Project description:High levels of GLI (GLI1 and GLI2) mRNA and GLI luciferase reporter activity were detected in the androgen independent prostate cancer cell lines DU145 and PC-3 compared to the androgen-dependent LNCaP prostate cancer cell line. Subsequently, we observed that ectopic GLI1 promoted hormone independence in LNCaP cells (LNCaP-GLI1). We compared the gene expression profile of LNCaP-pBP (empty vector), LNCaP-GLI1, DU145, and PC-3 cells globally as well as to identify GLI1-regulated genes that may contribute to hormone independence. RNA was harvested and analysed from LNCap-pBP (control/reference sample), LNCaP-GLI1, DU145 and PC-3 cells
Project description:High levels of GLI (GLI1 and GLI2) mRNA and GLI luciferase reporter activity were detected in the androgen independent prostate cancer cell lines DU145 and PC-3 compared to the androgen-dependent LNCaP prostate cancer cell line. Subsequently, we observed that ectopic GLI1 promoted hormone independence in LNCaP cells (LNCaP-GLI1). We compared the gene expression profile of LNCaP-pBP (empty vector), LNCaP-GLI1, DU145, and PC-3 cells globally as well as to identify GLI1-regulated genes that may contribute to hormone independence.
Project description:Despite significant progress in therapy, melanoma is still the most lethal form of skin cancer, with a rising incidence worldwide. Little is known about the impact of deregulated Hedgehog-GLI (HH-GLI) signalling pathway in the progression of this disease. Based on previous research, we hypothesized that in melanoma activation of HH-GLI signaling pathway is non- canonical due to its crosstalk with MAPK signaling pathway, which is the most deregulated pathway in melanoma. In order to investigate the link between the two pathways and to find novel GLI transcriptional targets that could be considered for potential combination therapy, we performed RNA sequencing on three melanoma cell lines with overexpressed GLI1, GLI2 and GLI3 and combined them with results of ChIP sequencing on endogenous GLI1, GLI2 and GLI3 proteins on the same cell lines. RNA-seq revealed a total of 808 DEGs for GLI1, 941 DEGs for GLI2 and 58 DEGs for GLI3. ChIP-seq identified 527 genes that contained GLI1 binding sites in their promoters, 1103 for GLI2 and 553 for GLI3. After combining these results, 21 targets were selected for validation by qPCR. Fifteen of these targets were validated in the tested cell lines, 6 of which were detected by both RNA-seq and ChIP-seq.
Project description:The androgen receptor (AR) plays a key role in progression to incurable androgen-ablation resistant prostate cancer (PCA). We have identified three novel AR splice variants lacking the ligand binding domain (designated as AR3, AR4 and AR5) in hormone insensitive PCA cells. AR3, one of the major splice variants expressed in human prostate tissues, is constitutively active and its transcriptional activity is not regulated by androgens or antiandrogens. Immunohistochemistry analysis on tissue microarrays containing 429 human prostate tissue samples shows that AR3 is significantly upregulated during PCA progression and AR3 expression level is correlated with the risk of tumor recurrence after radical prostatectomy. Overexpression of AR3 confers ablation-independent growth of PCA cells while specific knock-down of AR3 expression (without altering AR level) in hormone resistant PCA cells attenuates their growth under androgen-depleted conditions in both cell culture and xenograft models, suggesting an indispensable role of AR3 in ablation-independent growth of PCA cells. Furthermore, AR3 may play a distinct yet essential role in ablation-independent growth through regulating a unique set of genes including AKT1, which are not regulated by the prototype AR. Our data suggest that aberrant expression of AR splice variants may be a novel mechanism underlying ablation-independence during PCA progression and AR3 may serve as a prognostic marker to predict patient outcome in response to hormonal therapy. Given that these novel AR splice variants are not inhibited by currently available anti-androgen drugs, development of new drugs targeting these AR isoforms may potentially be effective for treatment of ablation-resistant PCA. Total RNA was extracted from CWR-R1 and 22Rv1 cells treated with shAR3-1, shARa and the scrambled shRNA control, respectively. Each of CWR-R1 and 22Rv1 cells treated with shAR3-1 was compared with the scrambled shRNA control. The same experiments were performed for the cells treated with shARa.
Project description:The androgen receptor (AR) plays a key role in progression to incurable androgen-ablation resistant prostate cancer (PCA). We have identified three novel AR splice variants lacking the ligand binding domain (designated as AR3, AR4 and AR5) in hormone insensitive PCA cells. AR3, one of the major splice variants expressed in human prostate tissues, is constitutively active and its transcriptional activity is not regulated by androgens or antiandrogens. Immunohistochemistry analysis on tissue microarrays containing 429 human prostate tissue samples shows that AR3 is significantly upregulated during PCA progression and AR3 expression level is correlated with the risk of tumor recurrence after radical prostatectomy. Overexpression of AR3 confers ablation-independent growth of PCA cells while specific knock-down of AR3 expression (without altering AR level) in hormone resistant PCA cells attenuates their growth under androgen-depleted conditions in both cell culture and xenograft models, suggesting an indispensable role of AR3 in ablation-independent growth of PCA cells. Furthermore, AR3 may play a distinct yet essential role in ablation-independent growth through regulating a unique set of genes including AKT1, which are not regulated by the prototype AR. Our data suggest that aberrant expression of AR splice variants may be a novel mechanism underlying ablation-independence during PCA progression and AR3 may serve as a prognostic marker to predict patient outcome in response to hormonal therapy. Given that these novel AR splice variants are not inhibited by currently available anti-androgen drugs, development of new drugs targeting these AR isoforms may potentially be effective for treatment of ablation-resistant PCA.
Project description:The Androgen Receptor (AR) is the master regulator of Prostate Cancer (PCa) development, and inhibition of AR signalling is the most effective PCa treatment. AR is expressed in PCa cells and also in the PCa-associated stroma, including infiltrating macrophages ). Macrophages play a decisive role in PCa initiation and progression, however, the role of AR in these cells remains largely unexplored. Here we show that AR signalling in macrophage-like THP-1 cell line supports PCa cell line migration and invasion in culture via increased Triggering REceptor of Macrophage-1 (TREM-1) signalling and expression of its downstream cytokines.
Project description:Loss of olfactomedin 4 (OLFM4) gene expression is associated with the progression of human prostate cancer, but its role and the molecular mechanisms involved in this process have not been completely understood. In this study, we found that Olfm4-knockout mice developed prostatic intraepithelial neoplasia and prostatic adenocarcinoma. Importantly, we found that the hedgehog-signaling pathway was significantly upregulated in the Olfm4-knockout mouse model. We also found that restoration of OLFM4 in human prostate-cancer cells that lack OLFM4 expression significantly downregulated hedgehog signaling-pathway component expression. Furthermore, we demonstrated that the OLFM4 protein interacts with sonic hedgehog protein, as well as significantly inhibits GLI-reporter activity. Bioinformatic and immunohistochemistry analyses revealed that decreased OLFM4 and increased SHH expression was significantly associated with advanced human prostate cancer. Thus, olfactomedin 4 appears to play a critical role in regulating progression of prostate cancer, and has potential as a new biomarker for prostate cancer.
Project description:Prostate cancer (PCa) is the most common malignant carcinoma that develops in men in Western countries. Up to 30% of patients continue to suffer from disease progression following radical prostatectomy. Therefore, better prognostic markers and molecular targets for cancer treatment are needed. MicroRNA (miRNA) has the potential to be used as biomarkers and as a therapeutic target for the treatment of various cancers, including PCa. Here, to determine how miRNA is involved in PCa progression, we investigated the miRNA expression profiles of 3 PCa cell lines, namely PC3, DU145, and LNCaP, and 2 normal prostate cell lines, namely RWPE-1 and PrSc, using miRNA microarrays. We investigated miRNA genes that were significantly upregulated in PCa cell lines (PC3, DU145, LNCaP) compared with normal cell lines (RWPE-1, PrSc).
Project description:Deregulation of cytokine- and growth factor signaling due to altered expression of endogenous regulators is well recognized in prostate and other cancers. Suppressor of cytokine signaling 2 (SOCS2) is a key regulator of growth hormone, IGF and prolactin signaling, that have been implicated in carcinogenesis. In this study we elucidate expression pattern and functional significance of SOCS2 in prostate cancer (PCa). Protein expression analysis employing tissue microarrays from two independent patient cohorts revealed significantly enhanced expression in tumor compared to benign tissue as well as association with Gleason score and disease progression. In vitro and in vivo assays uncovered the involvement of SOCS2 in the regulation of cell growth and apoptosis. Functionally, SOCS2 knockdown inhibited prostate cancer cell proliferation and xenograft growth in a CAM assay. Decreased cell growth after SOCS2 downregulation was associated with cell-cycle arrest and apoptosis. In addition, we prove for the first time that SOCS2 expression is significantly elevated upon androgenic stimulation in androgen receptor-positive cell lines, providing a possible mechanistic explanation for high SOCS2 levels in PCa tissue. Consequently, SOCS2 expression correlated with androgen receptor expression in malignant tissue of patients. Taken together, our study linked increased SOCS2 expression in PCa with a pro-proliferative role in vitro and in vivo. Prostate cancer cell lines LNCaP, DUCaP and VCaP cells were cultured in the absence or presence of R1881, an androgen in three independent experiments. Differential gene expression was determined by comparing R1881 treated samples with the corresponding controls (EtOH treated samples).
Project description:Attenuation of Hedgehog (Hh) pathway activity leads to increased prostate branching during adult prostate regeneration. In order to identify genes regulated by the Hh pathway that might be involved in adult prostate branching, we performed transcriptional profiling of regenerating prostates from wild-type or Gli1-/- mutant mice, which have attenuated Hh pathway activity. 6 total samples were analyzed. 3 wild-type prostates and 3 Gli-/- mutant prostates were analyzed.