Pancreatic ductal adenocarcinoma(PDAC) has the poorest prognosis of all malignancies and is largely resistant to standard therapy. Novel treatments against PDAC are desperately needed. Anti-Gal is the most abundant na...Pancreatic ductal adenocarcinoma(PDAC) has the poorest prognosis of all malignancies and is largely resistant to standard therapy. Novel treatments against PDAC are desperately needed. Anti-Gal is the most abundant natural antibody in humans,comprising about 1% of immunoglobulins and is also naturally produced in apes and Old World monkeys. The anti-Gal ligand is a carbohydrate antigen called "α-gal epitopes" with the structure Galα1-3Galβ1-4Glc NAc-R. These epitopes are expressed as major carbohydrate antigens in non-primate mammals,prosimians,and New World monkeys. Anti-Gal is exploited in cancer vaccines to increase the immunogenicity of antigen-presenting cells(APCs). Cancer cells or PDAC tumor lysates are processed to express α-gal epitopes. Vaccination with these components results in in vivo opsonization by anti-Gal Ig G in PDAC patients. The Fc portion of the vaccine-bound anti-Gal interacts with Fcγ receptors of APCs,inducing uptake of the vaccine components,transport of the vaccine tumor membranes to draining lymph nodes,and processing and presentation of tumor-associated antigens(TAAs). Cancer vaccines expressing α-gal epitopes elicit strong antibody production against multiple TAAs contained in PDAC cells and induce activation of multiple tumor-specific T cells. Here,we review new areas of clinical importance related to the α-gal epitope/anti-Gal antibody reaction and the advantages in immunotherapy against PDAC.展开更多
From the 1-BuOH-soluble fraction of a MeOH extract of the leaves of Symplocos cochinchinensis var. philippinensis, 12 compounds were isolated. Spectroscopic analyses of compounds 1 - 3 established their structures to ...From the 1-BuOH-soluble fraction of a MeOH extract of the leaves of Symplocos cochinchinensis var. philippinensis, 12 compounds were isolated. Spectroscopic analyses of compounds 1 - 3 established their structures to be megastig-mane glycosides, named symplocosionosides A-C. The absolute structure of 1 was determined by the modified Mosher’s method. Compound 4 was found to be a neolignan glucoside and named symplocosneolignan. The structures of com-pounds 5 and 6, named symplocosins A and B, were elucidated to be the saponins of hederagenin sugar esters. The structures of the remaining known compounds (7 - 12) were identified by comparison of spectroscopic data with those reported in the literature.展开更多
From the branches of Tabebuia chrysotricha (Bignoniaceae), two lignan glycosides (1, 2) and two phenolic compound glycosides (3, 4) were isolated, along with 15 known compounds (5 - 19). The structures of the new comp...From the branches of Tabebuia chrysotricha (Bignoniaceae), two lignan glycosides (1, 2) and two phenolic compound glycosides (3, 4) were isolated, along with 15 known compounds (5 - 19). The structures of the new compounds were elucidated on the basis of spectroscopic evidence and those of the known compounds were identified by comparison of spectroscopic data with those reported in the literature. The DPPH radical-scavenging activity was assayed for the compounds isolated, the aryltetralin-type lignans showing moderate activity.展开更多
From the branches of Microtropis japonica (Celastraceae), seven phenolic alcohol glucosides, named microtropins J-P (1-7), were isolated. The 6-position of glucose was esterified with 2-ethyl-2,3-dihydroxybutyric acid...From the branches of Microtropis japonica (Celastraceae), seven phenolic alcohol glucosides, named microtropins J-P (1-7), were isolated. The 6-position of glucose was esterified with 2-ethyl-2,3-dihydroxybutyric acid. Microtropin K (2) was hydrolyzed under a mild basic condition to give methyl (2S,3R)-2-ethyl-2,3-dihydroxybutyrate, whose absolute structure was determined by the comparison of NMR data and the optical rotation value with that reported.展开更多
From the leaves of a Thai medicinal plant, Croton sublyratus, collected in Thailand, two new cembrane-type diterpenoids, named sublylactones A and B, and a phenolic compound were isolated from the EtOAc-soluble fracti...From the leaves of a Thai medicinal plant, Croton sublyratus, collected in Thailand, two new cembrane-type diterpenoids, named sublylactones A and B, and a phenolic compound were isolated from the EtOAc-soluble fraction of a MeOH extract. Their structures were elucidated on the basis of spectroscopic evidence.展开更多
基金Supported by Ministry of Education,Sports and Culture of Japan to M.T.,No.25462129
文摘Pancreatic ductal adenocarcinoma(PDAC) has the poorest prognosis of all malignancies and is largely resistant to standard therapy. Novel treatments against PDAC are desperately needed. Anti-Gal is the most abundant natural antibody in humans,comprising about 1% of immunoglobulins and is also naturally produced in apes and Old World monkeys. The anti-Gal ligand is a carbohydrate antigen called "α-gal epitopes" with the structure Galα1-3Galβ1-4Glc NAc-R. These epitopes are expressed as major carbohydrate antigens in non-primate mammals,prosimians,and New World monkeys. Anti-Gal is exploited in cancer vaccines to increase the immunogenicity of antigen-presenting cells(APCs). Cancer cells or PDAC tumor lysates are processed to express α-gal epitopes. Vaccination with these components results in in vivo opsonization by anti-Gal Ig G in PDAC patients. The Fc portion of the vaccine-bound anti-Gal interacts with Fcγ receptors of APCs,inducing uptake of the vaccine components,transport of the vaccine tumor membranes to draining lymph nodes,and processing and presentation of tumor-associated antigens(TAAs). Cancer vaccines expressing α-gal epitopes elicit strong antibody production against multiple TAAs contained in PDAC cells and induce activation of multiple tumor-specific T cells. Here,we review new areas of clinical importance related to the α-gal epitope/anti-Gal antibody reaction and the advantages in immunotherapy against PDAC.
文摘From the 1-BuOH-soluble fraction of a MeOH extract of the leaves of Symplocos cochinchinensis var. philippinensis, 12 compounds were isolated. Spectroscopic analyses of compounds 1 - 3 established their structures to be megastig-mane glycosides, named symplocosionosides A-C. The absolute structure of 1 was determined by the modified Mosher’s method. Compound 4 was found to be a neolignan glucoside and named symplocosneolignan. The structures of com-pounds 5 and 6, named symplocosins A and B, were elucidated to be the saponins of hederagenin sugar esters. The structures of the remaining known compounds (7 - 12) were identified by comparison of spectroscopic data with those reported in the literature.
文摘From the branches of Tabebuia chrysotricha (Bignoniaceae), two lignan glycosides (1, 2) and two phenolic compound glycosides (3, 4) were isolated, along with 15 known compounds (5 - 19). The structures of the new compounds were elucidated on the basis of spectroscopic evidence and those of the known compounds were identified by comparison of spectroscopic data with those reported in the literature. The DPPH radical-scavenging activity was assayed for the compounds isolated, the aryltetralin-type lignans showing moderate activity.
文摘From the branches of Microtropis japonica (Celastraceae), seven phenolic alcohol glucosides, named microtropins J-P (1-7), were isolated. The 6-position of glucose was esterified with 2-ethyl-2,3-dihydroxybutyric acid. Microtropin K (2) was hydrolyzed under a mild basic condition to give methyl (2S,3R)-2-ethyl-2,3-dihydroxybutyrate, whose absolute structure was determined by the comparison of NMR data and the optical rotation value with that reported.
文摘From the leaves of a Thai medicinal plant, Croton sublyratus, collected in Thailand, two new cembrane-type diterpenoids, named sublylactones A and B, and a phenolic compound were isolated from the EtOAc-soluble fraction of a MeOH extract. Their structures were elucidated on the basis of spectroscopic evidence.
