Acute BRCAness Induction and AR Signaling Blockage through CDK12/7/9 Degradation Enhances PARP Inhibitor Sensitivity in Prostate Cancer.

Current treatments for advanced prostate cancer (PCa) primarily target androgen receptor (AR)-pathways. However, the emergence of castration-resistant prostate cancer (CRPC) and resistance to AR signaling inhibitors (ARSI) remains a significant clinical challenge. This study introduces BSJ-5-63, a novel triple degrader targeting cyclin-dependent kinases (CDKs) CDK12, CDK7, and CDK9, with potential to transform CRPC therapy. BSJ-5-63 effectively downregulates homologous recombination repair (HRR) genes, including BRCA1 and BRCA2, through CDK12 degradation, and attenuates AR signaling through CDK7 and CDK9 degradation, further enhancing its therapeutic impact. Importantly, BSJ-5-63 induces a "BRCAness" state that persists for a significant duration, enabling sequential combination therapy with PARP inhibitors (PARPis) while potentially minimizing drug-related toxicity and resistance. In both in vitro and in vivo studies, BSJ-5-63 exhibited potent antiproliferative effects in both AR-positive and AR-negative CRPC models. This study presents a promising multi-pronged approach for CRPC treatment, addressing both DNA repair mechanisms and AR signaling, with the potential to benefit a wide range of patients regardless of their BRCA1/2 mutational status. SIGNIFICANCE: This study introduces BSJ-5-63, a triple degrader designed to target CDK12, CDK7, and CDK9, making a significant advancement in CRPC therapy. The distinctive mechanism of BSJ-5-63 involves downregulating HRR genes and inhibiting AR signaling, thereby inducing a BRCAness state. This enhances sensitivity to PARP inhibition, effectively addressing ARSI resistance and improving the overall efficacy of treatment. The development of BSJ-5-63 represents a promising therapeutic approach, with the potential to benefit a broad spectrum of CRPC patients.

A carboxy-terminal ubiquitylation site regulates androgen receptor activity.

Degradation of unliganded androgen receptor (AR) in prostate cancer cells can be prevented by proteasome inhibition, but this is associated with only modest increases in polyubiquitylated AR. An inhibitor (VLX1570) of the deubiquitylases associated with the proteasome did not increase ubiquitylation of unliganded AR, indicating that AR is not targeted by these deubiquitylases. We then identified a series of AR ubiquitylation sites, including a not previously identified site at K911, as well as methylation sites and previously identified phosphorylation sites. Mutagenesis of K911 increases AR stability, chromatin binding, and transcriptional activity. We further found that K313, a previously reported ubiquitylation site, could also be methylated and acetylated. Mutagenesis of K313, in combination with K318, increases AR transcriptional activity, indicating that distinct posttranslational modifications at K313 differentially regulate AR activity. Together these studies expand the spectrum of AR posttranslational modifications, and indicate that the K911 site may regulate AR turnover on chromatin.

Simvastatin Enhances the Radiosensitivity of Androgen-independent Prostate Cancer Cells via Inhibition of RAD51 Expression.

BACKGROUND/AIM: Statins exert antitumor effects via various mechanisms. Additionally, the recurrence rate of prostate cancer after radiation therapy is lower in patients taking statins. This study investigated the efficacy of combination therapy with statins and irradiation in androgen-independent prostate cancer cells. MATERIALS AND METHODS: PC-3 and LNCaP human prostate cancer cell lines were used in this study. We developed androgen-independent LNCaP cells (LNCaP-LA) by gradually replacing fetal bovine serum (FBS) with charcoal-stripped FBS. Microarray analysis was performed, followed by Ingenuity Pathway Analysis. Cell viability was determined using the MTS assay. RESULTS: Simvastatin alters gene expressions in PC-3 cells. Microarray data showed that the number of differentially expressed genes was the highest in the pathway of "Role of BRCA1 in DNA Damage Response". In the validation, the expression of RAD51, listed in "Role of BRCA1 in DNA Damage Response", decreased significantly by simvastatin in PC-3 cells. Reduction in RAD51 expression following siRNA transfection increased the cytocidal effects of X-ray therapy in PC-3 and LNCaP-LA cells. The combination of simvastatin and irradiation further inhibited cell proliferation compared with monotherapy with either therapy in PC-3 or LNCaP-LA cells. In addition, compared with X-ray monotherapy, the combination of simvastatin and irradiation further enhanced the expression of γH2AX, which is reported to be one of the accurate markers of DNA damage in PC-3 cells. CONCLUSION: Simvastatin decreased the expression of RAD51 in androgen-independent prostate cancer cells. The combination of irradiation and drugs that reduce RAD51 expression can potentially affect androgen-independent prostate cancer growth.

Successful embolization of subcutaneous mesenteric varices within an ileal conduit in a patient with liver cirrhosis.

Introduction: Venous hemorrhage from ectopic varices is potentially fatal. This report describes a rare case in which bleeding from mesenteric varices in an ileal conduit was treated successfully by embolization therapy. Case presentation: The patient was an 82-year-old man who had previously undergone total pelvic exenteration for colon cancer with creation of an ileal conduit for urinary diversion. He subsequently developed liver cirrhosis and underwent partial hepatectomy for hepatocellular carcinoma. 9 years after his colon surgery, he was admitted with gross hematuria. Computed tomography revealed subcutaneous mesenteric varices in the ileal conduit and hemorrhage as a result of rupture of the varices. The bleeding continued despite repeated manual compression but was eventually stopped by embolization therapy. Conclusion: Embolization therapy may be helpful for hemostasis in the event of intractable bleeding from mesenteric varices in an ileal conduit.

Predictive models of long-term survival outcomes following radical cystectomy.

BACKGROUND: Identifying the likelihood of life-threatening recurrence after radical cystectomy by reliable and user-friendly predictive models remains an unmet need in the clinical management of invasive bladder cancer. METHODS: A total of 204 consecutive patients undergoing open radical cystectomy (ORC) for bladder cancer were retrospectively enrolled between May 2005 and August 2020. Clinicopathological and peri-ORC therapeutic data were extracted from clinical records. We explored predictive factors that significantly affected the primary endpoint of overall survival (OS) and secondary endpoints of cancer-specific survival (CSS) and recurrence-free survival (RFS). RESULTS: During a median follow-up of 3.9 years, 42 (20.6%) and 10 (4.9%) patients died due to bladder cancer and other causes, respectively. Five-year RFS, CSS, and OS were 66.5%, 77.6%, and 75.4%, respectively. Pathological T and N categories and lymphovascular invasion (LVI) significantly affected RFS by Cox regression analysis. Accordingly, clinical T and pathological N categories and LVI significantly affected CSS. Clinical T and pathological N categories, LVI, age, and ORC tumor grade significantly affected OS. Based on the assessment score for each independent risk factor, we developed the Gunma University Oncology Study Group (GUOSG) score, which predicts RFS, CSS, and OS. The GUOSG score classified four groups for RFS, three for CSS, and five for OS, with statistically significant distribution for nearly all comparisons. CONCLUSIONS: The GUOSG model is helpful to show individualized prognosis and functions as a risk-stratified historical cohort for assessing the lifelong efficacy of new salvage treatment regimens.

The utility of the [-2]pro-prostate-specific antigen level as a prognostic marker in patients with castration-resistant prostate cancer treated with enzalutamide.

BACKGROUND: The prostate health index (phi) derived using [-2]pro-prostate-specific antigen (p2PSA), a precursor of PSA, has been shown to predict cancer in the gray zone. However, the utility of p2PSA in predicting outcomes for castration-resistant prostate cancer (CRPC) patients remains unknown. Therefore, in this study, we aimed to evaluate the usefulness of p2PSA in predicting the efficacy and prognosis of enzalutamide treatment in CRPC patients. METHODS: We conducted a prospective study of CRPC patients treated with enzalutamide at our institution, measuring p2PSA levels in 98 pre-treatment serum samples. All patients were divided into two groups based on the median values of each parameter. The PSA progression-free survival (PSA-PFS) and overall survival (OS) were compared using the Kaplan-Meier method. This study was approved by the Institutional Review Board of Gunma University Hospital (IRB No. 2021-092, 1983). RESULTS: The median PSA level before enzalutamide treatment was 25.59 ng/mL, the median p2PSA level was 208.75 pg/mL, and the median phi was 187.95. PSA, p2PSA, and phi were not all predictors of PSA-PFS. However, the OS was significantly better in the low-value groups (log-rank p-values of PSA, p2PSA, and phi were 0.024, 0.034, and 0.018, respectively). In the docetaxel (DOC)-naive group (n = 58), PSA was not a predictor of OS, but p2PSA and phi were significantly associated with better OS in the low group. This relationship was not observed in the DOC-treated group. CONCLUSIONS: Our study elucidates the usefulness of p2PSA in predicting outcomes for CRPC patients treated with enzalutamide. It suggests that p2PSA and phi may be prognostic markers after enzalutamide administration in CRPC patients.

Retroperitoneal urothelial carcinoma arising after bladder diverticulectomy: a case report.

BACKGROUND: Urothelial carcinoma arises from the inner urothelial membrane of the renal pelvis, ureter, and bladder and often causes macrohematuria. Here, we report a rare case in which the patient developed non-symptomatic urothelial carcinoma anatomically outside the bladder wall 17 years after bladder diverticulectomy. CASE PRESENTATION: An 82-year-old male patient previously underwent gastrectomy for stomach cancer and partial hepatectomy for intrahepatic cholangiocarcinoma. Follow-up computed tomography revealed a tumor in the retroperitoneal space, where a bladder diverticulum was removed 17 years earlier. Multiparametric magnetic resonance imaging suggested that the tumor was malignant with rectal invasion. Subsequent computed tomography-guided percutaneous biopsy revealed that the tumor was urothelial carcinoma. The patient underwent two courses of neoadjuvant chemotherapy followed by pelvic exenteration with pelvic lymph node dissection. He is currently receiving adjuvant therapy with an immune checkpoint inhibitor and has had no recurrence for 3 months. CONCLUSIONS: Multiparametric magnetic resonance imaging is a helpful tool for predicting both tumor malignancy and invasion before a pathologically confirmed diagnosis. Although this case is rare, urologists should be aware of the occurrence of urothelial carcinoma after bladder diverticulectomy in cases of incomplete resection of the diverticulum.

A prospective study of the relationship between CRPC patient's quality of life after enzalutamide and serum testosterone levels measured via LC-MS/MS.

BACKGROUND: Enzalutamide (ENZ) is used in the treatment of patients with castration-resistant prostate cancer (CRPC). The quality of life (QoL) of CRPC patients during ENZ treatment is very important, but predictive markers of QoL have not been identified. We investigated the relationship between the serum testosterone (T) level before ENZ treatment and QoL changes in CRPC patients. PATIENTS AND METHODS: This prospective study was conducted between 2014 and 2018 at Gunma University Hospital and related facilities. We analyzed 95 patients in whom QoL could be evaluated using the Functional Assessment of Cancer Therapy-Prostate (FACT-P) questionnaire at baseline, and after 4 and 12 weeks of ENZ treatment. Serum T levels were measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS). RESULTS: The study population of 95 patients had a median age of 72 years and median prostate-specific antigen level of 21.6 ng/mL. The median overall survival from the commencement of ENZ treatment was 26.8 months. The median serum T level before ENZ treatment was 50.0 pg/mL. The mean total FACT-P scores at baseline, and after 4 and 12 weeks of ENZ treatment, were 95.8, 91.7, and 90.1, respectively. Differences in FACT-P scores between the high T level (High-T) group and low T level (Low-T) group (distinguished based on median split of the T level) were examined. The mean FACT-P scores were significantly higher in the High-T than Low-T group after both 4 and 12 weeks of ENZ treatment (98.5 vs. 84.6 and 96.4 vs. 82.2, respectively, both p < 0.05). The mean FACT-P score was significantly lower in the Low-T group after 12 weeks than before ENZ treatment (p < 0.05). CONCLUSION: The serum T level before treatment may be useful for predicting QoL changes after ENZ treatment in CRPC patients.

Two cases of CRPC with BRCA mutation treated by olaparib after favorable response to cisplatin.

Introduction: Several prostate cancers carry homologous recombination repair mutations that respond to olaparib. Because of the mechanism, the efficacy of platinum-based therapy can be used to predict the efficacy of poly(adenosine diphosphate-ribose) polymerase inhibitors such as olaparib. Case presentation: We experienced two neuroendocrine prostate cancer patients who achieved a response duration of more than 1 year with platinum-based therapy. Case 1 had a BRCA2 mutation in the germline and case 2 had a BRCA2 mutation in a somatic chromosome only. Both patients responded well to olaparib. Conclusion: Cisplatin and olaparib may overlap in response due to their medicinal action. It may be useful to consider genetic testing in some CRPC patients who have responded to cisplatin.

WNT5a Signaling through ROR2 Activates the Hippo Pathway to Suppress YAP1 Activity and Tumor Growth.

Noncanonical Wnt signaling by WNT5a has oncogenic and tumor suppressive activities, but downstream pathways mediating these specific effects remain to be fully established. In a subset of prostate cancer organoid culture and xenograft models, inhibition of Wnt synthesis stimulated growth, whereas WNT5a or a WNT5a mimetic peptide (Foxy5) markedly suppressed tumor growth. WNT5a caused a ROR2-dependent decrease in YAP1 activity, which was associated with increased phosphorylation of MST1/2, LATS1, MOB1, and YAP1, indicating Hippo pathway activation. Deletion of MST1/2 abrogated the WNT5a response. WNT5a similarly activated Hippo in ROR2-expressing melanoma cells, whereas WNT5a in ROR2-negative cells suppressed Hippo. This suppression was associated with increased inhibitory phosphorylation of NF2/Merlin that was not observed in ROR2-expressing cells. WNT5a also increased mRNA encoding Hippo pathway components including MST1 and MST2 and was positively correlated with these components in prostate cancer clinical datasets. Conversely, ROR2 and WNT5a expression was stimulated by YAP1, and correlated with increased YAP1 activity in clinical datasets, revealing a WNT5a/ROR2 negative feedback loop to modulate YAP1 activity. Together these findings identify Hippo pathway activation as a mechanism that mediates the tumor suppressive effects of WNT5a and indicate that expression of ROR2 may be a predictive biomarker for responsiveness to WNT5a-mimetic drugs. SIGNIFICANCE: WNT5a signaling through ROR2 activates the Hippo pathway to downregulate YAP1/TAZ activity and suppress tumor growth, identifying ROR2 as a potential biomarker to identify patients that could benefit from WNT5a-related agents.

Changes in Renal Function of Patients With Prostate Cancer: Focus on Androgen Deprivation Therapy.

BACKGROUND/AIM: To investigate the association between androgen deprivation therapy (ADT) and changes in the estimated glomerular filtration rate (eGFR) in male Japanese patients with prostate cancer, based on post-hoc analysis of data from a previous prospective study. PATIENTS AND METHODS: Among 103 patients with prostate cancer in whom renal function changes were tracked over 5 years, 88 were divided into a group who completed ADT within 3 years (short ADT group; n=47) and a group who continued with ADT for more than 5 years (continuous ADT group; n=41). We compared the groups in terms of the eGFR, calculated based on age and serum creatinine (mg/dl) before ADT initiation and every other year over the next 5 years. RESULTS: The eGFR decreased by 4.91 and 2.89 ml/min in the short and continuous ADT groups, respectively, over the 5-year period following ADT initiation. The respective decreases in the eGFR were 0.98 and 0.58 ml/min/year. No significant difference in the eGFR was observed between the two groups at any measurement point. Patients treated with ADT showed a decrease in the eGFR of 0.58-0.98 ml/min/year over a 5-year period, which is about twice as high as that of normal Japanese males. No significant difference in the eGFR by ADT duration was observed. CONCLUSION: The eGFR decreased by 0.58-0.98 ml/min/year in our ADT patients, which was about twice as high as the rate of decrease in normal Japanese males, and approximately the same as in urine protein-positive male patients. We suggest that a large decrease in the eGFR may not play a role in the development of acute kidney injury. In addition, the duration of ADT does not appear to have a significant effect on the eGFR.

Fibroblast growth factor receptor inhibitor erdafitinib promotes Mcl-1 degradation and synergistically induces apoptosis with Bcl-xL/Bcl-2 inhibitor in urothelial cancer cells.

Metastatic urothelial cancer is a lethal disease. Although recent advances in immunotherapies and targeted therapy against fibroblast growth factor receptor (FGFR)2/3 mutation (erdafitinib) have improved patient survival, there is still a critical need for novel therapeutic strategies for patients who do not benefit from these treatments. Evasion of apoptosis through amplifying anti-apoptotic Bcl-2 family proteins (Mcl-1, Bcl-xL, Bcl-2) is one mechanism responsible for treatment resistance in urothelial cancers, suggesting that targeting anti-apoptotic proteins may be a possible therapeutic strategy for urothelial cancers. Here, we showed that erdafitinib increased Mcl-1 degradation mainly through previously unknown mechanisms and synergized with a BH3 mimetic drug targeting Bcl-xL/Bcl-2 to induce apoptosis in FGFR wild-type urothelial cancer cells. Strikingly, clinical sequencing data showed amplification of MCL1 or BCL2L1 (encoding Bcl-xL) in subsets of FGFR mutation-negative bladder cancer tissues. In conclusion, these findings suggest that exploiting apoptosis pathways may be a promising treatment strategy for patients with FGFR wild-type metastatic urothelial cancer with Mcl-1 or Bcl-xL overexpression.

Variants in HOXB13, G132E and F127C, Are Associated With Prostate Cancer Risk in Japanese Men.

BACKGROUND/AIM: Several studies have reported on the relationship between HOXB13 variants and an increased prostate cancer (PC) risk. To our knowledge there are not many studies on HOXB13 mutations in Japanese patients with prostate cancer, and there many issues remain uninvestigated. We herein clarified the association between HOXB13 genetic variants and PC risk in a Japanese population. PATIENTS AND METHODS: PC patients were diagnosed at the Gunma University Hospital and affiliated hospitals from 1994 to 2016. Sanger sequencing was performed on the coding regions of the HOXB13 gene in 152 familial PC (FPC) patients. Genotyping was performed on single nucleotide variants (SNVs) found in Sanger sequencing in 230 FPC patients from 152 pedigrees and 197 sporadic PC (SPC) patients and 144 controls. Allelic frequency and clinical data for each variant were studied in cases and controls. RESULTS: G132E and F127C were identified in FPC patients. The frequencies of G132E and F127C were significantly higher compared to the control group (p=0.039). In three families, seven PC patients shared the G132E variant, within second-to-third-degree relatives. It was not possible to clarify to pathogenicity of each SNV alone. CONCLUSION: We found two significant variants of the HOXB13 gene, G132E, F127C by analyzing and comparing gene samples from PC and non-PC patients. Furthermore, the HOXB13 G132E variant was found significantly increased in the FPC group.

Autocrine Canonical Wnt Signaling Primes Noncanonical Signaling through ROR1 in Metastatic Castration-Resistant Prostate Cancer.

Wnt signaling driven by genomic alterations in genes including APC and CTNNB, which encodes ß-catenin, have been implicated in prostate cancer development and progression to metastatic castration-resistant prostate cancer (mCRPC). However, nongenomic drivers and downstream effectors of Wnt signaling in prostate cancer and the therapeutic potential of targeting this pathway in prostate cancer have not been fully established. Here we analyzed Wnt/ß-catenin signaling in prostate cancer and identified effectors distinct from those found in other tissues, including aryl hydrocarbon receptor and RUNX1, which are linked to stem cell maintenance, and ROR1, a noncanonical Wnt5a coreceptor. Wnt/ß-catenin signaling-mediated increases in ROR1 enhanced noncanonical responses to Wnt5a. Regarding upstream drivers, APC genomic loss, but not its epigenetic downregulation commonly observed in prostate cancer, was strongly associated with Wnt/ß-catenin pathway activation in clinical samples. Tumor cell upregulation of the Wnt transporter Wntless (WLS) was strongly associated with Wnt/ß-catenin pathway activity in primary prostate cancer but also associated with both canonical and noncanonical Wnt signaling in mCRPC. IHC confirmed tumor cell WLS expression in primary prostate cancer and mCRPC, and patient-derived prostate cancer xenografts expressing WLS were responsive to treatment with Wnt synthesis inhibitor ETC-1922159. These findings reveal that Wnt/ß-catenin signaling in prostate cancer drives stem cell maintenance and invasion and primes for noncanonical Wnt signaling through ROR1. They further show that autocrine Wnt production is a nongenomic driver of canonical and noncanonical Wnt signaling in prostate cancer, which can be targeted with Wnt synthesis inhibitors to suppress tumor growth. SIGNIFICANCE: This work provides fundamental insights into Wnt signaling and prostate cancer cell biology and indicates that a subset of prostate cancer driven by autocrine Wnt signaling is sensitive to Wnt synthesis inhibitors.

Combination therapy with novel androgen receptor antagonists and statin for castration-resistant prostate cancer.

BACKGROUND: One of the growth mechanisms of castration-resistant prostate cancer (CRPC) is de novo androgen synthesis from intracellular cholesterol, and statins may be able to inhibit this mechanism. In addition, statins have been reported to suppress the expression of androgen receptors (ARs) in prostate cancer cell lines. In this study, we investigated a combination therapy of novel AR antagonists and statin, simvastatin, for CRPC. METHODS: LNCaP, 22Rv1, and PC-3 human prostate cancer cell lines were used. We developed androgen-independent LNCaP cells (LNCaP-LA). Microarray analysis was performed, followed by pathway analysis, and mRNA and protein expression was evaluated by quantitative real-time polymerase chain reaction and Western blot analysis, respectively. Cell viability was determined by MTS assay and cell counts. All evaluations were performed on cells treated with simvastatin and with or without AR antagonists (enzalutamide, apalutamide, and darolutamide). RESULTS: The combination of darolutamide and simvastatin most significantly suppressed proliferation in LNCaP-LA and 22Rv1 cells. In a 22Rv1-derived mouse xenograft model, the combination of darolutamide and simvastatin enhanced the inhibition of cell proliferation. In LNCaP-LA cells, the combination of darolutamide and simvastatin led to reduction in the mRNA expression of the androgen-stimulated genes, KLK2 and PSA; however, this reduction in expression did not occur in 22Rv1 cells. The microarray data and pathway analyses showed that the number of differentially expressed genes in the darolutamide and simvastatin-treated 22Rv1 cells was the highest in the pathway termed "role of cell cycle." Consequently, we focused our efforts on the cell cycle regulator polo-like kinase 1 (PLK1), cyclin-dependent kinase 2 (CDK2), and cell cycle division 25C (CDC25C). In 22Rv1 cells, the combination of darolutamide and simvastatin suppressed the mRNA and protein expression of these three genes. In addition, in PC-3 cells (which lack AR expression), the combination of simvastatin and darolutamide enhanced the suppression of cell proliferation and expression of these genes. CONCLUSIONS: Simvastatin alters the expression of many genes involved in the cell cycle in CRPC cells. Thus, the combination of novel AR antagonists (darolutamide) and simvastatin can potentially affect CRPC growth through both androgen-dependent and androgen-independent mechanisms.

Androgen receptor and MYC equilibration centralizes on developmental super-enhancer.

Androgen receptor (AR) in prostate cancer (PCa) can drive transcriptional repression of multiple genes including MYC, and supraphysiological androgen is effective in some patients. Here, we show that this repression is independent of AR chromatin binding and driven by coactivator redistribution, and through chromatin conformation capture methods show disruption of the interaction between the MYC super-enhancer within the PCAT1 gene and the MYC promoter. Conversely, androgen deprivation in vitro and in vivo increases MYC expression. In parallel, global AR activity is suppressed by MYC overexpression, consistent with coactivator redistribution. These suppressive effects of AR and MYC are mitigated at shared AR/MYC binding sites, which also have markedly higher levels of H3K27 acetylation, indicating enrichment for functional enhancers. These findings demonstrate an intricate balance between AR and MYC, and indicate that increased MYC in response to androgen deprivation contributes to castration-resistant PCa, while decreased MYC may contribute to responses to supraphysiological androgen therapy.

Ratio of the expression levels of androgen receptor splice variant 7 to androgen receptor in castration refractory prostate cancer.

In clinical samples, the expression of androgen receptor (AR) and of AR splice variant 7 (AR-V7) is higher in castration-resistant prostate cancer (CRPC) compared with that in hormone-sensitive prostate cancer (PCa). However, there are only a few reports on the ratio of the expression levels of AR-V7 to AR (AR-V7/AR) in prostate tissue. The present study evaluated AR-V7/AR expression in various types of human prostate tissues and CRPC cells. Pretreatment prostate tissue samples from patients with benign prostatic hyperplasia (BPH; n=18), Gleason score 7 (n=17), and Gleason score 8-10 (n=26) were collected at the time of prostate biopsy, and tissue samples from CRPC patients (n=10) were collected at the time of transurethral resection of the prostate. Furthermore, androgen-independent LNCaP cells were established. The mRNA expression levels of AR and AR-V7, cell proliferation and prostate-specific antigen (PSA) production were evaluated by reverse transcription quantitative PCR, MTS assay and chemiluminescent enzyme immunoassay, respectively. There was a significant difference in AR-V7/AR expression ratios between the CRPC group and the BPH and pre-treatment PCa groups (CRPC, 7%; BPH and pre-treatment PCa, 1%). Subsequently, we compared the AR and AR-V7 expression levels in CRPC samples with those in the pretreatment prostate tissues from the same patients. The results demonstrated that the AR-V7/AR ratio increased from 3 to 9% after CRPC onset. Furthermore, in vitro experiment demonstrated that AR-V7 expression in LNCaP cells was increased after transforming into CRPC cells. The AR-V7/AR ratio also increased from 0.05 to 0.3%. In addition, small interfering (si)-RNA-mediated knockdown of AR inhibited the proliferation of and PSA production from androgen-independent LNCaP cells; however, AR-V7 knockdown had no effect. Conversely, siRNA-mediated knockdown of both AR and AR-V7 inhibited the proliferation of VCAP cells. In summary, the findings from the present study demonstrated that AR-V7 expression and AR-V7/AR ratio were increased after the onset of CRPC, which had a limited role in CRPC cell proliferation. Further investigation is required to clarify the roles of AR other splice variants and AR-V7 in CRPC.

Presepsin as a predictor of septic shock in patients with urinary tract infection.

BACKGROUND: Recently, presepsin has been reported to be a useful biomarker for early diagnosis of sepsis and evaluation of prognosis in septic patients. However, few reports have evaluated its usefulness in patients with urinary tract infections (UTI). This study aimed to evaluate whether presepsin could be a valuable marker for detecting severe sepsis, and whether it could predict the therapeutic course in patients with UTI compared with markers already used: procalcitonin (PCT) and C-reactive protein (CRP). METHODS: From April 2014 to December 2016, a total of 50 patients with urinary tract infections admitted to Gunma university hospital were enrolled in this study. Vital signs, presepsin, PCT, CRP, white blood cell (WBC) count, causative agents of urinary-tract infections, and other data were evaluated on the enrollment, third, and fifth days. The patients were divided into two groups: with (n = 11) or without (n = 39) septic shock on the enrollment day, and with (n = 7) or without (n = 43) sepsis on the fifth day, respectively. Presepsin was evaluated as a biomarker for systemic inflammatory response syndrome (SIRS) or septic shock. RESULTS: Regarding the enrollment day, there was no significant difference of presepsin between the SIRS and non-SIRS groups (p = 0.276). The median value of presepsin (pg/mL) was significantly higher in the septic shock group (p < 0.001). Multivariate logistic regression analysis showed that presepsin (≥ 500 pg/ml) was an independent risk factor for septic shock (p = 0.007). ROC curve for diagnosing septic shock indicated an area under the curve (AUC) of 0.881 for presepsin (vs. 0.690, 0.583, and 0.527 for PCT, CRP and WBC, respectively). Regarding the 5th day after admission, the median presepsin value on the enrollment day was significantly higher in the SIRS groups than in the non-SIRS groups (p = 0.006). On the other hand, PCT (≥ 2 ng/ml) on the enrollment day was an independent risk factor for SIRS. ROC curve for diagnosing sepsis on the fifth day indicated an AUC of 0.837 for PCT (vs. 0.817, 0.811, and 0.802 for presepsin, CRP, and WBC, respectively). CONCLUSIONS: This study showed that presepsin may be a good marker for diagnosing septic shock based on admission data in patients with UTI.

Metastatic Castration-Resistant Prostate Cancer Remains Dependent on Oncogenic Drivers Found in Primary Tumors.

Metastatic prostate cancer is initially sensitive to androgen receptor inhibition, but eventually becomes castration-resistant prostate cancer (mCRPC). Early use of more intensive therapies targeting androgen receptor and other oncogenic drivers in treatment-naïve primary prostate cancer (PC) may be more effective than that in advanced mCRPC. However, analysis of primary tumors may not reveal targetable metastatic drivers that are subclonal in the primary tumor or acquired at metastatic sites. METHODS: PC samples spanning one patient's clinical course: diagnostic biopsies, pre- or post-enzalutamide metastatic biopsies, and rapid autopsy samples including a patient-derived xenograft (PDX) were analyzed by targeted exome sequencing followed by phylogenetic analysis. RESULTS: Left- and right-lobe primary PC tumors appeared to diverge, with the right acquiring additional shared mutations and striking differences in copy number alterations that later appeared in metastatic samples during the treatment course and at autopsy, whereas the left base tumor maintained a quiet copy number alteration landscape and partitioned into a dead-end node. RB1 loss, a common finding in advanced castration-resistant disease, was identified throughout mCRPC samples, but not in the primary tumor. Significantly, a truncal EGFR-activating mutation (R108K) was identified in the primary tumor and was also found to be maintained in the mCRPC samples and in a PDX model. Furthermore, the PDX model remained sensitive to the EGFR inhibitor erlotinib, despite the presence of both RB1 and BRCA2 losses. CONCLUSION: These findings indicate that truncal alterations identified in primary PC can drive advanced mCRPC, even in the presence of additional strong oncogenic drivers (ie, RB1 and BRCA2 loss), and suggest that earlier detection and targeting of these truncal alterations may be effective at halting disease progression.