[Show abstract][Hide abstract] ABSTRACT: YM155, a small molecule inhibitor of the antiapoptotic protein survivin, has been developed as a potential anti-cancer drug. We investigated a combination therapy of YM155 and interleukin-2 (IL-2) in a mouse model of renal cell carcinoma (RCC). YM155 caused cell cycle arrest and apoptosis in renal cancer (RENCA) cells. Next, luciferase-expressing RENCA cells were implanted in the left kidney and the lung of BALB/c mice to develop RCC metastatic model. In this orthotopic renal and metastatic lung tumors models, YM155 and IL-2 additively decreased tumor weight, lung metastasis, and luciferin-stained tumor images. Also, the combination significantly suppressed regulatory T cells and myeloid-derived suppressor cells compared with single agent treatment. We suggest that a combination of YM155 and IL-2 can be tested as a potential therapeutic modality in patients with RCC.
[Show abstract][Hide abstract] ABSTRACT: Mesothelin (MSLN) is a 40-kDa cell differentiation-associated glycoprotein appearing with carcinogenesis and is highly expressed in many human cancers, including the majority of pancreatic adenocarcinomas, ovarian cancers, and mesotheliomas, while its expression in normal tissue is limited to mesothelial cells lining the pleura, pericardium, and peritoneum. Clone 11-25 is a murine hybridoma secreting monoclonal antibody (mAb) against human MSLN. In this study, we applied the 11-25 mAb to in vivo imaging to detect MSLN-expressing tumors. In in vitro and ex vivo immunochemical studies, we demonstrated specificity of 11-25 mAb to membranous MSLN expressed on several pancreatic cancer cells. We showed the accumulation of Alexa Fluor 750-labeled 11-25 mAb in MSLN-expressing tumor xenografts in athymic nude mice. Then, 11-25 mAb was labeled with (64)Cu via a chelating agent DOTA and was used in both in vitro cell binding assay and in vivo positron emission tomography (PET) imaging in the tumor-bearing mice. We confirmed that (64)Cu-labeled 11-25 mAb highly accumulated in MSLN-expressing tumors as compared to MSLN-negative ones. The (64)Cu-labeled 11-25 mAb is potentially useful as a PET probe capable of being used for wide range of tumors, rather than (18)F-FDG that occasionally provides nonspecific accumulation into the inflammatory lesions.
Journal of Immunology Research 04/2015; 2015:268172. DOI:10.1155/2015/268172 · 2.93 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Reduced expression in immortalized cells (REIC)/Dickkopf (Dkk)-3 is a tumor-suppressor gene and has been studied as a promising therapeutic gene for cancer gene therapy. Intratumoral injection of an adenovirus vector carrying the human REIC/Dkk-3 gene (Ad-REIC) elicits cancer cell‑specific apoptosis and anticancer immune responses. The cytokine-like effect of secretory REIC/Dkk-3 on the induction of dendritic cell (DC)-like cell differentiation from monocytes plays a role in systemic anticancer immunity. In the present study, we generated recombinant full-length and N-terminally truncated REIC/Dkk-3 to characterize the biological activity of the protein. During the purification procedure, we identified a 17 kDa cysteine-rich stable product (C17-REIC) showing limited degradation. Further analysis showed that the C17-REIC domain was sufficient for the induction of DC-like cell differentiation from monocytes. Concomitant with the differentiation of DCs, the REIC/Dkk-3 protein induced the phosphorylation of glycogen synthase kinase 3β (GSK-3β) and signal transducers and activators of transcription (STAT) at a level comparable to that of granulocyte/macrophage colony‑stimulating factor. In a mouse model of subcutaneous renal adenocarcinoma, intraperitoneal injection of full-length and C17-REIC proteins exerted anticancer effects in parallel with the activation of immunocompetent cells such as DCs and cytotoxic T lymphocytes in peripheral blood. Taken together, our results indicate that the stable cysteine-rich core region of REIC/Dkk-3 is responsible for the induction of anticancer immune responses. Because REIC/Dkk-3 is a naturally circulating serum protein, the upregulation REIC/Dkk-3 protein expression could be a promising option for cancer therapy.
[Show abstract][Hide abstract] ABSTRACT: Immunotherapy is one of the attractive treatment strategies for advanced prostate cancer. The US Food and Drug Administration (FDA) previously approved the therapeutic vaccine, sipuleucel-T, which is composed of autologous antigen-presenting cells cultured with a fusion protein [prostatic acid phosphatase (PAP) and granulocyte-macrophage colony-stimulating factor (GMCSF)]. Although sipuleucel-T has been shown to prolong the median survival of patients for 4.1 months, more robust therapeutic effects may be expected by modifying the vaccination protocol. In the present study, we aimed to develop and validate a novel vaccination strategy using multiple PAP-fused cytokines for prostate cancer treatment. Using a super gene expression (SGE) system that we previously established to amplify the production of a recombinant protein, significant amounts of PAP-fused cytokines [human GMCSF, interleukin-2 (IL2), IL4, IL7 and mouse GMCSF and IL4] were obtained. We examined the activity of the fusion proteins in vitro to validate their cytokine functions. A significant upregulation of dendritic cell differentiation from monocytes was achieved by PAP-GMCSF when used with the other PAP-fused cytokines. The PAP-fused human IL2 significantly increased the proliferation of lymphocytes, as determined by flow cytometry. We also investigated the in vivo therapeutic effects of multiple PAP-fused cytokines in a mouse prostate cancer model bearing prostate-specific antigen (PSA)- and PAP-expressing tumors. The simultaneous intraperitoneal administration of PAP-GMCSF, -IL2, -IL4 and -IL7 significantly prevented tumor induction and inhibited the tumor growth in the PAP-expressing tumors, yet not in the PSA-expressing tumors. The in vivo therapeutic effects with the multiple PAP-fused cytokines were superior to the effects of PAP-GMCSF alone. We thus demonstrated the advantages of the combined use of multiple PAP-fused cytokines including PAP-GMCSF, and propose a promising prostatic antigen-vaccination strategy to enhance the therapeutic effects.
[Show abstract][Hide abstract] ABSTRACT: Reduced expression in immortalized cells/Dickkopf-3 (REIC/Dkk-3) was identified as a gene whose expression is reduced in many human cancers. REIC/Dkk-3 expression is also downregulated in malignant glioma and regulates cell growth through caspase-dependent apoptosis. cRGD (EMD121974), an antagonist of integrins, has demonstrated preclinical efficacy against malignant glioma. In this study, we investigated the antiglioma effect of combination therapy using an adenovirus vector carrying REIC/Dkk-3 (Ad-REIC) and cRGD. Quantitative real-time reverse-transcription PCR revealed the reduction of REIC/Dkk-3 mRNA levels in malignant glioma cell lines. The reduction of REIC/Dkk-3 protein expression in malignant glioma cell lines was also confirmed with western blot analysis. After treatment with Ad-REIC and cRGD, the proliferative rate of malignant glioma cells was significantly reduced in a time-dependent manner. In vivo, there was a statistically significant increase in the survival of mice treated with Ad-REIC and cRGD combination therapy compared with Ad-REIC monotherapy. We identified an apoptotic effect following monotherapy with Ad-REIC. Moreover, cRGD augmented the antiglioma efficacy of Ad-REIC. These results may lead to a promising new approach for the treatment of malignant glioma.Gene Therapy advance online publication, 13 November 2014; doi:10.1038/gt.2014.100.
[Show abstract][Hide abstract] ABSTRACT: Through genome-wide association analysis and an independent replication study using a total of 1131 bladder cancer cases and
12 558 non-cancer controls of Japanese populations, we identified a susceptibility locus on chromosome 15q24. SNP rs11543198
was associated with bladder cancer risk with odds ratio (OR) of 1.41 and P-value of 4.03 × 10−9. Subgroup analysis revealed rs11543198 to have a stronger effect in male smokers with OR of 1.66. SNP rs8041357, which is
in complete linkage disequilibrium (r2 = 1) with rs11543198, was also associated with bladder cancer risk in Europeans (P = 0.045 for an additive and P = 0.025 for a recessive model), despite much lower minor allele frequency in Europeans (3.7%) compared with the Japanese
(22.2%). Imputational analysis in this region suggested CYP1A2, which metabolizes tobacco-derived carcinogen, as a causative
candidate gene. We also confirmed the association of previously reported loci, namely SLC14A1, APOBEC3A, PSCA and MYC, with bladder cancer. Our finding implies the crucial roles of genetic variations on the chemically associated development
of bladder cancer.
Human Molecular Genetics 10/2014; 24(4). DOI:10.1093/hmg/ddu512 · 6.39 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The Wnt signaling pathway plays a crucial role in human cancer development, and axis inhibition protein 2 (Axin2) is a master scaffold protein involved in Wnt signaling. Axin2 negatively regulates Wnt signaling and acts as a tumor suppressor protein. The present study evaluated the association between the Axin2 single nucleotide polymorphism (SNP) rs2240308 [guanine (G)/adenine (A)] and the incidence of prostate cancer. In total, 103 patients with prostate cancer and 100 cancer-free control males were included in this case-control study, and were genotyped using the genomic DNA extracted from peripheral blood samples. The results revealed a higher incidence of prostate cancer in the subjects with the homozygous GG genotype and a reduced cancer incidence in the patients with the GA genotype of the rs2240308 SNP (G/A) in the Axin2 gene. The adjusted odds ratio for carriers with the GA genotype was 0.377 (95% CI, 0.206-0.688; P=0.001) and that for the AA genotype was 0.830 (95% CI, 0.309-2.232; P=0.712) compared with the GG genotype. Therefore, the GA genotype was found to exhibit a protective effect that decreased the risk of prostate cancer. To the best of our knowledge, this is the first study to demonstrate the significant association between this SNP (rs2240308, G/A) and the risk of prostate cancer. This association indicates the possibility that the variations in the Axin2 gene in this position may play a significant role in promoting the development of cancer in the prostate. We believe that the Axin2 SNP (rs2240308) could be a useful biomarker for the predisposition and early diagnosis of the disease.
[Show abstract][Hide abstract] ABSTRACT: Dickkopf (DKK) proteins interact with low-density lipoprotein receptor-related protein 5/6 (LRP5/6) to modulate WNT signaling. The interaction is mediated by a cysteine-rich domain (C2) in the DKK protein and beta-propeller domains (PD) of LRP5/6. However, the third member of the DKK family (DKK3) does not bind to LRP5/6. To determine why DKK3 does not bind to the receptor domains, we performed a molecular modeling simulation study including homology modeling, protein-protein docking and molecular dynamics (MD). The computed affinities (ΔGbinding) between the C2 and PD models were consistent with the previously reported experimental results. The C2 model of DKK3 showed the lowest affinity for PD models. Multiple sequence alignment of C2 domains revealed that the DKK3 genes have a unique 7-amino-acid insertion (L249-E255 in human DKK3) and P258 in a finger loop 1 (FL1). Interestingly, the insertion sequence is evolutionally conserved. MD simulations of high-affinity complex models of C2 and PD showed that FL1 directly interacts with the PD models and stabilizes the complex models. We also built a 7-amino-acid-deletion/P258G mutant model of DKK3C2 and estimated its affinities for the PD models. The affinity for human LRP5PD2 was increased by the substitution (ΔGbinding＝－48.9kcal/mol) and the affinity was compatible with that of high-affinity ligands. The results suggested that the lack of affinity between human DKK3 and human LRP5/6 results from: i) insertion of the 7 amino acids, and ii) P258 in human DKK3. The sequence differences thus suggest an explanation for this unique property of DKK3.
[Show abstract][Hide abstract] ABSTRACT: We conducted a study on molecular epidemiology and clinical implications of metallo-beta-lactamase (MBL)-producing Pseudomonas aeruginosa isolated from urine. Over a 10-year period from 2001 through 2010, a total of 92 MBL-producing P. aeruginosa urine isolates were collected from patients (one isolate per patient) who were admitted to 5 hospitals in Okayama Prefecture, Japan. When cross-infection was suspected in the hospital, pulsed-field gel electrophoresis was performed. In the resulting dendrogram of 79 MBL-producing P. aeruginosa urine isolates, no identical isolates and 7 pairs of isolates with >80% similarity were found. The biofilm-forming capabilities of 92 MBL-producing P. aeruginosa urine isolates were significantly greater than those of 92 non-MBL-producing urine isolates in a medium of modified artificial urine. The imipenem resistance transferred in 16 of 18 isolates tested, and these frequencies were in the range of 10－3 to 10－9. All of 18 isolates tested belonged to internationally spread sequence type 235 and had 3 gene cassettes of antimicrobial resistance genes in the class 1 integron. The strong biofilm-forming capabilities of MBL-producing P. aeruginosa urine isolates could be seriously implicated in nosocomial infections. To prevent spread of the organism and transferable genes, effective strategies to inhibit biofilm formation in medical settings are needed.
[Show abstract][Hide abstract] ABSTRACT: The National Institutes of Health Chronic Prostatitis Symptom Index (NIH-CPSI) is the standard questionnaire that determines the degree of symptoms and efficacy of treatment in patients with chronic prostatitis/chronic pelvic pain syndrome. Because there was no officially approved Japanese version of the NIH-CPSI, the Japanese Urological Association (JUA) formed a committee to develop one chaired by Dr. Masayuki Takeda, who also chairs the special field of voiding function and neurourology in the JUA. Consequently, the committee produced a Japanese version, referring to previous proposals and the Japanese version of the International Prostate Symptom Score. The committee strongly expects that the Japanese version of the NIH-CPSI will be taken full advantage of in future clinical research.
Nippon Hinyōkika Gakkai zasshi. The japanese journal of urology 04/2014; 105(2):62-5. DOI:10.5980/jpnjurol.105.62
[Show abstract][Hide abstract] ABSTRACT: Reduced expression in immortalized cells (REIC)/Dickkopf (Dkk)-3 is a tumor suppressor and therapeutic gene and has been studied with respect to the application of cancer gene therapy. Our previous studies demonstrated that the intratumoral injection of an adenovirus vector carrying the human REIC/Dkk-3 gene (Ad-REIC) suppresses tumor growth in mouse models of prostate, breast and testicular cancer and malignant mesothelioma. The mechanisms underlying these antitumor therapeutic effects have only been clarified recently. It has been demonstrated that Ad-REIC treatment inhibits cancer progression via the upregulation of systemic anticancer immunity. Under experimental conditions, autologous cancer vaccination via cancer-specific apoptosis and anticancer immune activation is a possible therapeutic mechanism. The robust anticancer effects observed in previous preclinical studies support the clinical utility of Ad-REIC. At present, a phase I-IIa study of Ad-REIC gene therapy in prostate cancer patients is ongoing. The current study reviews the observations of previous fundamental studies and summarizes the anticancer mechanisms of intratumoral Ad-REIC treatment in terms of cancer vaccination.
[Show abstract][Hide abstract] ABSTRACT: For expression of genes in mammalian cells, various vectors have been developed using promoters including CMV, EF-1α, and CAG promoters and have been widely used. However, such expression vectors sometimes fail to attain sufficient expression levels depending on the nature of cargo genes and/or on host cell types. In the present study, we aimed to develop a potent promoter system that enables high expression levels of cargo genes ubiquitously in many different cell types. We found that insertion of an additional promoter downstream of a cargo gene greatly enhanced the expression levels. Among the constructs we tested, C-TSC cassette (C: CMV-RU5' located upstream; TSC: another promoter unit composed of triple tandem promoters, hTERT, SV40, and CMV, located downstream of the cDNA plus a polyadenylation signal) had the most potent capability, showing far higher efficiency than that of potent conventional vector systems. The results indicate that the new expression system is useful for production of recombinant proteins in mammalian cells and for application as a gene therapeutic measure.
[Show abstract][Hide abstract] ABSTRACT: REIC/Dkk-3 is down-regulated in a broad range of human cancer cells and is considered to function as a tumor suppressor. We previously reported that REIC/Dkk-3-expressing adenovirus vector (Ad-REIC) induced endoplasmic reticulum (ER) stress and cancer-specific apoptosis in human prostate cancer. In this study, we examined the therapeutic impact of Ad-REIC on non-small cell lung cancer (NSCLC).
We examined the anti-tumor effect of Ad-REIC on 25 NSCLC cell lines in vitro and A549 cells in vivo. Two of these cell lines were artificially established as EGFR-tyrosine kinase inhibitor (TKI) resistant sublines.
Ad-REIC-treatment inhibited the cell viability by 40% or more in 13 (52%) of the 25 cell lines at multiplicity of infection (MOI) of 20 (20 MOI). These cell lines were regarded as being highly sensitive cells. The cell viability of a non-malignant immortalized cell line, OUMS-24, was not inhibited at 200 MOI of Ad-REIC. The effects of Ad-REIC on EGFR-TKI resistant sublines were equivalent to those in the parental cell lines. Here, we demonstrated that Ad-REIC treatment activated c-Jun N-terminal kinase (JNK) in NSCLC cell lines, indicating the induction of ER stress with GRP78/BiP (GRP78) up-regulation and resulting in apoptosis. A single intratumoral injection of Ad-REIC significantly inhibited the tumorigenic growth of A549 cells in vivo. As predictive factors of sensitivity for Ad-REIC treatment in NSCLC, we examined the expression status of GRP78 and coxsackievirus and adenovirus receptor (CAR). We found that the combination of the GRP78 and CAR expressional statuses may be used as a predictive factor for Ad-REIC sensitivity in NSCLC cells.
Ad-REIC induced JNK activation and subsequent apoptosis in NSCLC cells. Our study indicated that Ad-REIC has therapeutic potential against NSCLC and that the expression statuses of GRP78 and CAR may predict a potential therapeutic benefit of Ad-REIC.
PLoS ONE 02/2014; 9(2):e87900. DOI:10.1371/journal.pone.0087900 · 3.23 Impact Factor