Development and validation of a cell cycle progression signature for decentralized testing of men with prostate cancer.

Aim: The 46-gene Prolaris® cell cycle progression test provides information on the risk of prostate cancer progression. Here we developed and validated a 16-gene kit-based version. Methods: RNA was extracted from prostate cancer biopsy tissue. Amplification efficiency, minimum tumor content, repeatability, reproducibility and equivalence with the 46-gene test were evaluated. Results: Amplification efficiencies for all genes were within the acceptable range (90-110%), and samples with ≥50% tumor content were appropriate for the 16-gene test. Results were repeatable (standard deviation: 0.085) and reproducible (standard deviation: 0.115). Instrument, operator and kit lot had minimal impact on results. Cell cycle progression scores from the 46- and 16-gene tests were highly correlated (r = 0.969; bias = 0.217). Conclusion: The 16-gene test performs consistently and similarly to the 46-gene test.

Prostate cancer does not always require aggressive treatment, and some men with low risk of disease progression may chose active surveillance. One way to measure the risk of disease progression is the Prolaris^® cell cycle progression test, which is performed at a commercial testing facility and measures the expression of 46 genes. However, certain European countries would prefer to run this test at a centralized testing facility. To this end we developed a streamlined kit measuring 16 genes to be used in these testing facilities, and showed that the cell cycle progression scores derived from the kit test are robust and equivalent to those obtained with the larger 46-gene test.

Comparison of EndoPredict and EPclin With Oncotype DX Recurrence Score for Prediction of Risk of Distant Recurrence After Endocrine Therapy.

BACKGROUND: Estimating distant recurrence (DR) risk among women with estrogen receptor-positive (ER+), human epidermal growth factor receptor 2 (HER2)-negative early breast cancer helps decisions on using adjuvant chemotherapy. The 21-gene Oncotype DX recurrence score (RS) is widely used for this. EndoPredict (EPclin) is an alternative test combining prognostic information from an eight-gene signature (EP score) with tumor size and nodal status. We compared the prognostic information provided by RS and EPclin for 10-year DR risk. METHODS: We used likelihood ratio χ² and Kaplan-Meier survival analyses to compare prognostic information provided by EP, EPclin, RS, and the clinical treatment score (CTS) of clinicopathologic parameters in 928 patients with ER+ disease treated with five years' anastrozole or tamoxifen. Comparisons were made for early (0-5 years) and late (5-10 years) DR according to nodal status. All statistical tests were two-sided. RESULTS: In the overall population, EP and EPclin provided substantially more prognostic information than RS (LRχ(2): EP = 49.3; LRχ(2): EPclin = 139.3; LRχ(2): RS = 29.1), with greater differences in late DR and in node-positive patients. EP and EPclin remained statistically significantly prognostic when adjusted for RS (ΔLRχ(2): EP+RS vs RS = 20.2; ΔLRχ(2): EPclin+RS vs RS = 113.8). Using predefined cut-offs, EPclin and RS identified 58.8% and 61.7% patients as low risk, with hazard ratios for non-low vs low risk of 5.99 (95% confidence interval [CI] = 3.94 to 9.11) and 2.73 (95% CI = 1.91 to 3.89), respectively. CONCLUSIONS: EP and EPclin were highly prognostic for DR in endocrine-treated patients with ER+, HER2-negative disease. EPclin provided more prognostic information than RS. This was partly but not entirely because of EPclin integrating molecular data with nodal status and tumor size.