS 3.0. We(More)
Cytotoxicity from the anticancer drug 2′,2′-difluoro-2′-deoxycytidine (dFdCyd) has been correlated with its incorporation into DNA. However, cytotoxicity may also result from inhibition of DNA synthesis, due to either (1) dFdCyd diphosphate-mediated inhibition of ribonucleotide reductase, or (2) direct inhibition of DNA polymerases by the 5′-triphosphate of(More)
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