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Treatment of prostate cancer (PC) by androgen suppression promotes the emergence of aggressive variants that are androgen receptor (AR) independent. Here we identify the transcription factor ONECUT2 (OC2) as a master regulator of AR networks in metastatic castration-resistant prostate cancer (mCRPC). OC2 acts as a survival factor in mCRPC models, suppresses the AR transcriptional program by direct regulation of AR target genes and the AR licensing factor FOXA1, and activates genes associated with neural differentiation and progression to lethal disease. OC2 appears active in a substantial subset of human prostate adenocarcinoma and neuroendocrine tumors. Inhibition of OC2 by a newly identified small molecule suppresses metastasis in mice. These findings suggest that OC2 displaces AR-dependent growth and survival mechanisms in many cases where AR remains expressed, but where its activity is bypassed. OC2 is also a potential drug target in the metastatic phase of aggressive PC.

Response to the oncology drug gemcitabine may be variable in part due to genetic differences in the enzymes and transporters responsible for its metabolism and disposition. The aim of our in-silico study was to identify gene variants significantly associated with gemcitabine response that may help to personalize treatment in the clinic.

As histone deacetylase inhibitors such as romidepsin (depsipeptide, FK228) complete successful Phase I clinical trials in pediatric solid tumors, it is important that their mechanisms of action are delineated in order to inform the development of subsequent clinical trials as single agents or in combination therapies. In this study, we evaluate the effect of romidepsin as a single agent on a number of different neuroblastoma (NB) cell lines. We find that the growth of 6/6 human NB tumor cell lines but not an immortalized fibroblast cell line (NIH3T3) is inhibited by romidepsin (IC50 = 1-6.5 ng/ml) after 72 h of treatment. Romidepsin shows selective dose-dependent cytotoxicity in both single copy and N-myc amplified NB cell lines, in cell lines with wild-type or mutant p53 and those containing Alk mutations. The decrease in cell proliferation is accompanied by caspase-dependent apoptosis as shown by PARP cleavage, an accumulation of cells in the sub-G1 phase of the cell cycle and the ability of a pan-caspase inhibitor to reduce cell death. Romidepsin inhibits the growth of subcutaneous NB xenografts in a dose dependent manner in immunocompromised mice. Furthermore, romidepsin induces expression of genes such as p21 and expression of p75 and NTRK (TrkA) which are more highly expressed in the tumors from NB patients that have a good prognosis. These studies support continued investigations into the therapeutic activity of romidepsin in NB.

ABCG2 is an ATP-binding cassette transporter that counts multiple anticancer compounds among its substrates and is believed to regulate oral bioavailability as well as serve a protective role in the blood-brain barrier, the maternal-fetal barrier, and hematopoietic stem cells. We sought to determine whether novel compounds that interact with the transporter could be identified through analysis of cytotoxicity profiles recorded in the NCI Anticancer Drug Screen database. A flow cytometric assay was used to measure ABCG2 function in the 60 cell lines and generate a molecular profile for COMPARE analysis. This strategy identified >70 compounds with Pearson correlation coefficients (PCCs) >0.4, where reduced drug sensitivity correlated with ABCG2 expression, as well as >120 compounds with PCCs < –0.4, indicating compounds to which ABCG2 expression conferred greater sensitivity. Despite identification of known single nucleotide polymorphisms in the ABCG2 gene in a number of the cell lines, omission of these lines from the COMPARE analysis did not affect PCCs. Available compounds were subjected to validation studies to confirm interaction with the transporter, including flow cytometry, [125I]IAAP binding, and cytotoxicity assays, and interaction was documented in 20 of the 27 compounds studied. Although known substrates of ABCG2 such as mitoxantrone or topotecan were not identified, we characterized three novel substrates—5-hydroxypicolinaldehyde thiosemicarbazone (NSC107392), (E)-N-(1-decylsulfanyl-3-hydroxypropan-2-yl)-3-(6-methyl-2,4-dioxo-1H-pyrimidin-5-yl)prop-2-enamide (NSC265473), and 1,2,3,4,7-pentahydroxy-1,3,4,4a,5,11b-hexahydro[1,3]dioxolo[4,5-j]phenanthridin-6(2H)-one [NSC349156 (pancratistatin)]—and four compounds that inhibited transporter function—2-[methyl(2-pyridin-2-ylethyl)-amino]fluoren-9-one hydroiodide (NSC24048), 5-amino-6-(7-amino-5,8-dihydro-6-methoxy-5,8-dioxo-2-quinolinyl)-4-(2-hydroxy-3,4-dimethoxyphenyl)-3-methyl-2-pyridinecarboxylic acid, methyl ester (NSC45384), (17β)-2,4-dibromo-estra-1,3,5(10)-triene-3,17-diol (NSC103054), and methyl N-(pyridine-4-carbonylamino)carbamodithioate (NSC636795). In summary, COMPARE analysis of the NCI drug screen database using the ABCG2 functional profile was able to identify novel substrates and transporter-interacting compounds.

Cancers arising in pancreas, lung, liver, and stomach are difficult to treat successfully. Wanting to understand the basis for such intractability, we previously performed comparative analyses of publicly available gene expression data from tumor biopsies. Expression of many cell adhesion genes correlated significantly with intractability of cancers, our surrogate of intractability being the SEER five-year survivals of patients with disseminated tumors. To model resistance mediated by cell adhesion, we evaluated HCT 116 cells grown in two modes differing in cell adhesion status : (i) as monolayers attached to plastic culture dishes, (ii) cells attached to one another in spheroids. We determined gene expression profiles of cells grown in these two modes, for three or six days, using the human genome U133A microarray (Affymetrix, Inc.). There was a striking overlap between (a) the genes expressed differentially between early monolayers and early spheroids and (b) those expressed differentially between early and confluent monolayers. However, there was no similarity between these overlaps and the genes that were differentially expressed in intractable, as opposed to more tractable, tumors. We hypothesize that the cytotoxicity resistance for polyHEMA spheroids and for confluent cells have a similar basis, one that differs from the resistance found in intractable solid tumors in patients. Cytotoxicity, cell cycle and immunohistochemistry assays on early and on confluent monolayers, and on spheroids, showed similarities between these latter two conditions. We conclude that while spheroids (and confluent monolayer cells) show drug resistance, the mechanisms underlying this resistance diverge from those conferring resistance to intractable cancers.

In photodynamic therapy (PDT), a tumor-selective photosensitizer is administered after which the photosensitizer is activated by exposure to a light source of a given wavelength. This, in turn, generates reactive oxygen species that induce cellular apoptosis and necrosis in tumor tissue. Based on our earlier finding that the photosensitizer pheophorbide a is an ABCG2 substrate, we explored the ability of ABCG2 to transport photosensitizers with a structure similar to that of pheophorbide a. ABCG2-overexpressing NCI-H1650 MX50 bronchoalveolar carcinoma cells were found to have reduced intracellular accumulation of pyropheophorbide a methyl ester and chlorin e6 compared to parental cells as measured by flow cytometry. The ABCG2 inhibitor fumitremorgin C was found to abrogate ABCG2-mediated transport. Intracellular fluorescence of hematoporphyrin IX, meso-tetra(3- hydroxyphenyl)porphyrin, and meso-tetra(3-hydroxyphenyl)chlorin was not substantially affected by ABCG2. ABCG2-overexpressing cells also displayed decreased intracellular fluorescence of protoporphyrin IX generated by exogenous application of 5-aminolevulinic acid. Mutations at amino acid 482 in the ABCG2 protein known to affect substrate specificity were not found to impact transport of the photosensitizers. In cytotoxicity assays, ABCG2-transfected HEK-293 cells were 11-fold, 30-fold, 4-fold, and >7-fold resistant to PDT with pheophorbide a, pyropheophorbide a methyl ester, chlorin e6, and ALA, respectively. ABCG2- transfected cells were not resistant to PDT with meso-tetra(3-hydroxyphenyl) chlorin. Neither MRP1 expression nor Pgp expression appreciably decreased the intracellular fluorescence of any of the photosensitizers as measured by flow cytometry. The results presented here implicate ABCG2 as a possible cause for cellular resistance to photodynamic therapy.

A 4 year survey of a low socioeconomic prenatal population in a large outpatient clinic revealed an incidence of 4.4 gonorrhea by cervical culture. These patients who were culture-positive had a 7.6 perinatal mortality rate compared to a 3.0 perinatal mortality rate among culture-negative patients from the same clinic. The immaturity and prematurity rate was significantly higher in the culture-positive group as was the incidence of premature rupture of the membranes and prolonged premature rupture of membranes.

ALPS is an inherited disorder of apoptosis leading to lymphoproliferation and autoimmunity. ALPS Type Ia, Ib and II are associated with germline mutations in Fas, FasL and Casapase 8 or 10, respectively; patients in whom no mutations have been identified are classified as Type III. The vast majority of patients are ALPS Type Ia (greater than 70%). They often present with childhood onset autoimmune cytopenias associated with lymphadenopathy, splenomegaly, increased double negative T cells (DNT; TCRa/ß+CD3+CD4-CD8-), defective apoptosis by in vitro assay, and have an increased risk of lymphoma. Similarly, MRL/lpr-/- mice homozygous for Fas mutations develop an ALPS-like disease with massive lymphadenopathy, splenomegaly, hypergammaglobulinemia, autoimmune glomerulonephritis, and expansion of DNT cells secondary to defective lymphocyte apoptosis leading to lymphomagenesis. Currently, there are no proven therapies for the lymphoproliferation underlying ALPS itself, although complications like autoimmune cytopenias and post-splenectomy sepsis are manageable. Hence, studies were conducted to determine the efficacy of valproic acid (VPA) to control the lymphoproliferation associated with ALPS. VPA is a histone deacetylase (HDAC) inhibitor in clinical use for the last four decades as an anticonvulsant in children and adults, and recently being explored as an anti-neoplastic agent. PBMCs from normal controls and ALPS Type Ia patients were cultured in vitro with 0–4 mM VPA in the presence or absence of 50 uM of the pan-caspase inhibitor Z-VAD-FMK. A dose response was observed with a high degree of cell death noted at 4 mM after 48 hours, with an LD50 of 2 mM. VPA appeared to induce cell death by both caspase-dependent and -independent mechanisms based on partial inhibition of VPA-induced cell death by Z-VAD-FMK. Further preclinical studies were conducted in the MRL/lpr-/- murine model of ALPS. Twenty, 8-week old female MRL/lpr-/- mice were treated intraperitoneally (i.p.) with 500 mg/kg of VPA in sterile PBS or PBS alone five days per week for 8 weeks. Significant reduction of the spleen weight (p=0.034) and cellularity (p=0.0001) was observed in VPA treated (n=10) mice compared to controls (n=10). Reductions in size and cellularity were also observed in the lymph nodes (p=0.09 and 0.0002, respectively). A concomitant decrease (p<0.05) in DNT cells was observed in the spleen (11.2±0.6 vs 8.1±0.4) and blood (9.3±0.96 vs 5.5±0.6). Serum drug levels peaked (462±10 ug/mL) by 2 hours post-i.p. injection of VPA, where-as a 2.5 fold increase in histone acetylation was observed in the spleen at 4 hours, following a single injection. Analysis of the effects of VPA on autoimmune renal disease in these animals is underway. Based on our in vitro and in vivo data, VPA is effective at reducing lymphoproliferative activity in Fas deficient MRL/lpr-/- mice. It is being further explored in early phase clinical trials as a lympholytic agent to shrink lymph nodes and abrogate hypersplenism in ALPS patients.

Discusses the development by the US Army of full divisional operations for the early 21st century. Focus on power projection and advances in technology; Capability of deploying forces from the United States to regional conflicts; Transformation of the battlefield due to advances in technology.

Assesses the capability and readiness of Russia's armed forces. Redeployment, reorganization and reductions of armed forces; Declaration of ownership of best military equipments by Ukraine and Belarus.