OBJECTIVE: We hypothesized that Cav1.3 blockade by cinnarizine may achieve similar, or greater, reduction in aldosterone secretion than nonselective Cav1.2/1.3 blockade by nifedipine.
METHODS: Separate wells of angiotensin II-stimulated HAC15 cells were treated with either cinnarizine (1-30 μM) or nifedipine (1-100 μM). Aldosterone concentrations were measured in culture medium; RNA extraction and quantitative polymerase chain reaction were performed to evaluate CYP11B2 expression. A prospective, open-label, crossover study was conducted of 15 adults with PA, treated with 2 weeks of cinnarizine 30 mg 3 times a day or nifedipine extended release 60 mg daily, separated by a 2-week washout. The hierarchical primary outcome was change in aldosterone-to-renin ratio (ARR), urinary tetrahydroaldosterone (THA), and plasma aldosterone concentration (PAC). Blood pressure change was a secondary outcome. Parametric analysis was undertaken on log-transformed data. (ClinicalTrials.gov: NCT05686993).
RESULTS: Both drugs reduced aldosterone concentrations and CYP11B2 expression in vitro. Mean changes ± SEM in fold change of aldosterone concentrations and CYP11B2 were -0.47 ± 0.05 and -0.56 ± 0.07, respectively, with cinnarizine 30 μM and -0.59 ± 0.05 and -0.78 ± 0.07 with nifedipine 100 μM. In the clinical crossover trial, ARR was reduced by nifedipine but not cinnarizine (F = 3.25; P = .047); PAC rose with both drugs (F = 4.77; P = .013), but urinary THA was unchanged.
CONCLUSION: A Cav1.3 ligand, cinnarizine, reduced aldosterone secretion from adrenocortical cells, but at maximum-soluble concentrations was less effective than the nonselective calcium blocker, nifedipine. At clinical doses, cinnarizine did not reduce plasma ARR in patients with PA, and, as in vitro, was inferior to nifedipine. The limited efficacy of high-dose nifedipine may be due to incomplete Cav1.3 blockade, or to a role for non-L-type calcium channels in aldosterone secretion.
METHODS: PSAV was calculated using logistic regression to determine if PSA or PSAV predicted the result of prostate biopsy (PB) in men with elevated PSA values. Cox regression was used to determine whether PSA or PSAV predicted PSA elevation in men with low PSAs. Interaction terms were included in the models to determine whether BRCA status influenced the predictiveness of PSA or PSAV.
RESULTS: 1634 participants had ⩾3 PSA readings of whom 174 underwent PB and 45 PrCas diagnosed. In men with PSA >3.0 ng ml-l, PSAV was not significantly associated with presence of cancer or high-grade disease. PSAV did not add to PSA for predicting time to an elevated PSA. When comparing BRCA1/2 carriers to non-carriers, we found a significant interaction between BRCA status and last PSA before biopsy (P=0.031) and BRCA2 status and PSAV (P=0.024). However, PSAV was not predictive of biopsy outcome in BRCA2 carriers.
CONCLUSIONS: PSA is more strongly predictive of PrCa in BRCA carriers than non-carriers. We did not find evidence that PSAV aids decision-making for BRCA carriers over absolute PSA value alone.
OBJECTIVE: To report the utility of PSA screening, PrCa incidence, positive predictive value of PSA, biopsy, and tumour characteristics after 3 yr of screening, by BRCA status.
DESIGN, SETTING, AND PARTICIPANTS: Men aged 40-69 yr with a germline pathogenic BRCA1/2 mutation and male controls testing negative for a familial BRCA1/2 mutation were recruited. Participants underwent PSA screening for 3 yr, and if PSA > 3.0 ng/ml, men were offered prostate biopsy.
OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: PSA levels, PrCa incidence, and tumour characteristics were evaluated. Statistical analyses included Poisson regression offset by person-year follow-up, chi-square tests for proportion t tests for means, and Kruskal-Wallis for medians.
RESULTS AND LIMITATIONS: A total of 3027 patients (2932 unique individuals) were recruited (919 BRCA1 carriers, 709 BRCA1 noncarriers, 902 BRCA2 carriers, and 497 BRCA2 noncarriers). After 3 yr of screening, 527 men had PSA > 3.0 ng/ml, 357 biopsies were performed, and 112 PrCa cases were diagnosed (31 BRCA1 carriers, 19 BRCA1 noncarriers, 47 BRCA2 carriers, and 15 BRCA2 noncarriers). Higher compliance with biopsy was observed in BRCA2 carriers compared with noncarriers (73% vs 60%). Cancer incidence rate per 1000 person years was higher in BRCA2 carriers than in noncarriers (19.4 vs 12.0; p = 0.03); BRCA2 carriers were diagnosed at a younger age (61 vs 64 yr; p = 0.04) and were more likely to have clinically significant disease than BRCA2 noncarriers (77% vs 40%; p = 0.01). No differences in age or tumour characteristics were detected between BRCA1 carriers and BRCA1 noncarriers. The 4 kallikrein marker model discriminated better (area under the curve [AUC] = 0.73) for clinically significant cancer at biopsy than PSA alone (AUC = 0.65).
CONCLUSIONS: After 3 yr of screening, compared with noncarriers, BRCA2 mutation carriers were associated with a higher incidence of PrCa, younger age of diagnosis, and clinically significant tumours. Therefore, systematic PSA screening is indicated for men with a BRCA2 mutation. Further follow-up is required to assess the role of screening in BRCA1 mutation carriers.
PATIENT SUMMARY: We demonstrate that after 3 yr of prostate-specific antigen (PSA) testing, we detect more serious prostate cancers in men with BRCA2 mutations than in those without these mutations. We recommend that male BRCA2 carriers are offered systematic PSA screening.