New cytotoxic isoprenoid derivatives from the Red Sea soft coral Sarcophyton glaucum

Chemical investigation of the soft coral Sarcophyton glaucum collected from the Red Sea led to isolation of 11 isoprenoidal metabolites (1-11). A new sesquiterpenoid, 6-oxo-germacra-4(15),8,11-triene (1), a new natural cembranoid, sarcophinediol, along with two known sesquiterpenoids (2 and 3) and seven known cembranoids (5-11) was obtained. The structures of the compounds were established based on their NMR, MS, IR and UV spectral data. All compounds were evaluated for their cytotoxicity employing three cancer cell lines (HepG2, MCF-7 and HCT116). Compounds 4 and 6 showed significant cytotoxicity towards HepG2 with IC50 values of 18.8 ± 0.07 and 19.9 ± 0.02 μM; respectively. Compounds 5-7 exhibited potent cytotoxicity against MCF-7 cells with IC50 values of 9.9 ± 0.03, 2.4 ± 0.04 and 3.2 ± 0.02 μM, respectively. Compounds 1, 4 and 5 showed significant activities towards HCT116 cells with IC50 values of 29.4 ± 0.03, 19.4 ± 0.02 and 25.8 ± 0.03 μM, respectively.

Acute cyanide Intoxication: A rare case of survival

A 30-year-old male jewellery factory worker accidentally ingested silver potassium cyanide and was brought to the emergency department in a state of shock and profound metabolic acidosis. This patient was managed hypothetically with use of injection thiopentone sodium intravenously until the antidote was received. Cyanide is a highly cytotoxic poison and it rapidly reacts with the trivalent iron of cytochrome oxidase thus paralysing the aerobic respiration. The result is severe lactic acidosis, profound shock, and its fatal outcome. The patient dies of cardio-respiratory arrest secondary to dysfunction of the medullary centres. It is rapidly absorbed, symptoms begin few seconds after exposure and death usually occurs in <30 min. The average lethal dose for potassium cyanide is about 250 mg. We used repeated doses of thiopentone sodium till the antidote kit was finally in our hands, hypothesising that it contains thiol group similar to the antidote thiosulphate. Moreover, it is an anticonvulsant. We were successful in our attempts and the patient survived though the specific antidotes could be administered after about an hour.

Evaluation of the toxic activity of anorectic diethylpropion in Chinese hamster ovary cells

Diethylpropion has been available in the market for treating obesity for over 50 years. Refined studies are lacking to fully elucidate its action spectrum. The aim of our study was to evaluate possible toxic effects of anorectic diethylpropion in Chinese hamster ovary (CHO) cells. Comet assay (detects breaks in the DNA strand), micronucleus test (detects clastogenic/aneugenic damage), and cell survival test (detects cytotoxic damage) were used to evaluate the toxic effects. In comet assay, we found that the damage scores with diethylpropion treatments at the concentrations of 20 and 40 μg/mL were more significant ( p < 0.05) than that of the negative control. When assessing the possible aneugenic and/or clastogenic damage caused by the drug in CHO cells, we found no difference ( p > 0.05) in the values of micronucleated cells when comparing different diethylpropion treatments and the negative control. Regarding the cell viability, for all the diethylpropion concentrations tested, higher values ( p < 0.05) of apoptosis were found compared with those of the negative control. In relation to the number of necrotic cells, no difference ( p > 0.05) was noted between the means of the three concentrations of diethylpropion evaluated and the negative control. In the experimental conditions, we conclude that diethylpropion has weak genotoxic and cytotoxic activities.

Cytotoxic and antiproliferative effect of tepary bean lectins on C33-A, MCF-7, SKNSH, and SW480 cell lines

For many years, several studies have been employing lectin from vegetables in order to prove its toxic effect on various cell lines. In this work, we analyzed the cytotoxic, antiproliferative, and post-incubatory effect of pure tepary bean lectins on four lines of malignant cells: C33-A; MCF-7; SKNSH, and SW480. The tests were carried out employing MTT and 3[H]-thymidine assays. The results showed that after 24 h of lectin exposure, the cells lines showed a dose-dependent cytotoxic effect, the effect being higher on MCF-7, while C33-A showed the highest resistance. Cell proliferation studies showed that the toxic effect induced by lectins is higher even when lectins are removed, and in fact, the inhibition of proliferation continues after 48 h. Due to the use of two techniques to analyze the cytotoxic and antiproliferative effect, differences were observed in the results, which can be explained by the fact that one technique is based on metabolic reactions, while the other is based on the 3[H]-thymidine incorporated in DNA by cells under division. These results allow concluding that lectins exert a cytotoxic effect after 24 h of exposure, exhibiting a dose-dependent effect. In some cases, the cytotoxic effect is higher even when the lectins are eliminated, however, in other cases, the cells showed a proliferative effect.

In vitro characterization of representative clinical South African Staphylococcus aureus isolates from various clonal lineages

Data concerning the virulence and pathogenesis of South African strains of Staphylococcus aureus are limited. We investigated host–pathogen interactions of randomly selected clinical S. aureus isolates representing various clones. We characterized the ability of isolates to adhere to fibronectin, fibrinogen, collagens IV and VI, to invade host cells and to induce cell death in vitro. We analysed the possible association of these results with characteristics such as methicillin resistance, Panton–Valentine leucocidin (PVL) positivity and clonality. The S. aureus isolates displayed diversity in their abilities to adhere to various human ligands. All isolates were highly invasive except for ST121. PVL-negative isolates were significantly more invasive than the PVL-positive isolates (p 0.004). Isolates of CC5, CC30 and CC121 were non-cytotoxic, whereas isolates of CC22, CC8, CC15, CC45 and CC88 were very cytotoxic. No statistical association was identified between cell death and methicillin resistance, bacterial PVL status, clonality or patient HIV status. The vast majority of isolates were invasive and induced significant cell death. PVL-negative isolates were more invasive than PVL-positive isolates, while methicillin-resistant isolates were not found to be more invasive or cytotoxic than methicillin-susceptible isolates.

Safety evaluation of naringenin upon experimental exposure on rat gastrointestinal epithelium for novel optimal drug delivery

OBJECTIVE

To assess the effect of naringenin on the intestinal biochemical composition, function and histology for gastrointestinal toxicity since it has not yet been adequately exploited for safety through standard assays.

METHODS

Here, we describe naringenin (1 mM, 10 mM and 100 mM, respectively) or sodium deoxycholate (10 mM) effects on isolated brush border membrane from intestinal segments with single pass intestinal perfusion using lactate dehydrogenase, alkaline phosphatase and protein assays. MTT assay was used for cytotoxicity studies. Everted gut sac studies were used for evaluating the transport of nutrients across the intestinal segments. Lucifer yellow was used for paracellular permeability, followed by histological changes and surface characteristic studies of intestinal sacs.

RESULTS

The results indicated no significant alterations with naringenin, although significant (p < 0.01) changes were noticed with sodium deoxycholate in the activity of the rat intestinal brush border associated enzymes such as LDH, followed by intact cell viability with marked decrease in the villi height of the intestinal segments.

CONCLUSIONS

These observations indicate that naringenin was harmless upon exposure to rat gastrointestinal epithelium, clearly demonstrating the potential use of naturally occurring bioflavonoid as safe and novel pharmaceutical adjuvant in oral dosage forms as P-gp inhibitor.

Cerebral edema in children with diabetic ketoacidosis: vasogenic rather than cellular?

Cerebral edema (CE) is accumulation of water in the intracellular or extracellular spaces of the brain. Vasogenic edema occurs when there is breakdown of the tight endothelial junctions of the blood-brain barrier (BBB), leading to extravasation of intravascular protein and fluid into the interstitial space of the brain. In cellular edema the BBB remains intact and there is swelling of astrocytes with corresponding reduction in extracellular space. In this review we bring together clinical evidence from neuropathology and cerebral magnetic resonance (MR) studies in pediatric patients presenting in diabetic ketoacidosis (DKA), and use applied physiology to understand whether CE complicating DKA is vasogenic, rather than cellular in origin. Because the first-line of defense against CE is the interface between the intravascular compartment and the extracellular space in the brain much of the focus in this review is the BBB. The principal pathologic finding in fatal cases is perivascular with BBB disruption and albumin extravasation, suggesting increased vascular permeability. DKA induces an inflammatory response and the mechanism of BBB transcellular permeability may be an immunologic cascade that disrupts tight junctions. The principal MR finding in subclinical cases of CE is vasogenic rather than cellular edema. We propose that the following physiology be considered when treating cases: bolus dose of intravenous mannitol may result in fall in serum sodium concentration, and therefore clinical worsening. Failure to respond to mannitol should prompt the use of 3% hypertonic saline (HS). Bolus dose of intravenous 3% HS is expected to effect vasogenic edema provided that the reflection coefficient is close to 1. Failure to respond to 3% HS should prompt the use of mannitol.

CD8(+) granulomatous cutaneous T-cell lymphoma: a potential association with immunodeficiency

BACKGROUND

Granulomatous cutaneous T-cell lymphoma (G-CTCL) is a rarely encountered entity. Most G-CTCL is CD4(+), with granulomatous mycosis fungoides representing the vast majority of cases. Because of the rarity of CD8(+) G-CTCL, there is a paucity of data regarding the clinicopathologic features and expected course.

OBJECTIVE

To describe the clinical and histopathologic features of G-CTCL.

METHODS

This is a retrospective review of collected cases.

RESULTS

We present 4 cases of CD8(+) G-CTCL. Patients presented with papules and nodules on the trunk and extremities without antecedent patch or plaque disease. In all cases, biopsy specimens were obtained, and these revealed a dense granulomatous infiltrate accompanied by an atypical lymphoid infiltrate of CD8(+) T cells. T-cell clonality studies were positive in 3 of 4 cases. Staging was negative for nodal involvement, but lung granulomas were seen in all cases. In all 4 cases, the patient's medical history was significant for immunodeficiency, either primary or iatrogenic. All 4 patients had slowly progressive disease.

LIMITATIONS

This is a small retrospective case series.

CONCLUSIONS

CD8(+) G-CTCL appears to be associated with immunodeficiency. The finding of a CD8(+) G-CTCL should prompt an evaluation for underlying immunodeficiency. Additional studies are required to validate these conclusions.

Chemical composition, antioxidant, antimicrobial and cytotoxic activities of Tagetes minuta and Ocimum basilicum essential oils

Chemical composition, antioxidant, antimicrobial and cytotoxic activities of Tagetes minuta (TM) essential oil (TMO) and Ocimum basilicum (OB) essential oil (OBO) were examined. The main components for TMO were dihydrotagetone (33.9%), E-ocimene (19.9%), tagetone (16.1%), cis-β-ocimene (7.9%), Z-ocimene (5.3%), limonene (3.1%) and epoxyocimene (2.03%). The main components for OBO were methylchavicol (46.9%), geranial (19.1%), neral (15.15%), geraniol (3.0%), nerol (3.0%), caryophyllene (2.4%). Inhibitory concentrations (IC₅₀) for reactive oxygen species (ROS) and reactive nitrogen species (RNS) scavenging were 12–17 and 200–250 μg/mL of TMO and OBO, respectively. Minimal inhibitory concentration (MIC) against Salmonella typhi,Escherichia coli,Staphylococcus aureus,Bacillus subtilis,Aspergillus niger, and Candida albicans were 150 ± 8, 165 ± 9, 67 ± 8, 75 ± 7, 135 ± 15, and 115 ± 8 μg/mL of TMO, respectively. MIC for S. typhi,E. coli,S. aureus,B. subtilis,A. niger, and C. albicans were 145 ± 8, 160 ± 7, 45 ± 4, 40 ± 3, 80 ± 9, and 95 ± 7 μg/mL of OBO, respectively. IC₅₀ for nasopharyngeal cancer cell line (KB) and liver hepatocellular carcinoma cell line (HepG2) were 75 ± 5 and 70 ± 4 μg/mL of TMO, respectively. IC₅₀ for KB and HepG2 were 45 ± 4 and 40 ± 3 μg/mL of OBO, respectively. Thus, they could be used as an effective source of natural antioxidant and antibacterial additive to protect foods from oxidative damages and foodborne pathogens. Furthermore, they could be promising candidate for antitumor drug design.

Rapid green synthesis of silver nanoparticles from Chrysanthemum indicum L and its antibacterial and cytotoxic effects: an in vitro study

The present work reports a simple, cost-effective, and ecofriendly method for the synthesis of silver nanoparticles (AgNPs) using Chrysanthemum indicum and its antibacterial and cytotoxic effects. The formation of AgNPs was confirmed by color change, and it was further characterized by ultraviolet-visible spectroscopy (435 nm). The phytochemical screening of C. indicum revealed the presence of flavonoids, terpenoids, and glycosides, suggesting that these compounds act as reducing and stabilizing agents. The crystalline nature of the synthesized particles was confirmed by X-ray diffraction, as they exhibited face-centered cubic symmetry. The size and morphology of the particles were characterized by transmission electron microscopy, which showed spherical shapes and sizes that ranged between 37.71-71.99 nm. Energy-dispersive X-ray spectroscopy documented the presence of silver. The antimicrobial effect of the synthesized AgNPs revealed a significant effect against the bacteria Klebsiella pneumonia, Escherichia coli, and Pseudomonas aeruginosa. Additionally, cytotoxic assays showed no toxicity of AgNPs toward 3T3 mouse embryo fibroblast cells (25 μg/mL); hence, these particles were safe to use.

Cytotoxic, antimutagenic, and antioxidant activities of methanolic extract and chalcone dimers (lophirones B and C) derived from Lophira alata (Van Tiegh. Ex Keay) stem bark

The cytotoxic, antimutagenic, and antioxidant activities of methanolic extract and lophirones B and C derived from Lophira alata stem bark were evaluated. The extract and lophirones B and C significantly (P < .05) reduced the viability of Ehrlich ascites carcinoma cells. There were concentration-dependent reduction in 4-nitro-o-aminophenylenediamine and benzo[a]pyrene-induced frame shift mutation as well as aflatoxin B1-induced base pair substitution by the extract and lophirones B and C. The extract and lophirones B and C concentration dependently scavenged DPPH radical, superoxide anion radical, hydrogen peroxide, hydroxyl radicals, and reduced ferric ion in the potassium hexacyanoferrate III reducing system. The results obtained from this study revealed that methanolic extract and lophirones B and C derived from Lophira alata stem bark posses anticancer, antimutagenic, and antioxidant activities, with lophirone C producing the best anticancer, antimutagenic, and antioxidant activities. The acclaimed anticancer activity of Lophira alata may be attributed to lophirones B and C.

Two new sphingolipids from the leaves of Piper betle L

Two new sphingolipids, pipercerebrosides A (1) and B (2), were isolated from the leaves of Piper betle L. Their structures, including absolute configurations, were determined by spectroscopic analysis and chemical degradation. These two compounds did not show significant cytotoxic activity against the cancer cell lines K562 and HL-60 in a MTT assay.

The protective effect of crocin on the amyloid fibril formation of Aβ42 peptide in vitro

Aβ is the main constituent of the amyloid plaque found in the brains of patients with Alzheimer's disease. There are two common isoforms of Aβ: the more common form, Aβ40, and the less common but more amyloidogenic form, Aβ42. Crocin is a carotenoid from the stigma of the saffron flower and it has many medicinal properties, including antioxidant effects. In this study, we examined the potential of crocin as a drug candidate against Aβ42 amyloid formation. The thioflavin T-binding assay and electron microscopy were used to examine the effects of crocin on the extension and disruption of Aβ42 amyloids. To further investigate the relationship between crocin and Aβ42 structure, we analyzed peptide conformation using the ANS-binding assay and circular dichroism (CD) spectroscopy. An increase in the thioflavin T fluorescence intensity upon incubation revealed amyloid formation in Aβ42. It was found that crocin has the ability to prevent amyloid formation by decreasing the fluorescence intensity. Electron microscopy data also indicated that crocin decreased the amyloid fibril content of Aβ. The ANS-binding assay showed that crocin decreased the hydrophobic area in incubated Aβ42. CD spectroscopy results also showed that the peptide undergoes a structural change to α-helical and β-turn. Our study shows that the anti-amyloidogenic effect of crocin may be exerted not only by the inhibition of Aβ amyloid formation but also by the disruption of amyloid aggregates. Therefore, crocin could be essential in the search for therapies inhibiting aggregation or disrupting aggregation.

A Novel Metabolite from Aspergillus ochraceus JGI 25 Showing Cytotoxicity to Hela Cells

This study aims at the isolation of filamentous fungi, extraction of metabolites, and evaluation of the cytotoxic properties on HeLa cells and normal human lymphocytes. We isolated fungi from the soil by serial dilution method. One of the isolates was chosen and identified as Aspergillus ochraceus Wilhelm (Trichocomaceae) by standard techniques. The metabolites were extracted using methanol. Different concentrations of the extract were evaluated for their potential anticancer activity on HeLa cells by 3-(4,5-dimethylthiazol-2yl)-2,5-diphenyl tetrazolium bromide assay and the safety of the extract was checked on normal human lymphocytes. The extract was purified by chromatographic techniques like thin-layer chromatography and high-performance liquid chromatography, and subjected to mass spectrometric analysis. The extract showed significant cytotoxic potential on HeLa cells at low concentrations with a half maximal inhibitory concentration value of <50 μg/ml. The extract gave 10 fractions by thin layer chromatography, and fraction B had higher toxicity than the rest. This fraction gave a single peak by high-performance liquid chromatography and had a mass-to-charge ratio of 905.65, which did not match any of the earlier known fungal metabolites or metabolites from other strains of A. ochraceus. The metabolite from A. ochraceus is alkaloid in nature, cytotoxic to HeLa cells, and appears to be a novel with anticancer potentials, which could be explored further for characterization of the active component.

3-Bromo-1-hydroxy-9,10-anthraquinone (BHAQ) inhibits growth and migration of the human breast cancer cell lines MCF-7 and MDA-MB231

Breast cancer is becoming more prominent in women today. As of now, there are no effective treatments in treating metastatic breast cancer. We have tested the cytotoxic and anti-migration effects of BHAQ, a synthesized anthraquinone, on two breast cancer cell lines, MCF-7 and MDA-MB231. Anthraquinones are an interesting class of molecules that display a wide spectrum of biological applications, including anticancer properties. Cellular inhibition was tested through a MTT assay, double acridine orange/propidium iodide staining and FACS cell cycle analysis. Inhibition of migration was tested by the wound healing method, and migration through a Boyden chamber. BHAQ was cytotoxic towards both cell lines in a dose dependent and possibly cell-dependent manner. Additionally, BHAQ also inhibited the migration of the highly metastatic MDA-MB231 cell line.

Aporphine alkaloids from the leaves of Phoebe grandis (Nees) Mer. (Lauraceae) and their cytotoxic and antibacterial activities

The oxoaporphine alkaloid lysicamine (1), and three proaporphine alkaloids, litsericinone (2), 8,9,11,12-tetrahydromecambrine (3) and hexahydromecambrine A (4) were isolated from the leaves of Phoebe grandis (Nees) Merr. (Lauraceae). Compounds 2 and 3 were first time isolated as new naturally occurring compounds from plants. The NMR data for the compounds 2-4 have never been reported so far. Compounds 1 and 2 showed significant cytotoxic activity against a MCF7 (human estrogen receptor (ER+) positive breast cancer) cell line with IC₅₀ values of 26 and 60 µg/mL, respectively. Furthermore, in vitro cytotoxic activity against HepG2 (human liver cancer) cell line was evaluated for compounds 1-4 with IC₅₀ values of 27, 14, 81 and 20 µg/mL, respectively. Lysicamine (1) displayed strong antibacterial activity against Bacillus subtilis (B145), Staphylococcus aureus (S1434) and Staphylococus epidermidis (a clinically isolated strain) with inhibition zones of 15.50 ± 0.57, 13.33 ± 0.57 and 12.00 ± 0.00 mm, respectively. However, none of the tested pathogenic bacteria were susceptible towards compounds 2 and 3.

In silico study of fucoxanthin as a tumor cytotoxic agent

Background:

Fucoxanthin is a potential tumor cytotoxic compound. However, mechanisms underlying the activities are unclear.

Aim:

This in silico study aimed to predict the main mechanism of fucoxanthin; whether with its binding to p53 gene, CDK2, or tubulin.

Materials and Methods:

In silico was studied by using Autodock-Vina's algorithms. The mechanisms being analyzed by comparison of fucoxanthin and native ligands binding energies in p53 gene (1RV1), CDK2 (1AQ1), and three binding sites of tubulin (1JFF-paclitaxel, 1SA0-colchicine, and 1Z2B-vinblastine site).

Results:

Autodock-Vina's algorithms were valid, as re-docking the native ligands to their receptors showed a RSMD value less than 2 A with binding energies of -11.5 (1RV1), -14.4 (1AQ1), -15.4 (1JFF), -9.2 (1SA0), and -9.7 (1Z2B) kcal/mol. Docking of fucoxanthin to subjected receptors were -6.2 (1RV1), -9.3 (1AQ1), -8.1 (1JFF), -9.2 (1SA0), and -7.2 (1Z2B) kcal/mol. Virtual analysis of fucoxanthin and tubulin binding structure showed the carboxyl moiety in fucoxanthin make a hydrogen bound with 355Val (2.61 A) and 354Ala (2.79 A) at tubulin.

Conclusion:

The results showed that binding energy of fucoxanthin could only reach the same level as with colchicine ligand in tubulin. Therefore, it may predict that the most probable fucoxanthin main mechanism is to bind tubulin, which causes microtubules depolimerization and cell cycle arrest.

Amyloid precursor-like protein 2 suppresses irradiation-induced apoptosis in Ewing sarcoma cells and is elevated in immune-evasive Ewing sarcoma cells

Despite surgery, chemotherapy, and radiotherapy treatments, the children, adolescents, and young adults who are diagnosed with metastasized Ewing sarcoma face a dismal prognosis. Amyloid precursor-like protein 2 (APLP2) has recently been implicated in the survival of cancer cells and in our current study, APLP2's contribution to the survival of Ewing sarcoma cells was examined. APLP2 was readily detected in all Ewing sarcoma cell lines analyzed by western blotting, with the TC71 Ewing sarcoma cells expressing the lowest level of APLP2 among the lines. While irradiation induces apoptosis in TC71 Ewing sarcoma cells (as we determined by quantifying the proportion of cells in the sub-G 1 population), transfection of additional APLP2 into TC71 decreased irradiation-induced apoptosis. Consistent with these findings, in parallel studies, we noted that isolates of the TC71 cell line that survived co-culture with lymphokine-activated killer (LAK) cells (which kill by inducing apoptosis in target cells) displayed increased expression of APLP2, in addition to smaller sub-G 1 cell populations after irradiation. Together, these findings suggest that APLP2 lowers the sensitivity of Ewing sarcoma cells to radiotherapy-induced apoptosis and that APLP2 expression is increased in Ewing sarcoma cells able to survive exposure to cytotoxic immune cells.

The Study of Anticancer and Antifungal Activities of Pistacia integerrima Extract in vitro

Pistacia integerrima Stew. ex Brand (Anacardiaceae) is an ethanobotanically important plant species traditionally used in the treatment of chronic wounds, jaundice, dysentery, etc. The crude extract from Pistacia integerrima and its fractions were tested for cytotoxic activity against Michigan Cancer Foundation-7 human breast cancer cell line. We have also investigated that crude stem extract of this plant also exhibits the antitumour as well as antifungal potential activities. Moreover, we have also studied that the crude extract inhibited Michigan Cancer Foundation-7 cell viability in a dose-dependent manner; the poor toxicity (1.6%) at 10 μg/ml to moderate toxicity (55.4%) at 100 μg/ml. The IC₅₀ values calculated were 90.9 μg/ml. The ethyl acetate and chloroform fractions at a concentration of 200 μg/ml showed ~100 and 97.4% inhibition against Michigan Cancer Foundation-7 cell line, respectively. The crude methanol extract also showed good antitumour (IC₅₀ 125 ppm) activity, but weak antifungal activity. These findings reveal that the ethyl acetate and chloroform fractions of Pistacia integerrima are potent cytotoxic fractions, and could be an alternate candidate for the development of novel biologically active compounds.

Cytotoxic effect and tissue penetration of phenol for adjuvant treatment of giant cell tumours

Local adjuvant treatment of giant cell tumours (GCTs) of the bone with phenol has led to a significant reduction in recurrence rates. In the current study, the optimal phenol concentration and duration of intralesional exposure were evaluated. Specimens of GCTs were exposed to various concentrations of phenol solution (6, 60 and 80%) for either 1 or 3 min. Following embedding in glutaraldehyde, the tumour cell layers were examined by transmission electron microscopy. Destroyed cell organelles indicated the penetration depth as a sign of denaturation. Incubation of GCT specimens with 6% phenol solution for 3 min resulted in the most tissue damage and the deepest tissue penetration of ∼200 μm. Incubation with 60 and 80% phenol solution reached a penetration depth of only ∼100 μm. Phenol instillation may be used for the treatment of small scattered cellular debris following intralesional curettage; however, it is not suitable for treatment of remaining solid tumour tissue of GCT. The use of high phenol concentrations has no benefit and increases the risk of local or systemic intoxication.

Cytotoxic and apoptosis-inducing properties of a C21-steroidal glycoside isolated from the roots of Cynanchum auriculatum

The present study aimed to investigate the anti-cancer effect of a C₂₁-steroidal glycoside (CG) isolated from the roots of Cynanchum auriculatum. CG was able to inhibit the growth of human cancer cells (SGC-7901 cells) in a concentration and time-dependent manner in vitro. SGC-7901 cells exposed to CG (10.8 and 21.6 μM) exhibited typical morphological apoptosis characteristics, such as nuclear-chromatin condensation and apoptotic body formation. Flow cytometric analysis showed that after treatment with CG at 10.8 and 21.6 μM for 24 h, the percentage of apoptotic cells increased to 30.4 and 43.2%, respectively, while the number of cells in the G₀/G₁, S and G₂/M phases of the cell cycle decreased (P<0.05). Furthermore, treatment with CG at a concentration of 21.6 μM for 24 h significantly increased the expression of caspase-3 and the activity of caspase-3 was increased ∼3-fold in SGC-7901 cells. These results suggest that CG is the active anticancer component of the total C₂₁-glycosides of the roots of Cynanchum auriculatum which is able to inhibit the growth of cancer cells and induce cancer cell apoptosis through caspase-3-dependent pathways.

Solid phase versus solution phase synthesis of heterocyclic macrocycles

Comparing a solution phase route to a solid phase route in the synthesis of the cytotoxic natural product urukthapelstatin A (Ustat A) confirmed that a solid phase method is superior. The solution phase approach was tedious and involved cyclization of a ridged heterocyclic precursor, while solid phase allowed the rapid generation of a flexible linear peptide. Cyclization of the linear peptide was facile and subsequent generation of three oxazoles located within the structure of Ustat A proved relatively straightforward. Given the ease with which the oxazole Ustat A precursor is formed via our solid phase approach, this route is amenable to rapid analog synthesis.

Organometallic Palladium Complexes with a Water-Soluble Iminophosphorane Ligand as Potential Anticancer Agents

The synthesis and characterization of a new water-soluble iminophosphorane ligand TPA=N-C(O)-2BrC(6)H(4) (C,N-IM; TPA = 1,3,5-triaza-7-phosphaadamantane) 1 is reported. Oxidative addition of 1 to Pd(2)(dba)(3) affords the orthopalladated dimer [Pd(μ-Br){C(6)H(4)(C(O)N=TPA-kC,N)-2}](2) (2) as a mixture of cis and trans isomers (1:1 molar ratio) where the iminophosphorane moeity behaves as a C,N-pincer ligand. By addition of different neutral or monoanionic ligands to 2, the bridging bromide can be cleaved and a variety of hydrophilic or water-soluble mononuclear organometallic palladium(II) complexes of the type [Pd{C(6)H(4)(C(O)N=TPA-kC,N)-2}(L-L)] (L-L = acac (3); S(2)CNMe(2) (4); 4,7-Diphenyl-1,10-phenanthrolinedisulfonic acid disodium salt C(12)H(6)N(2)(C(6)H(4)SO(3)Na)(2) (5)); [Pd{C(6)H(4)(C(O)N=TPA-kC,N)-2}(L)Br] (L = P(mC(6)H(4)SO(3)Na)(3) (6); P(3-Pyridyl)(3) (7)) and, [Pd(C(6)H(4)(C(O)N=TPA)-2}(TPA)(2)Br] (8) are obtained as single isomers. All new complexes were tested as potential anticancer agents and their cytotoxicity properties were evaluated in vitro against human Jurkat-T acute lymphoblastic leukemia cells, normal T-lymphocytes (PBMC) and DU-145 human prostate cancer cells. Compounds [Pd(μ-Br){C(6)H(4)(C(O)N=TPA-kC,N)-2}](2) (2) and [Pd{C(6)H(4)(C(O)N=TPA-kC,N)-2}(acac)] 3 (which has been crystallographically characterized) display the higher cytotoxicity against the above mentioned cancer cell lines while being less toxic to normal T-lymphocytes (peripheral blood mononuclear cells: PBMC). In addition, 3 is very toxic to cisplatin resistant Jurkat shBak indicating a cell death pathway that may be different to that of cisplatin. The interaction of 2 and 3 with plasmid (pBR322) DNA is much weaker than that of cisplatin pointing to an alternative biomolecular target for these cytotoxic compounds. All the compounds show an interaction with human serum albumin (HSA) faster than that of cisplatin.

Dichloromethane and Methanol Extracts of Scrophularia oxysepala Induces Apoptosis in MCF-7 Human Breast Cancer Cells

PURPOSE

Breast cancer is the most common cause of cancer-related death in women worldwide. Therefore, there is an urgent need to identify and develop therapeutic strategies against this deadly disease. This study is the first to investigate the cytotoxic effects and the mechanism of cell death of Scrophularia oxysepala extracts in MCF-7 human breast cancer cells.

METHODS

Three extracts of Scrophularia oxysepala including the n-hexane, dichloromethane and methanol extracts were examined. MTT (3-(4,5-dimetylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) and Trypan-blue assays were performed in MCF-7 cells as well as Human umbilical vein endothelial cells (HUVEC) to analyze the cytotoxic activity of the extracts of Scrophularia oxysepala. Further, the apoptosis inducing action of the extracts was determined by TUNEL (terminal deoxy transferase (TdT)-mediated dUTP nick- end labeling) test and cell death assay.

RESULTS

The results showed that the n-hexane extract had no cytotoxic effects but dichloromethane and methanol extracts significantly inhibited cell growth and viability in a dose and time dependent manner without inducing damage to non-cancerous cell line HUVEC. In addition, Cell death assay and DNA fragmentation analysis using TUNEL indicated induction of apoptosis by dichloromethane and methanol extracts of Scrophularia oxysepala in MCF-7 cells.

CONCLUSION

Our studies suggest that this plant may contain potential bioactive compound(s) for the treatment of breast cancer.