Abstract: This invention provides a method for preparing a hybridoma cell line which produces a monoclonal antibody which specifically recognizes and binds to a tumor associated antigen which comprises: (a) cotransfecting a CREF-Trans 6 cell line with DNA isolated from a neoplastic, human cell and a plasmid which encodes a selectable or identifiable trait; (b) selecting transfected cells which express the selectable or identifiable trait; (c) recovering the cells so selected in step (b); (d) injecting the cells so recovered in step (c) into a suitable marine host; (e) maintaining the resulting first murine host for a period of time effective to induce the cells injected in step (d) to form a tumor in the murine host; (f) isolating the tumor formed in step (e); (g) obtaining tumor cells from the isolated tumor in step (f); (h) coating the tumor cells obtained in step (9) with an antiserum generated against the CREF Trans-6 cell line (i) injecting the antiserum-coated cells from step (h) into a plurality of suitable seco

Abstract: This invention provides an isolated nucleic acid molecule encoding a Progression Elevated Gene-3 protein. This invention also provides isolated nucleic acid molecule encoding a human Progression Elevated Gene-3 protein. This invention provides a nucleic acid molecule of at least 12 nucleotides capable of specifically recognizing a nucleic acid molecule encoding a Progression Elevated Gene-3 protein. This invention provides a method of detecting expression of the Progression Elevated Gene-3 in a sample. This invention provides an isolated nucleic acid molecule encoding a Progression Elevated Gene-3 protein operatively linked to a regulatory element. This invention provides a host vector system for the production of a polypeptide having the biological activity of a Progression Elevated Gene-3 protein. This invention also provides a purified Progression Elevated Gene-3 protein and a fragment thereof. This invention provides an antibody capable of specifically binding to a Progression Elevated Gene-3 protein.

Abstract: This invention provides a method for producing a temporally spaced subtracted cDNA library comprising: a) isolating temporally spaced RNAs from cells; b) generating cDNA inserts from the RNAs isolated from step (a); c) producing a temporally spaced cDNA library having clones containing the cDNA inserts generated from step (b); d) producing double stranded cDNA inserts from the temporally spaced cDNA library; e) denaturing the double stranded cDNA inserts; f) contacting the denatured double stranded cDNA inserts produced in step (e) with single-stranded DNAs from another cDNA library under conditions permitting hybridization of the single-stranded DNAs and the double-stranded cDNA inserts; g) separating the hybridized cDNA inserts from the unhybridized inserts; h) generating a cDNA library of the unhybridized inserts, thereby generating a temporally spaced subtracted cDNA library. The cDNAs are then used to monitor cellular differention.

Abstract: A composition for the upregulation of expression of cell antigens, without inducing shedding, which comprises a protein kinase C activator is provided by this invention. Further provided by this invention is a method of detecting and treating tumor cells comprising contacting tumor cells with an effective amount of a protein kinase C activator for the upregulation of expression of antigens of tumor cells, without inducing antigen shedding, and detecting the presence of said antigen or then further contacting said tumor cells with an effective amount of an antibody directed to said antigen.

Abstract: This invention provides a method of generating a subtracted cDNA library of a cell comprising: a) generating a cDNA library of the cell; b) isolating double-stranded DNAs from the cDNA library; c) releasing the double-stranded cDNA inserts from the double-stranded DNAs; d) denaturing the isolated double-stranded cDNA inserts; e) hybridizing the denatured double-stranded cDNA inserts with a labelled single-stranded nucleic acid molecules which are to be subtracted from the cDNA library; and f) separating the hybridized labeled single-stranded nucleic acid molecule from the double-stranded cDNA inserts, thereby generating a subtracted cDNA library of a cell. This invention also provides different uses of the subtracted library.

Abstract: This invention provides a method for identifying differentially expressed nucleic acids between two samples, comprising: a) selecting a first and second nucleic acid sample; b) producing libraries for the first and second nucleic acid sample; c) performing reciprocal subtraction between the libraries to produce two subtracted libraries; d) amplifying the two subtracted libraries; and e) comparing the two amplified subtracted libraries to identify differentially expressed nucleic acids. Also, this invention provides the above-described method, wherein the 3' primer used in the PCR amplification is an oligo dT 3' primer. This invention also provides the above-described methods, wherein the comparing of step e comprises using a gel to separate the nucleic acids from both of the libraries. This invention provides the isolated nucleic acid identified by the the above-described methods, wherein the nucleic was not previously known to be differentially expressed between the two samples.

Abstract: This invention provides a method of isolating a progression suppressor gene which suppresses expression of a gene regulated by a long terminal repeat of a retrovirus comprising: a) introducing DNA containing a long terminal repeat regulated protein kinase C .beta..sub.1 gene into a population of transformed cells; b) treating the cells from step (a) so as to induce the expression of at least one progression suppressor gene and thereby cause a subpopulation of the cells to selectively suppress the expression of the long terminal repeat regulated protein kinase C .beta..sub.1 gene; c) selecting cells which express the progression suppressor gene; d) isolating mRNA from the cells from step (c); e) comparing the mRNA so obtained with mRNA obtained from the uninduced transformed cells so as to identify mRNA only expressed by the cells from step (c); and f) isolating the gene encoding the mRNA in step e) so as to thereby identify the progression suppressor gene.

Abstract: This invention provides a method for preparing a hybridoma cell line which produces an antibody capable of specifically binding to a cell surface-expressed protein which expresses on the surface of one cell type but not the other. This invention also provides a method for preparing a hybridoma cell line which produces an antibody capable of specifically binding to a cell surface-expressed protein. This invention provides a method to prepare a hybridoma cell line which specifically recognizes and binds to a tumor associated antigen associated with a neoplastic, human cell. This invention also provides a method of preparing DNA encoding a cell surface antigen associated with a neoplastic, human cell. This invention further provides an isolated mammalian nucleic acid molecule having the sequence of Prostate Carcinoma Tumor Antigen Gene-1. This invention also provides an isolated mammalian nucleic acid molecules having the sequence of Prostate Tumor Inducing Gene-1.

Abstract: This invention provides a method for reversing the cancerous phenotype of a cancer cell by introducing a nucleic acid having the melanoma differentiation associated gene (mda-7) into the cell under conditions that permit the expression of the gene so as to thereby reverse the cancerous phenotype of the cell. This invention also provides a method for reversing the cancerous phenotype of a cancer cell by introducing the gene product of the above-described gene into the cancerous cell so as to thereby reverse the cancerous phenotype of the cell. This invention also provides a pharmaceutical composition having an amount of a nucleic acid having the melanoma differentiation associated gene (mda-7) or the gene product of a melanoma differentiation associated gene (mda-7) effective to reverse the cancerous phenotype of a cancer cell and a pharmaceutically acceptable carrier.

Abstract: A composition for the upregulation of expression of cell antigens, without inducing shedding, which comprises a protein kinase C activator is provided by this invention. Further provided by this invention is a method of detecting and treating tumor cells comprising contacting tumor cells with an effective amount of a protein kinase C activator for the upregulation of expression of antigens of tumor cells, without inducing antigen shedding, and detecting the presence of said antigen or then further contacting said tumor cells with an effective amount of an antibody directed to said antigen.

Abstract: This invention provides a method of generating a subtracted cDNA library of a cell comprising: a) generating a cDNA library of the cell; b) isolating double-stranded DNAs from the cDNA library; c) releasing the double-stranded cDNA inserts from the double-stranded DNAs; d) denaturing the isolated double-stranded cDNA inserts; e) hybridizing the denatured double-stranded cDNA inserts with a labelled single-stranded nucleic acid molecules which are to be subtracted from the cDNA library; and f) separating the hybridized labeled single-stranded nucleic acid molecule from the double-stranded cDNA inserts, thereby generating a subtracted cDNA library of a cell.