Can phytochemical antioxidant rich foods act as anti-cancer agents?

The search for therapeutic anticancer agents from plant-based foods became the work of numerous researchers when epidemiological studies showed a relationship between the low incidence of cancer and the intake of plant-based foods. These researchers were especially interested in plant-based foods with high antioxidant capacities because of the important role antioxidants have been postulated to play in the prevention and treatment of certain cancers. However, at present there is no conclusive proof that high antioxidant activity is a good indicator of high anticancer activity. This poses a challenge for researchers to directly test this hypothesis and resolve the debate. This review summarized the data on both sides of the debate.     

Modified natural clinoptilolite with quercetin and quercetin dihydrate and the study of their anticancer activity

Natural zeolite of the clinoptilolite type (CT, particle size up to 200 μm) and its modified forms with different content (0.06-5%) of pharmaceutically active compounds (type of flavonoids): quercetin (Q) and quercetin dihydrate (QD) have been investigated by thermal analyses TG, DTA and DTG, FTIR spectroscopy, fluorescence spectroscopy, X-ray powder diffractometry, determination of the surface areas and the pore volumes by low-temperature adsorption of nitrogen and atomic force microscopy. The analyses checked the presence of Q or QD in modified zeolitic products (CTQ and CTQD).Natural zeolite of the clinoptilolite type and their modified forms CTQ and CTQD with low content (0.06% and 1%) of Q and QD have been used for the study of their anticancer activity. Carcinoma cell lines Jurkat, CEM, HeLa, MCF7, A549 and MDA were treated with various amounts of natural clinoptilolite and their modified forms CTQ and CTQD. The water content of the channel system influences the cytotoxicity of zeolite. The results of the study of pure CT thermally activated at two different temperatures 110 and 400 °C confirmed the better cytotoxicity of CT activated at 110 °C (CT110) with higher content of water in comparison with CT activated at 400 °C (CT400). Clinoptilolite modified with quercetin dihydrate (CTQD) has shown better cytotoxicity compared with clinoptilolite modified with quercetin (CTQ).     

Bioactivity and chemical composition of blackcurrant (Ribes nigrum) cultivars with and without pesticide treatment

Eleven blackcurrant cultivars grown with pesticide (PT) and without pesticide treatment (PF) were evaluated to compare the differences in plant growth and physical condition, total anthocyanin content, ascorbic acid content, total antioxidant capacity, effect on prostaglandin E2 (PGE2) production and anticancer cell proliferation activities. Results showed that the yield and growth of PT blackcurrants were higher. However, PF blackcurrants contained a higher amount of ascorbic acid, and displayed an increased inhibition against cancer cells compared to PT blackcurrants, indicating that PF blackcurrants have an increased potential to deliver health-promoting benefit for consumers. Significant differences were observed between blackcurrant cultivars in relation to plant growth and physical condition, total anthocyanin content and PGE2 assay, highlighting the importance of cultivar selection.     

Residual powders from Shochu distillation remnants induce apoptosis in human hepatoma cells via the caspase-independent pathway

Shochu distillation remnants (SDR) are by-products in the manufacturing process of the Japanese liquor Shochu and include various useful organic compounds derived from the fermentation of grains. We have obtained valuable powder (PSDR) from freeze-dried SDR by the treatment with ethanol. In this study, we examined the anticancer effects of barley-, rice-, and sweet potato-PSDR against HepG2 and HuH-7 cells of human hepatocellular carcinoma (HCC) in?vitro. All PSDR inhibited the growth of both these HCC cells through the induction of apoptosis. Especially, barley-PSDR was the most effective for the growth inhibition and apoptosis induction of HCC cells of all PSDR. We next examined the apoptotic mechanisms induced by barley-PSDR. Decrease in mitochondrial membrane potential and release of cytochrome c from mitochondria were observed in HCC cells after the treatment with barley-PSDR. Furthermore, barley-PSDR induced the nuclear translocation of apoptosis-inducing factor (AIF) from mitochondria, while it did not significantly affect the activities of caspase-3, -8, and -9. The results suggested that barley-PSDR induced apoptosis against HCC cells via the caspase-independent mitochondrial pathway. The findings in this study suggest that PSDR has the possibility of therapeutic and/or preventive agents of HCC.     

Curcuma longa and Curcuma mangga leaves exhibit functional food property

Although leaves of Curcuma mangga and Curcuma longa are used in food preparations, the bioactive components in it are not known. In this study, antioxidant, antiinflammatory and anticancer activities of leave extracts and its isolates were investigated using established bioassay procedures in our laboratory. The leaf extracts of both plants gave similar bioassay and chromatographic profiles. The methanolic and water extracts of C. mangga (CMM and CMW) and C. longa (CLM and CLW), at 100 μg/mL, inhibited lipid peroxidation (LPO) by 78%, 63%, 81% and 43%, cyclooxygenase enzymes COX-1 by 55%, 33%, 43% and 24% and COX-2 by 65%, 55%, 77% and 69%, respectively. At same concentration, CMM, CMW, CLM and CLW showed growth inhibition of human tumour cell lines by 0-46%. Therefore, a bioassay-guided isolation of water and methanolic extracts of C. longa was carried out and afforded nine isolates. At 25 μg/mL, these compounds inhibited LPO by 11-87%, COX-1 and -2 enzymes by 0-35% and 0-82% and growth of human tumour cells by 0-36%, respectively.     

杂环基缩胺硫脲的合成及其抗癌活性的研究Ⅱ

研究了结构为Ⅰ的杂环基缩胺硫脲的合成及其抗癌活性。肼、二硫化碳与碘甲烷反应,生成Ⅱ,Ⅱ与2－乙既噻唑反应生成Ⅲ,产率84％。Ⅲ与Ⅰ－取代哌嗪反应生成Ⅰ,产率58％。由NMR谱分析,Ⅲ为两种异构体的混合物,其E／Z约为5／2。Ⅰ经体外筛选表明具有明显的抗癌活性。     

Immunomodulatory and anticancer activities of phenolics from Garcinia mangostana fruit pericarp

The methanolic extract of Garciniamangostana fruit pericarp was partitioned into butanol and water fractions in this work. Three major phenolics were purified and identified as P₁ [1,3,6,7-tetrahydroxy-2,8-(3-methyl-2-butenyl) xanthone], P₂ [1,3,6-trihydroxy-7-methoxy-2,8-(3-methyl-2-butenyl) xanthone] and P₃ (epicatechin). Strong antioxidant activities were detected for P₁–P₃. In vitro cell proliferation trials indicated that P₁ and P₃ exhibited good immunomodulatory activities when 7.5 μg/ml was used. Furthermore, P₁ and P₃ showed good cytotoxicities against human breast cancer cells (MCF-7) and human colon cancer cells (LOVO). P₁ exhibited the maximal cytotoxicity of 73.06% against MCF-7 cells and of 46.27% against LOVO cells when 62.5 μg/ml was used. The cytotoxicities of P₁, P₂, P₃ and paclitaxel against normal embryonic lung fibroblast cells (HELF) were in a decreasing order: paclitaxel > P₃ > P₁ > P_2. These results suggested that P₁ and P₃ could be used as a potential anticancer agent.     

铂类抗癌药物展望

在过去的10年里,铂类抗癌药物取得了重要的进展,又有4种新药,奈达铂、奥沙利铂、舒铂和洛铂相继于1995～2001年成功上市,同时也有多个候选药物因疗效低、毒性大,与顺铂、卡铂比较无优势而在临床试验中被淘汰。目前还有另外9种铂化合物仍在进行临床研究,这些化合物为顺铂和卡铂的类似物、亲脂性配合物、口服铂(Ⅳ)配合物、多核铂配合物以及具有空间位阻的铂配合物。新的铂类抗癌药将在今后10～20年内从那些在临床研究中显示出低毒性、抗癌谱广、与现有药物无交叉耐药性的化合物中产生。     

抗癌新药紫杉醇研究进展

本文介绍了抗癌新药紫杉醇的研究进展,化学性质及药理作用。     

Comparative study between Phragmites australis root and rhizome extracts for mediating gold nanoparticles synthesis and their medical and environmental applications

In this research, we adopt an ecofriendly and sustainable approach to compare the potentiality and efficiency of Phragmites australis aqueous extracts of two different organs to fabricate gold nanoparticles (AuNPs). The aqueous extracts of plant roots and rhizome were used as alternative reducing agents to conventional chemicals. Various Characterization techniques were used; UV–Vis spectroscopy, Zeta potential, Fourier Transform Infrared Spectroscopy (FT-IR), X-ray diffraction (XRD), Selected Area Electron Diffraction (SAED), Energy Dispersive X-ray Spectroscopy (EDX), High Resolution Transmission Electron Microscopy (HRTEM) equipped with elemental mapping in order to confirm the formation of zero-valent AuNPs, X-ray photoelectron spectroscopy (XPS). Our results demonstrated that both extracts of Phragmites australis are good candidates for the green-synthesis of AuNPs. Zeta potential was used to confirm the stability of AuNPs. The cytotoxic capacities of both AuNPs samples were validated using MTT assay which proved the inhibition of the growth and proliferation of human lung cancer cells (A549 cell line). Antioxidant potentialities were >10%. The phytosynthesized AuNPs exhibited high capacity in removing methylene blue and methyl orange dyes within just one min. This research offers an alternative solution to manage the accumulated unwanted biomass of a widely distributed aquatic macrophyte in aquatic ecosystems.