[Long-term outcomes of prostate cancer patients with lymph nodes metastasis after radical prostatectomy and pelvic lymph node dissection]

TBX1 Functions as a Tumor Activator in Prostate Cancer by Promoting Ribosome RNA Gene Transcription

TBX1 belongs to an evolutionarily conserved family of transcription factors involved in organ development. TBX1 has been reported to have a hypermethylated cytosine guanine dinucleotide island around its second exon, which was related to prostate cancer (PCa) progression. However, the role and exact mechanism of TBX1 in PCa remains unknown. Using human prostate samples, online data mining and multiple in vitro and in vivo models, we examined the biological role and underlying mechanisms of TBX1 in PCa. TBX1 was highly expressed in PCa tissues, and high TBX1 expression was positively associated with Gleason score, pathological tumor stage, pathological lymph node stage, extraprostatic extension and disease/progression-free survival. In vitro and in vivo data demonstrated that TBX1 silencing inhibits PCa cell proliferation and colony formation and increases the cell population at the G0/G1 phase. The exogenous expression of TBX1 rescued these phenotypes. Mechanistically, TBX1 silencing suppressed the expression of 45S ribosomal RNA (rRNA), which was rescued by the exogenous expression of TBX1. TBX1 silencing inhibited the monomethylation of histone 3 lysine 4 (H3K4me1) binding with the non-coding intergenic spacer (IGS) regions of ribosomal DNA (rDNA) and the recruitment of upstream binding factor to the promoter and IGS regions of rDNA. The drug-induced enhancement of H3K4me1 counteracted the effect of TBX1 silencing. These findings indicate that TBX1 exerts its tumor activator function in PCa cells via epigenetic control, thereby promoting rRNA gene transcription. Thus, TBX1 may represent a prognostic biomarker and therapeutic target for PCa patients.

[When to introduce hormone therapy after total prostatectomy with positive lymph nodes? Study of the factors influencing the time of introduction of hormone therapy]

INTRODUCTION

Adjuvant hormone therapy is the standard treatment after total prostatectomy with positive lymph node. However, this treatment has side effects and at the time of the PSA era and extensive lymph node dissection, this principle is questioned. The aim of this study is to describe the oncological characteristics of patients that may explain the delay in introducing hormone therapy in patients with positive lymph node.

METHODS

Monocentric, retrospective study of 161 patients from November 1988 to February 2018 in a single French University Hospital, having undergone radical prostatectomy with positive lymph nodes on pathology. For each patient, preoperative data (age, clinical stage, biopsy results, d'Amico classification) and postoperative data (pathological results, number of lymph nodes removed, number of positive lympnodes, recurrence free survival, specific survival and overall survival) were collected. The date of introduction of hormone therapy was noted and survival without hormonal therapy was established according to the Kaplan Meier curve. The pre- and post-operative oncological factors that could influence hormone therapy introduction were investigated with Chi² and Student tests (statistically significant when P<0.05).

RESULTS

The mean number of lymph nodes removed was 12 [1-40]. The mean number of positive lymph nodes was 2.5 [1-24], the mean percentage of positive lymph nodes was 25% (2.5-100). After a mean follow-up of 95 months (3-354), 88 patients (54.6%) had no hormonal treatment. The average time to hormonal treatment was 40 months [0-310]. At 3 years, survival without hormone therapy was 52% and 51% at 5 years. Only the percentage of positive lymphnodes appeared to be a significant predictor of the introduction of hormone therapy. (29.32% vs. 21.99%, P=0.047). Hormone-free survival was significantly higher in patients with lymph node involvement less than 25% (P<0.0001) or with less than 2 positive lymph nodes (P=0.0294).

CONCLUSION

Lymph node invasion is a factor of poor prognosis after total prostatectomy and leads to introduce hormone therapy. Our study identified the percentage and number of positive lymph nodes as factors that identify patients who may be delayed in introducing this hormone therapy.

LEVEL OF PROOF

3.

Prognostic Significance of Young Age and Non-Bone Metastasis at Diagnosis in Patients with Metastatic Prostate Cancer: a SEER Population-Based Data Analysis

Objective: This study compared the clinicopathological features and survival of metastatic prostate cancer (mPCa) after stratification by age and non-bone-related metastasis to identify prognostic factors.

Methods: Patients with mPCa between 2010 and 2015 were identified from the Surveillance, Epidemiology and End Results database and analyzed. The overall survival (OS) rate was assessed using the Kaplan-Meier curve and log-rank test as well as multivariate Cox regression analysis.

Results: Among the 10147 patients with mPCa, 5378 were classified as young (≤70 years), 3140 were classified as middle-aged (70-82 years), and 1629 were classified as elderly (> 82 years). The younger patients with a single site metastasis with non-regional lymph nodes (NRLN) had a better prognosis than those with bone metastasis [hazard ratio (HR), 0.59, 95% confidence interval (CI), 0.47-0.73, P < 0.001], whereas patients with liver metastasis had the worst OS rate (P = 0.001). Moreover, patients in the middle-aged group with NRLN or lung metastasis had a better prognosis than those with bone metastasis (P < 0.05). The OS rate of patient with bone + liver and bone + brain metastasis was poorer (P < 0.001) than those with bone + NRLN metastasis in the younger patients (P < 0.05). The elder patients with bone + lung metastasis had the worst OS (HR, 1.54; 95% CI, 1.25-1.90, P < 0.001), although the death risk of patients with bone + brain and bone + NRLN metastasis not significantly different (P > 0.05). However, the OS of the patients with bone + liver metastasis remained the worst (P < 0.001).

Conclusions: Prostate cancer patients with lung metastasis or younger patients (≤70 years old) with bone + lung metastases had better OS than patients with other types of metastasis or old age.

Oncological Outcomes of Open Radical Retropubic Prostatectomy in Ireland: A Single Surgeon's 5-Year Experience

Objectives  There is a little published data on the outcomes of radical prostatectomy in the Irish context. We aimed to determine the 5-year oncological results of open radical retropubic prostatectomy (RRP) performed by a single surgeon following appointment. Methods  A retrospective review of RRPs performed between 2011 and 2016 was conducted. Patient demographics, preoperative parameters (clinical stage on digital rectal exam, prostate-specific antigen (PSA) levels, biopsy Gleason's score and MRI [magnetic resonance imaging] findings), pathological variables (T-stage, Gleason's score, nodal status, and surgical margin status), and treatment decisions (lymphadenectomy or adjuvant radiotherapy) were recorded. Oncological outcome at last follow-up was ascertained. Results  265 patients underwent RRP between 2011 and 2016. Median age was 62 years (range: 41-74). Mean follow-up was 32.24 months (range: 8-72) months. Pathological disease stage was T2 in 170/265 (64.15%), T3a in 65/265 (24.53%), and T3b in 30/265 (11.32%). Final Gleason's score was upgraded from diagnostic biopsy in 16.35% (43/263) and downgraded in 27% (71/263). Pelvic lymph node dissection was performed in 44.25% (118/265) patients. A positive surgical margin (PSM) was seen in 26/170 (15.2%) patients with T2 disease and in 45/95 (47.37%) patients with T3 disease. Of the 265 patients, 238 (89.81%) were disease-free at last follow-up, of whom 24/238 (10.08%) had received adjuvant and 17/238 (7.14%) received salvage radiotherapy. Adjuvant/salvage treatment was ongoing in 19/265 (7.17%) of patients. Conclusion  Good oncological outcomes of RRP in the Irish context are seen in this 5-year review, with the vast majority of patients experiencing biochemical-free survival at most recent follow-up.