A1 F4/80+LY6CHI MACROPHAGES ARE KEY TO CANCER INITIATION IN COLITIS

Background

Colorectal cancer (CRC) is the third leading cause of cancer death, with a major risk factor being chronic inflammation. Thus, patients with inflammatory bowel disease (IBD) are at an increased risk of CRC. Despite the clear association between inflammation and cancer, the mechanism by which colitis leads to CRC is still not well understood.

Aims

In this study, we aim to explore the mechanism by which inflammation contributes to the initiation of colitis-associated cancer (CAC). We hypothesize that dextran sodium sulfate (DSS)-induced colitis leads to the infiltration of a specific immune cell type associated with tumorigenesis.

Methods

Following an injection of azoxymethane (AOM), mice were treated with the colitis-inducing agents DSS, trinitrobenzene sulfonic acid (TNBS), oxazolone (oxa), Citrobacter rodentium, or Doxorubicin (Doxo). The tumor studies were repeated using our published Cre-dependent murine model of CAC. To generate tamoxifen-inducible Cre transgenic mice that allow for Dclk1+ cell lineage tracing and cell-specific knock-out of the tumor suppressor adenomatous polyposis coli (APC), we crossed our Dclk1CreERT2 mice to both ROSA26tdTomato and APCfl/fl mice (Dclk1/APCfl/fl).

Results

Treatment with DSS, TNBS, oxa, C. rodentium, or Doxo induced colonic inflammation as detected by increased myeloperoxidase (MPO) activity and histologic analysis. DSS administration led to colonic tumors, whereas TNBS, oxa, C. rodentium, or Doxo did not lead to tumorigenesis up to 52 weeks following colitis induction. Upon flow cytometric analysis of several types of immune cells in the colonic tissue, we observed no difference in the number of T and B cells between mice treated with various colitis inducing agents. We did, however, detect significantly increased levels of Ly6G+ neutrophils and F4/80+Ly6Chi macrophages in the DSS-treated mice when compared to mice in the other models of colitis. mRNA and protein array analyses of the colonic tissue, as well as analysis of the RNA-seq data from 206 UC patients (GSE109142), revealed upregulated expression of genes associated with macrophages and neutrophils. Addition of macrophage-produced cytokines, such as IL-1β, TNF-α, or IL-6, induced lineage tracing of Dclk1+ tuft cells in intestinal organoids. Clodronate liposome-mediated depletion of F4/80+Ly6Chi macrophages significantly reduced the number of colonic tumors but did not affect tumor size in Dclk1/APCfl/fl mice.

Conclusions

Our data suggest that infiltration of F4/80+Ly6Chi macrophages, unique to DSS-induced colitis, leads to colonic tumor formation. This demonstrates that specific immune cell types, rather than the presence of colonic inflammation, plays an important role in the initiation of CAC.

Funding Agencies

CAG, CIHR

A16 ROLE OF MYELOID CELLS IN THE INITIATION OF COLITIS-ASSOCIATED COLON CANCER

Background

Colorectal cancer (CRC) is the second leading cause of cancer death, with a major risk factor being chronic inflammation. Despite the clear association between inflammation and cancer, the mechanism by which colitis leads to CRC is not well understood. We recently showed that the presence of inflammation does not always correlate with colonic tumorigenesis, as the type of colitis (i.e. colitis-inducing agent) appears to be important for tumor initiation.

Aims

In this study, we aim to explore the mechanism by which inflammation contributes to the initiation of colitis-associated cancer. We hypothesized that dextran sodium sulfate (DSS)-induced colitis leads to the infiltration of a specific immune cell type that is associated with colonic tumorigenesis.

Methods

To generate tamoxifen-inducible Cre transgenic mice that allow for Dclk1+ cell lineage tracing and cell-specific knock-out of the tumor suppressor adenomatous polyposis coli (APC), we first crossed our transgenic Dclk1CreERT2 mice to both ROSA26tdTomato and APCfl/fl mice (Dclk1/APCfl/fl). Following Tamoxifen induction, mice were treated with the colitis-inducing agents DSS, trinitrobenzene sulfonic acid (TNBS), oxazolone, or Citrobacter rodentium. The tumor studies were repeated using azoxymethane (AOM)-DSS induced colitis-associated cancer model.

Results

Treatment with any of the four colitis-inducing agents (DSS, TNBS, oxazolone, or C. rodentium) induced colonic inflammation as detected by increased myeloperoxidase (MPO) activity and histologic analysis. Interestingly, DSS administration led to colonic tumors, whereas TNBS, oxazolone, or C. rodentium did not, even up to 52 weeks following colitis induction. FACS analysis of immune cells in the colon revealed no difference in the number of T or B cells in mice treated with any of the colitis-inducing agents. We did, however, detect significantly increased levels of Ly6G+ neutrophils and F4/80+ macrophages in DSS-treated mice compared to mice in any of the other three models of colitis. Consistent with this myeloid cell infiltration, significantly upregulated protein levels of G-CSF, IL-6, TNF-α, and CXCL1 were detected in DSS-treated mice compared to the other three models of colitis. IL-1α, IL-1β, IL-4, IL-10, and TGF-β levels were unchanged.

Conclusions

Our data suggest that infiltration of Ly6G+ neutrophils and pro-inflammatory F4/80+ macrophages, unique to DSS-induced colitis, contributes to colonic tumor formation. These data demonstrate that specific immune cell types, rather than the presence of colonic inflammation, play a critical role in the initiation of colitis-associated CRC.

Funding Agencies

CAG, CIHR

P5516Short-term and long-term mortality among acute myocardial infarction patients admitted to hospitals on weekends as compared with weekdays

Background

As in other countries, manpower shortage in weekends and holidays is a common problem in either private hospitals or public hospitals in Taiwan. Whether the manpower shortage in weekends and holidays is associated with poor quality of medical care is a noteworthy subject and several investigations from different countries have been published already.

Purpose

This study examined the difference of short-term and long-term mortality between acute myocardial infraction patients admitted to hospitals on weekends and weekdays in Taiwan.

Methods

We conducted a retrospective, nationwide cohort study based on the National Health Insurance claims database in Taiwan. Adult patients aged 20 years or older who were admitted with a diagnosis of acute myocardial infarction between Jan. 1 2006 and Dec. 31 2014 were identified. Only the first attack of acute myocardial infarction was retained for analysis. The multivariate logistic regression model was applied with adjustment of baseline characteristics at both patient level and hospital level. The outcome variables included in-hospital mortality and one-year cumulative mortality after the index hospitalization.

Results

We identified 53861 patients with acute myocardial infarction as the weekend group, while 130908 patients as the weekday group. The mean age was 68 years old and 68% of the subjects were male in both groups. ST-elevation myocardial infarction constituted 23% of the patients and up to 46% of the subjects underwent percutaneous coronary intervention during the index hospitalization in both groups. Among the weekend group, the in-hospital mortality was 15.8% while the in-hospital mortality was 16.2% in the weekday group (standardized difference = 0.01). The one-year cumulative mortality was 30.2% and 30.9% in the weekend group and the weekday group, respectively (standardized difference = 0.02). The adjusted odds ratio (aOR) concerning in-hospital mortality of the weekend group compared with the weekday group was 0.98 (95% confidence interval [CI]: 0.95–1.01, p=0.11). Also we found no difference in one-year cumulative mortality between the two study groups (aOR = 0.98, 95% CI: 0.96–1.01, p=0.15).

Conclusions

As for acute myocardial infraction patients in Taiwan, admission on weekends or weekdays did not have a significant impact on either in-hospital mortality or one-year cumulative mortality.

Acknowledgement/Funding

Ministry of Science and Technology, the Executive Yuan, Taiwan (MOST 106-2410-H-002-218-, and MOST 107-2410-H-002-237-)

Room-temperature CO Thermoelectric Gas Sensor based on Au/Co3O4 Catalyst Tablet

A carbon monoxide (CO) thermoelectric (TE) gas sensor was fabricated by affixing a Au/Co₃O₄ catalyst tablet on a TE film layer. The Au/Co₃O₄ catalyst tablet was prepared by a co-precipitation and tablet compression method and its possible catalytic mechanism was discussed by means of x-ray diffraction, field emission scanning electron microscopy, high resolution transmission electron microscopy, x-ray photoelectron spectroscopy, temperature-programmed reduction of hydrogen, Fourier transform infrared spectroscopy and Brunauer-Emmett-Teller analysis. The optimal catalyst, with a Au content of 10 wt%, was obtained at a calcination temperature between 200 and 300 °C. The small size of the Au nanoparticles, high specific surface, the existence of Co³⁺ and water-derived species contributed to  high catalytic activity. Based on the optimal Au/Co₃O₄ catalyst tablet, the CO TE gas sensor worked at room temperature and showed a response voltage signal (ΔV) of 23 mV, high selectivity among hydrogen and methane, high stability, and a fast response time of 106 s for 30 000 ppm CO/air. In addition, a CO concentration in the range of 5000-30 000 ppm could obviously be detected and exhibited a linear relationship with ΔV. The CO TE gas sensor provides a promising option for the detection of CO gas at room temperature.

WTC-01, a novel synthetic oxime-flavone compound, destabilizes microtubules in human nasopharyngeal carcinoma cells in vitro and in vivo

BACKGROUND AND PURPOSE

Dynamic polymerization of microtubules is essential for cancer cell growth and metastasis, and microtubule-disrupting agents have become the most successful anti-cancer agents in clinical use. Besides their antioxidant properties, flavonoids also exhibit strong microtubule-disrupting activity and inhibit tumour growth. We have designed, synthesized and tested a series of oxime/amide-containing flavone derivatives. Here we report the evaluation of one compound, WTC-01 for its anti-proliferative effects in human cancer cells.

EXPERIMENTAL APPROACH

We used a range of cancer cell lines including two human nasopharyngeal carcinoma (NPC) cell lines, measuring proliferation, cell cycle and apoptosis, along with caspase levels and mitochondrial membrane potentials. Assays of tubulin polymerisation in vitro and computer modelling of the colchicine binding site in tubulin were also used. In mice, pharmacokinetics and growth of NPC-derived tumours were studied.

KEY RESULTS

WTC-01 was most potent against proliferation of NPC cells (IC50 = 0.45 μM), inducing accumulation of cells in G2 /M and increasing apoptosis, time- and concentration-dependently. The colchicine competition-binding experiments and computer modelling results suggested that WTC-01 causes microtubule disruption via binding to the colchicine-binding site of tubulin resulting in mitochondrial membrane damage and cell apoptosis via activation of caspase-9/-3 without noticeable activation of the caspase-8. Notably, our in vivo studies demonstrated that at doses of 25 and 50 mg·kg(-1) , WTC-01 exhibited good pharmacokinetic properties and completely inhibited the growth of NPC-TW01 cells in a xenograft nude mouse model.

CONCLUSIONS AND IMPLICATIONS

WTC-01, a new synthetic oxime-containing flavone, exhibited potent anti-tumour activity against NPC cells and merits further investigation.

Discovery of oxime-bearing naphthalene derivatives as a novel structural type of Nrf2 activators

Recent studies have demonstrated that oxidative stress insult is one of major causes of tumor formation. Therefore, identify the effective anti-oxidative agents as a preventive approach to stop cancer progression has widely explored. Although, many potent anti-oxidative ingredients in the natural products have been identified but the amount from the nature source hindrances the clinical application. Compound which can activate Nrf2 signaling pathway result unregulated the cellular antioxidant-responses has been demonstrated as an effective chemopreventive approach for cancer treatment. In the present study, certain oxime-bearing naphthalene derivatives were synthesized and evaluated for their Nrf2 activation and anti-proliferative activities. Results indicated (E)-1-(naphthalen-2-yloxy)propan-2-one oxime (11) which increased 2.04-fold Nrf2/ARE-driven luciferase activity was more active than its 1-substituted isomer 10 (1.17-fold) and t-BHQ (1.77-fold), the known Nrf2 activator. The activities were further increased by the replacement of the peripheral methyl group with the phenyl ring in which (Z)-2-(naphthalen-2-yloxy)-1-phenylethanone oxime (13a) exhibited 3.49-fold potency of the positive control. It is worth to mention that compounds 11, 13a, and 13b which showed significant Nrf2 activation are non-cytotoxic to the tested cells with IC50>50μM. This observation strongly suggested that these compounds can be used for chemoprevention. Mechanism studies indicated that these compounds were capable of inducing the phosphorylation of Nrf2 protein at serine 40 which led to the activation of the Nrf2 transcriptional activity.

New pterosin sesquiterpenes and antitubercular constituents from Pteris ensiformis

Two new pterosin sesquiterpenes, (2S)-13-hydroxypterosin A (1) and (2S,3S)-12-hydroxypterosin Q (2), were isolated from the whole plants of Pteris ensiformis, together with six known compounds. The structures of 1 and 2 were determined through extensive 1D/2D-NMR and MS analyses. Compound 2 exhibited antitubercular activity (MIC 6.25 μg/ml) against Mycobacterium tuberculosis H37 Rv in vitro.

New Labdane-type diterpenoids and anti-inflammatory constituents from Hedychium coronarium

Four new labdane-type diterpenoids: hedychicoronarin (1), peroxycoronarin D (2), 7β-hydroxycalcaratarin A (3), and (E)-7β-hydroxy-6-oxo-labda-8(17),12-diene-15,16-dial (4), have been isolated from the rhizomes of Hedychium coronarium, together with 13 known compounds (5–17). The structures of these new compounds were determined through spectroscopic and MS analyses. Compounds 3, 5, 6, and 10 exhibited inhibition (IC₅₀ values ≤4.52 μg/mL) of superoxide anion generation by human neutrophils in response to formyl-L-methionyl-L-leucyl-L-phenylalanine/cytochalasin B (fMLP/CB). Compounds 3–6, 10, and 11 inhibited fMLP/CB-induced elastase release with IC₅₀ values ≤6.17 μg/mL.

Spatial clusters in a global-dependence model

Spatial data often possess multiple components, such as local clusters and global clustering, and these effects are not easy to be separated. In this study, we propose an approach to deal with the cases where both global clustering and local clusters exist simultaneously. The proposed method is a two-stage approach, estimating the autocorrelation by an EM algorithm and detecting the clusters by a generalized least square method. It reduces the influence of global dependence on detecting local clusters and has lower false alarms. Simulations and the sudden infant disease syndrome data of North Carolina are used to illustrate the difference between the proposed method and the spatial scan statistic.

Thymol, benzofuranoid, and phenylpropanoid derivatives: anti-inflammatory constituents from Eupatorium cannabinum

Five new compounds, 9-O-angeloyl-8,10-dehydrothymol (1), 9-(3-methylbutanoyl)-8,10-dehydrothymol (2), eupatobenzofuran (3), 2-hydroxy-2,6-dimethylbenzofuran-3(2H)-one (4), and 1-(2-hydroxy-4-methylphenyl)propan-1,2-dione (5), have been isolated from the aerial part of Eupatorium cannabinum subsp. asiaticum, together with 16 known compounds (6-21). Compounds 6-8, 11, 13, and 15 exhibited inhibition (IC50 values≤18.4 μM) of superoxide anion generation by human neutrophils in response to formyl-L-methionyl-L-leucyl-L-phenylalanine/cytochalasin B (fMLP/CB). Compounds 2, 3, 10, 13, and 15 inhibited fMLP/CB-induced elastase release with IC50 values≤18.3 μM.

Pulmonary toxicity in mice exposed to low and medium doses of water-soluble multi-walled carbon nanotubes

Carbon nanotubes (CNTs) are a class of new allotrope of carbon. Different functionalized CNTs may vary from their physical and chemical properties to the biological property. In this study, the toxicity of water-soluble taurine multi-walled CNTs (tau-MWNTs), raw MWNTs and positive control crystalline silicon dioxide particles on mouse lungs via intratracheal instillation (i.t.) was investigated. The dosages we used were 0.125, 0.25, 0.5 or 1 mg/kg of tau-MWNTs and raw MWNTs, and 1 mg/kg of silicon dioxide particles; Serum and lungs were collected at 1, 7, 14 or 28 days postexposure. The biochemical and cellular parameters were assessed, which include the ratio of the lung weight and body weight (lung indices), lactate dehydrogenase (LDH), alkaline phosphatase (ALP) and angiotensin converting enzyme (ACE) in serum, and malondialdehyde (MDA), reduced glutathione (GSH), total sulfhydryl group (TSH) in lung tissue homogenates as well as the hydroxyproline in lungs. The characteristic recovery of the lung injury at 28 days postexposure was examined by the assessment of LDH, ALP, lung indices, and histopathology. ACE, MDA, GSH, TSH and histopathological changes showed that tau-MWNTs were less toxic than the raw MWNTs. Histopathological and ultrastructural investigation indicated that the acute pulmonary inflammation in lungs alleviated after 7d postexposure, and were greatly recovered within 28d. Meanwhile, the entrapment of tau-MWNTs reduced greatly by the 28d postexposure. Whereas the heavier pathologic changes induced by raw MWNTs lasted 7 days more than that of tau-MWNTs. Notably, no occurrence of granulomas and fibrosis were found in this study both in the two CNTs samples through 28d postexposure. Silicon dioxide particles, on the contrary, produced more severe damage to lungs than CNTs did in lung index, as well as other biochemical and cellular parameters. These findings indicate that water-soluble tau-MWNTs in low and medium doses induce slight and recoverable pulmonary inflammation in mice, and are less toxic than the insoluble raw MWNTs.

Abstract C236: A novel oxime-containing flavone anticancer agent, WTC01, exhibits potent microtubule disruption ability

Flavonoids and its derivatives are common components found in human diet. Several studies indicated flavonoids could benefit in cancer prevention or therapy, but their structure-activity relationships (SAR) remain poorly defined. In order to further understand the SAR, a series of oxime-containing flavone derivatives were designed, synthesized and evaluated for their biological anti-cancer potential. The anti-proliferative ability of these compounds was measured by several human cancer cell lines from different origins including nasopharyngeal cancer (NPC-TW01), leukemia (MT-2) and lung carcinoma (H661). Among over 30 different oxime-containing flavone derivatives, (Z)-6-[2-hydroxyimino-2-(4-methoxyphenyl)ethoxy]-2-phenyl -4H-1- benzopyran-4-one (WTC01) possessed potent activity against NPC-TW01 growth with IC50 of 400 nM. As determined by flow cytometry, WTC01 treatment results in an accumulation of NPC-TW01 cells in G2-M phase following a 6-h exposure with amaximum accumulation observed by 18 h. Furthermore, Annexin-V/propidium iodide (PI) binding assay, Hoechst 33258/PI double staining, and PARP cleavage indicates that cell death proceeded through an apoptotic pathway. Interestingly,WTC01 also causes mitochondrial transmembrane potential loss and activation of caspase-9 and caspase-3 without noticeable activation of the caspase-8. These results suggest that the WTC01-mediated apoptotic signaling pathway depends on the mitochondria and caspase-9/-3 cascades. Further studies showed that WTC01 inhibits microtubule assembly in a concentration-dependent manner, this data suggests that tubulin may serve as the cellular target for WTC01. Taken together, these findings indicated that WTC01, a novel synthetic oxime-containing flavone, exhibits potent activity against cancer growth through the disruption of microtubule and has potential for management of nasopharyngeal malignancies.

Citation Information: Mol Cancer Ther 2009;8(12 Suppl):C236.

First Report of the A2 Mating Type of Phytophthora capsici Infecting Peppers (Capsicum annuum) in Taiwan

Phytophthora capsici Leonion was first identified on pepper (Capsicum annuum L) in Taiwan in 1976. At that time, only the A1 mating type was present (2). In 2007, the A2 mating type of P. capsici was identified on tomato and eggplant in the central part of the country (1). During an excessively rainy period in mid-2008, many chili and sweet pepper fields in Taiwan suffered severe losses due to P. capsici. Symptoms included a foliar blight and stem, root, and fruit rot. Plants eventually wilted and died. Symptomatic plants were collected from chili- and sweet pepper-production areas in central, southern, and eastern Taiwan. Fifty-three isolates from single zoospores were identified by PCR using species-specific primers CAPFW/CAPRV2 (4). Mating type was determined by co-inoculating rape seed agar plates (3) with mycelial plugs of the tester and a known isolate. Pc134, maintained by the mycology unit at The World Vegetable Center, and 27220, provided by P. J. Ann at the Taiwan Agricultural Research Institute, were used as reference isolates of A1 and A2 mating types, respectively. Plates were examined microscopically for oospores after 5 to 7 days of incubation at 24°C in the dark. Of the 53 isolates, 15 were identified as the A2 mating type and the remaining 38 isolates were identified as A1. The A2 mating type was found in the central and southern regions while the A1 mating type was widely distributed across all three regions. The sporangia of the A2 mating type were 60.4 to 73.4 × 40.9 to 51.8 μm (average 69.2 × 44.7 μm), whereas sporangia of the A1 mating type were 50.1 to 73.9 × 37.9 to 48.1 μm (average 61.4 × 44.1 μm). In general, the A2 mating type produced longer sporangia and only a few isolates produced chlamydospores in V8 broth and on agar. To our knowledge, this is the first report of the A2 mating type of P. capsici infecting peppers in Taiwan. The presence of both mating types in the same field has been observed. References: (1) P. J. Ann et al. Plant Pathol. Bull. 17:69, 2008. (2) L. S. Leu and C. W. Kao. Plant Prot. Bull. (Taiwan) 23:59, 1981. (3) M. M. Sautor. Mycologia 59:161, 1967. (4) C. Silvar et al. Eur. J. Plant Pathol. 112:43, 2005.

Multiple factors conferring high radioresistance in insect Sf9 cells

Sf9, a lepidopteran cell line isolated from the fall armyworm, Spodoptera frugiperda, was shown to be significantly more resistant to growth inhibition and apoptosis induction effects of x-ray irradiation than several human cell lines of different origins. The single-cell electrophoresis technique revealed that Sf9 cells showed lower x-ray irradiation-induced DNA damage as well as better efficiency at repairing these damages. In addition, Sf9 cells were lower in both background and x-ray irradiation-induced intracellular oxidative stress, in which the higher intracellular level of reduced glutathione seemed to play a major role. The significance of oxidative stress in determining the radioresistance of Sf9 cells was confirmed by their being more resistant to hydrogen peroxide while equally susceptible to other non-reactive oxygen species of N-nitroso alkylating agents when compared with a human cell line. Although the Sf9 and human cell lines were equally susceptible to the lethal effects of N-nitroso alkylating agents, the components of DNA damage-induced and the repair enzymes involved significantly differ. This phenomenon is also discussed in this report.

First Report of Soybean Pod and Stem Blight Caused by Diaporthe phaseolorum var. sojae in Taiwan

Genera, Diaporthe and Phomopsis, from an important pathogenic complex of soybean (Glycine max) throughout the world, cause reductions in plant stands, yield, and seed health and quality (1). In a study of the Diaporthe/Phomopsis complex in Taiwan in March 2008, four stem samples with black fruiting structures in linear rows on senescent soybean were collected from the research fields at AVRDC, Shanhua, Tainan, Taiwan. Unidentified fungal isolates were obtained by surface disinfection of infected stems and plating excised tissues on potato dextrose agar (PDA). Colonies of the isolates showed ropelike white mycelia with yellowish tonalities. Small and scattered black stromata were observed frequently in the medium. Mutic pycnidia were found solitarily or aggregated in conidiomata on PDA plates after 10 days of incubation at 24°C with a 12-h photoperiod with near-UV light. All isolates produced α-conidia that measured 8.78 × 3.32 (7.00 to11.00 × 3.00 to 4.00) μm, and sporadically, β-conidia of 30.58 × 0.85 (26.00 to 33.00 × 0.60 to 1.20) μm. Perithecia were not observed in the collected stem samples or the fungal cultures on PDA. Restriction fragment length polymorphism patterns of the PCR products amplified by ITS₄ and ITS₅ primers for all isolates were identical to the patterns reported for Diaporthe phaseolorum var. sojae (3). Thus, all isolates were identified as D. phaseolorum var. sojae on the basis of morphologic and genetic characteristics (2,3). Pathogenicity was confirmed through inoculations during the V2 growth stage of soybean seedlings by atomizing conidial suspensions (1 × 10⁷ α-conidia/ml) of each isolate on soybean seedlings as well as by injecting the inoculum into soybean stems separately. Four plants in each of three replications were inoculated for each method and six noninoculated plants served as controls. Plants were incubated in a growth chamber at 25°C and maintaining relative humidity at 100% by a humidifier for 48 h in darkness; thereafter, plants were maintained in the greenhouse at temperatures ranging from 23 to 34°C. Seven days after inoculation, red-brown leaf spots and coalescent lesions were observed on seedlings atomized by inoculum suspensions, as well as brown lesions and black pycnida in linear rows observed on plants inoculated by stem injection. No symptoms were observed on noninoculated plants. The fungal isolates obtained from inoculated soybeans were morphologically identical to those used as inoculum. The pathogenicity test was repeated twice. To our knowledge, this is the first explicit report identifying the causal agent of soybean pod and stem blight in Taiwan. The vouchers of infected specimens are available at AVRDC-The World Vegetable Center. Reference: (1) R. P. Mulrooney. Plant Dis. 70:600, 1988. (2) R. N. Pioli et al. Phytopathology 93:136, 2003. (3) A. W. Zhang et al. Phytopathology 88:1306, 1998.

Phthalides from Pittosporum illicioides var. illicioides with inhibitory activity on superoxide generation and elastase release by neutrophils

Six new phthalides, (S)-3-ethyl-7-hydroxy-6-methoxyphthalide (1), (S)-3-ethyl-7-hydroxy-5,6-dimethoxyphthalide (2), (S)-3-ethyl-5,6,7-trimethoxyphthalide (3), (R)-3-ethyl-7-hydroxy-6-methoxyphthalide (4), (Z)-3-ethylidene-7-hydroxy-6-methoxyphthalide (5), and (Z)-3-ethylidene-6,7-dimethoxyphthalide (6), have been isolated from the root of Pittosporum illicioides var. illicioides, together with seven known compounds. The structures of these new compounds were determined through spectroscopic and MS analyses. Compounds 1-4 exhibited inhibition (IC50<or=29.8 microM) of superoxide anion generation by human neutrophils in response to formyl-L-methionyl-L-leucyl-L-phenylalanine/cytochalasin B (fMLP/CB). Compounds 5 and 6 inhibited fMLP/CB-induced elastase release with IC50 values of 38.6+/-4.3 and 33.9+/-3.9 microM, respectively.

Soy isoflavones supplementation alleviates disease severity in autoimmune-prone MRL-lpr/lpr mice

Soy isoflavones supplements, which are phyto-oestrogens widely used as alternatives to alleviate menopausal syndromes or prevent chronic diseases, may exert oestrogenic and anti-oestrogenic activities. This study aimed to investigate the effects of soy isoflavones supplement on oestrogen-related autoimmune disease, such as systemic lupus erythematosus, using autoimmune-prone female MRL- lpr/lpr mice. Eighty mice of 8 weeks were divided into five groups: 0 (Control), 2 (Isf 2), 10 (Isf 10) and 20 (Isf 20) mg/kg BW/day Phyto SoyaTM isoflavones or 0.375 mg/kg BW/day tamoxifen (TAM) as the positive control, by tube-feeding. Some mice were killed at age 15 weeks for cellular cytokine secretion. The data suggested that the Isf 20 and TAM groups had higher weight gain and survival compared with the control group. At age 22 weeks, the Isf 20 group still had 75% survival comparable to mice treated with TAM. At age 14 weeks, the TAM group showed significantly lower serum anti-double-stranded (ds) DNA IgG and anti-cardiolipin IgG. The mice in the Isf 10 and Isf 20 groups also had lower anti-dsDNA IgG and anti-cardiolipin IgG. The interferon (IFN)-γ secretion from mitogen-stimulated T cells in the Isf 20 and TAM groups were significantly lower than those of control mice. Furthermore, the oestrogenic activity of the methanol extracts of soy isoflavones for oestrogen receptor (ER)β, but not ERα, significantly increased, suggesting that soy isoflavones have a selective modulation of ER activation. Thus, soy isoflavone supplementation did not aggravate murine lupus, but apparently ameliorated the disease.

Role of bone marrow-derived cells in experimental chronic pancreatitis

BACKGROUND

Chronic pancreatitis is a known risk factor for pancreatic adenocarcinoma. Recent work has pointed to a role for bone marrow-derived progenitor cells (BMDCs) in chronic inflammation-based carcinogenesis. Consequently, the role of BMDCs in chronic pancreatitis was investigated.

METHODS

The fate of BMDCs was followed using green fluorescent protein and the Y chromosome as bone marrow markers in gender-mismatched transplanted mice treated with repeated injections of cerulein for up to 45 weeks. The phenotype of engrafted BMDCs was assessed based on the co-expression of bone marrow and pancreatic markers.

RESULTS

After 45 weeks of cerulein treatment, mice developed severe chronic pancreatitis but no preneoplastic lesions. BMDCs did engraft in the pancreas. Most of the BMDCs were desmin positive and contributed to 5.12% (1.12%) (mean (SEM)) of the pancreatic stellate cell population. Pancreatic stellate cells derived from the bone marrow could be activated, as demonstrated by alpha-smooth muscle actin expression, suggesting a role in tissue repair. BMDCs could also be found in pancreatic ducts, based on dolichos biflorus agglutinin and cytokeratin 19 stainings, but at a much lower frequency (0.62% (0.11%)).

CONCLUSION

BMDCs contribute to the pancreatic stellate cell population, suggesting a role in pancreatic tissue repair. In the absence of preneoplastic lesions, BMDCs contribute at a very low level to the ductal epithelium of the chronically inflamed pancreas. The role of BMDCs in pancreatic carcinogenesis remains to be defined.

First Report of the A2 Mating Type of Phytophthora infestans on Tomato Crops in Taiwan, Republic of China

In a study of the Phytophthora infestans population in Taiwan, samples with symptoms typical of late blight were collected from field crops in an important potato- (Solanum tuberosum) and tomato-(Lycopersicon esculentum) production area in the central highlands region. Isolates were obtained by surface disinfecting leaf sections and plating them onto antibiotic-amended rye A agar (1). After subculturing, the pathogen was confirmed as P. infestans on the basis of morphological characters (2). Mating type was determined by co-inoculating unamended rye agar plates with mycelial plugs of the test isolate and a reference P. infestans isolate of either the A1 or A2 mating type (four plates per test isolate, two with different A1, and two with different A2 reference isolates). After incubation (15°C darkness, 7 to 14 days), plates were examined microscopically for the presence of oospores where the colonies interacted. In 2004, one isolate of 200 tested, and in 2006, one isolate of 102 tested, produced oospores only with A1 reference isolates and were concluded to be A2 mating type. In vitro testing showed the two A2 isolates were metalaxyl-resistant (ED₅₀ values >100 mg of metalaxyl per liter on rye grain agar), which is typical of recent P. infestans isolates from potato and tomato in this area (2). Twenty-one single-sporangial isolates from each of the two A2 strains were tested for mating type against two different A1 isolates of P. infestans and confirmed as A2. These isolates were characterized using the techniques described by Deahl et al. (1) and had the allozyme genotype 100/100/111, 100/100 at the loci coding for glucose-6-phosphate isomerase and peptidase, respectively, and were mitochondrial haplotype IIb. This multi-locus genotype is characteristic of recent P. infestans isolates from tomato and potato in Taiwan, but all previous such isolates were A1 mating type and attributed to the US-11 clonal lineage (1). When evaluated on differential hosts, both A2 isolates were tomato race PH-1 and complex potato race R 0,1,2,3,4,7,9,11. RG57 fingerprinting showed that the A2 isolates had fingerprints identical to each other and to A1 P. infestans isolates of the US-11 clonal lineage from tomato in Taiwan (101 011 100 100 110 101 011 001 1). Koch's postulates were completed and the two A2 isolates were found to be highly aggressive on cultivars of potato and tomato. To our knowledge, this is the first report of A2 mating type strains of P. infestans in the field in Taiwan, but currently, their incidence is very low (<1%). One crop from which an A2 isolate was obtained also yielded an A1 isolate, while A1 isolates were obtained from crops in the vicinity of the other. The concurrent presence of the two mating types of P. infestans poses a risk of sexual reproduction and oospore formation in tomato or potato in Taiwan. References: (1) K. L. Deahl et al. Pest Manag. Sci. 58:951, 2002. (2). D. C. Erwin and O. K. Ribeiro, Page 346 in: Phytophthora Diseases Worldwide. The American Phytopathological Society. St. Paul, MN, 1996.

Optically modulated internal strain in InGaN quantum dots grown on SiN(x) nano masks

Optically modulated internal strain has been observed in InGaN quantum dots (QDs) deposited on SiN(x) nano masks. The modulated internal strain can induce a number of intriguing effects, including the change of refractive index and the redshift of InGaN A(1)(LO) phonon. The underlying mechanism can be well accounted for in terms of the variation of internal strain through the converse piezoelectric effect arising from the screening of the internal electric field due to spatial separation of photoexcited electrons and holes. Our results point out a convenient way for the fine tuning of physical properties in nitride-based semiconductor nanostructures, which is very important for high quality optoelectronic devices.

Human gastric cells resistant to (−)-epigallocatechin gallate show cross-resistance to several environmental pollutants

After a long-term culture in (-)-epigallocatechin gallate (EGCG, 20 microM), a major constituent of green tea, human gastric AGS cells developed 2.2-fold resistance to EGCG. The resistant AGS (AGS-R) cells were cross-resistant to several N-methylcarbamate insecticides, which are among the major control agents for pest insects in Taiwan. The AGS-R cells also showed protective effects against both the cytotoxicity and DNA damage induced by one of the mutagenic derivatives of N-methylcarbamate insecticide, N-nitroso methomyl, which is known to target the mammalian gastric tract. Therefore, acquisition of resistance by AGS cells through chronic exposure to EGCG implies that the tea-drinking habit of the Taiwanese is probably beneficial for the health of the gastric tract. In addition, AGS-R cells were cross-resistant to sodium arsenite and hydrogen peroxide, indicating that tolerance to oxidative stress might play a role in the development of resistance described in this investigation.

Synthesis, antiproliferative, and antiplatelet activities of oxime- and amide-containing quinolin-2(1H)-one derivatives

Certain oxime- and amide-containing quinolin-2(1H)-one derivatives were synthesized and evaluated for their antiproliferative and antiplatelet activities. These compounds were synthesized via alkylation of hydroxyl precursors followed by the reaction with NH(2)OH or NaN(3) (Schmidt reaction). The preliminary assays indicated that amide derivatives are either weakly active or inactive while the oxime counterparts exhibited potent inhibitory activities against platelet aggregation induced by collagen, AA (arachidonic acid), and U46619 (the stable thromboxan A(2) receptor agonist). Among them, (Z)-6-[2-(4-methoxyphenyl)-2-hydroxyiminoethoxy]quinolin-2(1H)-one (7c) was the most active against AA induced platelet aggregation with an IC(50) of 0.58microM and was inactive against cell proliferation. For the inhibition of U46619 induced aggregation, 7a and 8a-c exhibited very potent activities with IC(50) values in a range between 0.54 and 0.74microM. For the antiproliferative evaluation, N-(biphenyl-4-yl)-2-(2-oxo-1,2-dihydroquinolin-7-yloxy)acetamide (11d) was the most potent with GI(50) values of <10, 10.8, and <10microM against the growth of MT-2, NCI-H661, and NPC-Tw01, respectively, and possessed only a weak antiplatelet activity. Further evaluation of 11d as a potential anticancer agent is on-going.

Hypergastrinemia increases gastric epithelial susceptibility to apoptosis

Plasma concentrations of the hormone gastrin are elevated by Helicobacter pylori infection and by gastric atrophy. It has previously been proposed that gastrin acts as a cofactor during gastric carcinogenesis and hypergastrinemic transgenic INS-GAS mice are prone to developing gastric adenocarcinoma, particularly following H. pylori infection. We hypothesised that the increased risk of carcinogenesis in these animals may partly result from altered susceptibility of gastric epithelial cells to undergo apoptosis. Gastric corpus apoptosis was significantly increased 48 h after 12Gy gamma-radiation in mice rendered hypergastrinemic by transgenic (INS-GAS) or pharmacological (omeprazole treatment of FVB/N mice) methods and in both cases the effects were inhibited by the CCK-2 receptor antagonist YM022. However, no alteration in susceptibility to gamma-radiation-induced gastric epithelial apoptosis was observed in mice overexpressing progastrin or glycine-extended gastrin. Apoptosis was also significantly increased in gastric corpus biopsies obtained from H. pylori-infected humans with moderate degrees of hypergastrinemia. We conclude that hypergastrinemia specifically renders cells within the gastric corpus epithelium more susceptible to induction of apoptosis by radiation or H. pylori. Altered susceptibility to apoptosis may therefore be one factor predisposing to gastric carcinogenesis in INS-GAS mice and similar mechanisms may also be involved in humans.

28-Day oral toxicity study of the aqueous extract from spider brake (Pteris multifida Poiret) in rats

Spider brake (Pteris multifida Poiret) is a very important folk herb and a constituent in most of the traditional herbal beverage formulas in Taiwan; however, little toxicological information is available regarding the safety following repeated exposure. The present study was conducted to evaluate the toxicity of aqueous extract from spider brake (SB) in Sprague-Dawley rats on dietary oral gavage at concentrations of 100, 500, and 1000 mg/kg b.w. day for 28 days. There were no adverse effects on general condition, growth, feed and water consumption, feed conversion efficiency, red blood cell and clotting potential parameters, clinical chemistry values, and organ weights except for neutrophils and lymphocytes being slightly diminished in male and female rats at the highest dose, respectively. Necropsy and histopathology findings revealed no treatment-related changes in any of the organs. The results obtained in this study allowed us to conclude that the SB properly utilized in the traditional oral administration could be devoid of any toxic risk.

Free radical-scavenging activity of aqueous extract of Pteris multifida Poiret

Aqueous extract of Pteris multifida showed scavenging activities on DPPH, hydroxyl radicals and reducing power.

Efficacy of caspofungin against Aspergillus flavus, Aspergillus terreus, and Aspergillus nidulans

The echinocandin caspofungin is a potent inhibitor of the activity of 1,3-beta-D-glucan synthase from Aspergillus flavus, Aspergillus terreus, and Aspergillus nidulans. In murine models of disseminated infection, caspofungin prolonged survival and reduced the kidney fungal burden. Caspofungin was at least as effective as amphotericin B against these filamentous fungi in vivo.

A new cytotoxic amide from the stem wood of Hibiscus tiliaceus

A new coumarin, hibiscusin, and a new amide, hibiscusamide, together with eleven known compounds including vanillic acid, P-hydroxybenzoic acid, syringic acid, P-hydroxybenzaldehyde, scopoletin, N- trans-feruloyltyramine, N-cis-feruloyltyramine, a mixture of beta-sitosterol and stigmasterol, a mixture of beta-sitostenone and stigmasta-4,22-dien-3-one were isolated from the stem wood of Hibiscus tiliaceus. The structures of these new compounds were determined through spectral analyses. Among the isolates, three compounds exhibited cytotoxicity (IC (50) values < 4 microg/mL) against P-388 and/or HT-29 cell lines in vitro.

The gastrin gene promoter is regulated by p73 isoforms in tumor cells

p73, a new p53 family member, is a transcription factor that is increasingly recognized in cancer research as an important player in tumorigenesis as well as in chemotherapeutic drug sensitivity. Despite the substantial structural and functional similarities to p53, accumulating evidence suggests that p53 and p73 may differently regulate their transcriptional targets. In this study, we have investigated the role of p73 in regulation of the gastrin gene promoter. Gastrin is a peptide hormone and an important factor in determining the progression of a number of human malignancies. Our results show that p73 can bind to the gastrin promoter. This leads to transcriptional upregulation of gastrin mRNA. We also found that the levels of gastrin and p73 transcripts correlate in primary gastric tumors. Taken together, our results demonstrate a novel mechanism for regulation of gastrin gene transcription and support a concept that p53 and p73 may have different biological roles in tumors.

First Report of Race 2 of Fusarium oxysporum f. sp. lycopersici, the Causal Agent of Fusarium Wilt on Tomato in Taiwan

Fusarium wilt caused by Fusarium oxysporum Schlechtend.:Fr. f. sp. lycopersici (Sacc.) W.C. Snyder & N.H. Hans. is a destructive disease of tomato crops worldwide. The use of resistant varieties is the best strategy for disease control. There are three reported races of the pathogen. Recent surveys indicated that many of the commercial cultivars with resistance to F. oxysporum f. sp. lycopersici race 1 planted in Taiwan displayed Fusarium wilt symptoms. Yellowing on the older leaves was observed on one side of the stems close to fruit maturity. The yellowing gradually affected most of the foliage and was accompanied by wilting of the plants. The vascular tissue was usually dark brown and discoloration extended to the apex. The wilting became more extensive until plants collapsed and died. A total of 87 isolates obtained from typical diseased plants throughout Taiwan from 2002 to 2005 were analyzed to determine the race and distribution of this pathogen in Taiwan. Isolates were confirmed at the species level using F. oxysporum-specific primers FOF1 and FOR1 (4). Subsequently, isolates were characterized for pathogenicity, race and restriction fragment length polymorphisms of the intergenic spacer region of rDNA (IGS-RFLP) with two reference isolates, Fol 11A (race 1) and Fol 34-1 (race 2). Pathogenicity tests and race determination were conducted using root-dip inoculation (3) on 2-week-old seedlings of host differentials Bonny Best (no resistance), UC82-L (resistant to race 1), and Florida MH-1 (resistant to races 1 and 2). Thirty-six seedlings of each cultivar were arranged into three replications and inoculated with each isolate. Disease reaction was evaluated 3 weeks after inoculation. The disease severity rating (DSR) was determined on individual plants according to the following scale: 0 = plant healthy without external symptoms; 1 = slight vascular discoloration with or without stunted growth; 2 = severe vascular discoloration usually with stunted growth; and 3 = plant wilted beyond recovery or dead. The presence of severe vascular discoloration indicated a susceptible reaction. All isolates were race 2, and over 70% of the isolates showed strong virulence with a DSR >2 on cvs. Bonny Best and UC-82L. This result was different from a previous report of race 1 from Taiwan (2). Two IGS-RFLP haplotypes generated by EcoRI, RsaI, and HaeIII digestions (1) were identified. Eighty-six isolates displayed one banding pattern, and one unique isolate displayed a second banding pattern. The results demonstrated the predominance of race 2 and low diversity within the Taiwan population. To our knowledge, this is the first report regarding the predominant race and IGS-RFLP haplotype identification of F. oxysporum f. sp. lycopersici in Taiwan. Our study indicates that tomato varieties in Taiwan should possess resistance to race 2. References: (1) G. Cai et al. Phytopathology 93:1014, 2003. (2) K. S. Elias and R. W. Schneider. Phytopathology 82:1421, 1992. (3) J. W. Gerdemann and A. M. Finley. Phytopathology 41:238, 1951. (4) P. K. Mishra et al. FEMS Microbiol. Lett. 218:329, 2003.

Synthesis, antiproliferative, and antiplatelet activities of oxime- and methyloxime-containing flavone and isoflavone derivatives

Certain oxime- and methyloxime-containing flavone and isoflavone derivatives were synthesized and evaluated for their antiproliferative activity against three solid cancer cells, human cervical epithelioid carcinoma (HeLa), hepatocellular carcinoma (SKHep1), and oral squamous cell carcinoma (SAS), which are commonly seen in Asian countries, including Taiwan. Selective compounds were also evaluated in the full panel of 60 human tumor cell lines and their mean GI50 values were obtained. The preliminary assays indicated flavone-6-yl derivatives are the most cytotoxic while isoflavone-7-yl derivatives are the best antiplatelet agents. Among them, (E)-6-(2-methoxyiminopropoxy)-2-phenyl-4H-1-benzopyran-4-one (14), (Z)-6-(2-hydroxyimino-2-phenylethoxy)-2-phenyl-4H-1-benzopyran-4-one (18a), and (Z)-6-[2-hydroxyimino-2-(4-methoxyphenyl)ethoxy]-2-phenyl-4H-1-benzopyran-4-one (18c) are three of the best antiproliferative agents with GI50 values of 0.8, 0.7, and 0.8 microM, respectively, against the growth of SKHep1; 0.9, 0.8, and 1.0 microM, respectively, against the growth of HeLa cells. Compound 18c is not only the most cytotoxic with a mean GI50 value of 0.08 microM against the full panel of 60 human tumor cell lines but also the only flavone derivative that exhibited a GI50 value of less than 1 microM against the growth of SAS. Flow cytometric analyses revealed that growth inhibition by 18c was due to accumulation in G2/M phase arrest and followed by apoptosis.

Role of breast tumour kinase in the in vitro differentiation of HaCaT cells

BACKGROUND

Breast tumour kinase (BRK) is a newly identified non-receptor protein tyrosine kinase from a metastatic breast tumour. Its biological functions are still under extensive investigation. The mouse homologue Sik (Src-related intestinal kinase) has been implicated in mouse keratinocyte differentiation; however, not much is known about the functions of BRK in human cutaneous biology.

OBJECTIVES

Using HaCaT cells as an experimental model, to explore the mutual relationships between BRK and differentiation of human keratinocytes.

METHODS

Archival paraffin blocks of normal and pathological skin were retrieved for examining the in vivo distribution of BRK. Its expression and subcellular localization were examined via indirect immunofluorescence, and quantitative changes were analysed by Northern and Western blots. The kinase activity of BRK was determined by its autophosphorylation and phosphorylation of exogenous substrate in the in vitro kinase assay. Using a retroviral infection method, we established stably transfected HaCaT cells expressing vector, wild-type BRK or a kinase-defective mutant (K219M). Expression of the differentiation marker keratin 10 (K10) was compared among these cells using semiquantitative reverse transcription-polymerase chain reaction. Results Histochemical examination showed that BRK was expressed exclusively in suprabasal keratinocytes. Its distribution was both cytoplasmic and intranuclear. An enhanced regional suprabasal expression pattern was observed in the confluent areas of cell cultures. The expression of BRK transcript and protein was up-regulated in prolonged confluence culture in a serum-dependent manner. Its kinase activity was activated shortly after the addition of calcium and ionomycin and returned to the basal level within 30 min. Overexpression of wild-type BRK moderately promoted the expression of K10 transcript while the kinase-defective BRK mutant exerted a prominent suppressive effect.

CONCLUSIONS

The in vivo distribution of BRK and its up-regulation during in vitro differentiation of HaCaT cells, together with the activation of its kinase activity by calcium/ionomycin and its influence on K10 expression, all indicate a role for BRK in the complex process of keratinocyte differentiation.

Synthesis, antiproliferative, and vasorelaxing evaluations of coumarin α-methylene-γ-butyrolactones

Certain coumarin alpha-methylene-gamma-butyrolactones were synthesized and evaluated for antiproliferative and vasorelaxing activities. These compounds were synthesized via alkylation of hydroxycoumarins 2a-f followed by oxidation and the Reformatsky-type condensation. The results of this study are as follows (1) for the vasorelaxing activity, coumarin-7-yl alpha-methylene-gamma-butyrolactone 6d, with an IC50 value of 9.4 microM against pig coronary arterial contraction induced by KCl, is a more active vasorelaxant than its coumarin-4-yl counterpart 6a and its gamma-methyl congener 1. A methyl group substituted at C-4 of the coumarin-7-yl moiety reduced the vasorelaxing effect (6d vs 6e) while the 3,4,8-trimethyl derivative 6f was inactive. (2) For the antiproliferative activity, coumarin-4-yl alpha-methylene-gamma-butyrolactone 6a, which exhibited the most potent antiproliferative activity on the growth of MCF7, NCI-H460, and SF-268 with IC50 values of 6.97, 14.68, and 8.36 microM, respectively, is more cytotoxic than its coumarin-7-yl counterpart 6d and the 6,7-dimethyl derivative 6b. For the coumarin-7-yl derivatives, 6d is more active than its gamma-methyl congener 1, indicating that substitution at the gamma-position decreased cytotoxicity.

Simulation of apparent infection rate to predict severity of soybean rust using a fuzzy logic system

ABSTRACT Few biologically based models to assess the risk of soybean rust have been developed because of difficulty in estimating variables related to infection rate of the disease. A fuzzy logic system, however, can estimate apparent infection rate by combining meteorological variables and biological criteria pertinent to soybean rust severity. In this study, a fuzzy logic apparent infection rate (FLAIR) model was developed to simulate severity of soybean rust and validated using data from field experiments on two soybean cultivars, TK 5 and G 8587. The FLAIR model estimated daily apparent infection rate of soybean rust and simulated disease severity based on population dynamics. In weekly simulation, the FLAIR model explained >85% of variation in disease severity. In simulation of an entire epidemic period, the FLAIR model was able to predict disease severity accurately once initial values of disease severity were predicted accurately. Our results suggest that a model could be developed to determine apparent infection rate and an initial value of disease severity in advance using forecasted weather data, which would provide accurate prediction of severity of soybean rust before the start of a season.

Synthesis and anticancer evaluation of certain 4-anilinofuro[2,3-]quinoline and 4-anilinofuro[3,2-]quinoline derivatives

Certain linear 4-anilinofuro[2,3-b]quinoline and angular 4-anilinofuro[3,2-c]quinoline derivatives were synthesized and evaluated in vitro against the full panel of NCI's 60 cancer cell lines. For the linear 4-anilinofuro[2,3-b]quinoline derivatives, 1-[4-(furo[2,3-b]quinolin-4-ylamino)phenyl]ethanone (5a) is the most cytotoxic with a mean GI50 value of 0.025 microM. Substitution at either furo[2,3-b]quinoline ring (2a, 2b, and 5b) or 4-anilino moiety (3-7) led to a decrease of cytotoxicity. For the angular 4-anilinofuro[3,2-c]quinoline derivatives, (E)-1-[3-(furo[3,2-c]quinolin-4-ylamino)phenyl]ethanone oxime (14a) exhibited potent inhibitory activities on UO-31, UACC-257, and UACC-62, with GI50 values of 0.03,<0.01, and<0.01 microM respectively. The same cytotoxicity profile was observed for its methyl counterpart, 14b, in which the GI50 values against UO-31, UACC-257, and UACC-62 was<0.01, 0.04 and<0.01 microM respectively. These results deserve full attention especially because 14a and 14b are relatively non-cytotoxic with the mean GI50 value of 7.73 and 8.91 microM respectively.