New Pyridone-Based Derivatives as Cannabinoid Receptor Type 2 Agonists.

The activation of the human cannabinoid receptor type II (CB2R) is known to mediate analgesic and anti-inflammatory processes without the central adverse effects related to cannabinoid receptor type I (CB1R). In this work we describe the synthesis and evaluation of a novel series of N-aryl-2-pyridone-3-carboxamide derivatives tested as human cannabinoid receptor type II (CB2R) agonists. Different cycloalkanes linked to the N-aryl pyridone by an amide group displayed CB2R agonist activity as determined by intracellular [cAMP] levels. The most promising compound 8d exhibited a non-toxic profile and similar potency (EC50 = 112 nM) to endogenous agonists Anandamide (AEA) and 2-Arachidonoylglycerol (2-AG) providing new information for the development of small molecules activating CB2R. Molecular docking studies showed a binding pose consistent with two structurally different agonists WIN-55212-2 and AM12033 and suggested structural requirements on the pyridone substituents that can satisfy the orthosteric pocket and induce an agonist response. Our results provide additional evidence to support the 2-pyridone ring as a suitable scaffold for the design of CB2R agonists and represent a starting point for further optimization and development of novel compounds for the treatment of pain and inflammation.

Novel N-Arylsulfonylindoles Targeted as Ligands of the 5-HT6 Receptor. Insights on the Influence of C-5 Substitution on Ligand Affinity.

A new series of twenty-two C-5 substituted N-arylsulfonylindoles was prepared with the aim of exploring the influence of C-5 substitution on 5-HT6 receptor affinity. Eleven compounds showed moderate to high affinity at the receptor (Ki = 58-403 nM), with compound 4d being identified as the most potent ligand. However, regarding C-5 substitution, both methoxy and fluorine were detrimental for receptor affinity compared to our previously published unsubstituted compounds. In order to shed light on these observations, we performed docking and molecular dynamics simulations with the most potent compounds of each series (4d and 4l) and PUC-10, a highly active ligand previously reported by our group. The comparison brings about deeper insight about the influence of the C-5 substitution on the binding mode of the ligands, suggesting that these replacements are detrimental to the affinity due to precluding a ligand from reaching deeper inside the binding site. Additionally, CoMFA/CoMSIA studies were performed to systematize the information of the main structural and physicochemical characteristics of the ligands, which are responsible for their biological activity. The CoMFA and CoMSIA models presented high values of q2 (0.653; 0.692) and r2 (0.879; 0.970), respectively. Although the biological activity of the ligands can be explained in terms of the steric and electronic properties, it depends mainly on the electronic nature.

Intravitreal Injection of AAV Expressing Soluble VEGF Receptor-1 Variant Induces Anti-VEGF Activity and Suppresses Choroidal Neovascularization.

Purpose: With anti-VEGF-based treatments for wet AMD requiring frequent injections, it is often burdensome to both patients and healthcare providers. To explore its possibility as a desirable alternative, we investigated the therapeutic potential of a recombinant adeno-associated virus 2 expressing a soluble variant of VEGF receptor-1 (rAAV2-sVEGFRv-1) in a laser-induced choroidal neovascularization (CNV) model, as CNV is a defining feature of AMD progression. Methods: C57/B6 mice were intravitreally administered with rAAV2-sVEGFRv-1, rAAV2-GFP, or clinically used bevacizumab after CNV lesions were induced via laser photocoagulation. Immunostaining was performed with phalloidin and CD31 to measure CNV extensiveness, F4/80 and CD11b for inflammatory cell infiltration, and pan-cytokeratin to visualize fibrotic progression. Results: rAAV2-sVEGFRv-1 (5.0 × 107 viral genomes) possesses antiangiogenic, anti-inflammatory, and antifibrotic properties. rAAV2-sVEGFRv-1 was demonstrated to significantly decrease retinal CNV lesion size (1336 ± 186) when compared to rAAV2-GFP-treated (2949 ± 437, P = 0.0043), mock-treated (3075 ± 265, P = 0.0013), and bevacizumab-treated models (995 ± 234). Infiltration by inflammatory cells significantly decreased with rAAV2-sVEGFRv-1 administration, while groups treated with rAAV2-GFP did not. Additionally, antiapoptotic activity was observed via TUNEL assay in rAAV2-sVEGFRv-1 (16.0 ± 3.6) and rAAV2-GFP (46.0 ± 7.5, P = 0.003). Overall, the rAAV2-sVEGFRv-1 viral vector was positively comparable to bevacizumab, indicating it as effective as approved therapeutics. Conclusions: The ability of a low dose of rAAV2-sVEGFRv-1 to exert a therapeutically relevant anti-VEGF effect in a CNV model is demonstrated, and strongly suggests gene therapy as an effective and convenient treatment for sustained VEGF suppression.

Erratum to: Raloxifene Administration in Women Treated with Long Term Gonadotropin-releasing Hormone Agonist for Severe Endometriosis: Effects on Bone Mineral Density.

[This corrects the article on p. 174 in vol. 22, PMID: 28119898.].

Raloxifene Administration in Women Treated with Long Term Gonadotropin-releasing Hormone Agonist for Severe Endometriosis: Effects on Bone Mineral Density.

OBJECTIVES: To evaluate the efficacy of raloxifene in preventing bone loss associated with long term gonadotropin-releasing hormone agonist (GnRH-a) administration. METHODS: Twenty-two premenopausal women with severe endometriosis were treated with leuprolide acetate depot at a dosage of 3.75 mg/4 weeks, for 48 weeks. Bone mineral density (BMD) was evaluated at admission, and after 12 treatment cycles. RESULTS: At cycle 12 of GnRH-a plus raloxifene treatment, lumbar spine, trochanter femoral neck, and Ward's BMD differed from before the treatment. A year after treatment, the lumbar spine and trochanter decreased slightly, but were not significantly different. CONCLUSIONS: Our study shows that the administration of GnRH-a plus raloxifene in pre-menopausal women with severe endometriosis, is an effective long-term treatment to prevent bone loss.

Clinicopathologic factors influencing the accuracy of EUS for superficial esophageal carcinoma.

AIM: To identify clinicopathologic factors influencing the accuracy of a high-frequency catheter probe endoscopic ultrasonography (EUS) for superficial esophageal carcinomas (SECs). METHODS: A total of 126 patients with endoscopically suspected SEC, who underwent EUS and curative treatment at Pusan National University Hospital during 2005-2013, were enrolled. We reviewed the medical records of the 126 patients and compared EUS findings with histopathologic results according to clinicopathologic factors. RESULTS: A total of 114 lesions in 113 patients were included in the final analysis. The EUS assessment of tumor invasion depth was accurate in 78.9% (90/114) patients. Accuracy did not differ according to histologic type, tumor differentiation, tumor location, or macroscopic shape. However, accuracy significantly decreased for tumors ≥ 3 cm in size (P = 0.002). Overestimation and underestimation of the invasion depth occurred for 11 (9.6%) and 13 lesions (11.4%), respectively. In multivariate analyses, tumor size ≥ 3 cm was the only factor significantly associated with EUS accuracy (P = 0.031), and was specifically associated with the underestimation of invasion depth. CONCLUSION: EUS using a high-frequency catheter probe generally provides highly accurate assessments of SEC invasion depth, but its accuracy decreases for tumors ≥ 3 cm.

Identification of pro-inflammatory cytokines associated with muscle invasive bladder cancer; the roles of IL-5, IL-20, and IL-28A.

We used gene expression profiling to identify inflammatory cytokines that correlate with bladder cancer development. Gene expression profiles of the tissue samples were investigated using cDNA microarrays that contained 103 non-muscle invasive bladder cancers (NMIBC), 62 muscle invasive bladder cancers (MIBC), 58 samples of histologically normal-looking surrounding tissues, and 10 normal, healthy subjects who served as the control cohort for comparison. We grouped the data-sets according to biological characterizations and focused on immune response genes with at least 2-fold differential expression in MIBC vs. controls. The experimental data-set identified 36 immune-related genes that were significantly altered in MIBC samples. In addition, 10 genes were up-regulated and 26 genes were down-regulated in MIBC samples compared with the normal tissues. Among the 10 up-regulated molecules examined, the capacity for both wound-healing migration and invasion was enhanced in response to IL-5, IL-20, and IL-28A in bladder cancer cell lines (253J and EJ cells), compared with untreated cells. The expression levels of IL-5, IL-20, and IL-28A were increased in patients with MIBC. All 3 cytokines and their receptors were produced in bladder cancer cell lines, as determined by real-time PCR, immunoblot analysis and confocal immunofluorescence. Up-regulation of MMP-2 and MMP-9 was found after IL-5, IL-20, and IL-28A stimulation in both cell types. Moreover, an EMSA assay showed that treatment with IL-5, IL-20, and IL-28A induced activation of the transcription factors NF-κB and AP-1 that regulate the MMP-9 promoter. Finally, activation of MAPK and Jak-Stat signaling was observed after the addition of IL-5, IL-20, and IL-28A to bladder cancer cells. This study suggests the presence of specific inflammatory cytokine (IL-5, IL-20, and IL-28A)-mediated association in bladder cancer development. All 3 cytokines may be important new molecular targets for the modulation of migration and invasion in bladder cancer.

Inhibitory effects of the ethanol extract of Gleditsia sinensis thorns on human colon cancer HCT116 cells in vitro and in vivo.

The thorns of Gleditsia sinensis have traditionally been used in the treatment of several diseases, which includes their use as anti-tumor agents, but there has been no scientific evidence of this anti-tumor effect. However, the present study has identified a novel mechanism for the anti-tumor effect of Gleditsia sinensis thorns in the treatment of colon cancer. Treatment with the ethanol extract of Gleditsia sinensis thorns (EEGS) resulted in significant growth inhibition together with G2/M-phase cell cycle arrest at a dose of 600 microg/ml (IC50) in HCT116 cells. In addition, treatment with EEGS induced p27 expression and down-regulated expression of cyclins and cyclin-dependent kinases. Moreover, EEGS treatment induced phosphorylation of extracellular signal-regulated kinases (ERK), p38 MAP kinase and JNK (c-Jun N-terminal kinases). Among the pathways examined, only PD98059 (ERK-specific inhibitor) abolished EEGS-dependent p27 expression. Similarly, suppression of ERK function reversed EEGS-mediated cell proliferation inhibition and decreased cell cycle proteins. In addition, tumor necrosis factor-alpha (TNF-alpha)-induced matrix metalloproteinase-9 (MMP-9) expression was inhibited by EEGS treatment via decreased transcriptional activity of both activator protein-1 (AP-1) and nuclear factor-kappaB. Finally, EEGS treatment significantly reduced tumor sizes in HCT116 cell-xenografted tumor tissues, which was associated with the changed levels of ERK phosphorylation, p27 and MMP-9 expression. Overall, these results have identified a novel molecular mechanism for EEGS in the treatment of colon cancer and might provide a theoretical basis for the potential therapeutic use of EEGS in the treatment of malignancies.

Inhibitory effects of the aqueous extract of Magnolia officinalis on the responses of human urinary bladder cancer 5637 cells in vitro and mouse urinary bladder tumors induced by N-Butyl-N-(4-hydroxybutyl) nitrosamine in vivo.

This study investigated the anticancer activity of Magnolia officinalis on urinary bladder cancer in vitro and in vivo, and elucidated the mechanism of its activity. An aqueous extract of M. officinalis inhibited cell viability and DNA synthesis in cultured human urinary bladder cancer 5637 cells. Inhibition of proliferation was the result of apoptotic induction, because FACS analyses of 5637 cells treated with M. officinalis showed a sub-G1 phase accumulation. M. officinalis extract also increased cytoplasmic DNA-histone complex dose-dependently. These inhibitory effects were associated with the upregulation of proapoptotic molecules Bax, cytochrome c and caspase 3. Treatment of 5637 cells with M. officinalis extract suppressed the expression of matrix metalloproteinase 2 (MMP-2) and MMP-9, as revealed by zymographic and immunoblot analyses. When M. officinalis extract was given to mice simultaneously with the carcinogen N-butyl-N-(4-hydroxybutyl) nitrosamine, which induces urinary bladder tumors, the size of the induced tumors was smaller. Finally, histological data indicated that the histological grade of carcinoma and the depth of invasion were dramatically decreased by treatment with M. officinalis extract in mice with N-butyl-N-(4-hydroxybutyl) nitrosamine-induced urinary bladder tumors. In conclusion, the findings showed that M. officinalis extract exhibited potential chemopreventive activity against urinary bladder tumor in vitro and in vivo.

Transcriptional targeting of gene expression in breast cancer by the promoters of protein regulator of cytokinesis 1 and ribonuclease reductase 2.

For cancer gene therapy, cancer-specific over- expression of a therapeutic gene is required to reduce side effects derived from expression of the gene in normal cells. To develop such an expression vector, we searched for genes over-expressed and/or specifically expressed in cancer cells using bioinformatics and have selected genes coding for protein regulator of cytokinesis 1 (PRC1) and ribonuclease reductase 2 (RRM2) as candidates. Their cancer-specific expressions were confirmed in both breast cancer cell lines and patient tissues. We compared each promoter's cancer-specific activity in the breast normal and cancer cell lines using the luciferase gene as a reporter and confirmed cancer-specific expression of both PRC1 and RRM2 promoters. To test activities of these promoters in viral vectors, the promoters were also cloned into an adeno-associated viral (AAV) vector containing green fluorescence protein (GFP) as the reporter. The GFP expression levels by these promoters were various depending on cell lines tested and, in MDA-MB-231 cells, GFP activities derived from the PRC1 and RRM2 promoters were as strong as that from the cytomegalovirus (CMV) promoter. Our result showed that a vector containing the PRC1 or RRM2 promoter could be used for breast cancer specific overexpression in gene therapy.

Magnolol elicits activation of the extracellular signal-regulated kinase pathway by inducing p27KIP1-mediated G2/M-phase cell cycle arrest in human urinary bladder cancer 5637 cells.

Magnolol has been reported to play a role in antitumor activity. However, the relevant pathway integrating cell cycle regulation and signaling pathways involved in growth inhibition in cancer cells remains to be identified. In the present study, magnolol treatment of these cells resulted in significant dose-dependent growth inhibition together with apoptosis, G1- and G2/M-phase cell cycle arrest at a 60 microM (IC50) dose in 5637 bladder cancer cells. In addition, magnolol treatment strongly induced p27KIP1 expression, and down-regulated expression of cyclin-dependent kinases (CDKs) and cyclins. Moreover, treatment with magnolol-induced phosphorylation of ERK, p38 MAP kinase, and JNK. Among the pathway inhibitors examined, only PD98059, an ERK-specific inhibitor, blocked magnolol-dependent p27KIP1 expression. Blockade of ERK function consistently reversed magnolol-mediated inhibition of cell proliferation and decreased G2/M cell cycle proteins, but not G1 cell cycle proteins. Furthermore, magnolol treatment increased both Ras and Raf activation. Transfection of cells with dominant negative Ras (RasN17) and Raf (RafS621A) mutant genes suppressed magnolol-induced ERK activity and p27KIP1 expression. Finally, the magnolol-induced reduction in cell proliferation and G2/M cell cycle proteins was also abolished in the presence of RasN17 and RafS621A mutant genes. These data demonstrate that the Ras/Raf/ERK pathway participates in p27KIP1 induction, leading to a decrease in the levels of cyclin B1/Cdc2 complexes and magnolol-dependent inhibition of cell growth. Overall, these novel findings concerning the molecular mechanisms of magnolol in 5637 bladder cancer cells provide a theoretical basis for therapeutic treatment of malignancies.

Activation of matrix metalloproteinase-9 by TNF-alpha in human urinary bladder cancer HT1376 cells: the role of MAP kinase signaling pathways.

The expression of matrix metalloproteinase-9 (MMP-9) has been implicated in tumor invasion and metastasis. In this study, the factors and signaling pathways that are involved in the regulation of the MMP-9 expression were examined in urinary bladder cancer HT1376 cells. Tumor necrosis factor-alpha (TNF-alpha) stimulated the secretion of MMP-9 in HT1376 cells, as shown by zymography and immunoblot analysis. At the level of transcription, TNF-alpha also stimulated 5'-flanking promoter activity of MMP-9. Transcription factor NF-kappaB, AP-1 and Sp-1 binding sites were identified by a gel shift assay to be cis-elements for TNF-alpha activation of the MMP-9 promoter. TNF-alpha activates multiple signaling pathways in HT1376 cells, including the extracellular signal-regulated kinase (ERK1/2), p38 MAP kinase and JNK pathways. Chemical inhibitors, which specifically inhibit each of these TNF-alpha-activated pathways, were used to examine the signaling pathways involved in TNF-alpha-mediated MMP-9 expression. The ERK1/2 inhibitor, U0126 and the p38 MAP kinase inhibitor, SB203580, significantly down-regulated TNF-alpha-induced MMP-9 expression and promoter activity. The transactivation of TNF-alpha-stimulated NF-kappaB, AP-1 and Sp-1 were inhibited by U0126 and SB203580 treatment. In conclusion, the findings of the present study indicate that TNF-alpha induces MMP-9 expression in HT1376 cells by activating transcription factors, which are involved in the ERK1/2- and p38 MAP kinase-mediated control of MMP-9 regulation, namely, NF-kappaB, AP-1 and Sp-1.

Cancer gene therapy using adeno-associated virus vectors.

Gene therapy has offered highly possible promises for treatment of cancers, as many potential therapeutic genes involved in regulation of molecular processes may be introduced by gene transfer, which can arrest angiogenesis, tumor growth, invasion, metastasis, and/or can stimulate the immune response against tumors. Therefore, viral and non-viral gene delivery systems have been developed to establish an ideal delivery vector for cancer gene therapy over the past several years. Among the currently developed virus vectors, the adeno-associated virus (AAV) vector is considered as one of those that are closest to the ideal vector mainly for genetic diseases due to the following prominent features; the lack of pathogenicity and toxicity, ability to infect dividing and non-dividing cells of various tissue origins, a very low host immune response and long-term expression. Particularly, the most important attribute of AAV vectors is their safety profile in clinical trials ranging from CF to Parkinson's disease. Although adenovirus and several other oncolytic viruses have been more frequently used to develop cancer gene therapy, AAV also has many critical properties to be exploited for a cancer gene delivery vector. In this review, we will briefly summarize the basic biology of AAV and then mainly focus on recent progresses on AAV vector development and AAV-mediated therapeutic vectors for cancer gene therapy.

Aqueous extract of Magnolia officinalis mediates proliferative capacity, p21WAF1 expression and TNF-alpha-induced NF-kappaB activity in human urinary bladder cancer 5637 cells; involvement of p38 MAP kinase.

Magnolia officinalis is a commonly used herb in East Asian countries and has multiple pharmacological effects. Although Magnolia officinalis has a variety of pharmacological effects on certain cancer cell types, the molecular mechanisms on urinary bladder cancer are unclear. An aqueous extract of M. officinalis inhibited cell proliferation in cultured human urinary bladder cancer 5637 cells. Inhibition of proliferation was associated with G1 cell cycle arrest. Treatment with M. officinalis extract blocked the cell cycle in the G1 phase, down-regulated the expression of cyclins and CDKs and up-regulated the expressions of p21WAF1 and p27 Kip1, which are CDK inhibitors. In addition, M. officinalis extract induced a marked activation of p38 MAP kinase and JNK. SB203580, a p38 MAP kinase specific inhibitor, blocked the expression of M. officinalis extract-dependent p38 MAP kinase and p21WAF1. Blockage of the p38 MAPK kinase function reversed M. officinalis extract-induced cell proliferation. These data demonstrate that M. officinalis extract-induced cell growth inhibition appears to be linked to the activation of p38 MAP kinase through p21WAF1 expression. Moreover, treatment of 5637 cells with M. officinalis extract suppressed constitutive and TNF-alpha-induced-nuclear factor-kappa B (NF-kappaB) activation. Furthermore, the transactivation of TNF-alpha-stimulated NF-kappaB was inhibited by SB203580 treatment. Collectively, these results suggest that the p38 MAP kinase pathway contributes, at least partially, to the anti-cancer activity of M. officinalis extract in human urinary bladder tumor 5637 cells.

A novel way of therapeutic angiogenesis using an adeno-associated virus-mediated angiogenin gene transfer.

To develop a novel therapeutic angiogenesis for the treatment of cardiovascular diseases, angiogenin (ANG1) was examined as a potential therapeutic gene. An adeno-associated virus (AAV)-mediated gene delivery system was used to measure the therapeutic efficacy of ANG1. Using a triple co-transfection technique, rAAV-ANG1-GFP, rAAV- VEGF-GFP and rAAV-GFP vectors were produced, which were then used to infect human umbilical vein endothelial cells (HUVECs) in order to evaluate in vitro angiogenic activities. Their protein expressions, tagged with green fluorescent protein (GFP), were monitored by confocal microscopy. The functional activities were measured using wound- healing HUVEC migration assays. The number of migrated cells stimulated by both the expressed ANG1 and the VEGF in rAAV-infected HUVECs increased almost twice the number observed in the expressed GFP control. In vivo angiogenic activities of the expressed ANG1 or VEGF were determined using mouse angiogenesis assays. The angiogenic activities of ANG1 or VEGF expressed in the injected mice were increased by 1.36 and 2.16 times, respectively, compared to those of the expressed GFP control. These results demonstrate that the expressed ANG1 derived from rAAV infection has in vitro and in vivo angiogenic activities and suggest that the rAAV-ANG1 vector is a potential strategy for therapeutic angiogenesis.