In vitro and in vivo evaluation of a standardized Curcuma longa Linn formulation in cervical cancer.

BACKGROUND: The anti-cancer activity of phytomolecules present in turmeric or haridra (Curcuma longa Linn) extracts against cancer has been described in various 'in vitro and in vivo' studies. OBJECTIVE: In the present study, in vitro and in vivo anti-cancer and chemo-preventive activity of a new standardized Supercritical Turmeric Oil Extract (SCTOE) NBFR-03 was evaluated in cervical cancer models. METHODS AND MATERIALS: In vitro cytotoxicity of this formulation was assessed at 10, 20, 40, and 80 µg/ml concentrations, in three cervical cancer cell lines (HeLa, SiHa, ME180) using Sulforhodamine B assay. The in vivo anti-cancer activity was evaluated in two groups of female nude mice; the first one was with tumor xenograft implants and at the same time treatment was started with 96 µl/kg/day p.o. and 192 µl/kg/day p.o. NBFR-03 for three months. The second group was kept as chemoprevention group where mice were pre-treated with the formulation (96 µl/kg/day p.o.) for two weeks and injected with cancer cell suspension with continued treatment for three months. RESULTS: No cytotoxicity was seen in any cell line with the extract when compared to positive control (Adriamycin 10 µg/ml). In mice the first treatment group with tumor xenograft implants did not show any significant anti-tumor activity but showed a trend where higher dose group had smaller tumor volumes as compared to lower dose group and controls (p = 0.37 and p = 0.34 respectively). The chemopreventive group with pre-treated mice also showed smaller tumor size as compared to controls (p = 0.163). CONCLUSION: NBFR-03 turmeric oil extract showed a promising trend in mice pre-treated with NBFR-03. There is a scope for further studying the potential of this extract as complementary therapy and as a chemopreventive.

Mutagenicity of gingerol and shogaol and antimutagenicity of zingerone in Salmonella/microsome assay.

Ginger extract and its constituents gingerol, shogaol and zingerone were tested in Salmonella typhimurium strains TA 100, TA 98, TA 1535 and TA 1538 in the presence and in absence of S9 mix. It was observed that ginger extract, gingerol and shogaol were mutagenic on metabolic activation in strains TA 100 and TA 1535, but zingerone was non-mutagenic in all the four strains with or without S9 mix. When mutagenicity of gingerol and shogaol was tested in presence of different concentrations of zingerone it was observed that zingerone suppressed mutagenic activity in both the compounds in a dose dependent manner.

Mutagenic and cytogenetic studies of N'-nitrosonornicotine and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone.

The tobacco specific nitrosamines (TSNA) N'-nitrosonornicotine (NNN) and 4-(Methylnitrosoamino)-1-(3-pyridyl)-1-butanone (NNK) were tested for mutagenic and clastogenic effects using a battery of short-term test systems. These test systems include the Ames test, micronucleus test (MNT), induction of chromosomal aberrations and sister chromatid exchange (SCEs). NNN and NNK were tested for their potency in inducing mutations in the Ames Salmonella/microsome assay and their clastogenic action were tested by the micronucleus inducing ability in vivo using Swiss mice. Studies on the induction of chromosomal aberrations and SCE exchange were carried out using human peripheral blood lymphocyte cultures. In the Ames test and MNT, NNN was positive but in comparisons with NNK, NNK was a more potent mutagen. Present studies clearly proves the genotoxic potential of both NNN and NNK and between the two NNK is more potent.

Effect of tobacco extract and N'-nitrosonornicotine on the carcinogen metabolising enzymes under different dietary vitamin B status.

Studies were carried out to evaluate the changes in the phase I and II enzymes of xenobiotic metabolism, on treatment with tobacco extract (TE) and a tobacco specific carcinogen, N'-nitrosonornicotine (NNN) in Sprague-Dawley rats maintained on vitamin B complex sufficient and deficient semi-synthetic diets. Both TE and NNN significantly increased the hepatic and pulmonary phase I enzymes in the vitamin B sufficient (SB+) and deficient (SB-) animals. However, the percent increase in enzyme activities was drastically higher in the SB- treated group as compared to those in the SB(+)-treated group. On the other hand, TE and NNN significantly depressed the liver and lung glutathione (GSH) level and glutathione S-transferase (GST) activity in the SB- animals, while the opposite effect was observed in the SB(+)-treated animals. Furthermore, both the treatments depleted the hepatic pool of vitamin A, with a concurrent increase in that of vitamin C in SB+ and SB- groups.

Anticarcinogenic effect of betel leaf extract against tobacco carcinogens.

Epidemiological studies have implicated that betel quid offers some protection to tobacco induced carcinogenesis. Earlier studies in our laboratory have shown betel leaf extract (BLE) to be antimutagenic against standard mutagens and tobacco-specific N'-nitrosamines (TSNA), N'-nitrosonornicotine (NNN) and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK). In the present study, we have tested the anticarcinogenic effect of BLE using Swiss male mice. Two protocols of study were used to test this effect. In the first protocol, the effect of BLE was tested against the standard carcinogen benzo[a]pyrene (BP) using Wattenberg's stomach tumor model, Cancer Res., 41 (1981) 2820-2823. In this protocol, BLE inhibited the tumorigenicity of BP to a significant extent. In the second protocol, the effect of BLE against the two tobacco-specific nitrosamines, NNN and NNK was studied using long-term studies on Swiss male mice. The nitrosamines were administered on the tongues of the mice, while the BLE was supplied in drinking water. Two doses of NNN (22 mg and 72 mg) and one dose of NNK (22 mg) were used. In this study, it was observed that the number of tumor bearing animals decreased, but the difference was significant only in the group treated with the low dose of NNN in combination with BLE. However, in all the BLE treated animals, irrespective of the dose of nitrosamine, the hepatic vitamin A and C levels were elevated significantly as compared to the corresponding nitrosamine-treated controls. These results indicate that BLE has a promising anticarcinogenic role to play in tobacco induced cancer.(ABSTRACT TRUNCATED AT 250 WORDS)

Studies on high-dose chemotherapy of amygdalin in murine P388 lymphocytic leukaemia and P815 mast cell leukaemia.

The anti-tumor activity of amygdalin (NSC 251222), commercially known as Laetrile, was investigated using P388 lymphocytic leukaemia and P815 mast-cell leukaemia in BDF1 mice. Doses varying from 200 mg/kg to 2,000 mg/kg were used following the days 1 and 5 and days 1, 5 and 9 schedules. Despite treatment with high doses of amygdalin there was no prolongation in the life-span of mice bearing either P388 or P815 tumor.

Catechin as an antimutagen: its mode of action.

In the present study, we report that the betel quid ingredient catechu, its extract and pure principle catechin were nonmutagenic in Salmonella typhimurium TA 100, TA 1535, TA 98, and TA 1538 assays with or without metabolic activation. They also exhibited dose-dependent decreases in mutagenicity of benzo(a)pyrene [B(a)P] and dimethylbenz(a)anthracene (DMBA) in strain TA 98 with metabolic activation. We further report that these compounds inhibited activities of cytochrome P-450 and had no effect on glutathione-S-transferase but increased the glutathione content in rat liver tissue. Simultaneous treatment of catechin prevented the mutagenic activity of B(a)P and DMBA metabolites in strain TA 98 in the absence of metabolic activation. Pre- and post-treatment of bacteria with catechin had no effect on the mutagenicity of B(a)P and DMBA metabolites. Catechin also inhibited the in vitro binding of 3H-B(a)P metabolites to calf thymus DNA. Catechu extract and catechin inhibited the nitrosation of methylurea by nitrite at pH 3.6 and 30 degrees C. The formation of nitrosomethylurea in the reaction mixture was monitored by measuring the histidine revertants of strain TA 1535 in the absence of metabolic activation. Pre- and post-treatment of catechu extract or catechin had no effect on the mutagenicity of nitrosomethylurea in TA 1535. The nitrosation inhibition by catechin was through scavenging of nitrite observed at pH 3.6. The above study indicates that catechu in betel quid may act as an antimutagen and may suppress the mutagenic potential of other betel quid mutagens.

Some mixed-ligand palladium(II) complexes of 2,2'-bipyridine and amino acids as potential anticancer agents.

Eight new palladium complexes of the formula [Pd(bipy)(AA)]Cl 1 or 2 H2O (where bipy is 2,2'-bipyridine and AA is an anion of glycine, L-alanine, L-leucine, L-proline, L-serine, L-lysine, L-asparagine, or L-glutamine) have been synthesized by reaction of [Pd(bipy)Cl2] with an appropriate mono sodium salt of amino acid in water. These complexes have been characterized by chemical analysis and by visible, infrared, and 1H NMR spectroscopy. The detailed 1H NMR and infrared spectral studies of these complexes ascertain the mode of binding of amino acids to palladium through nitrogen of terminal -NH2 group and oxygen of terminal -COO- group. The molar conductance values of these complexes in water suggest them to be 1:1 electrolytes. These complexes have also shown growth inhibition against L1210 lymphoid leukemic, P388 lymphocytic leukemic, Sarcoma 180, and Ehrlich ascitic tumor cells. Some of these complexes show better 50% inhibitory dose values than cis-diamminedichloroplatinum(II).

Some potential anticancer palladium(II) complexes of 2,2'-bipyridine and amino acids.

Nine new palladium(II) complexes of the formula [Pd(bipy)(AA)]n+ (where bipy is 2,2'-bipyridine, AA is an anion of L-cysteine, L-aspartic acid, L-glutamic acid, L-methionine, L-histidine, L-arginine, L-phenylalanine, L-tyrosine, or L-tryptophan, and n = 0 or 1) have been synthesized by interaction of [Pd(bipy)Cl2] with an appropriate sodium salt of amino acid in water. These palladium(II) complexes have been characterized by chemical analysis and by visible, infrared, and 1H NMR spectroscopy. The modes of binding of amino acids in these palladium complexes have been ascertained by infrared and 1H NMR spectroscopy. The molar conductances of these complexes in water suggest that they are either nonelectrolytes or 1:1 electrolytes. These palladium complexes have shown growth inhibition against L1210 lymphoid leukemic, P388 lymphocytic leukemic, Sarcama 180, and Ehrlich ascites tumor cells. Some of these complexes show I.D.50 values comparable to or lower than cis-diamminedichloroplatinum(II).

Synthesis and spectroscopic studies of potential anticancer [platinum(II)(2,2'-bipyridine)(amino acid)]n+ (n = 1 or 2) complexes.

Six new platinum complexes of the formula [Pt(2,2'-bipyridine)(amino acid)]n+, where n = 1 to 2 and amino acid is an anion of L-histidine, L-lysine, L-asparagine, L-phenylalanine, L-tryptophan, or L-tyrosine, have been prepared by interaction of [Pt(2,2'-bipyridine)Cl2] and an appropriate amino acid (sodium salt) in water or water-methanol mixture. They have been characterized by chemical analyses and spectral methods such as ultraviolet-visible, infrared, and 1H NMR spectroscopy. The 1H NMR studies of these complexes ascertain the modes of binding of amino acids to platinum. The histidine binds to platinum through the nitrogen of a -NH2 group and another nitrogen of heterocyclic ring. All other amino acids bind to platinum through nitrogen of a -NH2 group and oxygen of a -COO- group. The mode of binding of some amino acids to platinum in these complexes has been further confirmed by infrared spectroscopy, and the formulations of these complexes have been supported by conductivity measurements. These six amino acid complexes and also other complexes of glycine, alanine, leucine, serine, cysteine, methionine, and glutamine have shown growth inhibition against P-388 lymphocytic leukemic cells.

Protective effect of hydroxychavicol, a phenolic component of betel leaf, against the tobacco-specific carcinogens.

The phenolic compound, hydroxychavicol (HC), present in betel leaf, was synthesised and tested for its antimutagenic effect against the mutagenicity of the 2 tobacco-specific N-nitrosamines (TSNA), N'-nitrosonornicotine (NNN) and 4-(nitrosomethylamino)-1-(3-pyridyl)-1-butanone (NNK), in 2 different test systems, viz. the Ames Salmonella/microsome assay and the micronucleus test using Swiss male mice. We are reporting the synthesis of HC of a high degree of purity. We observed that HC suppressed the mutagenic effects of NNN and NNK in both test systems used. These results indicate that HC may have a role to play in reducing the risk of oral cancer in betel quid with tobacco chewers.

Curcumins as inhibitors of nitrosation in vitro.

The effects of turmeric extract and its pure yellow pigments curcumin I, II and III were tested on the nitrosation of methylurea by sodium nitrite at pH 3.6 and 30 degrees C. The nitrosomethylurea formed was monitored by checking the mutagenicity in S. typhimurium strains TA1535 and TA100 without metabolic activation. Turmeric extract as well as curcumins exhibit dose-dependent decreases of nitrosation. Curcumin III was the most effective nitrosation inhibitor among the compounds tested. The simultaneous treatment of inhibitor with nitrosation precursors was essential and pre- or post-treatment of inhibitor had no effect on the mutagenicity of nitrosomethylurea. The binding of nitrite with the inhibitors was studied at pH 3.6 and 30 degrees C. Curcumin I shows a dose-dependent depletion of nitrite ions thus making nitrite non-available for nitrosation. Curcumin I and III when tested also showed a time-dependent depletion of nitrite ions at pH 3.6 and 30 degrees C. Curcumin III has a higher affinity for nitrite ions than curcumin I.

Chemosensitivity of advanced larynx carcinoma cells in vitro and significance of multidrug resistance markers in these tumors.

Thirty cases of previously untreated advanced larynx carcinoma were checked for in vitro chemosensitivity and presence of the resistance markers viz. P-glycoprotein (P-gp) glutathione-S-transferase-pi (GST-pi) and protein kinase C (PKC) overexpression. The cytotoxicity testing was done using MTT assay and the resistance markers were checked by immunohistochemical methods using monoclonal antibodies. The drug combinations employed in MIT assay were 5FU* + MTX*, 5FU + cisPt*, 5FU + Mito*, cisPt + Mito and MTX + Mito (*5FU = 5Fluorouracil, MTX-methotrexate, cisPt-cisplatin and Mito = mitomycin C). No statistically significant correlation was observed between resistance to the above drug combinations and presence of the resistance markers under consideration. A statistically significant correlation was observed between node positivity and expression of resistance markers which indicates that presence of one or more of these markers in these tumors may be considered as a negative prognosis marker. CisPt-Mito was found to be the most effective drug combination in vitro, in the cases studied.

In vitro antimutagenicity of curcumin against environmental mutagens.

The effects of curcumin, the yellow pigment of the spice, turmeric (Curcuma longa) on the mutagenicity of several environmental mutagens were investigated in the Salmonella/microsome test with or without Aroclor 1254-induced rat-liver homogenate (S-9 mix). With Salmonella typhimurium strain TA98 in the presence of S-9 mix, curcumin inhibited the mutagenicity of bidi and cigarette smoke condensates, tobacco and masheri extracts, benzo[a]pyrne and dimethyl benzo[a]anthracene in a dose-dependent manner. Curcumin did not influence the mutagenicity without S-9 mix of sodium azide, monoacetylhydrazine and streptozocin in strain TA100 nor of 4-nitrophenylenediamine in strain TA98. Our observations indicate that curcumin may alter the metabolic activation and detoxification of mutagens.

Hydroxychavicol: a new phenolic antimutagen from betel leaf.

The phenolic compounds eugenol and hydroxychavicol were separated from betel leaf extract using C18 phase bonded Hiflosil silica gel. The structures of the two compounds were confirmed by nuclear magnetic resonance data. Neither eugenol nor hydroxychavicol was mutagenic when tested in various strains of Salmonella typhimurium with or without metabolic activation. Both compounds exhibited dose-dependent suppression of dimethylbenzanthracene-induced mutagenesis in S. typhimurium strain TA98 with metabolic activation. Hydroxychavicol was more potent than eugenol in this respect.

Nonmutagenicity of betel leaf and its antimutagenic action against environmental mutagens.

Betel leaf (Piper betel) water and acetone extract are nonmutagenic in S. typhimurium strains with and without S9 mix. Both the extracts suppress the mutagenicity of betel quid mutagens in a dose dependent manner. Moreover both the extracts of betel leaf reduce the mutagenicity of benzo(a)pyrene and dimethylbenzanthracene. Acetone extract is more potent than water extract in inhibiting mutagenicity of environmental mutagens.

Chemopreventive efficacy of a betel leaf extract against benzo[a]pyrene-induced forestomach tumors in mice.

The effect of betel leaf extract and some of its constituents, eugenol, hydroxychavicol, beta-carotene and alpha-tocopherol, on benzo[a]pyrene-induced forestomach neoplasia in male Swiss mice was examined. Betel leaf and its constituents decreased the number of papillomas per animal with the maximum protection, considering molar dosage, exhibited by beta-carotene and alpha-tocopherol. Except for beta-carotene, eugenol, hydroxychavicol and alpha-tocopherol increased the levels of reduced glutathione in the liver while glutathione S-transferase activity was enhanced by all except eugenol. Of seven sources, Banarasi betel leaves showed the maximum amounts of beta-carotene and alpha-tocopherol.

Antitumor effect of L-alanosine (NSC 153553) on sensitive and resistant sublines of murine leukemias.

The antitumor action of L-alanosine (NSC 153553) was investigated in murine leukemia P388 (P388/S), P388 resistant to adriamycin (P388/ADR), P388 resistant to vincristine (P388/VCR) and leukemia L5178Y sensitive to L-asparaginase (L5178Y/S). L-alanosine demonstrated good antineoplastic activity against P388/S and P388/ADR, whereas it showed better anticancer activity against P388/VCR and L5178Y/S at the various dose levels employed.

Chemopreventive efficacy of betel leaf extract and its constituents on 7,12-dimethylbenz(a)anthracene induced carcinogenesis and their effect on drug detoxification system in mouse skin.

Effects of topically applied betel leaf extract (BLE) and its constituents. beta-carotene, alpha-tocopherol, eugenol and hydroxychavicol on 7,12-dimethylbenz(a)anthracene (DMBA) induced skin tumors were evaluated in two strains of mice. BLE, beta-carotene and alpha-tocopherol, significantly inhibited the tumor formation by 83, 86, 86% in Swiss mice and 92, 94 and 89% in male Swiss bare mice respectively. Hydroxychavicol showed 90% inhibition in Swiss bare mice at 24 weeks of treatment. Eugenol showed minimal protection in both strains of mice. The mean latency period and survivors in BLE, beta-carotene, alpha-tocopherol and hydroxychavicol treated groups were remarkably high as compared to DMBA alone treated group. Intraperitoneal injection of betal leaf constituents showed a significant effect on both glutathione and glutathione S-transferase levels in the Swiss mouse skin.

Effect of nutritional status on mutagenicity of urine excreted by rats treated with standard/experimental carcinogens.

Urine samples, collected from Sprague Dawley rats treated with extracts of tobacco/masheri, benzo (a) pyrene, N'-nitrosonornicotine, N'-nitrosodiethylamine and maintained on semi-synthetic diets sufficient or deficient in Vitamin A, B and protein were tested for mutagenicity using Salmonella/microsome assay. The mutagenic activity of urine or various treated groups was in the order deficient diet greater than standard laboratory diet greater than nutritionally sufficient diet. Present results confirmed the earlier observations that nutritionally deficient animals are likely to have more exposure to mutagenic metabolites that are generated by increased phase I enzymes and decreased detoxification system.