Tumor formation of prostate cancer cells influenced by stromal cells from the transitional or peripheral zones of the normal prostate

This study was designed to investigate the different involvements of prostatic stromal cells from the normal transitional zone(TZ)or peripheral zone(PZ)in the carcinogenesis of prostate cancer(PCa)epithelial cells(PC-3)in vitro and in vivo co-culture models.Ultra-structures and gene expression profiles of primary cultures of human prostatic stromal cells from the normal TZ or PZ were analyzed by electron microscopy and microarray analysis.In vitro and in vivo co-culture models composed of normal TZ or PZ stromal cells and human PCa PC-3 cells were established.We assessed tumor growth and weight in the in vivo nude mice model.There are morphological and ultra-structural differences in stromal cells from TZ and PZ of the normal prostate.In all,514 differentially expressed genes were selected by microarray analysis;483 genes were more highly expressed in stromal cells from TZ and 31 were more highly expressed in those from PZ.Co-culture with PZ stromal cells and transforming growth factor-β1(TGF-β1)increased the tumor growth of PC-3 cells in vitro and in vivo,as well as Bcl-2 expression.On the other hand,stromal cells of TZ suppressed PC-3 cell tumor growth in the mouse model.We conclude that ultra-structures and gene expression differ between the stromal cells from TZ or PZ of the normal prostate,and stroma-epithelium interactions from TZ or PZ might be responsible for the distinct zonal localization of prostate tumor formation.

Chimeric molecules facilitate the degradation of androgen receptors and repress the growth of LNCaP cells

Post-translational degradation of protein plays an important role in cell life. We employed chimeric molecules （dihydrotestosterone-based proteolysis-targeting chimeric molecule [DHT-PROTAC]） to facilitate androgen receptor （AR） degradation via the ubiquitin-proteasome pathway （UPP） and to investigate the role of AR in cell proliferation and viability in androgen-sensitive prostate cancer cells. Western blot analysis and immunohistochemistry were applied to analyse AR levels in LNCaP cells after DHT-PROTAC treatment. Cell counting and the 3-（4,5-dimethylthiazol-2-yl）-2,5- diphenyl tetrazolium bromide （MTT） cell viability assay were used to evaluate cell proliferation and viability after AR elimination in both LNCaP and PC-3 cells. AR was tagged for elimination via the UPP by DHT-PROTAC, and this could be blocked by proteasome inhibitors. Degradation of AR depended on DHT-PROTAC concentration, and either DHT or an ALAPYIP-（arg）8 peptide could compete with DHT-PROTAC. Inhibition of cell proliferation and decreased viability were observed in LNCaP cells, but not in PC-3 or 786-0 cells after DHT-PROTAC treatment. These data indicate that AR elimination is facilitated via the UPP by DHT-PROTAC, and that the growth of LNCaP cells is repressed after AR degradation.

Differences in phenotype and gene expression of prostate stromal cells from patients of varying ages and their influence on tumour formation by prostate epithelial cells

Prostate cancer （PCa） is an age-related disease, and the stromal microenvironment plays an important role in prostatic malignant progression. However, the differences in prostate stromal cells present in young and old tissue are still obscure. We established primary cultured stromal cells from normal prostatic peripheral zone （PZ） of donors of varying ages and found that cultured stromal cells from old donors （PZ-old） were more enlarged and polygonal than those from young donors （PZ-young）. Furthermore, based on immunocytochemical and ultrastructural analysis, the components of stromal cells changed from a majority of fibroblasts to a mixture of fibroblasts and myofibroblasts with increasing donor age. Using a three-dimensional in vitro culture system, we found that PZ-old stromal cells could enhance the proliferation, migration and invasion of cocultured benign BPH-1 and PC-3 cells. Using an in vivo tissue recombination system, we also found that PZ-old stromal cells are more effective than PZ-young cells in promoting tumour formation by BPH-1 cells of high passage（〉100） and PC-3 cells. To probe the possible mechanism of these effects, we performed cDNA microarray analysis and profiled 509 upregulated genes and 188 downregulated genes in PZ-old cells. Among the changed genes, we found genes coding for a subset of paracrine factors that are capable of influencing adjacent epithelial cells; these include hepatocyte growth factor （HGF）, fibroblast growth factor 5 （FGF5）, insulin-like growth factor 2 （IGF2）, insulin-like growth factor-binding protein 4 （IGFBP4）, IGFBP5 and matrix metallopeptidase 1 （MMP1）. Changes in the expression of these genes were further confirmed by quantitative real-time polymerase chain reaction （PCR）, Western blotting and enzyme-linked immunosorbent assays. Overall, our findings indicate that stromal cells from prostate PZ of old donors are more active than similar cells from young donors in promoting the malignant process of adjacent epithelial cells. This finding hints at a new potential strategy for the prevention of PCa.

Androgen receptors expressed by prostatic stromal cells obtained from younger versus older males exhibit opposite roles in prostate cancer progression

Aging is a major risk factor for prostate cancer （PCa）, and prostatic stromal cells may also promote PCa progression. Accordingly, stromal cells do not equally promote PCa in older males and younger males. Therefore, it is also possible that the expression of androgen receptors （ARs） by prostatic stromal cells in older versus younger males plays different roles in PCa progression. Using a gene knockdown technique and coculture system, we found that the knockdown of the AR in prostatic stromal cells obtained from younger males could promote the invasiveness and metastasis of cocultured PC3/LNCaP cells in vitro. By contrast, the invasiveness and metastasis of LNCaP cells was inhibited when cocultured with prostatic stromal cells from older males that when AR expression was knocked down. Moreover, after targeting AR expression with small hairpin RNA （shRNA）, matrix metalloproteinase （MMP） expression in stromal cells was observed to increase in the younger group, but decreased or remained unchanged in the older group. One exception, however, was observed with MMP9. In vivo, after knocking down AR expression in prostatic stromal cells, the incidence of metastatic lymph nodes was observed to increase in the younger age group, but decreased in the older age group. Together, these data suggest that the AR in prostatic stromal cells played opposite roles in PCa metastasis for older versus younger males. Therefore, collectively, the function of the AR in prostatic stromal cells appears to change with age, and this may account for the increased incidence of PCa in older males.

Strata-pressure behavior of double-unit mining method combining fully-mechanized and mechanized coal face

Based on the engineering background of double-unit face mining under complicated geological conditions and the lagging fully-mechanized face surpassing the fore mechanized face of double-unit face in Zhou Yuanshan coal mine, strata-pressure behavior in the process was analyzed based on FLAC3D and on-site measurement. The results show that the stress concentration factor of superposition abutment pressure and the alternate distance of double-unit face are meeting gauss function, the relationship between the depth of stress concentration point and alternate distance also meets gaussian function. When the alternate distance is larger than 24 m, the superimposition of pilot support pressure in the double-unit face is weak. When the alternate distance is more than 12-15 m, the changes of the roof subsidence coefficient and the depth of stress con- centration point are stabilized; when the alternate distance is 3-6 m, the fore working face end is in the greatest impact area of superposition abutment pressure, this area should be avoided in determining the reasonable alternate distance.

Comparison of diagnostic efficacy between transrectal and transperineal prostate biopsy:a propensity score-matched study

This study compared the diagnostic efficacy of transrectal ultrasound(TRUS)-guided prostate biopsy(TRBx)and transperineal prostate biopsy(TPBx)in patients with suspected prostate cancer(PCa).We enrolled 2962 men who underwent transrectal(n=1216)or transperineal(n=1746)systematic 12-core prostate biopsy.Clinical data including age,prostate-specific antigen(PSA)level,and prostate volume(PV)were recorded.To minimize confounding,we performed propensity score-matching analysis?We measured and compared PCa detection rates between TRBx and TPBx,which were stratified by clinical characteristics and Gleason scores.The effects of clinical characteristics on PCa detection rate were assessed by logistic regression.For all patients,TPBx detected a higher proportion of clinically significant PCa(P<0.001).Logistic regression analyses illustrated that PV had a smaller impact on PCa detection rate of TPBx compared with TRBx.Propensity score-matching analysis showed that the detection rates in TRBx were higher than those in TPBx for patients aged≥80 years(80.4%vs 56.5%,P=0.004)and with PSA level 20.1-100.0 ng ml^-1(80.8%vs 69.1%,P=0.040).In conclusion,TPBx was associated with a higher detection rate of clinically significant PCa than TRBx was;however,because of the high detection rate at certain ages and PSA levels,biopsy approaches should be optimized according to patents'clinical characteristics.

Two-micrometer thulium laser resection of the prostate-tangerine technique in benign prostatic hyperplasia patients with previously negative transrectal prostate biopsy

The 2-1μm thulium laser resection of the prostate-tangerine technique （TmLRP-TT） has been introduced as a minimally invasive treatment for benign prostatic hyperplasia （BPH）. This study was undertaken to assess the clinical efficacy and safety of TmLRP-TT for the treatment of BPH patients with previously negative transrectal prostate biopsy. A prospective analysis of 51 patients with previously negative transrectal prostate biopsy who underwent surgical treatment using TmLRP-TT was performed from December 2011 to December 2013. Preoperative status, surgical details, and perioperative complications were recorded. The follow-up outcome was evaluated with subjective and objective tests at I and 6 months. TmLRP-TT was successfully completed in all patients. Mean prostate volume, operative duration, and catheterization time were 93.3 ± 37.9 ml, 69.5 ± 39.5 min, and 6.5 ± 1.3 days, respectively. The mean International Prostate Symptom Score, quality of life score, maximum urinary flow rate, and post-void residual urine volume changed notably at 6-month follow-up （22.5 ± 6.9 vs 6.1 ± 3.2, 4.8 ± 1.3 vs 1.1 ± 0.9, 7.3 ± 4.5 vs 18.9 ± 7.1 ml s^-1, and 148.7 ± 168.7 vs 28.4 ± 17.9 ml）. Two （3.9%） patients required blood transfusion perioperatively, while 3 （5.9%） patients experienced transient hematuria postoperatively, and 2 （3.9%） patients received 3 days recatheterization due to clot retention. TmLRP-TT is a safe and effective minimally invasive technique for patients with previously negative transrectal prostate biopsy during the 6-month follow-up. This promising technology may be a feasible surgical method for previously negative transrectal prostate biopsy in the future.

Peripheral zone PSA density:a predominant variable to improve prostate cancer detection efficiency in men with PSA higher than 4 ng ml^(-1)

To improve the diagnostic efficiency of prostate cancer(PCa)and reduce unnecessary biopsies,we defined and analyzed the diagnostic efficiency of peripheral zone prostate-specific antigen(PSA)density(PZ-PSAD).Patients who underwent systematic 12-core prostate biopsies in Shanghai General Hospital(Shanghai,China)between January 2012 and January 2018 were retrospectively identified(n=529).Another group of patients with benign prostatic hyperplasia(n=100)were randomly preselected to obtain the PSA density of the non-PCa cohort(N-PSAD).Prostate volumes and transition zone volumes were measured using multiparameter magnetic resonance imaging(mpMRI)and were combined with PSA and N-PSAD to obtain the PZ-PSAD from a specific algorithm.Receiver operating characteristic(ROC)curve analysis was used to assess the PCa detection efficiency in patients stratified by PSA level,and the area under the ROC curve(AUC)of PZ-PSAD was higher than that of PSA,PSA density(PSAD),and transition zone PSA density(TZ-PSAD).PZ-PSAD could amend the diagnosis for more than half of the patients with inaccurate transrectal ultrasonography(TRUS)and mpMRI results.When TRUS and mpMRI findings were ambiguous to predict PCa(PIRADS score≤3),PZ-PSAD could increase the positive rate of biopsy from 21.7%to 54.7%,and help 63.8%(150/235)of patients avoid unnecessary prostate biopsy.In patients whose PSA was 4.0–10.0 ng ml^(−1),10.1–20.0 ng ml^(−1),and>20.0 ng ml^(−1),the ideal PZ-PSAD cut-off value for predicting clinically significant PCa was 0.019 ng ml^(−2),0.297 ng ml^(−2),and 1.180 ng ml^(−2),respectively(sensitivity>90%).Compared with PSA,PSAD,and TZ-PSAD,the efficiency of PZ-PSAD for predicting PCa is the highest,leading to fewer missed diagnoses and unnecessary biopsies.

Efficacy of stepwise mini-incision microdissection testicular sperm extraction for nonobstructive azoospermia with varied etiologies

Stepwise mini-incision microdissection testicular sperm extraction(mTESE)is a procedure that attempts to minimize testicular damage.However,the mini-incision approach may vary in patients with different etiologies.Here,we performed a retrospective analysis of 665 men with nonobstructive azoospermia(NOA)who underwent stepwise mini-incision mTESE(Group 1)and 365 men who underwent standard mTESE(Group 2).The results showed that the operation time(mean±standard deviation)for patients with successful sperm retrieval in Group1(64.0±26.6min)was significantly shorter than that in Group2(80.2±31.3min),with P<0.001.The total sperm retrieval rate(SRR)was 23.1%in our study,and there was no significant difference between Group 1 and Group 2(P>0.05),even when the etiologies of NOA were taken into consideration.The results of consecutive multivariate logistic regression analysis(odds ratio[0R]:0.57;95%confidence interval[Cl]:0.38-0.87;P=0.009)and receiver operating characteristic(ROC)analysis(area under the ROC curve[AUC]=O.628)showed that preoperative anti-Mullerian hormone(AMH)level in idiopathic NOA patients was a potential predictor for surgical outcomes after initial three small incisions made in the equatorial region without sperm examined under an operating microscope(Steps 2-4).In conclusion,stepwise mini-incision mTESE is a useful technique for NOA patients,with comparable SRR,less surgical invasiveness,and shorter operation time compared with the standard approach.Low AMH levels may predict successful sperm retrieval in idiopathic patients even after a failed initial mini-incision procedure.

Clinical features and microsurgical reconstruction of congenital unilateral absence of the vas deferens with obstructive azoospermia:a tertiary care center experience

Patients with congenital unilateral absence of the vas deferens(CUAVD)manifest diverse symptoms from normospermia to azoospermia.Treatment for CUAVD patients with obstructive azoospermia(OA)is complicated,and there is a lack of relevant reports.In this study,we describe the clinical features and evaluate the treatments and outcomes of CUAVD patients with OA.From December 2015 to December 2020,33 patients were diagnosed as CUAVD with OA in Shanghai General Hospital(Shanghai,China).Patient information,ultrasound findings,semen analysis,hormone profiles,and treatment information were collected,and the clinical outcomes were evaluated.Of 33 patients,29 patients were retrospectively analyzed.Vasoepididymostomy(VE)or cross VE was performed in 12 patients,the patency rate was 41.7%(5/12),and natural pregnancy was achieved in one of the patients.The other 17 patients underwent testicular sperm extraction as the distal vas deferens(contralateral side)was obstructed.These findings showed that VE or cross VE remains an alternative treatment for CUAVD patients with OA,even with a relatively low rate of patency and natural pregnancy.