¿Es el intervalo libre de docetaxel un factor predictivo para el cáncer de próstata resistente a la castración?

ObjectiveProstate cancer (PCa) is the second most common solid tumor in men and the fifth leading cause of cancer-related death. In advanced stage, palliative treatments are used instead of curative therapies. Therefore, finding predictive indicators seems crucial. Patients with castration-resistant prostate cancer (CRPC) that received Dx chemotherapy have been retrospectively reviewed. The aim of this study was to investigate whether docetaxel (Dx)-free interval could have a predictive value for PCa and influence other sequential therapies.Material and methodsThis clinical trial study was performed on 104 patients at Medeniyet University Oncology Clinic in 2018-2020. All CRPC patients had metastases, received Dx as first-line treatment and underwent androgen receptor axis targeted (ARAT) therapy after disease progression. We analyzed patients’ progression time after Dx therapy and the effects on sequential treatment.ResultsAfter Dx therapy, all patients received ARAT (abiraterone (ABI) n: 49 (47.1%) and enzalutamide (ENZ) n: 54 (51.9%)) as a second-line treatment, except for one patient who received cabazitaxel. There was a statistically significant relationship between the Dx-free interval and duration of response to ARAT (P<.001). The response time of ARAT treatment was <10.5 months in all patients whose Dx-free interval period was <9 months.ConclusionsOur findings support the theory that Dx-free interval can be a predictive factor for CRPC. CRPC disease can be classified as Dx-sensitive disease or Dx-resistance disease, based on the Dx-free interval. Decision on subsequent treatments could be made considering this information.     

Phase Ib dose-finding study of abiraterone acetate plus buparlisib (BKM120) or dactolisib (BEZ235) in patients with castration-resistant prostate cancer

BackgroundThe phosphatidylinositol-3-kinase (PI3K)/protein kinase B (Akt) signalling axis and androgen receptor (AR) pathways exhibit reciprocal feedback regulation in phosphatase and tensin homologue (PTEN)-deficient metastatic castration-resistant prostate cancer (CRPC) in preclinical models. This phase Ib study evaluated the pan-PI3K inhibitor buparlisib (BKM120) and the dual pan-PI3K/ mammalian target of rapamycin (mTOR) inhibitor dactolisib (BEZ235) in combination with abiraterone acetate (AA) in patients with CRPC.Materials and methodsPatients with CRPC who had progressed on AA therapy received escalating doses of either buparlisib or dactolisib, along with fixed doses of AA (1000 mg once daily (qd)) and prednisone (5 mg twice daily (bid)). The primary objective was to define the maximum tolerated dose (MTD) and/or the recommended dose for expansion (RDE) of either buparlisib or dactolisib in combination with AA. Secondary objectives included safety, antitumour activity (Prostate Cancer Working Group 2 (PCWG2) criteria; 30% of prostate-specific antigen (PSA) decline at ≥week 12) and pharmacokinetic (PK) profile.ResultsIn buparlisib + AA arm, 25 patients received buparlisib + AA (median age, 67 years; Eastern Cooperative Oncology Group performance status (ECOG PS) of 0/1/2 for 7/17/1 patients, respectively). At 100 mg qd; two patients experienced dose-limiting toxicities (DLTs) (grade 3 hyperglycaemia; grade 2 asthenia), and this was the maximum buparlisib dose explored. Buparlisib + AA showed a 26% lower median area under the curve from time zero to 24°h (AUC_0–24) and 48% lower median maximum serum concentration (Cmax) versus the single-agent buparlisib assessed in first-in-human study. No objective response and few PSA decreases were reported.In dactolisib + AA arm, 18 patients (median age, 71 years; ECOG PS of 0/1 for 6/12 patients, respectively) received dactolisib + AA at the first dose level (200 mg bid). Five patients had 9 DLTs (grades 2&3 stomatitis; grade 3 hyperglycaemia; grades 2& 3 diarrhoea; grades 1& 2 pyrexia, grade 2 vomiting, and grade 2 chills).ConclusionsBased on the assessment of available pharmacokinetics, safety, and efficacy data, no further study is planned for either buparlisib or dactolisib in combination with AA in CRPC.     

Prostate-specific antigen kinetic profiles during androgen deprivation therapy as prognostic factors in castration-resistant prostate cancer

ObjectiveTo identify pretreatment prognostic factors for patients with castration-resistant prostate cancer (CRPC) undergoing docetaxel (DCT) chemotherapy.Materials and methodsWe retrospectively analyzed 102 patients with CRPC who underwent DCT chemotherapy (dosage: 60–75 mg/m²) from December 2001 to August 2013. The parameters evaluated as prognostic factors were as follows: age, body mass index, Gleason score, clinical TNM stage, prior radical prostatectomy, prior radiation therapy, performance status, presence of pain, laboratory results at the start of DCT, and prostate-specific antigen (PSA) kinetics during prior androgen deprivation therapy (ADT), including PSA level at the start of ADT (PSA-ADT), PSA half-time (PSAT_1/2), time to nadir, PSA level at nadir (PSA-Nadir), duration of nadir, PSA doubling time (PSADT), and PSA level at the start of DCT (PSA-DCT). Univariate and multivariate analyses were performed to identify independent prognostic factors.ResultsMedian cancer-specific survival (CSS) duration following CRPC diagnosis was 28.0 months. In univariate analyses, performance status, serum albumin, serum creatinine, PSAT_1/2, time to nadir, PSA-Nadir, duration of nadir, PSADT, and PSA-DCT showed a potential association with prognosis (P<0.001–0.077). Multivariate analyses of these parameters showed that performance status (hazard ratio [HR] = 0.046; P = 0.046), serum creatinine (HR = 3.028; P = 0.036), PSAT_1/2 (HR = 0.172; P = 0.007), PSA-Nadir (HR = 4.884; P = 0.033), PSADT (HR = 0.148; P<0.001), and PSA-DCT (HR = 5.222; P = 0.004) remained independent predictors of CSS in CRPC.ConclusionsPSA kinetic parameters measured during prior ADT are significant surrogate markers predicting CSS in patients undergoing DCT chemotherapy for CRPC.     

A Randomized,Double-Blind,Dose-Finding,Multicenter, Phase 2 Study of Radium Chloride (Ra 223) in Patients with Bone Metastases and Castration-Resistant Prostate Cancer

Background

Patients with castration-resistant prostate cancer (CRPC) and bone metastases have an unmet clinical need for effective treatments that improve quality of life and survival with a favorable safety profile.

Objective

To prospectively evaluate the efficacy and safety of three different doses of radium chloride (Ra 223) in patients with CRPC and bone metastases.

Design, setting, and participants

In this phase 2 double-blind multicenter study, 122 patients were randomized to receive three injections of Ra 223 at 6-wk intervals, at doses of 25 kBq/kg (n = 41), 50 kBq/kg (n = 39), or 80 kBq/kg (n = 42). The study compared the proportion of patients in each dose group who had a confirmed decrease of ≥50% in baseline prostate-specific antigen (PSA) levels.

Outcome measurements and statistical analysis

Efficacy was evaluated using blood samples to measure PSA and other tumor markers, recorded skeletal-related events, and pain assessments. Safety was evaluated using adverse events (AEs), physical examination, and clinical laboratory tests. The Jonckheere-Terpstra test assessed trends between groups.

Results and limitations

The study met its primary end point with a statistically significant dose–response relationship in confirmed ≥50% PSA declines for no patients (0%) in the 25-kBq/kg dose group, two patients (6%) in the 50-kBq/kg dose group, and five patients (13%) in the 80-kBq/kg dose group (p = 0.0297). A ≥50% decrease in bone alkaline phosphatase levels was identified in six patients (16%), 24 patients (67%), and 25 patients (66%) in the 25-, 50-, and 80-kBq/kg dose groups, respectively (p < 0.0001). The most common treatment-related AEs (≥10%) occurring up to week 24 across all dose groups were diarrhea (21%), nausea (16%), and anemia (14%). No difference in incidence of hematologic events was seen among dose groups. Potential limitations include small patient numbers and differences among dose groups at baseline.

Conclusions

Ra 223 had a dose-dependent effect on serum markers of CRPC activity, suggesting that control of bone disease with Ra 223 may affect cancer-related outcomes. Ra 223 was well tolerated at all doses.

Trial registration

ClinicalTrials.gov: NCT00337155.     

氧化应激介导雄激素受体信号重激活在前列腺癌演进中的分子机制研究进展

晚期前列腺癌患者经过去势治疗后,体内产生大量的活性氧加重氧化应激。本文阐述了氧化应激调节雄激素受体（AR）及其信号通路的不同分子机制,例如氧化应激介导转录因子诱导AR过表达,导致瘤内局部雄激素水平升高,增加AR对低水平雄激素的敏感性以及诱导旁路途经导致AR激活,进而探究前列腺癌向去势抵抗性前列腺癌演进的分子机制,为势抵抗性前列腺癌的预防、诊断、治疗提供新的思路。     

Prostate-Specific Antigen Kinetics and Outcomes in Patients with Bone Metastases from Castration-Resistant Prostate Cancer Treated with or Without Zoledronic Acid

Background

Zoledronic acid (ZOL) is a standard therapy for the prevention of skeletal-related events (SREs) in patients with castration-resistant prostate cancer (CRPC). Although prostate-specific antigen (PSA) is an established marker for monitoring prostate cancer patients, correlations between PSA and disease outcomes during ZOL therapy are unclear.

Objective

To evaluate the relationships among PSA kinetics, bone-directed therapy with ZOL, and clinical outcomes in men with bone metastases from CRPC using a ZOL phase 3 trial database.

Design, setting, and participants

Exploratory analyses from a phase 3 trial in men with bone metastases from CRPC (n = 643) randomized to ZOL or placebo every 3 wk.

Outcome measurements and statistical analysis

PSA levels during the first 3 mo of the study were evaluated in linear and logarithmic (log) models stratified using prognostic factors established in a ZOL phase 3 trial and a CRPC nomogram. Relative risks of SREs, bone disease progression (BDP), and death were calculated per 1 log (nanograms per milliliter) PSA increase. Baseline PSA models used the study median (PSA: 77.3 ng/ml) as the high/low cut-off point.

Results and limitations

A total of 202 placebo- and 434 ZOL-treated patients were assessable. In both groups, PSA increases correlated with significantly increased risks of death, BDP, and first SRE. In the placebo and ZOL groups, associated increases in risk per 1 log (nanograms per milliliter) PSA increase were 29% (p < 0.0001) and 10% (p < 0.0074), respectively, for BDP, and 24% (p = 0.0010) and 13% (p = 0.0079), respectively, for first SRE. Limitations include the retrospective nature of these analyses and the potential confounding effects of concurrent antineoplastic therapies.

Conclusions

PSA is an important prognostic tool for survival in patients with bone metastases from CRPC, and these analyses show that PSA is also prognostic for BDP and SREs regardless of bone-targeted therapy.     

The Effect of Treatment Sequence on Overall Survival for Men With Metastatic Castration-resistant Prostate Cancer: A Multicenter Retrospective Study

IntroductionWe aimed to evaluate the treatment sequence for patients with metastatic castration-resistant prostate cancer (mCRPC) in real-world practice and compare overall survival in each sequential therapy.Patients and MethodsWe retrospectively evaluated 146 patients with mCRPC who were initially treated with androgen deprivation therapy as metastatic hormone-naive prostate cancer in 14 hospitals between January 2010 and March 2019. The agents for the sequential therapy included new androgen receptor-targeted agents (ART: abiraterone acetate or enzalutamide), docetaxel, and/or cabazitaxel. We evaluated the treatment sequence for mCRPC and the effect of sequence patterns on overall survival.ResultsThe median age was 71 years. A total of 35 patients received ART-ART, 33 received ART-docetaxel, 68 received docetaxel-ART, and 10 received docetaxel-cabazitaxel sequences. The most prescribed treatment sequence was docetaxel-ART (47%), followed by ART-ART (24%). Overall survival calculated from the initial diagnosis reached 83, 57, 79, and 37 months in the ART-ART, ART-docetaxel, docetaxel-ART, and docetaxel-cabazitaxel, respectively. Multivariate Cox regression analyses showed no significant difference in overall survival between the first-line ART (n = 68) and first-line docetaxel (n = 78) therapies (hazard ratio [HR], 0.84; P = .530), between the ART-ART (n = 35) and docetaxel-mixed (n = 111) sequences (HR, 0.82; P = .650), and between the first-line abiraterone (n = 32) and first-line enzalutamide (n = 36) sequences (HR, 1.58; P = .384).ConclusionThe most prescribed treatment sequence was docetaxel followed by ART. No significant difference was observed in overall survival among the treatment sequences in real-world practice.     

RNAi抑制PSA表达对前列腺癌22RV1细胞增殖和侵袭力的影响

目的 研究PSA表达对去势抵抗性前列腺癌22RV1细胞增殖和侵袭的影响.方法 构建含有针对PSA基因特异性短发夹RNA(shRNA,分别为shPSA1、shPSA2、shPSA3、shPSA4)和阴性对照序列(NC)的慢病毒载体并由慢病毒颗粒包装后,分别感染去势抵抗性前列腺癌22RV1细胞并筛选稳定表达PSA特异性shRNA的shPSA1-、shPSA2-、shPSA3-、shPSA4-和表达NC序列的NC-22RV1细胞.分别应用实时荧光定量聚合酶链反应和Western blot检测shRNA对22RV1细胞中PSA mRNA及蛋白表达的影响;采用CCK-8法、Transwell侵袭试验和流式细胞术检测PSA基因沉默后的22RV1细胞增殖、侵袭和凋亡情况.结果 与NC-22RV1细胞相比,shPSA3-22RV1细胞的基因和蛋白表达水平的沉默效果最好;shPSA2组在24、48、72 h的吸光度值分别为(0.1564±0.0225)、(0.2438±0.0358)、(0.3641±0.0205),shPSA3组分别为(0.1069±0.0120)、(0.1588±0.0192)、(0.2534±0.0289),与NC组比较差异均有统计学意义(P<0.01);shPSA1、shPSA2、shPSA3组侵袭力分别为NC组的77.35%(P=0.002)、54.35%(P<0.001)、42.21%(P<0.001);shPSA2、shPSA3组凋亡率分别为(27.97±4.28)%(P=0.001)、(43.03±3.19)%(P<0.001),高于NC组[(16.77±0.59)%].结论 PSA具有促进去势抵抗性前列腺癌22RV1细胞的增殖和侵袭效应,抑制PSA表达后前列腺癌22RV1细胞凋亡增加.     

Targeted Next-generation Sequencing of Advanced Prostate Cancer Identifies Potential Therapeutic Targets and Disease Heterogeneity

Background

Most personalized cancer care strategies involving DNA sequencing are highly reliant on acquiring sufficient fresh or frozen tissue. It has been challenging to comprehensively evaluate the genome of advanced prostate cancer (PCa) because of limited access to metastatic tissue.

Objective

To demonstrate the feasibility of a novel next-generation sequencing (NGS)–based platform that can be used with archival formalin-fixed paraffin-embedded (FFPE) biopsy tissue to evaluate the spectrum of DNA alterations seen in advanced PCa.

Design, setting, and participants

FFPE samples (including archival prostatectomies and prostate needle biopsies) were obtained from 45 patients representing the spectrum of disease: localized PCa, metastatic hormone-naive PCa, and metastatic castration-resistant PCa (CRPC). We also assessed paired primaries and metastases to understand disease heterogeneity and disease progression.

Intervention

At least 50 ng of tumor DNA was extracted from FFPE samples and used for hybridization capture and NGS using the Illumina HiSeq 2000 platform.

Outcome measurements and statistical analysis

A total of 3320 exons of 182 cancer-associated genes and 37 introns of 14 commonly rearranged genes were evaluated for genomic alterations.

Results and limitations

We obtained an average sequencing depth of >900X. Overall, 44% of CRPCs harbored genomic alterations involving the androgen receptor gene (AR), including AR copy number gain (24% of CRPCs) or AR point mutation (20% of CRPCs). Other recurrent mutations included transmembrane protease, serine 2 gene (TMPRSS2):v-ets erythroblastosis virus E26 oncogene homolog (avian) gene (ERG) fusion (44%); phosphatase and tensin homolog gene (PTEN) loss (44%); tumor protein p53 gene (TP53) mutation (40%); retinoblastoma gene (RB) loss (28%); v-myc myelocytomatosis viral oncogene homolog (avian) gene (MYC) gain (12%); and phosphatidylinositol-4,5-bisphosphate 3-kinase, catalytic subunit α gene (PIK3CA) mutation (4%). There was a high incidence of genomic alterations involving key genes important for DNA repair, including breast cancer 2, early onset gene (BRCA2) loss (12%) and ataxia telangiectasia mutated gene (ATM) mutations (8%); these alterations are potentially targetable with poly(adenosine diphosphate-ribose)polymerase inhibitors. A novel and actionable rearrangement involving the v-raf murine sarcoma viral oncogene homolog B1 gene (BRAF) was also detected.

Conclusions

This first-in-principle study demonstrates the feasibility of performing in-depth DNA analyses using FFPE tissue and brings new insight toward understanding the genomic landscape within advanced PCa.