Project description:To decipher the contribution of STAT3, IRF1 and PGAM5 to androgen-responsive gene expression, effect of siRNA-mediated silencing of STAT3, IRF1 and PGAM5 on expression of androgen-dependent genes was studied.
Project description:The ligand-activated androgen receptor is a transcription factor that drives prostate cancer growth. Blocking androgen-activation of androgen receptor via androgen deprivation therapy is the default treatment for metastatic prostate cancer. Despite initial remissions, androgen deprivation invariably fails and prostate cancer progresses to castration-recurrent disease, which still relies on aberrantly activated androgen receptor. Alternative approaches are needed to inhibit androgen receptor action in prostate cancer that has failed androgen deprivation therapy. Our laboratory has been exploring the therapeutic potential of a non-canonical androgen receptor signaling mechanism wherein androgen receptor stimulates another transcription factor, Serum Response Factor. Serum Response Factor-mediated androgen receptor action correlates with prostate cancer progression and is enriched in castration-recurrent prostate cancer. Inhibiting Serum Response Factor-dependent androgen receptor action may be an effective treatment strategy following failure of androgen deprivation therapy but remains poorly understood. We have recently isolated UPF1 and RCOR1 as putative novel mediators of Serum Response Factor-dependent androgen receptor action. Here, we perform RNA-Seq assays to determine the contribution of UPF1 and RCOR1 to the androgen response of prostate cancer cells.
Project description:To investigate the mechanisms of drug resistance and castration resistance in prostate cancer, we performed proteomic sequencing on androgen-dependent prostate cancer cells (LNCaP) and androgen-independent cells (AI) treated with enzalutamide.
Project description:Galiellalactone (GL) is a fungal metabolite that presents antitumor and anti-inflammatory activities in vitro and in vivo. Previous studies have shown that GL targets NF-KB and STAT3 pathways and induces G2/M cell cycle arrest in androgen-insensitive prostate cancer cells. In this study, we show that GL-induced cell cycle arrest is independent of the NF-KB and STAT3 pathways in DU145 and PC-3 cells, and also that GL did not affect cell cycling in androgen-sensitive prostate cancer cell such as LNCaP and 22Rv1 cells. In addition, we showed confluence resistance to GL in DU145 cells. Using a SWATH proteomic approach we identified the down-regulation of Nucleolar and spindle associated protein 1 (NUSAP1) under DU145 confluence and in LNCaP cells. Also, the inhibition of NUSAP1 by siRNAs induced resistance to GL in DU145 cells, suggesting that NUSAP1 may be a target for GL and could be useful as biomarker for responsiveness of the antitumor activity of GL.
Project description:Prostate cancer is the second most occurring cancer in men worldwide, and with the advances made with screening for prostate-specific antigen, it has been prone to early diagnosis and over-treatment. To better understand the mechanisms of tumorigenesis and possible treatment responses, we developed a mathematical model of prostate cancer which considers the major signalling pathways known to be deregulated. The model includes pathways such as androgen receptor, MAPK, Wnt, NFkB, PI3K/AKT, MAPK, mTOR, SHH, the cell cycle, the epithelial-mesenchymal transition (EMT), apoptosis and DNA damage pathways. The final model accounts for 133 nodes and 449 edges. We applied a methodology to personalise this Boolean model to molecular data to reflect the heterogeneity and specific response to perturbations of cancer patients, using TCGA and GDSC datasets.
Project description:Following androgen ablation therapy (AAT), the vast majority of prostate cancer patients develop treatment resistance with a median time of 18-24 months to disease progression. To identify molecular targets that aid in prostate cancer cell survival and contribute to the androgen independent phenotype, we evaluated changes in LNCaP cell gene expression during 12 months of androgen deprivation. At time points reflecting critical growth and phenotypic changes, we performed Affymetrix expression array analysis to examine the effects of androgen deprivation during the acute response, during the period of apparent quiescence, and during the emergence of highly proliferative, androgen-independent prostate cancer cells (LNCaP-AI). We discovered alterations in gene expression for a host of molecules associated with promoting prostate cancer cell growth and survival, regulating cell cycle progression, apoptosis and adrenal androgen metabolism, in addition to AR co-regulators and markers of neuroendocrine disease. These findings illustrate the complexity and unpredictable nature of cancer cell biology and contribute greatly to our understanding of how prostate cancer cells likely survive AAT. The value of this longitudinal approach lies in the ability to examine gene expression changes throughout the cellular response to androgen deprivation; it provides a more dynamic illustration of those genes which contribute to disease progression in addition to specific genes which constitute a malignant androgen-independent phenotype. In conclusion, it is of great importance that we employ new approaches, such as the one proposed here, to continue exploring the cellular mechanisms of therapy resistance and identify promising targets to improve cancer therapeutics. Experiment Overall Design: To identify molecular targets that aid in prostate cancer cell survival and contribute to the androgen independent phenotype, we evaluated changes in LNCaP cell gene expression during 12 months of androgen deprivation. At time points reflecting critical growth and phenotypic changes, we performed Affymetrix expression array analysis to examine the effects of androgen deprivation during the acute response, during the period of apparent quiescence, and during the emergence of highly proliferative, androgen-independent prostate cancer cells (LNCaP-AI).
Project description:Aberrant androgen receptor (AR)-mediated transcription is a critical driver in progression of human prostate cancer. It's known that different doses of androgens can elicit differential transcriptional and proliferative responses in prostate-tumor cells. Here, we set out to examine the androgenic regulation of glycoprotein expression in the membrane fraction of prostate-tumor cells that could serve as mediators or markers of androgen-induced proliferative responses observed in prostate-tumor cells. A bioanalytical workflow involving lectin-affinity chromatography and label-free quantitative mass spectrometry was used to identify androgen-sensitive glycomembrane protein expression associated with androgen-mediated proliferation. This study would facilitate the identification of surface membrane proteins involved in androgen-mediated proliferation and provide potential therapeutic targets in the detection treatment of proliferation prostate-tumors.
Project description:To decipher the contribution of WDR77 and p53 to androgen-responsive gene expression, effect of siRNA-mediated silencing of WDR77 and p53 on expression of androgen-dependent genes was studied. Human LNCaP prostate cancer cells were transfected with individual siRNA SmartPools targeting WDR77 or p53 or a non-targeting siRNA SmartPool. Forty-two hours after transfection, cells were treated with synthetic androgen R1881 (5nM) or vehicle. Three biological replicates were generated per treatment group. Forty-eight hours later, total RNA was isolated and processed for Illumina oligoarray analysis.