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The goal of the experiments was to test if the acetylenes could be used to suppress the in vivo growth of P210Bcr-Abl dependent cell lines. The work completed during the funding showed that the acetylene compound K1P which had been shown to suppress the in vitro growth of CML cells which are resistant to imatinib and to inhibit p210Bcr-Abl dependent in vitro CML cell growth at the nanomolar concentrations when combined with imatinib could also suppress the in vivo growth of a P210Bcr-Abl dependent cell line (Baf-1P210Bcr-Abl). These studies also showed that the medium in which the drugs were dissolved must contain 0.1% ethanol to increase the solubility sufficiently to suppress in vivo P210Bcr-Abl dependent cell growth. Finally the presence of serum in the medium used to expose the drugs to the P210Bcr-Abl dependent cells blocked the suppressive activity of the drugs despite the presence of 0.1% ethanol. These data suggested that chemical functionalities which could improve the bioavailability of the drugs in the presence of serum needed to be added to the ester side chain of the acetylene compounds. This work once completed will enable further in vivo toxicity and efficacy studies to proceed. more...

The objective is to design, build and study vectors which would be able to break tolerance to breast cancer associated TAA and to be used to suppress the recurrence of metastatic breast cancer following surgical resection. The hypothesis is that by fusing the CD40 ligand stripped of its transmembrane domain and intracytoplasmic domains, to a breast cancer TAA such as the extracellular domain of the her-2-neu receptor, or the extracellular tandem repeat peptides of breast cancer associated surface glycoprotein, MUC-1 (both of which have been shown to be capable when loaded on APCs of conferring resistance to engraftment by cancer cells bearing these TAA), one can break tolerance to breast cancer. The subcutaneous injection of this vector creates infected cells as factories to secrete the CD40LTAA into the systemic circulation as well as locally for the activation and antigen loading of APCs, so that they would move to the lymph nodes all over the body to generate the CD8 dependent response against metastatic breast cancer. We also explored boosting of the vector vaccine by TAA/CD40L protein injections. This report summarizes the successful assembly and study of these vectors. These injections break tolerance to tumor associated antigens in mouse models., The original document contains color images. more...

Pre-clinical testing has shown that subcutaneous injection of an Ad-sig-TAA/ecdCD40L adenoviral vaccine strategy overcomes anergy to tumor associated antigens (TAA) in mice which are genetically engineered to be tolerant of these antigens. Two injections of the vector confer up to a year's immunity and induce regressions of TAA positive tumor even in old (18mo. Old) mice which are known to be poorly responsive to vaccination. This is important since diminished response to vaccine has been seen clinically in human subjects in the age range of peak prevalence of prostate cancer. We have chosen to use hMUC-1, an antigen which is a marker of poor prognosis in prostate cancer, for the clinical development of this vaccine. We have completed the development of a phase I clinical protocol of the ad-sig-hMUC-1/ecdCD40L adenoviral vector vaccine for individuals diagnosed with localized prostate cancer who have evidence of recurrence of their prostate cancer (rising PSA) following radiation therapy for clinically localized disease. We are in the midst of completing the pharmacology, toxicology, and biodistribution assays, GMP production of the Ad-sig-hMUC-1/ecdCD40L and the quality control testing of the GMP production, all of which are needed for FDA approval of the phase I trial is arranged., The original document contains color images. more...

The objective is to design, build and study vectors which would be able to break tolerance to breast cancer associated TAA and be used to suppress the recurrence of metastatic breast cancer following surgical resection. The hypothesis is that by fusing the CD40 ligand stripped of its transmembrane domain and intracytoplasmic domains, to a breast cancer TAA such as the extracellular domain of the her-2-neu receptor, or the extracellular tandem repeat peptides of breast cancer associated surface glycoprotein, MUC-1 (both of which have been shown to be capable when loaded on APCs of conferring resistance to engraftment by cancer cells bearing these TAA), one can break tolerance to breast cancer. The subcutaneous injection of this vector creates infected cells as factories to secrete the CD40LTAA into the systemic circulation as well as locally for the activation and antigen loading of APCs, so that they would move to the lymph nodes all over the body to generate a CD8 dependent response against metastatic breast cancer. We also explored boosting of the vector vaccine by TAA/CD40L protein injections. This report summarizes the successful assembly and study of these vectors. These injections break tolerance to tumor associated antigens in mouse models. more...

We have developed a safety modified adenoviral vector in which the tumor specific L-plastin promoter can be used to control the expression of therapeutic genes such as cytosine deaminase (CD). The CD gene product catalyzes the conversion of a non-toxic precursor, 5-Fluorocytosine (5FC) into a drug, 5-Fluorocytosine (5FC), thereby sensitizing the cells in which it is produced to 5FC induced toxicity. We have also generated vectors in which the adenovirus needs to replicate within mammalian cells. The replication of a virus within a mammalian cell takes over all of the metabolic and cell proliferative machinery of%the cells and thereby kills it. Our data shows that the adenoviral vector which carries the L-plastin-ElA transcription unit can replicate within breast cancer cells and other estrogen dependent carcinomas, such as ovarian cancer, while not being able to replicate in normal cells. This L-plastin-ElA vector can suppress the growth of human breast cancer cell lines in immunosuppressed mice. We have recently isolated a vector in which both the CD ElA genes are under the control of the L-plastin promoter, which is currently under study., The original document contains color images. All DTIC reproductions will be in black and white. more...

Once breast cancer recurs after initial surgery or radiation therapy and is found to be incompletely responsive to salvage chemotherapy, there is no established treatment that can prolong survival. To address this problem, the Deisseroth laboratory has developed a series of vectors that are directed at the use of the L-plastin tumor-specific transcriptional promoter to control the expression of a chemotherapy sensitization gene (cytosine deaminase) and a viral replication gene (ElA) so that any toxic effect is tumor specific. These vectors have been shown to suppress the growth of human breast cancer cell lines in a SCID mouse model, and to produce a direct cytolytic effect on breast cancer cell lines which is not seen in explant cultures of normal breast epithelial cells. By combining the ElA and the CD transcription units in a single vector the authors have shown that this vector is superior to vectors with a single ElA or CD transcription unit. The authors will now complete the steps necessary for this vector to be available for therapy and will study the use of this vector in combination with chemotherapy as a means to directly kill breast cancer cells and to control metastatic breast cancer., The original document contains color images. All DTIC reproductions will be in black and white. more...