Enzalutamide versus Abiraterone Plus Prednisolone for Nonmetastatic Castration-Resistant Prostate Cancer: A Sub-Analysis from the ENABLE Study for PCa

Enzalutamide (ENZ) and abiraterone plus prednisolone (ABI) can improve the survival of patients with castration-resistant prostate cancer (CRPC). However, the agent that is more effective against nonmetastatic CRPC remains unclear. To evaluate the agent that can be used as the first-line treatment for CRPC, an investigator-initiated, multicenter, randomized controlled trial (ENABLE Study for PCa) including both metastatic and nonmetastatic CRPC was conducted in Japan. The prostate-specific antigen (PSA) response rate, overall survival, some essential survival endpoints, and safety of patients with nonmetastatic CRPC were also analyzed. In this subanalysis, 15 and 26 patients in the ENZ and ABI arms, respectively, presented with nonmetastatic CRPC. There was no significant difference in terms of the PSA response rate between the ENZ and ABI arms (80% and 64%, respectively; p = 0.3048). The overall survival did not significantly differ between the two arms (HR: 0.68; 95% CI: 0.22-2.14, p = 0.5260). No significant differences were observed in terms of radiographic progression-free survival and cancer-specific survival between the ENZ and ABI arms (HR: 0.81; 95% CI: 0.35-1.84; p = 0.6056 and HR: 0.72; 95% CI: 0.19-2.73; p = 0.6443, respectively). Only four and six patients in the ENZ and ABI arms, respectively, had ≥grade 3 adverse events. ABI and ENZ had similar efficacy and safety profiles in patients with nonmetastatic CRPC.

[Idiopathic Thrombocytopenia Purpura After Pembrolizumab Treatment Against Locally Recurrent Bladder Cancer : A Case Report]

A man in his 70s visited our hospital for gross hematuria. He was diagnosed with invasive urothelial carcinoma (cT3N2M0) and underwent total cystectomy and ileum conduit construction after three courses of neoadjuvant chemotherapy. Eight months after the operation, the disease reoccurred in the pelvic lesion. He received pembrolizumab therapy but developed idiopathic thrombocytopenic purpura (ITP) immediately before the ninth course of administration; and, treatment was discontinued. Recovery of symptoms and normalization of blood test data were achieved 3.5months after starting steroid treatment. Reduction of recurrent disease has been maintained for 2 years.

Mixed epithelial and stromal tumor of the kidney with long-term imaging follow-up

Mixed epithelial and stromal tumor (MEST) of the kidney is a rare benign tumor with malignant potential, and is characterized by epithelial and stromal proliferation with a variety of cellularity and growth pattern. MEST of the kidney is often depicted as a well-defined, solid mass with a cystic component. However, due to the rarity of the disease, there are no reports of its progression in serial imaging examinations. This report presents the case of a 68-year-old woman with MEST who was followed for 13 years by computed tomography (CT). To the best of our knowledge, this is the first report of image findings of MEST of the kidney over a follow-up period longer than 10 years.

Impact of family history on clinicopathological variables and disease progression in Japanese prostate cancer patients undergoing robotic-assisted radical prostatectomy

OBJECTIVE

We evaluated whether a first-degree family history (FH) of prostate cancer (PCa) in Japanese patients undergoing robotic-assisted radical prostatectomy (RP) is correlated with clinicopathological variables and disease progression.

METHODS

We reviewed consecutive 392 localized PCa patients undergoing robotic-assisted RP at our institution between 2015 and 2020. Information on FH was obtained via a self-administered questionnaire. A positive FH was defined as having a first-degree FH: a father and/or one or more brothers with PCa prior to diagnosis. All patients had clinically localized PCa treated by robotic-assisted RP. We evaluated the relationship between clinical characteristics, pathological findings, and biochemical progression-free survival (bPFS) according to first-degree FH status.

RESULTS

Median follow-up was 20.8 months. FH was identified in 42 (10.7%) patients. Patients in the FH group (median, 64.8 years) were diagnosed at a significantly younger age than patients in the non-FH (NFH) group (patients without FH) (median, 67.7 years) (p = 0.003). The 5-year bPFS in the FH and NFH groups was 72.0% and 78.1%, respectively (p = 0.90). A subgroup analysis revealed a significant difference in prostate-specific antigen (PSA) density between the FH group (median, 0.51 ng/ml/cm³ ) and the NFH group (median, 0.29 ng/ml/cm³ ) in patients younger than 60 years (p = 0.033).

CONCLUSIONS

In this RP population, FH of PCa was not associated with worse clinical characteristics, pathological findings, or disease progression. Patients with a FH underwent surgery at a significantly younger age, and among patients <60 years, patients with a FH had significantly higher PSA density compared with patients without a FH.

Succinate dehydrogenase B-deficient renal cell carcinoma with a germline variant in a Japanese patient: a case report

Succinate dehydrogenase (SDH)-deficient renal cell carcinoma (RCC) is a rare renal cancer. A 75-year-old Japanese female presented with gross hematuria. Computed tomography revealed two tumors in the left kidney, which were resected. Immunohistochemistry indicated negative staining for the B subunit of SDH (SDHB) in the resected specimen, leading to a final diagnosis of SDHB-deficient RCC. Genetic testing for SDHB showed a RCC germline variant in exon 6 (NM_003000.3:c.642 G > C) that was previously reported but associated with a novel phenotype (i.e., RCC). Twenty-six years prior, her daughter, who was 25 years old at the time, had undergone radical nephrectomy for a pathologic diagnosis of renal oncocytoma of the right kidney; SDHB immunostaining of her daughter's tumor was also negative retrospectively. We confirmed that her daughter carried the germline variant in SDHB exon 6, similar to the patient. The patient had no evidence of disease progression at 15 months after surgery.

Discontinuation of pembrolizumab for advanced urothelial carcinoma without disease progression: Nationwide cohort study

Pembrolizumab, an anti-programmed death 1 monoclonal antibody, has revolutionized the treatment of metastatic urothelial carcinoma. However, the optimal treatment duration for treatment responders has not been established. To address this, we retrospectively assess the treatment outcomes and duration of pembrolizumab for patients whose best response was complete response (CR) or partial response (PR) in a Japanese nationwide cohort of platinum-refractory metastatic urothelial carcinoma. Of 203 patients whose best response was CR or PR, 83 patients discontinued pembrolizumab before progression. The median pembrolizumab treatment duration was 6.9 months. The 2-year relapse-free survival (RFS), treatment-free survival, and OS rates after discontinuation were 49.0%, 57.4%, and 74.5%, respectively. CR, higher hemoglobin levels, and a better Eastern Cooperative Oncology Group performance status at the time of discontinuation were associated with significantly better RFS. Pembrolizumab was re-administered to 12 patients. Pembrolizumab re-challenge resulted in CR, PR, stable disease, and progressive disease in six, three, two, and one patient, respectively. Propensity score-matched landmark analysis revealed no significant OS difference between patients who continued or discontinued pembrolizumab at 6, 12, and 18 months (p = 0.91, 0.99, and 0.25, respectively). Our findings demonstrated that patients with objective responses had favorable survival outcomes and suggested that pembrolizumab could be discontinued safely in this population. This study should drive further efforts to optimize the treatment duration for pembrolizumab responders.

Enzalutamide versus abiraterone plus prednisolone before chemotherapy for Japanese castration-resistant prostate cancer patients: An investigator-initiated, multicenter, randomized controlled trial

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Background: Enzalutamide and abiraterone plus prednisolone demonstrated improvement of survival for castration-resistant prostate cancer (CRPC). However, it remains quite unclear which agent is better in terms of efficacy and safety for Asian patients. Methods: An investigator-initiated, multicenter, randomized controlled trial was conducted in Japan. CRPC patients before chemotherapy were randomly assigned to the enzalutamide or the abiraterone plus prednisolone arm (1:1). The primary endpoint is time to prostate-specific antigen (PSA) progression and secondary endpoints include PSA response rate (≥50% decline from baseline), overall survival, radiographic progression-free survival, and safety assessment. Results: Between February 20, 2015 and July 30, 2019, 203 patients were enrolled. After randomization, 92 in the enzalutamide and 92 in the abiraterone plus prednisolone arm were treated and analyzed. Time to PSA progression was not significantly different between arms (median 21.2 and 11.9 months in the enzalutamide and the abiraterone plus prednisolone arm, respectively; hazard ration 0.81, 95% CI 0.51-1.27, p = 0.1732). There was a significant difference in PSA response rate between arms (72% and 57% in the enzalutamide and the abiraterone plus prednisolone arm, respectively, p = 0.0425). There were no significant differences in overall and radiographic progression-free survival between arms (median 32.9 and 35.5months in the enzalutamide and the abiraterone plus prednisolone arm, respectively; hazard ration 1.17, 95% CI 0.72-1.88, p = 0.5290 and median 17.6 and 14.0 months in the enzalutamide and the abiraterone plus prednisolone arm, respectively; hazard ration 0.92, 95% CI 0.63-1.34, p = 0.6532). Grade ≥3 of adverse events were observed in 11% and 21% in the enzalutamide and the abiraterone plus prednisolone arm, respectively ( p = 0.1044). Conclusions: Enzalutamide did not show any survival benefits compared with abiraterone plus prednisolone but showed better PSA response rate with no significant differences of severe adverse event rate for Japanese CRPC patients. Our data suggest that antecedent use of enzalutamide to abiraterone plus prednisolone have potentially clinical benefits in Asian CRPC populations. Clinical trial information: UMIN000015529.

A case of adenocarcinoma of the rete testis with durable response to cisplatin-based chemotherapy

INTRODUCTION

Adenocarcinoma of the rete testis is a rare malignancy with a poor prognosis. We report a case of adenocarcinoma of the rete testis with a durable response to cisplatin-based chemotherapy.

CASE PRESENTATION

A 48-year-old man with Down syndrome (trisomy 21) presented with a 1-month history of painless swelling of the left scrotum. The physical examination revealed a left testis with a hydrocele associated with a tumor and enlarged pelvic and para-aortic lymph nodes. He underwent a radical orchiectomy. The specimen was diagnosed as adenocarcinoma of the rete testis. The patient received 7 cycles of chemotherapy (1 cycle of BEP and 6 cycles of EP) postoperatively. The metastatic lymph nodes were reduced in size for at least 12 months. Our patient with adenocarcinoma of the rete testis obtained an acceptable response to cisplatin-based chemotherapy.

CONCLUSION

We treated a patient with an adenocarcinoma of the rete testis who had an acceptable response to platinum-based chemotherapy.

Predictive urodynamic factors for de novo stress urinary incontinence after laparoscopic sacrocolpopexy for pelvic organ prolapse

OBJECTIVES

Laparoscopic sacrocolpopexy is often performed to treat pelvic organ prolapse. Preoperative stress urinary incontinence (SUI) can improve after laparoscopic sacrocolpopexy. In contrast, some patients without incontinence preoperatively develop SUI after pelvic organ prolapse repair (ie, de novo SUI). This study aimed to identify the preoperative predictive factors of de novo SUI after laparoscopic sacrocolpopexy.

METHODS

A total of 858 patients underwent laparoscopic sacrocolpopexy between January 2013 and November 2017 at Kameda Medical Center. Urodynamic studies were performed pre- and postoperatively on 75 patients. This retrospective study included 43 of 75 patients who did not have SUI preoperatively. We assessed urethral function according to functional profile length and maximum urethral closure pressure. We evaluated voiding function in terms of maximum flow rate, detrusor pressure at maximum flow rate, and postvoid residual volume. Furthermore, each factor was compared between de novo SUI-positive and SUI-negative groups.

RESULTS

After laparoscopic sacrocolpopexy, 30 (69.8%) patients presented with SUI. The preoperative maximum urethral closure pressure was significantly lower in the de novo SUI-positive group (36.0 cmH₂ O) than in the de novo SUI-negative group (50.5 cmH₂ O, P = .020). More patients with maximum urethral closure pressure <40 cmH₂ O had de novo SUI than patients with maximum urethral closure pressure ≥40 cmH₂ O (P = .004). There were no significant differences between preoperative maximum urethral closure pressure and postoperative maximum urethral closure pressure in either group.

CONCLUSIONS

Low preoperative maximum urethral closure pressure, particularly maximum urethral closure pressure <40 cmH₂ O, is a predictor of de novo SUI after laparoscopic sacrocolpopexy.

Pre-pembrolizumab neutrophil-to-lymphocyte ratio (NLR) predicts the efficacy of second-line pembrolizumab treatment in urothelial cancer regardless of the pre-chemo NLR

Neutrophil-to-lymphocyte ratio (NLR) was reported to be associated with prognosis of urothelial cancer (UC) patients receiving systemic chemotherapy or immunotherapy. However, it has not been elucidated how preceding first-line chemotherapy affects NLR and subsequent second-line pembrolizumab treatment. This multicenter study analyzed 458 patients with metastatic UC who received first-line chemotherapy and second-line pembrolizumab with regard to pre-chemotherapy and pre-pembrolizumab NLR in association with the efficacy of chemotherapy and pembrolizumab treatment. NLR was increased in 47% while decreased in 53% of patients before and after first-line chemotherapy. High pre-chemotherapy NLR (≥ 3) was significantly associated with unfavorable overall (OS, P = 0.0001) and progression-free (P < 0.0001) survivals after first-line chemotherapy. However, pre-chemotherapy NLR showed only modest influence on radiological response and survival after second-line pembrolizumab treatment, whereas pre-pembrolizumab NLR showed higher association. NLR decrease was associated with partial response or greater objective response by first-line chemotherapy, while NLR increase was associated with higher patient age. In conclusion, immediate pre-chemotherapy and pre-pembrolizumab NLR was significantly associated with efficacy of the following treatment, respectively. However, even patients with high pre-chemotherapy NLR achieved favorable OS if they had their NLR reduced by chemotherapy, whereas those with high pre-chemotherapy NLR yielded unfavorable OS if they had their NLR remained high after chemotherapy, suggesting that chemotherapy may have differential effect on the efficacy of subsequent pembrolizumab treatment in UC patients.

Efficacy and safety of pembrolizumab for older patients with chemoresistant urothelial carcinoma assessed using propensity score matching

BACKGROUND

We used real-world and large-scale data to assess the clinical efficacy and safety of pembrolizumab in older patients with advanced urothelial carcinoma (UC).

METHODS

A total of 608 patients who received pembrolizumab for the treatment of chemoresistant UC were retrospectively analyzed. All patients were histologically diagnosed with pure UC. Using propensity score matching (PSM) (ECOG performance status, site of metastasis, hemoglobin level and neutrophil-to-lymphocyte ratio, 1:1 matching), the overall survival (OS) and adverse events (AEs) of patients <75 and ≥75 years old were compared.

RESULTS

The median follow-up (IQR) period was 16.1 (9.9-20.5) months. After PSM, there were 215 patients each in the aged <75 years and aged ≥75-year-old groups. The median OS of all patients was estimated to be 10.4 months (95% confidence interval [CI] = 8.8-12.1). After PSM, the median OS was 7.8 months (95% CI = 5.2-10.4) in the <75-year-old group and 10.4 months (95% CI = 7.3-13.5) in the ≥75-year-old group (P = 0.186). Any-grade AEs were more frequently reported in the ≥75-year-old group in comparison to the age <75-year-old group (55.3% vs. 41.9%, P = 0.007), whereas there was no significant difference between the two groups in the incidence of grade ≥3 AEs (10.2% vs. 12.6%, P = 0.544). The objective response rate, defined as complete remission or a partial response, was 22.8% in the <75-year-old group and 25.1% in the ≥75-year-old group (P = 0.651).

CONCLUSIONS

The present study demonstrates that age does not affect the efficacy and safety of pembrolizumab treatment for advanced chemoresistant UC. Pembrolizumab treatment should not be avoided based on chronological age; however, close monitoring for the development of treatment-related AE should be considered for older patients.

Laparoscopic lateral suspension for pelvic organ prolapse in a case with difficulty in performing laparoscopic sacrocolpopexy

Introduction

Mesh fixation at the promontory is the most important procedure in laparoscopic sacrocolpopexy. We present a case of pelvic organ prolapse wherein sacrocolpopexy was converted to lateral suspension intraoperatively due to tissue weakness of the promontory.

Case presentation

A 66‐year‐old woman with a sensation of bulge in the vagina presented to our clinic. She was diagnosed with uterine prolapse (grade III). Laparoscopic sacrocolpopexy was planned; exposure of the promontory and mesh fixation at the vesicovaginal and rectovaginal space could be smoothly performed. However, handling the needle at the promontory was impossible due to tissue weakness of the anterior longitudinal ligament of the sacrum. Consequently, mesh fixation was converted to lateral suspension.

Conclusion

Difficult mesh fixation at the promontory is not rare in laparoscopic sacrocolpopexy. Lateral suspension may be useful as a trouble‐shooting procedure for laparoscopic sacrocolpopexy, and surgeons performing laparoscopic sacrocolpopexy should know this procedure.

Enzalutamide versus abiraterone as a first-line endocrine therapy for castration-resistant prostate cancer (ENABLE study for PCa): a study protocol for a multicenter randomized phase III trial

BACKGROUND

Both enzalutamide and abiraterone have demonstrated improved radiographic progression-free and overall survival for castration-resistant prostate cancer (CRPC) compared with placebo controls before docetaxel treatment in phase III studies. These oral agents target androgen and androgen receptor signaling and are thought to be less toxic than chemotherapy. Cross-resistance to these agents was recently reported because of their similar mechanism of action, and it is important to assess which agent is more effective to use initially for CRPC.

METHODS/DESIGN

The present study is a phase III, investigator-initiated, multicenter, head-to-head, randomized controlled trial investigating enzalutamide vs. abiraterone as a first-line treatment for CRPC patients. Patients will be randomly assigned to an enzalutamide or an abiraterone treatment group. The primary endpoint is the time to prostate-specific antigen progression. The target sample size is set at 100 patients per group (total, 200 patients). The study duration is 5 years, and the duration for recruitment is 2 years and 6 months.

DISCUSSION

Thus far, there have been no prospective head-to-head studies comparing enzalutamide and abiraterone. This ENABLE study will clarify which agent should be prioritized for CRPC patients and enable clinicians to decide the appropriate treatment before chemotherapy.

TRIAL REGISTRATION

University hospital Medical Information Network (UMIN) Center identifier UMIN000015529 . Registrated 11/1/2014.

[Urinary schistosomiasis: report of a case]

A 20-year-old unmarried Ghanaian man complaining of macroscopic hematuria and cystitis symptom was admitted to our institute. Abdominal ultrasound revealed a hyper echoic lesion in the entire bladder wall. Computed tomography showed a calcification of the whole bladder wall and of the left lower ureter. Flexible cystoscopy revealed many nodular masses, so-called 'bilharzial tubercles', at the trigone and posterior wall of the urinary bladder, and there was partial bleeding. Pathological examination revealed granuloma with many calcified eggs of schistosome haematobium. He was diagnosed with Bilharzial schistosomiasis and was treated with 1,500 mg of praziquantel for two days. However the therapeutic effect was insufficient. Therefore, he was treated with 2,400 mg of praziquantel for two days, and the symptoms disappeared.

[Effective dimethyl sulfoxide (DMSO) occlusive dressing technique for amyloidosis of the urinary bladder]

A 48-year-old married woman complaining of macroscopic hematuria and cystitis symptom was admitted to our institute. Flexible cystoscopy revealed many yellowish, nodular masses at the paries posterior of the urinary bladder, and cold-punch biopsy proved it to be amyloidosis. Serum amyloid protein A (SAA) was high, and suggested systemic amyloidosis. Renal biopsy and colon fiberscopy did not reveal any abnormalities. We therefore diagnosed a primary localized amyloidosis of the urinary bladder. Transurethral resection and dimethyl sulfoxide (DMSO) infusion therapy are used to treat amyloidosis of the urinary bladder. However there is no definite cure for amyloidosis of the urinary bladder. Therefore we selected DMSO occlusive dressing technique therapy. After 5 years of therapy, there was no evidence of a recurrence of amyloidosis.

[Clinical study of 62 patients with symptoms of male climacterium]

We prospectively reviewed the records of 62 patients who had sought evaluation at our hospital with a chief complaint of male climacteric symptoms. Late-onset hypogonadism (LOH)-related symptoms were evaluated during the initial visit based on the Aging Males' Symptoms (AMS) score, International Index of Erectile Function (IIEF) -5 score, and Center for Epidemiologic Studies Depression Scale (CES-D). Laboratory and endocrinologic testing, including the free testosterone (FT) level, was performed with blood samples collected before 10 : 00 am. The AMS psychological and CES-D scores in patients with a FT ＞8.5 pg/ml were significantly higher than those in patients with a FT ≦8.5 pg/ml. The study included 32 patients who were diagnosed with LOH (FT ≦8.5 pg/ml) and treated with androgen replacement therapy (ART). The total, somatic, psychological, and sexual scores of the AMS were significantly decreased after the third intramuscular administration of testosterone enanthate; there were no serious complications. Because a significant proportion of depressed patients may be amongst the patients with aging male's symptoms, it is important to consider depression in the exclusion diagnosis during a clinical examination for LOH.

[A case of primary malignant lymphoma of the prostate with characteristic MRI findings]

Here, we report a case of malignant lymphoma (ML) of the prostate. A 77-year-old man was referred to our hospital with the chief complaint of left lumbago. Computed tomography imaging showed a large mass below the bladder, as well as left hydronephrosis resulting from infiltration of the mass. Magnetic resonance imaging (MRI) revealed enlargement and high-intensity of the whole prostate with diffusionweighted image. An enlarged, stony, hard prostate was palpable on digital rectal examination, but the prostate-specific antigen (PSA) level was 4.65 ng/ml. Since the patient developed urinary retention and macrohematuria, transurethral hemostasis and biopsy were performed. Histological findings and immunohistochemical studies revealed diffuse large B-cell non-Hodgkin's lymphoma (DLBCL). MRI is thought to play a critical role in localization diagnosis of Non-Hodgkin's lymphoma (NHL) since NHL demonstrates characteristic signs. Although the frequency of primary ML of the prostate is low, by paying careful attention to the characteristic signs on MRI and examination findings, we should consider a differential diagnosis of ML of the prostate, which is not a typical manifestation of prostatic cancer.

Endocrine disrupter bisphenol A increases in situ estrogen production in the mouse urogenital sinus

The balance between androgens and estrogens is very important in the development of the prostate, and even small changes in estrogen levels, including those of estrogen-mimicking chemicals, can lead to serious changes. Bisphenol A (BPA), an endocrine-disrupting chemical, is a well-known, ubiquitous, estrogenic chemical. To investigate the effects of fetal exposure to low-dose BPA on the development of the prostate, we examined alterations of the in situ sex steroid hormonal environment in the mouse urogenital sinus (UGS). In the BPA-treated UGS, estradiol (E(2)) levels and CYP19A1 (cytochrome P450 aromatase) activity were significantly increased compared with those of the untreated and diethylstilbestrol (DES)-treated UGS. The mRNAs of steroidogenic enzymes, Cyp19a1 and Cyp11a1, and the sex-determining gene, Nr5a1, were up-regulated specifically in the BPA-treated group. The up-regulation of mRNAs was observed in the mesenchymal component of the UGS as well as in the cerebellum, heart, kidney, and ovary but not in the testis. The number of aromatase-expressing mesenchymal cells in the BPA-treated UGS was approximately twice that in the untreated and DES-treated UGS. The up-regulation of Esrrg mRNA was observed in organs for which mRNAs of steroidogenic enzymes were also up-regulated. We demonstrate here that fetal exposure to low-dose BPA has the unique action of increasing in situ E(2) levels and CYP19A1 (aromatase) activity in the mouse UGS. Our data suggest that BPA might interact with in situ steroidogenesis by altering tissue components, such as the accumulation of aromatase-expressing mesenchymal cells, in particular organs.

Effect of transforming growth factor α overexpression on urogenital organ development in mouse

Transforming growth factor-α (TGFα) promotes cell proliferation by binding to the epidermal growth factor receptor (EGFR). TGFα and EGFR overexpression have been reported in various human cancers. However, whether TGFα induces cancer by itself is unknown in urogenital organs. To investigate whether TGFα overexpression induces carcinogenesis in urogenital organs, we analyzed the phenotypes of urogenital organs in male TGFα transgenic (TG) mice of the CD1 strain. Urogenital organs including the kidney, bladder, prostate, seminal vesicles, testes, and epididymis were isolated from 4- to 48-week-old TGFα TG and wild-type (WT) CD1 mice. Prostates were separated into anterior prostate (AP), dorsolateral prostate (DLP), and ventral prostate (VP). Neither tumor formation nor epithelial hyperplasia was observed in the TGFα TG mouse urogenital organs that we have investigated. Histopathologically, in prostate, we found an increased number of p63-positive basal epithelial cells in the TGFα TG mice AP and DLP. There was no morphological change in the stromal component, such as hypercellular stroma or fibrosis. However, bladder weight was greater in TGFα TG mice than that in WT mice, and distended bladders were observed macroscopically in 19 of 20 TGFα TG mice over 20 weeks of age. Ki67 labeling index was increased significantly in the TGFα TG mouse urethral epithelium, whereas neither epithelial hyperplasia nor hypertrophy was observed. In conclusion, our results suggest that TGFα overexpression in mouse urogenital organs alone may not be responsible for tumor formation and epithelial hyperplasia, but is involved in bladder outlet obstruction.

Structural changes in alpha1-adrenoceptor antagonist-treated human prostatic stroma

Alpha1-adrenoceptor antagonists (alpha1-blockers) are currently used as first-line drugs for the treatment of benign prostatic hyperplasia (BPH). However, cases of BPH are often encountered in which the efficacy of alpha1-blockers decreases and switching to surgical treatment is required. One factor responsible for this resistance includes structural changes in prostatic tissue architecture following repeated oral administration of alpha1-blockers. Forty patients suspected of having prostate cancer, but without evidence of malignancy on prostatic biopsy were divided into two groups: an untreated group (n = 17) and an oral alpha1-blocker-treated group (n = 23). Twenty-one patients exhibiting resistance to oral alpha1-blocker therapy who underwent surgery were assigned into the surgically treated group. Each tissue sample was subjected to Masson's trichrome staining to distinguish collagen fibers from smooth muscle constituting prostatic stroma. The mean collagen fiber share was 62.2 +/- 10.4% in the untreated group, 72.1 +/- 9.1% in the oral alpha1-blocker-treated group, and 72.2 +/- 15.7% in the surgically treated group. Focusing on cases exhibiting high-collagen fiber share (70% or more), the distribution in each of the two alpha1-blocker-treated groups (16 of the 23 cases from the oral alpha1-blocker-treated group and 10 of the 21 cases from the surgically treated group) differed significantly from that in the untreated group (2 of the 17 cases). Our findings suggest that the accumulation of collagen fibers in prostatic stroma could be one of the factors responsible for alpha1-blocker treatment.

Evidence that androgen-independent stromal growth factor signals promote androgen-insensitive prostate cancer cell growth in vivo

Activation of tumor-stromal interactions is considered to play a critical role in the promotion of tumorigenesis. To discover new therapeutic targets for hormone-refractory prostate tumor growth under androgen ablation therapy, androgen-sensitive LNCaP cells and the derived sublines, E9 (androgen-low-sensitive), and AIDL (androgen-insensitive), were recombined with androgen-dependent embryonic rat urogenital sinus mesenchyme (UGM). Tumors of E9 + UGM and AIDL + UGM were approximately three times as large as those of LNCaP + UGM. Tumors grown in castrated hosts exhibited reduced growth as compared with those in intact hosts. However, in castrated hosts, E9 + UGM and AIDL + UGM tumors were still approximately twice as large as those of LNCaP + UGM. Cell proliferation in tumors of E9 + UGM and AIDL + UGM grown in castrated host, was significantly higher than that in tumors of LNCaP + UGM. In vitro, expression of fibroblast growth factor (FGF)-2 and IGF-I, but not FGF-7 mRNA, was significantly reduced in UGM under androgen starvation. In cell culture, E9 cells were responsive to FGF-2 and FGF-7 stimulation, while AIDL responded to FGF-7 and IGF-1. Expression of FGFR1 and FGFR2 was considerably higher in E9 than those in LNCaP, similarly expression of FGFR2 and IGF-IR were elevated in AIDL. These data suggest that activation of prostate cancer cell growth through growth factor receptor expression may result in the activity of otherwise androgen-independent stromal growth factor signals such as FGF-7 under conditions of androgen ablation.

A novel human tumor necrosis factor alfa mutein, F4614, inhibits in vitro and in vivo growth of murine and human hepatoma: implication for immunotherapy of human hepatocellular carcinoma

Although treatment for hepatocellular carcinoma (HCC) has recently improved, most patients still relapse and die from this disease. The development of new therapeutic and preventive strategies for HCC is, therefore, required. A novel mutant protein (mutein) of human tumor necrosis factor alfa (TNF-alpha mutein F4614, 1SSSRGDSD... 29V ... 155L) was developed to decrease several adverse effects of TNF-alpha. F4614 is known to lack hypotensive effects of human TNF-alpha without losing its anti-tumor effect in mice transplanted with Meth-A sarcoma. Our study investigated the anti-tumor effects of F4614 against hepatoma cells in vitro and in vivo. F4614 significantly inhibited growth of all four tumor cells in vitro. A murine hepatoma cell line, MH134, when incubated in the presence of F4614, exhibited upregulation of surface major histocompatibility complex (MHC) class-I, intercellular adhesion molecule-1 (ICAM-1) and B7-1 molecules, and a decreased proportion of cells in the G2/M phase of the cell cycle. In addition, F4614 induced apoptosis in a significant number of MH134 cells. TNF-alpha and F4614 (5 microg/mouse daily for 5 days) showed similar anti-tumor activities in syngeneic MH134-bearing mice and heterogeneic PLC/PRF/5-bearing athymic nude mice. Intratumoral injection of F4614 or TNF-alpha was more effective than intravenous injection. Immunohistochemical analysis of the tumors treated by F4614 revealed that tumors were surrounded with a large number of Mac-1+ cells and a small number of CD4+ and CD8+ T cells; that suggests that intratumoral injection of F4614 elicited host immunoreactions. Thus, F4614 may be a new strategy for immunotherapy of HCC.