Abstract:
The application discloses therapeutic vaccines based upon the “pING” DNA plasmid vector expressing the gene encoding the rat Her2 protein. Vaccines according to the instant disclosure are used as an adjunct treatment for surgery, radiation and/or chemotherapy for dogs and cats with cancers that over express the Her2 antigen, and prolong the post-surgical disease free interval and/or survival time. Also included are therapeutically effective methods of immunization using said vaccines.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims benefit of U.S. provisional application Ser. No. 61/394,505, filed Oct. 19, 2010. 
    
    
     BACKGROUND OF THE INVENTION 
     This application relates to compositions for treatment of differentiation antigen-dependent cancers and to methods of using such compositions. The invention utilizes compositions containing xenogeneic differentiation antigens, which are associated with cancers to provide effective therapy. 
     Differentiation antigens are tissue-specific antigens that are shared by autologous and some allogeneic tumors of similar derivation, and on normal tissue counterparts at the same stage of differentiation. Differentiation antigens have been shown to be expressed by a variety of tumor types, including melanoma, leukemia, lymphomas, colorectal carcinoma, breast carcinoma, prostate carcinoma, ovarian carcinoma, pancreas carcinomas, and lung cancers. For example, differentiation antigens expressed by melanoma cells include Melan-A/MART-1, Pmel17, tyrosinase, and gp75. Differentiation antigen expressed by lymphomas and leukemia include CD 19 and CD20/CD20 B lymphocyte differentiation markers). An example of a differentiation antigen expressed by colorectal carcinoma, breast carcinoma, pancreas carcinoma, prostate carcinoma, ovarian carcinoma, and lung carcinoma is the mucin polypeptide muc-1. A differentiation antigen expressed by, for example, breast carcinoma is Her2 (synonyms: Her2/neu, ECBB2, ErbB2, c-erb-2), which is a gene coding for a tyrosine kinase receptor that is a member of the family of epidermal growth factor receptors (De Maria et al., 2005). Over expression of Her2 has been demonstrated in mammary gland tumors of both the cat (Winston et al., 2005) and the dog (Rungsipipat et al., 2008). Winston et al. (2005) used existing assay methods (HERCEPTEST™, Dako USA, Carpinteria, Calif.; NCL-CB11, Novocastra, Newcastle, UK) to successfully grade levels of Her2 expression on feline mammary tumors as 0=minimal/absent, 1=weak, 2=moderate, or 3=intense. The HERCEPTEST™ and NCL-CB11 assays identified 27 and 23 cats respectively, out of 30 examined, as having grade 2 or 3 Her2 expression in mammary tumor samples. 
     In addition to successfully grading levels of Her2 over expression in feline mammary tumors, Winston et al. (2005) used the HERCEPTEST™ to detect low levels of Her2 expression in normal feline epithelial tissues and cell types including: hair follicle, mammary gland, gastric pit, salivary gland duct, renal cortical and medullary tubules, colonic and small intestinal crypt, brain, pancreatic duct and islets, splenic macrophages, adrenal cortex, hepatocytes, and testicular Leydig&#39;s cells. Expression of Her2 has been documented on a range of human epithelial cell types including gastro-intestinal, respiratory, reproductive, urinary, skin, mammary and placenta (Press et al., 1990). These findings indicate that the expression of Her2 is common in a range of tissue types of humans and cats. The finding of Her2 over expression in dog mammary tumors suggests this species would share expression characteristics identified in humans and cats. Existing assays and reagents can serve as tools to screen expression levels of Her2 in companion animal cancers in order to justify treatment with the Her2 cancer vaccine. 
     Unfortunately, in most cases, the immune system of the individual is tolerant of such differentiation antigens, and fails to mount an effective immune response. Several technologies have been considered to address this challenge: (cytokines as genetic adjuvants (Chang et al., 2004), xenogeneic vaccination (Pupa et al., 2005), electrotransfer (Quaglino et al., 2004), combination with chemotherapy (Bernhardt et al., 2002). Although results were encouraging, greater efficacy was required for these approaches to be considered a key component of a first-line therapeutic strategy. Further, recent findings indicate both antibody and cell-mediated immunity are required for tumor eradication post immunization, perhaps explaining, in part, the lack of success in the field (Orlandi et al., 2007). Therefore, for the treatment of cancers where the tumor expresses differentiation antigens therefore, it would be desirable to have a method for stimulating a therapeutically effective immune response against the differentiation antigen in vivo. It an object of the present invention to provide such a method. 
     REFERENCES 
     
         
         Orlandi et al. Antibody and CD8 +  T cell Responses against HER2/neu Required for Tumor Eradication after DNA Immunization with a Flt-3 Ligand FusionVaccine. Clin Cancer Res 2007; 13(20) Oct. 15, 2007. 
         Amici A. et al. Venanzi F M, Concetti A. Genetic immunization against neu/erbB2 transgenic breast cancer. Cancer Immunol Immunother 1998; 47:183-90. 
         Bergman P J et al. Long-Term Survival of Dogs with Advanced Malignant Melanoma after DNA Vaccination with Xenogeneic Human Tyrosinase: A Phase I Trial. CCR, Vol. 9, 1284-1290, April 2003. 
         Bargmann et al. The neu oncogene encodes an epidermal growth factor receptor-related protein. Nature. Jan. 16-22; 319(6050):226-30. 
         Norell H et al. Vaccination with a plasmid DNA encoding HER2/neu together with low doses of GM-CSF and IL-2 in patients with metastatic breast carcinoma: a pilot clinical trial. JTM 7 Jun. 2010, 8:53. 
         Jacob, J B et al. Combining Human and Rat Sequences in Her2 DNA Vaccines Blunts Immune Tolerance and Drives Antitumor Immunity; Cancer Res Jan. 1, 2010 70; 119. 
         De Maria R et al. Spontaneous Feline Mammary Carcinoma is a Model of Her2 Overexpressing Poor Prognosis Human Breast Cancer; Cancer Res 2005: 65 (3); 907-912. 
         Philibert J C et al. Influence of Host Factors on Survival in Dogs with Malignant Mammary Gland Tumors; J Vet Intern Med 2003; 17:102-106. 
         Press M F et al. Expression of the Her2/neu proto-oncogene in normal human adult and fetal tissues; Oncogene, 5: 953-62. 
         Rungsipipat A et al.; C-erbB-2 oncogene and P21WAF/CIPI tumor suppressor gene expression as prognostic factors in canine mammary adenocarcinomas; Comp Clin Pathol 2008, 17:35-41. 
         Winston J et al. Immunohistochemical detection of Her=2/neu expression in spontaneous feline mammary tumours; Veterinary and Comparative Oncology 3, 1, 8-15, 2005. 
         Chang S Y et al. Enhanced efficacy of DNA vaccination against Her2/neu tumor antigen by genetic adjuvants; IJC vol 111 pages 86-95, 10 Aug. 2004 
         Pupa et al. HER2: A biomarker at the crossroads of breast cancer immunotherapy and molecular medicine. JCP Vol 205 pages 10-18, 10 May 2005. 
         Quaglino E et al. Concordant morphologic and gene expression data show that a vaccine halts HER2/neu preneoplastic lesions. JCI Vol 113 No 5 Mar. 2004 
         Bernhard H et al. Vaccination against the HER2/neu oncogenic protein. Endocrine-Related Cancer 9 (1) 33-44, 2002. 
         Berta, G N et al. Anti-HER2 DNA vaccine protects Syrian hamsters against squamous cell carcinomas. Br J Cancer, vol 93(11), 28 Nov. 2005. 
         Disis et al. Peptide-based, but not whole protein, vaccines elicit immunity to HER2/neu, an oncogenic self-protein. The Journal of Immunology 156: 3151-3158, May 1, 1996. 
         Eck et al. (Gene Based Therapy in The Pharmacological Basis of Therapeutics, Goodman and Gilman, Eds, 1996, pp. 77-101). 
         Zhai et al. Antigen-Specific Tumor Vaccines. The Journal of Immunology 156: 700-710, January 1996. 
         Verma and Somia. Gene and therapy-promises, problems and prospects. Nature 389: 239-242, September 1997. 
         Miller and Vile. Targeted vectors for gene therapy. FASEB J. 9: 190-199, 1995. 
         Deonarain, Mahendra. Ligand-targeted receptor-mediated vectors for gene delivery. Exp. Opin. Ther. Patents 8(1): 53-69, 1998. 
         Crystal. Transfer of Genes to Humans: Early Lessons and Obstacles to Success. Science 270: 404-410, Oct. 20, 1995. 
         B. Bouchard et al., “Induction of Pigmentation in Mouse Fibroblasts by Expression of Human Tyrosinase cDNA”, J. Exp. Med., 1989, vol. 169, pp. 2029-2042. 
         B. Bouchard et al., “Production and Characterization of Antibodies against Human Tyrosinase”, The Journal of Investigative Dermatology, 1994, vol. 102, No. 3, pp. 291-295. 
         J. Rowell et al., “Lysosome-Associated Membrane Protein-1-Mediated Targeting of the HIV-1 Envelope Protein to an Endosomal/Lysosomal Compartment Enhances Its Presentation to MHC Class II-Restricted T Cells”, The American Association of Immunologists, 1995, pp. 1818-1828. 
         S. Krishnan et al., “Paving the way towards DNA vaccines”, Nature Medicine, 1995, vol. 1, No. 6, pp. 521-522. 
         S. Barclay et al., “Rapid isolation of monoclonal antibodies specific for cell surface differentiation antigens”, Proc. Natl. Acad. Sci. USA, 1986 vol. 83, pp. 4336-4340. 
         S. Vijayasaradhi et al., “Intracellular Sorting and Targeting of Melanosomal Membrane Proteins: Identification of Signals for Sorting of the Human Brown Locus Protein, GP75”, The Journal of Cell Biology, 1995, vol. 130, No. 4, pp. 807-820. 
         D. Pardoll et al., “Exposing the Immunology of Naked DNA Vaccines”, Immunity, Cell Press, 1995, vol. 3, pp. 165-169. 
         S. Vijayasaradhi et al., “The Melanoma Antigen gp75 is the Human Homologue of the Mouse b (Brown) Locus Gene Product”, J. Exp. Med., 1990, vol. 171, pp. 1375-1380. 
         G. Adema et al., “Molecular Characterization of the Melanocyte Lineage-specific Antigen gp100”, The Journal of Biology Chemistry, The American Society for Biochemistry and Molecular Biology, 1994, vol. 269, No. 31, pp. 20126-20133. 
         A. Houghton et al., “Recognition of Autoantigens by Patients with Melanoma”, Annals New York Academy of Sciences, 1993, pp. 59-69. 
         C. Naftzger et al., “Immune response to a differentiation antigen induced by altered antigen: A study of tumor rejection and autoimmunity”, Proc. Natl. Acad. Sci. USA, 1996, vol. 93, pp. 14809-14814. 
         F. Ausubel et al., “Expression of Proteins is Insect Cells using Baculoviral Vectors”, Current Protocols in Molecular Biology, Greene Publishing and Wiley-Interscience, 1990, vol. 8, 16.8.1-16.11-7. 
         J. Ulmer et al., “Heterologous Protection Against Influenza by Injection of DNA Encoding a Viral Protein”, Science, 1993, vol. 259, pp. 1745-1749. 
         C. Tiffs et al., “The Folding and Cell Surface Expression of CD4 Requires Glycosylation”, The Journal of Biological Chemistry, 1992, vol. 267, No. 5, pp. 3268-3273. 
         S. Park, “JL1, A Novel Differentiation Antigen of Human Cortical Thymocyte”, J. Exp. Med., The Rockefeller University Press, 1993, vol. 178, pp. 1447-1451. 
         C. Cabanas et al., “Characterization of a CD11c-Reactive Monoclonal Antibody (HCI/I) Obtained by Immunizing with Phorbol Ester Differentiated U937 Cells”, Hybridoma, 1988, vol. 7, No. 2, pp. 167-177. 
         N. Nanda et al., “Induction of Anti-Self-Immunity to Cure Cancer”, Cell, 1995, vol. 82, pp. 13-17. cited by other. 
       
    
     All of the above-mentioned applications, patents and references are herein incorporated in their entirety by reference. 
     SUMMARY OF THE INVENTION 
     It has now been found that the tolerance of the immune system for self-derived target differentiation antigens can be overcome and an immune response stimulated by administration of a xenogeneic differentiation antigen (wild-type or mutant) of the same type from a species different from the subject being treated (U.S. Pat. No. 6,328,969 &amp; U.S. Pat. No. 7,556,805, to Sloan-Kettering, both incorporated by reference herein). For example, a rat differentiation antigen can be used to stimulate an immune response to the corresponding differentiation antigen in a canine subject. Administration of altered antigens in accordance with the invention results in an effective immunity against the original antigen expressed by the cancer in the treated subject. Thus, in accordance with a first aspect of the invention, there is provided a method for treating in a mammalian subject, comprising the step of administering to the subject an immunologically-effective amount of a xenogeneic mammary gland tumor-associated differentiation antigen. 
     Therapeutic differentiation antigens based on mammary gland carcinoma/tumor-associated differentiation antigens are used in accordance with the invention to treat, for example, mammary gland carcinoma post-surgical removal of tumors in subjects suffering from said cancers. In one embodiment of the invention, a plasmid comprising a sequence encoding a xenogeneic tyrosine kinase receptor, for example rat tyrosine kinase receptor, under the control of a suitable promoter, is administered to a subject. For example, dogs have been treated using plasmids comprising a DNA sequence encoding rat tyrosine kinase receptor with pronounced clinical benefit. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1A  shows overall survival time post-immunization and surgical resection of MGT; 
         FIG. 1B  shows disease-free survival time post-immunization and surgical resection of MGT; 
         FIG. 1C  shows metastasis-free survival time post-immunization and surgical resection of MGT; 
         FIG. 2  shows a map of the pcDNA3.1 (+/−) plasmid; 
         FIG. 3  shows the nucleotide sequence for the pINGhumanTyrosinase plasmid, where the coding sequence for the human tyrosinase has been removed. This is the location into which the rat Her2/neu (nucleotides 17-3799 of SEQ ID NO:1) was inserted to produce the rHer2/neu-pING of the instant invention; 
         FIG. 4  shows a map of the pINGhumanTyrosinase plasmid. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The present invention provides a method for treating mammary gland tumors in a subject by stimulating an immune response to a mammary gland-associated differentiation antigen. The subject is preferably canine or feline, although the invention can be applied to other animal species, preferably mammalian or avian species, as well. 
     As used in the specification and claims of this application, the term “immune response” encompasses both cellular and humoral immune responses. Preferably, the immune response is sufficient to provide immunoprotection against growth of tumors expressing the target differentiation antigen. The term “stimulate” refers to the initial stimulation of a new immune response or to the enhancement of a pre-existing immune response. 
     In accordance with the invention, a subject is treated by administering a xenogeneic differentiation antigen of the same type as a target differentiation antigen expressed by mammary gland tumor cells of the subject in an amount effective to stimulate an immune response. Thus, for example, if the target differentiation antigen is the Her2/neu antigen found in mammary cells, the therapeutic antigen is a xenogeneic Her2/neu antigen. 
     In one embodiment, the inventive method may include the following steps: (1) immunization to an animal in need of a xenogeneic antigen, for example, the rat Her2/neu as set forth in SEQ ID NO:2 and encoded by nucleotides 106-3885 of the sequence as set forth in SEQ ID NO:1, (2) needle-free priming of immune responses, (3) electrotransfer-based booster, and (4) vaccination after tumor debulking by surgical primary therapy. 
     In another embodiment, the inventive method is carried out on subjects, including companion animals, without metastasis (i.e. in relatively early stages of mammary carcinoma disease progression). 
     In some embodiments, the boost comprises administering plasmids encoding xenogeneic antigens, for example those encoding rat Her2 protein (SEQ ID NO:2). 
     In some embodiments, the xenogeneic antigen is encoded by a nucleotide having favorable nucleotide substitutions with respect to the sequence as set forth in SEQ ID NO:1. Favorable substitutions include any changes that result in improved immune response against the Her2/neu expressed by the cells of the mammary tumor/carcinoma. Substitutions can include existing sequences, such as murine Her2 (SEQ ID NO:3), human Her2 (SEQ ID NO:4), or any other xenogeneic Her2 sequence, or fragment thereof, capable of eliciting a therapeutically effective immune response in a target animal against a Her2-associated mammary carcinoma. 
     In some embodiments, the boost comprises administering a xenogeneic differentiation antigen. 
     In other embodiments, the boost comprises administering a syngeneic differentiation antigen. 
     Xenogeneic differentiation antigen may be administered as a purified differentiation antigen derived from the source organism. Proteins can be purified for this purpose from cell lysates using column chromatography procedures. Proteins for this purpose may also be purified from recombinant sources, such as bacterial or yeast clones or mammalian or insect cell lines expressing the desired product. 
     Administration of the xenogeneic differentiation antigen can be accomplished by several routes. First, the xenogeneic differentiation antigen may be administered as part of a vaccine composition which may include one or more adjuvants such as alum, QS21, TITERMAX or its derivatives, incomplete or complete Freund&#39;s and related adjuvants, and cytokines such as granulocyte-macrophage colony stimulating factor, flt-3 ligand, interleukin-2, interleukin-4 and interleukin-12 for increasing the intensity of the immune response. The vaccine composition may be in the form of a xenogeneic differentiation antigen in a solution or a suspension, or the therapeutic differentiation antigen may be introduced in a lipid carrier such as a liposome. Such compositions will generally be administered by subcutaneous, intradermal or intramuscular route. Vaccine compositions containing expressed xenogeneic differentiation antigen are administered in amounts which are effective to stimulate an immune response to the target differentiation antigen in the subject. The preferred amount to be administered will depend on the species of the subject and on the specific antigen, but can be determined through routine preliminary tests in which increasing doses are given and the extent of antibody formation or T cell response is measured by ELISA or similar tests. T cell responses may also be measured by cellular immune assays, such as cytotoxicity, cytokine release assays and proliferation assays. 
     The xenogeneic differentiation antigen may also be introduced in accordance with the invention using a DNA immunization technique in which DNA encoding the antigen is introduced into the subject such that the xenogeneic differentiation antigen is expressed by the subject. cDNA encoding the differentiation antigen is combined with a promoter which is effective for expression of the nucleic acid polymer in mammalian cells. This can be accomplished by digesting the nucleic acid polymer with a restriction endonuclease and cloning into a plasmid containing a promoter such as the SV40 promoter, the cytomegalovirus (CMV) promoter or the Rous sarcoma virus (RSV) promoter. The resulting construct is then used as a vaccine for genetic immunization. The nucleic acid polymer could also be cloned into plasmid and viral vectors that are known to transduce mammalian cells. These vectors include retroviral vectors, adenovirus vectors, vaccinia virus vectors, pox virus vectors and adenovirus-associated vectors. 
     The nucleic acid constructs containing the promoter and the antigen-coding region can be administered directly or they can be packaged in liposomes or coated onto colloidal gold particles prior to administration. Techniques for packaging DNA vaccines into liposomes are known in the art, for example from Murray, ed. “Gene Transfer and Expression Protocols” Humana Pres, Clifton, N.J. (1991). Similarly, techniques for coating naked DNA onto gold particles are taught in Yang, “Gene transfer into mammalian somatic cells in vivo”, Crit. Rev. Biotech. 12: 335-356 (1992), and techniques for expression of proteins using viral vectors are found in Adolph, K. ed. “Viral Genome Methods” CRC Press, Florida (1996). 
     For genetic immunization, the vaccine compositions are preferably administered intradermally, subcutaneously or intramuscularly by injection or by gas driven particle bombardment, and are delivered in an amount effective to stimulate an immune response in the host organism. The compositions may also be administered ex vivo to blood or bone marrow-derived cells (which include APCs) using liposomal transfection, particle bombardment or viral infection (including co-cultivation techniques). The treated cells are then reintroduced back into the subject to be immunized. While it will be understood that the amount of material needed will depend on the immunogenicity of each individual construct and cannot be predicted a priori, the process of determining the appropriate dosage for any given construct is straightforward. Specifically, a series of dosages of increasing size, starting at about 0.1 μg is administered and the resulting immune response is observed, for example by measuring antibody titer using an ELISA assay, detecting CTL response using a chromium release assay or detecting TH (helper T cell) response using a cytokine release assay. 
     Once tolerance is broken through the administration of the xenogeneic differentiation antigen, subsequent treatments with syngeneic differentiation may be employed to maintain and in some cases enhance the immune response. (See, Weber, et al., “Tumor immunity and autoimmunity induced by immunization with homologous DNA.” J Clin Invest 102 (6):1258 (1998).) Thus, in one embodiment of the invention, the subject is first treated by administration of a xenogeneic differentiation antigen (for example for three treatment cycles), and subsequently by administration of a syngeneic differentiation antigen (for example for an additional three treatment cycles). As an alternative to treatment cycles using different therapeutic agents, one can use a single therapeutic agent containing both xenogeneic and syngeneic differentiation antigens. Thus, for example, a mixture of the rHer2-pING and hHer2-pING vectors, or a single vector encoding both rat and human Her2/neu under the control of a promoter such that they are expressed in a canine subject can be employed for the treatment of mammary gland tumor in canines. Vectors are available commercially, for example from Stratagene and other companies, which can express two independent genes. Commonly, these vectors use an internal ribosomal entry site, or IRES, between the two genes. This approach has the advantage of requiring approval for only a single therapeutic agent. 
     All documents cited herein are herein incorporated by reference in their entirety. 
     The invention will now be further described with reference to the following, non-limiting examples. 
     EXAMPLE 1 
     Her2/Neu Expression Plasmid Construction 
     The extracellular domain of rat HER2/neu (nucleotides 17-3799 of SEQ ID NO:1) was amplified by PCR from the pCMVneuNT (Amici et al., 1998) plasmid using the primers forward: 5′-CGAAGCTTACCATGGAGCTGGCGGCCTGG-3′ (SEQ ID NO:6) and reverse: 5′-CGGAATTCTTATGTCACCGGGCTGGC-3′ (SEQ ID NO:7). The HindIII-EcoRI fragment was cloned into pcDNA3.1(+) (Invitrogen, Carlsbad, Calif.; and  FIG. 2 ). The original sequence of the rat neu cDNA was described previously (Bargmann et al., 1986), and is herein set forth in SEQ ID NO:1, with the coding sequence from nucleotides 17 to 3799. The rat HER2/neu coding sequence was then subcloned into the pING vector (Bergman et al., Clin Cancer Res, 9: 1284-1290, 2003, backbone depicted in  FIG. 3 ; map depicted in  FIG. 3A ; and sequence as set forth in SEQ ID NO:5), to yield rat HER2/neu-pING. 
     EXAMPLE 2 
     Immunization of Mammary Gland Tumor (MGT)-Positive Canines with pING-rHer2 
     In this trial, 10 dogs with MGT were enrolled and immunized with 100 μg of pING-rHer2 DNA per dose. The signalment for these dogs is set forth in Table 1 and the tumor staging is set forth in Table 2. 
     
       
         
               
             
               
               
               
               
             
               
               
               
               
               
             
           
               
                 TABLE 1 
               
             
             
               
                   
               
               
                 Trial animal characteristics 
               
             
          
           
               
                   
                 Age 
                   
                 Weight 
               
               
                   
                 (yrs) 
                 Breed 
                 (kg) 
               
               
                   
                   
               
             
          
           
               
                   
                 MGT 01 
                 9 
                 Yorkshire Terrier 
                 1.75 
               
               
                   
                 MGT 02 
                 13 
                 Mixed 
                 9.8 
               
               
                   
                 MGT 03 
                 12 
                 Yorkshire Terrier 
                 5 
               
               
                   
                 MGT 04 
                 7 
                 Lhasa Apso 
                 11 
               
               
                   
                 MGT 05 
                 10 
                 Maltese 
                 3.35 
               
               
                   
                 MGT 06 
                 12 
                 Cavalier King Charles Spaniel 
                 9 
               
               
                   
                 MGT 07 
                 8 
                 Pomeranian 
                 2.8 
               
               
                   
                 MGT08 
                 12 
                 Maltese 
                 3.9 
               
               
                   
                 MGT09 
                 13 
                 Pomeranian 
                 2.7 
               
               
                   
                 MGT10 
                 12 
                 Yorkshire Terrier 
                 3 
               
               
                   
                 Median 
                 12 
                 — 
                 3.6 
               
               
                   
                   
               
             
          
         
       
     
                                                         TABLE 2                   Tumor staging                Tumor size (cm)   MGT Type   Stage                        MGT 01   2 × 2 × 4   Tubulopapillary carcinoma   T 3 N 0 M 0             0.2 × 0.2 × 0.2           0.2 × 0.3 × 0.2           0.1 × 0.1 × 0.1           0.5 × 0.5 × 0.5           0.2 × 0.2 × 0.2           0.5 × 0.5 × 0.5       MGT 02   12 × 10 × 8   Lipid rich carcinoma   T 3 N 0 M 0             5 × 3 × 1.5           1 × 1 × 1           1 × 1 × 0.5           0.5 × 0.1 × 0.1       MGT 03   5.6 × 4.8 × 4.6   Tubulopapillary carcinoma with   T 3 N 0 M 0             1.8 × 1.5 × 1.2   fibroadenoma       MGT 04   4.2 × 5.6 × 2.5   Tubulopapillary carcinoma   T 3 N 0 M 0         MGT 05   1.2 × 1 × 0.5   Simple adenoma   T 1 N 0 M 0             1 × 1.4 × 0.5           1 × 1 × 0.4           0.5 × 0.5 × 0.5       MGT 06   10 × 4 × 3   Lipid rich carcinoma with   T 3 N 0 M 0                 fibroadenoma       MGT 07   1 × 1 × 1   Complex type   T 1 N 0 M 0             0.5 × 0.5 × 0.5       MGT08   1 × 1 × 1   Complex type   T 1 N 0 M 0             0.5 × 0.5 × 0.5       MGT09   2.5 × 2 × 1   Complex type   T 1 N 0 M 0             1.5 × 2 × 1       MGT10   1 × 1 × 1   Tubulopapillary carcinoma   T 1 N 0 M 0             0.5 × 0.5 × 0.5           0.1 × 0.1 × 0.1                    
As indicated, this group included five stage I and five stage III dogs, which all received three doses of vaccine at two week intervals. The first and second doses were administered with the VITAJET™ transdermal device and the third dose by intramuscular injection concurrent with electroporation. Vaccination was initiated following surgical removal of the MGT with concurrent ovariohysterectomy (OHE). All dogs were negative for regional lymph node and pulmonary metastasis. Disease free survival and overall survival times were calculated using day of surgery as day 0 with results presented in Table 3.
 
     
       
         
               
             
               
               
               
             
               
               
               
               
               
             
               
               
               
               
               
               
             
               
               
               
               
               
             
               
               
               
               
               
               
             
               
               
               
               
               
             
           
               
                 TABLE 3 
               
             
             
               
                   
               
               
                 Disease-free and overall survival time 
               
             
          
           
               
                   
                 Overall 
                   
               
             
          
           
               
                   
                 WHO 
                 Disease-free survival 
                 survival time 
                   
               
             
          
           
               
                 Dog 
                 Stage 
                 recurrence 
                 metastasis 
                 (days) 
                 Outcome 
               
               
                   
               
               
                 MGT 05 
                 I 
                 703 
                 703 
                 703 
                 alive 
               
               
                 MGT 07 
                 I 
                 669 
                 669 
                 669 
                 alive 
               
               
                 MGT 08 
                 I 
                 548 
                 548 
                 548 
                 alive 
               
               
                 MGT 09 
                 I 
                 536 
                 536 
                 536 
                 alive 
               
               
                 MGT 10 
                 I 
                 482 
                 482 
                 482 
                 dead 
               
             
          
           
               
                 Stage I Dogs 
                 548 
                 548 
                 548 
                 — 
               
             
          
           
               
                 MGT 01 
                 III 
                 779 
                 779 
                 779 
                 alive 
               
               
                 MGT 02 
                 III 
                 212 
                 182 
                 212 
                 dead 
               
               
                 MGT 03 
                 III 
                 762 
                 762 
                 762 
                 alive 
               
               
                 MGT 04 
                 III 
                 575 
                 381 
                 720 
                 alive w/met 
               
               
                 MGT 06 
                 III 
                 686 
                 686 
                 686 
                 alive 
               
             
          
           
               
                 Stage III Dogs 
                 686 
                 686 
                 720 
                 — 
               
               
                 All Dogs Median 
                 622 
                 609 
                 678 
               
               
                   
               
             
          
         
       
     
     A group of 19 dogs was identified as historical control cases. All control dogs underwent surgical removal of MGT with concurrent OHE and were negative for regional lymph node and pulmonary metastasis. This group included 7 stage I, 3 stage II, and 9 stage III dogs. Disease free and overall survival times were calculated for these dogs using day of surgery as day 0. The signalment for these dogs is set forth in Table 4 and tumor staging for each dog is set forth in Table 5. Disease free and overall survival times were calculated for the control group and are presented in  FIGS. 1A-1C . 
     
       
         
               
             
               
               
               
               
               
             
               
               
               
               
               
             
           
               
                 TABLE 4 
               
             
             
               
                   
               
               
                 Control dog signalment 
               
             
          
           
               
                   
                   
                 Age 
                   
                 Weight 
               
               
                   
                 Case Number 
                 (yrs) 
                 Breed 
                 (kg) 
               
               
                   
                   
               
             
          
           
               
                 1 
                 9403460 
                 7 
                 Mix 
                 1.75 
               
               
                 2 
                 9404023 
                 14 
                 Poodle 
                 2.5 
               
               
                 3 
                 9405132 
                 14 
                 Yorkshire 
                 2.3 
               
               
                 4 
                 9409179 
                 12 
                 Finnish Spitz 
                 6.8 
               
               
                 5 
                 9409043 
                 14 
                 Poodle 
                 3.2 
               
               
                 6 
                 9500057 
                 9 
                 Lhasa Apso 
                 6.5 
               
               
                 7 
                 9500890 
                 14 
                 Maltese 
                 6 
               
               
                 8 
                 9500959 
                 15 
                 Cocker 
                 14 
               
               
                 9 
                 923543 
                 11 
                 Siberian Huskies 
                 16 
               
               
                 10 
                 9405082 
                 13 
                 Poodle 
                 3.9 
               
               
                 11 
                 9505202 
                 9 
                 Mix 
                 12 
               
               
                 12 
                 9600998 
                 10 
                 Maltese 
                 4.6 
               
               
                 13 
                 9700451 
                 13 
                 Maltese 
                 2.7 
               
               
                 14 
                 892285 
                 12 
                 Yorkshire 
                 1.6 
               
               
                 15 
                 9502927 
                 14 
                 Maltese 
                 3.2 
               
               
                 16 
                 9405356 
                 10 
                 Cocker 
                 12 
               
               
                 17 
                 9409104 
                 11 
                 Maltese 
                 3.8 
               
               
                 18 
                 9503957 
                 6 
                 Miniature Schnauzer 
                 4 
               
               
                 19 
                 9404023 
                 14 
                 Poodle 
                 3 
               
               
                   
                 Median 
                 12 
                   
                 3.9 
               
               
                   
               
             
          
         
       
     
     
       
         
               
             
               
               
               
               
               
             
               
               
               
               
               
             
           
               
                 TABLE 5 
               
             
             
               
                   
               
               
                 Tumor staging for control dogs 
               
             
          
           
               
                   
                 Clinical NO. 
                 Tumor size 
                 MGT Type 
                 Stage 
               
               
                   
                   
               
             
          
           
               
                 1 
                 9403460 
                 6 × 6 × 7 
                 Complex carcinoma 
                 T 3 N 0 M 0   
               
               
                 2 
                 9404023 
                 3 × 3 × 3 
                 Squamous cell carcinoma 
                 T 2 N 0 M 0   
               
               
                 3 
                 9405132 
                 7 × 4 × 7 
                 Simple or 
                 T 3 N 0 M 0   
               
               
                   
                   
                 2 × 2 × 2 
                 complex carcinoma 
               
               
                   
                   
                 0.3 × 0.2 × 0.2 
               
               
                   
                   
                 0.5 × 0.5 × 0.5 
               
               
                 4 
                 9409179 
                 13 × 12 × 12 
                 Simple carcinoma with 
                 T 3 N 0 M 0   
               
               
                   
                   
                 6 × 7 × 7 
                 squamous cell carcinoma 
               
               
                   
                   
                 1 × 1 × 1 
               
               
                 5 
                 9409043 
                 3.5 × 2. × 1 
                 Tubulopapillary 
                 T 2 N 0 M 0   
               
               
                   
                   
                 3 × 1.5 × 1 
                 carcinoma 
               
               
                 6 
                 9500057 
                 3 × 2 × 2 
                 Tubulopapillary 
                 T 2 N 0 M 0   
               
               
                   
                   
                 2 × 1 × 1 
                 carcinoma 
               
               
                 7 
                 9500890 
                 8 × 3 × 1 
                 Simple carcinoma 
                 T 3 N 0 M 0   
               
               
                 8 
                 9500959 
                 8 × 3 × 2 
                 Adenocarcinoma 
                 T 3 N 0 M 0   
               
               
                   
                   
                 2 × 1 × 0.5 
               
               
                 9 
                 923543 
                 5 × 5 × 4 
                 Simple carcinoma 
                 T 3 N 0 M 0   
               
               
                   
                   
                 0.2 × 0.2 × 0.2 
               
               
                 10 
                 9405082 
                 5 × 4 × 3.5 
                 Simple carcinoma 
                 T 3 N 0 M 0   
               
               
                   
                   
                 3 × 3.5 × 3 
               
               
                 11 
                 9505202 
                 0.3 × 0.3 × 0.3 
                 Tubulopapillary 
                 T 1 N 0 M 0   
               
               
                   
                   
                 1 × 1 × 0.5 
                 carcinoma 
               
               
                   
                   
                 0.4 × 0.4 × 0.4 
               
               
                 12 
                 9600998 
                 0.5 × 0.5 × 0.4 
                 Carcinoma 
                 T 1 N 0 M 0   
               
               
                   
                   
                 1 × 0.5 × 0.5 
               
               
                 13 
                 9700451 
                 1 × 1 × 1 
                 Tubulopapillary 
                 T 1 N 0 M 0   
               
               
                   
                   
                 1 × 1 × 1 
                 carcinoma 
               
               
                 14 
                 892285 
                 0.5 × 0.8 × 0.3 
                 Carcinoma in benign 
                 T 1 N 0 M 0   
               
               
                   
                   
                 1 × 0.8 × 0.5 
                 mixed tumor 
               
               
                 15 
                 9502927 
                 5 × 4 × 4 
                 Carcinoma in benign 
                 T 3 N 0 M 0   
               
               
                   
                   
                 0.5 × 0.5 × 0.5 
                 mixed tumor 
               
               
                 16 
                 9405356 
                 10 × 3 × 1.5 
                 Tubulopapillary 
                 T 3 N 0 Mo 
               
               
                   
                   
                   
                 carcinoma 
               
               
                 17 
                 9409104 
                 1 × 1 × 1 
                 Adenocarcinoma 
                 T 1 N 0 M 0   
               
               
                   
                   
                 0.5 × 0.5 × 0.5 
               
               
                   
                   
                 2 × 2 × 2 
               
               
                 18 
                 9503957 
                 2 × 2 × 2 
                 Adenocarcinoma, 
                 T 1 N 0 M 0   
               
               
                   
                   
                 0.3 × 0.3 × 0.3 
                 complex type 
               
               
                 19 
                 9404023 
                 2 × 2 × 1 
                 Adenocarcinoma, 
                 T 1 N 0 M 0   
               
               
                   
               
             
          
         
       
     
     Philibert et al. (2003) reviewed survival statistics for 97 dogs with MGT and reported median survival times for 41 dogs with MGT less than 3 cm in diameter to be 22 months (˜666 days) versus 14 months (˜424 days) for 56 dogs with MGT greater than 3 cm in diameter. In the absence of lymph node involvement or metastasis, tumor size less than 3 cm correlates with stage I disease and greater than 3 cm correlates with stage II or higher disease status. They did not find a difference in survival time for dogs in stages II, III or IV. 
     Overall median survival time for all dogs treated with the pING-rHer2 vaccine is 678 days. This was significantly higher as compared to the historical data from the 19 dogs provided by NTU indicating a median overall survival time of 300 days, and to the data published by Philibert et al. (2003) indicating 424 days overall survival time for dogs with stage II or greater MGT. 
     The pING-rHer2 DNA vaccine will target dogs and cats with tumors shown to over express the Her2 antigen based upon tumor tissue analysis using existing Her2 tissue expression assays. The vaccine will be administered using the Vetjet™ transdermal device to deliver 100 μg of DNA into the medial thigh of dogs or lateral thigh of cats, at two week intervals for four doses. Dogs and cats that survive will receive a booster dose every six months. 
     The invention will now be described by the following non-limiting claims.