National Cancer Institute®
Last Modified: July 1, 2002
UI - 11598449
AU - Suzuki S; Tadakuma T; Kunitomi M; Takayama E; Sato M; Asano T; Nakamura
TI - H; Hayakawa M Liposome-mediated gene therapy using HSV-TK/ganciclovir under the control of human PSA promoter in prostate cancer cells.
SO - Urol Int 2001;67(3):216-23
AD - Department of Urology, National Defense Medical College, 302 Namiki, Tokorozawa, Saitama 359-8513, Japan. firstname.lastname@example.org
To more accurately determine the tissue-specific expression of the target gene in prostate cancer cells, we introduced the enhancer element (-4,777 to -3,934; PSAR) and the promoter region (PSAP) of the prostate-specific antigen (PSA) gene. Furthermore, to elucidate the advantages of using liposomes as a gene carrier, we screened more than 20 liposome preparations in this study. The 5' upstream region of PSA gene (PSARPSAP) was conjugated to either the chloramphenicol acetyltransferase (CAT) gene or herpes simplex virus thymidine kinase (TK) gene, and the transfection of these plasmids was carried out using cationic liposomes, DMRIE-C (Gibco) or LipoTAXI (Stratagene). The expression of CAT activity was clearly observed when PSARPSAP-CAT plasmid was transfected into PSA-positive LNCaP cells, whereas no CAT activity was detected in PSA-negative DU145 cells or bladder carcinoma T24 cells. The CAT activity increased after the addition of testosterone. We then evaluated the therapeutic effect of the PSARPSAP-TK plasmid in vitro. When PSARPSAP-TK plasmid was transfected and ganciclovir was added to the medium, the growth of LNCaP cells was inhibited, while no growth inhibition was observed in DU145 cells. Furthermore, this inhibitory effect was observable even when the cells were cultured in a medium supplemented with dialyzed fetal bovine serum. These results suggest that the liposome-mediated transfection of PSARPSAP-TK appears to be a potentially effective approach for selecting the optimal treatment for tumor cells producing PSA even with the low androgen levels seen in patients treated by anti-androgen therapy. Copyright 2001 S. Karger AG, Basel
UI - 11866981
AU - Wang Z; Lai FM; Zhang J
TI - [Analysis of loss of heterozygosity on chromosome 6 in human prostate carcinoma and prostatic intraepithelial neoplasia]
SO - Zhonghua Bing Li Xue Za Zhi 2001 Dec;30(6):414-7
AD - Department of Pathology, Affiliated Zhongda Hospital of Southeast University, Nanjing 210009, China. email@example.com
OBJECTIVE: To detect the significance of loss of heterozygosity (LOH) on chromosome 6 in prostate carcinoma and high grade prostatic intraepithelial neoplasia (PIN). METHODS: Pure DNA was obtained from prostate neoplasms and normal tissues after tissue microdissection. LOH of chromosome 6 was detected by PCR based microsatellite polymorphism analysis technique using 20 pairs of microsatellite primers in 10 prostate carcinoma cases and 10 high grade PIN cases. RESULTS: Allelic loss at one or more loci was observed on chromosome 6 in 8 of 10 prostate carcinoma cases. 6q21-6q23 and 6q25-6q27 were two of LOH high frequency regions. 5 high grade PIN cases had LOH detected on chromosome 6. CONCLUSIONS: Two high frequency LOH regions were detected on chromosome 6 of prostate carcinoma. Cyclin C, IGF2R genes were two candidate tumor suppressor genes located in these two regions, they may be involved in the initiation and progression of prostate cancer.
UI - 11786427
AU - Savinainen KJ; Saramaki OR; Linja MJ; Bratt O; Tammela TL; Isola JJ;
TI - Visakorpi T Expression and gene copy number analysis of ERBB2 oncogene in prostate cancer.
SO - Am J Pathol 2002 Jan;160(1):339-45
AD - Laboratory of Cancer Genetics, Institute of Medical Technology, University of Tampere, Tampere, Finland.
An anti-ERBB2 antibody, trastuzumab, has been shown to be highly efficient in the treatment of metastatic breast cancers overexpressing the ERBB2 gene. It has been suggested that overexpression and even amplification of ERBB2 may play a role in the development of prostate cancer. Here, we have analyzed gene copy number and expression of the ERBB2 gene in both androgen-dependent primary and metastatic tumors, as well as recurrent hormone-refractory tumors. The expression levels were compared to the expression of ERBB2 in breast cancers with or without ERBB2 gene amplification. Of 126 prostate tumors, chromogenic in situ hybridization (CISH) revealed only 1 case containing borderline (six to eight copies) amplifications of ERBB2. This hormone-refractory tumor, however, did not express ERBB2 protein. Immunohistochemical staining of ERBB2 protein was negative (0 or 1+ intensity) in all prostate samples (n = 124) analyzed. To quantitate the level of ERBB2 mRNA expression in prostate tumors (n = 34) and cell lines (n = 3), as well as in breast tumors (n = 30) and cell lines (n = 16), real-time reverse transcriptase-polymerase chain reaction (LightCycler) methodology was used. The expression level was similar in all prostate tumor types and corresponded to the level of expression in breast carcinomas without ERBB2 amplification. Breast tumors with ERBB2 amplification expressed, on average, approximately 20 times (P < 0.001) higher mRNA levels than prostate tumors or breast carcinomas without the gene amplification. In conclusion, the expression of ERBB2 in prostate cancer is relatively low, and is not altered during disease progression. Thus, it is unlikely that treatment modalities relying on the overexpression of ERBB2 gene will be useful in treating prostate cancer.
UI - 12047956
AU - Abate-Shen C; Shen MM
TI - Mouse models of prostate carcinogenesis.
SO - Trends Genet 2002 May;18(5):S1-5
AD - Center for Advanced Biotechnology and Medicine, Department of Neuroscience, UMDNJ-Robert Wood Johnson Medical School, 679 Hoes Lane, Piscataway, NJ 08854, USA. firstname.lastname@example.org
In recent years, numerous mouse models have been generated that recapitulate salient features of prostate carcinogenesis in humans. Here we review progress in the generation and validation of mouse models for prostate cancer, discuss current limitations of these models, and highlight directions of future research.
UI - 12019181
AU - Liu JW; Chandra D; Tang SH; Chopra D; Tang DG
TI - Identification and characterization of Bimgamma, a novel proapoptotic BH3-only splice variant of Bim.
SO - Cancer Res 2002 May 15;62(10):2976-81
AD - Department of Carcinogenesis, the University of Texas M. D. Anderson Cancer Center, Science Park Research Division, Park Road 1C, Smithville, TX 78957, USA.
BH3 (Bcl-2 homology 3)-only proteins of the Bcl-2 family play an essential role in apoptosis. In this study, a novel human BH3-only protein, Bcl-2-interacting mediator (Bim)gamma, was identified during our study of regulation of prostate cancer cell death by Bcl-2 family proteins. Bimgamma shares the highest amino acid sequence homology to BimEL and BimL, two proapoptotic BH3-only Bcl-2 proteins derived from alternative mRNA splicing. Genomic studies indicate that Bimgamma is a novel splice variant of Bim and is generated as a result of the retention of a 126-bp intron of the bim gene. Bimgamma mRNA displays a tissue-specific expression pattern distinct from those of the other Bim isoforms. Subcellular fractionation studies indicate that Bimgamma is localized both in intracellular membranes and cytosol. Interestingly, Bimgamma mRNA, similar to the BimEL protein, is up-regulated in the majority of the prostate cancer cell lines studied, whereas several other proapoptotic Bcl-2 proteins, including Bax, Bak, and Bad, are down-regulated in prostate cancer cells. Functional studies indicate that Bimgamma inhibits clonal growth in prostate cancer cells and promotes apoptosis, which is inhibited by overexpressing Bcl-2. Because both Bimgamma and BimEL are proapoptotic BH3-only proteins and both are up-regulated in prostate cancer cells, they may play a unique role in prostate cancer development.
UI - 11684838
AU - Eder IE; Culig Z; Putz T; Nessler-Menardi C; Bartsch G; Klocker H
TI - Molecular biology of the androgen receptor: from molecular understanding to the clinic.
SO - Eur Urol 2001 Sep;40(3):241-51
AD - Department of Urology, University of Innsbruck, Austria.
The androgen receptor (AR) is the key regulatory element of androgen signaling in the cell. It mediates action of androgens and is therefore essential for growth, function and differentiation of the human male urogenital tract. Genetic alterations in the AR gene may cause impaired development resulting in androgen insensitivity syndromes (AIS) or in neurodegenerative diseases like Kennedy syndrome. Besides the crucial role in the process of virilization during embryogenesis and puberty, the AR also plays an important role in the adult man as the intracellular mediator of androgen action. Androgen withdrawal and/or AR blockade is the main choice of treatment of nonorgan-confined prostate cancer. Unfortunately, this treatment is only palliative and a majority of these tumors recur and progress to an androgen-independent and therapy-resistant stage. Recent findings gave new insight into the molecular structure and function of the AR and improved our understanding about prostate cancer progression, consequently resulting in the development of novel treatments. It has become evident that the AR is a nuclear transcription factor that can be activated ligand-dependently by androgens as well as ligand-independently by other hormones and various growth factors, respectively. Moreover, it was shown that the interaction of the AR with other proteins of the intracellular signal transduction cascade may promote prostate tumor growth. This review will summarize the most important findings about the AR and the androgen signaling pathway to improve the understanding of prostate diseases and novel treatment strategies that may be useful in the clinic.
UI - 12057920
AU - Ernst T; Hergenhahn M; Kenzelmann M; Cohen CD; Bonrouhi M; Weninger A;
TI - Klaren R; Grone EF; Wiesel M; Gudemann C; Kuster J; Schott W; Staehler G; Kretzler M; Hollstein M; Grone HJ Decrease and gain of gene expression are equally discriminatory markers for prostate carcinoma: a gene expression analysis on total and microdissected prostate tissue.
SO - Am J Pathol 2002 Jun;160(6):2169-80
AD - Department of Cellular and Molecular Pathology, Deutsches Krebsforschungszentrum Heidelberg, Heidelberg, Germany.
Information on over- and underexpressed genes in prostate cancer in comparison to adjacent normal tissue was sought by DNA microarray analysis. Approximately 12,600 mRNA sequences were analyzed from a total of 26 tissue samples (17 untreated prostate cancers, 9 normal adjacent to prostate cancer tissues) obtained by prostatectomy. Hierarchical clustering was performed. Expression levels of 63 genes were found significantly (at least 2.5-fold) increased, whereas expression of 153 genes was decreased (at least 2.5-fold) in prostate cancer versus adjacent normal tissue. In addition to previously described genes such as hepsin, overexpression of several genes was found that has not drawn attention before, such as the genes encoding the specific granule protein (SGP28), alpha-methyl-acyl-CoA racemase, low density lipoprotein (LDL)-phospholipase A2, and the anti-apoptotic gene PYCR1. The radiosensitivity gene ATDC and the genes encoding the DNA-binding protein inhibitor ID1 and the phospholipase inhibitor uteroglobin were significantly down-regulated in the cancer samples. DNA microarray data for eight genes were confirmed quantitatively in five normal and five cancer tissues by real-time reverse transcriptase-polymerase chain reaction with a high correlation between the two methods. Laser capture microdissection of epithelial and stromal compartments from cancer and histological normal specimens followed by an amplification protocol for low levels of RNA (<0.1 microg) allowed us to distinguish between gene expression profiles characteristic of epithelial cells and those typical of stroma. Most of the genes identified in the nonmicrodissected tumor material as up-regulated were indeed overexpressed in cancerous epithelium rather than in the stromal compartment. We conclude that development of prostate cancer is associated with down-regulation as well as up-regulation of genes that show complex differential regulation in epithelia and stroma. Some of the gene expression alterations identified in this study may prove useful in the development of novel diagnostic and therapeutic strategies.
UI - 12089231
AU - Gelmann EP
TI - Molecular biology of the androgen receptor.
SO - J Clin Oncol 2002 Jul 1;20(13):3001-15
AD - Department of Oncology, Lombardi Cancer Center, Georgetown University School of Medicine, 3800 Reservoir Rd NW, Washington, DC 20007-2197, USA. email@example.com
Androgen receptor (AR) is a member of the steroid hormone receptor family of molecules. AR primarily is responsible for mediating the physiologic effects of androgens by binding to specific DNA sequences that influence transcription of androgen-responsive genes. The three-dimensional structure of the AR ligand-binding domain has shown it is similar to other steroid hormone receptors and that ligand binding alters the protein conformation to allow binding of coactivator molecules that amplify the hormone signal and mediate transcriptional initiation. However, AR also undergoes intramolecular interactions that regulate its interactions with coactivators and influence its activity. A large number of naturally occurring mutations of the human AR gene have provided important information about AR molecular structure and intermolecular interactions. AR is also a critical mediator of prostate cancer promotion, conferring growth signals to prostate cancer cells throughout the natural history of the disease. Late-stage prostate cancer, unresponsive to hormonal deprivation, sustains AR signaling through a diverse array of molecular strategies. Variations in the AR gene may also confer genetic predisposition to prostate cancer development and severity. Further understanding of AR action and new strategies to interfere with AR signaling hold promise for improving prostate cancer therapy.
UI - 12036903
AU - Kim MJ; Bhatia-Gaur R; Banach-Petrosky WA; Desai N; Wang Y; Hayward SW;
TI - Cunha GR; Cardiff RD; Shen MM; Abate-Shen C Nkx3.1 mutant mice recapitulate early stages of prostate carcinogenesis.
SO - Cancer Res 2002 Jun 1;62(11):2999-3004
AD - Department of Neuroscience, Center for Advanced Biotechnology and Medicine, 679 Hoes Lane, Piscataway, NJ 08854, USA.
Recent studies of human cancers and mutant mouse models have implicated the Nkx3.1 homeobox gene as having a key role in prostate carcinogenesis. Consistent with such a role, here we show that Nkx3.1 displays growth-suppressing activities in cell culture, and that aged Nkx3.1 mutant mice display histopathological defects resembling prostatic intraepithelial neoplasia (PIN), the presumed precursor of human prostate cancer. Using a tissue recombination approach, we found that PIN-like lesions from Nkx3.1 mutants can undergo progressively severe histopathological alterations after serial transplantation in nude mice. Our findings indicate that Nkx3.1 loss-of-function is a critical event in prostate cancer initiation, and that Nkx3.1 mutant mice accurately model early stages of prostate carcinogenesis. More generally, our tissue recombination assay provides an empirical test to examine the relationship of PIN to prostate carcinoma.
UI - 12036942
AU - Potapova O; Anisimov SV; Gorospe M; Dougherty RH; Gaarde WA; Boheler KR;
TI - Holbrook NJ Targets of c-Jun NH(2)-terminal kinase 2-mediated tumor growth regulation revealed by serial analysis of gene expression.
SO - Cancer Res 2002 Jun 1;62(11):3257-63
AD - Cell Stress and Aging Section, Laboratory of Cellular and Molecular Biology, Gerontology Research Center, National Institute on Aging-IRP/NIH, Baltimore, MD 21224, USA.
Although the c-Jun NH(2)-terminal kinase (JNK) pathway has been implicated in mediating cell growth and transformation, its downstream effectors remain to be identified. Using JNK2 antisense oligonucleotides (JNK2AS), we uncovered previously a role for JNK2 in regulating cell cycle progression and survival of human PC3 prostate carcinoma cells. Here, to identify genes involved in implementing JNK2-mediated effects, we have analyzed global gene expression changes in JNK2-deprived PC3 cells using Serial Analysis of Gene Expression. More than 40,000 tags each were generated from control and PC3-JNK2AS libraries, corresponding to 15,999 and 20,698 unique transcripts, respectively. Transcripts corresponding to transcription factors, stress-induced genes, and apoptosis-related genes were up-regulated in the PC3-JNK2AS library, revealing a significant stress response after the inhibition of JNK2 expression. Genes involved in DNA repair, mRNA turnover, and drug resistance were found to be down-regulated by inhibition of JNK2 expression, further highlighting the importance of JNK2 signaling in regulating cell homeostasis and tumor cell growth.
UI - 12036948
AU - Tuxhorn JA; McAlhany SJ; Dang TD; Ayala GE; Rowley DR
TI - Stromal cells promote angiogenesis and growth of human prostate tumors in a differential reactive stroma (DRS) xenograft model.
SO - Cancer Res 2002 Jun 1;62(11):3298-307
AD - Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX 77030, USA.
Reactive stroma has been reported in many cancers, including breast, colon,and prostate. Although changes in stromal cell phenotype and extracellular matrix have been reported, specific mechanisms of how reactive stroma affects tumor progression are not understood. To address the role of stromal cells in differential regulation of tumor incidence, growth rate, and angiogenesis, LNCaP xenograft tumors were constructed in nude mice with five different human prostate stromal cell lines as well as GeneSwitch-3T3 cells engineered to express lacZ under mifepristone regulation. Alone, LNCaP prostate carcinoma cells were essentially nontumorigenic, whereas combinations of LNCaP cells with three different human prostate stromal cell lines (L/S tumors) resulted in a tumor incidence (50-63%) similar to that of control LNCaP plus Matrigel (L/M) tumors over a 9-week period. In contrast, LNCaP combinations with two other human prostate stromal cell lines were nontumorigenic, illustrating that stromal cell effects are differential. L/S tumors exhibited well-developed blood vessels at 2 weeks, whereas control L/M tumors were avascular at 2 weeks and exhibited blood lakes in lieu of extensive vessels at later time points. Xenografts constructed under three-way conditions (LNCaP, Matrigel, and stromal cells; L/M/S tumors) exhibited a 100% tumor incidence and showed rapid blood vessel formation as early as day 7 with mature vessels formed by day 10. L/M/S tumors exhibited a 10.3-fold increase in microvessel density, and the corresponding hemoglobin:tumor weight ratio was increased 2-fold relative to L/M control tumors at day 10. L/M/S tumor wet weight and volume increased by 1.6- and 2.4-fold, respectively, by day 21, compared with control L/M tumors. L/M/S tumors made with LNCaP cells plus GeneSwitch-3T3-pGene/lacZ stromal cells showed similar results. Mifepristone-regulated gene expression was observed in stromal cells immediately adjacent to clusters of carcinoma cells and in vessel walls in a mural cell (pericyte) position. This study shows that regulation of angiogenesis is one mechanism through which stromal cells affect LNCaP tumor incidence and growth rate. This regulation may be mediated through direct recruitment and interactions of stromal cells with endothelial cells. Furthermore, this study describes for the first time a model system with regulated transgene expression in the stromal compartment of an experimental carcinoma. These findings point to the stromal compartment as a potential source of new prognostic markers and therapeutic targets and show the utility of the carcinoma-stromal xenograft model system in dissecting specific mechanisms of reactive stroma.
UI - 12036949
AU - Asmann YW; Kosari F; Wang K; Cheville JC; Vasmatzis G
TI - Identification of differentially expressed genes in normal and malignant prostate by electronic profiling of expressed sequence tags.
SO - Cancer Res 2002 Jun 1;62(11):3308-14
AD - Division of Experimental Pathology, Department of Laboratory Medicine and Pathology, Mayo Clinic and Foundation, 200 First Street SW, Rochester, MN 55905, USA.
Differentially expressed genes between corresponding normal and cancertissue can advance our understanding of the molecular basis of malignancy and potentially serve as biomarkers or prognostic markers of malignancy. To identify differentially expressed genes in prostate cancer, we used a procedure combining electronic expression profiling of the prostate expressed sequence tag (EST) database and molecular biology techniques. A novel electronic expression-profiling algorithm was developed to search publicly available EST sequences for genes that show significant differential expression in prostate cancer compared with normal prostate tissue. Approximately 600 genes expressed in prostate were identified through adequate EST counts of ESTs for electronic profiling. Of these 600 genes, 9 showed statistically significant differences in their EST counts between cancer and normal prostate and were further analyzed. The predictions associated with electronic profiling were experimentally verified for two genes, cysteine-rich secretory protein 3 (CRISP-3) and deadenylating nuclease (DAN), using real-time reverse transcription-PCR with total RNA extracted from cells isolated by laser capture microdissection. In five of five Gleason score 6 cancer cases, CRISP-3 expression was increased >50 fold, whereas the expression of DAN was reduced by >80%.
UI - 12067976
AU - McCarron SL; Edwards S; Evans PR; Gibbs R; Dearnaley DP; Dowe A;
TI - Southgate C; Easton DF; Eeles RA; Howell WM Influence of cytokine gene polymorphisms on the development of prostate cancer.
SO - Cancer Res 2002 Jun 15;62(12):3369-72
AD - Department of Histocompatibility and Immunogenetics, Southampton University Hospitals NHS Trust, SO16 6YD, United Kingdom.
Polymorphisms in the promoter regions of cytokine genes may influence prostate cancer (PC) development via regulation of the antitumor immune response and/or pathways of tumor angiogenesis. PC patients (247) and 263 controls were genotyped for interleukin (IL)-1beta-511, IL-8-251, IL-10-1082, tumor necrosis factor-alpha-308, and vascular endothelial growth factor (VEGF)-1154 single nucleotide polymorphisms. Patient control comparisons revealed that IL-8 TT and VEGF AA genotypes were decreased in patients compared with controls [23.9 versus 32.3%; P = 0.04, odds ratio (OR) = 0.66, 95% confidence interval (CI) 0.44-0.99 and 6.3 versus 12.9%; P = 0.01, OR = 0.45, 95% CI 0.24-0.86, respectively], whereas the IL-10 AA genotype was significantly increased in patients compared with controls (31.6 versus 20.6%; P = 0.01, OR = 1.78, 95% CI 1.14-2.77). Stratification according to prognostic indicators showed association between IL-8 genotype and log prostate-specific antigen level (P = 0.05). These results suggest that single nucleotide polymorphisms associated with differential production of IL-8, IL-10, and VEGF are risk factors for PC, possibly acting via their influence on angiogenesis.
UI - 12067994
AU - Kuzmin I; Gillespie JW; Protopopov A; Geil L; Dreijerink K; Yang Y;
TI - Vocke CD; Duh FM; Zabarovsky E; Minna JD; Rhim JS; Emmert-Buck MR; Linehan WM; Lerman MI The RASSF1A tumor suppressor gene is inactivated in prostate tumors and suppresses growth of prostate carcinoma cells.
SO - Cancer Res 2002 Jun 15;62(12):3498-502
AD - Intramural Research Support Program, SAIC-Frederick, Inc., National Cancer Institute Frederick, Maryland 21702, USA. firstname.lastname@example.org
We analyzed expression status of the recently identified tumor suppressor geneRASSF1A in primary prostate carcinomas and in prostate cell lines. We found complete methylation of the RASSF1A promoter in 63% of primary microdissected prostate carcinomas (7 of 11 samples). The remaining 4 samples (37%) were partially methylated, possibly because of contamination with normal cells. No promoter methylation was observed in matching normal prostate tissues. High levels of RASSF1A transcript and no methylation of RASSF1A promoter were found in explanted primary normal prostate epithelial and stromal cells. Complete silencing and methylation of RASSF1A promoter was observed in five widely used prostate carcinoma cell lines, which acquired the ability to grow in culture spontaneously, including LNCaP, PC-3, ND-1, DU-145, 22Rv1, and one primary prostate carcinoma immortalized by overexpression of the human telomerase catalytic subunit (RC-58T/hTERT). However, no silencing of RASSF1A was found in four other prostate carcinoma cell lines, which were adapted for cell culture after transformation with human papillomaviral DNA. Suppression of cell growth in vitro was demonstrated after the reintroduction of RASSF1A-expressing construct into LNCaP prostate carcinoma cells. Our data implicate the RASSF1A gene in human prostate tumorigenesis.
UI - 11847075
AU - Ghosh D; Chinnaiyan AM
TI - Mixture modelling of gene expression data from microarray experiments.
SO - Bioinformatics 2002 Feb;18(2):275-86
AD - Department of Biostatistics, School of Public Health, University of Michigan, 1420 Washington Heights, Room M4057, Ann Arbor, MI 48109-2029, USA. email@example.com
MOTIVATION: Hierarchical clustering is one of the major analytical tools for gene expression data from microarray experiments. A major problem in the interpretation of the output from these procedures is assessing the reliability of the clustering results. We address this issue by developing a mixture model-based approach for the analysis of microarray data. Within this framework, we present novel algorithms for clustering genes and samples. One of the byproducts of our method is a probabilistic measure for the number of true clusters in the data. RESULTS: The proposed methods are illustrated by application to microarray datasets from two cancer studies; one in which malignant melanoma is profiled (Bittner et al., Nature, 406, 536-540, 2000), and the other in which prostate cancer is profiled (Dhanasekaran et al., 2001, submitted).
UI - 11906253
AU - Benimetskaya L; Guzzo-Pernell N; Liu ST; Lai JC; Miller P; Stein CA
TI - Protamine-fragment peptides fused to an SV40 nuclear localization signal deliver oligonucleotides that produce antisense effects in prostate and bladder carcinoma cells.
SO - Bioconjug Chem 2002 Mar-Apr;13(2):177-87
AD - Howard Florey Institute of Experimental Physiology and Medicine, University of Melbourne, Parkville, Victoria, 3052, Australia.
The development of antisense technology has focused on improving methods for oligonucleotide delivery into cells. In the present work, we describe a novel strategy for oligonucleotide delivery based on a bifunctional peptide composed of a C-terminal protamine-fragment that contains a DNA-binding domain and an N-terminal nuclear localization signal sequence derived from the SV40 large-T antigen (The sequences of two of the peptides are R6WGR6-PKKKRKV [s-protamine-NLS] and R4SR6FGR6VWR4-PKKKRKV [l-protamine-NLS]). We demonstrated, by intrinsic fluorescence quenching, that peptides of this class form complexes with oligodeoxynucleotides. To evaluate delivery, we used a 20-mer phosphorothioate oligomer (Isis 3521) targeted to the 3'-untranslated region of the PKC-alpha mRNA and G3139, an 18-mer phosphorothioate targeted to the first six codons of the human bcl-2 open reading frame, and complexed them with either of two peptides (s- or l-protamine-NLS). These peptides bind to and deliver antisense oligonucleotides to the nucleus of T24 bladder and PC3 prostate cancer cells, as demonstrated by confocal microscopy. Furthermore, as shown by Western and Northern blotting, the peptide-oligonucleotide complexes produced excellent downregulation of the expression of the complementary mRNAs, which in turn resulted in downregulation of protein expression. However, under certain circumstances (predominantly in PC3 cells), incubation of the cells with chloroquine was required to produce antisense activity. Using this strategy, PKC-alpha protein and mRNA expression in T24 and PC3 cells and bcl-2 expression in PC3 cells was reduced by approximately 75 +/- 10% at a minimum concentration of oligomer of 0.25 microM, in combination with 12-15 microM peptide. On the basis of our results, we conclude that arginine-rich peptides of this class may be potentially useful delivery vehicles for the cellular delivery of antisense oligonucleotides. This new strategy may have several advantages over other methods of oligonucleotide delivery and may complement already existing lipid-based technologies.
UI - 12010866
AU - Gsur A; Preyer M; Haidinger G; Schatzl G; Madersbacher S; Marberger M;
TI - Vutuc C; Micksche M A polymorphism in the UDP-Glucuronosyltransferase 2B15 gene (D85Y) is not associated with prostate cancer risk.
SO - Cancer Epidemiol Biomarkers Prev 2002 May;11(5):497-8
AD - Division of Applied and Experimental Oncology, Institute of Cancer Research, University of Vienna, Austria. firstname.lastname@example.org
UI - 12050097
AU - Perez-Stable CM; Schwartz GG; Farinas A; Finegold M; Binderup L; Howard
TI - GA; Roos BA The G gamma / T-15 transgenic mouse model of androgen-independent prostate cancer: target cells of carcinogenesis and the effect of the vitamin D analogue EB 1089.
SO - Cancer Epidemiol Biomarkers Prev 2002 Jun;11(6):555-63
AD - Geriatric Research, Education, and Clinical Center and Research Service, Veterans Affairs Medical Center, Miami, Florida 33125, USA. email@example.com
Transgenic mouse models of prostate cancer provide unique opportunities to understand the molecular events in prostate carcinogenesis and for the preclinical testing of new therapies. We studied the G gamma T-15 transgenic mouse line, which contains the human fetal globin promoter linked to SV40 T antigen (Tag) and which develops androgen-independent prostate cancer. Using the immunohistochemistry of normal mouse prostates before tumor formation, we showed that the target cells of carcinogenesis in G gamma T-15 mice are located in the basal epithelial layer. We tested the efficacy of the 1,25(OH)(2)D(3) analogue, EB 1089, to chemoprevent prostate cancer in these transgenic mice. Compared with treatment with placebo, treatment with EB 1089 at three different time points before the onset of prostate tumors in mice did not prevent or delay tumor onset. However, EB 1089 significantly inhibited prostate tumor growth. At the highest dose, EB 1089 inhibited prostate tumor growth by 60% (P = 0.0003) and the growth in the number of metastases, although this dose also caused significant hypercalcemia and weight loss. We conducted several in vitro experiments to explore why EB 1089 did not prevent the occurrence of the primary tumors. EB 1089 significantly inhibited the growth of a Tag-expressing human prostate epithelial cell line, BPH-1, and an androgen-insensitive subline of LNCaP cells [which was not inhibited by 1,25(OH)(2)D(3)]. Thus, neither Tag expression nor androgen insensitivity explain the absence of chemopreventive effect. Conversely, neither 1,25(OH)(2)D(3) nor EB 1089 inhibited the growth of the normal rat prostate basal epithelial cell line NRP-152. It is likely that EB 1089 was not effective in delaying the growth of the primary tumor in G gamma T-15 transgenic mice because the target cells of carcinogenesis in these mice are located in the basal epithelial layer. We conclude that G gamma T-15 transgenic mice are a useful model for testing vitamin D-based therapies in androgen-insensitive prostate cancer but are not suitable for studies of vitamin D-based chemoprevention. The superiority of EB 1089 over 1,25(OH)(2)D(3) in the growth suppression of androgen-insensitive prostate cancer cells supports the use of EB 1089 in androgen-insensitive prostate cancer.
UI - 12087071
AU - Lentsch AB
TI - The Duffy antigen/receptor for chemokines (DARC) and prostate cancer. A role as clear as black and white?
SO - FASEB J 2002 Jul;16(9):1093-5
AD - Department of Surgery, University of Cincinnati College of Medicine, Cincinnati, Ohio 45267-0558, USA. firstname.lastname@example.org
Prostate cancer is the most commonly diagnosed cancer and the second leading cause of cancer-related death among men in the United States. African American men have a 60% greater incidence of prostate cancer and a twofold higher mortality rate than Caucasian men. The Duffy antigen/receptor for chemokines (DARC) is a receptor expressed on erythrocytes and vascular endothelial cells that binds to and clears angiogenic chemokines. The DARC also functions as the erythrocyte receptor for invasion by malarial parasites. Approximately 70% of African Americans lack erythrocyte expression of the DARC as a genetic mechanism of protection against malaria infection. Given the importance of angiogenic chemokines in the development of tumor vascular networks and the chemokine binding properties of the DARC, the possibility that a lack of DARC expression on erythrocytes may represent an epigenetic factor that predisposes African American men to a greater incidence and mortality of prostate cancer should be considered.
UI - 11827168
AU - Wang H; Davis A; Yu S; Ahmed K
TI - Response of cancer cells to molecular interruption of the CK2 signal.
SO - Mol Cell Biochem 2001 Nov;227(1-2):167-74
AD - Department of Laboratory Medicine and Pathology and University of Minnesota Cancer Center, University of Minnesota, Minneapolis, USA.
Protein kinase CK2 is one of the key cellular signals for cell survival, growth, and proliferation. It is has been observed to be elevated in various cancers that have been examined. Various observations suggest that moderate dysregulation of CK2 may profoundly influence the cell response. We have examined the effects of interfering with the CK2 signal in various cancer cell lines by employing antisense oligodeoxynucleotides (ODN) against the alpha and beta subunits of CK2. Our results demonstrate that antisense CK2-alpha and antisense CK2-beta ODNs markedly influence cell viability of these cancer cells in a dose and time-dependent manner. Antisense CK2-alpha was slightly more effective than antisense CK2-beta in most of the cells tested. The efficacy of the antisense ODN seemed to vary with the cell type; however, in all cases potent induction of apoptosis was observed. Significantly, the effects of the antisense ODN on the CK2 activity in the nuclear matrix were relatively small compared to the much stronger induction of apoptosis in cells. This suggests that modest downregulation of CK2 can evoke a much greater apoptotic response in cancer cells.
UI - 12083956
AU - Culig Z; Klocker H; Bartsch G; Hobisch A
TI - Androgen receptor mutations in carcinoma of the prostate: significance for endocrine therapy.
SO - Am J Pharmacogenomics 2001;1(4):241-9
AD - Department of Urology, University of Innsbruck, Innsbruck, Austria. email@example.com
Endocrine therapy for advanced prostate cancer involves androgen ablation (orchiectomy or application of luteinizing hormone releasing hormone analogs) and/or blockade of the androgen receptor (AR) with either steroidal (cyproterone acetate) or nonsteroidal (hydroxyflutamide, bicalutamide and nilutamide) antiandrogens. These antagonists prevent androgen-induced conformational change and activation of the AR. During long term androgen ablation, the AR adapts to an environment with low androgen concentrations and becomes hypersensitive to low concentrations of androgens, either alone or in combination with various cellular regulators. Bicalutamide can switch from antagonist to agonist during long-term androgen withdrawal, as shown in prostate cancer LNCaP cells. AR point mutations were detected in metastatic lesions from human prostate cancer more frequently than in primary tumors. Although functional characterization of only some mutant AR detected in prostate cancer tissue has been performed, data available suggest that they are activated by dihydrotestosterone, its precursors and metabolites, synthetic androgens, estrogenic and progestagenic steroids and hydroxyflutamide. A direct association between AR mutations and endocrine withdrawal syndrome has been investigated in only one study thus far. There is no evidence at present that activation of any of the mutant AR genes detected in prostate cancer is enhanced in the presence of a nonsteroidal AR stimulator. Coactivators of the AR are proteins that associate with the receptor, possess histone acetylase activity and facilitate AR activation. The coregulatory proteins ARA70 and ARA160 differentially affected the activity of the mutated AR Glu(231)-->Gly, which was discovered in a mouse authochthonous prostate tumor. ARA70 enhanced receptor activation by both androgen and estradiol, whereas ARA160 augmented only androgen-induced AR activity. Novel experimental therapies that down-regulate AR expression have been developed; they include the application of ribozymes and antisense oligonucleotides.
UI - 12084298
AU - Li PE; Nelson PS
TI - Prostate cancer genomics.
SO - Curr Urol Rep 2001 Feb;2(1):70-8
AD - Division of Human Biology, Fred Hutchinson Cancer Research Center, 1100 Fairview Avenue North, Mailstop D4-100, Seattle, WA 98109-1024, USA. firstname.lastname@example.org
The molecular processes contributing to cancer of the human prostate gland are under intensive investigation. Methods used for discovering genetic alterations involved in prostate neoplasia include family studies designed to map hereditary disease loci, chromosomal studies to identify aberrations that may locate oncogenes or tumor suppressor genes, and comprehensive gene expression studies. These studies determine how various molecular signaling pathways influence or reflect the process of carcinogenesis. However, a comprehensive overview of the cell is necessary to understand all of the dynamic interactions between genes, their protein products, and the network of cellular processes resulting in tumorigenesis. Unraveling the complexity of these systems in a timely manner involves the integration of computers, miniaturization, and automation into molecular biology. New biotechnologies such as the development of automated DNA sequencing and complementary DNA microarrays allow for a systematic, "discovery-driven" approach. These and other technologies afford a comprehensive view of biology and pathology that have the potential to fully characterize the processes involved in neoplasia and therefore provide potential targets for the therapy of prostate and other cancers.
UI - 12084265
AU - Gingrich JR; Chauhan RD; Steiner MS
TI - Gene therapy for prostate cancer.
SO - Curr Urol Rep 2001 Jun;2(3):199-208
AD - Department of Urology, University of Tennessee Medical Center, 956 Court Avenue, H216, Memphis, TN 38163, USA. Jgingrich@utmem.edu
Basic research continues to unravel the molecular complexity of normal and abnormal biologic processes. The development of means to affect the expression level of genes that promote or contribute to cellular transformation, invasion, and metastasis has spawned the concept of gene therapy. This relatively new field seeks to reverse or suspend the pathologic progression of a variety of diseases including the malignant transformation of prostatic epithelial cells. Initial clinical trials for prostate cancer have thus far shown gene therapy to be relatively safe, although definitive evidence of durable therapeutic efficacy remains to be demonstrated. In this article, recent preclinical research, current therapeutic strategies, and recent results of gene therapy clinical trials for the treatment of prostate cancer are reviewed.
UI - 12022038
AU - Wang L; McDonnell SK; Elkins DA; Slager SL; Christensen E; Marks AF;
TI - Cunningham JM; Peterson BJ; Jacobsen SJ; Cerhan JR; Blute ML; Schaid DJ; Thibodeau SN Analysis of the RNASEL gene in familial and sporadic prostate cancer.
SO - Am J Hum Genet 2002 Jul;71(1):116-23
AD - Department of Laboratory Medicine, Mayo Clinic and Foundation, Rochester, MN 55905, USA.
The RNASEL gene on chromosome 1q25 was recently identified as a candidate gene for hereditary prostate cancer (PC). To confirm these findings, we screened 326 patients from 163 families with familial PC for potential germline mutations, by use of conformation-sensitive gel electrophoresis, followed by direct sequence analysis. A total of six variants were identified, including one intronic and five exonic changes (three missense and two silent alterations). There were no unequivocal pathogenic changes. To further test for potential associations between genes and increased risk for disease, the three missense polymorphisms (Ile97Leu, Arg462Gln, and Glu541Asp) were genotyped in 438 patients with familial PC and in 510 population-based control subjects. Association testing revealed no significant differences between patients and control subjects for either the Leu97 variant (chi(2) trend test = 1.42; P=.23) or the Asp541 variant (chi2=1.52; P=.22). However, significant differences were detected for the Arg462Gln genotypes (chi2=5.20; P=.02; odds ratio [OR] = 0.54; 95% confidence interval [CI] 0.32-0.91) when the genotype Gln/Gln was compared with Arg/Arg. In subset analyses, associations were also observed in the younger group (age at diagnosis =64 years) (P=.0008; OR=0.29; 95% CI = 0.13-0.66), in node-negative patients (P=.01; OR=0.48; 95% CI 0.27-0.84), patients with stage T(1)/T(2) disease (P=.008; OR=0.39; 95% CI 0.2-0.75), and patients with low-grade disease (P=.01; OR=0.40; 95% CI 0.20-0.78). To evaluate whether this variant was also associated with sporadic PC, we genotyped an additional 499 patients with sporadic PC. Differences in frequency were not detected between patients with sporadic disease and control subjects. However, the same association was observed between patients with familial disease and patients with sporadic disease for the entire group (chi2=4.82; P=.03), as well as in the subset analyses. These results suggest that polymorphic changes within the RNASEL gene may be associated with increased risk of familial but not sporadic PC.
UI - 12101412
AU - Gery S; Sawyers CL; Agus DB; Said JW; Koeffler HP
TI - TMEFF2 is an androgen-regulated gene exhibiting antiproliferative effects in prostate cancer cells.
SO - Oncogene 2002 Jul 18;21(31):4739-46
AD - Division of Hematology/Oncology, Cedars-Sinai Medical Center, Los Angeles, California, CA 90048, USA. email@example.com
We have identified a gene that is highly expressed in the androgen-dependent prostate cancer cell line, LNCaP. Sequence analysis revealed that it was identical to a recently cloned gene designated TMEFF2, which encodes a transmembrane protein containing an epidermal growth factor (EGF)-like motif and two follistatin domains. This gene was highly expressed only in primary samples of normal prostate and prostate cancer as well as normal brain. Expression of the gene was controlled by androgen as shown by dihydrotestosterone markedly increasing TMEFF2 expression in LNCaP cells. Also, androgen-dependent human prostate cancer xenografts (CWR22) expressed high levels of TMEFF2 and these levels markedly decreased by day 10 after castration of the mice. Furthermore, a large number of androgen-dependent xenografts (CWR22, LuCaP-35, LAPC-4AD, LAPC-9AD) exhibited higher levels of TMEFF2 mRNA than androgen-independent xenografts (CWR22R, LAPC-3AI, LAPC-4AI, LAPC-9AI). Ectopic expression of TMEFF2 in DU145 and PC3 cells resulted in their prominent inhibition of growth. Taken together, the results demonstrate that TMEFF2 is a androgen-regulated gene, which can suppress growth of prostate cancer cells and our xenograft data show that escape of prostate cancer cells from androgen modulation causes them to decrease their expression of this gene, which may result in their more malignant behavior.
UI - 11693894
AU - Stern DF
TI - HER-2 testing in prostate carcinoma.
SO - Cancer J 2001 Sep-Oct;7(5):372-4
AD - Department of Pathology, Yale University School of Medicine, New Haven, Connecticut 06510, USA.
UI - 11693898
AU - Liu HL; Gandour-Edwards R; Lara PN Jr; de Vere White R; LaSalle JM
TI - Detection of low level HER-2/neu gene amplification in prostate cancer by fluorescence in situ hybridization.
SO - Cancer J 2001 Sep-Oct;7(5):395-403
AD - Department of Internal Medicine, University of California, San Francisco, USA.
PURPOSE: Although expression of the HER-2/neu oncogene has been correlated with tumor progression in prostate cancer, the biologic significance of detecting HER-2/neu gene amplification by fluorescence in situ hybridization (FISH) or evidence for protein overexpression by immunohistochemistry (IHC) remains unclear. In this study, we directly compared HER-2/neu FISH and IHC to determine which may be more predictive of the response to trastuzumab. PATIENTS AND METHODS: Forty patients with prostate cancer were analyzed for gene amplification by FISH performed with HER-2/neu and chromosome 17 (CEP 17) DNA probes (Vysis). Protein expression was examined by immunofluorescence and by IHC using the DAKO HercepTest antibody protocol and a monoclonal antibody to Her-2/neu on archival paraffin sections. The patients included 30 men with primary tumors that were treated with radical prostatectomy. Of these, 15 demonstrated subsequent disease progression within 3 years. Five patients with prostatic intraepithelial neoplasia were tested, as were five with metastatic disease whose samples were obtained before androgen ablation therapy. RESULTS: None of the 30 primary prostate cancer specimens showed overexpression for HER-2/neu by immunofluorescence or by IHC with the DAKO protocol. One sample showed 3+ membrane expression with the monoclonal antibody. In contrast, low copy number gene amplifications (3-8 HER-2/neu signals/nucleus) were detected in 16 of 30 samples (53%) by FISH. Most amplified cells were diploid for CEP 17, demonstrating that amplification was not due to total cell aneuploidy. FISH and IHC determined that prostatic intraepithelial neoplasia samples were normal. Four of five (80%) metastatic samples were amplified for HER-2/neu by FISH. Nearly 70% of metastatic cancer cells among all five specimens demonstrated aneuploidy. A single lymph node metastasis showed 3+ membrane stain