is both the most frequently altered gene in primary prostate cancer and a critical factor enabling cellular infection by coronaviruses, including SARS-CoV-2. The modulation of its expression by sex ...steroids could contribute to the male predominance of severe infections, and given that
has no known indispensable functions, and inhibitors are available, it is an appealing target for prevention or treatment of respiratory viral infections.
Introduction of novel agents for the management of advanced prostate cancer provides a range of treatment options with notable benefits for men with metastatic castration-resistant prostate cancer ...(mCRPC). At the same time, understanding of optimal patient selection, effective sequential use, and development of resistance patterns remains incomplete.
To review current systemic therapies and recent advances in drug development for mCRPC and strategies to aid in patient selection and optimal sequencing.
A literature review of PubMed/Medline, Cochrane Library, Current Contents Medicine, Web of Science, Clinical Trial.Gov, WHO-ICTRP (January 2004–November 2017), and the proceedings of major international meetings (2015/2016/2017) was performed in November 2017.
In the last few years, several new options for treatment of mCRPC have shown a survival benefit in phase III trials besides docetaxel:abiraterone, enzalutamide, cabazitaxel, radium-223, and sipuleucel-T. Radium-223 and denosumab have increased options in management of bone metastases. Currently, novel agents such as next-generation androgen receptor (AR) axis-targeting treatments, immunotherapeutics, or therapies targeting other oncogenic and genomic pathways, particularly poly(adenosine diphosphate–ribose) polymerase (PARP) inhibitors and PD-1 inhibitors, are under clinical investigation. With increasing treatment options for mCRPC, information on how to personalize management and how to select and sequence existing therapies is beginning to emerge, as are predictive biomarkers (homologous repair mutations, mismatch repair mutations, AR splice variant 7). Finally, early use of active agents in the castration-sensitive state will likely also change the clinical management of the disease when it becomes castrate resistant.
The emergence of new drugs for mCRPC has improved treatment options dramatically. Currently, systemic treatment options for mCRPC include hormonal therapy, chemotherapy, immunotherapy, and radionuclide therapy as well as bone-modifying agents and palliative or supportive measures. Further, new genetically targeted agents (PARP inhibitors and PD-1 inhibitors) are on the horizon for certain subsets of biomarker-selected patients. The best strategies for patient selection and optimal sequential use to achieve the longest cumulative survival improvement and to prevent early resistance remain unclear.
The current literature and proceedings from relevant congresses related to available systemic agents for the treatment of metastatic castration-resistant prostate cancer, including novel genetically targeted therapies, including poly(adenosine diphosphate–ribose) polymerase inhibitors and PD-1 inhibitors, were reviewed. Current therapies and ongoing developments are discussed.
In the last few years, new therapeutics for the treatment of metastatic castration-resistant prostate cancer have increased survival substantially. While promising novel agents are currently under trial, including genetically targeted therapies (poly(adenosine diphosphate–ribose) polymerase inhibitors and PD-1 inhibitors), further clinical and translational research in predictive biomarkers is needed to optimize treatment selection and sequencing strategies for existing drugs.
Since the discovery of cis-platinum, many transition metal complexes have been synthesized and assayed for antineoplastic activity. In recent years, ruthenium-based molecules have emerged as ...promising antitumor and antimetastatic agents with potential uses in platinum-resistant tumors or as alternatives to platinum. Ruthenium compounds theoretically possess unique biochemical features allowing them to accumulate preferentially in neoplastic tissues and to convert to their active state only after entering tumor cells. Intriguingly, some ruthenium agents show significant activity against cancer metastases but have minimal effects on primary tumors. Two ruthenium-based drugs, NAMI-A and KP1019, have reached human clinical testing. This review will highlight the chemical properties, mechanism of action, preclinical data, and early phase clinical results of these two lead ruthenium compounds. Other promising ruthenium agents will also be reviewed with emphasis on the novel ruthenium compound ONCO4417, and DW1/2 that has demonstrated Pim-1 kinase inhibition in preclinical systems. Further development of these and other ruthenium agents may rely on novel approaches including rational combination strategies as well as identification of potential pharmacodynamic biomarkers of drug activity aiding early phase clinical studies.
Immune checkpoint agents have not yet been approved for use in advanced prostate cancer. This commentary summarizes the challenges related to this issue, in light of a recently reported case of a ...patient with DNA mismatch‐repair deficient castration‐resistant prostate cancer who responded to single‐agent pembrolizumab treatment.
The androgen-receptor isoform encoded by splice variant 7 lacks the ligand-binding domain, which is the target of enzalutamide and abiraterone, but remains constitutively active as a transcription ...factor. We hypothesized that detection of androgen-receptor splice variant 7 messenger RNA (AR-V7) in circulating tumor cells from men with advanced prostate cancer would be associated with resistance to enzalutamide and abiraterone.
We used a quantitative reverse-transcriptase-polymerase-chain-reaction assay to evaluate AR-V7 in circulating tumor cells from prospectively enrolled patients with metastatic castration-resistant prostate cancer who were initiating treatment with either enzalutamide or abiraterone. We examined associations between AR-V7 status (positive vs. negative) and prostate-specific antigen (PSA) response rates (the primary end point), freedom from PSA progression (PSA progression-free survival), clinical or radiographic progression-free survival, and overall survival.
A total of 31 enzalutamide-treated patients and 31 abiraterone-treated patients were enrolled, of whom 39% and 19%, respectively, had detectable AR-V7 in circulating tumor cells. Among men receiving enzalutamide, AR-V7-positive patients had lower PSA response rates than AR-V7-negative patients (0% vs. 53%, P=0.004) and shorter PSA progression-free survival (median, 1.4 months vs. 6.0 months; P<0.001), clinical or radiographic progression-free survival (median, 2.1 months vs. 6.1 months; P<0.001), and overall survival (median, 5.5 months vs. not reached; P=0.002). Similarly, among men receiving abiraterone, AR-V7-positive patients had lower PSA response rates than AR-V7-negative patients (0% vs. 68%, P=0.004) and shorter PSA progression-free survival (median, 1.3 months vs. not reached; P<0.001), clinical or radiographic progression-free survival (median, 2.3 months vs. not reached; P<0.001), and overall survival (median, 10.6 months vs. not reached, P=0.006). The association between AR-V7 detection and therapeutic resistance was maintained after adjustment for expression of full-length androgen receptor messenger RNA.
Detection of AR-V7 in circulating tumor cells from patients with castration-resistant prostate cancer may be associated with resistance to enzalutamide and abiraterone. These findings require large-scale prospective validation. (Funded by the Prostate Cancer Foundation and others.).
Androgen receptor splice variant 7 (AR-V7) results in a truncated receptor, which leads to ligand-independent constitutive activation that is not inhibited by anti-androgen therapies, including ...abiraterone or enzalutamide. Given that previous reports suggested that circulating tumor cell (CTC) AR-V7 detection is a poor prognostic indicator for the clinical efficacy of secondary hormone therapies, we conducted a prospective multicenter validation study.
PROPHECY ( ClinicalTrials.gov identifier: NCT02269982) is a multicenter, prospective-blinded study of men with high-risk mCRPC starting abiraterone acetate or enzalutamide treatment. The primary objective was to validate the prognostic significance of baseline CTC AR-V7 on the basis of radiographic or clinical progression free-survival (PFS) by using the Johns Hopkins University modified-AdnaTest CTC AR-V7 mRNA assay and the Epic Sciences CTC nuclear-specific AR-V7 protein assay. Overall survival (OS) and prostate-specific antigen responses were secondary end points.
We enrolled 118 men with mCRPC who were starting abiraterone or enzalutamide treatment. AR-V7 detection by both the Johns Hopkins and Epic AR-V7 assays was independently associated with shorter PFS (hazard ratio, 1.9 95% CI, 1.1 to 3.3;
= .032 and 2.4 95% CI, 1.1 to 5.1;
= .020, respectively) and OS (hazard ratio, 4.2 95% CI, 2.1 to 8.5 and 3.5 95% CI, 1.6 to 8.1, respectively) after adjusting for CTC number and clinical prognostic factors. Men with AR-V7-positive mCRPC had fewer confirmed prostate-specific antigen responses (0% to 11%) or soft tissue responses (0% to 6%). The observed percentage agreement between the two AR-V7 assays was 82%.
Detection of AR-V7 in CTCs by two blood-based assays is independently associated with shorter PFS and OS with abiraterone or enzalutamide, and such men with mCRPC should be offered alternative treatments.
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