rhBMP-2 induces terminal differentiation of human bone marrow mesenchymal stromal cells only by synergizing with other signals.

BACKGROUND: Recombinant human bone morphogenetic protein 2 (rhBMP-2) and human bone marrow mesenchymal stromal cells (hBM-MSCs) have been thoroughly studied for research and translational bone regeneration purposes. rhBMP-2 induces bone formation in vivo, and hBM-MSCs are its target, bone-forming cells. In this article, we studied how rhBMP-2 drives the multilineage differentiation of hBM-MSCs both in vivo and in vitro. METHODS: rhBMP-2 and hBM-MSCs were tested in an in vivo subcutaneous implantation model to assess their ability to form mature bone and undergo multilineage differentiation. Then, the hBM-MSCs were treated in vitro with rhBMP-2 for short-term or long-term cell-culture periods, alone or in combination with osteogenic, adipogenic or chondrogenic media, aiming to determine the role of rhBMP-2 in these differentiation processes. RESULTS: The data indicate that hBM-MSCs respond to rhBMP-2 in the short term but fail to differentiate in long-term culture conditions; these cells overexpress the rhBMP-2 target genes DKK1, HEY-1 and SOST osteogenesis inhibitors. However, in combination with other differentiation signals, rhBMP-2 acts as a potentiator of multilineage differentiation, not only of osteogenesis but also of adipogenesis and chondrogenesis, both in vitro and in vivo. CONCLUSIONS: Altogether, our data indicate that rhBMP-2 alone is unable to induce in vitro osteogenic terminal differentiation of hBM-MSCs, but synergizes with other signals to potentiate multiple differentiation phenotypes. Therefore, rhBMP-2 triggers on hBM-MSCs different specific phenotype differentiation depending on the signalling environment.

Activation of estrogen receptor induces differential proteomic responses mainly involving migration, invasion, and tumor development pathways in human testicular embryonal carcinoma NT2/D1 cells.

The aims of the present study were to investigate the global changes on proteome of human testicular embryonal carcinoma NT2/D1 cells treated with 17ß-estradiol (E2), and the effects of this hormone on migration, invasion, and colony formation of these cells. A quantitative proteomic analysis identified the presence of 1230 proteins in both E2-treated and control cells. The analysis revealed 75 differentially abundant proteins (DAPs), out of which 43 proteins displayed a higher abundance and, 30 proteins showed a lower abundance in E2-treated NT2/D1 cancer cells. Functional analysis using IPA highlighted some activation processes such as migration, invasion, metastasis, and tumor growth. Interestingly, the treatment with E2 and ERß-selective agonist DPN increased the migration of NT2/D1 cells. On the other hand, ERα-selective agonist PPT did not modify cell migration, indicating that ERß is the upstream receptor involved in this process. The activation of ERß increased the invasion and anchorage­independent growth of NT2/D1 cells more intensely than ERα. ERα and ERß may play overlapping roles on invasion and colony formation of these cells. Further studies are required to clarify the mechanism underlying these effects. The molecular mechanisms revealed by proteomic and functional studies might also guide the development of potential targets for a better understanding of the biology of these cells and novel treatments for non-seminoma in the future.

Estrogen receptors regulate galectin­3 in androgen­independent DU­145 prostate cancer cells.

The aim of the present study was to investigate the role of estrogen receptor (ER)α and ERß, and galectin­3 (GAL­3) in migration and invasion of androgen­independent DU­145 prostate cancer cells, and to examine the regulation of the expression of GAL­3 by the activation of these receptors. Wound healing and cell invasion assays were performed using the control (basal level of cellular function) and treated DU­145 cells. At 24 h of treatment, 17ß­estradiol (E2), the ERα­selective agonist, 4,4',4"­(4­propyl­(1H)­pyrazole­1,3,5­triyl)trisphenol (PPT), or the ERß­selective agonist, 2,3­bis(4­hydroxyphenyl)­propionitrile (diarylprepionitrile; DPN), increased the migration and invasion of the DU­145 cells. Pre­treatment with the ERα­ and ERß­selective antagonists blocked these effects, indicating that ERα and ERß are upstream receptors regulating these processes. Western blot analysis and immunofluorescence staining for the detection of the GAL­3 were performed using the control and treated DU­145 cells. Treatment of the DU­145 cells with E2, PPT or DPN for 24 h increased the expression of the GAL­3 compared to the control. Furthermore, a specific inhibitor of GAL­3 (VA03) inhibited the migration and invasion of DU­145 cells, indicating the involvement of the complex ERα/GAL­3 and ERß/GAL­3 in the regulation of these processes. On the whole, the present study demonstrates that the activation of both ERs increases the expression and signaling of GAL­3, and promotes the migration and invasion of DU­145 cells. The findings of the present study provide novel insight into the signatures and molecular mechanisms of ERα and ERß in DU­145 cells.

Electrocoagulation treatment of furniture industry wastewater.

Electrocoagulation was investigated as a method for treating wastewater containing polyvinyl acetate (PVAc) from the furniture industry. The study evaluated the evolution of iron concentration and passivation during the treatment process. Laboratory-scale experiments were conducted to evaluate the effects of inter-electrode distance (d), current density, and mode on treatment performance. Three values of d (0.3, 0.6, and 0.9 cm) were studied and found to have no significant effect on performance. However, lower d values resulted in reduced energy consumption due to a decrease in applied voltage. Three values of current density (132, 158, and 197 A m-2) were studied under two current modes, Direct Current (DC) and Alternating Pulsed Current (APC). The best treatment performance for DC occurred under 158 A m-2 (the treated wastewater was characterized by pH = 4.59 ± 0.02, conductivity = 996 ± 21 µS cm-1, COD = 1940 ± 55 mgO2 L-1, TSS = 105 ± 14 mg L-1, and Fe = 50.39 ± 1.87 mgFe L-1). For APC, the best performance was achieved under 197 A m-2 (the treated wastewater was characterized by pH = 6.33 ± 0.06, conductivity = 988 ± 17 µS cm-1, COD = 1942 ± 312 mgO2 L-1, TSS = 199 ± 55 mg L-1, and Fe = 44.68 ± 4.60 mgFe L-1). Despite the promising results, treatment performance was insufficient to meet the legal requirements for water discharge. APC was found to be a more economically viable approach, as it reduced anode wear, electrode passivation, and energy consumption. The quantity of iron released increased with d, and the effect of current density on iron concentration was found to be non-linear. However, applying APC reduced the iron content for all tested current densities. The tests showed that EC was effective in removing chemical oxygen demand (COD) and total suspended solids (TSS), achieving removal efficiencies above 92% and 99%, respectively. However, the studied treatment procedures were insufficient to meet the EU legal requirements for water discharge. Therefore, the obtained wastewater should undergo a post-treatment process.

Molecular regulation of prostate cancer by Galectin-3 and estrogen receptor.

Prostate cancer remains the most prevalent cancer among men worldwide. This cancer is hormone-dependent; therefore, androgen, estrogen, and their receptors play an important role in development and progression of this disease, and in emergence of the castration-resistant prostate cancer (CRPC). Galectins are a family of ß-galactoside-binding proteins which are frequently altered (upregulated or downregulated) in a wide range of tumors, participating in different stages of tumor development and progression, but the molecular mechanisms which regulate its expression are still poorly understood. This review provides an overview of the current and emerging knowledge on Galectin-3 in cancer biology with focus on prostate cancer and the interplay with estrogen receptor (ER) signaling pathways, present in androgen-independent prostate cancer cells. We suggest a molecular mechanism where ER, Galectin-3 and ß-catenin can modulate nuclear transcriptional events, such as, proliferation, migration, invasion, and anchorage-independent growth of androgen-independent prostate cancer cells. Despite a number of achievements in targeted therapy for prostate cancer, CRPC may eventually develop, therefore new effective drug targets need urgently to be found. Further understanding of the role of Galectin-3 and ER in prostate cancer will enhance our understanding of the molecular mechanisms of prostate cancer development and the future treatment of this disease.

Activation of estrogen receptor ESR1 and ESR2 induces proliferation of the human testicular embryonal carcinoma NT2/D1 cells.

The aims of the present study were to investigate the expression of the classic estrogen receptors ESR1 and ESR2, the splicing variant ESR1-36 and GPER in human testicular embryonal carcinoma NT2/D1 cells, and the effects of the activation of the ESR1 and ESR2 on cell proliferation. Immunostaining of ESR1, ESR2, and GPER were predominantly found in the nuclei, and less abundant in the cytoplasm. ESR1-36 isoform was predominantly expressed in the perinuclear region and cytoplasm, and some weakly immunostained in the nuclei. In nonstimulated NT2/D1 cells (control), proteins of the cell cycle CCND1, CCND2, CCNE1 and CDKN1B are present. Activation of ESR1 and ESR2 increases, respectively, CCND2 and CCNE1 expression, but not CCND1. Activation of ESR2 also mediates upregulation of the cell cycle inhibitor CDKN1B. This protein co-immunoprecipitated with CCND2. Also, E2 induces an increase in the number and viability of the NT2/D1 cells. These effects are blocked by simultaneous pretreatment with ESR1-and ESR2-selective antagonists, confirming that both estrogen receptors regulate NT2/D1 cell proliferation. In addition, E2 increases SRC phosphorylation, and SRC mediates cell proliferation. Our study provides novel insights into the signatures and molecular mechanisms of estrogen receptor in NT2/D1 cells.

The Glypican proteoglycans show intrinsic interactions with Wnt-3a in human prostate cancer cells that are not always associated with cascade activation.

BACKGROUND: Prostate cancer occurs through multiple steps until advanced metastasis. Signaling pathways studies can result in the identification of targets to interrupt cancer progression. Glypicans are cell surface proteoglycans linked to the membrane through glycosylphosphatidylinositol. Their interaction with specific ligands has been reported to trigger diverse signaling, including Wnt. In this study, prostate cancer cell lines PC-3, DU-145, and LNCaP were compared to normal prostate RWPE-1 cell line to investigate glypican family members and the activation of the Wnt signaling pathway. RESULTS: Glypican-1 (GPC1) was highly expressed in all the examined cell lines, except for LNCaP, which expressed glypican-5 (GPC5). The subcellular localization of GPC1 was detected on the cell surface of RWPE-1, PC-3, and DU-145 cell lines, while GPC5 suggested cytoplasm localization in LNCaP cells. Besides glypican, flow cytometry analysis in these prostate cell lines confirmed the expression of Wnt-3a and unphosphorylated ß-catenin. The co-immunoprecipitation assay revealed increased levels of binding between Wnt-3a and glypicans in cancer cells, suggesting a relationship between these proteoglycans in this pathway. A marked increase in nuclear ß-catenin was observed in tumor cells. However, only PC-3 cells demonstrated activation of canonical Wnt signaling, according to the TOPFLASH assay. CONCLUSIONS: GPC1 was the majorly expressed gene in all the studied cell lines, except for LNCaP, which expressed GPC5. We assessed by co-immunoprecipitation that these GPCs could interact with Wnt-3a. However, even though nuclear ß-catenin was found increased in the prostate cancer cells (i.e., PC-3, DU-145 and LNCaP), activation of Wnt pathway was only found in PC-3 cells. In these PC-3 cells, GPC1 and Wnt-3a revealed high levels of colocalization, as assessed by confocal microscopy studies. This suggests a localization at the cellular surface, where Frizzled receptor is required for downstream activation. The interaction of Wnt-3a with GPCs in DU-145 and LNCaP cells, which occurs in absence of Wnt signaling activation, requires further studies. Once non-TCF-LEF proteins can also bind ß-catenin, another signaling pathway may be involved in these cells with regulatory function.

Estrogen Receptor Signaling Pathways Involved in Invasion and Colony Formation of Androgen-Independent Prostate Cancer Cells PC-3.

Castration-resistant prostate cancer (CRPC) is an advanced and androgen-independent form of prostate cancer. Recent studies of rapid actions mediated by estrogen in the prostate and its relationship with CRPC are emerging. We have previously shown that estrogen receptor (ER) promotes migration and invasion of the androgen-independent prostate cancer cells PC-3, but the signaling pathways involved in these events remain to be elucidated. Therefore, this study aimed to analyze the role of ERα and ERß in the activation of SRC, and the involvement of SRC and PI3K/AKT on invasion and colony formation of the PC-3 cells. Our results showed that the activation of ERα (using ERα-selective agonist PPT) and ERß (using ERß-selective agonist DPN) increased phosphorylation of SRC in PC-3 cells. In the presence of the selective inhibitor for SRC-family kinases PP2, the effects of DPN and PPT on transmigration and soft agar colony formation assays were decreased. Furthermore, SRC is involved in the expression of the non-phosphorylated ß-catenin. Finally, using PI3K specific inhibitor Wortmannin and AKT inhibitor MK2206, we showed that PI3K/AKT are also required for invasion and colony formation of PC-3 cells simulated by ER. This study provides novel insights into molecular mechanisms of ER in PC-3 cells by demonstrating that ER, located outside the cell nucleus, activates rapid responses molecules, including SRC and PI3K/AKT, which enhance the tumorigenic potential of prostate cancer cells, increasing cell proliferation, migration, invasion, and tumor formation.

EcTI impairs survival and proliferation pathways in triple-negative breast cancer by modulating cell-glycosaminoglycans and inflammatory cytokines.

Breast cancer is the most common malignant tumor among women worldwide, and triple-negative breast cancer is the most aggressive type of breast cancer, which does not respond to hormonal therapies. The protease inhibitor, EcTI, extracted from seeds of Enterolobium contortisiliquum, acts on the main signaling pathways of the MDA-MB-231 triple-negative breast cancer cells. This inhibitor, when bound to collagen I of the extracellular matrix, triggers a series of pathways capable of decreasing the viability, adhesion, migration, and invasion of these cells. This inhibitor can interfere in the cell cycle process through the main signaling pathways such as the adhesion, Integrin/FAK/SRC, Akt, ERK, and the cell death pathway BAX and BCL-2. It also acts by reducing the main inflammatory cytokines such as TGF-α, IL-6, IL-8, and MCP-1, besides NFκB, a transcription factor, responsible for the aggressive and metastatic characteristics of this type of tumor. Thus, the inhibitor was able to reduce the main processes of carcinogenesis of this type of cancer.

Estrogen Receptors Promote Migration, Invasion and Colony Formation of the Androgen-Independent Prostate Cancer Cells PC-3 Through ß-Catenin Pathway.

Prostate cancer is initially dependent on the androgen, gradually evolves into an androgen-independent form of the disease, also known as castration-resistant prostate cancer (CRPC). At this stage, current therapies scantily improve survival of the patient. Androgens and estrogens are involved in normal prostate and prostate cancer development. The mechanisms by which estrogens/estrogen receptors (ERs) induce prostate cancer and promote prostate cancer progression have not yet been fully identified. Our laboratory has shown that androgen-independent prostate cancer cells PC-3 express both ERα and ERß. The activation of ERß increases the expression of ß-catenin and proliferation of PC-3 cells. We now report that the activation of ERß promotes the increase of migration, invasion and anchorage-independent growth of PC-3 cells. Furthermore, the activation of ERα also plays a role in invasion and anchorage-independent growth of PC-3 cells. These effects are blocked by pretreatment with PKF 118-310, compound that disrupts the complex ß-catenin/TCF/LEF, suggesting that ERs/ß-catenin are involved in all cellular characteristics of tumor development in vitro. Furthermore, PKF 118-310 also inhibited the upregulation of vascular endothelial growth factor A (VEGFA) induced by activation of ERs. VEGF also is involved on invasion of PC-3 cells. In conclusion, this study provides novel insights into the signatures and molecular mechanisms of ERß in androgen-independent prostate cancer cells PC-3. ERα also plays a role on invasion and colony formation of PC-3 cells.

EcTI impairs survival and proliferation pathways in triple-negative breast cancer by modulating cell-glycosaminoglycans and inflammatory cytokines

Breast cancer is the most common malignant tumor among women worldwide, and triple-negative breast cancer is the most aggressive type of breast cancer, which does not respond to hormonal therapies. The protease inhibitor, EcTI, extracted from seeds of Enterolobium contortisiliquum, acts on the main signaling pathways of the MDA-MB-231 triple-negative breast cancer cells. This inhibitor, when bound to collagen I of the extracellular matrix, triggers a series of pathways capable of decreasing the viability, adhesion, migration, and invasion of these cells. This inhibitor can interfere in the cell cycle process through the main signaling pathways such as the adhesion, Integrin/FAK/SRC, Akt, ERK, and the cell death pathway BAX and BCL-2. It also acts by reducing the main inflammatory cytokines such as TGF-α, IL-6, IL-8, and MCP-1, besides NFκB, a transcription factor, responsible for the aggressive and metastatic characteristics of this type of tumor. Thus, the inhibitor was able to reduce the main processes of carcinogenesis of this type of cancer.

Crataeva tapia bark lectin (CrataBL) is a chemoattractant for endothelial cells that targets heparan sulfate and promotes in vitro angiogenesis.

Formation of new blood vessels from preexisting ones, a process known as angiogenesis, is one of the limiting steps for success in treatment of ischemic disorders. Therefore, efforts to understanding and characterize new agents capable to stimulate neovascularization are a worldwide need. Crataeva tapia bark lectin (CrataBL) has been shown to have chemoattractant properties for endothelial cells through the stimulation of migration and invasiveness of human umbilical vein endothelial cells (HUVEC) because it is a positively charged protein with high affinity to glycosaminoglycan. In addition, CrataBL increased the production of chondroitin and heparan sulfate in endothelial cells. These findings orchestrated specific adhesion on collagen I and phosphorylation of tyrosine kinase receptors, represented by vascular endothelial growth factor receptor-2 (VEGFR-2) and fibroblast growth factor receptor (FGFR), whose downstream pathways trigger the angiogenic cascade increasing cell viability, cytoskeleton rearrangement, cell motility, and tube formation. Moreover, CrataBL inhibited the activity of matrix metalloproteases type 2 (MMP-2), a protein related to tissue remodeling. Likewise, CrataBL improved wound healing and increased the number of follicular structures in lesioned areas produced in the dorsum-cervical region of C57BL/6 mice. These outcomes altogether indicate that CrataBL is a pro-angiogenic and healing agent.

Estrogen receptors localization and signaling pathways in DU-145 human prostate cancer cells.

The aim of the present study was to investigate the subcellular localization of estrogen receptors ERα and ERß in androgen-independent prostate cancer cell line DU-145, and the possible role of exportin CRM1 on ERs distribution. In addition, we evaluated the ERs contribution to activation of ERK1/2 and AKT. Immunostaining of ERα and ERß was predominantly found in the extranuclear regions of DU-145 cells. CRM1 inhibitor Leptomycin B reduced drastically the presence of ERα and ERß in the extranuclear regions and increased in the nuclei, indicating the possible involvement of CRM1 on ERs nuclear-cytoplasmic shuttling. 17ß-estradiol (E2), ERα-selective agonist PPT and ERß-selective agonist DPN induced a rapid increase on ERK1/2 phosphorylation. E2-induced ERK1/2 activation was partially inhibited when cells were pretreated with ERα- or ERß-selective antagonists, and blocked by simultaneous pretreatment with both antagonists, suggesting ERα/ß heterodimers formation. Furthermore, E2 treatment did not activate AKT pathway. Therefore, we highlighted a possible crosstalk between extranuclear and nuclear ERs and their upstream and downstream signaling molecules as an important mechanism to control ER function as a potential therapeutic target in prostate cancer cells.

Heparan Sulfate Proteoglycans in Human Colorectal Cancer.

Colorectal cancer is the third most common cancer worldwide, accounting for more than 610,000 mortalities every year. Prognosis of patients is highly dependent on the disease stage at diagnosis. Therefore, it is crucial to investigate molecules involved in colorectal cancer tumorigenesis, with possible use as tumor markers. Heparan sulfate proteoglycans are complex molecules present in the cell membrane and extracellular matrix, which play vital roles in cell adhesion, migration, proliferation, and signaling pathways. In colorectal cancer, the cell surface proteoglycan syndecan-2 is upregulated and increases cell migration. Moreover, expression of syndecan-1 and syndecan-4, generally antitumor molecules, is reduced. Levels of glypicans and perlecan are also altered in colorectal cancer; however, their role in tumor progression is not fully understood. In addition, studies have reported increased heparan sulfate remodeling enzymes, as the endosulfatases. Therefore, heparan sulfate proteoglycans are candidate molecules to clarify colorectal cancer tumorigenesis, as well as important targets to therapy and diagnosis.

O sismo de 1755: a atuação do enfermeiro na assistência aos feridos de Lisboa / The 1755 Lisbon earthquake: the work of nurses in the care provided to the wounded

Este estudo teve por objetivo analisar o cuidado prestado por enfermeiros aos feridos e enfermos do terramoto de 1755, em Lisboa. Realizou-se uma pesquisa documental das fontes primárias identifi cadas, utilizaram-se as Portarias do Governo sobre o tratamento dos feridos, a assistência aos enfermos e a sua situação após o terramoto. Foi ainda analisado o livro das Enfermarias das Portas de Santo Antão, da Casa dos Almadas no Rossio e em São Bento da Saúde, após o terramoto, em 1755. A análise destes documentos permitiu desvelar várias dimensões da assistência pós-terramoto, nomeadamente no que respeitou à admissão e registo das entradas nas enfermarias provisórias. Conclui-se que houve enfermeiros religiosos e leigos do Hospital Real de Todos os Santos envolvidos na assistência a feridos e enfermos, com a clara indicação de que esses enfermeiros eram treinados

Analysis of proteoglycan expression in human dental pulp.

Proteoglycans are glycosylated proteins which have covalently attached highly anionic glycosaminoglycans. They can be located on the extracellular matrix, cell membrane or intracellular granules. To date, few studies have reported the presence of proteoglycans in human dental pulp. OBJECTIVE: The aim of this study was, therefore, to analyze the expression of lumican, versican and glypican proteoglycans in deciduous and permanent human dental pulp by real-time polymerase chain reaction (q-PCR) and immunofluorescence. DESIGN: Healthy human dental pulps were used: 13 from permanent teeth (group 1) and eight from deciduous teeth (group 2). Versican, lumican and glypican (glypican-1 to 6) gene expressions were quantitatively evaluated by real-time PCR technique, using the expression of the endogenous gene GAPDH as control. Pulp sections were submitted to immunostaining procedure with fluorescence labelling, the tissues being fixed and incubated with well-characterized monoclonal and polyclonal antibodies against proteoglycan epitopes, including anti-versican and anti-lumican. Comparisons among the groups of the quantitative scores for each proteoglycan were analyzed using the t-test and ANOVA (P < 0.05). RESULTS: The real-time PCR analysis showed expression of versican and lumican proteoglycans in the two groups, with significant predominance of lumican gene (P = 0.03). Considering the glypican genes, glypican-3 was the proteoglycan most significantly expressed in permanent pulps (P < 0.001), while glypican-2 was not expressed in this tissue. The immunofluorescence quantification exhibited no significant differences between lumican and versican among the pulps and groups. CONCLUSIONS: The lumican gene was more expressed than versican and glypican-3 was the isoform more expressed in permanent pulp compared to deciduous.

Activation of estrogen receptor beta (ERß) regulates the expression of N-cadherin, E-cadherin and ß-catenin in androgen-independent prostate cancer cells.

The aim of the present study was to investigate the impact of the activation of estrogen receptors on expression and localization of N-cadherin, E-cadherin and non-phosphorylated ß-catenin in androgen-independent prostate cancer cells (PC-3 and DU-145) and in human post pubertal prostate epithelial cells (PNT1A). Expression of N-cadherin was detected in PNT1A and PC-3 cells, but not in DU-145 cells. E-cadherin was detected only in DU-145 cells and ß-catenin was detected in all cells studied. N-cadherin and ß-catenin were located preferentially in the cellular membrane of PNT1A cells and in the cytoplasm of PC-3 cells. E-cadherin and ß-catenin were located preferentially in the cellular membrane of DU-145 cells. 17ß-estradiol (E2) or the ERα-selective agonist PPT did not affect the content and localization of N-cadherin in PC-3 and PNT1A cells or E-cadherin in DU-145 cells. In PC-3 cells, ERß-selective agonist DPN decreased the expression of N-cadherin. DPN-induced downregulation of N-cadherin was blocked by pretreatment with the ERß-selective antagonist (PHTPP), indicating that ERß1 is the upstream receptor regulating the expression of N-cadherin. In DU-145 cells, the activation of ERß1 by DPN increased the expression of E-cadherin. Taken together, these results suggest that activation of ERß1 is required to maintain an epithelial phenotype in PC-3 and DU-145 cells. The activation of ERß1 also increased the expression of ß-catenin in cytoplasm of PC-3 and in the cellular membrane of DU-145 cells. In conclusion, our results indicate differential expression and localization of N-cadherin, E-cadherin and ß-catenin in androgen-independent prostate cancer cells. The reduction of N-cadherin content by activation of ERß, exclusively observed in androgen-independent prostate cancer cells (PC-3), may be related to the activation of signaling pathways, such as the release of ß-catenin into the cytoplasm, translocation of ß-catenin to the nucleus and activation of gene transcription.

Macroporous Calcium Phosphate/Chitosan Composites Prepared via Unidirectional Ice Segregation and Subsequent Freeze-Drying.

Calcium phosphate chitosan-based composites have gained much interest in recent years for biomedical purposes. In this paper, three-dimensional calcium phosphate chitosan-based composites with different mineral contents were produced using a green method called ice segregation induced self-assembly (ISISA). In this methodology, ice crystals were used as a template to produce porous structures from an aqueous solution of chitosan (CS) and hydroxyapatite (Hap) also containing acetic acid (pH = 4.5). For better characterization of the nature of the inorganic matter entrapped within the resulting composite, we performed either oxygen plasma or calcination processes to remove the organic matter. The nature of the phosphate salts was studied by XRD and NMR studies. Amorphous calcium phosphate (ACP) was identified as the mineral phase in the composites submitted to oxygen plasma, whereas crystalline Hap was obtained after calcination. SEM microscopy revealed the formation of porous structures (porosity around 80-85%) in the original composites, as well as in the inorganic matrices obtained after calcination, with porous channels of up to 50 µm in diameter in the former case and of up to 20 µm in the latter. The biocompatibility of the composites was assessed using two different cell lines: C2C12GFP premyoblastic cells and MC3T3 preosteoblastic cells.

SEROPREVALENCE OF HTLV IN A POPULATION OF HIV1-INFECTED PATIENTS IN MIDWESTERN BRAZIL.

Human T-cell lymphotropic virus (HTLV) may affect the clinical course of human immunodeficiency virus 1 (HIV1). Both infections are common in endemic areas because these viruses share similar routes of transmission. The aim of this study was to estimate the seroprevalence of HTLV1/2 in a population of HIV1-infected patients in the state of Goiás, Midwestern Brazil. Of the 505 studied patients, four (0.79%) were positive for anti-HTLV1/2 by enzyme-linked immunosorbent assay (ELISA), with HTLV1 infection confirmed by line immunoassay (LIA) and polymerase chain reaction (PCR) in all of the ELISA-positive samples. No cases of HTLV2 infection were observed. The prevalence of HTLV1/HIV1 coinfection was 0.79% (4/505; 95% CI: 0.25-2.16). All the coinfected patients reported sexual risk behaviors and only one reported intravenous drug use. Sequencing of the viral long terminal repeat (LTR) region and phylogenetic analysis revealed that the four HTLV1 isolates belonged to the Transcontinental a subgroup of the Cosmopolitan (1a) subtype, the most frequent subgroup detected in Brazil. This study shows a low prevalence of HTLV1/2 in HIV1-infected patients in Midwestern Brazil.

Estrogen receptor beta (ERß) mediates expression of ß-catenin and proliferation in prostate cancer cell line PC-3.

The aim of the present study was to characterize the mechanism underlying estrogen effects on the androgen-independent prostate cancer cell line PC-3. 17ß-estradiol and the ERß-selective agonist DPN, but not the ERα-selective agonist PPT, increased the incorporation of [methyl-(3)H]thymidine and the expression of Cyclin D2, suggesting that ERß mediates the proliferative effect of estrogen on PC-3 cells. In addition, upregulation of Cyclin D2 and incorporation of [methyl-(3)H]thymidine induced by 17ß-estradiol and DPN were blocked by the ERß-selective antagonist PHTPP in PC-3 cells. Upregulation of Cyclin D2 and incorporation of [methyl-(3)H]thymidine induced by DPN were also blocked by PKF118-310, a compound that disrupts ß-catenin-TCF (T-cell-specific transcription factor) complex, suggesting the involvement of ß-catenin in the estradiol effects in PC-3 cells. A diffuse immunostaining for non-phosphorylated ß-catenin was detected in the cytoplasm of PC-3 cells. Low levels of non-phosphorylated ß-catenin immunostaining were also detected near the plasma membrane and in nuclei. Treatment of PC-3 cells with 17ß-estradiol or DPN markedly increased non-phosphorylated ß-catenin expression. These effects were blocked by pretreatment with the ERß-selective antagonist PHTPP, PI3K inhibitor Wortmannin or AKT inhibitor MK-2206, indicating that ERß-PI3K/AKT mediates non-phosphorylated ß-catenin expression. Cycloheximide blocked the DPN-induced upregulation of non-phosphorylated ß-catenin, suggesting de novo synthesis of this protein. In conclusion, these results suggest that estrogen may play a role in androgen-independent prostate cancer cell proliferation through a novel pathway, involving ERß-mediated activation of ß-catenin.