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R K Zee-Cheng

Publications and source records attributed to R K Zee-Cheng.

At least 19 recordsLinked to original sources
PubMed1992

Shi-quan-da-bu-tang (ten significant tonic decoction), SQT. A potent Chinese biological response modifier in cancer immunotherapy, potentiation and detoxification of anticancer drugs.

Shi-Quan-Da-Bu-Tang (Ten Significant Tonic Decoction), or SQT (Juzentaihoto, TJ-48) was formulated by Taiping Hui-Min Ju (Public Welfare Pharmacy Bureau) in Chinese Song Dynasty in AD 1200. It is prepared by extracting a mixture of ten medical herbs (Rehmannia glutinosa, Paeonia lactiflora, Liqusticum wallichii, Angelica sinesis, Glycyrrhiza uralensis, Poria cocos, Atractylodes macrocephala, Panax ginseng. Astragalus membranaceus and Cinnamomum cassia) that tone the blood and vital energy, and strengthen health and immunity. This potent and popular prescription has traditionally been used against anemia, anorexia, extreme exhaustion, fatigue, kidney and spleen insufficiency and general weakness, particularly after illness. In order to restore immunity in cancer patients, potentiate the therapeutic effect and ameliorate adverse toxicity of anticancer agents, 116 Chinese herbal formularies (Kampo) have been screened and evaluated. Fifteen compounds were found to have such actions. Among these, SQT was selected as the most effective as a potent biological response modifier. During the last eight years, animal models and clinical studies have revealed that SQT demonstrates extremely low toxicity (LD50 > 15 g/kg op murine), self-regulatory and synergistic actions of its components in immunomodulatory and immunopotentiating effects (by stimulating hemopoietic factors and interleukins production in association with NK cells, etc.), potentiates therapeutic activity in chemotherapy (mitomycin, cisplatin, cyclophosphamide and fluorouracil) and radiotherapy, inhibits the recurrence of malignancies, prolongs survival, as well as ameliorate and/or prevents adverse toxicities (GI disturbances such as anorexia, nausea, vomiting, hematotoxicity, immunosuppression, leukopenia, thrombocytopenia, anemia and nephropathy, etc.) of many anticancer drugs. The application and mechanistic studies of SQT in future development have potential importance in basic and clinical research of the traditional Chinese therapeutic approach of "toning the blood and strengthening Qi (vital energy)" in cancer immunotherapy.

Animals↗
PubMed1988

Screening and evaluation of anticancer agents.

The screening and evaluation procedures for the development of anticancer agents indicated that the entire process is a rather difficult task. This is particularly true in choosing screening models and criteria for activity. If the criteria were set too low, then some clinically false-positive results may be faced; and if the criteria were set too high, some agents could be missed which might be effective against certain types of human cancer. Presently, active compounds are selected by prescreening and screening against transplanted mouse tumors and human tumor xenografts as well as by the in vitro systems. Xenografts of human tumor in athymic nude animals represent metabolic characteristics of human malignant disease which appear to be of value in the preclinical screening. Human tumor cloning assays have gained increased attention as a promising in vitro test system for the screening as well as for the prediction of patient responses. Application of chemosensitivity tests in the prediction of the responses of individuals to chemotherapy, especially in the identification of drug resistant tumors are, in general, quite reliable. Human tumor xenografts, human tumor cloning assays and chemosensitivity tests may be regarded as the major impetus in screening during the past decade. After promising agents are selected from the screening procedures, before the filing of an investigational new drug application, the preclinical toxicology and pharmacology should be completed. Information on the nature of toxicity, dose-response effects, and dose schedule are necessary for predicting the effects of the drug in man. The new drugs then go through three phases of clinical trials to assure safety, effectiveness, and reliability of the drugs. During the past fifteen years eight-three antineoplastic drugs were evaluated clinically under the NCI sponsorship and twenty-four are active in at least one disease. Among these active drugs, eleven possess novel clinical structure, the remaining thirteen are analogues of known active compounds already in clinical trials. After an investigational anticancer drug is approved by the U.S. Food and Drug Administration it becomes a commercial product on the market and the benefits can be shared by the general public. The time required for evaluation and development from the first discovery of activity to final FDA approval for fifty-two therapeutic drugs are tabled. The average interval is 8.8 years, but in the 1950s the average was only 2.8 years, in the 1960s, 6.5 years; in the 1970s, 13.9 years; and in the 1980s, 16.0 years. This reflects the increasing stricter requirements for an antineoplastic drug to be officially recognize

Animals↗
PubMed1987

Structural modification study of mitoxantrone (DHAQ). Chloro-substituted mono- and bis[(aminoalkyl)amino]anthraquinones.

A number of chloro-substituted [(aminoalkyl)amino]anthraquinones were synthesized and evaluated for their antineoplastic and cytotoxic activity. Treatment of 5,8-dichloroquinizarin with substituted amines in pyridine resulted in the replacement of one halogen atom by the amino group to yield mainly 1-chloro-5,8-dihydroxy-4-(substituted amino)anthraquinones. On the other hand, reaction between the dichloroquinizarin and the amines in butanol gave predominantly 1,4-dichloro-5-hydroxy-8-(substituted amino)anthraquinones. Other compounds in this series were prepared by displacement of chloro, nitro, or tosyl functions of the appropriate anthraquinone derivatives with various amines by conventional methods. 1,4-Dichloro-5-hydroxy-8-[[2-[(2-hydroxyethyl)amino]ethyl]amino] anthraquinone (6b) possesses the highest inhibitory activity against P388 leukemia. Its inhibitory action against B16 melanoma and against the in vitro L1210 screen is also significant. Several other chloro- and hydroxy-substituted aminoanthraquinones (5a, 5b, and 6a) also showed noticeable activity against P388 in vivo and L1210 in vitro. Structure-activity-relationship examination indicated that the hydroxyl group may contribute to the binding of certain chloroaminoanthraquinones for their biological activity and that the [2-[(2-hydroxyethyl)amino]ethyl]amino side chain seems to be the preferred substituent over other amino side chains.

Animals↗
PubMed1986

Amino-substituted p-benzoquinones.

Based on the observation of outstanding antineoplastic activity of a number of amino-substituted anthraquinones, thioxanthones, and N-(aminoethyl)-substituted naphthalimides, four types of amino-substituted p-benzoquinones were designed, synthesized, and their biological activity evaluated. Although none of these compounds exhibited inhibitory activity against P388 leukemia, 2,5-bis[[4-[(dimethylamino)methyl]phenyl]amino]-3,6-dibromo-1,4- benzoquinone and the corresponding dichloro compound demonstrated good inhibitory activity against the proliferating human colon adenocarcinoma in vitro. The dichloro compound was also found to be active against the leukemia L1210 screening in vitro. 2,5-Bis[[2-(dimethylamino)ethyl]amino]-1,4-benzoquinone possessed inhibitory activity against Neisseria catarrhali.

Adenocarcinoma↗
PubMed1985

N-(Aminoalkyl)imide antineoplastic agents. Synthesis and biological activity.

The similarity of the side-chain characteristics of 1,4-dihydroxy-5,8-bis[[2-[(2-hydroxyethyl)amino]ethyl]amino]- anthraquinone (DHAQ), discovered by us in 1978, and those of the N-substituted imides of 3-nitro-1,8-naphthalic acid, discovered by other investigators recently, led us to conduct a systematic study on the N-(aminoalkyl)-substituted derivatives of a variety of imides. Areas of study included (a) selection of the ring system, (b) modification of the side chain, (c) substitution on certain chosen ring systems, and (d) combinations of the aforementioned variants. Preliminary biological activity screening indicated that N-(dialkylaminoethyl)imides of the 3,6-dinitro- and 3,6-diamino-1,8-naphthalic acid system possessed prominent antileukemia and antimelanoma activity in both in vitro and in vivo experimental tumor systems.

Adenocarcinoma↗
PubMed1982

Structure-activity relationship study of anthraquinones: 1,4-dihydroxy-5,8-bis[[2-(2-hydroxyethoxy)ethyl]amino]-9,10-anthracenedione, an analog of an established antineoplastic agent.

An oxygen analog of the antineoplastic anthraquinone, 1,4-dihydroxy-5,8-bis[[2-(2-hydroxyethyl)amino]ethyl]amino - 9,10-anthracenedione, was synthesized. This compound, 1,4-dihydroxy-5,8-bis[[2-(2-hydroxyethoxy)ethyl]amino] - 9,10-anthracenedione, was found to be inactive against P-388 lymphocytic leukemia. A comparative structure-activity study of these two anthraquinones in terms of previously postulated N--O--O triangulation hypothesis was discussed.

Animals↗
PubMed1979

Antileukemic activity of substituted ureidothiazoles, ureidothiadiazoles, and related compounds.

A number of ureidothiazole and ureidothiadiazole derivatives related to ethyl 4-[[(2-thiazolylamino)carbonyl]-amino]benzoate were prepared and evaluated against the leukemia P-388 tumor system in mice. Preliminary structure-activity relationship study revealed that, among other considerations, active compounds of this series contain either an "isothioureido" [N-C(S-)=N-] or an "isothiosemicarbazono" [N-C(S-)=N-N=] structural unit.

Animals↗
PubMed1979

Structural modification study of bis(substituted aminoalkylamino)anthraquinones. An evaluation of the relationship of the [2-[(2-hydroxyethyl)amino]ethyl]amino side chain with antineoplastic activity.

Several anthraquinones containing the [2-[(2-hydroxyethyl)amino]ethyl]amino, the [2-(dimethylamino)ethyl]amino, and the 2-(dimethylamino)ethoxy groups were prepared. Preparation of a lucanthone analogue, a 7-chloroquinoline derivative, and derivatives of naphthoquinones containing the [2-[(2-hydroxyethyl)amino]ethyl]amino side chain and related amino-substituted side chains was also conducted. It was found that the antineoplastic activity of anthraquinones containing the [2-[(2-hydroxyethyl)amino]ethyl]amino side chain is superior to those containing the tertiary amino side chain. However, the presence of the [2-[(2-hydroxyethyl)amino]ethyl]amino chain is an important, but not a sufficient, factor for good antineoplastic activity, as indicated by the lack of significant biological activity of other ring systems containing this side chain.

Animals↗
PubMed1979

Experimental antitumor activity of aminoanthraquinones.

The activity of a number of substituted alkylaminoanthraquinones was compared in transplanted murine tumor systems including P388 and L1210 leukemias, B16 melanoma, and colon carcinoma 26. The structure-activity relationships among this class of compounds are discussed. Several derivatives had very high antitumor activity in several tumor systems. Two of the most active derivatives, namely, 1,4-bis(2-[(2-hydroxyethyl)amino]ethylamino)-9,10-anthracenedione (bisalkylAAD) and 1,4-dihydroxy-5,8-bis(2-[(2-hydroxyethyl)amino]ethylamino)-9,10-anthracenedione (dihydroxybisalkylAAD), which had curative activity in the above-mentioned tumors, were compared in considerable detail. DihydroxybisalkylAAD showed distinct advantages over bisalkylAAD in several tumor systems and is tenfold more potent with respect to effective dose range. This last difference is important for two reasons. First, these aminoanthraquinones are strong and persistent blue dyes and the administration of lower doses would minimize a potential cosmetic drawback of these compounds. Second and most important, iv administration of dose levels of bisalkylAAD which are within the therapeutic dose range on intermittent dose schedules produced convulsions and immediate death. IV administration of dihydroxybisalkylAAD also caused acute toxicity, but, because of its increased potency relative to antitumor activity and delayed toxicity, this acute toxicity was apparent only at doses well above the therapeutic dose range. All of the aminoanthraquinones evaluated, regardless of their activity as antitumor agents in vivo, proved to be potent inhibitors of DNA and RNA synthesis in vitro and bound strongly to DNA as evidenced by deltaTm values (deltaTm = upward shift in DNA melting temperature). Thus, the strong antitumor activity of aminoanthraquinones would appear to be due to some mechanism other than, or in addition to, DNA binding and inhibition of nucleic acid synthesis.

Animals↗
PubMed1978

Antileukemic activity of ungeremine and related compounds. Preparation of analogues of ungeremine by a practical photochemical reaction.

A number of alkoxypyrrolophenanthridinium salts and their analogues related to the antileukemic alkaloid ungeremine were prepared by a practical photochemical cyclization. The importance of the quaternary nitrogen atom and of alkoxy groups, the planarity of a molecule, and steric considerations relative to antileukemic activity are discussed.

Alkaloids↗
PubMed1978

Antineoplastic agents. Structure-activity relationship study of bis(substituted aminoalkylamino)anthraquinones.

A structure-activity relationship study was conducted on a number of bis(substituted aminoalkylamino)anthraquinones. These compounds were prepared by the condensation of substituted or unsubstituted leucoquinizarin with appropriate amines, followed by air oxidation. Both the position and the nature of the center nitrogen atom of the side chain are vital to the antineoplastic activity. The possible mode of action of these aminoquinones was discussed. 1,4-Dihydroxy-5,8-bis[[2-(hydroxyethyl)amino]ethyl]amino-9,10-anthracenedione (DHAQ) was found to possess potent inhibitory activity against both the P-388 leukemia system (T/C of 299 at 0.5 mg/kg with 4/6 cures) and the B-16 melanoma system (T/C of 503 at 1 mg/kg with 7/10 cures).

Animals↗
PubMed1977

Inhibition of catechol O-methyltransferase and transfer RNA methyltransferases by coralyne, nitidine, and related compounds.

Inhibitory activity against both catechol O-methyltransferase and transfer RNA methyltransferases was observed among the antileukemic alkaloids coralyne, nitidine, and related synthetic alkoxy analogs. Inhibition of both classes of enzymes seems to have a similar profile. The role of water solubility of these compounds with regard to their enzyme inhibitory activity was noted.

Animals↗
PubMed1977

Absence of mutagenicity of coralyne and related antileukemic agents: structural comparison with the potent carcinogen 7,12-dimethylbenz[a]anthracene.

The structural similarity between antileukemic alkaloid coralyne and the carcinogenic and antineoplastic hydrocarbon 7, 12-dimethylbenz[a]anthracene, as well as the similarity between the antileukemic alkaloid nitidine and the carcinogenic hydrocarbon 5-methylchrysene, prompted a mutagenicity evaluation of coralyne sulfoacetate, nitidine chloride, the 8-ethyl homolog of coralyne, nitidine methosulfate, and the tetramethoxy analog of nitidine by the Ames method against the histidine-auxotroph strains of Salmonella typhimurium TA-1537, TA-1538, TA-98, and TA-100; 7,12-dimethylbenz[a]anthracene was used as a reference standard. The mutagenicity of these antileukemic compounds was either completely eliminated or drastically reduced, but the mutagenic response was generally high for 7,12-dimethylbenz[a]anthracene. The results suggest that the presence of a quaternary nitrogen atom and alkoxy groups could be important in alleviating the mutagenicity of the parent mutagenic and carcinogenic hydrocarbons.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1976

Some substituted naphthazarins as potential anticancer agents.

Some 2,3-bis(substituted methyl)naphthazarins and related compounds were synthesized by the Diels-Alder reaction of benzoquinone and 2,3-dimethylbutadiene followed by oxidation and substitution reactions. These compounds were prepared as potential biological alkylating agents. Screening results indicated that 1,4-diacetyl-6,7-dimethyl-4a,5,8,8a-tetrahydronaphthalene and 5,8-bis(benzoyloxy)-2,3-dimethyl-1,4-naphthoquinone possessed borderline activity against leukemia P388 and that naphthazarin diacetate possessed confirmed cytotoxicity against the cell culture of human epidermoid carcinoma of the nasopharynx.

Animals↗