Plant derived substances with anti-cancer activity: from folklore to practice

Plants have had an essential role in the folklore of ancient cultures. In addition to the use as food and spices, plants have also been utilized as medicines for over 5000 years. It is estimated that 70-95% of the population in developing countries continues to use traditional medicines even today. A new trend, that involved the isolation of plant active compounds begun during the early 19th century. This trend led to the discovery of different active compounds that are derived from plants. In the last decades, more and more new materials derived from plants have been authorized and subscribed as medicines, including those with anti-cancer activity. Cancer is among the leading causes of morbidity and mortality worldwide. The number of new cases is expected to rise by about 70% over the next 2 decades. Thus, there is a real need for new efficient anti-cancer drugs with reduced side effects, and plants are a promising source for such entities. Here we focus on some plant-derived substances exhibiting anti-cancer and chemoprevention activity, their mode of action and bioavailability. These include paclitaxel, curcumin and cannabinoids. In addition, development and use of their synthetic analogs, and those of strigolactones, are discussed. Also discussed are commercial considerations and future prospects for development of plant derived substances with anti-cancer activity

Derivation of species-specific hybridization-like knowledge out of cross-species hybridization results

BACKGROUND: One of the approaches for conducting genomics research in organisms without extant microarray platforms is to profile their expression patterns by using Cross-Species Hybridization (CSH). Several different studies using spotted microarray and CSH produced contradicting conclusions in the ability of CSH to reflect biological processes described by species-specific hybridization (SSH). RESULTS: We used a tomato-spotted cDNA microarray to examine the ability of CSH to reflect SSH data. Potato RNA was hybridized to spotted cDNA tomato and potato microarrays to generate CSH and SSH data, respectively. Difficulties arose in obtaining transcriptomic data from CSH that reflected those obtained from SSH. Nevertheless, once the data was filtered for those corresponding to matching probe sets, by restricting proper cutoffs of probe homology, the CSH transcriptome data showed improved reflection of those of the SSH. CONCLUSIONS: This study evaluated the relative performance of CSH compared to SSH, and proposes methods to ensure that CSH closely reflects the biological process analyzed by SSH

Suitability of mycorrhiza-defective mutant/wildtype plant pairs (Solanum lycopersicum L. cv Micro-Tom) to address questions in mycorrhizal soil ecology

Despite the importance of arbuscular mycorrhizal fungi (AMF) to ecosystem processes, few experimental tools are available to quantify AMF contributions to process rates. In this study we examine the efficacy of an experimental system consisting of wildtype (WT) and different non-mycorrhizal (Myc−) genotype pairs of tomato (Solanum lycopersicum L.), specifically focusing on cv Micro-Tom. Two conditions necessary to make such a system useful were examined; (1) that the Myc− genotype(s) do not get colonized in a full soil AMF community background, while the WT does, and B) that there are no non-target effects of the Myc− phenotype on soil microbes. We assessed the second condition by growing Myc− genotypes and WT in non-mycorrhizal soil, monitoring plant growth (root, shoot biomass; root length; root diameter size distribution) and soil microbial community structure (PLFA analysis) as indicators of any changes in root tissue quality or rhizodeposition. All tested Myc− genotypes showed a drastically reduced colonization in mycorrhizal soil. However, in non-mycorrhizal soil, M161 had greater root biomass and M20 greater microbial biomass compared to WT. Only one of the Myc− mutants examined fully met the criteria. We conclude that the BC1/WT pair is a powerful experimental system and recommend caution when using Myc− mutants in mycorrhizal ecology

Effects of Baking, Roasting and Frying on Total Polyphenols and Antioxidant Activity in Colored Chickpea Seeds

ABSTRACT Chickpea lines with colored testa (seed coat) contain high levels of polyphenolic compounds that exhibit high levels of antioxidant activity. In a previous study, we showed that common processing procedures, such as soaking and cooking, decrease the levels of these bioactive compounds and subsequent overall antioxidant activity. The observed reduction in total phenolic content was due to the movement of polyphenols from the seed coat to the soaking or cooking water. Here, the effects of baking, roasting and frying processes were examined in relation to total phenolic content (TPC), total flavonoid content (TFC) and ferric-reducing ability of plasma antioxidant activity (FRAP AA) of colored chickpea seeds. Baked, fried and roasted colored chickpea seeds had significantly higher levels of TPC, TFC and FRAP AA than regular cream-and beige-colored seeds subjected to the same treatments. In contrast to our previous results with soaking and cooking, baking, frying and roasting retained most of the TPC, TFC and FRAP AA in the final products. Thus, colored chickpeas subjected to these three processing methods might be considered a functional food in addition to its traditional role of providing dietary proteins

Strigolactone analogs act as new anti-cancer agents in inhibition of breast cancer in xenograft model

Strigolactones (SLs) are a novel class of plant hormones. Previously, we found that analogs of SLs induce growth arrest and apoptosis in breast cancer cell lines. These compounds also inhibited the growth of breast cancer stem cell enriched-mammospheres with increased potency. Furthermore, strigolactone analogs inhibited growth and survival of colon, lung, prostate, melanoma, osteosarcoma and leukemia cancer cell lines. To further examine the anti-cancer activity of SLs in vivo, we have examined their effects on growth and viability of MDA-MB-231 tumor xenografts model either alone or in combination with paclitaxel. We show that strigolactone act as new anti-cancer agents in inhibition of breast cancer in xenograft model. In addition we show that SLs affect the integrity of the microtubule network and therefore may inhibit the migratory phenotype of the highly invasive breast cancer cell lines that were examined