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In the current study, we investigated a combination of docetaxel and thalidomide (DT therapy) in castration-resistant prostate cancer (CRPC) patients. We identified marker genes that predict the effect of DT therapy. Using an androgen-insensitive PC3 cell line, we established a docetaxel-resistant PC-3 cell line (DR-PC3). In DR-PC3 cells, DT therapy stronger inhibited proliferation/viability than docetaxel alone. Based on gene ontology analysis, we found versican as a selective gene. This result with the findings of cDNA microarray and validated by quantitative RT-PCR. In addition, the effect of DT therapy on cell viability was the same as the effect of docetaxel plus versican siRNA. In other words, silencing of versican can substitute for thalidomide. In the clinical setting, versican expression in prostate biopsy samples (before DT therapy) correlated with PSA reduction after DT therapy (p

// Hiroki Tamaki 1, 2 , Nanae Harashima 1 , Miho Hiraki 3 , Naoko Arichi 3 , Nobuhiro Nishimura 2 , Hiroaki Shiina 3 , Kohji Naora 2 , Mamoru Harada 1 1 Department of Immunology, Shimane University Faculty of Medicine, Shimane, Japan. 2 Department of Pharmacy, Shimane University Hospital, Shimane, Japan. 3 Department of Urology, Shimane University Faculty of Medicine, Shimane, Japan. Correspondence to: Mamoru Harada, e-mail: haramamo@med.shimane-u.ac.jp Keywords: prostate cancer, docetaxel, apoptosis, Bcl-2, Bcl-xL Received: July 26, 2014 Accepted: September 30, 2014 Published: October 15, 2014 ABSTRACT Docetaxel (DTX) is a useful chemotherapeutic drug for the treatment of hormone-refractory prostate cancer. However, emergence of DTX resistance has been a therapeutic hurdle. In this study, we investigated the effect of combining DTX with Bcl-2 family inhibitors using human prostate cancer cell lines (PC3, LNCaP, and DU145 cells). PC3 cells were less sensitive to DTX than were the other two cell lines. In contrast to ABT-199, which inhibits Bcl-2 and Bcl-w, both ABT-263 and ABT-737, which inhibit Bcl-2, Bcl-xL, and Bcl-w, significantly augmented the antitumor effect of DTX on PC3 cells. ABT-263 also enhanced the antitumor effect of DTX on a DTX-resistant PC3 variant cell line. The antitumor effect of ABT-263 was due mainly to its inhibitory effect on Bcl-xL. In a xenograft mouse model, DTX and ABT-737 combination therapy significantly inhibited PC3 tumor growth. Interestingly, although ABT-263 activated caspase-9 in PC3 cells, inhibition of caspase-9 unexpectedly promoted ABT-263-induced apoptosis in a caspase-8-dependent manner. This augmented apoptosis was also observed in LNCaP cells. These findings indicate that Bcl-xL inhibition can sensitize DTX-resistant prostate cancer cells to DTX, and they reveal a unique apoptotic pathway in which antagonism of Bcl-2 family members in caspase-9-inhibited prostate cancer cells triggers caspase-8-dependent apoptosis.

// Yozo Mitsui 1 , Hiroaki Yasumoto 1 , Taichi Nagami 1 , Miho Hiraki 1 , Naoko Arichi 1 , Noriyoshi Ishikawa 2 , Asuka Araki 2 , Riruke Maruyama 2 , Yuichiro Tanaka 3 , Rajvir Dahiya 3 , Hiroaki Shiina 1 1 Departments of Urology, Shimane University Faculty of Medicine, 89-1 Enya-cho, 693-8501 Izumo, Japan 2 Pathology (Organ Pathology Unit), Shimane University Faculty of Medicine, 89-1 Enya-cho, 693-8501 Izumo, Japan 3 Department of Urology, San Francisco Veterans Affairs Medical Center and University of California at San Francisco, San Francisco, California, USA Correspondence: Yozo Mitsui, email: // Keywords : adrenocortical tumor, Wif-1, epigenetics, Wnt signaling, cyclin D1 Received : March 24, 2014 Accepted : April 07, 2014 Published : April 08, 2014 Abstract Wnt/β-catenin signaling is considered to be an essential regulator of adrenocortical oncogenesis. Wnt inhibitory factor-1 (Wif-1), an extracellular regulator of Wnt signaling, is frequently down-regulated by hypermethylation of the promoter CpG. We investigated epigenetic regulation of Wif-1 and its association with adrenocortical (AC) tumor pathogenesis in light of Wnt activation. The AC tumors showed a high prevalence of Wif-1 promoter methylation and low prevalence of Wif-1 mRNA transcription as compared to the normal adrenal (NA) samples. Furthermore, a significant correlation was found between Wif-1 promoter methylation and mRNA transcription in the tumors. Either intracellular β-catenin accumulation or β-catenin mRNA transcription was significantly elevated in the AC tumors, which also showed an inverse correlation with Wif-1 mRNA transcription. Cyclin D1, a target gene of Wnt signaling, was also up-regulated in the AC tumors as compared with the NA samples. In addition, down-regulation of Wif-1was correlated with increased cyclin D1 at both mRNA and protein levels. However, despite the proposed activation of Wnt signaling in AC tumors, only 2 of 20 with intracellular β-catenin accumulation showed β-catenin mutations. Thus, genetic alterations of β-catenin and epigenetics-related Wif-1 promoter hypermethylation may be important mechanisms underlying AC tumor formation through aberrant canonical Wnt/β-catenin signaling activation.

Bladder cancer is the second most common genitourinary malignancy and has variable metastatic potential; however, choroidal and cutaneous metastases are extremely rare. Generally, a patient with these uncommon metastases has a very poor prognosis. We present a bladder cancer patient with a visual disorder in the right eye and multiple nodules on head and lower abdomen that developed 17 months after a radical cystectomy. These symptoms were determined to be caused by choroidal and cutaneous metastasis of bladder cancer. Although two cycles of combination chemotherapy were performed, the patient died 5 months after diagnosis of multiple metastases.

The proteoglycan versican (VCAN) promotes tumor progression and enhances metastasis in several cancers; however, its role in clear cell renal cell carcinoma (ccRCC) remains unknown. Recent evidence suggests that VCAN is an important target of chromosomal 5q gain, one of the most prevalent genetic abnormalities in ccRCC. Thus, we investigated whether VCAN expression is associated with the pathogenesis of ccRCC. VCAN expression was analyzed using three RCC and normal kidney cell lines as well as a clinical cohort of 84 matched ccRCC and normal renal tissues. Functional analyses on growth and progression properties were performed using VCAN-depleted ccRCC cells. Microarray expression profiling was employed to investigate the target genes and biologic pathways involved in VCAN-mediated ccRCC carcinogenesis. ccRCC had elevated VCAN expression in comparison with normal kidney in both cell lines and clinical specimens. The elevated expression of VCAN was significantly correlated with metastasis (P < 0.001) and worse 5-year overall survival after radical nephrectomy (P = 0.014). In vitro, VCAN knockdown significantly decreased cell proliferation and increased apoptosis in Caki-2 and 786-O cells, and this was associated with alteration of several TNF signaling–related genes such as TNFα, BID, and BAK. Furthermore, VCAN depletion markedly decreased cell migration and invasion which correlated with reduction of MMP7 and CXCR4. These results demonstrate that VCAN promotes ccRCC tumorigenesis and metastasis and thus is an attractive target for novel diagnostic, prognostic, and therapeutic strategies. Implications: This study highlights the oncogenic role of VCAN in renal cell carcinogenesis and suggests that this gene has therapeutic and/or biomarker potential for renal cell cancer. Mol Cancer Res; 15(7); 884–95. ©2017 AACR.

INTRODUCTION AND OBJECTIVES: Several epidemiologic reports using large cohorts suggest that tobacco smoking may be associated with prostate cancer (PC). Cytochrome P450 1A1 (CYP1A1) may play an important role in the initiation of various cancers including PC. However, the mechanisms of overexpression of CYP1A1 and smoking in PC have never been investigated. We assessed whether impaired regulation of CYP1A1 through DNA hypomethylation could be involved in smoking and contribute to the pathogenesis of PC. METHODS: We studied 3 PC cell lines, 69 benign hyperplasia (BPH) and 176 PC samples, using methylation-specific PCR analysis to focus on 3 regions of the CYP1A1 enhancer carrying a xenobiotic responsive element (XRE). In addition, we depleted the gene in LNCaP and DU145 by siRNA to validate its biological role in tumorigenesis. RESULTS: In all PC cell lines, CYP1A1 expression was enhanced after 5-aza-2-deoxycitidine treatment and bisulfite DNA sequencing confirmed hypermethylation at the CYP1A1 enhancer, indicating DNA promoter CpG methylation as a regulator of CYP1A1 expression. The level of methylation of CYP1A1 enhancer was significantly lower in PC as compared to BPH samples at all three enhancer sites (P

// Yozo Mitsui 1,2 , Hiroshi Hirata 2 , Naoko Arichi 1 , Miho Hiraki 1 , Hiroaki Yasumoto 1 , Inik Chang 3 , Shinichiro Fukuhara 4 , Soichiro Yamamura 2 , Varahram Shahryari 2 , Guoren Deng 2 , Sharanjot Saini 2 , Shahana Majid 2 , Rajvir Dahiya 2 , Yuichiro Tanaka 2 and Hiroaki Shiina 1 1 Department of Urology, Shimane University Faculty of Medicine, Enya-cho, Izumo, Japan 2 Department of Urology, San Francisco Veterans Affairs Medical Center and University of California San Francisco, San Francisco, California, USA 3 Department of Oral Biology, Yonsei University College of Densitry, Seoul, South Korea 4 Department of Urology, Osaka University Graduate School of Medicine, Suita, Japan Correspondence to: Yozo Mitsui, email: // Keywords : bone morphogenetic protein 2, renal cell carcinoma, DNA methylation, molecular marker Received : January 15, 2015 Accepted : February 10, 2015 Published : March 07, 2015 Abstract We investigated whether impaired regulation of bone morphogenetic protein-2 (BMP-2) via epigenetic pathways is associated with renal cell carcinoma (RCC) pathogenesis. Expression and CpG methylation of the BMP-2 gene were analyzed using RCC cell lines, and 96 matched RCC and normal renal tissues. We also performed functional analysis using BMP-2 restored RCC cells. A significant association of BMP-2 mRNA expression was also found with advanced tumor stage and lymph node involvement, while lower BMP-2 mRNA expression was significantly associated with poor overall survival after radical nephrectomy. In RCC cells, BMP-2 restoration significantly inhibited cell proliferation, migration, invasion, and colony formation. In addition, BMP-2 overexpression induced p21 WAF1/CIP1 and p27 KIP1 expression, and cellular apoptosis in RCC cells. BMP-2 mRNA expression was significantly enhanced in RCC cells by 5-aza-2’-deoxycitidine treatment. The prevalence of BMP-2 promoter methylation was significantly greater and BMP-2 mRNA expression was significantly lower in RCC samples as compared to normal kidney samples. Furthermore, a significant correlation was found between BMP-2 promoter methylation and mRNA transcription in tumors. Aberrant BMP-2 methylation and the resultant loss of BMP-2 expression may be a useful molecular marker for designing improved diagnostic and therapeutic strategies for RCC.

We investigated the clinical significance of chromogranin A (CgA) expression as a neuroendocrine (NE) marker during prostate cancer (PCa) progression, especially as a potential predictor of chemotherapeutic response in castration-resistant PCa (CRPC) patients based on immunohistochemical findings.Sixteen CRPC patients who underwent combination (docetaxel/estramustine/ carboplatin; DEC) chemotherapy were retrospectively studied. Immunostaining of CgA was performed using prostate biopsy samples obtained at the initial PCa diagnosis, during androgen deprivation therapy, at the time of CRPC diagnosis, and after 2 cycles of DEC therapy. The positive rate was expressed as the mean percentage of positively stained tumor cells against the total number of tumor cells. Differences in positive rates among the treatment courses were compared using a Mann-Whitney test.The mean percentage of CgA-positive PCa cells increased in a stepwise manner until CRPC development and then significantly decreased after DEC therapy. Subanalysis of CgA at CRPC diagnosis showed a more evident reduction of CgA expression after DEC therapy in patients who also had a high level of CgA as compared to those with a low CgA level (P = .003). Likewise, longer prostate-specific antigen progression-free survival was related to CRPC and high CgA (P = .028).NE differentiation of PCa cells is accelerated despite androgen deprivation and reaches a peak at the time of CRPC diagnosis. Although further studies using larger samples are needed, CgA expression in CRPC may be a candidate tissue biomarker to reflect the chemotherapy sensitivity of individual PCa cells.

Background: The expression level of protein G product 9.5 (PGP9.5) is downregulated because of promoter CpG hypermethylation in several tumors. We speculated that impaired regulation of PGP9.5 through epigenetic pathways is associated with the pathogenesis of prostate cancer. Methods: CpG methylation of the PGP9.5 gene was analyzed in cultured prostate cancer cell lines, 226 localized prostate cancer samples from radical prostatectomy cases, and 80 benign prostate hyperplasia (BPH) tissues. Results: Following 5-aza-2′-deoxycytidune treatment, increased PGP9.5 mRNA transcript expression was found in the LNCaP and PC3 cell lines. With bisulfite DNA sequencing, partial methylation of the PGP9.5 promoter was shown in LNCaP whereas complete methylation was found in PC3 cells. After transfection of PGP9.5 siRNA, cell viability was significantly accelerated in LNCaP but not in PC3 cells as compared with control siRNA transfection. Promoter methylation of PGP9.5 was extremely low in only one of 80 BPH tissues, whereas it was found in 37 of 226 prostate cancer tissues. Expression of the mRNA transcript of PGP9.5 was significantly lower in methylation (+) than methylation (−) prostate cancer tissues. Multivariate analysis of biochemical recurrence (BCR) after an radical prostatectomy revealed pT category and PGP9.5 methylation as prognostically relevant. Further stratification with the pT category in addition to methylation status identified a stepwise reduction of BCR-free probability. Conclusion: This is the first clinical and comprehensive study of inactivation of the PGP9.5 gene via epigenetic pathways in primary prostate cancer. Impact: CpG methylation of PGP9.5 in primary prostate cancer might become useful as a molecular marker for early clinical prediction of BCR after radical prostatectomy. Cancer Epidemiol Biomarkers Prev; 21(3); 487–96. ©2012 AACR.

Introduction and Objective Bone morphogenetic protein-2 (BMP-2) has been shown to function as a tumor suppressor with several different cancers, while its expression level is down-regulated by CpG hypermethylation. We hypothesized that impaired regulation of BMP-2 through epigenetic pathways is associated with the pathogenesis of renal cell carcinoma (RCC). Methods To test our hypothesis, CpG methylation of the BMP-2 gene was analyzed using 2 RCC cell lines, and 96 matched RCC and normal renal tissues. We also performed functional analysis using BMP-2 restored RCC cells. Results BMP-2 mRNA expression was significantly enhanced in the RCC cells by 5-aza-2′-deoxycitidie treatment. The prevalence of BMP-2 promoter methylation was significantly higher, while BMP-2 mRNA expression was significantly lower in RCC samples as compared to normal kidney samples. Furthermore, a significant correlation was found between BMP-2 promoter methylation and mRNA transcription in the tumors. There was also a significant association of BMP-2 mRNA expression with tumor stage and lymph node involvement, while lower BMP-2 mRNA expression was significantly associated with poor overall survival after a radical nephrectomy. In RCC cells, BMP-2 restoration significantly inhibited cell proliferation, migration, invasion, and colony formation. In addition, BMP-2 overexpression effectively induced p21WAF1/CIP1 and p27KIP1 expression, and cellular apoptosis in RCC cells. Conclusion This is the first study to show inactivation of the BMP-2 gene via epigenetic pathways in RCC. Aberrant BMP-2 methylation and the resultant loss of BMP-2 expression may be useful as a molecular marker for designing improved diagnostic and therapeutic strategies for RCC. Citation Format: Yozo Mitsui, Hiroshi Hirata, Naoko Arichi, Miho Hiraki, Hiroaki Yasumono, Inik Chang, Shinichiro Fukuhara, Soichiro Yamamura, Varahram Shahryari, Guoren Deng, Sharanjot Saini, Shahana Majid, Yuichiro Tanaka, Rajvir Dahiya, Hiroaki Shiina. Dysregulation of bone morphogenetic protein 2 serves as a candidate molecular marker in human renal cell carcinoma. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3823. doi:10.1158/1538-7445.AM2015-3823

The precise mechanism of heterotopic ossification caused by several types of tumours is largely unknown. However, recent studies have indicated that bone morphogenetic protein 2 (BMP2) is closely linked to the Wnt/β-catenin signaling pathway in this rare phenomenon of bone formation. We report a rare case of adrenal myelolipoma (ML) in a 27-year-old woman with heterotopic bone formation. Immunohistochemical findings showed BMP2 expression in the cytoplasm of tumour cells, as well as the matrix adjacent to newly developed bone tissue. In addition, β-catenin was prominent in the cytoplasm and nuclei of BMP2-positive tumour cells. To the best of our knowledge, this is the first report of adrenal ML showing heterotopic ossification with accelerated expression of both BMP2 and β-catenin. Our case findings indicate that BMP2 overexpression via aberrant canonical Wnt/β-catenin signaling may contribute to heterotopic bone formation occurring in adrenal ML.

Background Cytochrome P450 1B1 (CYP1B1) has been shown to be up-regulated in many types of cancer including renal cell carcinoma (RCC). Several reports have shown that CYP1B1 can influence the regulation of tumor development; however, its role in RCC has not been well investigated. The aim of the present study was to determine the functional effects of CYP1B1 gene on tumorigenesis in RCC. Methods Expression of CYP1B1 was determined in RCC cell lines, and tissue microarrays of 96 RCC and 25 normal tissues. To determine the biological significance of CYP1B1 in RCC progression, we silenced the gene in Caki-1 and 769-P cells by RNA interference and performed various functional analyses. Results First, we confirmed that CYP1B1 protein expression was significantly higher in RCC cell lines compared to normal kidney tissue. This trend was also observed in RCC samples (p Conclusions CYP1B1 may promote RCC development by inducing CDC20 expression and inhibiting apoptosis through the down-regulation of DAPK1. Our results demonstrate that CYP1B1 can be a potential tumor biomarker and a target for anticancer therapy in RCC.