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Purpose To determine whether cotargeting poly (ADP-ribose) polymerase-1 plus androgen receptor is superior to androgen receptor inhibition in metastatic castration-resistant prostate cancer (mCRPC) and whether ETS fusions predict response. Patients and Methods Patients underwent metastatic site biopsy and were stratified by ETS status and randomly assigned to abiraterone plus prednisone without (arm A) or with veliparib (arm B). Primary objectives were: confirmed prostate-specific antigen (PSA) response rate (RR) and whether ETS fusions predicted response. Secondary objectives were: safety, measurable disease RR (mRR), progression-free survival (PFS), and molecular biomarker analysis. A total of 148 patients were randomly assigned to detect a 20% PSA RR improvement. Results A total of 148 patients with mCRPC were randomly assigned: arm A, n = 72; arm B, n = 76. There were no differences in PSA RR (63.9% v 72.4%; P = .27), mRR (45.0% v 52.2%; P = .51), or median PFS (10.1 v 11 months; P = .99). ETS fusions did not predict response. Exploratory analysis of tumor sequencing (80 patients) revealed: 41 patients (51%) were ETS positive, 20 (25%) had DNA-damage repair defect (DRD), 41 (51%) had AR amplification or copy gain, 34 (43%) had PTEN mutation, 33 (41%) had TP53 mutation, 39 (49%) had PIK3CA pathway activation, and 12 (15%) had WNT pathway alteration. Patients with DRD had significantly higher PSA RR (90% v 56.7%; P = .007) and mRR (87.5% v 38.6%; P = .001), PSA decline ≥ 90% (75% v 25%; P = .001), and longer median PFS (14.5 v 8.1 months; P = .025) versus those with wild-type tumors. Median PFS was longer in patients with normal PTEN (13.5 v 6.7 months; P = .02), TP53 (13.5 v 7.7 months; P = .01), and PIK3CA (13.8 v 8.3 months; P = .03) versus those with mutation or activation. In multivariable analysis adjusting for clinical covariates, DRD association with PFS remained significant. Conclusion Veliparib and ETS status did not affect response. Exploratory analysis identified a novel DRD association with mCRPC outcomes.

The trend toward precision-based therapeutic approaches dictated by molecular alterations offers substantial promise for men with metastatic castration-resistant prostate cancer (mCRPC). However, current approaches for molecular characterization are primarily tissue based, necessitating serial biopsies to understand changes over time and are limited by the challenges inherent to extracting genomic material from predominantly bone metastases. Therefore, a circulating tumor cell (CTC)-based assay was developed to determine gene expression across a panel of clinically relevant and potentially actionable prostate cancer-related genes. CTCs were isolated from the whole blood of mCRPC patients (n = 41) and multiplex qPCR was performed to evaluate expression of prostate cancer-related target genes (n = 78). A large fraction of patients (27/41, 66%) had detectable CTCs. Increased androgen receptor (AR) expression (70% of samples) and evidence of Wnt signaling (67% of samples) were observed. The TMPRSS2:ERG fusion was expressed in 41% of samples, and the aggressive prostate cancer-associated long noncoding RNA SChLAP1 was upregulated in 70%. WNT5a [HR 3.62, 95% confidence interval (CI), 1.63-8.05, P = 0.002], AURKA (HR 5.56, 95% CI, 1.79-17.20, P = 0.003), and BMP7 (HR 3.86, 95% CI, 1.60-9.32, P = 0.003) were independently predictive of overall survival (FDR < 10%) after adjusting for a panel of previously established prognostic variables in mCRPC (Halabi nomogram). A model including Halabi, WNT5a, and AURKA expression, termed the miCTC score, outperformed the Halabi nomogram alone (AUC = 0.89 vs. AUC = 0.70). Understanding the molecular landscape of CTCs has utility in predicting clinical outcomes in patients with aggressive prostate cancer and provides an additional tool in the arsenal of precision-based therapeutic approaches in oncology.Implications: Analysis of CTC gene expression reveals a clinically prognostic "liquid biopsy" signature in patients with metastatic castrate-resistance prostate cancer. Mol Cancer Res; 16(4); 643-54. ©2018 AACR.

Current cell-free DNA (cfDNA) next generation sequencing (NGS) precision oncology workflows are typically limited to targeted and/or disease-specific applications. In advanced cancer, disease burden and cfDNA tumor content are often elevated, yielding unique precision oncology opportunities. We sought to demonstrate the utility of a pan-cancer, rapid, inexpensive, whole genome NGS of cfDNA approach (PRINCe) as a precision oncology screening strategy via ultra-low coverage (~0.01x) tumor content determination through genome-wide copy number alteration (CNA) profiling. We applied PRINCe to a retrospective cohort of 124 cfDNA samples from 100 patients with advanced cancers, including 76 men with metastatic castration-resistant prostate cancer (mCRPC), enabling cfDNA tumor content approximation and actionable focal CNA detection, while facilitating concordance analyses between cfDNA and tissue-based NGS profiles and assessment of cfDNA alteration associations with mCRPC treatment outcomes. Therapeutically relevant focal CNAs were present in 42 (34%) cfDNA samples, including 36 of 93 (39%) mCRPC patient samples harboring AR amplification. PRINCe identified pre-treatment cfDNA CNA profiles facilitating disease monitoring. Combining PRINCe with routine targeted NGS of cfDNA enabled mutation and CNA assessment with coverages tuned to cfDNA tumor content. In mCRPC, genome-wide PRINCe cfDNA and matched tissue CNA profiles showed high concordance (median Pearson correlation = 0.87), and PRINCe detectable AR amplifications predicted reduced time on therapy, independent of therapy type (Kaplan-Meier log-rank test, chi-square = 24.9, p < 0.0001). Our screening approach enables robust, broadly applicable cfDNA-based precision oncology for patients with advanced cancer through scalable identification of therapeutically relevant CNAs and pre-/post-treatment genomic profiles, enabling cfDNA- or tissue-based precision oncology workflow optimization.

PurposeCabozantinib (XL184) is an orally bioavailable tyrosine kinase inhibitor with activity against MET and vascular endothelial growth factor receptor 2. We evaluated the activity of cabozantinib in patients with castration-resistant prostate cancer (CRPC) in a phase II randomized discontinuation trial with an expansion cohort.Patients and methodsPatients received 100 mg of cabozantinib daily. Those with stable disease per RECIST at 12 weeks were randomly assigned to cabozantinib or placebo. Primary end points were objective response rate at 12 weeks and progression-free survival (PFS) after random assignment.ResultsOne hundred seventy-one men with CRPC were enrolled. Random assignment was halted early based on the observed activity of cabozantinib. Seventy-two percent of patients had regression in soft tissue lesions, whereas 68% of evaluable patients had improvement on bone scan, including complete resolution in 12%. The objective response rate at 12 weeks was 5%, with stable disease in 75% of patients. Thirty-one patients with stable disease at week 12 were randomly assigned. Median PFS was 23.9 weeks (95% CI, 10.7 to 62.4 weeks) with cabozantinib and 5.9 weeks (95% CI, 5.4 to 6.6 weeks) with placebo (hazard ratio, 0.12; P < .001). Serum total alkaline phosphatase and plasma cross-linked C-terminal telopeptide of type I collagen were reduced by ≥ 50% in 57% of evaluable patients. On retrospective review, bone pain improved in 67% of evaluable patients, with a decrease in narcotic use in 56%. The most common grade 3 adverse events were fatigue (16%), hypertension (12%), and hand-foot syndrome (8%).ConclusionCabozantinib has clinical activity in men with CRPC, including reduction of soft tissue lesions, improvement in PFS, resolution of bone scans, and reductions in bone turnover markers, pain, and narcotic use.

Maximizing the quality and quantity of life among men with localized prostate cancer who are elderly and have competing comorbidities may be achieved more effectively, either by treating these patients definitively or by opting for observation rather than using primary androgen‐deprivation therapy. A better understanding of the optimal ways to de‐implement this low‐value cancer care appears to be warranted for both elderly patients, who have little to gain by it, and younger patients, who have more to lose by foregoing definitive treatment with surgery or radiation therapy. [ABSTRACT FROM AUTHOR]

The substantial biological heterogeneity of metastatic prostate cancer has hindered the development of personalized therapeutic approaches. Therefore, it is difficult to predict the course of metastatic hormone-sensitive prostate cancer (mHSPC), with some men remaining on first-line androgen deprivation therapy (ADT) for several years while others progress more rapidly. Improving our ability to risk-stratify patients would allow for the optimization of systemic therapies and support the development of stratified prospective clinical trials focused on patients likely to have the greatest potential benefit. Here, we applied a liquid biopsy approach to identify clinically relevant, blood-based prognostic biomarkers in patients with mHSPC. Gene expression indicating the presence of CTCs was greater in CHAARTED high-volume (HV) patients (52% CTChigh) than in low-volume (LV) patients (23% CTChigh; * p = 0.03). HV disease (p = 0.005, q = 0.033) and CTC presence at baseline prior to treatment initiation (p = 0.008, q = 0.033) were found to be independently associated with the risk of nonresponse at 7 months. The pooled gene expression from CTCs of pre-ADT samples found AR, DSG2, KLK3, MDK, and PCA3 as genes predictive of nonresponse. These observations support the utility of liquid biomarker approaches to identify patients with poor initial response. This approach could facilitate more precise treatment intensification in the highest risk patients. [ABSTRACT FROM AUTHOR]

Background. The antifungal drug itraconazole inhibits angiogenesis and Hedgehog signaling and delays tumor growth in murine prostate cancer xenograft models. We conducted a noncomparative, randomized, phase II study evaluating the antitumor efficacy of two doses of oral itraconazole in men with metastatic prostate cancer. Patients and Methods. We randomly assigned 46 men with chemotherapy-naïve metastatic castration-resistant prostate cancer (CRPC) to receive low-dose (200 mg/day) or high-dose (600 mg/day) itraconazole until disease progression or unacceptable toxicity. The primary endpoint was the prostate-specific antigen (PSA) progression-free survival (PPFS) rate at 24 weeks; a 45% success rate in either arm was prespecified as constituting clinical significance. Secondary endpoints included the progression-free survival (PFS) rate and PSA response rate (Prostate Cancer Working Group criteria). Exploratory outcomes included circulating tumor cell (CTC) enumeration, serum androgen measurements, as well as pharmacokinetic and pharmacodynamic analyses. Results. The high-dose arm enrolled to completion (n 29), but the low-dose arm closed early (n17) because of a prespecified futility rule. The PPFS rates at 24 weeks were 11.8% in the low-dose arm and 48.0% in the high-dose arm. The median PFS times were 11.9 weeks and 35.9 weeks, respectively. PSA response rates were 0% and 14.3%, respectively. In addition, itraconazole had favorable effects on CTC counts, and it suppressed Hedgehog signaling in skin biopsy samples. Itraconazole did not reduce serum testosterone or dehydroepiandrostenedione sulfate levels. Common toxicities included fatigue, nausea, anorexia, rash, and a syndrome of hypokalemia, hypertension, and edema. Conclusion. High-dose itraconazole (600 mg/day) has modest antitumor activity in men with metastatic CRPC that is not mediated by testosterone suppression. [ABSTRACT FROM AUTHOR]

BACKGROUND: Mitoxantrone plus prednisone and ixabepilone each have modest activity as monotherapy for second-line chemotherapy in patients with docetaxel-refractory castration-resistant prostate cancer. Clinical noncrossresistance was previously observed. Phase 1 testing determined the maximum tolerated dose and dose-limiting toxicities with the combination regimen; a phase 2 study was conducted to evaluate the activity of the combination. METHODS: Patients with metastatic progressive castration-resistant prostate cancer during or after 3 or more cycles of taxane-based chemotherapy enrolled in a phase 2 multicenter study of ixabepilone 35 mg/m² and mitoxantrone 12 mg/m² administered on Day 1 every 21 days with pegfilgrastim support, along with prednisone 5 mg twice daily. Patients were evaluated for disease response and toxicity. RESULTS: Results are reported for the 56 evaluable patients. Twenty-five (45%; 95% confidence interval [CI], 31%-59%) experienced confirmed ≥50% prostate-specific antigen (PSA) declines, 33 (59%; 95% CI, 45%-72%) experienced confirmed ≥30% PSA declines, and 8 of 36 patients (22%; 95% CI, 10%-39%) with measurable disease experienced objective responses. Median time to PSA or objective progression was 4.4 months (95% CI, 3.5-5.6), and median progression-free survival was also 4.4 months (95% CI, 3.0-6.0). Median overall survival was 12.5 months (95% CI, 10.2-15.9). Thirty-two percent of patients experienced grade 3 of 4 neutropenia, and 11% experienced grade 3 or higher neutropenic infections, including 1 treatment-related death. Grade 2 and 3 neuropathy occurred in 11% and 12.5% of patients, respectively. CONCLUSIONS: These results suggest that the combination of ixabepilone and mitoxantrone is both feasible and active in castration-resistant prostate cancer and requires dosing with pegfilgrastim. [ABSTRACT FROM AUTHOR]

The article discusses the phase two trial that aimed to evaluate the efficacy of vorinostat in chemotherapy-treated patients with metastatic castration-resistant prostate cancer. Patients with disease progression were treated orally with 400 milligrams of vorinostat daily. The study observed that there was no decline in prostate-specific antigen and some patients experienced adverse events. Researchers concluded that vorinostat was associated with toxicities that limit its efficacy.

Purpose: This phase I-II study evaluated the safety, clinical activity and immunogenicity of an immunotherapy developed from human prostate cancer cell lines (PC-3 and LNCaP) modified to secrete granulocyte-macrophage colony-stimulating factor. Materials and Methods: Patients with noncastrate prostate cancer (19) with biochemical (prostate specific antigen) recurrence following prostatectomy or radiation therapy and no radiological evidence of metastasis were enrolled in the study. Patients were injected with an initial dose of 5 × 108 cells followed by 12 biweekly administrations of 1 × 108 cells. The adverse event profile, prostate specific antigen response, changes in prostate specific antigen kinetics and immunogenicity were assessed. Results: Immunotherapy was well tolerated with no serious treatment related adverse events and no autoimmune reactions. A negative deflection in prostate specific antigen slope was observed in 84% of patients after treatment with a significant increase in median prostate specific antigen doubling time from 28.7 weeks before treatment to 57.1 weeks after treatment (p = 0.0095). Median time to prostate specific antigen progression was 9.7 months. Immunoblot analysis of patient serum demonstrated new or enhanced production of PC-3 or LNCaP reactive antibodies in 15 of 19 (79%) patients after immunotherapy. Induction of antibody responses reactive against PC-3 in general, and to the PC-3 associated filamin-B protein specifically, were positively associated with treatment associated changes in prostate specific antigen kinetics. Conclusions: Granulocyte-macrophage colony-stimulating factor secreting cellular immunotherapy has a favorable toxicity profile with signals of clinical and immunological activity against hormone naïve prostate cancer. An association between immune response and prostate specific antigen changes was observed. Phase 3 trials in patients with advanced, metastatic, hormone refractory prostate cancer are under way. [Copyright &y& Elsevier]

Background: Few intervention studies have been conducted to help couples manage the effects of prostate cancer and maintain their quality of life. The objective of this study was to determine whether a family-based intervention could improve appraisal variables (appraisal of illness or caregiving, uncertainty, hopelessness), coping resources (coping strategies, self-efficacy, communication), symptom distress, and quality of life in men with prostate cancer and their spouses.Methods: For this clinical trial, 263 patient-spouse dyads were stratified by research site, phase of illness, and treatment; then, they were randomized to the control group (standard care) or the experimental group (standard care plus a 5-session family intervention). The intervention targeted couples' communication, hope, coping, uncertainty, and symptom management. The final sample consisted of 235 couples: 123 couples in the control group and 112 couples in the experimental group. Data collection occurred at baseline before randomization and at 4 months, 8 months, and 12 months.Results: At 4-month follow-up, intervention patients reported less uncertainty and better communication with spouses than control patients, but they reported no other effects. Intervention spouses reported higher quality of life, more self-efficacy, better communication, and less negative appraisal of caregiving, uncertainty, hopelessness, and symptom distress at 4 months compared with controls, and some effects were sustained to 8 months and 12 months.Conclusions: Men with prostate cancer and their spouses reported positive outcomes from a family intervention that offered them information and support. Programs of care need to be extended to spouses who likely will experience multiple benefits from intervention. [ABSTRACT FROM AUTHOR]

Objective: Preclinical studies suggest antiangiogenesis strategies may be effective in the treatment of prostate cancer. In tumor models, the copper-chelating agent tetrathiomolybdate (TM) has been shown to be antiangiogenic. We evaluated the antitumor activity of TM in patients with hormone-refractory prostate cancer (HRPC). Methods: Nineteen patients with asymptomatic HRPC enrolled. Copper depletion was monitored using serum ceruloplasmin levels. Once the target ceruloplasmin level of 5–15 mg/dl was attained, patients underwent staging evaluation. Patients were reassessed every 12 weeks, and TM was continued until they developed evidence of disease progression or intolerable toxicity. Prostate-specific antigen and levels of vascular endothelial growth factor, basic fibroblast growth factor, interleukin (IL)-6 and IL-8 were measured at study entry, at the time of copper depletion, and monthly while on therapy. Results: Seventeen of 19 patients achieved copper deficiency on TM therapy. Of the 16 evaluable patients, 14 developed progressive disease, 1 discontinued therapy because of toxicity and 1 patient opted to discontinue therapy because of rising prostate-specific antigen level without objective evidence of progressive disease. Levels of vascular endothelial growth factor, IL-6 and IL-8, but not basic fibroblast growth factor, were elevated when compared to normal controls prior to TM therapy, but there was no significant change during therapy. There was no correlation between prostate-specific antigen and levels of angiogenesis factors. Conclusions: Copper depletion with TM did not delay disease progression in patients with asymptomatic metastatic HRPC. Copyright © 2006 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

The article focuses on two hallmark studies that demonstrates a survival advantage in androgen-independent prostate cancer patients utilizing docetaxel chemotherapy in the U.S. Multiple mechanisms of androgen independence have now been documented including amplification of the androgen receptor as well as signal transduction pathways that bypass the androgen receptor completely.

: ObjectivesTo evaluate the efficacy and safety of neoadjuvant docetaxel and estramustine in patients with high-risk, newly diagnosed, prostate cancer.: MethodsEligible patients had prostate cancer with one or more of the following criteria: clinical Stage T2b or greater, prostate-specific antigen (PSA) of 15 ng/mL or greater, and/or Gleason score of 8 to 10. Chemotherapy consisted of docetaxel (70 mg/m2) on day 1 and estramustine (280 mg three times daily) on days 1 to 3 every 21 days for three to six courses. This was followed by local therapy, as deemed appropriate.: ResultsTwenty-one patients with a median age of 60 years, median PSA level of 16.1 ng/mL (range 2.4 to 175), and median baseline testosterone of 3.4 ng/mL were enrolled. Seven patients met one of the inclusion criteria, 10 met two, and 4 met three. The Gleason score was 8 or greater in 14 patients. A median of five cycles of chemotherapy was delivered. The most frequent high-grade toxicities were grade 3 (8 patients) and 4 (1 patient) neutropenia and deep venous thrombosis (grade 3 in 2 patients) before institution of low-dose warfarin. All patients responded as determined by protocol-defined criteria. Ten patients underwent radical prostatectomy, with negative surgical margins in 7 patients, and 11 received radiotherapy with negative preradiotherapy biopsies in 2.: ConclusionsInduction docetaxel and estramustine is well tolerated and feasible in patients with newly diagnosed, high-risk prostate cancer. This combination is active; however, its efficacy relative to hormonal therapy will require a controlled randomized trial. [Copyright &y& Elsevier]

Rates of progression and treatment response in advanced prostate cancer are highly variable, necessitating non‐invasive methods to assess the molecular characteristics of these tumors in real time. The unique potential of circulating tumor cells (CTCs) to serve as a clinically useful liquid biomarker is due to their ability to inform via both enumeration and RNA expression. A microfluidic graphene oxide‐based device (GO Chip) is used to isolate CTCs and CTC clusters from the whole blood of 41 men with metastatic castration‐resistant prostate cancer. Additionally, the expression of 96 genes of interest is determined by RT‐qPCR. Multivariate analyses are conducted to determine the genes most closely associated with overall survival, PSA progression, and radioclinical progression. A preliminary signature, comprising high expression of stemness genes and low expression of epithelial and mesenchymal genes, potentially implicates an undifferentiated CTC phenotype as a marker of poor prognosis in this setting. A microfluidic graphene oxide‐based device (GO Chip) is used to isolate circulating tumor cells (CTCs) and CTC clusters from the whole blood of 41 metastatic castration‐resistant prostate cancer patients. A preliminary RNA signature, comprising high expression of stemness genes and low expression of epithelial and mesenchymal genes, potentially implicates an undifferentiated CTC phenotype as a marker of poor prognosis. [ABSTRACT FROM AUTHOR]

Examines the expression of nuclear antigen Ki-67 in prostate cancer needle biopsy and radical prostatectomy specimens. Levels of expression in normal prostate tissue, high-grade prostatic intraepithelial neoplasia and prostate adenocarcinoma; Degree to which Ki-67 biomarker expression in sextant needle biopsy specimens.

Objective: To aid in the diagnosis and treatment of patients with metastatic tumor seeding, an exceedingly rare phenomenon following minimally invasive urological surgery, additional case reports are needed.Materials and Methods: We report our experience with patients determined to have peritoneal carcinomatosis following robotic-assisted radical prostatectomy (RARP) and provide a descriptive summary of these unique cases.Results: Five cases of peritoneal carcinomatosis were identified, all of which occurred relatively late-between 8 and 13 years-following RARP. Four of the 5 cases had T3 disease at the time of prostatectomy. 68Ga-PSMA PET identified peritoneal carcinomatosis in 3 of 5 cases.Conclusion: Certain clinical factors, such as advanced pathologic stage at the time of prostatectomy, may predict risk for carcinomatosis following RARP. Additionally, next-generation imaging modalities, such as PSMA PET, may aid in identifying these metastases and are likely to identify increasing numbers of these patients as next-generation imaging becomes more widely available. Continued documentation and classification of this atypical presentation are needed to improve our understanding and management of this phenomenon. [ABSTRACT FROM AUTHOR]

A recent phase III trial of the MET kinase inhibitor cabozantinib in men with castration-resistant prostate cancer (CRPC) failed to meet its primary survival end point; however, most men with CRPC have intact androgen receptor (AR) signaling. As previous work supports negative regulation of MET by AR signaling, we hypothesized that intact AR signaling may have limited the efficacy of cabozantinib in some of these patients. To assess the role of AR signaling on MET inhibition, we first performed an in silico analysis of human CRPC tissue samples stratified by AR signaling status (+ or -), which identified MET expression as markedly increased in AR- samples. In vitro, AR signaling inhibition in AR+ CRPC models increased MET expression and resulted in susceptibility to ligand (HGF) activation. Likewise, MET inhibition was only effective in blocking cancer phenotypes in cells with MET overexpression. Using multiple AR+ CRPC in vitro and in vivo models, we showed that combined cabozantinib and enzalutamide (AR antagonist) treatment was more efficacious than either inhibitor alone. These data provide a compelling rationale to combine AR and MET inhibition in CRPC and may explain the negative results of the phase III cabozantinib study in CRPC. Similarly, the expression of MET in AR- disease, whether due to AR inhibition or loss of AR signaling, suggests potential utility for MET inhibition in select patients with AR therapy resistance and in AR- prostate cancer. [ABSTRACT FROM AUTHOR]

: ObjectivesTo estimate in a pilot study the risk of being diagnosed with prostate cancer after exposure to Agent Orange in a clinical population of military veterans. Prostate cancer is the most common cancer diagnosed in American men and the second leading cause of cancer deaths. An association between Agent Orange and prostate cancer has been suggested by epidemiologic studies.: MethodsA case-control study was conducted at the Department of Veterans Affairs Medical Center in Ann Arbor, Michigan. Cases of pathologically diagnosed prostate cancer were identified and age matched in a 1:3 ratio with controls. Exposure to Agent Orange was assessed by reviewing the administrative portion of the computerized medical records. A subanalysis of the cases was conducted to examine the clinical features of prostate cancer in men reporting exposure to Agent Orange versus those who did not report exposure.: ResultsA total of 47 military veterans with prostate cancer and 142 control men without prostate cancer were selected. After adjusting for age and race, men with prostate cancer were approximately two times more likely to report previous exposure to Agent Orange (odds ratio 2.06; 95% confidence interval 0.81 to 5.23).: ConclusionsThe results from this pilot study suggest exposure to Agent Orange is associated with an increased risk of prostate cancer. Additional study in larger populations is necessary to confirm and to quantify this association more accurately. [Copyright &y& Elsevier]