15-Lipoxygenase 2 (15-LOX2) is a recently cloned human lipoxygenase that shows tissue-restricted expression in prostate, lung, skin, and cornea. The protein level and enzymatic activity of 15-LOX2 have been shown to be down-regulated in prostate cancers compared with normal and benign prostate tissues. The biological function of 15-LOX2 and the role of loss of 15-LOX2 expression in prostate tumorigenesis, however, remain unknown. We report the cloning and functional characterization of 15-LOX2 and its three splice variants (termed 15-LOX2sv-a, 15-LOX2sv-b, and 15-LOX2sv-c) from primary prostate epithelial cells. Western blotting with multiple primary prostate cell strains and prostate cancer cell lines reveals that the expression of 15-LOX2 is lost in all prostate cancer cell lines, accompanied by decreased enzymatic activity revealed by liquid chromatography/tandem mass spectrometry analyses. Further experiments show that the loss of 15-LOX2 expression results from transcriptional repression caused by mechanism(s) other than promoter hypermethylation or histone deacetylation. Subsequent functional studies indicate the following: 1) the 15-LOX2 product, 15(S)-hydroxyeicosatetraenoic acid, inhibits prostate cancer cell cycle progression; 2) 15-LOX2 expression in primary prostate epithelial cells is inversely correlated with cell cycle; and 3) restoration of 15-LOX2 expression in prostate cancer cells partially inhibits cell cycle progression. Taken together, these results suggest that 15-LOX2 could be a suppressor of prostate cancer development, which functions by restricting cell cycle progression.
The chemical reactions and pathways involving fatty acids, aliphatic monocarboxylic acids liberated from naturally occurring fats and oils by hydrolysis.
Proc. Natl. Acad. Sci. U.S.A. 94, 6148-6152 (1997)[PubMed:9177185]
The lipoxygenase metabolism of arachidonic acid occurs in specific blood cell types and epithelial tissues and is activated in inflammation and tissue injury. In the course of studying lipoxygenase expression in human skin, we detected and characterized a previously unrecognized enzyme that at least partly accounts for the 15S-lipoxygenase metabolism of arachidonic acid in certain epithelial tissues. The cDNA was cloned from human hair roots, and expression of the mRNA was detected also in prostate, lung, and cornea; an additional 16 human tissues, including peripheral blood leukocytes, were negative for the mRNA. The cDNA encodes a protein of 676 amino acids with a calculated molecular mass of 76 kDa. The amino acid sequence has approximately 40% identity to the known human 5S-, 12S-, and 15S-lipoxygenases. When expressed in HEK 293 cells, the newly discovered enzyme converts arachidonic acid exclusively to 15S-hydroperoxyeicosatetraenoic acid, while linoleic acid is less well metabolized. These features contrast with the previously reported 15S-lipoxygenase, which oxygenates arachidonic acid mainly at C-15, but also partly at C-12, and for which linoleic acid is an excellent substrate. The different catalytic activities and tissue distribution suggest a distinct function for the new enzyme compared with the previously reported human 15S-lipoxygenase.
15-Lipoxygenase 2 (15-LOX2) is a recently cloned human lipoxygenase that shows tissue-restricted expression in prostate, lung, skin, and cornea. The protein level and enzymatic activity of 15-LOX2 have been shown to be down-regulated in prostate cancers compared with normal and benign prostate tissues. The biological function of 15-LOX2 and the role of loss of 15-LOX2 expression in prostate tumorigenesis, however, remain unknown. We report the cloning and functional characterization of 15-LOX2 and its three splice variants (termed 15-LOX2sv-a, 15-LOX2sv-b, and 15-LOX2sv-c) from primary prostate epithelial cells. Western blotting with multiple primary prostate cell strains and prostate cancer cell lines reveals that the expression of 15-LOX2 is lost in all prostate cancer cell lines, accompanied by decreased enzymatic activity revealed by liquid chromatography/tandem mass spectrometry analyses. Further experiments show that the loss of 15-LOX2 expression results from transcriptional repression caused by mechanism(s) other than promoter hypermethylation or histone deacetylation. Subsequent functional studies indicate the following: 1) the 15-LOX2 product, 15(S)-hydroxyeicosatetraenoic acid, inhibits prostate cancer cell cycle progression; 2) 15-LOX2 expression in primary prostate epithelial cells is inversely correlated with cell cycle; and 3) restoration of 15-LOX2 expression in prostate cancer cells partially inhibits cell cycle progression. Taken together, these results suggest that 15-LOX2 could be a suppressor of prostate cancer development, which functions by restricting cell cycle progression.
The chemical reactions and pathways resulting in the formation of leukotriene, a pharmacologically active substance derived from a polyunsaturated fatty acid, such as arachidonic acid.
The chemical reactions and pathways involving lipids, compounds soluble in an organic solvent but not, or sparingly, in an aqueous solvent. Includes fatty acids; neutral fats, other fatty-acid esters, and soaps; long-chain (fatty) alcohols and waxes; sphingoids and other long-chain bases; glycolipids, phospholipids and sphingolipids; and carotenes, polyprenols, sterols, terpenes and other isoprenoids.
15-Lipoxygenase 2 (15-LOX2) is a recently cloned human lipoxygenase that shows tissue-restricted expression in prostate, lung, skin, and cornea. The protein level and enzymatic activity of 15-LOX2 have been shown to be down-regulated in prostate cancers compared with normal and benign prostate tissues. The biological function of 15-LOX2 and the role of loss of 15-LOX2 expression in prostate tumorigenesis, however, remain unknown. We report the cloning and functional characterization of 15-LOX2 and its three splice variants (termed 15-LOX2sv-a, 15-LOX2sv-b, and 15-LOX2sv-c) from primary prostate epithelial cells. Western blotting with multiple primary prostate cell strains and prostate cancer cell lines reveals that the expression of 15-LOX2 is lost in all prostate cancer cell lines, accompanied by decreased enzymatic activity revealed by liquid chromatography/tandem mass spectrometry analyses. Further experiments show that the loss of 15-LOX2 expression results from transcriptional repression caused by mechanism(s) other than promoter hypermethylation or histone deacetylation. Subsequent functional studies indicate the following: 1) the 15-LOX2 product, 15(S)-hydroxyeicosatetraenoic acid, inhibits prostate cancer cell cycle progression; 2) 15-LOX2 expression in primary prostate epithelial cells is inversely correlated with cell cycle; and 3) restoration of 15-LOX2 expression in prostate cancer cells partially inhibits cell cycle progression. Taken together, these results suggest that 15-LOX2 could be a suppressor of prostate cancer development, which functions by restricting cell cycle progression.
15-Lipoxygenase 2 (15-LOX2) is a recently cloned human lipoxygenase that shows tissue-restricted expression in prostate, lung, skin, and cornea. The protein level and enzymatic activity of 15-LOX2 have been shown to be down-regulated in prostate cancers compared with normal and benign prostate tissues. The biological function of 15-LOX2 and the role of loss of 15-LOX2 expression in prostate tumorigenesis, however, remain unknown. We report the cloning and functional characterization of 15-LOX2 and its three splice variants (termed 15-LOX2sv-a, 15-LOX2sv-b, and 15-LOX2sv-c) from primary prostate epithelial cells. Western blotting with multiple primary prostate cell strains and prostate cancer cell lines reveals that the expression of 15-LOX2 is lost in all prostate cancer cell lines, accompanied by decreased enzymatic activity revealed by liquid chromatography/tandem mass spectrometry analyses. Further experiments show that the loss of 15-LOX2 expression results from transcriptional repression caused by mechanism(s) other than promoter hypermethylation or histone deacetylation. Subsequent functional studies indicate the following: 1) the 15-LOX2 product, 15(S)-hydroxyeicosatetraenoic acid, inhibits prostate cancer cell cycle progression; 2) 15-LOX2 expression in primary prostate epithelial cells is inversely correlated with cell cycle; and 3) restoration of 15-LOX2 expression in prostate cancer cells partially inhibits cell cycle progression. Taken together, these results suggest that 15-LOX2 could be a suppressor of prostate cancer development, which functions by restricting cell cycle progression.
15-Lipoxygenase 2 (15-LOX2) is a recently cloned human lipoxygenase that shows tissue-restricted expression in prostate, lung, skin, and cornea. The protein level and enzymatic activity of 15-LOX2 have been shown to be down-regulated in prostate cancers compared with normal and benign prostate tissues. The biological function of 15-LOX2 and the role of loss of 15-LOX2 expression in prostate tumorigenesis, however, remain unknown. We report the cloning and functional characterization of 15-LOX2 and its three splice variants (termed 15-LOX2sv-a, 15-LOX2sv-b, and 15-LOX2sv-c) from primary prostate epithelial cells. Western blotting with multiple primary prostate cell strains and prostate cancer cell lines reveals that the expression of 15-LOX2 is lost in all prostate cancer cell lines, accompanied by decreased enzymatic activity revealed by liquid chromatography/tandem mass spectrometry analyses. Further experiments show that the loss of 15-LOX2 expression results from transcriptional repression caused by mechanism(s) other than promoter hypermethylation or histone deacetylation. Subsequent functional studies indicate the following: 1) the 15-LOX2 product, 15(S)-hydroxyeicosatetraenoic acid, inhibits prostate cancer cell cycle progression; 2) 15-LOX2 expression in primary prostate epithelial cells is inversely correlated with cell cycle; and 3) restoration of 15-LOX2 expression in prostate cancer cells partially inhibits cell cycle progression. Taken together, these results suggest that 15-LOX2 could be a suppressor of prostate cancer development, which functions by restricting cell cycle progression.
15-Lipoxygenase 2 (15-LOX2) is a recently cloned human lipoxygenase that shows tissue-restricted expression in prostate, lung, skin, and cornea. The protein level and enzymatic activity of 15-LOX2 have been shown to be down-regulated in prostate cancers compared with normal and benign prostate tissues. The biological function of 15-LOX2 and the role of loss of 15-LOX2 expression in prostate tumorigenesis, however, remain unknown. We report the cloning and functional characterization of 15-LOX2 and its three splice variants (termed 15-LOX2sv-a, 15-LOX2sv-b, and 15-LOX2sv-c) from primary prostate epithelial cells. Western blotting with multiple primary prostate cell strains and prostate cancer cell lines reveals that the expression of 15-LOX2 is lost in all prostate cancer cell lines, accompanied by decreased enzymatic activity revealed by liquid chromatography/tandem mass spectrometry analyses. Further experiments show that the loss of 15-LOX2 expression results from transcriptional repression caused by mechanism(s) other than promoter hypermethylation or histone deacetylation. Subsequent functional studies indicate the following: 1) the 15-LOX2 product, 15(S)-hydroxyeicosatetraenoic acid, inhibits prostate cancer cell cycle progression; 2) 15-LOX2 expression in primary prostate epithelial cells is inversely correlated with cell cycle; and 3) restoration of 15-LOX2 expression in prostate cancer cells partially inhibits cell cycle progression. Taken together, these results suggest that 15-LOX2 could be a suppressor of prostate cancer development, which functions by restricting cell cycle progression.
15-Lipoxygenase 2 (15-LOX2) is a recently cloned human lipoxygenase that shows tissue-restricted expression in prostate, lung, skin, and cornea. The protein level and enzymatic activity of 15-LOX2 have been shown to be down-regulated in prostate cancers compared with normal and benign prostate tissues. The biological function of 15-LOX2 and the role of loss of 15-LOX2 expression in prostate tumorigenesis, however, remain unknown. We report the cloning and functional characterization of 15-LOX2 and its three splice variants (termed 15-LOX2sv-a, 15-LOX2sv-b, and 15-LOX2sv-c) from primary prostate epithelial cells. Western blotting with multiple primary prostate cell strains and prostate cancer cell lines reveals that the expression of 15-LOX2 is lost in all prostate cancer cell lines, accompanied by decreased enzymatic activity revealed by liquid chromatography/tandem mass spectrometry analyses. Further experiments show that the loss of 15-LOX2 expression results from transcriptional repression caused by mechanism(s) other than promoter hypermethylation or histone deacetylation. Subsequent functional studies indicate the following: 1) the 15-LOX2 product, 15(S)-hydroxyeicosatetraenoic acid, inhibits prostate cancer cell cycle progression; 2) 15-LOX2 expression in primary prostate epithelial cells is inversely correlated with cell cycle; and 3) restoration of 15-LOX2 expression in prostate cancer cells partially inhibits cell cycle progression. Taken together, these results suggest that 15-LOX2 could be a suppressor of prostate cancer development, which functions by restricting cell cycle progression.
The process whose specific outcome is the progression of the prostate gland over time, from its formation to the mature structure. The prostate gland is a partly muscular, partly glandular body that is situated near the base of the mammalian male urethra and secretes an alkaline viscid fluid which is a major constituent of the ejaculatory fluid.
15-Lipoxygenase 2 (15-LOX2) is a recently cloned human lipoxygenase that shows tissue-restricted expression in prostate, lung, skin, and cornea. The protein level and enzymatic activity of 15-LOX2 have been shown to be down-regulated in prostate cancers compared with normal and benign prostate tissues. The biological function of 15-LOX2 and the role of loss of 15-LOX2 expression in prostate tumorigenesis, however, remain unknown. We report the cloning and functional characterization of 15-LOX2 and its three splice variants (termed 15-LOX2sv-a, 15-LOX2sv-b, and 15-LOX2sv-c) from primary prostate epithelial cells. Western blotting with multiple primary prostate cell strains and prostate cancer cell lines reveals that the expression of 15-LOX2 is lost in all prostate cancer cell lines, accompanied by decreased enzymatic activity revealed by liquid chromatography/tandem mass spectrometry analyses. Further experiments show that the loss of 15-LOX2 expression results from transcriptional repression caused by mechanism(s) other than promoter hypermethylation or histone deacetylation. Subsequent functional studies indicate the following: 1) the 15-LOX2 product, 15(S)-hydroxyeicosatetraenoic acid, inhibits prostate cancer cell cycle progression; 2) 15-LOX2 expression in primary prostate epithelial cells is inversely correlated with cell cycle; and 3) restoration of 15-LOX2 expression in prostate cancer cells partially inhibits cell cycle progression. Taken together, these results suggest that 15-LOX2 could be a suppressor of prostate cancer development, which functions by restricting cell cycle progression.
15-Lipoxygenase 2 (15-LOX2) is a recently cloned human lipoxygenase that shows tissue-restricted expression in prostate, lung, skin, and cornea. The protein level and enzymatic activity of 15-LOX2 have been shown to be down-regulated in prostate cancers compared with normal and benign prostate tissues. The biological function of 15-LOX2 and the role of loss of 15-LOX2 expression in prostate tumorigenesis, however, remain unknown. We report the cloning and functional characterization of 15-LOX2 and its three splice variants (termed 15-LOX2sv-a, 15-LOX2sv-b, and 15-LOX2sv-c) from primary prostate epithelial cells. Western blotting with multiple primary prostate cell strains and prostate cancer cell lines reveals that the expression of 15-LOX2 is lost in all prostate cancer cell lines, accompanied by decreased enzymatic activity revealed by liquid chromatography/tandem mass spectrometry analyses. Further experiments show that the loss of 15-LOX2 expression results from transcriptional repression caused by mechanism(s) other than promoter hypermethylation or histone deacetylation. Subsequent functional studies indicate the following: 1) the 15-LOX2 product, 15(S)-hydroxyeicosatetraenoic acid, inhibits prostate cancer cell cycle progression; 2) 15-LOX2 expression in primary prostate epithelial cells is inversely correlated with cell cycle; and 3) restoration of 15-LOX2 expression in prostate cancer cells partially inhibits cell cycle progression. Taken together, these results suggest that 15-LOX2 could be a suppressor of prostate cancer development, which functions by restricting cell cycle progression.
Protein involved in the synthesis of leukotrienes, eicosanoid hormones first isolated from leukocytes. They are thought to mediate the allergic response that causes lung constriction and muscle contraction in asthma.
A reference proteome is a set of protein sequences derived from a complete proteome which constitutes a defined standard for a particular user community. Reference proteomes are manually defined according to a number of criteria. They cover the proteomes of well- studied model organisms and other proteomes of interest for biomedical and biotechnological research. Reference proteomes have been selected to provide broad coverage of the tree of life, and constitute a representative cross-section of the taxonomic diversity to be found within UniProtKB.