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Prostate cancer is one of the common malignant tumors of male urogenital system, and the incidence of prostate cancer in China has increased significantly in the past decade. At present, endocrine therapy based on androgen blockade is the main method of clinical treatment except radical surgery and radiotherapy/chemotherapy for prostate cancer. However, the clinical benefit can only be obtained in the early stage of treatment, and nearly 90% of patients will develop to the castration resistance, and among them, nearly 90% of patients will have bone metastasis. The quality of life decreases sharply with the progression of disease for patients. In addition to the androgen signal pathway, studies have shown that many other oncogenic signal pathways have involved in the development of castration resistance, including classic cancer signaling pathways, immune and inflammatory signaling pathways, etc. Understanding the mechanism of androgen independent signal pathway in the formation of castration resistance will help to understand the off-target effect of androgen blocking therapy and introduce new treatment targets or strategies to get rid of the "no drug available" dilemma for clinical treatment of castration resistance.
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Objective To synthesize a novel prostate cancer targeting gene vector PAMAM-PEG-C2min and improve gene transfection efficiency targeting on prostate cancer. Methods The aptamer (C2min) and polyamide-amine (PAMAM) were ligated by polyethylene glycol (PEG). The structure of the synthesized PAMAM-PEG-C2min was identified by NMR. The biological characteristics of the nanoparticles were examined by the uptake experiments and gene transfection experiments (the loaded gene was siR-M) with the prostate cancer cells (PC3 and LNCaP). Besides, the in vivo targeting was investigated using in vivo image system. The in vivo targeting results indicated that PAMAM-PEG-C2min can achieve the simultaneous targeting of two prostate cancer tissues. Results The PAMAM-PEG-C2min synthesis was confirmed by NMR. Cell uptake experiments showed that the cell uptake efficiency of PAMAM-PEG-C2min was concentration dependent. In vitro experiments showed that the PC3 and LNCaP cells transfection efficiency and targeting of PAMAM-PEG modified with C2min were significantly improved compared with the PEG modified PAMAM. Conclusion PAMAM-PEG-C2min is a potential targeted drug delivery vehicle. It provides a new technology platform for comprehensive and specific targeting treatment of prostate cancer.
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We sought to investigate the underlying mechanism of action of the long noncoding RNA (lncRNA) LOC283070 in the development of androgen independence in prostate cancer. The interactions between LOC283070 and target proteins were investigated by RNA pull-down and RNA-binding protein immunoprecipitation (RIP) assays. Subcellular fractionation and quantitative reverse transcription-polymerase chain reaction (qRT-PCR) were used to detect the subcellular localization of LOC283070. Western blotting was performed to detect the expression of prohibitin 2 (PHB2). Luciferase activity assays were performed to evaluate the effects of LOC283070 and PHB2 on the androgen receptor (AR) signaling pathway. A methyl thiazolyl tetrazolium (MTT) assay and a growth curve assay were used to test cell viability. Flow cytometry was performed to analyze cell cycles. A transwell assay was employed to test cell migration. We identified PHB2 as an interaction partner of LOC283070 in the pull-down and RIP experiments. Furthermore, we confirmed that the enrichment of LOC283070 with PHB2 in androgen-independent LNCaP (LNCaP-AI) cells was much greater than that in LNCaP cells. Moreover, the expression of PHB2 was not significantly different between the two cell lines, and the expression of LOC283070 in the nuclei of the LNCaP-AI cells was significantly greater than that in the LNCaP cells. In vitro data revealed that PHB2 overexpression significantly inhibited AR activity and cell proliferation and migration and induced accumulation of prostate cancer cells in G0/G1 phase. Moreover, the overexpression of LOC283070 fully abrogated the effects of PHB2 overexpression. In conclusion, we found that LOC283070 can bind to PHB2 located in the nucleus and inhibit its effect, and this is one of the mechanisms by which LOC283070 is involved in the transition of LNCaP cells into androgen-independent cells.
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Objective: To identify mutually regulated proteins in PC-3 and DU145 androgen-independent prostate cancer cell lines treated with 1,5-bis(2-hydroxyphenyl)-1,4-pentadiene-3-one (MS17), and to study the molecular pathways that contributed to the anticancer activity of MS17. Methods: PC-3 and DU145 cells were treated with 3 × EC50 (15 μM) concentration of MS17 for 24 h and were subjected to protein expression profiling using two-dimensional gel electrophoresis and protein identification by mass spectrometry. Selected differentially expressed proteins with significant P-value of P<0.05 and fold change over 1.5-folds were filtered through and ontologically classified. Mutually regulated proteins were ranked by fold change and identified as common protein targets of MS17. Results: Profiling data revealed that, the mutually down-regulated proteins included ACTB and ACTG associated with structural molecule activity, ACTN1 with cell cycle, ACTN4 with cell migration, HNRPK with apoptosis, PLST with morphogenesis and TERA with proteolysis. However, the expressions of CH60 and HS71A respectively associated with response to unfolded protein demonstrated opposing regulation in PC-3 and DU145 cells. Pathway analysis of the differentially expressed proteins in PC-3 cells demonstrated the modulation of top pathways associated with cell-cell adhesion and cytoskeletal organization while in DU145 cells the pathways were associated with proteosomal degradation, regulation of electrolytes and water, regulation control of germ cells and organization of filament assembly/disassembly. Conclusions: The findings of the present study provide an understanding on the anti-tumorigenic activity of MS17 at the proteome level and warrant further research for its potential application for the management and treatment of androgen-independent prostate cancer.
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Objective: To identify mutually regulated proteins in PC-3 and DU145 androgen-independent prostate cancer cell lines treated with 1,5-bis(2-hydroxyphenyl)-1,4-pentadiene-3-one (MS17), and to study the molecular pathways that contributed to the anticancer activity of MS17. Methods: PC-3 and DU145 cells were treated with 3 × EC
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<p><b>Objective</b>To explore the expression of pituitary tumor transforming gene 1 (PTTG1) during the transformation of prostate cancer from androgen-dependent (ADPC) to androgen-independent (AIPC).</p><p><b>METHODS</b>We established an AIPC cell model LNCaP-AI by culturing the androgen-dependent LNCaP cell line in the hormone-deprived medium for over 3 months. The cell model was verified and the PTTG1 expression in the LNCaP cells was detected by Western blot and RT-PCR during hormone deprivation.</p><p><b>RESULTS</b>The AIPC cell model LNCaP-AI was successfully established. The PTTG1 expression was gradually increased in the LNCaP cells with the prolonged time of hormone deprivation and the expressions of matrix metalloproteinases MMP-2 and -9 were elevated at the same time.</p><p><b>CONCLUSIONS</b>The expression of PTTG1 is increased gradually in AIPC, which may be a target of gene therapy for advanced prostate cancer.</p>
Subject(s)
Humans , Male , Blotting, Western , Cell Line, Tumor , Gene Expression Regulation, Neoplastic , Matrix Metalloproteinase 2 , Metabolism , Matrix Metalloproteinase 9 , Metabolism , Neoplasms, Hormone-Dependent , Prostatic Neoplasms , Genetics , Securin , GeneticsABSTRACT
Objective To compare profiles of microRNA between the LNCaP and LNCaP-AI cell lines, so as to futher elucidate the post-transcritional mechanism regulating the progression to androgen-independence. Methods The microRNA profiles of LNCaP and LNCaP-AI cell lines were examined by Agilent's microassay. The expression of six microRNAs was verified by RT-PCR. The functions of differentially expressed microRNAs were eludicated by a search with miRBase software (http://www.mirbase.org/). Results The Aglint's microRNA microassay showed that 11 microRNAs were up-regulated and 27 were down-regulated during the LNCaP progression to androgen-independence. RT-PCR results were consistent with those of the Agilent's microassay chips. By searching the targets of microRNAs in the miRBase software, we found that the differentically expressed microRNAs were mainly involved in regulation of matrix metalloproteinase 9 (MMP-9), Bcl-2, and epithelial growth factor receptor (EGFR) and genes mediating androgen metabolism. Conclusion There is alteration of microRNA during the progression of LNCaP to androgen-independence, which may involve androgen receptor related pathway, metalloenzyme, anti-apoptotic gene and genes related to androgen metabolism.
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The anti-tumor activity of curcumin against androgen-independent prostate cancer cells in vitro and the possible mechanism were investigated.After curcumin treatment,the effect of curcumin on the proliferation of prostate cancer PC-3 cells was assessed by CFSE staining.Flow cytometery (FCM) was performed to analyze the cell cycle and the induction of apoptosis of tumor cells.A luciferase reporter gene assay was used to determine the effects of curcumin on the activities of intracellular NF-κB and AP-1 signaling pathways.The results showed curcumin could effectively inhibit the proliferation of PC-3 cells in vitro (P＜0.05).Cells were arrested at G2/M phase.After curcumin treatment,the percentage of apoptotic cells was significantly higher than in control group (P＜0.05).The resuits of the luciferase assay revealed that curcumin selectively inhibited the activities of the NF-κB and AP-1 signaling pathways in PC-3 cells significantly.It was suggested that curcumin could exert anti-tumor activity against androgen-independent prostate cancer cells in vitro by inhibiting cellular proliferation and inducing apoptosis,which was probably contributed to the inhibition of transcription factors NF-κB and AP- 1.
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Objective: To establish an androgen-independent human prostate cancer cell line model LNCaP-AI. Methods: LNCaP cells were cultured in absence of hormone for a long-term to establish LNCaP cell line LNCaP-AI, which can live without hormone. MTT, immunofluorescence and RT-PCR techniques were used to study the proliferation activity of LNCaP-AI cells and expression and secretion level of PSA by LNCaP-AI cells in absence of hormone. Results: After cultured for 3 months, LNCaP cells gradually became accustomed to the non-hormone condition, showing the characteristics of androgen-independent LNCaP-AI cell line. LNCaP-AI cells rapidly proliferated under the non-hormone condition and secreted PSA. However, PSA mRNA expression level in LNCaP-AI cells was 44% that of the LNCaP cells under hormone condition. Conclusion: Androgen-independent LNCaP-AI cell line may simulate the development of androgen-independence in prostate cancer cells and is an ideal model of androgen-independent prostate cancer cell line.
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Objective: To establish and identify androgen-independent human prostate cancer cell line LNCap by culturing LNCaP cells with gradual deprivation of hormone. Methods: LNCaP cells were cultured in the medium with gradual deprivation of hormone (treated by active carbon to simulate androgen deprivation) for 10 days; and then the cells were cultured with complete deprivation of androgen for 3 months till the cell entered the rapid proliferation phase again. The cell growth and expression of PSA and androgen were examined by CCK-8, immunfluorescence and RT-PCR methods. Results: LNCaP cells grew slowly after deprivation of hormone and took on a neuroendocrine phenotype and cluster growth pattern. After 3 months' non-androgen culture,the cells regained original morphology and growth. CCK-8 indicated that LNCaP cells could grow in non-androgen condition; immunofluorescence assay indicated that LNCaP-AI cells could regain PSA-secreting activity in non-androgen condition; and RT-PCR suggested that androgen was highly expressed in LNCaP-AI cells. Conclusion: Androgen-independent LNCaP cell line can be established by culturing with gradual deprivation of hormone for 3 months.
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We critically evaluated the etiologic role of inorganic arsenic in human prostate cancer. We assessed data from relevant epidemiologic studies concerning environmental inorganic arsenic exposure. Whole animal studies were evaluated as were in vitro model systems of inorganic arsenic carcinogenesis in the prostate. Multiple studies in humans reveal an association between environmental inorganic arsenic exposure and prostate cancer mortality or incidence. Many of these human studies provide clear evidence of a dose-response relationship. Relevant whole animal models showing a relationship between inorganic arsenic and prostate cancer are not available. However, cellular model systems indicate arsenic can induce malignant transformation of human prostate epithelial cells in vitro. Arsenic also appears to impact prostate cancer cell progression by precipitating events leading to androgen independence in vitro. Available evidence in human populations and human cells in vitro indicates that the prostate is a target for inorganic arsenic carcinogenesis. A role for this common environmental contaminant in human prostate cancer initiation and/or progression would be very important.
Realizamos uma avaliação crítica do papel etiológico do arsênico inorgânico no câncer de próstata humano. Avaliamos dados de estudos epidemiológicos relevantes referentes à exposição ao arsênico inorgânico ambiental. Foram avaliados estudos com animais completos, bem como sistemas de modelo in vitro de carcinogênese decorrente de arsênico inorgânico na próstata. Estudos múltiplos em seres humanos revelaram uma associação entre exposição ao arsênico inorgânico ambiental e mortalidade por ou incidência de câncer de próstata. Muitos desses estudos em seres humanos oferecem indícios claros de uma relação dose-resposta. Não se encontram disponíveis modelos animais completos relevantes que mostrem uma relação entre arsênico inorgânico e câncer de próstata. Contudo, os sistemas de modelos celulares indicam que o arsênico é capaz de levar a transformações malignas de células epiteliais da próstata humana in vitro. Aparentemente, o arsênico também tem um impacto na progressão do câncer de próstata ao precipitar eventos que levam à independência de andrógeno in vitro. Os indícios disponíveis em populações humanas e células humanas in vitro indicam que a próstata é alvo da carcinogênese de arsênico inorgânico. Um papel para esse contaminante ambiental comum na iniciação e/ou progressão do câncer de próstata humano seria de suma importância.
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Objective To construct the prostatic specific promoter used to induce the gene therapy aiming at androgen independent prostatic carcinoma and evaluate the activity. Methods Through two steps of polymerase chain reaction (PCR), androgen response elements (AREs) in rPB were replaced by synthetic retinoic acid response elements (RAREs). Then the modified rPBs were connected with the plasmid. The activity was evaluated. Results Constructions were confirmed to be successful by electrophoresis and gene sequencing. Conclusion Modified rPB should be the prostatic specific promoter which can induce the gene therapy aiming at androgen-independent prostatic carcinoma controlled by retinoic acid. After being constructed, the modified rPBs were used to confirm our ideas about the experiment design and the capability inducing the gene expression of different modified rPBs was compared.
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PURPOSE: Three-dimensional(3-D) organization is critical for both the normal development and, tumor growth and progression. Cell-cell and cell-matrix interactions determine normal prostate development and its subsequent neoplastic transformation. To understand the epigenetic factors that lead to cell transformation, a 3-D human prostate cell culture was established with prostate epithelial cells grown in a rotating-wall vessel(RWV) under microgravity-simulated conditions with either alone or with prostate or bone stromal cells. We tested the hypothesis of whether phenotypic and genotypic alterations of LNCaP cells may be achived when grown as 3-D organoids. MATERIALS AND METHODS: LNCaP cells were seeded in RWV alone and with either human prostate or bone fibroblasts. After period of 2 months, RWV1, 2, and 3 cell lines were established from the prostate organoids and were characterized. RESULTS: While LNCaP cells injected orthotopically failed to form tumors in castrated mouse, RWV-derived cell lines formed PSA-producing tumors and metastasized to lymph node, bone, lung and liver, which stained positively by PSA antibody. RWV cells grew faster than parental LNCaP, especially in sex hormone-free conditions. Unlike parental LNCaP cells which respond positively to androgen and estrogen-induced growth and PSA expression, RWV cells are insensitive to sex steroid-induced growth, but remain sensitive to androgen for induction of PSA expression. Comparative genomic hybridization(CGH) results demonstrated that RWV cell lines have different chromosomal gain and loss each other as compared to those of LNCaP. CONCLUSIONS: Cell-cell and cell-matrix interactions of androgen-dependent and non-metastatic LNCaP cultured alone or with either prostate or bone fibroblasts in 3-D culture under microgravity-simulated conditions resulted in induction of androgen- independent and metastatic LNCaP sublines, RWV cell lines, meaning androgen- independent progression. Phenotype and genotype of RWV cell lines are definitely dissimilar to those of parental LNCaP. 3-D culture of prostatic epithelial cells under microgravity-simulated conditions could be novel approach to the study of normal development and cancer of prostate as an ideal in vitro model and, will be further exploited.
Subject(s)
Animals , Humans , Mice , Cell Culture Techniques , Cell Line , Epigenomics , Epithelial Cells , Fibroblasts , Genotype , Liver , Lung , Lymph Nodes , Organoids , Parents , Phenotype , Prostate , Prostatic Neoplasms , Stromal CellsABSTRACT
PURPOSE: A cell-cell interaction in which in vivo inoculation of androgen-dependent, non-tumorigenic LNCaP and human bone fibroblast resulted in derivation of androgen-independent and metastatic LNCaP subline(C4-2) in castrated hosts. The purpose of this study is to evaluate if human prostate fibroblasts when grown together with LNCaP may promote androgen-independent growth and enhance metastatic potential. MATERIALS AND METHODS: LNCaP cells and human prostate fibroblasts derived either from peripheral or transition zone co-inoculated in athymic mice for 8 weeks, and then mice were castrated. The chimeric tumors were maintained for additional 4 weeks. The LNCaP sublines, designated P4 and T4, were established and characterized. These sublines were co-inoculated again in castrated mice with human prostate fibroblasts for 8-12 weeks. And then second generation LNCaP sublines, P4-2 and T4-2, were established and also characterized. RESULTS: Marked cytogenetic alterations were observed in P4-2, P4, T4-2 and T4 LNCaP sublines in comparison to parental LNCaP. Although LNCaP cells injected orthotopically did not form tumors in castrated hosts, LNCaP sublines formed PSA-producing tumors and had metastatic potentials to lymph node, lung, liver and bone. These P and T sublines had androgen-independent growth characteristics and metastatic potential. CONCLUSIONS: Cell-cell interactions between prostatic epithelium and their surrounding fibroblasts could contribute to androgen-independent characteristics and enhanced metastatic potential of localized prostate cancer in vivo.