Mineralocorticoid receptor signaling inhibits bladder cancer progression.

The biological or clinical significance of mineralocorticoid receptor (MR) in urothelial cancer remains largely unknown. The present study aimed to determine the functional role of MR in bladder cancer progression. In two of the human bladder cancer lines expressing MR, treatment with a natural MR ligand, aldosterone, significantly reduced cell proliferation and migration, which was restored by three MR antagonists clinically used, spironolactone (except colony formation of androgen receptor-positive cells cultured in the presence of androgens), eplerenone, and esaxerenone. Similarly, MR knockdown via shRNA virus infection resulted in significant increases in cell viability/migration, as well as colony formation, compared with control sublines. In addition, MR knockdown augmented the expression of ß-catenin, c-fos, and N-cadherin, and lowered that of E-cadherin and p53, indicating the induction of the cadherin switching. Immunohistochemistry in surgical specimens detected MR signals in 58 (92.1%; 36.5% weakly-positive/1+, 44.4% moderately-positive/2+, and 11.1% strongly-positive/3+) of 63 muscle-invasive bladder cancers, which was significantly lower than in adjacent non-neoplastic urothelial tissues (100%; 15.7% 1+, 37.3% 2+, and 47.1% 3+). Moreover, patients with MR-high (3+) tumor had a significantly lower risk of cancer-specific mortality (P=0.039). Multivariable analysis further showed that strong MR expression was an independent predictor of cancer-specific survival in patients with muscle-invasive bladder cancer (hazard ratio 0.117, P=0.039). These findings suggest that MR signaling functions as a tumor suppressor in urothelial carcinoma and prevents tumor growth. Accordingly, there is a possibility that the concurrent use of anti-mineralocorticoids, particularly eplerenone and esaxerenone, in patients with bladder cancer rather contributes to the promotion of disease progression.

Intravenously engrafted human multilineage-differentiating stress-enduring (Muse) cells rescue erectile function after rat cavernous nerve injury.

OBJECTIVE: To evaluate the effect of intravenous administration of human multilineage-differentiating stress-enduring (Muse) cells on rat postoperative erectile dysfunction (ED) with cavernous nerve (CN) injury without an immunosuppressant. MATERIALS AND METHODS: Male Sprague-Dawley rats were randomised into three groups after CN crush injury. Either human-Muse cells, non-Muse mesenchymal stem cells (MSCs) (both 1.0 × 105 cells), or vehicle was infused intravenously at 3 h after CN injury without immunosuppressant. Erectile function was assessed by measuring intracavernous pressure (ICP) and arterial pressure (AP) during pelvic nerve electrostimulation 28 days after surgery. At 48 h and 28 days after intravenous infusion of Muse cells, the homing of Muse cells and non-Muse MSCs was evaluated in the major pelvic ganglion (MPG) after CN injury. In addition, expressions of C-X-C motif chemokine ligand (Cxcl12) and glial cell line-derived neurotrophic factor (Gdnf) in the MPG were examined by real-time polymerase chain reaction. Statistical analyses and comparisons among groups were performed using one-way analysis of variance followed by the Tukey test for parametric data and Kruskal-Wallis test followed by the Dunn-Bonferroni test for non-parametric data. RESULTS: The mean (SEM) ICP/AP values at 28 days were 0.51 (0.02) in the Muse cell group, 0.37 (0.03) in the non-Muse MSC group, and 0.36 (0.04) in the vehicle group, showing a significant positive response in the Muse cell group compared with the non-Muse and vehicle groups (P = 0.013 and P = 0.010, respectively). In the MPG, Muse cells were observed to be engrafted at 48 h and expressed Schwann cell markers S100 (~46%) and glial fibrillary acidic protein (~24%) at 28 days, while non-Muse MSCs were basically not engrafted at 48 h. Higher gene expression of Cxcl12 (P = 0.048) and Gdnf (P = 0.040) was found in the MPG of the Muse group than in the vehicle group 48 h after infusion. CONCLUSION: Intravenously engrafted human Muse cells recovered rat erectile function after CN injury in a rat model possibly by upregulating Cxcl12 and Gdnf.

Vitamin D Receptor Antagonist MeTC7 Inhibits PD-L1.

Small-molecule inhibitors of PD-L1 are postulated to control immune evasion in tumors similar to antibodies that target the PD-L1/PD-1 immune checkpoint axis. However, the identity of targetable PD-L1 inducers is required to develop small-molecule PD-L1 inhibitors. In this study, using chromatin immunoprecipitation (ChIP) assay and siRNA, we demonstrate that vitamin D/VDR regulates PD-L1 expression in acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS) cells. We have examined whether a VDR antagonist, MeTC7, can inhibit PD-L1. To ensure that MeTC7 inhibits VDR/PD-L1 without off-target effects, we examined competitive inhibition of VDR by MeTC7, utilizing ligand-dependent dimerization of VDR-RXR, RXR-RXR, and VDR-coactivators in a mammalian 2-hybrid (M2H) assay. MeTC7 inhibits VDR selectively, suppresses PD-L1 expression sparing PD-L2, and inhibits the cell viability, clonogenicity, and xenograft growth of AML cells. MeTC7 blocks AML/mesenchymal stem cells (MSCs) adhesion and increases the efferocytotic efficiency of THP-1 AML cells. Additionally, utilizing a syngeneic colorectal cancer model in which VDR/PD-L1 co-upregulation occurs in vivo under radiation therapy (RT), MeTC7 inhibits PD-L1 and enhances intra-tumoral CD8+T cells expressing lymphoid activation antigen-CD69. Taken together, MeTC7 is a promising small-molecule inhibitor of PD-L1 with clinical potential.

A case of testicular cancer with retroperitoneal lymph node metastasis of teratoma with somatic-type malignancy 18 years after initial treatment.

Introduction: In testicular cancer, late relapse of teratoma with somatic-type malignancy is rare and associated with a poor survival. A case of retroperitoneal lymph node metastasis of teratoma with somatic-type malignancy 18 years after initial treatment for testicular cancer is reported. Case presentation: A 46-year-old man had a 15-mm-sized mass in the para-aortic region 18 years after initial treatment for testicular cancer, without elevated serum alfa-fetoprotein or human chorionic gonadotropin levels. Laparoscopic retroperitoneal lymph node dissection was performed. The pathological findings showed teratoma with somatic-type malignancy, and the findings of primary testicular cancer reported a yolk sac tumor, not teratoma. Conclusion: Late relapse of teratoma with somatic-type malignancy was resected by laparoscopic retroperitoneal lymph node dissection. Therefore, long-term follow-up should be considered if patients with small retroperitoneal masses did not undergo retroperitoneal lymph node dissection, and early detection and surgical resection for relapse might be effective.

Association of second-hand smoke exposure, quantified by salivary cotinine, with dental caries in Japanese adolescents.

PURPOSE: Second-hand smoke has adverse effects on oral health. This cohort study used a multilevel approach to investigate the association of second-hand smoke exposure, as determined by salivary cotinine level, with dental caries in adolescents. METHODS: Data from 75 adolescents aged 11 or 12 years and 2,061 teeth without dental caries were analyzed in this study. Annual dental examinations to assess dental caries were conducted between 2018 and 2021. Salivary cotinine and Dentocult SM-Strip level were measured at baseline. Information on the smoking habits of parents, snack frequency, regular dental visits, and use of fluoride toothpaste was collected at baseline from parent-reported questionnaires. RESULTS: During the 3-year follow-up, dental caries was noted in 21 adolescents and 43 teeth. Participants exposed to parental smoking had higher salivary cotinine levels than those whose parents did not smoke. The multilevel Cox regression model showed that a high salivary cotinine level was associated with the incidence of dental caries, after adjusting for potential confounding factors (hazard ratio, 3.39; 95% confidence interval 1.08-10.69). CONCLUSION: This study suggests that the risk of dental caries is higher for adolescents who have high salivary cotinine levels attributable to second-hand smoke exposure.

Protective role of mineralocorticoid receptor signaling in urothelial tumorigenesis.

The expression status of mineralocorticoid receptor (MR) and its biological significance in human urothelial carcinoma remain unknown. The present study aimed to determine the functional role of MR in the development of urothelial cancer. In human normal urothelial SVHUC cells with exposure to a chemical carcinogen 3-methylcholanthrene (MCA), we assessed the effects of a natural MR ligand, aldosterone, and 3 MR antagonists, including spironolactone, eplerenone, and esaxerenone, as well as knockdown of MR via shRNA virus infection, on their neoplastic/malignant transformation. The in vitro system with carcinogen challenge showed that aldosterone and anti-mineralocorticoids significantly prevented and promoted, respectively, the neoplastic transformation of SVHUC cells. Similarly, MR knockdown in SVHUC cells considerably induced MCA-mediated neoplastic transformation, compared with a control subline. In addition, MR knockdown or antagonist treatment resulted in increases in the expression of ß-catenin, c-Fos, and N-cadherin, and a decrease in that of E-cadherin. Meanwhile, spironolactone, which is known to possess anti-androgenic activity, rather suppressed the neoplastic transformation of a SVHUC subline stably expressing wild-type androgen receptor, indicating its dominant effect via the androgen receptor pathway. Immunohistochemistry in surgical specimens detected MR signals in 77 (98.7%; 23.1% weak/1+, 42.3% moderate/2+, and 33.3% strong/3+) of 78 non-invasive bladder tumors, which was significantly (P<0.001) lower than in adjacent non-neoplastic urothelial tissues (100%; 20.5% 2+ and 79.5% 3+). Moreover, the risks for disease recurrence after transurethral surgery were marginally lower in female patients with MR-high (2+/3+) tumor (P=0.068) and significantly lower in all patients with MR-high/glucocorticoid receptor-high tumor (P=0.025), compared with respective controls. These findings suggest that MR signaling functions as a suppressor for urothelial tumorigenesis.

The Clinical Impact of Comedonecrosis Within Intraductal Carcinoma of the Prostate.

CONTEXT.­: Intraductal carcinoma of the prostate (IDC-P) is considered a distinct form of aggressive prostate cancer where comedonecrosis, a grade 5 pattern, is occasionally present. Meanwhile, assigning a Gleason grade to IDC-P remains controversial. OBJECTIVE.­: To assess the clinical significance of necrosis associated with IDC-P. DESIGN.­: We compared radical prostatectomy (RP) findings and oncologic outcomes in men with prostate cancer exhibiting IDC-P with (IDC-P+/N+) versus without (IDC-P+/N-) comedonecrosis. RESULTS.­: Of the 558 RPs examined, IDC-P was present in 213 cases (38.2%), including 167 (78.4%) with IDC-P+/N- and 46 (21.6%) with IDC-P+/N+. When comparing IDC-P+/N- versus IDC-P+/N+ cases, the presence of necrosis was significantly associated with higher tumor grade, higher incidence of pT3/pT3b or pN1 disease, and larger estimated tumor volume. Outcome analysis revealed a significantly higher risk of disease progression in IDC-P+/N+ patients than in IDC-P+/N- patients (P < .001). Significant differences in progression-free survival between IDC-P+/N- and IDC-P+/N+ patients were also seen in subgroups, such as those without (P = .01) or with (P = .03) adjuvant therapy immediately after RP, those with pN0 disease (P < .001), and, more interestingly, those exhibiting conventional Gleason pattern 5 component (P = .02). Multivariate analysis showed significance for IDC-P+/N+ when IDC-P (grade 4) and IDC-P+/N+ (grade 5) were (hazard ratio, 1.768; P = .049) or were not (hazard ratio, 2.000; P = .008) incorporated into the Gleason score. CONCLUSIONS.­: IDC-P+/N+ was found to be associated with worse histopathologic features on RP and poorer prognosis as an independent predictor. Pathologists may thus need to report the presence or absence of not only IDC-P but also comedonecrosis within IDC-P.

Clinical significance of perineural invasion by prostate cancer on magnetic resonance imaging-targeted biopsy.

Perineural invasion (PNI) by prostate cancer detected on systematic sextant biopsy (S-Bx) has been considered as a key prognosticator. However, the clinical significance of PNI on magnetic resonance imaging-targeted biopsy (T-Bx) needs to be further investigated. We assessed 169 patients undergoing T-Bx with concurrent S-Bx, followed by radical prostatectomy (RP) from 2015 to 2019. In all cases where cancer was detected on T-Bx only (n = 34) or both S-Bx and T-Bx (B-Bx; n = 135), PNI was found in 33 (19.5%) T-Bxs. Compared with no PNI, PNI on T-Bx was associated with higher Grade Group on biopsy/RP, higher pT stage, and lymph node metastasis. Outcome analysis revealed a significant difference in the risk of biochemical recurrence after RP between cases with and without PNI on T-Bx (P = 0.021). Next, in the 135 B-Bx cases, PNI was found on S-Bx only (n = 31), T-Bx only (n = 15), or B-Bx (n = 16). Compared with PNI on S-Bx, B-Bx PNI was associated with higher preoperative prostate-specific antigen, higher biopsy GG, higher pT stage, and larger tumor volume. There were no significant differences in any of the clinicopathologic features examined between cases with PNI on T-Bx only vs. B-Bx. Moreover, in this subgroup of patients, PNI on B-Bx was associated with significantly higher risks of biochemical recurrence, compared with PNI on S-Bx only (P = 0.024) or T-Bx only (P = 0.033). In multivariate analysis, PNI on B-Bx showed significance for recurrence (hazard ratio = 2.787, P = 0.034). The presence of PNI on T-Bx, particularly B-Bx, associated with worse histopathologic features on RP and poorer outcomes might thus be useful for risk stratification.

The Clinical Impact of pT3a Lesions in Patients With pT3b Prostate Cancer Undergoing Radical Prostatectomy.

CONTEXT.­: Seminal vesicle invasion (SVI) by prostate cancer (pT3b disease) has been considered as a key prognostic factor. OBJECTIVE.­: To assess the clinical impact of T3a lesions (ie, extraprostatic extension other than bladder neck invasion [BNI] or SVI [EPE], microscopic bladder neck invasion [mBNI]) in pT3b disease. DESIGN.­: We compared radical prostatectomy findings and long-term oncologic outcomes in 248 patients with pT3b disease, with versus without EPE/mBNI. RESULTS.­: Extraprostatic extension/mBNI was found in 219 (88.3%)/48 (19.4%) cases, respectively. Extraprostatic extension was significantly associated with higher preoperative prostate-specific antigen (PSA) level, higher rates of positive surgical margin (pSM) and lymphovascular invasion (LVI), and larger tumor volume. Similarly, mBNI was significantly associated with higher PSA level, higher rates of Grade Group(s) 4-5 or 5, pSM, LVI, and pN1, and larger tumor volume. Significant differences in all of these clinicopathologic features (except lymph node metastasis) between EPE-/mBNI+ or EPE+/mBNI- and EPE+/mBNI+ cases were also observed. Outcome analysis revealed that patients with EPE (P < .001) or mBNI (P < .001) had a significantly higher risk of disease progression than respective controls. Notably, there were significant differences in progression-free survival between EPE-/mBNI+ or EPE+/mBNI- cases and EPE-/mBNI- (P = .001) or EPE+/mBNI+ (P < .001) cases. In multivariate analysis, EPE (hazard ratio [HR] = 6.53, P = .009) and mBNI (HR = 2.33, P = .003), as well as EPE-/mBNI+ or EPE+/mBNI- (HR = 11.7, P = .01) and EPE+/mBNI+ (HR = 25.9, P = .002) versus EPE-/mBNI-, showed significance for progression. CONCLUSIONS.­: From these significant findings, we propose a novel pT3b subclassification: pT3b1 (SVI alone without EPE or mBNI), pT3b2 (SVI with either EPE or mBNI), and pT3b3 (SVI with both EPE and mBNI).

Androgen Receptor Signaling Induces Cisplatin Resistance via Down-Regulating GULP1 Expression in Bladder Cancer.

The underlying molecular mechanisms of resistance to cisplatin-based systemic chemotherapy in bladder cancer patients remain to be elucidated, while the link between androgen receptor (AR) activity and chemosensitivity in urothelial cancer has been implicated. Our DNA microarray analysis in control vs. AR knockdown bladder cancer lines identified GULP1 as a potential target of AR signaling. We herein determined the relationship between AR activity and GULP1 expression in bladder cancer cells and then assessed the functional role of GULP1 in cisplatin sensitivity. Androgen treatment in AR-positive cells or AR overexpression in AR-negative cells considerably reduced the levels of GULP1 expression. Chromatin immunoprecipitation further showed direct interaction of AR with the promoter region of GULP1. Meanwhile, GULP1 knockdown sublines were significantly more resistant to cisplatin treatment compared with respective controls. GULP1 knockdown also resulted in a significant decrease in apoptosis, as well as a significant increase in G2/M phases, when treated with cisplatin. In addition, GULP1 was immunoreactive in 74% of muscle-invasive bladder cancers from patients who had subsequently undergone neoadjuvant chemotherapy, including 53% of responders showing moderate (2+)/strong (3+) expression vs. 23% of non-responders showing 2+/3+ expression (P = 0.044). These findings indicate that GULP1 represents a key downstream effector of AR signaling in enhancing sensitivity to cisplatin treatment.

The Role of Estrogen Receptors in Urothelial Cancer.

Epidemiological data have indicated that there are some sex-related differences in bladder cancer. Indeed, the incidence of bladder cancer in men has been substantially higher than that in women throughout the world, while women tend to have higher stage disease and poorer prognosis. These gender disparities have prompted to investigate sex hormones and their cognitive receptors in bladder cancer. Specifically, estrogen receptors, including estrogen receptor-α and estrogen receptor-ß, have been shown to contribute to urothelial carcinogenesis and cancer progression, as well as to modulating chemosensitivity in bladder cancer, although conflicting findings exist. Meanwhile, immunohistochemical studies in surgical specimens have assessed the expression of estrogen receptors and related proteins as well as its associations with clinicopathologic features of bladder cancer and patient outcomes. This review article summarizes and discusses available data indicating that estrogen receptor signaling plays an important role in urothelial cancer.

Identification of BXDC2 as a Key Downstream Effector of the Androgen Receptor in Modulating Cisplatin Sensitivity in Bladder Cancer.

Underlying mechanisms for resistance to cisplatin-based chemotherapy in bladder cancer patients are largely unknown, although androgen receptor (AR) activity, as well as extracellular signal-regulated kinase (ERK) signaling, has been indicated to correlate with chemosensitivity. We also previously showed ERK activation by androgen treatment in AR-positive bladder cancer cells. Because our DNA microarray analysis in control vs. AR-knockdown bladder cancer lines identified BXDC2 as a potential downstream target of AR, we herein assessed its functional role in cisplatin sensitivity, using bladder cancer lines and surgical specimens. BXDC2 protein expression was considerably downregulated in AR-positive or cisplatin-resistant cells. BXDC2-knockdown sublines were significantly more resistant to cisplatin, compared with respective controls. Without cisplatin treatment, BXDC2-knockdown resulted in significant increases/decreases in cell proliferation/apoptosis, respectively. An ERK activator was also found to reduce BXDC2 expression. Immunohistochemistry showed downregulation of BXDC2 expression in tumor (vs. non-neoplastic urothelium), higher grade/stage tumor (vs. lower grade/stage), and AR-positive tumor (vs. AR-negative). Patients with BXDC2-positive/AR-negative muscle-invasive bladder cancer had a significantly lower risk of disease-specific mortality, compared to those with a BXDC2-negative/AR-positive tumor. Additionally, in those undergoing cisplatin-based chemotherapy, BXDC2 positivity alone (p = 0.083) or together with AR negativity (p = 0.047) was associated with favorable response. We identified BXDC2 as a key molecule in enhancing cisplatin sensitivity. AR-ERK activation may thus be associated with chemoresistance via downregulating BXDC2 expression in bladder cancer.

Impact of cancer therapy on post-treatment ejaculation disorder and sexual life in testicular cancer survivors.

OBJECTIVE: To evaluate the impact of cancer therapy on post-treatment ejaculation in patients with testicular cancer. METHODS: A total of 74 testicular cancer survivors provided completed International Index of Erectile Function-15 questionnaires before and after treatment between 2010 and 2017. Sexual function, particularly ejaculatory function, was evaluated before and after treatment. In this study, patients who answered "1 = almost never/never" or "2 = a few times" for questionnaire number 9 (ejaculation frequency) were defined as having "ejaculation disorder." RESULTS: Of 74 testicular cancer survivors, 50 (68%) had no ejaculation disorders before treatment. Four (44%) of nine survivors, who received chemotherapy and retroperitoneal lymph node dissection, developed ejaculation disorders after treatment. On multivariate analysis, retroperitoneal lymph node dissection was a significant predictor of post-treatment ejaculation disorder (P = 0.042). Of 60 survivors with evaluable ejaculation function after treatment, 24 (40%) did not attempt sexual intercourse, and multivariate analysis showed ejaculation disorder had a significant negative impact on having sexual intercourse (P = 0.035). Furthermore, the mean International Index of Erectile Function-15 scores in the groups with and without ejaculation disorders after treatment were 24.0 and 51.9, respectively (P < 0.001). CONCLUSION: Ejaculation disorders occur at high rate after retroperitoneal lymph node dissection. Many testicular cancer survivors reporting no sexual intercourse have ejaculation disorders, suggesting an adverse impact on sexual life. Urologists should provide proper counselling regarding the risk of ejaculation disorder and its possible impact on sexual life.

Trends in Age and Histology of Testicular Cancer from 1980-2019: A Single-Center Study.

Testicular cancer occurs in the testes of the male reproductive system and is the most common cancer in adolescent and young adult (AYA) men. However, recently, there have been more cases of testicular cancer in men older than 40 years. Therefore, trends of testicular cancer during the past 40 years were retrospectively examined, focusing on age and histology. Patients who were diagnosed with testicular cancer at our institution between 1980 and 2019 were enrolled in this study. The patients were divided into groups by the year of diagnosis (1980s, 1990s, 2000s, and 2010s), age at diagnosis (14, 15 to 39, and older than 40 years), and histological type (seminoma and non-seminoma). A total of 563 patients were diagnosed with testicular cancer over the 40-year period. The median age at diagnosis increased continuously, from 28 years to 31 years, 34 years, and 38 years in each period, respectively (p < 0.001). Moreover, most testicular cancer patients were of the AYA generation, whereas the ratio of patients older than 40 years increased significantly since 2000 (p < 0.001). The relative proportion of seminoma also increased more than 50% since 2000. In the seminoma group, median age increased from 31 years to 41 years during the 40-year period (p < 0.001). In conclusion, the age at diagnosis is rising for testicular cancer patients. Clinicians should recognize that testicular cancer affects not only the AYA generation, but there has been a shift to older than 40 years, especially in seminoma.

Estrogen receptor-ß signaling induces cisplatin resistance in bladder cancer.

The efficacy of cisplatin-based chemotherapy in patients with bladder cancer is often limited due to the development of therapeutic resistance. Our recent findings in bladder cancer suggested that activation of prostaglandin receptors (e.g. EP2, EP4) or cyclooxygenase (COX)-2 induced cisplatin resistance. Meanwhile, emerging evidence indicates the involvement of estrogen receptor-ß (ERß) signals in urothelial cancer progression. In this study, we aimed to investigate whether ERß activity was associated with cisplatin sensitivity in bladder cancer. Immunohistochemistry in muscle-invasive bladder cancer specimens from 55 patients who had subsequently received at least 3 cycles of cisplatin + gemcitabine neoadjuvant chemotherapy showed that ERß was positive in 38% of responders vs. 71% of non-responders (P = 0.016), including 42% of male responders vs. 65% of male non-responders (P = 0.142) and 20% of female responders vs. 100% of female non-responders (P = 0.048). Then, cisplatin cytotoxicity was compared in human bladder cancer cell lines. Control sublines endogenously expressing ERß were significantly more resistant to cisplatin treatment at its pharmacological concentrations, compared with ERß knockdown sublines via short hairpin RNA virus infection. An ER modulator tamoxifen increased sensitivity to cisplatin in ERα-negative/ERß-positive cell lines, while, in an estrogen-depleted condition, 17ß-estradiol reduced it. Additionally, western blot showed considerable elevation in ERß expression in cisplatin-resistant bladder cancer sublines, compared with respective controls. Moreover, treatment with tamoxifen or a COX-2 inhibitor celecoxib increased cisplatin sensitivity even in resistant cells, while COX-2/EP2/EP4 inhibitor treatment resulted in reduced expression of ERß. The expression and activity of ß-catenin known to involve cisplatin resistance was also up-regulated in cisplatin-resistant cells, which was further induced by 17ß-estradiol treatment. The present results suggest that estrogen-mediated ERß signaling plays an important role in modulating cisplatin sensitivity in bladder cancer cells. Targeting ERß during chemotherapy may thus be a useful strategy to overcome cisplatin resistance especially in female patients with ERß-positive bladder cancer.

FOXO1 inactivation induces cisplatin resistance in bladder cancer.

We found that FOXO1-shRNA sublines or FOXO1-positive cells co-treated with a FOXO1 inhibitor were significantly more resistant to cisplatin treatment at pharmacological concentrations, compared with respective control sublines or those with mock treatment. Western blot demonstrated considerable increases in the expression levels of a phosphorylated inactive form of FOXO1 (p-FOXO1) in cisplatin-resistant sublines established by long-term culture with low/increasing doses of cisplatin, compared with respective controls. Immunohistochemistry in surgical specimens from patients with muscle-invasive bladder cancer undergoing cisplatin-based neoadjuvant therapy further showed a strong trend to associate between p-FOXO1 positivity and unfavorable response to chemotherapy.

Compound A inhibits urothelial tumorigenesis via both the androgen receptor and glucocorticoid receptor signaling pathways.

Recent preclinical evidence has indicated that both androgen receptor (AR) inactivation and glucocorticoid receptor (GR) transrepression are associated with suppression of urothelial carcinogenesis. We therefore assessed the effect of a unique compound, 2-(4-acetoxyphenyl)-2-chloro-N-methylethylammonium chloride (Compound A; CpdA), which could function as an AR antagonist as well as a GR ligand, on urothelial tumorigenesis. Using the in vitro system with GR-positive non-neoplastic urothelial SVHUC cells stably expressing AR (SVHUC-AR), neoplastic transformation induced by a chemical carcinogen 3-methylcholanthrene (MCA) was inhibited similarly by an anti-androgen hydroxyflutamide and a glucocorticoid prednisone, and more strongly by CpdA. CpdA also prevented the neoplastic transformation of AR-negative MCA-SVHUC cells, which was diminished by a GR antagonist RU486, but failed to prevent that of GR knockdown MCA-SVHUC cells. In MCA-SVHUC-AR cells, CpdA significantly reduced the expression levels of oncogenes (c-Fos/c-Jun/c-Myc) and induced those of tumor suppressors (UGT1A/p21/p27/p53/PTEN). Additionally, a potent carcinogen N-butyl-N-(4-hydroxybutyl)nitrosamine induced bladder cancer in all of 8 mock-treated mice versus 4 (50%) of flutamide-treated (P = 0.021), 4 (50%) of prednisone-treated (P = 0.021), or 2 (25%) of CpdA-treated (P = 0.002) animals. Finally, CpdA was found to reduce AR transactivation and selectively induce GR transrepression (i.e. suppression of NF-κB transactivation and expression of its regulated genes), but not GR transactivation (i.e. activation of glucocorticoid-response element-mediated transcription and expression of its targets) in SVHUC cells. These findings suggest that CpdA suppresses urothelial tumorigenesis via both the AR and GR pathways, which may consequently provide an effective option of chemoprevention for bladder cancer, especially in patients with superficial disease following transurethral surgery.

FOXO1 as a tumor suppressor inactivated via AR/ERß signals in urothelial cells.

Androgen receptor (AR) and estrogen receptor-ß (ERß) have been implicated in urothelial tumor outgrowth as promoters, while underlying mechanisms remain poorly understood. Our transcription factor profiling previously performed identified FOXO1 as a potential downstream target of AR in bladder cancer cells. We here investigated the functional role of FOXO1 in the development and progression of urothelial cancer in relation to AR and ERß signals. In non-neoplastic urothelial SVHUC cells or bladder cancer lines, AR/ERß expression or dihydrotestosterone/estradiol treatment reduced the expression levels of FOXO1 gene and induced those of a phosphorylated inactive form of FOXO1 (p-FOXO1). In chemical carcinogen-induced models, FOXO1 knockdown via shRNA or inhibitor treatment resulted in considerable induction of the neoplastic transformation of urothelial cells or bladder cancer development in mice. Similarly, FOXO1 inhibition considerably induced the viability, migration, and invasion of bladder cancer cells. Importantly, in FOXO1 knockdown sublines, an anti-androgen hydroxyflutamide or an anti-estrogen tamoxifen did not significantly inhibit the neoplastic transformation of urothelial cells, while dihydrotestosterone or estradiol did not significantly promote the proliferation or migration of urothelial cancer cells. In addition, immunohistochemistry in surgical specimens showed that FOXO1 and p-FOXO1 expression was down-regulated and up-regulated, respectively, in bladder tumor tissues, which was further associated with worse patient outcomes. AR or ERß activation is thus found to correlate with inactivation of FOXO1 which appears to be their key downstream effector. Moreover, FOXO1, as a tumor suppressor, is likely inactivated in bladder cancer, which contributes in turn to inducing urothelial carcinogenesis and cancer growth.

Effects of α1-adrenergic receptor antagonists on the development and progression of urothelial cancer.

We recently demonstrated that silodosin, a selective α1-blocker often prescribed for the symptomatic treatment of benign prostatic hyperplasia (BPH), could inactivate a c-fos proto-oncogene regulator ELK1 in bladder cancer cells possessing a functional androgen receptor (AR). However, the clinical impact of α1-blockers on the development and progression of bladder cancer remained poorly understood. In the present study, we investigated if α1-blockers clinically used, including silodosin, tamsulosin, and naftopidil, could prevent the neoplastic/malignant transformation and cell growth, using non-neoplastic urothelial SVHUC sublines with carcinogen/MCA challenge and bladder cancer lines, respectively. Bladder cancers in men treated with silodosin, tamsulosin, or naftopidil for their BPH were then compared. Silodosin at 1-10 µM significantly inhibited the neoplastic transformation of MCA-SVHUC-AR cells, but not that of AR-negative MCA-SVHUC-control cells. In MCA-SVHUC-AR, silodosin significantly reduced the expression levels of oncogenes (c-fos/NF-κB1) and induced those of tumor suppressors (p27/PTEN). However, tamsulosin (up to 1 µM) or naftopidil (up to 10 µM) failed to significantly inhibit the neoplastic transformation of AR-positive or AR-negative urothelial cells. Similarly, cell proliferation/migration of AR-positive bladder cancer lines was considerably inhibited only by silodosin. Meanwhile, the incidence of bladder cancer in patients with silodosin [49/540 (9.1%)] was marginally lower, compared to those with tamsulosin [64/523 (12.2%); P=0.094] or tamsulosin or naftopidil [64+28/523+236 (12.1%); P=0.082]. There were no significant differences in tumor grade/stage among the 3 cohorts. Outcome analysis revealed lower risks for disease progression of non-muscle-invasive bladder tumors in the silodosin group than in the naftopidil group (P=0.011) or tamsulosin+naftopidil groups (P=0.035). Similarly, silodosin patients with muscle-invasive tumor had lower risks for disease progression, compared with tamsulosin (P=0.006) or tamsulosin+naftopidil (P=0.028) patients. Multivariate analysis further showed that silodosin treatment in those with non-muscle-invasive tumor was associated with improved progression-free survival, compared with naftopidil (hazard ratio=0.086; 95% confidence interval=0.008-0.905; P=0.041) or tamsulosin/naftopidil (hazard ratio=0.128; 95% confidence interval=0.016-1.036; P=0.054) treatment. Our in vitro studies thus indicate that both urothelial tumorigenesis and tumor growth are inhibited by silodosin, but not by tamsulosin or naftopidil. Clinical data further suggest that even pharmacological doses (e.g. 0.1 µM) of silodosin contribute to preventing bladder cancer progression.