4f6b4c86-e174-4cdd-a2ff-9a66ebe51a77 - samples
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PROVIDER: EGAD00001007685 | EGA |
REPOSITORIES: EGA
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Project description:Background. Androgen receptor splice variant-7 (AR-V7) is a truncated form of the androgen receptor protein which lacks the ligand-binding domain, the target of enzalutamide and abiraterone, but remains constitutively active as a transcription factor. We hypothesized that detection of AR-V7 in circulating tumor cells (CTCs) from men with advanced prostate cancer would be associated with resistance to enzalutamide and abiraterone. Methods. We used quantitative reverse-transcription polymerase-chain-reaction (qRT-PCR) to interrogate CTCs for the presence or absence of AR-V7 from prospectively enrolled patients with metastatic castration-resistant prostate cancer initiating treatment with either enzalutamide or abiraterone. We examined associations between AR-V7 status and PSA response rates, PSA-progression-free-survival (PSA-PFS), clinical/radiographic-progression-free-survival (PFS), and overall survival (OS). Multivariable Cox regression analyses were performed to determine the independent effect of AR-V7 status on clinical outcomes. Results. Thirty-one enzalutamide-treated patients and thirty-one abiraterone-treated patients were enrolled, of which 38.7% and 19.4% had detectable AR-V7 from CTCs, respectively. Among men receiving enzalutamide, AR-V7–positive patients had inferior PSA response rates (0% vs 52.6%, P=0.004), PSA-PFS (median: 1.4 vs 6.0 months, P<0.001), PFS (median: 2.1 vs 6.1 months, P<0.001), and OS (median: 5.5 months vs not reached, P=0.002) compared to AR-V7–negative patients. Similarly, among men receiving abiraterone, AR-V7–positive patients had inferior PSA response rates (0% vs 68.0%, P=0.004), PSA-PFS (median: 1.3 months vs not reached, P<0.001), PFS (median: 2.3 months vs not reached, P<0.001), and OS (median: 10.6 months vs not reached, P=0.006). The negative prognostic impact of AR-V7 was maintained after adjusting for full-length-AR expression. Conclusions. Detection of AR-V7 in CTCs from patients with castration-resistant prostate cancer is associated with resistance to enzalutamide and abiraterone. A total of four metastatic castration-resistant prostate tumor samples from four patients were subjected to RNA-seq. Two samples were positive for androgen receptor splice variant 7 and the other two were negative for this variant.
2014-09-03 | E-GEOD-56701 | biostudies-arrayexpress
Project description:Tiragolumab, an anti-TIGIT antibody with an active IgG1κ Fc, demonstrated improved outcomes in the phase 2 CITYSCAPE trial (ClinicalTrials.gov: NCT03563716) when combined with atezolizumab (anti-PD-L1) versus atezolizumab alone. However, there remains little consensus on the mechanism(s) of response with this combination. Here we find that a high baseline of intratumoural macrophages and regulatory T cells is associated with better outcomes in patients treated with atezolizumab plus tiragolumab but not with atezolizumab alone. Serum sample analysis revealed that macrophage activation is associated with a clinical benefit in patients who received the combination treatment. In mouse tumour models, tiragolumab surrogate antibodies inflamed tumour-associated macrophages, monocytes and dendritic cells through Fcγ receptors (FcγR), in turn driving anti-tumour CD8+ T cells from an exhausted effector-like state to a more memory-like state. These results reveal a mechanism of action through which TIGIT checkpoint inhibitors can remodel immunosuppressive tumour microenvironments, and suggest that FcγR engagement is an important consideration in anti-TIGIT antibody development.
2024-03-04 | GSE260816 | GEO
Project description:Enzalutamide (formerly MDV3100 and available commercially as Xtandi), a novel androgen receptor (AR) signaling inhibitor, blocks the growth of castration-resistant prostate cancer (CRPC) in cellular model systems and was shown in a clinical study to increase survival in patients with metastatic CRPC. Enzalutamide inhibits multiple steps of AR signaling: (1) binding of androgens to AR, (2) AR nuclear translocation, and (3) association of AR with DNA. Here we used Affymetrix human genome microarray technology to investigate the global programme of gene expression of LNCaP cells in response to enzalutamide alone and in the context of DHT-stimulated androgen receptor gene expression. LNCaP cells were grown in RPMI 1640 supplemented with 5% hormone depleted FBS and treated with vehicle (control sample) , DHT (100 nM), enzalutamide (1 or 10 M-BM-5M) or DHT (100 nM) plus enzalutamide (1 or 10 M-BM-5M)for 16 hours for RNA extraction and hybridization. Each condition was done in triplicate.
2013-04-01 | E-GEOD-44905 | biostudies-arrayexpress
Project description:Background. Androgen receptor splice variant-7 (AR-V7) is a truncated form of the androgen receptor protein which lacks the ligand-binding domain, the target of enzalutamide and abiraterone, but remains constitutively active as a transcription factor. We hypothesized that detection of AR-V7 in circulating tumor cells (CTCs) from men with advanced prostate cancer would be associated with resistance to enzalutamide and abiraterone. Methods. We used quantitative reverse-transcription polymerase-chain-reaction (qRT-PCR) to interrogate CTCs for the presence or absence of AR-V7 from prospectively enrolled patients with metastatic castration-resistant prostate cancer initiating treatment with either enzalutamide or abiraterone. We examined associations between AR-V7 status and PSA response rates, PSA-progression-free-survival (PSA-PFS), clinical/radiographic-progression-free-survival (PFS), and overall survival (OS). Multivariable Cox regression analyses were performed to determine the independent effect of AR-V7 status on clinical outcomes. Results. Thirty-one enzalutamide-treated patients and thirty-one abiraterone-treated patients were enrolled, of which 38.7% and 19.4% had detectable AR-V7 from CTCs, respectively. Among men receiving enzalutamide, AR-V7–positive patients had inferior PSA response rates (0% vs 52.6%, P=0.004), PSA-PFS (median: 1.4 vs 6.0 months, P<0.001), PFS (median: 2.1 vs 6.1 months, P<0.001), and OS (median: 5.5 months vs not reached, P=0.002) compared to AR-V7–negative patients. Similarly, among men receiving abiraterone, AR-V7–positive patients had inferior PSA response rates (0% vs 68.0%, P=0.004), PSA-PFS (median: 1.3 months vs not reached, P<0.001), PFS (median: 2.3 months vs not reached, P<0.001), and OS (median: 10.6 months vs not reached, P=0.006). The negative prognostic impact of AR-V7 was maintained after adjusting for full-length-AR expression. Conclusions. Detection of AR-V7 in CTCs from patients with castration-resistant prostate cancer is associated with resistance to enzalutamide and abiraterone.
2014-09-03 | GSE56701 | GEO
Project description:Prostate cancer is the most commonly diagnosed and second-most lethal cancer among men in the United States. The vast majority of prostate cancer deaths are due to castration-resistant prostate cancer (CRPC) â?? the lethal form of the disease that has progressed despite therapies that interfere with activation of androgen receptor (AR) signaling. One emergent resistance mechanism to medical castration is synthesis of intratumoral androgens that activate the AR. This insight led to the development of the AR antagonist enzalutamide. However, resistance to enzalutamide invariably develops, and disease progression is nearly universal. One mechanism of resistance to enzalutamide is an F877L mutation in the AR ligand-binding domain that can convert enzalutamide to an agonist of AR activity. However, mechanisms that contribute to the agonist switch had not been fully clarified, and there were no therapies to block AR F877L. Using cell line models of castration-resistant prostate cancer (CRPC), we determined that cellular androgen content influences enzalutamide agonism of mutant F877L AR. Further, enzalutamide treatment of AR F877L-expressing cell lines recapitulated the effects of androgen activation of F877L AR or wild-type AR. Because the BET bromodomain inhibitor JQ-1 was previously shown to block androgen activation of wild-type AR, we tested JQ-1 in AR F877L-expressing CRPC models. We determined that JQ-1 suppressed androgen or enzalutamide activation of mutant F877L AR and suppressed growth of mutant F877L AR CRPC tumors in vivo, demonstrating a new strategy to treat tumors harboring this mutation. RNA-seq profiles of prostate cancer cell lines to understand gene expression associated with enzalutamide treatment
2016-06-10 | E-GEOD-69896 | biostudies-arrayexpress
Project description:Enzalutamide (formerly MDV3100 and available commercially as Xtandi), a novel androgen receptor (AR) signaling inhibitor, blocks the growth of castration-resistant prostate cancer (CRPC) in cellular model systems and was shown in a clinical study to increase survival in patients with metastatic CRPC. Enzalutamide inhibits multiple steps of AR signaling: (1) binding of androgens to AR, (2) AR nuclear translocation, and (3) association of AR with DNA. Here we used Affymetrix human genome microarray technology to investigate the global programme of gene expression of LNCaP cells in response to enzalutamide alone and in the context of DHT-stimulated androgen receptor gene expression.
2013-04-01 | GSE44905 | GEO
Project description:The goal of this study was to determine how androgen receptor inhibition alters transcriptional programs in castration-resistant prostate cancer cells. 16D castration-resistant prostate cancer cells were grown in the presence of 10 micromolar enzalutamide for 24, 48, 96, 144 hours or for more than 2 months (long-term). Analysis shows that androgen receptor target genes are reduced with enzalutamide while metabolic genes are also differentially expressed.
2022-05-12 | GSE202885 | GEO
Project description:In 2012, the US Food and Drug Administration approved enzalutamide (Xtandi) for the treatment of patients with metastatic castration-resistant prostate cancer who have previously received docetaxel. In most patients, enzalutamide halts progression of the disease for a short period of time, but patients usually relapse, which is associated with poor prognosis. Identifying the genes and pathways that the cancer cells use to overcome enzalutamide are of interest, because new interventions aimed at preventing relapse after enzalutamide therapy would have therapeutic value to late-stage prostate cancer patients. In this study, we took advantage of RNA interference techniques and an in vitro model of castration-resistant prostate cancer cells to identify genes that drive resistance to enzalutamide.
2021-01-10 | GSE156816 | GEO
Project description:Background: Most forms of castration-resistant prostate cancer (CRPC) are dependent on the androgen receptor (AR) for survival. While, enzalutamide provides a substantial survival benefit, it is not curative and many patients develop resistance to therapy. Although not yet fully understood, resistance can develop through a number of mechanisms, such as AR copy number gain, the generation of splice variants such as AR-V7 and mutations within the ligand binding domain (LBD) of the AR. Circular RNAs (circRNAs) are a novel type of non-coding RNA, which can regulate the function of miRNA, and may play a key role in the development of drug resistance. CircRNAs are highly resistant to degradation, are detectable in plasma and, therefore may serve a role as clinical biomarkers. Methods: AR-V7 expression was assessed in an isogenic model of enzalutamide resistance. The model consisted of age matched control cells and two sub-lines displaying varied resistance to enzalutamide. circRNA profiling was performed on the panel using a high throughout microarray assay. Bioinformatic analysis identified a number of differentially expressed circRNAs and predicted five miRNA binding sites for each circRNA. miRNAs were stratified based on known associations with prostate cancer, and targets were validated using qPCR. Results: Overall, circRNAs were more often down regulated in resistant cell lines compared with control (588 vs. 278). Of particular interest was hsa_circ_0004870 (Probe ID ASCRP3009662), which was down-regulated in enzalutamide resistant cells (p≤0.05, vs. sensitive cells), decreased in AR positive cells (p≤0.01, vs. AR negative), and in malignant cells (p≤0.01, vs. benign). The associated parental gene was identified as RBM39, a member of the U2AF65 family of proteins. Both genes were down-regulated in resistant cells (p<0.05, vs. sensitive cells). Conclusion: This is one of the first studies to profile and demonstrate discrete circRNA expression patterns in an enzalutamide resistant cell line model of prostate cancer. Our data suggests that hsa_circ_0004870, through RBM39, may play a critical role in the development of enzalutamide resistance in CRPC.
2018-10-31 | GSE118959 | GEO
Project description:The prognosis of patients with metastatic castration-resistant prostate cancer (mCRPC) is variable. Several blood-related prognostic factors have been reported, including transcriptional profiling of whole blood and neutrophil to lymphocyte ratio. We aimed to address the contribution of distinct whole blood immune cell components to the prognosis of these patients. Subjects/Patients and Methods: Pre-treatment whole blood samples from chemotherapy-naïve mCRPC patients were prospectively collected before treatment with enzalutamide. The study consisted of a training cohort including 98 patients treated with enzalutamide in a phase 2 biomarker clinical trial (NCT02288936)
2024-08-02 | GSE248619 | GEO