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H Kagechika

Publications and source records attributed to H Kagechika.

At least 55 records · Page 3Linked to original sources
PubMed1992

Base-catalyzed isomerization of retinoic acid. Synthesis and differentiation-inducing activities of 14-alkylated all-trans-, 13-cis-, and 20,14-retro-retinoic acids.

Retinoic acid (1) is isomerized regioselectively by excess amounts of lithium diisopropylamide (LDA) to give 20,14-retro-retinoic acid (3). Alkylation of the intermediate dianion of retinoic acid gave 14-alkylated derivatives of 3. By isomerization of the alkylated retro isomers under basic conditions, several 14-alkyl-all-trans- and -13-cis-retinoic acids were synthesized. The retinoidal activities of these derivatives were examined, based on the ability to induce differentiation of human promyelocytic leukemia cell line HL-60. 20,14-retro-Retinoic acid (3) is 1/50 as active as retinoic acid (1). Although 14-methyl-20,14-retro-retinoic acid (4) is as active as 3, the introduction of a 14-methyl group into all-trans- and 13-cis-retinoic acid resulted in decreased activity. Introduction of bulkier alkyl groups at the C-14 position caused the disappearance of the activity.

Alkylation↗
PubMed1991

Fluorescent probes for retinoic acid receptors: molecular measures for the ligand binding pocket.

Two fluorescent probes for nuclear retinoic acid receptors (RARs) have been developed, both containing a biologically active retinoid moiety and a fluorescent dansyl moiety, but differing in the length of the spacer arm connecting the two moieties. Both probes bind RARs at their retinoid-binding sites, revealing the usefulness of the compounds as fluorescent RAR probes. By measuring the specific increase of the probes' fluorescence intensity caused by the binding to RARs, the linearized length of the RAR's retinoid-binding pocket could be estimated.

Binding, Competitive↗
PubMed1991

Fluorescent and photoaffinity labeling probes for retinoic acid receptors.

A fluorescent probe for retinoid receptors (RARs) was designed and prepared. The probe consists of a retinoid moiety and a dansyl moiety, i.e., 2-[3-(5-dimethylaminonaphthalene-1-sulfonyl)- aminopropyl-1-oxy]-4-[(5,6,7,8-tetrahydro-5,5,8,8-tetramethyl-2- naphthalenyl)carboxamido]benzoic acid: DAM-3. DAM-3 specifically bound RARs. Additionally, a photoreactive RAR fluorescent probe was designed and prepared, i.e., 2-[3-(5-azidonaphthalene- 1-sulfonyl)aminopropyl-1-oxy]-4-[(5,6,7,8-tetrahydro-5,5,8,8- tetramethyl-2-naphthalenyl)carboxamido]benzoic acid (ADAM-3). ADAM-3 irreversibly and specifically bound RARs using ultraviolet irradiation.

Affinity Labels↗
PubMed1990

Expression of retinoic acid receptor genes and the ligand-binding selectivity of retinoic acid receptors (RAR's).

Retinoids of a structurally new type, 4-(5,6,7,8-tetrahydro-5,5,8,8-tetramethyl-2-naphthalenylcarbamoyl)benzoic acid (Am80) and (E)-4-[3-(3,5-di-tert-butylphenyl)-3-oxo-1-propenyl]-benzoic acid (Ch55), were used for the investigation of retinoid receptors in some human cell lines. Previously, using these retinoids, we have established that HL-60 cells possess two retinoid receptors, RAR-alpha and RAR-beta. In this paper, we report coexpression of RAR-alpha- and RAR-beta-genes established by Northern analysis. Further, the binding selectivity of the RAR products toward all-trans-retinoic acid (RA), Am80 and Ch55 was studied by filter binding assay. The affinity of the ligands toward RAR-alpha decreased in the order of Ch55 greater than RA greater than Am80. The affinity of the ligands toward RAR-beta decreased in the order of Ch55 greater than Am80 greater than RA.

Blotting, Northern↗
PubMed1990

Synthetic retinoids, retinobenzoic acids, Am80, Am580 and Ch55 regulate morphogenesis in chick limb bud.

The retinobenzoic acids Am80, Am580 and Ch55 are synthetic stable analogs of retinoic acid (RA), and show very strong differentiation-inducing activity in human myelogeneous leukemia cell line HL-60. To examine the effects of these synthetic retinoids on limb pattern formation, AG1-X2 beads containing these retinoids were applied to the anterior margin of stage 19-20 chick wing buds. By implanting the beads with 1 microgram/ml retinoids, normal wings were formed and extra digits 2 or 32 were rarely formed. As the retinoid concentrations increased from 10 micrograms/ml to 100 micrograms/ml duplicated limbs 3234, 43234, 432234, 4334 were progressively produced. At higher concentrations, 1 mg/ml, the wings often truncated, although duplication occurred in some embryos. These synthetic analogs seem to have the same degree of morphogenetic potential as RA, since the activity index of these retinoids was similar to that of RA. Since these synthetic retinoids hardly bind to CRABP (cellular retinoic acid-binding protein), it may be possible that the retinoids and RA may affect limb-pattern formation without the interaction with CRABP. It is known that limb buds cannot develop distal structures when the posterior region including all ZPA (zone of polarizing activity) is removed. When beads containing the above mentioned retinoids were implanted to the anterior margin of wing buds from which the posterior one third region including all ZPA had been removed, distal growth of the wing buds and the formation of digit elements were observed. Some of the wing buds produced a completely reverse digit pattern 432. From these results, we discussed the roles of RA in limb development and pattern formation.

Animals↗
PubMed1990

Retinobenzoic acids. 5. Retinoidal activities of compounds having a trimethylsilyl or trimethylgermyl group(s) in human promyelocytic leukemia cells HL-60.

The retinoidal activities of trimethylsilyl or trimethylgermyl-containing retinobenzoic acids are discussed on the basis of differentiation-inducing activity on human promyelocytic leukemia cells HL-60. Compounds with a trimethylsilyl or trimethylgermyl group at the meta position of the generic formula 2 have more potent activities than the corresponding retinobenzoic acids with a m-tert-butyl group. Compounds having two m-trimethylsilyl or -trimethylgermyl groups also have strong activities, and (E)-4-[3-[3,5-bis(trimethylsilyl)phenyl]-3-oxo-1-propenyl]benzoic acid (22, Ch55S) and (E)-4-[3-[3,5-bis(trimethylgermyl)phenyl]-3-oxo-1- propenyl]benzoic acid (35, Ch55G) are more active than retinoic acid by 1 order of magnitude. However, in the para-substituted chalcone derivatives, the replacement of a tert-butyl group (49, Ch40) with a trimethylsilyl (27, Ch40S) or a trimethylgermyl (30, Ch40G) group caused the disappearance of the activity.

Antineoplastic Agents↗
PubMed1989

Retinobenzoic acids. 2. Structure-activity relationships of chalcone-4-carboxylic acids and flavone-4'-carboxylic acids.

The structure-activity relationships of (E)-chalcone-4-carboxylic acids, which are retinoidal benzoic acids represented by R-Ph-X-Ph-COOH (4, X = -COCH = CH-), are discussed on the basis of differentiation-inducing activity on human promyelocytic leukemia cells HL-60. The activity was increased by the substitution of a bulky alkyl group(s) (R), and among such compounds, (E)-4-[3-(3,5-di-tert-butylphenyl)-3-oxo-1-propenyl]benzoic acid (Ch55) and (E)-4-[3-oxo-3-(5,6,7,8-tetrahydro-5,5,8,8-tetramethyl-2-naphthalenyl)-1 -propenyl]benzoic acid (Ch80) are several times more active than retinoic acid. Though the stable conformer of chalcone derivatives is linear (s-cis form), the conformationally restricted analogue 4-(6,7,8,9-tetrahydro-6,6,9,9-tetramethyl-4H-4-oxonaphtho[2,3-b]py ran-2-yl)benzoic acid (Fv80) is more active than Ch80. While the effect of introduction of an oxygen atom varied, 4-[1-hydroxy-3-oxo-3-(5,6,7,8-tetrahydro-3-hydroxy-5,5,8,8-tetramethyl-2 - naphthalenyl)-1-propenyl]benzoic acid (Re80), regarded as a derivative of Ch80 with two additional hydroxyl groups, has very strong activity.

Carboxylic Acids↗
PubMed1989

Retinobenzoic acids. 3. Structure-activity relationships of retinoidal azobenzene-4-carboxylic acids and stilbene-4-carboxylic acids.

Alkyl-substituted azobenzene-4-carboxylic acids are potent differentiation inducers of human promyelocytic leukemia cell line HL-60 to mature granulocytes. Their structure-activity relationships are very similar to those of other retinoidal benzoic acids which are generally represented by 4 and named retinobenzoic acids. The structure-activity relationships of azobenzenecarboxylic acids can also be applied to the known retinoid TTNPB (3). Thus, (E)-4-[2-(3,4-diisopropylphenyl)-1-propenyl]benzoic acid (St30 (28] and (E)-4-[2-(3-tert-butylphenyl)ethenyl]benzoic acid (St40 (29], the acyclic alkyl analogues of TTNPB, are nearly as active as retinoic acid. Among the oxidatively derived compounds (Az90, Ep series and Ox series) of azobenzene- or stilbenecarboxylic acids, Az90 (71) and Ep80 (61) have strong activities. However, all the bishydroxylated derivatives of TTNPB are inactive, while a diketo analogue Ox580 (69) has only weak potency. The activities of conformationally restricted compounds of TTNPB offer some information on the stereochemistry of the active form of these retinoidal compounds.

Benzoates↗
PubMed1989

Retinobenzoic acids. 4. Conformation of aromatic amides with retinoidal activity. Importance of trans-amide structure for the activity.

N-Methylation of two retinoidal amide compounds, 4-[(5,6,7,8-tetrahydro-5,5,8,8-tetramethyl-2-naphthalenyl)carbamoyl]benz oic acid (3, Am80) and 4-[[(5,6,7,8-tetrahydro-5,5,8,8-tetramethyl-2- naphthalenyl)carbonyl]amino]benzoic acid (5, Am580), resulted in the disappearance of their potent differentiation-inducing activity on human promyelocytic leukemia cell line HL-60. Studies with 1H NMR and UV spectroscopy indicated that large conformational differences exist between the active secondary amides and the inactive N-methyl amides. From a comparison of the spectroscopic results of these amides with those of stilbene derivatives, the conformations of the active amides are expected to resemble that of (E)-stilbene, whereas the inactive amides resemble the Z isomer: 3 (Am80) and 5 (Am580) have a trans-amide bond and their whole structures are elongated, while the N-methylated compounds [4 (Am90) and 6 (Am590)] have a cis-amide bond, resulting in the folding of the two benzene rings. These structures in the crystals were related to those in solution by 13C NMR spectroscopic comparison between the two phases (solid and solution).

Amides↗
PubMed1989

The retinoic acid receptors alpha and beta are expressed in the human promyelocytic leukemia cell line HL-60.

The human promyelocytic leukemia cell line HL-60 can be induced to differentiate into granulocytes upon exposure to retinoids. Previously we have shown that extracts of undifferentiated HL-60 cells possess a specific retinoid-binding activity (RSBP-1) corresponding to an approximate 95 kilodalton (kDa) protein as determined by size-exclusion chromatography. We now extend these observations to reveal a second approximate 95 kDa retinoic acid-binding component (RSBP-2), which is separable from RSBP-1 using anion exchange chromatography. We further show that the chromatographic properties of RSBP-1 and RSBP-2 are identical to those found for the retinoid-binding activities present in extracts of HeLa cells transfected with the human retinoic acid receptor (RAR) expression vectors RAR-beta phi and RAR-alpha phi, respectively. Moreover, an antiserum preparation directed against RAR-beta selectively immunoprecipitated both the retinoid-binding activity in extracts of HeLa cells transfected with RAR-beta phi and that corresponding to RSBP-1 in HL-60 cell extracts. Similarly, an antiserum preparation directed against RAR-alpha immunoprecipitated the retinoid-binding activity in extracts from RAR-alpha phi transfected HeLa cell as well as that corresponding to RSBP-2 in HL-60 cell extracts. Using these antisera, Western blot analyses of extracts from HL-60 cells, and from HeLa cells transfected with either RAR-alpha phi or RAR-beta phi, confirmed that RSBP-2 and RSBP-1 are identical to RAR-alpha and RAR-beta, respectively. However, RAR-alpha, RAR-beta, RSBP-1, and RSBP-2 appeared as an approximate 51 kDa species in sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis in contrast with an apparent approximate 95 k mol wt as estimated from size-exclusion chromatography in the presence of 0.6 M KCl.(ABSTRACT TRUNCATED AT 250 WORDS)

Antibodies↗
PubMed1988

Affinity gels for purification of retinoid-specific binding protein (RSBP).

Retinoids are defined as compounds which elicit specific biological effects such as control of cell growth and cell differentiation by binding to a specific receptor. Recently, we demonstrated the presence of a protein (RSBP) which satisfies the criteria for the retinoid receptor. For purification of RSBP, we prepared two types of affinity gels with retinoidal ligands (Gel-Am and Gel-Ch) based on synthetic retinobenzoic acids which possess very potent retinoidal activities. RSBP in the crude fraction extracted from cultured cells could be purified about 300-fold by affinity column chromatography using these affinity gels.

Binding, Competitive↗
PubMed1988

Inhibition of ornithine decarboxylase induction by retinobenzoic acids in relation to their binding affinities to cellular retinoid-binding proteins.

Retinobenzoic acids induce differentiation of human promyelocytic leukemia cells (HL-60). Like retinoic acid, 14 retinobenzoic acids inhibited the induction of ornithine decarboxylase (ODC) by teleocidin in mouse skin. The mechanism(s) of inhibition of ODC induction by 7 retinobenzoic acids, Am 80, Am 81, Am 580, Am 590, Am 68, Sa 80, and Ch 55 was compared with those by all-trans-retinoic acid and the arotinoid compound 19. Application of 114 nmol of Am 80, Am 81, Am 580, Am 590, Am 68, Sa 80, or Ch 55, 10 min before 11.4 nmol of teleocidin, resulted in 76.7%, 82.0%, 76.2%, 28.3%, 48.4%, 58.6%, and 85.1% inhibition of ODC induction, respectively. Since all-trans-retinoic acid and compound 19 were also inhibitory, we determined whether retinobenzoic acids bind to cellular retinoic acid-binding protein (CRABP) isolated from bovine adrenal glands. Am 80 and Am 580 inhibited the specific binding of 3H-retinoic acid to CRABP, but also showed less affinity than authentic unlabeled retinoic acid and compound 19. Am 81, Am 590, Am 68, Sa 80, and Ch 55 at up to 10 microM were not effective competitors of the binding of either 3H-retinoic acid or 3H-retinol. These results suggest that the inhibition of ODC induction can be mediated by pathways that do not involve CRABP or the cellular retinol-binding protein.

Animals↗
PubMed1988

Retinobenzoic acids. 1. Structure-activity relationships of aromatic amides with retinoidal activity.

Two types of aromatic amides, terephthalic monoanilides and (arylcarboxamido)benzoic acids, have been shown to possess potent retinoidal activities and can be classified as retinoids. The structure-activity relationships of these amides are discussed on the basis of differentiation-inducing activity on human promyelocytic leukemia cells HL-60. In generic formula 4 (X = NHCO or CONH), the necessary factors to elicit the retinoidal activities are a medium-sized alkyl group (isopropyl, tert-butyl, etc.) at the meta position and a carboxyl group at the para position of the other benzene ring. The bonding of the amide structure can be reversed, this moiety apparently having the role of locating the two benzene rings at suitable positions with respect to each other. Substitution at the ring position ortho to the amide group or N-methylation of the amide group caused loss of activity, presumably owing to the resultant change of conformation. It is clear that the mutual orientation of the benzylic methyl group(s) and the carboxyl group and their distance apart are essential factors determining the retinoidal activity. Among the synthesized compounds, 4-[(5,6,7,8-tetrahydro-5,5,8,8-tetramethyl-2-naphthalenyl)carbamoyl]benz oic acid (Am80) and 4-[(5,6,7,8-tetrahydro-5,5,8,8-tetramethyl-2-naphthalenyl)carboxamido] benzoic acid (Am580) were several times more active than retinoic acid in the assay. They are structurally related to retinoic acid, as is clear from the biological activity of the hybrid compounds (M2 and R2).

Amides↗
PubMed1988

Specific uptake of retinoids into human promyelocytic leukemia cells HL-60 by retinoid-specific binding protein: possibly the true retinoid receptor.

The uptake of all-trans-retinoic acid (RA) and two new retinoids [4-(5,6,7,8-tetrahydro-5,5,8,8-tetramethyl-2-naphthalenylcarbamoyl )benzoic acid (Am80) and (E)-4-[3-(3,5-di-tert-butylphenyl)-3-oxo-1-propenyl]benzoic acid (Ch55)] by HL-60 human promyelocytic leukemia cells was investigated. For the investigation, [3H]RA and [3H]Am80 with high specific radioactivities (more than 50 Ci/mmol) were used. [3H]Am80 was prepared by hydrogenolysis of the corresponding chlorinated derivative of Am80 with tritium gas. The retinoids RA, Am80 and Ch55 were efficiently taken up by HL-60 cells, and induced differentiation of the cells into mature granulocytes. The specific bindings (uptake) of RA, Am80 and Ch55 (the bindings inhibited competitively by the other two retinoids) by HL-60 cells were due to a newly detected binding protein. The protein that bound specifically to RA appeared identical to that which bound specifically to Am80 by high-performance liquid chromatography (HPLC), and was named retinoid-specific binding protein (RSBP). One HL-60 cell was found to contain about 1500 molecules of RSBP distributed between the nuclear fraction and cytosolic fraction in proportions of about 4:1. The bindings of the three retinoids (RA, Am80 and Ch55) to RSBP (i.e., formation of retinoid-RSBP complexes) greatly enhanced the affinity of RSBP for the nuclei. The apparent molecular weight of RSBP was estimated to be 95,000 daltons by size exclusion HPLC. The association constants (Ka) of RSBP were calculated to be 2.4 X 10(10) M-1 for RA and 4.4 X 10(10) M-1 for Am80 from Scatchard plots. The bindings of RA, Am80 and Ch55 to RSBP were mutually competitive, indicating that the binding sites for RA, Am80 and Ch55 were identical. The very high affinities of these retinoids for RSBP (Ka's of the order of 10(10) M-1) correspond to the effective concentrations of these retinoids in HL-60 cell culture medium for induction of differentiation of the cells. The mutually competitive bindings of these retinoids strongly support the idea that RSBP is the true receptor of retinoids.

Benzoates↗
PubMed1988

[Recent advances in retinoids studies].

Retinoids are defined as the compounds which elicit the specific biological responses through binding or activating the specific receptor(s). Retinoids modulate the cellular differentiation and proliferation in many types of cells. A series of retinoidal benzoic acids, named retinobenzoic acids, have potent activities on human promyelocytic leukemia cells, HL-60, and other assay systems. Among them, Am80, AM580 and Ch55 are more active than retinoic acid in most cases. As these compounds possess quite different structures or physicochemical properties from retinoic acid or conventional retinoids, they are expected to be applied clinically for the treatments of the diseases in oncology and dermatology. Recently, progresses on the mechanistic studies on retinoidal actions have been reported. One of them is isolation and cloning of human retinoic acid-receptors and the mechanism of retinoidal action was concluded that the retinoid-receptor complex interact directly with DNA to regulate the expression of the gene, like steroid hormone. The other is the establishment of the presence of the retinoid-specific-binding protein (RSBP) by the use of our retinobenzoic acids as the probe.

Animals↗
PubMed1987

New benzoic acid derivatives with retinoid activity: lack of direct correlation between biological activity and binding to cellular retinoic acid binding protein.

In this paper the biological activity of several newly synthesized benzoic acid derivatives of the Am- and Ch- series, which are structurally different from retinoic acid and arotinoids, was examined. These compounds inhibit squamous cell differentiation of rabbit tracheal epithelial cells in vitro as indicated by the inhibition of transglutaminase Type I and cholesterol 3-sulfate levels. In contrast to the inhibition of differentiation in rabbit tracheal cells, these compounds induce differentiation of mouse embryonal carcinoma F9 and human promyelocytic leukemia HL60 cells. The Am- and Ch- series of compounds also affect several parameters of cell proliferation. These agents are very potent inhibitors of growth of melanoma S91 cells and inhibit the induction of ornithine decarboxylase activity by phorbol 12-myristate 13-acetate in 3T6 fibroblasts. These results show that the Am- and Ch- derivatives elicit in several cell systems the same cellular responses as retinoic acid. We propose, therefore, that they exhibit mechanism(s) of action similar to those of retinoids. Comparison of the biological response with the binding capacity to the cellular retinoic acid-binding protein shows a lack of a direct correlation.

Animals↗
PubMed1986

Mechanism of action of retinoids.

In several recent reviews, we have suggested that the mechanism of action of retinoids in controlling cell differentiation is related to their effects on the expression of oncogenes and peptide growth factors. It is currently believed that oncogenes control metabolic pathways that involve peptide growth factors and their receptors, as well as postreceptor signaling mechanisms. Retinoids, therefore, have been valuable probes to study the function of oncogenes and peptide growth factors. In several tumor cells, including human promyelocytic leukemia, human and murine neuroblastoma, and murine teratocarcinoma, retinoic acid induces terminal differentiation, accompanied by suppression of the expression of either the c-myc or the N-myc gene. Many studies have indicated that retinoic acid can markedly increase the number of cellular receptors for epidermal growth factor, which is partially encoded by another oncogene, erb-B. We have shown that retinoic acid greatly inhibits the anchorage-independent growth of a rat fibroblast cell line that has been transfected with the c-myc gene, particularly when these cells are stimulated by the combination of platelet-derived growth factor and transforming growth factor-beta. At present, the mechanisms by which retinoids control oncogene and growth factor expression are unknown. A wide range of new compounds, including the retinoidal benzoic acid derivatives, are now available to study these mechanisms, and will necessitate the identification of a high-affinity receptor for retinoids and the elucidation of the interaction of this receptor with the genome of the cell. The recent synthesis of new terephthalic acid anilides and chalcone carboxylic acid derivatives, which have retinoid-like activity, offers a particularly useful approach to this problem.

Animals↗