A novel DNA intercalator, 8-methoxy pyrimido4 `,5 `:4,5]thieno (2,3-b)quinoline-4(3H)-one induces apoptosis in cancer cells, inhibits the tumor progression and enhances lifespan in mice with tumor

Polycyclic aromatic molecules such as ellipticine intercalate into double-stranded DNA and interfere with physiological functions. In the present study, we evaluate the chemotherapeutic potential of MPTQ on animal models and its mode of action. In order to test the antitumor activity, monohydrochloride of MPTQ was orally administered in mice bearing tumor. Results showed a significant inhibition of tumor growth compared to that of untreated controls. More importantly, mean lifespan of tumor bearing animals treated with MPTQ was significantly higher as compared to that of untreated tumor bearing mice suggesting that the treatment affected viability of cancerous cells, but not of normal cells. Consistent with this, we find that administration of MPTQ to normal mice did not cause any major side effects as observed upon hematological and serum profiling. We also found that MPTQ induces cytotoxicity in cancer cell lines, by activating apoptosis both by intrinsic and extrinsic pathways. Thus, MPTQ could be used as a potential cancer therapeutic agent. (c) 2011 Wiley Periodicals, Inc.

Antiangiogenic VEGF-Ax: A New Participant in Tumor Angiogenesis

The transcript of the angiogenic factor vascular endothelial growth factor A (VEGF-A) is subject to a multitude of stimulus-dependent, posttranscriptional regulatory events, consistent with its unusually long 30 untranslated region. We have recently reported translational readthrough of VEGFA mRNA whereby translating ribosomes traverse the canonical stop codon to a conserved, downstream stop codon, generating VEGF-Ax (''x'' for extended), a novel, extended isoform with an additional 22 amino acids appended at the C-terminus. This event is the first vertebrate example of protein-regulated, programmed translational readthrough that generates a protein with a known function. Remarkably, VEGF-Ax exhibits potent antiangiogenic activity, both in vitro and in vivo, thus raising profound clinical implications, particularly with respect to cancer treatment. In this review, we discuss the potential of VEGF-Ax as a therapeutic agent and drug target, as well as its possible role in the failure of, or resistance to, conventional anti-VEGF therapies in many types of cancers. (C) 2015 AACR.

Antiproliferative and tumor inhibitory studies of 2,3 disubstituted 4-thiazolidinone derivatives

4-Thiazolidinone derivatives were synthesized using T3P (R)-DMSO media as a cyclodehydrating agent. All the molecules were tested for their cytotoxicity against leukemic cell lines. The compound 3-(4-bromophenyl)-2-(4-(dimethylamino)phenyl)thiazolidin-4-one (4e) with electron donating substituent at para position of phenyl ring displayed considerable cytotoxicity against Reh and Nalm6 cells with an IC50 value of 11.9 and 13.5 mu M, respectively. Furthermore, the compound 4e tested for tumor regression studies induced by EAC in Swiss albino mouse. Both in vitro and in vivo results suggested significant antiproliferative activity of compound 4e in Reh cells and mouse tumor tissue treated with compound 4e showed multifocal areas of necrosis and numerous number of apoptotic cells. (C) 2015 Elsevier Ltd. All rights reserved.

Inhibition of p300 lysine acetyltransferase activity by luteolin reduces tumor growth in head and neck squamous cell carcinoma (HNSCC) xenograft mouse model

Chromatin acetylation is attributed with distinct functional relevance with respect to gene expression in normal and diseased conditions thereby leading to a topical interest in the concept of epigenetic modulators and therapy. We report here the identification and characterization of the acetylation inhibitory potential of an important dietary flavonoid, luteolin. Luteolin was found to inhibit p300 acetyltransferase with competitive binding to the acetyl CoA binding site. Luteolin treatment in a xenografted tumor model of head and neck squamous cell carcinoma (HNSCC), led to a dramatic reduction in tumor growth within 4 weeks corresponding to a decrease in histone acetylation. Cells treated with luteolin exhibit cell cycle arrest and decreased cell migration. Luteolin treatment led to an alteration in gene expression and miRNA profile including up-regulation of p53 induced miR-195/215, let7C; potentially translating into a tumor suppressor function. It also led to down regulation of oncomiRNAs such as miR-135a, thereby reflecting global changes in the microRNA network. Furthermore, a direct correlation between the inhibition of histone acetylation and gene expression was established using chromatin immunoprecipitation on promoters of differentially expressed genes. A network of dysregulated genes and miRNAs was mapped along with the gene ontology categories, and the effects of luteolin were observed to be potentially at multiple levels: at the level of gene expression, miRNA expression and miRNA processing.

Extract of Vernonia condensata, Inhibits Tumor Progression and Improves Survival of Tumor-allograft Bearing Mouse

Medicinal plants are considered as one of the ideal sources for cancer therapy due to their bioactive contents and low toxicity to humans. Vernonia genus is one of the common medicinal plants, which has wide spread usage in food and medicine. However, there are limited studies to explore its anticancer properties. In the current study, we have used Vernonia condensata, to explore its anticancer activity using various approaches. Here, we show that extract prepared from Vernonia condensata (VCE) exhibits cytotoxic properties against various cancer cells in a dose- and time-dependent manner. Interestingly, when treated with VCE, there was no significant cytotoxicity in peripheral blood mononuclear cells (PBMCs). Flow cytometry analysis revealed that although VCE induced cell death, arrest was not observed. VCE treatment led to disruption of mitochondrial membrane potential in a concentration dependent manner resulting in activation of apoptosis culminating in cell death. Immunoblotting studies revealed that VCE activated intrinsic pathway of apoptosis. More importantly, VCE treatment resulted in tumor regression leading to significant enhancement in life span in treated mice, without showing any detectable side effects. Therefore, for the first time our study reveals the potential of extract from Vernonia condensata to be used as an anticancer agent.

Quercetin, a Natural Flavonoid Interacts with DNA, Arrests Cell Cycle and Causes Tumor Regression by Activating Mitochondrial Pathway of Apoptosis

Naturally occurring compounds are considered as attractive candidates for cancer treatment and prevention. Quercetin and ellagic acid are naturally occurring flavonoids abundantly seen in several fruits and vegetables. In the present study, we evaluate and compare antitumor efficacies of quercetin and ellagic acid in animal models and cancer cell lines in a comprehensive manner. We found that quercetin induced cytotoxicity in leukemic cells in a dose-dependent manner, while ellagic acid showed only limited toxicity. Besides leukemic cells, quercetin also induced cytotoxicity in breast cancer cells, however, its effect on normal cells was limited or none. Further, quercetin caused S phase arrest during cell cycle progression in tested cancer cells. Quercetin induced tumor regression in mice at a concentration 3-fold lower than ellagic acid. Importantly, administration of quercetin lead to -5 fold increase in the life span in tumor bearing mice compared to that of untreated controls. Further, we found that quercetin interacts with DNA directly, and could be one of the mechanisms for inducing apoptosis in both, cancer cell lines and tumor tissues by activating the intrinsic pathway. Thus, our data suggests that quercetin can be further explored for its potential to be used in cancer therapeutics and combination therapy.

Evaluacion de la efectividad de dos metodos terapeuticos para el tratamiento del tumor de Sticker en caninos (Canis familiaris) durante el periodo de mayo a noviembre 2010

Con el objetivo de evaluar comparativamente los resultados de dos métodos de tratamiento (químico y quirúrgico), para eliminar el tumor de Sticker y conocer cual de los dos tratamientos es mas efectivo, se comparo la evolución post-tratamiento de los pacientes, estableciendo ventajas y desventajas de cada uno, además valorando los efectos colaterales de la aplicación de sulfato de vincristina, como compuesto químico, a través del seguimiento evolutivo del paciente y realización de exámenes complementarios (BHC), además de determinar los costos de aplicación y relacionarlos con la efectividad de los mismos, el estudio se llevó a cabo de Mayo a Noviembre del 2010, para ello se utilizaron 12 canes elegidos al azar, de diferentes edades, razas y sexo, previamente diagnosticados con el Tumor Venéreo Transmisible, estos se dividieron en 2 grupos de 6 pacientes cada uno; al primer grupo se le practicó cirugía para extirpar el tumor en el complejo universitario Tania Beteta y el segundo grupo se trato con quimioterapia, realizado en la Clínica Veterinaria Lupita en Granada, aplicando una dosis semanal para cada paciente en dependencia del peso, los datos se analizaron en el programa estadístico SAS, mediante análisis de varianza y separaciones de medias según Duncan, las variables evaluadas fueron recuperación, frecuencia respiratoria (FR), frecuencia cardiaca (FC), examen clínico y evolución del tumor, encontrándose diferencia altamente significativa entre tratamientos, siendo el mejor método el químico, se encontró también diferencia significativa en la FR, donde el método químico fue mejor, en cuanto a la FC no se encontró variación alguna, el tratamiento quirúrgico requirió más examen clínico, se encontró diferencia significativa en la evolución del tumor resultando más efectivo el método químico, se determinó que la evolución de los tratamientos estaban relacionados con el peso vivo de los animales, el costo total para el tratamiento químico fue de $75.58 y para el tratamiento quirúrgico de $ 69.11 con una diferencia de $ 6.48 en contra del tratamiento químico.

A Proteomic Study on Cell Cycle Progression of Endothelium Exposed to Tumor Conditioned Medium and the Possible Role of Cyclin D-1/E

This study was designed to comprehensively analyze the differential expression of proteins from human umbilical vein endothelial cells (HUVECs) exposed to tumor conditioned medium (TCM) and to identify the key regulator in the cell cycle progression. The HUVECs were exposed to TCM from breast carcinoma cell line MDA-MB-231, then their cell cycle distribution was measured by flow cytometer (FCM). The role of protein in cell cycle progression was detected via two-dimensional polyacrylamide gel electrophoresis (2-DE) and western blotting. Following the stimulation of TCM, HUVECs showed a more cells in the S phase than did the negative control group (ECGF-free medium with 20% FBS), but the HUVECs' level was similar to the positive control group (medium with 25 mug/ml ECGF and 20% FBS). Increased expression of cyclin D-1/E and some changes in other related proteins occurred after incubation with TCM. From our results, we can conclude that breast carcinoma cell line MDA-MB-231 may secrete soluble pro-angiogenic factors that induce the HUVEC angiogenic switch, during which the expression of cell cycle regulator cyclin D-1/E increases and related proteins play an important role in this process.

The Mitogenic and Anti-Apoptotic Activity of Tumor Conditioned Medium on Endothelium

This study was designed to observe the effect of tumor conditioned medium (TCM) on the proliferation and apoptosis of human umbilical vein endothelial cells (HUVECs). HUVECs were exposed to TCM from breast carcinoma cell line MDA-MB-231, then we measured their proliferation, apoptosis and cell cycle distribution by MTT and flow cytometery (FCM). Following the stimulation of TCM, HUVECs showed higher pro-mitogenic and anti-apoptotic ability than did the negative control group (ECGF-free medium with 20% FBS), but a similar ability to the positive control group (medium with ECGF and 20% FBS). From these results, we can conclude that breast carcinoma cell line MDA-MB-231 could secret soluble pro-angiogenic factors that induce HUVEC angiogenic switching, including cell cycle progression, proliferation and growth. The role and character of these factors remain to be further studied.

Candida albicans Increases Tumor Cell Adhesion to Endothelial Cells In Vitro: Intraspecific Differences and Importance of the Mannose Receptor

The dimorphic fungus Candida albicans is able to trigger a cytokine-mediated pro-inflammatory response that increases tumor cell adhesion to hepatic endothelium and metastasis. To check the intraspecific differences in this effect, we used an in vitro murine model of hepatic response against C. albicans, which made clear that tumor cells adhered more to endothelium incubated with blastoconidia, both live and killed, than germ tubes. This finding was related to the higher carbohydrate/protein ratio found in blastoconidia. In fact, destruction of mannose ligand residues on the cell surface by metaperiodate treatment significantly reduced tumor cell adhesion induced. Moreover, we also noticed that the effect of clinical strains was greater than that of the reference one. This finding could not be explained by the carbohydrate/protein data, but to explain these differences between strains, we analyzed the expression level of ten genes (ADH1, APE3, IDH2, ENO1, FBA1, ILV5, PDI1, PGK1, QCR2 and TUF1) that code for the proteins identified previously in a mannoprotein-enriched pro-metastatic fraction of C. albicans. The results corroborated that their expression was higher in clinical strains than the reference one. To confirm the importance of the mannoprotein fraction, we also demonstrate that blocking the mannose receptor decreases the effect of C. albicans and its mannoproteins, inhibiting IL-18 synthesis and tumor cell adhesion increase by around 60%. These findings could be the first step towards a new treatment for solid organ cancers based on the role of the mannose receptor in C. albicans-induced tumor progression and metastasis.

Vascular endothelial growth factor regulates melanoma cell adhesion and growth in the bone marrow microenvironment via tumor cyclooxygenase-2

Background: Human melanoma frequently colonizes bone marrow (BM) since its earliest stage of systemic dissemination, prior to clinical metastasis occurrence. However, how melanoma cell adhesion and proliferation mechanisms are regulated within bone marrow stromal cell (BMSC) microenvironment remain unclear. Consistent with the prometastatic role of inflammatory and angiogenic factors, several studies have reported elevated levels of cyclooxygenase-2 (COX-2) in melanoma although its pathogenic role in bone marrow melanoma metastasis is unknown. Methods: Herein we analyzed the effect of cyclooxygenase-2 (COX-2) inhibitor celecoxib in a model of generalized BM dissemination of left cardiac ventricle-injected B16 melanoma (B16M) cells into healthy and bacterial endotoxin lipopolysaccharide (LPS)-pretreated mice to induce inflammation. In addition, B16M and human A375 melanoma (A375M) cells were exposed to conditioned media from basal and LPS-treated primary cultured murine and human BMSCs, and the contribution of COX-2 to the adhesion and proliferation of melanoma cells was also studied. Results: Mice given one single intravenous injection of LPS 6 hour prior to cancer cells significantly increased B16M metastasis in BM compared to untreated mice; however, administration of oral celecoxib reduced BM metastasis incidence and volume in healthy mice, and almost completely abrogated LPS-dependent melanoma metastases. In vitro, untreated and LPS-treated murine and human BMSC-conditioned medium (CM) increased VCAM-1-dependent BMSC adherence and proliferation of B16M and A375M cells, respectively, as compared to basal medium-treated melanoma cells. Addition of celecoxib to both B16M and A375M cells abolished adhesion and proliferation increments induced by BMSC-CM. TNF alpha and VEGF secretion increased in the supernatant of LPS-treated BMSCs; however, anti-VEGF neutralizing antibodies added to B16M and A375M cells prior to LPS-treated BMSC-CM resulted in a complete abrogation of both adhesion-and proliferation-stimulating effect of BMSC on melanoma cells. Conversely, recombinant VEGF increased adherence to BMSC and proliferation of both B16M and A375M cells, compared to basal medium-treated cells, while addition of celecoxib neutralized VEGF effects on melanoma. Recombinant TNFa induced B16M production of VEGF via COX-2-dependent mechanism. Moreover, exogenous PGE2 also increased B16M cell adhesion to immobilized recombinant VCAM-1. Conclusions: We demonstrate the contribution of VEGF-induced tumor COX-2 to the regulation of adhesion-and proliferation-stimulating effects of TNFa, from endotoxin-activated bone marrow stromal cells, on VLA-4-expressing

Expression and activity profiles of DPP IV/CD26 and NEP/CD10 glycoproteins in the human renal cancer are tumor-type dependent

Background: Cell-surface glycoproteins play critical roles in cell-to-cell recognition, signal transduction and regulation, thus being crucial in cell proliferation and cancer etiogenesis and development. DPP IV and NEP are ubiquitous glycopeptidases closely linked to tumor pathogenesis and development, and they are used as markers in some cancers. In the present study, the activity and protein and mRNA expression of these glycoproteins were analysed in a subset of clear-cell (CCRCC) and chromophobe (ChRCC) renal cell carcinomas, and in renal oncocytomas (RO). Methods: Peptidase activities were measured by conventional enzymatic assays with fluorogen-derived substrates. Gene expression was quantitatively determined by qRT-PCR and membrane-bound protein expression and distribution analysis was performed by specific immunostaining. Results: The activity of both glycoproteins was sharply decreased in the three histological types of renal tumors. Protein and mRNA expression was strongly downregulated in tumors from distal nephron (ChRCC and RO). Moreover, soluble DPP IV activity positively correlated with the aggressiveness of CCRCCs (higher activities in high grade tumors). Conclusions: These results support the pivotal role for DPP IV and NEP in the malignant transformation pathways and point to these peptidases as potential diagnostic markers.

Microglia in the cerebral and cerebellar cortices in individuals with autism

In this thesis, we explore the density of the microglia in the cerebral and cerebellar cortices of individuals with autism to investigate the hypothesis that neuroinflammation is involved in autism. We describe in our findings an increase in microglial density in two disparate cortical regions, frontal insular cortex and visual cortex, in individuals with autism (Tetreault et al., 2012). Our results imply that there is a global increase in the microglial density and neuroinflammation in the cerebral cortex of individuals with autism.

We expanded our cerebellar study to additional neurodevelopmental disorders that exhibit similar behaviors to autism spectrum disorder and have known cerebellar pathology. We subsequently found a more than threefold increase in the microglial density specific to the molecular layer of the cerebellum, which is the region of the Purkinje and parallel fiber synapses, in individuals with autism and Rett syndrome. Moreover, we report that not only is there an increase in microglia density in the molecular layer, the microglial cell bodies are significantly larger in perimeter and area in individuals with autism spectrum disorder and Rett syndrome compared to controls that implies that the microglia are activated. Additionally, an individual with Angelman syndrome and the sibling of an individual with autism have microglial densities similar to the individuals with autism and Rett syndrome. By contrast, an individual with Joubert syndrome, which is a developmental hypoplasia of the cerebellar vermis, had a normal density of microglia, indicating the specific pathology in the cerebellum does not necessarily result in increased microglial densities. We found a significant decrease in Purkinje cells specific to the cerebellar vermis in individuals with autism.

These findings indicate the importance for investigation of the Purkinje synapses in autism and that the relationship between the microglia and the synapses is of great utility in understanding the pathology in autism. Together, these data provide further evidence for the neuroinflammation hypothesis in autism and a basis for future investigation of neuroinflammation in autism. In particular, investigating the function of microglia in modifying synaptic connectivity in the cerebellum may provide key insights into developing therapeutics in autism spectrum disorder.

Firing Patterns of Cerebellar Purkinje Cells During Locomotion and Sleep

The cerebellum is a major supraspinal center involved in the coordination of movement. The principal neurons of the cerebellar cortex, Purkinje cells, receive excitatory synaptic input from two sources: the parallel and climbing fibers. These pathways have markedly different effects: the parallel fibers control the rate of simple sodium spikes, while the climbing fibers induce characteristic complex spike bursts, which are accompanied by dendritic calcium transients and play a key role in regulating synaptic plasticity. While many studies using a variety of species, behaviors, and cerebellar regions have documented modulation in Purkinje cell activity during movement, few have attempted to record from these neurons in unrestrained rodents. In this dissertation, we use chronic, multi-tetrode recording in freely-behaving rats to study simple and complex spike firing patterns during locomotion and sleep. Purkinje cells discharge rhythmically during stepping, but this activity is highly variable across steps. We show that behavioral variables systematically influence the step-locked firing rate in a step-phase-dependent way, revealing a functional clustering of Purkinje cells. Furthermore, we find a pronounced disassociation between patterns of variability driven by the parallel and climbing fibers, as well as functional differences between cerebellar lobules. These results suggest that Purkinje cell activity not only represents step phase within each cycle, but is also shaped by behavior across steps, facilitating control of movement under dynamic conditions. During sleep, we observe an attenuation of both simple and complex spiking, relative to awake behavior. Although firing rates during slow wave sleep (SWS) and rapid eye movement sleep (REM) are similar, simple spike activity is highly regular in SWS, while REM is characterized by phasic increases and pauses in simple spiking. This phasic activity in REM is associated with pontine waves, which propagate into the cerebellar cortex and modulate both simple and complex spiking. Such a temporal coincidence between parallel and climbing fiber activity is known to drive plasticity at parallel fiber synapses; consequently, pontocerebellar waves may provide a mechanism for tuning synaptic weights in the cerebellum during active sleep.