Arsenic trioxide induces cell cycle arrest and affects Trk receptor expression in human neuroblastoma SK-N-SH cells

BACKGROUND: Arsenic trioxide (As2O3), a drug that has been used in China for approximately two thousand years, induces cell death in a variety of cancer cell types, including neuroblastoma (NB). The tyrosine kinase receptor (Trk) family comprises three members, namely TrkA, TrkB and TrkC. Various studies have confirmed that TrkA and TrkC expression is associated with a good prognosis in NB, while TrkB overexpression can lead to tumor cell growth and invasive metastasis. Previous studies have shown that As2O3 can inhibit the growth and proliferation of a human NB cell line and can also affect the N-Myc mRNA expression. It remains unclear whether As2O3 regulates Trks for the purposes of treating NB. METHODS: The aim of the present study was to investigate the effect of As2O3 on Trk expression in NB cell lines and its potential therapeutic efficacy. SK-N-SH cells were grown with increasing doses of As2O3 at different time points. We cultured SK-N-SH cells, which were treated with increasing doses of As2O3 at different time points. Trk expression in the NB samples was quantified by immunohistochemistry, and the cell cycle was analyzed by flow cytometry. TrkA, TrkB and TrkC mRNA expression was evaluated by real-time PCR analysis. RESULTS: Immunohistochemical and real-time PCR analyses indicated that TrkA and TrkC were over-expressed in NB, and specifically during stages 1, 2 and 4S of the disease progression. TrkB expression was increased in stage 3 and 4 NB. As2O3significantly arrested SK-N-SH cells in the G2/M phase. In addition, TrkA, TrkB and TrkC expression levels were significantly upregulated by higher concentrations of As2O3 treatment, notably in the 48-h treatment period. Our findings suggested that to achieve the maximum effect and appropriate regulation of Trk expression in NB stages 1, 2 and 4S, As2O3 treatment should be at relatively higher concentrations for longer delivery times;however, for NB stages 3 and 4, an appropriate concentration and infusion time for As2O3 must be carefully determined. CONCLUSION: The present findings suggested that As2O3 induced Trk expression in SK-N-SH cells to varying degrees and may be a promising adjuvant to current treatments for NB due to its apoptotic effects.

Properties of realgar bioleaching using an extremely acidophilic bacterium and its antitumor mechanism as an anticancer agent

Realgar is a naturally occurring arsenic sulfide (or Xionghuang, in Chinese). It contains over 90% tetra-arsenic tetrasulfide (As4S4). Currently, realgar has been confirmed the antitumor activities, both in vitro and in vivo, of realgar extracted using Acidithiobacillus ferrooxidans (A. ferrooxidans). Bioleaching, a new technology to greatly improve the use rate of arsenic extraction from realgar using bacteria, is a novel methodology that addressed a limitation of the traditional method for realgar preparation. The present systematic review reports on the research progress in realgar bioleaching and its antitumor mechanism as an anticancer agent. A total of 93 research articles that report on the biological activity of extracts from realgar using bacteria and its preparation were presented in this review. The realgar bioleaching solution (RBS) works by inducing apoptosis when it is used to treat tumor cells in vitro and in vivo. When it is used to treat animal model organisms in vivo, such as mice and Caenorhabditis elegans, tumor tissues grew more slowly, with mass necrosis. Meanwhile, the agent also showed obvious inhibition of tumor cell growth. Bioleaching technology greatly improves the utilization of realgar and is a novel methodology to improve the traditional method.

Recovery: revisão sistemática de um conceito / Recovery: systematic review of a concept

O conceito de recovery tem sido descrito em artigos como um estado de recuperação ou restabelecimento de funções psíquicas, físicas e sociais no funcionamento cotidiano. O objetivo do artigo é analisar concepções terminológicas em diferentes metodologias investigativas e a evolução paradigmática da noção de recovery. Pesquisa bibliográfica sistemática na base Pubmed com as palavras "recovery + schizophrenia", limitada a dois anos retrospectivos e a artigos completos gratuitos. Dezenove artigos foram analisados. A maioria destes busca associações entre dada característica e recovery, poucos são aqueles que discutem a sua concepção de forma que se distinga de termos comuns como "cura" e "reabilitação". Recovery como um estado em que o portador de transtorno mental grave possa sentir-se criador de seus caminhos tende a estar presente em estudos com metodologia qualitativa e em revisões bibliográficas, em que a medida de recovery deixa de relacionar-se à ausência de sintomas e passa a priorizar o quão participativa pode ser a vida de um indivíduo apesar da doença. Alguns estudos quantitativos vislumbram essa diferença conceitual. Em pesquisas qualitativas ocorre expansão na concepção de recovery e nas formas de promovê-lo.

The concept of recovery has been described in papers as a state of psychic, physical and social recuperation of day-to-day functions. The scope of this article is to analyze the concepts of the term in different research methodologies and the paradigmatic evolution of the recovery concept. Systematic bibliographical research was conducted in the Pubmed database using the words "recovery + schizophrenia" limited to freely available full papers published in the previous two years. Nineteen papers were analyzed. The majority of the papers sought associations between characteristic data and recovery; few papers discussed the concept in a way to distinguish it from other words like cure or rehabilitation. Recovery as a state in which people with severe mental illness can feel like the creators of their own itinerary tend to be found in qualitative studies and in bibliographic reviews in which the meaning of recovery is not related to the lack of symptoms and tends to prioritize how participative the life of an individual can be despite the disease. Some quantitative studies detect this conceptual difference. In qualitative research there is an increase in the concept of recovery and in ways of promoting it.

Autocuidado do cuidador familiar de adultos ou idosos dependentes após a alta hospitalar / Self-care in family caregiver of dependent adults or elderly persons after hospital discharge / El autocuidado del cuidador familiar de adultos o ancianos dependientes tras el alta hospitalaria

Este artigo apresenta uma compreensão sobre o autocuidado do cuidador familiar segundo a teoria de Dorothea Orem. Resulta de uma pesquisa qualitativa com aporte da Teoria Fundamentada nos Dados, utilizando-se das técnicas de visita domiciliar, registro de notas de campo e entrevista semiestruturada com 11 cuidadores, após a internação de familiar em um Hospital Universitário de Minas Gerais. Foram obtidas quatro categorias, destacando uma categoria central, em torno da qual se analisaram as facilidades, dificuldades e estratégias para o autocuidado do cuidador. Entre as dificuldades, foram evidenciadas: tempo insuficiente para os cuidados com a saúde e, entre as facilidades, o apoio de outros familiares. As principais estratégias foram: apoio na fé; revezamento nos cuidados e recursos na comunidade. Concluiu-se que orientações no momento da alta e o acompanhamento de enfermagem após a alta contribuem para o autocuidado do cuidador, atuando sobre suas dificuldades e estimulando suas potencialidades.

This article presents an understanding concerning self-care in family caregivers according to Dorothea Orem's theory. Resulting from a qualitative research based on Grounded Theory, this work uses the techniques of home visiting, field notes and semistructured interviews with 11 caregivers after the hospitalization of a family member in a teaching Hospital located in Minas Gerais. Four categories were found and among them a central category is highlighted from which some facilities, difficulties and strategies for selfcare in caregiver were analyzed. Considering the difficulties, insufficient time for healthcare was noticed whereas the support from other family members appeared as a facility. The main strategies were: faith as a support; shift work in healthcare and community resources. This study demonstrated that hospital discharge guidelines and nursing follow-up after discharge were responsible for positive contributions to self-care in caregivers helping them to overcome their difficulties and enhancing their potentialities.

El artículo presenta una comprensión sobre el autocuidado del cuidador familiar, según la teoría de Dorothea Orem. Resulta de investigación cualitativa con aporte de la Teoría Fundamentada en los Datos, utilizándo se de las técnicas de visitas a domicilio; registro de apuntes de campo y entrevista semiestructurada, tras la internación de un familiar en un hospital universitario de Minas Gerais. Se llegó a cuatro categorías, señalando una categoría central, alrededor de la cual se analizaron las facilidades, dificultades y estrategias para el autocuidado del cuidador. Se evidenció, entre las dificultades, tiempo insuficiente para los cuidados con la salud y, entre las facilidades, el apoyo de otros familiares. Las principales estrategias fueron: apoyo en la fe, revezo en los cuidados y recursos en la comunidad. Se concluyó que orientaciones el momento del alta y el acompañamiento de enfermería tras el alta contribuyen para el autocuidado del cuidador, actuando sobre sus dificultades y estimulando sus potencialidades.

Tetramethylpyrazine potentiates arsenic trioxide activity against HL-60 cell lines

The objective of this study was to evaluate the effects of tetramethylpyrazine (TMP) in combination with arsenic trioxide (As2O3) on the proliferation and differentiation of HL-60 cells. The HL-60 cells were treated with 300 µg/mL TMP, 0.5 µM As2O3, and 300 µg/mL TMP combined with 0.5 µM As2O3, respectively. The proliferative inhibition rates were determined with MTT. Differentiation was detected by the nitroblue tetrazolium (NBT) reduction test, Wright’s staining and the distribution of CD11b and CD14. Flow cytometry was used to analyze cell cycle distribution. RT-PCR and Western blot assays were employed to detect the expressions of c-myc, p27, CDK2, and cyclin E1. Combination treatment had synergistic effects on the proliferative inhibition rates. The rates were increased gradually after the combination treatment, much higher than those treated with the corresponding concentration of As2O3 alone. The cells exhibited characteristics of mature granulocytes and a higher NBT-reducing ability, being a 2.6-fold increase in the rate of NBT-positive ratio of HL-60 cells within the As2O3 treatment versus almost a 13-fold increase in the TMP + As2O3 group. Cells treated with both TMP and As2O3 expressed far more CD11b antigens, almost 2-fold compared with the control group. Small doses of TMP potentiate As2O3-induced differentiation of HL-60 cells, possibly by regulating the expression and activity of G0/G1 phase-arresting molecules. Combination treatment of TMP with As2O3 has significant synergistic effects on the proliferative inhibition of HL-60 cells.

Effects of Arsenic Trioxide on Radiofrequency Ablation of VX2 Liver Tumor: Intraarterial versus Intravenous Administration

OBJECTIVE: Arsenic trioxide (As2O3) can be used as a possible pharmaceutical alternative that augments radiofrequency (RF) ablation by reducing tumor blood flow. The aim of this study was to assess the effect of intraarterial and intravenous administration of As2O3 on RF-induced ablation in an experimentally induced liver tumor. MATERIALS AND METHODS: VX2 carcinoma was grown in the livers of 30 rabbits. As2O3 (1 mg/kg) was administered through the hepatic artery (n = 10, group A) or ear vein (n = 10, group B), 30 minutes before RF ablation (125 mA +/- 35; 90 +/- 5degrees C). As a control group, 10 rabbits were treated with RF ablation alone (group C). RF was intentionally applied to the peripheral margin of the tumor so that ablation can cover the tumor and adjacent hepatic parenchyma. Ablation areas of the tumor and adjacent parenchymal changes among three groups were compared by the Kruskal-Wallis and Mann-Whitney U test. RESULTS: The overall ablation areas were 156 +/- 28.9 mm2 (group A), 119 +/- 31.7 (group B), and 92 +/- 17.4 (group C, p < 0.04). The ablation area of the tumor was significantly larger in group A (73 +/- 19.7 mm2) than both group B (50 +/- 19.4, p = 0.02) and group C (28 +/- 2.2, p < 0.01). The ratios of the tumoral ablation area to the overall ablation area were larger in group A (47 +/- 10.5%) than that of the other groups (42 +/- 7.3% in group B and 32 +/- 5.6% in group C) (p < 0.03). CONCLUSION: Radiofrequency-induced ablation area can be increased with intraarterial or intravenous administration of As2O3. The intraarterial administration of As2O3 seems to be helpful for the selective ablation of the tumor.

E3 ubiquitin ligase Cbl-b potentiates the apoptotic action of arsenic trioxide by inhibiting the PI3K/Akt pathway

Arsenic trioxide (ATO) is a strong inducer of apoptosis in malignant hematological cells. Inducible phosphatidyl inositol 3 kinase (PI3K)-Akt activation promotes resistance to ATO. In the present study, we evaluated whether E3 ubiquitin ligase Cbl-b, a negative regulator of PI3K activation, is involved in the action of ATO. The effect of ATO on cell viability was measured by the Trypan blue exclusion assay or by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Apoptosis was determined by flow cytometry and protein expression was assayed by Western blotting. ATO decreased the viability of HL60 cells and induced cellular apoptosis, which was accompanied by transient activation of Akt. The PI3K/Akt inhibitor, LY294002, significantly increased ATO-induced apoptosis (P < 0.05). In addition, ATO up-regulated the expression of Cbl-b proteins. Furthermore, ATO inhibited cell viability with an IC50 of 18.54 μM at 24 h in rat basophilic leukemia-2H3 cells. ATO induced cellular apoptosis with transient activation of Akt and Cbl-b was also up-regulated. Rat basophilic leukemia-2H3 cells transfected with a dominant negative (DN) Cbl-b mutation showed overexpression of Cbl-b (DN) and enhanced Akt activation. Compared with cells transfected with vector, ATO-induced apoptosis was decreased and G2/M phase cells were increased at the same concentration (P < 0.05). The PI3K/Akt inhibitor, LY294002, re-sensitized Cbl-b (DN) overexpressing cells to ATO and reversed G2/M arrest (P < 0.05). Taken together, these results suggest that Cbl-b potentiates the apoptotic action of ATO by inhibition of the PI3K/Akt pathway.

Gene expression profile of multiple myeloma cell line treated by arsenic trioxide / 华中科技大学学报（医学）（英德文版）

cDNA microarray was used to compare the gene expression profiles of multiple myeloma cell line RPMI8226 24 h before and after treatment with arsenic trioxide. Two cDNA probes were prepared by mRNA reverse transcription of both arsenic trioxide-treated and untreated RPMI8226 cells. The probes were labeled with Cy3 and Cy5 fluorescence dyes separately, hybridized with cDNA microarray representing 4096 different human genes, and scanned for fluorescence intensity. The differences in gene expression were calculated on the basis of the ratios of signal intensity of treated and untreated samples. The up-and down-regulated genes were screened through the analysis of gene expression ratios. The results showed that 273 genes were differentially altered at mRNA level, 121 genes were up-regulated and 152 were down-regulated. It is concluded that the treatment with arsenic trioxide can induce a variety of gene changes in RPMI8226 cell line. Many genes may be involved in the pathogenesis of multiple myeloma. ALK-1 and TXNIP genes may play an important role in the apoptosis and partial differentiation of RPMI8226 cells.

Arsenic trioxide reduces the invasive and metastatic properties of nasopharyngeal carcinoma cells in vitro

Nasopharyngeal carcinoma (NPC) is notorious for the metastases, which are in close association with Epstein-Barr virus-encoded latent membrane protein 1 (LMP1). Arsenic trioxide (As2O3) has been shown to induce apoptosis and differentiation in NPC xenografts. Then, can it repress the cancer cells' metastasis potential? To elucidate this issue, the present study was performed. LMP1-negative cell line HNE1 and LMP1-positive cell line HNE1-LMP1 were used as in vitro model. Cells (1 x 10(5)/mL) were cultured with or without 3 æM As2O3 for 48 h. Then the survival cells were collected to investigate their potential of colony formation, attachment, invasion, and migration. Both confocal immunofluorescence staining and Western blot were used to detect the changes of LMP1 expression. The changes of MMP-9 were examined by RT-PCR assay and Western blot. The results were as follow: i) the colony formation inhibition rate (75.41 ± 3.9 percent in HNE1-LMP1 cells vs 37.89 ± 4.9 percent in HNE1 cells), the rate of attachment (HNE1-LMP1 vs HNE1: 56.40 ± 3.5 vs 65.87 ± 5.9 percent), the invasion inhibitory rate (HNE1-LMP1 vs HNE1: 56.50 ± 3.7 and 27.91 ± 2.1 percent), and the migration inhibitory rate (HNE1-LMP1 vs HNE1: 48.70 ± 3.9 vs 29.19 ± 6.27 percent) were all significantly different between the two cell lines (P < 0.01). ii) LMP1 was down-regulated in As2O3-treated HNE1-LMP1 cells. iii) The reduction of MMP-9 was found in As2O3-treated groups, more evident in HNE1-LMP1 cells. Thus, we conclude that As2O3 can reduce metastasis potential of NPC cells, involving inhibition of MMP-9 expression. LMP1 were also reduced in this process and seemed to enhance anti-metastasis activity of As2O3.

Functional involvement of src and focal adhesion kinase in a CD99 splice variant-induced motility of human breast cancer cells

Earlier report showed that expression of a splice variant of CD99 transmembrane protein increases invasive ability of human breast cancer cells. Cell motility was also significantly enhanced by the CD99 splice variant expression. In an effort to identify the cellular components that mediate a signal transduction pathway triggered by the CD99 splice variant, known signal path inhibitors were examined for their effects on the motility of the CD99 splice variant-transfected MDA-MB-231 breast cancer cells. Phenylarsine oxide, an inhibitor of phosphatase specific for focal adhesion kinase, and PP1, an inhibitor of src kinase family, significantly suppressed motility of the cells. Among different types of src transfectant clones generated, kinase-negative mutant src transfectant cells were 80% less motile than the mock cells transfected with an empty-vector, while v-src and c-src transfectants exhibited cell motility levels at or slightly above the mock transfectant. These results suggest that src and focal adhesion kinase mediate the intracellular signaling pathway of a CD99 splice variant for the induction of motility of human breast cancer cells.

Anti-nematode activity of sixteen compounds against Trichinella spiralis in mice--a possible new screen for macrofilaricides.

There are few small animals models for filariasis, even more so for onchocerciasis. Therefore it is difficult to test under drug screening conditions large numbers of potentially macrofilaricidal compounds. One way around this difficulty is to use mice infected with Trichinella spiralis which by reason of anatomical location in the host would show some correlation in antinematode activity between the test and target organisms. This study investigated the activity of 16 compounds against the immature larval stage of T. spiralis. All the nine benzimidazole compounds (albendazole, flubendazole, mebendazole, oxfendazole, oxibendazole 780118, 780120, 790163, and 790392) were active, the most potent being oxfendazole. The benzothiazoles (CGP21306, CGP20376, CGP21833 and CGP24588A) also indicated some anti-nematode activity together with 35vr, an imidazopyridine, but not as marked as the benzimidazole group. However, the organic arsenical compounds (Mel Ga and Mel Ni) showed little activity and this was at a rather highly toxic level. The prospects of using the Trichinella-mouse model as a primary screen to test for potential macrofilaricides are discussed.