Induction of Apoptosis in Jeko-1 Mantle Cell Lymphoma Cell Line by Resveratrol: A Proteomic Analysis

Phytostilbenes in lymphoma: Focuses on the mechanistic and clinical prospects of resveratrol, pterostilbene, piceatannol, and pinosylvin

Lymphoma is a cancer affecting the lymphatic system that fights infections and diseases. In addition to surgery, radiotherapy, and chemotherapy, novel approaches have recently been investigated, such as phytostilbenes in treating lymphoma. Phytostilbenes are natural compounds present in various plants and have been shown to have different therapeutic effects, including anticancer properties. Resveratrol is a main phytostilbene with various derivates followed by pterostilbene and piceatannol. Studies have revealed that phytostilbenes can suppress the growth and proliferation of lymphoma cells by inducing apoptosis and inhibiting specific enzyme activity in cancer cell survival. The compounds also have antiinflammatory effects contributing to reducing lymphoma-associated inflammation. Additionally, phytostilbenes have been shown to increase the immune system's ability to fight cancer cells by activating immune cells (T-cells and natural killer cells). This review investigates the potential therapeutic effects of phytostilbenes, including resveratrol, pterostilbene, piceatannol, and pinosylvin, against lymphoma.

Rationale for assessing the therapeutic potential of resveratrol in hematological malignancies

Promising results from pre-clinical studies on the naturally-occurring polyphenol resveratrol have generated considerable interest and somewhat excessive expectations regarding the therapeutic potential of this compound for treating or preventing various diseases, including cardiovascular and neurodegenerative disorders and cancer. Resveratrol has potent inhibitory activity in vitro against various tumor types, including cell lines derived from virtually all blood malignancies. Pharmacological studies have shown that resveratrol is safe for humans but has poor bioavailability, due to its extensive hepatic metabolism. Curiously, a substantial proportion of the orally administered resveratrol can reach the bone marrow compartment. Notably, various pathways dysregulated in blood cancers are known to be molecular targets of resveratrol, thus substantiating the potential utility of this agent in blood malignancies. In this review, we primarily focus on the scientific evidence that supports the potential utility of resveratrol for the management of select hematological malignancies. In addition, potential clinical trials with resveratrol are suggested.

The Effect of Resveratrol on Cell Viability in the Burkitt's Lymphoma Cell Line Ramos

Resveratrol is a polyphenolic natural compound produced by a variety of crops. Currently, resveratrol is considered a multi-target anti-cancer agent with pleiotropic activity, including the ability to prevent the proliferation of malignant cells by inhibiting angiogenesis and curtailing invasive and metastatic factors in many cancer models. However, the molecular mechanisms mediating resveratrol-specific effects on lymphoma cells remain unknown. To begin tackling this question, we treated the Burkitt's lymphoma cell line Ramos with resveratrol and assessed cell survival and gene expression. Our results suggest that resveratrol shows a significant anti-proliferative and pro-apoptotic activity on Ramos cells, inducing the DNA damage response, DNA repairing, and modulating the expression of several genes that regulate the apoptotic process and their proliferative activity.

GENOCOP Algorithm and Hierarchical Grid Transformation for Image Warping of Two-Dimensional Gel Electrophoretic Maps

Hierarchical grid transformation is a powerful hierarchical approach to 2-D map warping, able to model both global and local deformations. The algorithm can be stopped when a desired degree of accuracy in the images alignment is obtained. The deformed image is warped and aligned to the target image using a grid where the number of nodes increases in each step of the algorithm. The numerical optimization of the position of the nodes of the grid can be efficiently solved by genetic algorithms, ensuring the achievement of the optimal position of the nodes with a low computational cost with respect to other methods. Here, the optimization of the position of the nodes is carried out by GENOCOP (genetic algorithm for numerical optimization of constrained problems), refined by the following conjugate gradient optimization step. The modeling of the warped space is then achieved by a spline model where some constraints are introduced in the choice of the nodes that are moved. The whole procedure can be intended as an evolutionary method that models the deformation of the gel map at different levels of detail.

Development and characterization of a Mantle Cell Lymphoma Cell Bank in the American Type Culture Collection

Mantle cell lymphoma (MCL) is a rare B-cell malignancy that carries a relatively poor prognosis compared to other forms of non-Hodgkin lymphoma. Standardized preclinical tools are desperately required to hasten the discovery and translation of promising new treatments for MCL. Via an initiative organized through the Mantle Cell Lymphoma Consortium and the Lymphoma Research Foundation, we gathered MCL cell lines from laboratories around the world to create a characterized MCL Cell Bank at the American Type Culture Collection (ATCC). Initiated in 2006, this collection now contains eight cell lines, all of which have been rigorously characterized and are now stored and available for distribution to the general scientific community. We believe the awareness and use of these standardized cell lines will decrease variability between investigators, harmonize international research efforts, improve our understanding of the pathogenesis of the disease and hasten the development of novel treatment strategies.

Opportunities and challenges for nutritional proteomics in cancer prevention

Knowledge gaps persist about the efficacy of cancer prevention strategies based on dietary food components. Adaptations to nutrient supply are executed through tuning of multiple protein networks that include transcription factors, histones, modifying enzymes, translation factors, membrane and nuclear receptors, and secreted proteins. However, the simultaneous quantitative and qualitative measurement of all proteins that regulate cancer processes is not practical using traditional protein methodologies. Proteomics offers an attractive opportunity to fill this knowledge gap and unravel the effects of dietary components on protein networks that impinge on cancer. The articles presented in this supplement are from talks proffered in the "Nutrition Proteomics and Cancer Prevention" session at the American Institute for Cancer Research Annual Research Conference on Food, Nutrition, Physical Activity and Cancer held in Washington, DC on October 21 and 22, 2010. Recent advances in MS technologies suggest that studies in nutrition and cancer prevention may benefit from the adoption of proteomic tools to elucidate the impact on biological processes that govern the transition from normal to malignant phenotype; to identify protein changes that determine both positive and negative responses to food components; to assess how protein networks mediate dose-, time-, and tissue-dependent responses to food components; and, finally, for predicting responders and nonresponders. However, both the limited accessibility to proteomic technologies and research funding appear to be hampering the routine adoption of proteomic tools in nutrition and cancer prevention research.

GENOCOP algorithm and hierarchical grid transformation for image warping of two dimensional gel eletrophoretic maps

Hierarchical grid transformation is a powerful approach to SDS 2DPAGE maps warping. The hierarchy of the warping transformation is able to model both global and local deformations of the gels and the algorithm can be stopped when a certain degree of accuracy in the image alignment is obtained. The numerical optimization of the position of the nodes of the grid that are responsible for the image warping is a multivariate task that can be solved efficiently using Genetic Algorithms. The use of Genetic Algorithms ensures that an optimal position of the nodes can be defined with a low computational cost with respect to other methods. The optimal positions of the nodes of the grid can be successfully used for defining a good warping of the gels.

Polar electrophoresis: shape of two-dimensional maps is as important as size

The performance of two-dimensional electrophoresis in conventional gels in Cartesian coordinates (2-DE) vs. polar coordinates (2-PE) is here evaluated. Although 2-DE is performed in much longer Immobiline gels in the first dimension (17 cm) vs. barely 7-cm in 2-PE, an equivalent resolving power is found. Moreover, due to the possibility of running up to seven Immobiline strips in the radial gel format, the reproducibility of spot position is seen to be higher, this resulting in a 20% higher matching efficiency. As an extra bonus, strings of “isobaric” spots (i.e. polypeptides of identical mass with different pI values) are more resolved in the radial gel format, especially in the 10 to 30 kDa region, where the gel area fans out leaving extra space for spot resolution. In conclusion, this novel gel format in the second dimension of 2D gels is seen as an important improvement of this technique, still one of the most popular in proteome analysis.

Resveratrol enhances the cytotoxic profile of docetaxel and doxorubicin in solid tumour cell lines in vitro

OBJECTIVES

  Resveratrol, with its robust antioxidant activity, has frequently been suggested as potentially having activity in cancer prevention and some recent reports have indicated that it has cancer treatment potential for several types of neoplasia. It has been found to block p-glycoprotein and to protect against several chemotherapeutic agents' side effects. In this study, we assessed interactive characteristics of resveratrol with docetaxel and doxorubicin and further investigated molecular bases of this interaction in cells of three different solid tumour lines (MCF-7, HeLa and HepG2).

MATERIALS AND METHODS AND RESULTS

  Resveratrol per se was found to have anti-cancer properties, but with relatively low potency in all tested cell lines (IC(50) ranged from 35.1 to 83.8 μM). Doxorubicin and docetaxel showed IC(50) ranging from 0.48 to 0.72 μM and from 25.9 to 77.8 nM, respectively. Resveratrol in combination with doxorubicin and docetaxel significantly increased potencies of both chemotherapeutic agents showing IC(50) ranging from 0.12 to 0.34 μM and from 7.2 to 53.02 nM, respectively. The combination index showed synergistic interaction between resveratrol and doxorubicin or docetaxel on MCF-7 cells, and additive interactions on HeLa and HepG2 cells. Real time PCR revealed that expression of Bax and Bcl-2 was simultaneously elevated on combination of resveratrol with doxorubicin or docetaxel in all tested cell lines, whereas p53 exhibited marginal elevation in MCF-7 and HepG2 cells. In addition, p-glycoprotein efflux activity was significantly inhibited, with subsequent accumulation of p-glycoprotein substrate in intracellular compartments. Expression level of mdr1 gene was downregulated after resveratrol combined with doxorubicin or docetaxel in all tested cell lines.

CONCLUSION

  Resveratrol potentiates cytotoxic properties of both cancer drugs used in the study through increasing their intracellular level due to p-glycoprotein inhibition and downregulation of mdr1 gene.

Phospho-proteomic analysis of mantle cell lymphoma cells suggests a pro-survival role of B-cell receptor signaling

Background

Mantle cell lymphoma (MCL) is currently an incurable entity, and new therapeutic approaches are needed. We have applied a high-throughput phospho-proteomic technique to MCL cell lines to identify activated pathways and we have then validated our data in both cell lines and tumor tissues.

Methods

PhosphoScan analysis was performed on MCL cell lines. Results were validated by flow cytometry and western blotting. Functional validation was performed by blocking the most active pathway in MCL cell lines.

Results

PhosphoScan identified more than 300 tyrosine-phosporylated proteins, among which many protein kinases. The most abundant peptides belonged to proteins connected with B-cell receptor (BCR) signaling. Active BCR signaling was demonstrated by flow cytometry in MCL cells and by western blotting in MCL tumor tissues. Blocking BCR signaling by Syk inhibitor piceatannol induced dose/time-dependent apoptosis in MCL cell lines, as well as several modifications in the phosphorylation status of BCR pathway members and a collapse of cyclin D1 protein levels.

Conclusion

Our data support a pro-survival role of BCR signaling in MCL and suggest that this pathway might be a candidate for therapy. Our findings also suggest that Syk activation patterns might be different in MCL compared to other lymphoma subtypes.

Electronic supplementary material

The online version of this article (doi:10.1007/s13402-011-0019-7) contains supplementary material, which is available to authorized users.

Analysis of NF-kappaB signaling pathways by proteomic approaches

NF-kappaB is a transcription factor that plays important roles in the regulation of apoptosis and inflammation as well as innate and adaptive immunity. Consequently, dysregulations in the NF-kappaB activation cascade have been associated with the pathogenesis of several diseases such as cancer, atherosclerosis and rheumatoid arthritis. Although NF-kappaB signaling pathways have been extensively investigated in this context, its varying components and targets are far from being completely elucidated. There is still an urgent need for the detection of novel NF-kappaB target proteins, novel interaction partners and novel regulators in the activation cascade, in particular with regard to its role in the aforementioned diseases. Therefore, several groups have performed different proteomic approaches to further investigate NF-kappaB signal transduction pathways. Most of these studies have been carried out in the area of cancer research; however, there are also several analyses in the field of inflammatory or autoimmune diseases. Furthermore, there have been a number of basic investigations that principally examined binding partners or so far unknown target proteins of NF-kappaB-related proteins. With these approaches, a number of novel and interesting proteins have been found that interfere with NF-kappaB signal transduction and might have an impact on NF-kappaB-related diseases. The results of these studies are summarized and discussed in this review.

Protein nitration during defense response in Arabidopsis thaliana

Nitric oxide and reactive oxygen species play a key role in the plant hypersensitive disease resistance response, and protein tyrosine nitration is emerging as an important mechanism of their co-operative interaction. Up to now, the proteins targeted by this post-translational modification in plants are still totally unknown. In this study, we analyzed for the first time proteins undergoing nitration during the hypersensitive response by analyzing via 1D- and 2D-western blot the protein extracts from Arabidopsis thaliana plants challenged with an avirulent bacterial pathogen (Pseudomonas syringae pv. Tomato). We show that the plant disease resistance response is correlated with a modulation of nitration of proteins involved in important cellular process, such as photosynthesis, glycolysis and nitrate assimilation. These findings shed new light on the signaling functions of nitric oxide and reactive oxygen species, paving the way on studies on the role of this post-translational modification in plants.