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International audience; Multidrug resistance (MDR) in cancer cells is often associated with overexpression of ATP-binding cassette (ABC) transporters, including P-glycoprotein (P-gp/ABCB1), multidrug resistance-associated protein 1 (MRP1/ABCC1) and breast cancer resistance protein (BCRP/ABCG2). Modulators of these transporters might be helpful in overcoming MDR. Moreover, exploiting collateral sensitivity (CS) could be another approach for efficient treatment of cancer. Twelve novel 5-oxo-hexahydroquinoline derivatives bearing different aromatic substitutions at C 4 , while having 2-pyridyl alkyl carboxylate substituents at the C 3 were synthesized and evaluated for MDR reversal activity by flow cytometric determination of rhodamine 123, calcein and mitoxantrone accumulations in P-gp, MRP1 and BCRP-overexpressing cell lines, respectively. Furthermore, to confirm the P-gp inhibitory activity, the effect of compounds on the reduction of doxorubicin's IC 50 of drug-resistant human uterine sarcoma cell line, MES-SA/DX5, was evaluated. Compounds D6, D5 and D3 (bearing 3-chlorophenyl, 2,3-dichlorophenyl and 4-chlorophenyl substituents at C 4 position of 5-oxo-hexahydroquinoline core) were the most potent P-gp, MRP1 and BCRP inhibitors, respectively, causing significant MDR reversal at concentrations of 1-10 μM. Additionally, D4 (containing 3-flourophenyl) was the most effective MRP1-dependent CS inducing agent. Overall, chlorine containing compounds D6, C4 and D3 were capable of significant inhibition of all 3 important efflux pumps in cancer cells. Moreover, D6 also induced CS triggered by reducing glutathione efflux. In conclusion, some of the 5-oxo-hexahydroquinoline derivatives are effective efflux pump inhibitors capable of simultaneously blocking 3 important ABC transporters involved in MDR, and represent promising agents to overcome MDR in cancer cells.

Summary The Hsp90 chaperone promotes folding and activation of hundreds of client proteins in the cell through an ATP-dependent conformational cycle guided by distinct cochaperone regulators. The FKBP51 immunophilin binds Hsp90 with its tetratricopeptide repeat (TPR) domain and catalyzes peptidyl-prolyl isomerase (PPIase) activity during folding of kinases, nuclear receptors, and tau. Here we determined the cryoelectron microscopy (cryo-EM) structure of the human Hsp90:FKBP51:p23 complex to 3.3 A, which, together with mutagenesis and crosslinking analyses, reveals the basis for cochaperone binding to Hsp90 during client maturation. A helix extension in the TPR functions as a key recognition element, interacting across the Hsp90 C-terminal dimer interface presented in the closed, ATP conformation. The PPIase domain is positioned along the middle domain, adjacent to Hsp90 client binding sites, whereas a single p23 makes stabilizing interactions with the N-terminal dimer. With this architecture, FKBP51 is positioned to act on specific client residues presented during Hsp90-catalyzed remodeling.

Herein, we investigated efflux pumps-mediated talazoparib-resistance in the treatment of triple-negative breast cancer (TNBC). Furthermore, we produced a novel talazoparib-solid lipid nanoparticles (SLNs) and then explored in vitro therapeutic efficacy of talazoparib-SLNs to overcome talazoparib-resistance in TNBC cells. Talazoparib-SLNs formulation was produced and then characterized. Calcein and Rho-123 were used to analyze the functional activity of drug efflux pumps in these cells. Additionally, RT-PCR, western blot and immunofluorescence analysis were used to detect the messenger RNA, and protein expression level, and cellular localization of the multidrug resistance (MDR1), breast cancer resistance protein (BCRP), and MRP1. We found that talazoparib efflux was mediated by BCRP and MRP1 pumps in TNBC cells. Talazoparib-SLNs could significantly enhance therapeutic efficacy of talazoparib. Furthermore, talazoparib-SLNs were more effective in the suppression of MDR1, BCRP, and MRP1 gene and protein expression levels than talazoparib. Consequently, this study suggests that talazoparib-SLNs formulation represents a promising therapeutic carrier to reverse MDR-mediated resistance in TNBC.

LiTCTP is a toxin from the Translationally Controlled Tumor Protein (TCTP) family identified in Loxosceles brown spider venoms. These proteins are known as histamine-releasing factors (HRF). TCTPs participate in allergic and anaphylactic reactions, which suggest their potential role as therapeutic targets. The histaminergic effect of TCTP is related to its pro-inflammatory functions. An initial characterization of LiTCTP in animal models showed that this toxin can increase the microvascular permeability of skin vessels and induce paw edema in a dose-dependent manner. We evaluated the role of LiTCTP in vitro and in vivo in the inflammatory and allergic aspects that undergo the biological responses observed in Loxoscelism, the clinical condition after an accident with Loxosceles spiders. Our results showed LiTCTP recombinant toxin (LiRecTCTP) as an essential synergistic factor for the dermonecrotic toxin actions (LiRecDT1, known as the main toxin in the pathophysiology of Loxoscelism), revealing its contribution to the exacerbated inflammatory response clinically observed in envenomated patients.

Brown spider envenomation results in dermonecrosis with gravitational spreading characterized by a marked inflammatory reaction and with lower prevalence of systemic manifestations such as renal failure and hematological disturbances. Several toxins make up the venom of these species, and they are mainly peptides and proteins ranging from 5–40 kDa. The venoms have three major families of toxins: phospholipases-D, astacin-like metalloproteases, and the inhibitor cystine knot (ICK) peptides. Serine proteases, serpins, hyaluronidases, venom allergens, and a translationally controlled tumor protein (TCTP) are also present. Toxins hold essential biological properties that enable interactions with a range of distinct molecular targets. Therefore, the application of toxins as research tools and clinical products motivates repurposing their uses of interest. This review aims to discuss possibilities for brown spider venom toxins as putative models for designing molecules likely for therapeutics based on the status quo of brown spider venoms. Herein, we explore new possibilities for the venom components in the context of their biochemical and biological features, likewise their cellular targets, three-dimensional structures, and mechanisms of action.

Oncogenes are mutated form of normal cellular genes called as proto-oncogenes and conduce to the cancer development process. Despite the fact that so many genes have been described, new genes with oncogenic characteristic and potential or tumor supressoring activity are still being defined. Recently, Up-regulated gene 4/Upregulator of cell proliferation (URG4/URGCP), a novel gene, induced by hepatitis-Bvirus-encoded X antigen (HBxAg), has been identified. URG4/URGCP gene was registered to the National Center for Biotechnology Information-GenBank (NCBI-GenBank, Entrez GeneID: 55665 and Entrez Nucleotide ID NM_017920). URG4/URGCP is located on the short arm of chromosome 7 (7p13) and synthesizes a protein containing 922 amino acids in the cytoplas. Relationship between URG4/URGCP expression and clinicopathologic characteristics were evaluated and significant results were in various cancer types such as hepatocellular carcinoma, osteosarcoma, nasopharyngeal carcinoma, bladder cancer, gastric cancer and glioma. Although, biological activity of URG4/URGCP and its effect mechanism in malignant cells is not fully understood, all interesting and promising results shows that URG4/URGCP may be a putative oncogene that contributes to multistep carcinogenesis, cell cycle regulation and other important biological process in the cell. © 2018 Elsevier B.V.

P-glycoprotein (Pgp) and breast cancer resistance protein (BCRP) are ATP binding cassette (ABC) transporters that are overexpressed in different drug-resistant cancer cell lines. In this study, we investigated whether doxorubicin promotes Pgp and/or BCRP expression to induce drug resistance in colon cancer cells under hypoxic conditions. We analyzed HIF-1? activity via ELISA, Pgp, and BCRP expression by qRT-PCR and the relationship between doxorubicin uptake and ABC transporter expression via confocal microscopy in HT-29WT and HT-29 doxorubicin-resistant colon cancer cells (HT-29DxR). These cells were treated with doxorubicin and/or CoCl2 (chemical hypoxia), and reactive oxygen species inductors. We found that the combination of chemically induced hypoxia and doxorubicin promoted Pgp mRNA expression within 24 h in HT-29WT and HT-29DxR cells. Both doxorubicin and CoCl2 alone or in combination induced Pgp and BCRP expression, as demonstrated via confocal microscopy in each of the above two cell lines. Thus, we surmised that Pgp and BCRP expression may result from synergistic effects exerted by the combination of doxorubicin-induced ROS production and HIF-1? activity under hypoxic conditions. However, HIF-1? activity disruption via the administration of E3330, an APE-1 inhibitor, downregulated Pgp expression and increased doxorubicin delivery to HT-29 cells, where it served as a substrate for Pgp, indicating the existence of an indirect relationship between Pgp expression and doxorubicin accumulation. Thus, we concluded that Pgp and BCRP expression can be regulated via cross-talk between doxorubicin and hypoxia, promoting drug resistance in HT-29 WT, and HT-29DxR cells and that this process may be ROS dependent. J. Cell. Biochem. 118: 1868–1878, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

The dysregulation of miRNA expression has frequently been observed in breast cancer. Therefore, we investigated the expression profile of miRNAs that may be associated with expression of the FHIT gene in breast cancer and assessed their clinicopathological significance. The expression levels of miR-143, miR-663a, miR-668, miR-922 and FHIT were analyzed in normal and malignant breast tissues from 65 patients with breast cancer. We studied the correlation between the expression of miR-143, miR-663a, miR-668, miR-922 and FHIT and the clinicopathological features presented by the patients. The expression levels of the miRNAs and FHIT were downregulated in breast cancer tissue. The expression levels of miR-143, miR-663a and miR-668 were significantly reduced in FHIT downregulated tumors. miR-668 expression was also significantly altered relative to FHIT down- and up- regulated tumor tissues. Reduced miR-663a expression was statistically associated with high-grade ER/PR (+) status, benign reactive hyperplasia, lymph-node metastasis, in-situ component >25% and Ki 67 > 15% compared with non-tumor tissues. Additionally, reduced miR-668 expression was significantly different between tumors with and without lymph-node metastasis. miR-668 may play an important role in breast cancer development and progression by regulating the expression of FHIT. Furthermore, miR-668 and miR-663a may be potential prognostic biomarkers for breast cancer.

Molecular studies have an important role in the elucidation of the mechanisms involved in Glioblastoma multiforme (GBM) development. The occurrence of FHIT gene alterations, which has an important role in different cancers, has not yet been studied well in GBM. We aimed to investigate the occurrence of alterations of FHIT gene sequence and protein expression in the GBMs. Sequence alterations in exons 5-9 of the FHIT gene were screened in 63 GBMs using the single-strand conformational polymorphism method, followed by DNA sequencing. Additionally, the level of Fhit protein expression in tissues of 48 tumors was assessed by immunohistochemistry (IHC). In our investigation, FHIT gene alterations in the coding region were detected in 11 of the 63 GBM cases (17.5%). Two different sequence variants were determined: one novel missense variant (G -> C transition at codon 49) and one previously described silent alteration (C -> T transition at codon 88). Using web-based programs, such as SIFT and ESEfinder, it was determined that both alterations might have caused significant modification on protein function. In addition, we identified a previously reported an intronic polymorphism (T -> A transition at IVS8-17) in 47.5% of cases as a similar rate (45%) in the control group. Moreover, it was observed that Fhit protein expression was reduced in 87.5% of tumors. In conclusion, the reduction or loss of Fhit protein expression by genetic alterations or epigenetic mechanisms in GBM might be associated with brain tumorigenesis.

Background Acquired resistance towards apoptosis is a hallmark of cancer. Elimination of cells bearing activated oncogenes or stimulation of tumor suppressor mediators may provide a selection pressure to overcome resistance. KC-53 is a novel biyouyanagin analogue known to elicit strong anti-inflammatory and anti-viral activity. The current study was designed to evaluate the anticancer efficacy and molecular mechanisms of KC-53 against human cancer cells. Methods Using the MTT assay we examined initially how KC-53 affects the proliferation rates of thirteen representative human cancer cell lines in comparison to normal peripheral blood mononuclear cells (PBMCs) and immortalized cell lines. To decipher the key molecular events underlying its mode of action we selected the human promyelocytic leukemia HL-60 and the acute lymphocytic leukemia CCRF/CEM cell lines that were found to be the most sensitive to the antiproliferative effects of KC-53. Results KC-53 promoted rapidly and irreversibly apoptosis in both leukemia cell lines at relatively low concentrations. Apoptosis was characterized by an increase in membrane-associated TNFR1, activation of Caspase-8 and proteolytic inactivation of the death domain kinase RIP1 indicating that KC-53 induced mainly the extrinsic/death receptor apoptotic pathway. Regardless, induction of the intrinsic/mitochondrial pathway was also achieved by Caspase-8 processing of Bid, activation of Caspase-9 and increased translocation of AIF to the nucleus. FADD protein knockdown restored HL-60 and CCRF/CEM cell viability and completely blocked KC-53-induced apoptosis. Furthermore, KC-53 administration dramatically inhibited TNFα-induced serine phosphorylation on TRAF2 and on IκBα hindering therefore p65/NF-κΒ translocation to nucleus. Reduced transcriptional expression of pro-inflammatory and pro-survival p65 target genes, confirmed that the agent functionally inhibited the transcriptional activity of p65. Conclusions Our findings demonstrate, for the first time, the selective anticancer properties of KC-53 towards leukemic cell lines and provide a detailed understanding of the molecular events underlying its dual anti-proliferative and pro-apoptotic properties. These results provide new insights into the development of innovative and targeted therapies for the treatment of some forms of leukemia. Electronic supplementary material The online version of this article (doi:10.1186/s12885-016-2310-5) contains supplementary material, which is available to authorized users.

Background Many targeted therapies used in the treatment of cancer can lead to the development of xerosis, but the incidence and relative risk of xerosis have not been ascertained. Objective We conducted a systematic review and metaanalysis of clinical trials, to ascertain the incidence and risk of developing xerosis after taking anticancer drugs. Methods The PubMed (1966-October 2013), Web of Science (January 1998-October 2013), and American Society of Clinical Oncology abstracts (2004-2013) databases were searched for clinical trials of 58 targeted agents. Results were calculated using random or fixed effects models. Results The incidences of all- and high-grade xerosis were 17.9% (95% confidence interval [CI]: 15.6-20.4%) and 1.0% (95% CI: 0.9-1.5%), respectively. The risk of developing all-grade xerosis was 2.99 (95% CI: 2.0-4.3), and it varied across different drugs (P less than .001). Limitations The reporting of xerosis may vary among clinicians and institutions, and the incidence may be affected by age, concomitant medications, comorbidities, and underlying malignancies or skin conditions. Conclusion Patients receiving targeted therapies have a significant risk of developing xerosis. Patients should be counseled and treated early for this symptom to prevent suboptimal dosing and quality of life impairment.

Amaç: Bu çalışmanın amacı yeni bitkisel bir ürün olan KL-21’in [naturin doğal ürünler şirketi (İzmir, Türkiye) tarafından üretilen] 232B4 kronik lenfostik lösemi (KLL) hücreleri üzerindeki sitotoksik ve apoptotik etkilerinin araştırılmasıdır. Ayrıca, KL-21’in BEAS-2B sağlıklı insan bronşial epitelyum hücreleri üzerindeki sitotoksik etkisine de bakılmıştır. Gereç ve Yöntemler: KL-21’in sitotoksik etkisine MTT hücre çoğalma testiyle bakılmıştır. Kaspaz-3 enzim aktivitesindeki ve mitokondri membran potansiyelindeki değişimlere sırasıyla kaspaz-3 kolorimetrik testi ve JC-1 boyasına dayalı bir yöntem kullanılarak bakılmıştır. Apoptotik hücre popülasyonunu belirlemek amacıyla Anneksin 5-FITC/PI ikili boyama yöntemi kullanılmıştır. KL-21’in KLL hücrelerinin hücre siklusu üzerindeki etkilerine akım sitometresi ile bakılmıştır. Bulgular: KL-21’in KLL hücrelerinin çoğalması üzerine etkisi zamana ve doza bağımlı olarak artmıştır. Bununlar beraber, KL- 21’in özellikle yüksek konsantrasyonlarda KLL hücreleri ile karşılaştırıldığında BEAS-2B hücreleri üzerinde daha az sitotoksik etki gösterdiği saptanmıştır. Anneksin-5/PI ikili boyaması 232B4 hücrelerinde apoptotik hücre popülasyonunun arttığını göstermiştir. KL-21’in artan konsantrayonları kaspaz-3 enzim aktivitesini arttırmış ve mitokondri membran potansiyelindeki kayıpları indüklemiştir. KL-21 1 mg/ml konsantrasyonuna kadar G0/G1 fazındaki hücrelerin yüzdesinde küçük artışlara ve S fazındaki hücre popülasyonunda ise azalmalara neden olmaktadır. En yüksek konsantrasyonda ise hücrelerin büyük bir çoğunluğu G0/G1 fazında birikmiştir. Sonuç: Elde edilen sonuçlar, KL-21’in 232B4 KLL hücreleri üzerinde büyümeyi inhibe edici bir etkisi olduğunu göstermiştir. Ayrıca, K-21 apoptozu indüklemekte ve G0/G1 fazında hücre siklusunun tutulumuna neden olmaktadır., Objective: The aims of this study were to examine the cytotoxic and apoptotic effects of KL-21, a novel plant product (produced by naturin natural Products, İzmir, Turkey), on 232B4 chronic lymphocytic leukemia (CLL) cells and to determine the cytotoxic effects on healthy BEAS-2B human bronchial epithelial cells. Materials and Methods: The cytotoxic effect of KL-21 was determined by MTT cell proliferation assay. Changes in caspase-3 enzyme activity were measured using the caspase-3 colorimetric assay. Changes in mitochondrial membrane potential were determined using the J C-1 dye-based method. Annexin V-FITC/PI double staining was performed to measure the apoptotic cell population. Effects of KL-21 on cell cycle profiles of CLL cells were investigated by flow cytometry. Results: We detected time- and concentration-dependent increases in the cytotoxic effect of KL-21 on 232B4 CLL cells. However, we also showed that, especially at higher concentrations, KL-21 was less cytotoxic towards BEAS-2B healthy cells than towards CLL cells. Annexin-V/PI double staining results showed that the apoptotic cell population increased in 232B4 cells. Increasing concentrations of KL-21 increased caspase-3 enzyme activity and induced loss of mitochondrial membrane potential. KL-21 administration resulted in small increases in the percentage of the cells in the G0/G1 phase while it decreased the S phase cell population up to 1 mg/mL. At the highest concentration, most of the cells accumulated in the G0/G1 phase. Conclusion:KL-21 has a growth-inhibitory effect on 232B4 CLL cells. KL-21 causes apoptosis and cell cycle arrest at G0/G1.

Studies on genetic changes underlying prostate cancer and the possible signaling pathways are getting increased day by day, and new treatment methods are being searched for. The aim of the present study is to investigate the effects of ferulic acid (FA), a phenolic compound, on cell cycle, apoptosis, invasion, and colony formation in the PC-3 and LNCaP prostate cancer cells. The effect of FA on cell viability was determined via a 2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT) method. Total RNA was isolated with Tri Reagent. Expression of 84 genes for both cell cycle and apoptosis separately was evaluated by reverse transcriptase PCR (RT-PCR). Protein expressions were evaluated by Western blot analysis. Furthermore, apoptotic effects of FA were observed with terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick end labeling (TUNEL) assay. Effects of FA on cell invasion and colony formation were determined using Matrigel chamber and colony assay, respectively. The half maximal inhibitory concentration (IC50) dose of FA was found to be 300 µM in PC-3 cells and 500 µM in LNCaP cells. According to RT-PCR results, it was observed that FA inhibited cell proliferation by increasing the gene expressions of ATR, ATM, CDKN1A, CDKN1B, E2F4, RB1, and TP53 and decreasing the gene expressions of CCND1, CCND2, CCND3, CDK2, CDK4, and CDK6 in PC-3 cells. On the other hand, it was seen that FA suppressed cell proliferation by increasing in the gene expressions of CASP1, CASP2, CASP8, CYCS, FAS, FASLG, and TRADD and decreasing in the gene expressions of BCL2 and XIAP in LNCaP cells. In this study, protein expression of CDK4 and BCL2 genes significantly decreased in these cells. It could induce apoptosis in PC-3 and LNCaP cells. Also, it was observed that FA suppressed the invasion in PC-3 and LNCaP cells. Moreover, it suppressed the colony formation. In conclusion, it has been observed that FA may lead to cell cycle arrest in PC-3 cells while it may cause apoptosis in LNCaP cells. © 2015, International Society of Oncology and BioMarkers (ISOBM).

Recombinant human erythropoietin (rHuEPO) is an effective treatment for anaemia but concerns that it causes disease progression in cancer patients by activation of EPO receptors (EPOR) in tumour tissue have been controversial and have restricted its clinical use. Initial clinical studies were flawed because they used polyclonal antibodies, later shown to lack specificity for EPOR. Moreover, multiple isoforms of EPOR caused by differential splicing have been reported in cancer cell lines at the mRNA level but investigations of these variants and their potential impact on tumour progression, have been hampered by lack of suitable antibodies. The EpoCan consortium seeks to promote improved pathological testing of EPOR, leading to safer clinical use of rHuEPO, by producing well characterized EPOR antibodies. Using novel genetic and traditional peptide immunization protocols, we have produced mouse and rat monoclonal antibodies, and show that several of these specifically recognize EPOR by Western blot, immunoprecipitation, immunofluorescence, flow cytometry and immunohistochemistry in cell lines and clinical material. Widespread availability of these antibodies should enable the research community to gain a better understanding of the role of EPOR in cancer, and eventually to distinguish patients who can be treated safely by rHuEPO from those at increased risk from treatment.

Diffuse large B-cell lymphoma (DLBCL) is the most common type of non-Hodgkin lymphoma among adults and is characterized by heterogeneous clinical, immunophenotypic, and genetic features. Different mechanisms deregulating cell cycle and apoptosis play a role in the pathogenesis of DLBCL. Growth arrest DNA damage-inducible 45 (GADD45γ) is an important gene family involved in these mechanisms. The aims of this study are to determine the frequency of GADD45γ methylation, to evaluate the correlation between GADD45γ methylation and protein expression, and to investigate the relation between methylation status and clinicopathologic parameters in DLBCL tissues and reactive lymphoid node tissues from patients with reactive lymphoid hyperplasia.Thirty-six tissue samples of DLBCL and 40 nonmalignant reactive lymphoid node tissues were analyzed in this study. Methylation-sensitive high-resolution melting analysis was used for the determination of GADD45γ methylation status. The GADD45γ protein expression was determined by immunohistochemistry.GADD45γ methylation was frequent (50.0%) in DLBCL. It was also significantly higher in advanced-stage tumors compared with early-stage (p=0.041). In contrast, unmethylated GADD45γ was associated with nodal involvement as the primary anatomical site (p=0.040).The results of this study show that, in contrast to solid tumors, the frequency of GADD45γ methylation is higher and this epigenetic alteration of GADD45γ may be associated with progression in DLBCL. In addition, nodal involvement is more likely to be present in patients with unmethylated GADD45γ.Amaç: Diffüz büyük B-hücreli lenfoma (DBBHL) yetişkin bireylerde Hodgkin-dışı lenfomaların en yaygın tipidir ve klinik, immünofenotipik ve genetik özellikler açısından heterojen özellikler taşıması ile karakterizedir. DBBHL patogenezinde hücre döngüsü ve apoptoz regülasyonunu bozan farklı mekanizmalar rol oynamaktadır. Growth arrest DNA damage-inducible 45 (GADD45γ), bu mekanizmalarda yer alan önemli bir gen ailesidir. Bu çalışmanın amaçları DBBHL doku örnekleri ve reaktif lenfoid hiperplazili bireylerin reaktif lenfoid doku örneklerinde GADD45γ metilasyon sıklığını belirlemek, GADD45γ metilasyonu ile protein ekspresyonu arasındaki ilişkiyi değerlendirmek ve DBBHL olgularında metilasyon durumunun klinikopatolojik parametrelerle ilişkisini araştırmaktır. Gereç ve Yöntemler: Bu çalışmada 36 adet DBBHL doku örnekleri ve 40 adet malign-olmayan reaktif lenfoid doku örnekleri analiz edildi. GADD45γ metilasyon durumunu belirlemek için metilasyona-duyarlı yüksek çözünürlüklü erime eğrisi analizi kullanıldı. GADD45γ protein ekspresyonu immünohistokimyasal analiz ile belirlendi. Bulgular: DBBHL’de GADD45γ metilasyonunun sık olduğu belirlendi (%50). Aynı zamanda, erken evre ile karşılaştırıldığında ileri evre tümörlerde GADD45γ metilasyonu istatistiksel olarak anlamlı düzeyde yüksekti (p=0,041). Ancak, GADD45γ metilasyon yokluğunun primer anatomik yerleşim olarak nodal tutulumla ilişkili olduğu belirlendi (p=0,040). Sonuç: Bu çalışmanın sonuçları solid tümörlerin aksine, DBBHL’de GADD45γ metilasyon sıklığının yüksek olduğunu ve GADD45γ geninde gözlenen bu epigenetik değişimin, hastalığın progresyonu ile ilişkili olabileceğini göstermektedir. Buna ek olarak, nodal tutulum daha çok GADD45γ metile olmayan olgularda gözlenmektedir.

Indexación: Web of Science; Scopus. Stem cell phenotypes are reflected by posttranslational histone modifications, and this chromatin-related memory must be mitotically inherited to maintain cell identity through proliferative expansion. In human embryonic stem cells (hESCs), bivalent genes with both activating (H3K4me3) and repressive (H3K27me3) histone modifications are essential to sustain pluripotency. Yet, the molecular mechanisms by which this epigenetic landscape is transferred to progeny cells remain to be established. By mapping genomic enrichment of H3K4me3/H3K27me3 in pure populations of hESCs in G2, mitotic, and G1 phases of the cell cycle, we found striking variations in the levels of H3K4me3 through the G2-M-G1 transition. Analysis of a representative set of bivalent genes revealed that chromatin modifiers involved in H3K4 methylation/demethylation are recruited to bivalent gene promoters in a cell cycle-dependent fashion. Interestingly, bivalent genes enriched with H3K4me3 exclusively during mitosis undergo the strongest upregulation after induction of differentiation. Furthermore, the histone modification signature of genes that remain bivalent in differentiated cells resolves into a cell cycle-independent pattern after lineage commitment. These results establish a new dimension of chromatin regulation important in the maintenance of pluripotency http://mcb.asm.org/content/36/4/615

Transcription factor Snail mediates epithelial to mesenchymal transitions (EMT) by coordinate repression of epithelial markers, facilitating mass cell movement during germ layer formation. Aberrant reprogramming in its signaling pathways causes metastatic cancer. Snail's involvement in "fate-changing" decisions is however not understood. Cripto-1 shares a common temporal expression pattern with Snail during development. While Cripto-1 is required for mammary morphogenesis and hematopoietic stem cell renewal, its unregulated expression causes metastatic cancers. Therefore, we suspected that Snail regulates the expression of Cripto-1 controlling decisions such as motility, transformation and differentiation. We demonstrate that Snail represses Cripto-1 gene by direct transcriptional interaction and propose a novel mechanism by which it co-ordinately regulates cell fate decisions during development and could be causal of cancers. � 2015 Federation of European Biochemical Societies.

Valproic acid (VPA), used for the treatment of epilepsy and bipolar disorder, regulates several signaling pathways in brain cells. The up-regulated gene 4 (URG4/URGCP) is a novel gene located on 7p13. URG4/URGCP stimulates cyclin D1 (CCND1) mRNA expression, and URG4/URGCP silencing diminishes CCND1 mRNA expression in HepG2 cells. This study was performed to investigate the anti-cancer mechanism of action of VPA by analyzing the expression of novel gene URG4/URGCP, CCND1, p21, p53, p65 (RelA), Bax, and Bcl-2 in SHSY5Y neuroblastoma (NB) cancer cells. Cytotoxic effects of VPA in SHSY5Y were noticed in time and dose dependent manner with the IC50 doses within the range of 0.5-10 mM. IC50 doses in the SHSY5Y were detected as 7.5 mM. Expression profiles were determined by semi quantitative RT-PCR and URG4/URGCP protein change by western blot analysis. Our results suggest that VPA induces cell cycle arrest in SHSY5Y due to the decrease in URG4/URGCP, CCND1 gene expression and the increase in p65. To conclude, VPA may be a prospective agent for the treatment of NB as a single agent or in combination with other drugs. Thus, more studies should be designed to find a safe dose with the best effects of VPA. © 2014 Springer Science+Business Media.

Hepatocellular carcinoma (HCC) originates from liver cells and is one of the most common malignant cancers in the world. microRNAs (miRNA), are single strand non-coding RNA molecules with the length of 18-25 nucleotides. miRNAs play an important role in the development of HCC, i.e., miRNAs have a significant impact on multistep hepatocellular carcinogenesis including cellular migration and invasion. URG4/URGCP (up-regulated gene-4/upregulator of cell proliferation) is up-regulated in the presence of HBxAg and has been identified and characterized by Satiroglu-Tufan et al. The full-length URG4/URGCP is 3.607 kb. Overexpression of URG4/URGCP in the presence of HBV X protein may function as a putative oncogene that significantly contributes to multi-step hepatocarcinogenesis. In this study, we aimed to investigate potential miRNA expression changes in HepG2 cell line model system in the presence of URG4/URGCP and in the absence of URG4/URGCP, which was suppressed by RNA interference. To functionally characterize URG4/URGCP, independent cultures of HepG2 cells were stably transfected with pcDNA3 or pcDNA3-URG4/URGCP. Relative quantification of whole genome miRNAs was analyzed by RT-PCR using human whole genome miRNA qPCR profiling kits. Among the 1,034 human miRNAs investigated by the arrays, 77 miRNAs were up-regulated and nine miRNAs were down-regulated in the presence of URG4/URGCP. In conclusion, we have analyzed miRNA profiles in HepG2 cells in presence or absence of URG4/URGCP gene using RNA interference. Some of these miRNAs may play roles in URG4/URGCP gene related disease development through the regulation of different signaling pathways. © 2012 Springer Science+Business Media Dordrecht.

Molecular targets in prostate cancer are continually being explored, for which there are currently few therapeutic options. Rapamycin (RPM) is an antifungal macrolide antibiotic isolated from Streptomyces hygroscopicus which can inhibit the G1 to S transition. URGCP (upregulator of cell proliferation) is a novel gene located on chromosome 7p13. We aimed to investigate the role of URGCP gene expression changes in PC3, DU145, and LNCAP cell lines with/out RPM. Average cell viability and cytotoxic effect of rapamycin were investigated at 24 h intervals for three days by using Trypan blue dye exclusion test and XTT assay. Cytotoxic effects of rapamycin in DU145, PC3 and LNCAP cells were detected in time and dose dependent manner with the IC(50) doses within the range of 1-100 nM. As the results were evaluated, IC(50) doses in the DU145, PC3, and LNCaP cells were detected as 10, 25, and 50 nM, respectively. The mean relative ratios of URGCP gene expression in DU145, LNCAP and PC3 cells were found as -1.48, 6.59 and -13.00, respectively, when compared to rapamycin-free cells. The False Discovery Rate adjusted p value in DU145, LNCAP and PC3 were 1.25 × 10(-5), 2.20 × 10(-8) and 6.20 × 10(-9), respectively. When the URGCP gene expression level is compared between the dose and control group, we found that URGCP gene expression was significantly decreased in dose groups of DU145 and PC3 cells.

Up-regulated gene 4 (URG4), stimulated by HBxAg, is a novel gene located on chromosome 7 (7p13). The full-length URG4 clone is 3.607 kb and encodes a polypeptide of 922 amino acids, with a molecular weight of 104 kDa (GeneID: 55665). It promotes cell growth, growth factor-independent survival, and anchorage-independent growth in HepG2 cells, and it accelerates tumor formation in nude mice. Hence, URG4 may be a natural effector of HBxAg and a putative oncogene that contributes to multi-step hepatocarcinogenesis. Cyclin D1 is frequently over-expressed in hepatocellular carcinoma, exhibiting a number of malignant phenotypes. We found that down-regulation of URG4 through RNA interference-mediated silencing suppressed cell proliferation in HepG2 cells. Over-expression of URG4 up-regulated cyclin D1 mRNA expression, whereas RNA interference-mediated URG4 silencing diminished cyclin D1 mRNA expression in HepG2 cells. The data suggest that URG4 may play an important role in the development of hepatocellular carcinoma by partially regulating the expression of cyclin D1 and has potential for use as a therapeutic target for hepatocellular carcinoma.

Leukocyte adhesion deficiency (LAD)-III is associated with homozygous stop codon mutations in Kindlin-3, the hematopoietic member of the Kindlin family of integrin coactivators. In addition, a subgroup of LAD-III patients has a homozygous splice junction mutation in and reduced expression of the Rap-1 guanine nucleotide exchange factor, CalDAG-GEFI (CDGI). In this study, we compared the adhesive properties of the leukocyte function-associated antigen-1 (LFA-1) and very late activation antigen-4 (VLA-4) integrins in both primary and activated leukocytes derived from these 2 LAD-III subgroups. Primary lymphocytes lacking both Kindlin-3 and CDGI lost all firm T-cell receptor-stimulated LFA-1 adhesiveness, in contrast to LAD-III lymphocytes deficient in Kindlin-3 alone. Effector T cells expanded from all tested LAD-III variants expressed normal CDGI, but lacked Kindlin-3. These Kindlin-3-null effector T cells exhibited total loss of inside-out LFA-1 activation by chemokine signals as well as abrogated intrinsic LFA-1 adhesiveness. Surprisingly, VLA-4 in Kindlin-3-null resting or effector lymphocytes retained intrinsic rolling adhesions to vascular cell adhesion molecule-1 and exhibited only partial defects in chemokine-stimulated adhesiveness to vascular cell adhesion molecule-1. Deletion of the putative beta(1) Kindlin-3 binding site also retained VLA-4 adhesiveness. Thus, our study provides the first evidence that Kindlin-3 is more critical to LFA-1 than to VLA-4-adhesive functions in human lymphocytes. Israel Science Foundation US-Israel Binational Science Foundation Minerva Foundation, Germany

Background: In the present study, we demonstrate, in rigorous fashion, that human monocyte-derived immature dendritic cells (DCs) can efficiently cross-present tumor-associated antigens when co-cultured with a mixture of human melanoma cells rendered apoptotic/necrotic by γ irradiation (Apo-Nec cells). Methods: We evaluated the phagocytosis of Apo-Nec cells by FACS after PKH26 and PKH67 staining of DCs and Apo-Nec cells at different times of coculture. The kinetics of the process was also followed by electron microscopy. DCs maturation was also studied monitoring the expression of specific markers, migration towards specific chemokines and the ability to cross-present in vitro the native melanoma-associated Ags MelanA/MART-1 and gp100. Results: Apo-Nec cells were efficiently phagocytosed by immature DCs (iDC) (55 ± 10.5%) at 12 hs of coculture. By 12-24 hs we observed digested Apo-Nec cells inside DCs and large empty vacuoles as part of the cellular processing. Loading with Apo-Nec cells induced DCs maturation to levels achieved using LPS treatment, as measured by: i) the decrease in FITC - Dextran uptake (iDC: 81 ± 5%; DC/Apo-Nec 33 ± 12%); ii) the cell surface up-regulation of CD80, CD86, CD83, CCR7, CD40, HLA-I and HLA-II and iii) an increased in vitro migration towards MIP-3β. DC/Apo-Nec isolated from HLA-A*0201 donors were able to induce >600 pg/ml IFN-γ secretion of CTL clones specific for MelanA/MART-1 and gp100 Ags after 6 hs and up to 48 hs of coculture, demonstrating efficient cross-presentation of the native Ags. Intracellular IL-12 was detected in DC/Apo-Nec 24 hs post-coculture while IL-10 did not change. Conclusion: We conclude thatthe use of a mixture of four apoptotic/ necrotic melanoma cell lines is a suitable source of native melanoma Ags that provides maturation signals for DCs, increases migration to MIP-3β and allows Ag cross-presentation. This strategy could be exploited for vaccination of melanoma patients. © 2007 von Euw et al; licensee BioMed Central Ltd. Fil:von Euw, E.M. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Barrio, M.M. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Levy, E.M. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.

Here, we describe a proteomics approach to study protein expression changes in differentiating Caco-2 cells. Caco-2 is a colorectal carcinoma cell line, which upon differentiation loses its tumorigenic phenotype and displays characteristics of mature enterocytes, including brush borders with microvilli. Cells were grown in culture flasks and harvested at different stages of differentiation (days post-confluence: -3, 0, 3, 7, 10, 14, and 18). Two-dimensional gel electrophoresis was used to analyse proteome changes. Approximately 1400 protein spots were detected within the Caco-2 proteome, within the pH 4-7 range. Two-dimensional gel electrophoresis allowed for the detection of 18 proteins from which the levels of expression were found to be associated with differentiation. Of these proteins, 11 were identified by means of MALDI-TOF or NANO-ESI-MS/MS mass spectrometry and include liver fatty acid binding protein (FABL), three forms of α-enolase (ENOA), nucleoside diphosphate kinase A (NDKA), cofilin-1 (COF1), translationally controlled tumour protein (TCTP), mitochondrial 60-kDa heat shock protein (CH60), probable protein disulfide isomerase (ER60), creatine kinase B (KCRB), and glutathione S-transferase α (GTA1). Thus, proteomics revealed that the differentiation-related change in phenotype of Caco-2 involves changes in a variety of distinct biochemical pathways. Some of these proteins have not been shown before to be associated with Caco-2 differentiation (ER60; COF1; CH60; NDKA; TCTP and ENOA). Therefore, processes related to protein folding and disulfide bridge formation, cytoskeleton formation and maintenance, nucleotide metabolism, glycolysis as well as tumorigenesis-associated proteins may be involved in Caco-2 differentiation. Changes in the expression of CH60, TCTP, GTA1, NDKA, and FABL have also been reported to be associated with in vivo colon carcinogenesis. These findings illustrate that a combination of proteomics and cell culture is a useful approach to find markers for Caco-2 differentiation, which could contribute to the comprehension of the process of colon carcinogenesis. © 2003 Elsevier B.V. All rights reserved.

Here, we describe a proteomics approach to study protein expression changes in differentiating Caco-2 cells. Caco-2 is a colorectal carcinoma cell line, which upon differentiation loses its tumorigenic phenotype and displays characteristics of mature enterocytes, including brush borders with microvilli. Cells were grown in culture flasks and harvested at different stages of differentiation (days post-confluence: -3, 0, 3, 7, 10, 14, and 18). Two-dimensional gel electrophoresis was used to analyse proteome changes. Approximately 1400 protein spots were detected within the Caco-2 proteome, within the pH 4-7 range. Two-dimensional gel electrophoresis allowed for the detection of 18 proteins from which the levels of expression were found to be associated with differentiation. Of these proteins, 11 were identified by means of MALDI-TOF or NANO-ESI-MS/MS mass spectrometry and include liver fatty acid binding protein (FABL), three forms of α-enolase (ENOA), nucleoside diphosphate kinase A (NDKA), cofilin-1 (COF1), translationally controlled tumour protein (TCTP), mitochondrial 60-kDa heat shock protein (CH60), probable protein disulfide isomerase (ER60), creatine kinase B (KCRB), and glutathione S-transferase α (GTA1). Thus, proteomics revealed that the differentiation-related change in phenotype of Caco-2 involves changes in a variety of distinct biochemical pathways. Some of these proteins have not been shown before to be associated with Caco-2 differentiation (ER60; COF1; CH60; NDKA; TCTP and ENOA). Therefore, processes related to protein folding and disulfide bridge formation, cytoskeleton formation and maintenance, nucleotide metabolism, glycolysis as well as tumorigenesis-associated proteins may be involved in Caco-2 differentiation. Changes in the expression of CH60, TCTP, GTA1, NDKA, and FABL have also been reported to be associated with in vivo colon carcinogenesis. These findings illustrate that a combination of proteomics and cell culture is a useful approach to find markers for Caco-2 differentiation, which could contribute to the comprehension of the process of colon carcinogenesis. © 2003 Elsevier B.V. All rights reserved.

Secretory meningiomas are a rare meningioma subtype. Among meningiomas, the frequency of secretory meningiomas is 1.6%. Unlike other meningioma types, most of the patients were female (ratio 3:1). No recurrence was reported during the 24-180 months follow-up period of our secretory meningiomas in which, a low level of 0.3% Ki-67 proliferative index was reported. In this meningioma subtype, the percentage of cases with positive progesterone receptor is 33%. With carcinoembryonic antigen, cytokeratin and epithelial membrane antigen, in all the cases positivity was observed in both, the inclusions and the cells surrounding them. With human milk fat globulin 2, a high ratio (92%) of positivity was observed. Majority of the cases were negative with CA125, only three of the cases had suspicious positivity. Distribution of inclusions was irregular and their positive reactions showed varying staining features. Positivity with alpha-1-antitripsin was seen not only in the inclusions but also in some meningothelial cells as well. Ubiquitin was positive in inclusions of the 83% of cases. Staining features of the inclusions pointed out the possibility of them being in a varying age and/or content. Secretory meningiomas are a different type compared to other meningiomas, not only with their histological features but also with their clinical features as well.

We have studied the biochemical features, the conformational preferences in solution, and the DNA binding properties of human p8 (hp8), a nucleoprotein whose expression is affected during acute pancreatitis. Biochemical studies show that hp8 has properties of the high mobility group proteins, HMG-I/Y. Structural studies have been carried out by using circular dichroism (near- and far-ultraviolet), Fourier transform infrared, and NMR spectroscopies. All the biophysical probes indicate that hp8 is monomeric (up to 1 mM concentration) and partially unfolded in solution. The protein seems to bind DNA weakly, as shown by electrophoretic gel shift studies. On the other hand, hp8 is a substrate for protein kinase A (PKA). The phosphorylated hp8 (PKAhp8) has a higher content of secondary structure than the nonphosphorylated protein, as concluded by Fourier transform infrared studies. PKAhp8 binds DNA strongly, as shown by the changes in circular dichroism spectra, and gel shift analysis. Thus, although there is not a high sequence homology with HMG-I/Y proteins, hp8 can be considered as a HMG-I/Y-like protein. Fil:Mallo, G.V. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Mizyrycki, C. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Giono, L. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Cánepa, E. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Moreno, S. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.

Hereditary non-polyposis colon cancer (HNPCC) is a common hereditary disease characterized by a predisposition to an early onset of colorectal cancer. The majority of the HNPCC families carry germline mutations of either hMSH2 or hMLH1 genes, whereas germline mutations of hPMS1 and hPMS2 genes have rarely been observed. Almost all of the germline mutations reported so far concern typical HNPCC families. However, there are families that display aggregations of colon cancer even though they do not fulfil all HNPCC criteria (incomplete HNPCC families) as well as sporadic cases of early onset colon cancers that could be related to germline mutations of these genes. Therefore, we screened germline mutations of hMSH2 and hMLH1 genes in 3 groups of patients from France and Turkey: typical HNPCC (n = 3), incomplete HNPCC (n = 9) and young patients without apparent familial history (n = 7). By in vitro synthesis of protein assay, heteroduplex analysis and direct genomic sequencing, we identified 1 family with hMSH2 mutation and 5 families with hMLH1 mutations. Two of the 3 HNPCC families (66%) displayed hMLH1 germline mutations. Interestingly, 4 of 9 families with incomplete HNPCC (44%) also displayed mutations of hMSH2 or hMLH1 genes. In contrast, no germline mutation of these genes was found in 7 young patients. Our results show that germline mutations of hMSH2 and hMLH1 genes contribute to a significant fraction of familial predisposition to colon cancer cases that do not fulfil all diagnostic criteria of HNPCC. © 1997 Wiley-Liss, Inc.

Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-27T10:59:38Z No. of bitstreams: 0Bitstream added on 2014-05-27T14:28:07Z : No. of bitstreams: 1 2-s2.0-0025654220.pdf: 458884 bytes, checksum: faa27c861fa1e802602345f6250d5148 (MD5) Made available in DSpace on 2014-05-27T10:59:38Z (GMT). No. of bitstreams: 0 Previous issue date: 1990-12-01 Two cases of polymorphous low-grade adenocarcinoma of the papillary type, from minor salivary glands were studied by light microscopy and immunohistochemistry. One case exhibited a predominance of the papillary pattern, whereas the other presented the following patterns of histological appearance: papillary, solid, pseudocystic and tubular. Utilizing the peroxidase-antiperoxidase (PAP) method, the intermediate filament vimentin, keratin and S100 protein were observed in tumor cells. The immunohistochemical analysis revealed two types of neoplastic cells: myoepithelial and luminal.

Assessment of chemosensitivity of neovessel endo-thelium associated to tumor mass is hindered by the limited availability of experimental models of actively proliferating endothelial cells. In fact, primary endothelial cells possess a limited lifespan and replicative senescence represents a major limit to their long-term culture. Moreover, non-dividing senescent cells undergo a gradual loss of phenotypic markers and become unable to respond to mitogenic stimuli. We report the generation of an immortalized human endothelial cell line by transfection of human umbilical vein endothelial cells (HUVEC) with both SV40 large/small T antigens and the catalytic subunit of human telomerase. This cell line (HUV-ST) possesses stabilized telomere length and increased proliferation rate with respect to parental cells or to cells transfected with SV40 T antigens only (HUV-S). Nevertheless, even at PD > 100 it is not tumorigenic and displays all major endothelial phenotypic markers, such as von Willebrand factor, CD31, vascular endothelial growth factor (VEGF) receptors (VEGFR1/Flt-1, VEGR2/KDR) and CD105/endoglin. HUV-ST cells are capable of organizing into tubule-like networks with branching morphology in response to appropriate stimuli and migrate upon exposure to VEGF. Interestingly, HUV-ST cells over-express the tumor endothelial marker-1/endosialin which is regarded as the most differentially expressed molecule in tumor-derived endothelium versus normal-derived endothelium. Analysis of chemosensitivity to the wide spectrum methylating agent temozolomide (TMZ), an anticancer drug more effective against actively dividing cells than against resting or slowing proliferating cells, indicated that HUV-ST cells are more susceptible to the drug with respect to HUVEC or HUV-S cells. Abrogation of poly(ADP-ribose) polymerase activity significantly enhances growth inhibition induced by TMZ. In conclusion, the immortalized human endothelial line HUV-ST represents a suitable model for studying the efficacy of anti-neovascular therapy, mimicking proliferating neovascular endothelial cells associated to the tumor mass.