Citations

Abstract Serum levels of miR-194 have been reported to predict prostate cancer recurrence after surgery, but its functional contributions to this disease have not been studied. Herein, it is demonstrated that miR-194 is a driver of prostate cancer metastasis. Prostate tissue levels of miR-194 were associated with disease aggressiveness and poor outcome. Ectopic delivery of miR-194 stimulated migration, invasion, and epithelial–mesenchymal transition in human prostate cancer cell lines, and stable overexpression of miR-194 enhanced metastasis of intravenous and intraprostatic tumor xenografts. Conversely, inhibition of miR-194 activity suppressed the invasive capacity of prostate cancer cell lines in vitro and in vivo. Mechanistic investigations identified the ubiquitin ligase suppressor of cytokine signaling 2 (SOCS2) as a direct, biologically relevant target of miR-194 in prostate cancer. Low levels of SOCS2 correlated strongly with disease recurrence and metastasis in clinical specimens. SOCS2 downregulation recapitulated miR-194–driven metastatic phenotypes, whereas overexpression of a nontargetable SOCS2 reduced miR-194–stimulated invasion. Targeting of SOCS2 by miR-194 resulted in derepression of the oncogenic kinases FLT3 and JAK2, leading to enhanced ERK and STAT3 signaling. Pharmacologic inhibition of ERK and JAK/STAT pathways reversed miR-194–driven phenotypes. The GATA2 transcription factor was identified as an upstream regulator of miR-194, consistent with a strong concordance between GATA2 and miR-194 levels in clinical specimens. Overall, these results offer new insights into the molecular mechanisms of metastatic progression in prostate cancer. Cancer Res; 77(4); 1021–34. ©2016 AACR.

BACKGROUNDA new prostate cancer (PCa) grading system (namely, Gleason score‐GS‐ ≤6 vs. 3 + 4 vs. 4 + 3 vs. 8 vs. ≥9) was recently proposed and assessed on biochemical recurrence (BCR) showing improved predictive abilities compared to the commonly used three‐tier system (GS ≤6 vs. 7 vs. ≥8). We assessed the predictive ability of the five‐tier grade group (GG) system on harder clinical endpoint, namely clinical recurrence (CR).METHODSBetween 2005 and 2014, 9,728 clinically localized PCa patients were treated with radical prostatectomy (RP) at two tertiary referral centers. Kaplan–Meier curves, multivariable Cox regression analyses, and concordance index (C‐index) were used to assess CR after treatment according to four Gleason grade classifications at biopsy and RP: Group 1: ≤6 versus 7 versus ≥8; Group 2: ≤6 versus 3 + 4 vs. 4 + 3 versus ≥8; Group 3: ≤6 versus 7 versus 8 versus ≥9; Group 4: ≤6 versus 3 + 4 versus 4 + 3 versus 8 versus ≥9. Same analyses were repeated in patients who had BCR (n = 1,624). Decision curve analyses were performed to evaluate and compare the net benefit associated with the use of the four Gleason grade classifications.RESULTSOverall, 443 (4.6%) patients had CR. The hazard ratio of the GS 3 + 4, 4 + 3, 8, and ≥9 relative to GS ≤6 were 3.63, 5.93, 11.44, 18.08 and 4.93, 9.99, 15.31 and 25.12 in the pre‐ and post‐treatment models, respectively. The C‐index of the five‐tier GG system was slightly higher relative to the other 3 Gleason grade classifications both in the pre‐ (range: 0.001–0.006) and post‐treatment models (range: 0–0.008). Similar findings were observed when we focused our analyses in patients with BCR after RP. The use of the five‐tier GG system did not result into higher net‐benefit relative to the other three Gleason grade classifications.CONCLUSIONSThe difference in accuracy between the five‐tier GG system and the other Gleason grade classifications, using CR as an endpoint, is clinically negligible. Current evidence suggests that the five‐tier GG system represents a simplified user‐friendly scheme available for patient counseling rather than a new histopathological diagnostic system that improves the prediction of CR. Prostate 77:263–273, 2017. © 2016 Wiley Periodicals, Inc.

Objective To investigate the long‐term utility of adjuvant therapy after radical prostatectomy ( RP ) for prostate cancer with seminal vesicle invasion ( SVI ; pT 3b), as the published data are conflicting. Patients and Methods Patients with SVI during RP and pelvic lymph node dissection at two major referral centres from 1986 to 2014 were included. Kaplan–Meier analyses and multivariable Cox regressions were used to determine if adjuvant radiotherapy ( aRT ) and adjuvant hormonal therapy ( aHT ) were predictors of biochemical recurrence ( BCR ), cancer‐specific mortality ( CSM ) and overall mortality ( OM ). Subset analyses were performed for pN 0 patients and pN + patients. Results Overall, 3 279 patients with prostate cancer and SVI were included with a median follow‐up of 148 months. Considering the whole SVI population, 1 387 (42%) received no adjuvant therapy, 1 179 (36%) received aHT , 461 (14.1%) received aRT , while 252 (7.7%) received both aHT and aRT . The 10‐year BCR , CSM , and OM rates were 64%, 14%, and 27%, respectively. In the overall population, aRT and aHT were predictors of BCR , CSM and OM (all P < 0.04). When only pT 3bN0 patients were considered, aHT was a significant multivariate predictor of BCR [hazard ratio ( HR ) 0.50, P < 0.001), CSM ( HR 0.62, P = 0.01) and OM ( HR 0.75, P = 0.004). Conversely, aRT was not associated with survival outcomes (all P > 0.05). When only the subgroup pT 3bN+ was considered, the use of aRT was related to an improvement in CSM ( HR 0.65, P = 0.03) and OM (HR 0.78, P = 0.03). Conclusions aHT + aRT seems to be effective in pT 3b patients. However, when stratified according to the presence of nodal metastases, aHT remains effective only in the node‐negative subgroup, while aRT remains effective only in the node‐positive subgroup. Further data including prospective trials are warranted to study the utility of adjuvant therapies in this setting.

Abstract In the era of precision medicine, genomic classifications of prostate cancer (PC) have not broadly impacted patient care. Here we present an integrative transcriptome analysis of 14 disease-related pathways in over 4,600 clinical specimens and 25 PC preclinical models. This approach provides a novel classification scheme, inclusive of 3 PC subtypes (PCS1-3), which predict disease progression and drug resistance. The PCS1 and PCS2 categories possess characteristics of luminal cells, while PCS3 exhibits basal features. Castration-resistant and metastatic cancers are over-represented in PCS1 and PCS3 tumors. All 3 subtypes are represented in commonly used PC cell lines; however, none of the mouse models we analyzed resembles PCS3. PCS classification using RNA expression data appears to be stable across primary and metastatic human tumors, cell lines, xenografts and mouse models. This new subtyping method provides novel opportunities for patient stratification that reflect specific features of tumor biology and may influence therapeutic decisions. Citation Format: Sungyong You, Beatrice Knudsen, Nicholas Erho, Mohammed Alshalalfa, Mandeep Takhar, Hussam Al-deen Ashab, Elai Davicioni, Robert Jeffrey Karnes, Eric A. Klein, Robert B. Den, Ashley E. Ross, Edward M. Schaeffer, Isla P. Garraway, Jayoung Kim, Michael R. Freeman. Three intrinsic subtypes of prostate cancer with distinct pathway activation profiles differ in prognosis and treatment response. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 1502.