1,3-Bis(2-chloroethyl)-1-nitrosourea enhances the inhibitory effect of Resveratrol on 5-fluorouracil sensitive/resistant colon cancer cells

AIM:To study the mechanism of 5-fluorouracil(5-FU)resistance in colon cancer cells and to develop strategies for overcoming such resistance by combination treatment.METHODS:We established and characterized a 5-FU resistance(5-FU-R)cell line derived from continuous exposure(25μmol/L)to 5-FU for 20 wk in 5-FU sensitive HCT-116 cells.The proliferation and expression of different representative apoptosis and anti-apoptosis markers in 5-FU sensitive and 5-FU resistance cells were measured by the MTT assay and by Western blotting,respectively,after treatment with Resveratrol(Res)and/or 1,3-Bis(2-chloroethyl)-1-nitrosourea(BCNU).Apoptosis and cell cycle arrest was measured by 4',6'-diamidino-2-phenylindole hydrochloride staining and fluorescence-activated cell sorting analysis,respectively.The extent of DNA damage was measured by the Comet assay.We measured the visible changes in the DNA damage/repair cascade by Western blotting.RESULTS:The widely used chemotherapeutic agents BCNU and Res decreased the growth of 5-FU sensitive HCT-116 cells in a dose dependent manner.Combined application of BCNU and Res caused more apoptosis in5-FU sensitive cells in comparison to individual treatment.In addition,the combined application of BCNU and Res caused a significant decrease of major DNA base excision repair components in 5-FU sensitive cells.We established a 5-FU resistance cell line(5-FU-R)from 5-FU-sensitive HCT-116(mismatch repair deficient)cells that was not resistant to other chemotherapeutic agents(e.g.,BCNU,Res)except 5-FU.The 5-FU resistance of 5-FU-R cells was assessed by exposure to increasing concentrations of 5-FU followed by the MTT assay.There was no significant cell death noted in5-FU-R cells in comparison to 5-FU sensitive cells after5-FU treatment.This resistant cell line overexpressed anti-apoptotic[e.g.,AKT,nuclear factorκB,FLICE-like inhibitory protein),DNA repair(e.g.,DNA polymerase beta(POL-β),DNA polymerase eta(POLH),protein Flap endonuclease 1(FEN1),DNA damage-binding protein 2(DDB2)]and 5-FU-resistance proteins(thymidylate synthase)but under expressed pro-apoptotic proteins(e.g.,DAB2,CK1)in comparison to the parental cells.Increased genotoxicity and apoptosis were observed in resistant cells after combined application of BCNU and Res in comparison to untreated or parental cells.BCNU increased the sensitivity to Res of 5-FU resistant cells compared with parental cells.Fifty percent cell death were noted in parental cells when 18μmol/L of Res was associated with fixed concentration(20μmol/L)of BCNU,but a much lower concentration of Res(8μmol/L)was needed to achieve the same effect in 5-FU resistant cells.Interestingly,increased levels of adenomatous polyposis coli and decreased levels POL-β,POLH,FEN1 and DDB2 were noted after the same combined treatment in resistant cells.CONCLUSION:BCNU combined with Res exerts a synergistic effect that may prove useful for the treatment of colon cancer and to overcome drug resistance.

SYNTHESIS AND ANTITUMOR ACTIVITY OF PEPTIDYL-N^2-HYDROXYMETHYL-5-FLUOROURACIL

Six hydrophobic peptidyl and four amino acid (L-Val, L-Leu, L-Phe, L-Gly) derivatives of 5-fluorouracil(5-FU) were synthesized. The structure of these compounds were characterized by ~1H-NMR, IR, UV spectra and elemental analysis. The antitumor activity was test- ed against EAC cells in vitro.

4-(7-Methoxy-2,2-dimethyl-2,3-dihydrobenzo-furan-5-yl)-N-(pyridin-2-yl)thiazol-2-amine: Chiral Crystal from Achiral Molecule

The title compound 4-（7-methoxy-2,2-dimethyl-2,3-dihydrobenzofuran-5-yl）-N- （pyridin-2-yl） thiazol-2-amine was synthesized by reacting 2-bromo-1-（7-methoxy-2,2-dime- thyl-2,3-dihydrobenzofuran-5-yl）ethanone with 1-（pyridine-2-yl）thiourea, and its crystal was determined by single-crystal X-ray diffraction. The crystal belongs to the monoclinic system, chiral space group C2 with a = 18.1328（14）, b = 5.5969（5）, c = 19.2195（15） A, β= 115.5420（10）°, V= 1759.9（2）A3, Z = 4, F（000） = 744, C19H19N3O2S, Mr= 353.43, Dc= 1.334 g/cm3, S = 1.15, μ = 0.201 mm-1, the final R = 0.035 and wR = 0.111 for 2307 observed reflections （I 〉 2σ（I））. The Flack parameter is -0.03（10）. The preliminary bioassay result indicated that the title compound exhibits strong insecticidal activity （93.75% mortality） against Mythimna separate at the concentration of 1.000 g/L.

Synthesis, Crystal Structure and Antitumor Activity of (E)-1-(7-Methoxy-2,2-dimethyl-2,3-dihydrobenzofuran-5- yl)-3-(2-methoxyphenyl)-2-(1H-1,2,4-triazol-1-yl)propenol

The title compound, （E）-1-（7-methoxy-2,2-dimethyl-2,3-dihydrobenzofuran-5-yl）- 3-（2-methoxyphenyl）-2-（1H-1,2,4-triazol-1-yl）propenol （3a）, was synthesized by the Aldol con- densation reaction of 1-（7-methoxy-2,2-dimethyl-2,3-dihydrobenzofuran-5-yl）-2-（1,2,4-triazol- 1-yl）ethanone with 2-methoxybenzaldehyde and then reduced with NaBH4, and its crystal structure was determined by single-crystal X-ray diffraction： monoclinic system, space group P21 with a = 6.2002（3）, b = 12.8452（7）, c = 13.2257（7） ？, Z = 2, V = 1031.23（9） ？3, Mr = 407.46, Dc = 1.312 Mg/m3, S = 1.054, μ = 0.091 mm-1, F（000） = 432, the final R = 0.0353 and wR = 0.0769 for 3161 observed reflections （I 〉 2σ（I））. X-ray analysis displays that the title compound adopts an E configuration for the C（7）=C（8） double bond and S configuration for the chirality center with the specific rotation of –63.75°. Furthermore, the stability of the crystal was maintained through the intermolecular hydrogen bond O（1）–H？？？N（3）. The antitumor assay exhibits that the title compound 3a （E configuration） has a good antitumor activity against the Hela cell line with the IC50 value of 36.9 μM, which is better than that of 3b （Z configuration）.

Synthesis and Crystal Structure of N1-(2-(4-Bromo-2-nitrophenoxy)-2-dimethyl acyloxymethyl)-5-fluorouracil

The title compound N1-（2-（4-bromo-2-nitrophenoxy）-2-dimethyl acyloxymethyl）-5-fluorouracil（C15H13BrFN3O7, Mr = 446.19） was synthesized and structurally characterized by ^1H-NMR, -（13）C-NMR, ESI-MS and single-crystal X-ray diffraction. The compound crystallizes in triclinic, space group P1, with a = 8.3325（6）, b = 10.1808（13）, c = 11.8194（16） A, α = 73.194（12）, β= 72.351（9）, γ = 89.509（8）o, V = 911.2（2） A^3, Z = 2, T = 300.79（10） K, μ（Cu Kα） = 3.578 mm^-1, Dc = 1.626 g/cm3, F（000） = 448.0, GOF = 1.060, 5723 reflections measured（8.232≤2θ≤139.592°）, 3339 unique（Rint = 0.0184, Rsigma = 0.0254） which were used in all calculations. The final R = 0.0517（I 〉 2s（I）） and wR = 0.1494（all data）. Hydrogen bonds and π-π interactions together stabilize the structure of the molecule. The preliminary biological test shows that the title compound has good antitumor activity against A549 in vitro and lower toxicity to normal cells.

Efficacy of adjuvant XELOX and FOLFOX6 chemotherapy after D2 dissection for gastric cancer

AIM: To compare the efficacy of capecitabine and oxaliplatin (XELOX) with 5-fluorouracil, folinic acid and oxaliplatin (FOLFOX6) in gastric cancer patients after D2 dissection. METHODS: Between May 2004 and June 2010, patients in our gastric cancer database who underwent D2 dissection for gastric cancer at the First Affiliated Hospital of Sun Yat-Sen University were retrospectively analyzed. A total of 896 patients were enrolled into this study according to the established inclusion and exclusion criteria. Of these patients, 214 received the XELOX regimen, 48 received FOLFOX6 therapy and 634 patients underwent surgery only without chemotherapy. Overall survival was compared among the three groups using Cox regression and propensity score matchedpair analyses. RESULTS: Patients in the XELOX and FOLFOX6 groups were younger at the time of treatment (median age 55.2 years; 51.2 years vs 58.9 years), had more undifferentiated tumors (70.1%; 70.8% vs 61.4%), and more lymph node metastases (80.8%; 83.3% vs 57.7%), respectively. Overall 5-year survival was 57.3% in the XELOX group which was higher than that (47.5%) in the surgery only group (P = 0.062) and that (34.5%) in the FOLFOX6 group (P = 0.022). Multivariate analysis showed that XELOX therapy was an independent prognostic factor (hazard ratio = 0.564, P < 0.001). After propensity score adjustment, XELOX significantly increased overall 5-year survival compared to surgery only (58.2% vs 44.2%, P = 0.025) but not compared to FOLFOX6 therapy (48.5% vs 42.7%, P = 0.685). The incidence of grade 3/4 adverse reactions was similar between the XELOX and FOLFOX6 groups, and more patients suffered from hand-foot syndrome in the XELOX group (P = 0.018). CONCLUSION: Adjuvant XELOX therapy is associated with better survival in patients after D2 dissection, but does not result in a greater survival benefit compared with FOLFOX6 therapy.

Argentum 5-Hydroxy-7-methoxy-2-phenyl-4H-chromen-4-one-6-sulfonate:Synthesis,Crystal Structure and Antitumor Activity

In order to improve the water solubility and bioavailability of 5-hydroxy-7-methoxyflavone,argentum 5-hydroxy-7-methoxy-2-phenyl-4H-chromen-4-one-6-sulfonate[Ag4(H2O)6](C(16)H(11)O4SO3)4·H2O(1,C(16)H(11)O4SO3=5-hydroxy-7-methoxy-2-phenyl-4H-chromen-4-one-6-sulfonate)was synthesized by sulfonation reaction.The structure of 1 was characterized by FT-IR,elemental analysis and X-ray single-crystal diffraction.Complex 1 belongs to the triclinic system,space group P1,a=8.077(4),b=12.365(4),c=17.735(7)A,V=1685.0(12)A3,Z=1,μ=1.372 mm^–1,Dc=1.936 g/cm^3,F(000)=984,the final R=0.0819 and wR=0.2332 with I>2σ(I).3D structure of 1 exhibits alternating organic and inorganic regions.O–H×××O hydrogen bonds and Ag–O coordination interactions exist among crystal water,coordinated water and sulfo group,which constructed an organic zone.Flavone skeletons form organic region of 1.Sulfo group is the bridge linking these two regions.The in vitro antitumor activity of 1 against human lymphoma cells U937 and human breast cancer cells MCF-7 were evaluated with CCK-8 assay.The result shows that 1 showed inhibitory activity against tumour cell U937 and MCF-7,and indicated that flavone sulfonate derivatives may be potential leads for further biological screenings and may generate drug-like molecules.

Synthesis and anticancer properties of tungstosilicic polyoxometalate containing 5-fluorouracil and neodymium

A novel tungstosilicic polyoxometalate containing 5-fluorouracil and Nd, K26(C4H4FN2O2)8Nd(SiW11O39)4·5H2O (FNSW) was synthesized and its structure was characterized by using elemental analysis, FT-IR spectra, X-ray powder diffraction, UV-vis spectra and TG. The results indicated that the compound FNSW had Keggin structure of heteropolyanion and ring structure of 5-fluorouracil, and it had a good thermal stability. With 5-fluorouracil for the positive control group, the cytotoxicity tests in human renal embryonic cell HEK293 and the antitumor activity tests in hepatocellular carcinoma cell HepG-2 were carried out by the methyl thiazolyl tetrazolium method. The toxicity of the compound FNSW was lower than that of 5-fluorouracil, and compared with 5-fluorouracil the compound FNSW could inhibit HepG-2 cell in vitro with significant difference. The rare earth element Nd increased the biological activity of polyoxometalate significantly.

Synthesis and antitumor activities of rare earth substituted phosphotungstates containing 5-fluorouracil

Two novel rare earth substituted phosphotungstates containing 5-fluorouracil,K 9（C 4 H 4 FN 2 O 2） 2 Nd（PW 11 O 39） 2 ·25H 2 O（FNdPW） and K 9（C 4 H 4 FN 2 O 2） 2 Ce（PW 11 O 39） 2 ·23H 2 O（FCePW）,were synthesized and characterized by elementary analysis,FT-IR spectra,X-ray powder diffraction and 1 H NMR.The thermal analysis showed that FNdPW decomposed at 210 and 493 oC,and FCePW decomposed at 223 and 471 oC,both of which had good thermal stabilities.MTT tests were performed to study the antitumor activities against HeLa cells and HepG-2 cells of FNdPW,FCePW,5-fluorouracil,C 4 H 4 FN 2 O 2 H 2 PW 12 O 40 ·8H 2 O and K 11 Ln（PW 11 O 39） 2 ·xH 2 O（Ln=Nd,Ce）,and their cytotoxicities against HEK 293 cells.The results showed that FNdPW and FCePW possessed higher antitumor activities and lower cytotoxicities than those of 5-fluorouracil and C 4 H 4 FN 2 O 2 H 2 PW 12 O 40 ·8H 2 O,of which FNdPW exhibited the highest antitumor activates against HeLa cells（EC 50 =3.41×10-6 mol/L） and HepG-2 cells（EC 50 =6.24×10-6 mol/L）.Thus the introduction of rare earth elements and 5-fluorouracil could significantly enhance antitumor effect of polyoxometalates.

Effect of Chemical Doping and Ion Implantation on Cond uctivity of Poly(p-phenylene vinylene) Derivatives

The surface conductivity of poly [ 2-methoxy-5-（3＇-methyl） butoxy]-p-phenylene vinylene （PMOMBOPV） films doped with FeCl3 and H2SO4 by chemical method and implanted by N^＋ ions was studied and the comparison of environmental stability of conductive behavior was also investigated. The energy and dose of N^＋ ions were in the rang 15～35 keV and 3. 8×10^15～9. 6×10^16 ions/cm^2, respectively. The conductivity of PMOMBOPV film was enhanced remarkably with the increases of the energy and dose of N^＋ ions. For example, the conductivity of PMOMBOPV film was 3. 2×10^-2S/cm when ion implantation was performed with an energy of 35 keV at a dose of 9. 6 × 10^14 ions/cm^2 , which was almost seven orders of magnitude higher than that of film unimplanted. The environmental stability of conductive behavior for ionimplanted film was much better than that of chemical doped films. Moreover, the conductive activation energy of ion-implanted films was measured to be about 0.17 eV.

Investigation of Intrachain Exciton Diffusion of MEH-PPV in Solution with Different Polarity

Femtosecond time-resolved transient grating technique was adopted to insight into the intra-chain exciton diffusion of MEH-PPV in solution with different polarity. Broadband white-light continuum was introduced as the probe to observe the transient absorption and the femtosecond time-resolved transient grating information simultaneously. The vibrational dephasing behaviors, single exciton relaxation, and population relaxation dynamics of MEH-PPV were systematically investigated. The result shows that the relaxation processes of the sample solution will be accelerated in the solvent with larger polarity.

Charge Transfer Properties in MEH-PPV/PS:MWCNTs Nanocomposites

The effect of composition and annealing temperature on charge transfer properties, in a donor/acceptor nanocomposites based on poly (2-methoxy-5-(2-ethyhexyl-oxy)-p-phenylenevinylene) (MEH-PPV) and MWCNTs functionalized with Polystyrene (PS:MWCNTs), have been investigated. The quenching of photoluminescence (PL) intensity of pure MEH-PPV, by adding different amounts of functionalized carbon nanotubes, exhibits that a photoinduced charge transfer has been occurred. Charge transfer efficiency was obtained for an acceptable concentration of PS:MWCNTs about 0.5 wt% and at annealed temperature of about 80℃. Quenching efficiency studies imply that MEH-PPV/PS:MWCNTs nanocomposites reveal a high degree of PL quenching, reaching a value of η = 76.9%.

阳桃根中苯醌类化合物的分离鉴定与含量测定

目的：研究阳桃根（ACLR）中苯醌类化学成分的类型及含量测定方法。方法：利用色谱分离法、核磁共振技术对阳桃根药材60％乙醇提取物中的环己烷萃取部位进行分离、鉴定，并应用HPLC法对药材中的苯醌类化学成分进行含量测定。结果：分离得到2个苯醌类化合物：2-methoxy-6-nonyl-cyclohexa．2，5-diene-1，4-dione（MNDD）；2-dodecyl-6-methoxy-cyclohexa-2，5-diene-1，4-dione（DMDD）；MNDD，DMDD分别在0．177～2．657斗g和0．094～1．416μg进样量与峰面积有良好的线性关系；平均加样回收率为98．96％（RSD1．59％），99．55％（RSD0．98％）。结论：首次从植物中分离得到2个苯醌类化合物；HPLC测定方法简便、快速、稳定、准确可靠、重复性好，可用于阳桃根药材中MNDD，DMDD的质量控制。

Update on pharmacotherapy for ocular surface squamous neoplasia

The most frequently encountered non-pigmented tumor of the ocular surface is ocular surface squamous neoplasia(OSSN).Over the past two decades,the pharmacological management of OSSN has grown,with topical 5-fluorouracil,mitomycin,and interferon alpha 2b all being successfully used to treat this disease.Other agents,such as anti-vascular endothelial growth factor(VEGF),retinoic acid,cidofovir and Aloe vera,have less frequently been used in the treatment of OSSN.This review will discuss these pharmacologic agents,summarizing available data and presenting the approach to the treatment of these tumors.

Chemical approaches for mimicking logic functions within fluorescent MPT dyes

The progress of the design, synthesis, fluorescence properties and application of a new family of fluorescent molecular switches towards information processing at the molecular level was reviewed. On the basis of the high fluorescence quantum yields and surroundings-sensitive fluorescent properties of the 5-methoxy-2-(2-pyridyl)-thiazole (2-MPT, 1) and a series of its derivatives as prepared, multiple binary logic and arithmetic functionalities were realized through encoding the controllable fluorescence switching properties with binary digit. Combined with the microfluidic platform, the fabrication of the molecular logic devices was attempted.

New Isoflavonoid Glycosides from the Rhizomes of Iris leptophylla Lingelsh.

Two new isoflavonoid glucosides, 5-hydroxy-6,7-methylenedioxy-isoflavone-4＇-O-D-glucopyranosyl （2→〉l）-L-rhamnoside （irilone-bioside） （compound 1） and 5,4＇-methoxy-6,7-methylenedioxyisoflavone-3＇-O-β-D-glucoside （irisleptophyllidin） （compound 2）, together with five known compounds, nigricanin- 4＇-O-β-D-glucoside （compound 3）, irifloside （compound 4）, irigenin （compound 5）, 5, 3＇, 4＇-trimethoxy-6,7-methylenedioxyisoflavone （compound 6）, and nigricanin （compound 7） were isolated from the alcoholic extract of rhizomes of Iris leptophylla Lingelsh. Their structures were elucidated by spectroscopic methods.