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Prostate cancer is the most common cancer among men and has a high incidence and associated mortality worldwide. It is an androgen-driven disease in which tumor growth is triggered via ligand-mediated signaling through the androgen receptor (AR). Recent evidence suggests that the widespread use of effective AR pathway inhibitors may increase the occurrence of neuroendocrine prostate cancer (NEPC), an aggressive and treatment-resistant AR-negative variant; however, mechanisms controlling NEPC development remain to be elucidated. Various preclinical models have recently been developed to investigate the mechanisms driving the NEPC differentiation. In the present study, we summarized strategies for the development of NEPC models and proposed a novel method for model evaluation, which will help in the timely and accurate identification of NEPC by virtue of its ability to recapitulate the heterogeneity of prostate cancer. Moreover, we discuss the origin and the mechanism of NEPC. The understanding of the regulatory network mediating neuroendocrine differentiation presented in this review could provide valuable insights into the identification of novel drug targets for NEPC as well as into the causes of antiandrogenic drug resistance.

supplemental figure legends

S1: RNAi mediated dose dependent mRNA silencing in human CRC xenografts. S2: Biodistribution and informal tolerability of DCR-BCAT in wild type mice. S3: Trametinib efficacy in human CRCs.

Legends for supplementary figures

Colorectal carcinomas harbor well-defined genetic abnormalities, including aberrant activation of Wnt/β-catenin and MAPK pathways, often simultaneously. Although the MAPK pathway can be targeted using potent small-molecule drugs, including BRAF and MEK inhibitors, β-catenin inhibition has been historically challenging. RNAi approaches have advanced to the stage of clinical viability and are especially well suited for transcriptional modulators, such as β-catenin. In this study, we report therapeutic effects of combined targeting of these pathways with pharmacologic agents. Using a recently described tumor-selective nanoparticle containing a β-catenin–targeting RNAi trigger, in combination with the FDA-approved MEK inhibitor (MEKi) trametinib, we demonstrate synergistic tumor growth inhibition in in vivo models of colorectal cancer, melanoma, and hepatocellular carcinoma. At dose levels that were insufficient to significantly impact tumor growth as monotherapies, combination regimens resulted in synergistic efficacy and complete tumor growth inhibition. Importantly, dual MEKi/RNAi therapy dramatically improved survival of mice bearing colorectal cancer liver metastases. In addition, pharmacologic silencing of β-catenin mRNA was effective against tumors that are inherently resistant or that acquire drug-induced resistance to trametinib. These results provide a strong rationale for clinical evaluation of this dual-targeting approach for cancers harboring Wnt/β-catenin and MAPK pathway mutations. Mol Cancer Ther; 17(2); 544–53. ©2017 AACR.

Figure S1. Components of EnCore-A; Figure S2. Silencing of CTNNB1 mRNA after single-dose or multiple-dose regimens; Figure S3: Comparable activity achieved with a payload with 2'F modifications; Figure S4. Tumor growth inhibition in multiple subcutaneous xenograft models; Figure S5. No efficacy observed in APC/CTNNB1 wild-type RKO tumors; Figure S6. ApoE-independent DsiRNA delivery to primary and metastatic tumors; Figure S7. Detection of cleaved CTNNB1 mRNA by 5'RACE-Seq; Figure S8. EnCore-mediated delivery to CTNNB1/YAP-driven hepatoblastoma; Figure S9: Tolerability profile of EnCore-R/CTNNB1 DsiRNA in nonhuman primates.

Neuroendocrine transdifferentiation (NED) of prostate cancer (PCa) is the main cause of failure of androgen receptor inhibitor treatment. However, the molecular mechanisms underlying the development of NEPC, especially treatment-induced NEPC, remain unclear. Emerging evidence indicates that elevated monoamine oxidase A (MAOA) contribute to the proliferation, cell stemness, and bone metastasis in PCa. Here, we generated an enzalutamide-induced NED cell model to assess the role of MAOA during NED. Overall, MAOA expression was significantly increased upon Enz long-term exposure and was required for neuroendocrine marker expression. In particular, Enz was found to induce NED via the MAOA/mTOR/HIF-1α signaling axis. Further analyses revealed that the MAOA inhibitor clorgyline(CLG) may bring multiple benefits to CRPC patients, including better therapeutic effect and delays NED. These findings suggest that MAOA may be an important target for the development of anti-NED therapies, thereby providing a novel strategy for the combined application of CLG and AR inhibitors in the clinic.

Although Janus membranes have been fabricated for the separation of oil/water mixtures, simplifying the construction processes is still a thorny challenge. In this work, a facile and easily scale-up approach based on in situ mussel-inspired chemistry is reported for the first time to prepare the Janus membrane with unidirectional oil/water separation. Here, the poly (vinylidene fluoride)/polydopamine/polyethylenimine (PVDF/PDA/PEI) membranes on the polyester non-woven fabric were fabricated via non-solvent induced phase separation (NIPS) technique. In the coagulation bath, the reactive oxygen species (ROS) produced by CuSO4/H2O2 improved the formation of the hydrophilic PDA/PEI on the top surface of the membrane. The hydrophobic bottom surface was received after the membrane was stripped from the supporting fabric. Scanning electronic microscopy (SEM), confocal laser scanning microscopy (CLSM), attenuated total reflectance Fourier transform infrared spectrometer (ATR-FTIR), X-ray photoelectron spectroscopy (XPS) and energy dispersive spectrometer (EDS) were used to characterize the membrane. The Janus membrane showed asymmetric wettability with 152.2° underwater oil contact angle of F-T5 and 153.3° underoil water contact angle of B-T5. Furthermore, by this in situ mussel-inspired chemistry, the Janus membrane showed excellent water and oil separation, antifouling performance and stability, which can potentially be used for unidirectional oil/water separation.

The Wnt/β-catenin pathway is among the most frequently altered signaling networks in human cancers. Despite decades of preclinical and clinical research, efficient therapeutic targeting of Wnt/β-catenin has been elusive. RNA interference (RNAi) technology silences genes at the mRNA level and therefore can be applied to previously undruggable targets. Lipid nanoparticles (LNP) represent an elegant solution for the delivery of RNAi-triggering oligonucleotides to disease-relevant tissues, but have been mostly restricted to applications in the liver. In this study, we systematically tuned the composition of a prototype LNP to enable tumor-selective delivery of a Dicer-substrate siRNA (DsiRNA) targeting CTNNB1, the gene encoding β-catenin. This formulation, termed EnCore-R, demonstrated pharmacodynamic activity in subcutaneous human tumor xenografts, orthotopic patient-derived xenograft (PDX) tumors, disseminated hematopoietic tumors, genetically induced primary liver tumors, metastatic colorectal tumors, and murine metastatic melanoma. DsiRNA delivery was homogeneous in tumor sections, selective over normal liver and independent of apolipoprotein-E binding. Significant tumor growth inhibition was achieved in Wnt-dependent colorectal and hepatocellular carcinoma models, but not in Wnt-independent tumors. Finally, no evidence of accelerated blood clearance or sustained liver transaminase elevation was observed after repeated dosing in nonhuman primates. These data support further investigation to gain mechanistic insight, optimize dose regimens, and identify efficacious combinations with standard-of-care therapeutics. Mol Cancer Ther; 15(9); 2143–54. ©2016 AACR.

Primary hyperoxaluria type 1 (PH1) is an autosomal recessive, metabolic disorder caused by mutations of alanine-glyoxylate aminotransferase (AGT), a key hepatic enzyme in the detoxification of glyoxylate arising from multiple normal metabolic pathways to glycine. Accumulation of glyoxylate, a precursor of oxalate, leads to the overproduction of oxalate in the liver, which accumulates to high levels in kidneys and urine. Crystalization of calcium oxalate (CaOx) in the kidney ultimately results in renal failure. Currently, the only treatment effective in reduction of oxalate production in patients who do not respond to high-dose vitamin B6 therapy is a combined liver/kidney transplant. We explored an alternative approach to prevent glyoxylate production using Dicer-substrate small interfering RNAs (DsiRNAs) targeting hydroxyacid oxidase 1 (HAO1) mRNA which encodes glycolate oxidase (GO), to reduce the hepatic conversion of glycolate to glyoxylate. This approach efficiently reduces GO mRNA and protein in the livers of mice and nonhuman primates. Reduction of hepatic GO leads to normalization of urine oxalate levels and reduces CaOx deposition in a preclinical mouse model of PH1. Our results support the use of DsiRNA to reduce liver GO levels as a potential therapeutic approach to treat PH1.

Wnt/β-catenin signaling mediates cancer immune evasion and resistance to immune checkpoint therapy, in part by blocking cytokines that trigger immune cell recruitment. Inhibition of β-catenin may be an effective strategy for increasing the low response rate to these effective medicines in numerous cancer populations. DCR-BCAT is a nanoparticle drug product containing a chemically optimized RNAi trigger targeting CTNNB1, the gene that encodes β-catenin. In syngeneic mouse tumor models, β-catenin inhibition with DCR-BCAT significantly increased T cell infiltration and potentiated the sensitivity of the tumors to checkpoint inhibition. The combination of DCR-BCAT and immunotherapy yielded significantly greater tumor growth inhibition (TGI) compared to monotherapy in B16F10 melanoma, 4T1 mammary carcinoma, Neuro2A neuroblastoma, and Renca renal adenocarcinoma. Response to the RNAi-containing combination therapy was not dependent on Wnt activation status of the tumor. Importantly, this drug combination was associated with elevated levels of biomarkers of T cell-mediated cytotoxicity. Finally, when CTLA-4 and PD-1 antibodies were combined with DCR-BCAT in MMTV-Wnt1 transgenic mice, a genetic model of spontaneous Wnt-driven tumors, complete regressions were achieved in the majority of treated subjects. These data support RNAi-mediated β-catenin inhibition as an effective strategy to increase response rates to cancer immunotherapy., Graphical Abstract, Immune checkpoint inhibitors including PD-(L)1 antibodies have shown great potential for treating diverse human cancers, but relatively few patients achieve durable responses. Using murine tumor models, Ganesh et al. demonstrate that co-treatment with an optimized β-catenin-targeting RNAi agent increases sensitivity to immunotherapy by promoting the infiltration of cytotoxic T cells.

Colorectal carcinomas harbor well-defined genetic abnormalities, including aberrant activation of Wnt/β-catenin and MAPK pathways, often simultaneously. Although the MAPK pathway can be targeted using potent small-molecule drugs, including BRAF and MEK inhibitors, β-catenin inhibition has been historically challenging. RNAi approaches have advanced to the stage of clinical viability and are especially well suited for transcriptional modulators, such as β-catenin. In this study, we report therapeutic effects of combined targeting of these pathways with pharmacologic agents. Using a recently described tumor-selective nanoparticle containing a β-catenin–targeting RNAi trigger, in combination with the FDA-approved MEK inhibitor (MEKi) trametinib, we demonstrate synergistic tumor growth inhibition in in vivo models of colorectal cancer, melanoma, and hepatocellular carcinoma. At dose levels that were insufficient to significantly impact tumor growth as monotherapies, combination regimens resulted in synergistic efficacy and complete tumor growth inhibition. Importantly, dual MEKi/RNAi therapy dramatically improved survival of mice bearing colorectal cancer liver metastases. In addition, pharmacologic silencing of β-catenin mRNA was effective against tumors that are inherently resistant or that acquire drug-induced resistance to trametinib. These results provide a strong rationale for clinical evaluation of this dual-targeting approach for cancers harboring Wnt/β-catenin and MAPK pathway mutations. Mol Cancer Ther; 17(2); 544–53. ©2017 AACR.

To replace full penetration weld with twin fillet weld for the design and construction of joint of beam to CFST (concrete-filled steel tube) column with interior strengthening ring, six specimens were tested by incremental loading and cyclic loading. The finite element package ANSYS was used to study the nonlinear behavior of such specimens. The finite element model was validated by comparing the computed values with experimental results. The failure mode was local buckling in the flange edge between beam flange and steel tube because of local stress concentration. When the joint was damaged, the stress of weld (including full penetration, partial penetration, and twin fillet weld) between steel tube and interior strengthening ring is smaller than yield strength. The twin fillet weld was proposed for design and construction of the joint instead of full penetration weld.

A replication-deficient recombinant adenovirus (Ad5-LFA-3/IgG(1)) that encodes secreted LFA-3/IgG(1) was constructed for gene therapy treatment of psoriasis. The purpose of this study was to develop a real-time PCR method for pharmacokinetic and biodistribution studies of Ad5-LFA-3/IgG(1) within the circulation and organs. This method showed good specificity, sensitivity and reproducibility over a wide dynamic range of concentrations. Quantitative measurement of recombinant adenoviral DNA suggested that the level of Ad5-LFA-3/IgG(1) DNA in circulating blood peaked within 10 min following intravenous injection in rhesus macaques. Following this peak, the adenoviral DNA level dropped significantly to a very low level. Real-time PCR revealed that Ad5-LFA-3/IgG(1) DNA was enriched in the spleen, lung and liver after injection of the adenovirus into rats through the tail vein. The adenoviral DNA was barely detected in other tissues. These data provide important information for clinical trials of Ad5-LFA-3/IgG(1) and confirm the utility of the real-time PCR assay for monitoring gene therapy trials.

OBJECTIVE Plant metabolomics combined with GC-MS was used to investigate metabolic fingerprinting of Tussilago farfara at different growth stages. METHOD Dried Samples were extracted by two-phase solvent system to obtain polar and nonpolar parts, which were subjected to GC-MS analysis. Metabolites were identified by NIST data base search and comparison with the authentic standards. The data were introduced into SIMCA-P 11.0 software package for multivariate analysis after pretreatment. RESULT Fifty-four metabolites were identified, including 35 polar metabolites and 19 nonpolar compounds. The score plot for PCA showed clear separation of the different development stages of flower buds of T. farfara, showing a trend of gradual change. Samples of October, November, December were in close proximity on the plot, indicating that the metabolome of these three periods was similar, samples from September (early development) and March (after flowering) were far away, showing big chemical differences. Content comparison results of some representative metabolites reveals that, the content of proline, lysine and linoleic acid increased gradually to the highest in the medium term, but sharply decreased to the lowest after flowering; the content of malic acid and citric acid were the lowest in the medium term; sucrose content decreased gradually, and then reached the lowest level after blooming. CONCLUSION It is obvious that metabolites of the early development and flowering stage were quite different with those of the traditional harvest time, suggesting that they can not be used as traditional medicine. This study will provide a research basis for harvest time determination and bioactive compounds of T. farfara.

Luminescent 50-nm silicon dioxide nanoparticles containing both types of rhodamine 6G (R; particles denoted R-SiO2) were synthesized by the sol–gel method. In the presence of Pb(Ac)2 as a heavy atom perturber the particle can emit the intense and stable room-temperature phosphorescence (RTP) signal of R on a polyamide membrane, with λ ex max /λ em max =470/635 nm for R. Our research indicates that the specific immune reaction between goat-anti-human IgG antibody labeled with R-SiO2 and human IgG can be carried out quantitatively on a polyamide membrane, and the phosphorescence intensity was enhanced after the immunoreaction. Thus a new method for solid-substrate room-temperature phosphorescence immunoassay (SS-RTP-IA) for determination of human IgG was established on the basis of antibody labeled with the nanoparticles containing binary luminescent molecules. The linear range of this method is 0.0624–20.0 pg spot−1 of human IgG (corresponding to a concentration range of 0.156–50.0 ng mL−1, sample volume 0.40 μL spot−1). The regression equations of the working curves are ΔIp=71.27+7.208mIgG (pg spot−1) (r=0.9996). Detection limits calculated as 3Sb/k are 0.022 pg spot−1. Compared with the same IA using fluorescein isothiocyanate (FITC) as the marker the new method was more sensitive and had a wider linear range. After elevenfold replicate measurement RSD are 4.5 and 3.6% for samples containing 0.156 and 50.0 ng mL−1 IgG, respectively. This method is sensitive, accurate, and of high precision.