ASCL1 is activated downstream of the ROR2/CREB signaling pathway to support lineage plasticity in prostate cancer.

Lineage plasticity is a form of therapy-induced drug resistance. In prostate cancer, androgen receptor (AR) pathway inhibitors potentially lead to the accretion of tumor relapse with loss of AR signaling and a shift from a luminal state to an alternate program. However, the molecular and signaling mechanisms orchestrating the development of lineage plasticity under the pressure of AR-targeted therapies are not fully understood. Here, a survey of receptor tyrosine kinases (RTKs) identifies ROR2 as the top upregulated RTK following AR pathway inhibition, which feeds into lineage plasticity by promoting stem-cell-like and neuronal networks. Mechanistically, ROR2 activates the ERK/CREB signaling pathway to modulate the expression of the lineage commitment transcription factor ASCL1. Collectively, our findings nominate ROR2 as a potential therapeutic target to reverse the ENZ-induced plastic phenotype and potentially re-sensitize tumors to AR pathway inhibitors.

ASCL1 activates neuronal stem cell-like lineage programming through remodeling of the chromatin landscape in prostate cancer.

Treatment with androgen receptor pathway inhibitors (ARPIs) in prostate cancer leads to the emergence of resistant tumors characterized by lineage plasticity and differentiation toward neuroendocrine lineage. Here, we find that ARPIs induce a rapid epigenetic alteration mediated by large-scale chromatin remodeling to support activation of stem/neuronal transcriptional programs. We identify the proneuronal transcription factor ASCL1 motif to be enriched in hyper-accessible regions. ASCL1 acts as a driver of the lineage plastic, neuronal transcriptional program to support treatment resistance and neuroendocrine phenotype. Targeting ASCL1 switches the neuroendocrine lineage back to the luminal epithelial state. This effect is modulated by disruption of the polycomb repressive complex-2 through UHRF1/AMPK axis and change the chromatin architecture in favor of luminal phenotype. Our study provides insights into the epigenetic alterations induced by ARPIs, governed by ASCL1, provides a proof of principle of targeting ASCL1 to reverse neuroendocrine phenotype, support luminal conversion and re-addiction to ARPIs.

An androgen receptor switch underlies lineage infidelity in treatment-resistant prostate cancer.

Cancers adapt to increasingly potent targeted therapies by reprogramming their phenotype. Here we investigated such a phenomenon in prostate cancer, in which tumours can escape epithelial lineage confinement and transition to a high-plasticity state as an adaptive response to potent androgen receptor (AR) antagonism. We found that AR activity can be maintained as tumours adopt alternative lineage identities, with changes in chromatin architecture guiding AR transcriptional rerouting. The epigenetic regulator enhancer of zeste homologue 2 (EZH2) co-occupies the reprogrammed AR cistrome to transcriptionally modulate stem cell and neuronal gene networks-granting privileges associated with both fates. This function of EZH2 was associated with T350 phosphorylation and establishment of a non-canonical polycomb subcomplex. Our study provides mechanistic insights into the plasticity of the lineage-infidelity state governed by AR reprogramming that enabled us to redirect cell fate by modulating EZH2 and AR, highlighting the clinical potential of reversing resistance phenotypes.

Functional inhibition of cancer stemness-related protein DPP4 rescues tyrosine kinase inhibitor resistance in renal cell carcinoma.

Tyrosine kinase inhibitors (TKIs) are used as targeted drugs for advanced renal cell carcinoma (RCC), although most cases eventually progress by acquiring resistance. Cancer stemness plays critical roles in tumor aggressiveness and therapeutic resistance, and dipeptidyl peptidase IV (DPP4) has been recently identified as a cancer stemness-related protein. A question arises whether DPP4 contributes to TKI efficacy in RCC. We established patient-derived RCC spheroids and showed that DPP4 expression is associated with stemness-related gene expression. TKI sunitinib resistance was rescued by DPP4 inhibition using sitagliptin or specific siRNAs in RCC cells and tumors. DPP4 expression can be inducible by retinoic acid and repressed by ALDH1A inhibition. Among type 2 diabetes patients with clinical RCC tumors, higher TKI efficacy is observed in those bearing DPP4high tumors treated with DPP4 inhibitors. This study provides new insights into TKI resistance and drug repositioning of DPP4 inhibitor as a promising strategy for advanced RCC.

HIF1α inhibitor 2-methoxyestradiol decreases NRN1 expression and represses in vivo and in vitro growth of patient-derived testicular germ cell tumor spheroids.

Testicular germ cell tumor (GCT) is the most common type of malignancy in young males. Patients with nonseminomatous GCT still have poor prognosis. To identify new therapeutic targets, we generated patient-derived cells (PDCs) and their xenograft (PDCX) models from 3 distinct GCT patients' specimens. The pathological features of GCT PDCs and PDCX tumors recapitulated those of nonseminomatous components exhibiting in the corresponding patients' specimens. Notably, stemness-related markers and hypoxia-related genes, including hypoxia inducible factor 1α (HIF1A) and neuritin 1 (NRN1), were abundantly expressed in three-dimensional spheroid cultures of GCT PDCs. We identified functional HIF1α response elements in the NRN1 promoter and defined that their transcriptional activities were substantially activated by hypoxia. HIF1α inhibition by siRNAs or an inhibitor, 2-methoxyestradiol, significantly suppressed NRN1 expression and decreased the in vitro and in vivo growth of PDC spheroids. Moreover, NRN1 knockdown efficiently suppressed PDC proliferation. These results suggest that HIF1α and NRN1 are potential diagnostic and therapeutic targets, and that 2-methoxyestradiol could be applied to clinical management of GCT. Overall, our GCT PDC and PDCX models would be useful as preclinical models for precision medicine targeting each patient.

ALDH1A1 in patient-derived bladder cancer spheroids activates retinoic acid signaling leading to TUBB3 overexpression and tumor progression.

Acquired chemoresistance is a critical issue for advanced bladder cancer patients during long-term treatment. Recent studies reveal that a fraction of tumor cells with enhanced tumor-initiating potential, or cancer stem-like cells (CSCs), may particularly contribute to acquired chemoresistance and recurrence. Thus, CSC characterization will be the first step towards understanding the mechanisms underlying advanced disease. Here we generated long-term patient-derived cancer cells (PDCs) from bladder cancer patient specimens in spheroid culture, which is favorable for CSC enrichment. Pathological features of bladder cancer PDCs and PDC-dependent patient-derived xenografts (PDXs) were basically similar to those of their corresponding patients' specimens. Notably, CSC marker aldehyde dehydrogenase 1A1 (ALDH1A1), a critical enzyme that synthesizes retinoic acid (RA), was abundantly expressed in PDCs. ALDH1A1 inhibitors and shRNAs repressed both PDC proliferation and spheroid formation, whereas all-trans RA could rescue ALDH1A1 shRNA-suppressed spheroid formation. ALDH inhibitor also reduced the in vivo growth of PDC-derived xenografts. ALDH1A1 knockdown study showed that tubulin beta III (TUBB3) was one of the downregulated genes in PDCs. We identified functional RA response elements in TUBB3 promoter, whose transcriptional activities were substantially activated by RA. Clinical survival database reveals that TUBB3 expression may associate with poor prognosis in bladder cancer patients. Moreover, TUBB3 knockdown was sufficient to suppress PDC proliferation and spheroid formation. Taken together, our results indicate that ALDH1A1 and its putative downstream target TUBB3 are overexpressed in bladder cancer, and those molecules could be applied to alternative diagnostic and therapeutic options for advanced disease.

Application of Prostate Cancer Models for Preclinical Study: Advantages and Limitations of Cell Lines, Patient-Derived Xenografts, and Three-Dimensional Culture of Patient-Derived Cells.

Various preclinical models have been developed to clarify the pathophysiology of prostate cancer (PCa). Traditional PCa cell lines from clinical metastatic lesions, as exemplified by DU-145, PC-3, and LNCaP cells, are useful tools to define mechanisms underlying tumorigenesis and drug resistance. Cell line-based experiments, however, have limitations for preclinical studies because those cells are basically adapted to 2-dimensional monolayer culture conditions, in which the majority of primary PCa cells cannot survive. Recent tissue engineering enables generation of PCa patient-derived xenografts (PDXs) from both primary and metastatic lesions. Compared with fresh PCa tissue transplantation in athymic mice, co-injection of PCa tissues with extracellular matrix in highly immunodeficient mice has remarkably improved the success rate of PDX generation. PDX models have advantages to appropriately recapitulate the molecular diversity, cellular heterogeneity, and histology of original patient tumors. In contrast to PDX models, patient-derived organoid and spheroid PCa models in 3-dimensional culture are more feasible tools for in vitro studies for retaining the characteristics of patient tumors. In this article, we review PCa preclinical model cell lines and their sublines, PDXs, and patient-derived organoid and spheroid models. These PCa models will be applied to the development of new strategies for cancer precision medicine.

Vasovasostomy and vasoepididymostomy: Review of the procedures, outcomes, and predictors of patency and pregnancy over the last decade.

BACKGROUND: In the era of improving assisted reproductive technology (ART), patients with obstructive azoospermia (OA) have 2 options: vasal repair or testicular sperm extraction with intracytoplasmic sperm injection. Vasal repair, including vasovasostomy (VV) and vasoepididymostomy (VE), is the only option that leads to natural conception. METHODS: This article reviews the surgical techniques, outcomes, and predictors of postoperative patency and pregnancy, with a focus on articles that have reported over the last 10 years, using PubMed database searches. MAIN FINDINGS: The reported mean patency rate was 87% and the mean pregnancy rate was 49% for a patient following microscopic VV and/or VE for vasectomy reversal. Recently, robot-assisted techniques were introduced and have achieved a high rate of success. The predictors and predictive models of postoperative patency and pregnancy also have been reported. The obstructive interval, presence of a granuloma, and intraoperative sperm findings predict postoperative patency. These factors also predict postoperative fertility. In addition, the female partner's age and the same female partner correlate with pregnancy after surgery. CONCLUSION: In the era of ART, the physician should present and discuss with both the patient with OA and his partner the most appropriate procedure to conceive by using these predictors.

Hypertension Cure Following Laparoscopic Adrenalectomy for Hyperaldosteronism is not Universal: Trends Over Two Decades.

BACKGROUND: Laparoscopic adrenalectomy has been established as a standard surgical method for unilateral primary aldosteronism. Meanwhile, the background characteristics of the patients undergoing adrenalectomy have changed over the last 20 years. The aim of this study was to investigate the changes in hypertension cure rates after laparoscopic adrenalectomy during the last two decades. METHODS: This retrospective clinical study included 176 patients who underwent unilateral laparoscopic adrenalectomy for primary aldosteronism from 1995 to 2015. The patients were divided into two groups by decade. The patients' baseline characteristics and the hypertension cure rates were compared between the two groups. Additionally, the values were re-examined based on predictive model predicting postoperative hypertension cure. RESULTS: The hypertension cure rate decreased significantly from 51.8 to 31.1%. The following variables were significantly different between the two groups: age, sex, body mass index, history of diabetes mellitus, preoperative systolic and diastolic blood pressures, potassium level, and plasma renin activity. CONCLUSIONS: This study showed that the number of patients with unfavorable conditions for hypertension cure after adrenalectomy has recently increased. The treatment goal for primary aldosteronism is not only to cure the hypertension but also to prevent organ disorders due to inappropriate aldosterone levels. Therefore, we recommend laparoscopic adrenalectomy for unilateral primary aldosteronism, even if hypertension is not always cured postoperatively. However, clinicians need to fully explain the postoperative hypertension outcomes to primary aldosteronism patients.

Composite pheochromocytoma with a malignant peripheral nerve sheath tumor: Case report and review of the literature.

Adrenal tumors with more than one cellular component are uncommon. Furthermore, an adrenal tumor composed of a pheochromocytoma and a malignant peripheral nerve sheath tumor is extremely rare. A composite pheochromocytoma with malignant peripheral nerve sheath tumor in a 42-year-old man is reported here. After adequate preoperative control, left adrenalectomy was performed simultaneously with resection of the ipsilateral kidney for spontaneous rupture of the left adrenal tumor. Pathological findings demonstrated pheochromocytoma and malignant peripheral nerve sheath tumor in a ruptured adrenal tumor. To date, there have been only four reported cases of composite pheochromocytoma with malignant peripheral nerve sheath tumor, so the present case is only the fifth case in the world. Despite the very poor prognosis of patients with pheochromocytoma and malignant peripheral nerve sheath tumors reported in the literature, the patient remains well without evidence of recurrence or new metastatic lesions at 36 months postoperatively.

Testicular function among testicular cancer survivors treated with cisplatin-based chemotherapy.

Purpose: The aim of our study was to identify the clinical predictors of spermatogenesis recovery in testicular cancer (TC) patients after chemotherapy and to determine the recuperation period for spermatogenesis. Methods: Patients treated for TC from January 1982 to November 2001 at Chiba University Hospital were retrospectively assessed. Thirty-five patients who met the following criteria were examined-(i) underwent both high orchiectomy and cisplatin-based chemotherapy; (ii) had semen analyses and hormonal measurements; and (iii) were alive with no evidence of disease. Clinical variables associated with normalization of spermatogenesis after chemotherapy were examined. Time to recover normospermia was also evaluated using Kaplan-Meier analysis. Results: The observation period was 13.3 ± 5.6 years. Reappearance of sperm was confirmed in 85.7 % of patients, and 54.3 % of patients recovered normospermia. Age at diagnosis <25 years (p = 0.0057), number of chemotherapy cycles <4 cycles (p = 0.0042), and follicle-stimulating hormone at the end of chemotherapy <18 mIU/ml (p = 0.0220) were independent factors related to post-chemotherapy normalization of semen findings. The median (95 % CI) time to recover normospermia was 40 (range 22-96) months. Conclusions: These findings help to predict whether spermatogenesis will recover and its timing. They may also help clinicians identify and manage TC patients at a higher risk of prolonged azoospermia after chemotherapy.

Clinical predictors of prolonged postresection hypotension after laparoscopic adrenalectomy for pheochromocytoma.

BACKGROUND: Although the perioperative management of patients with pheochromocytoma has been improving recently, severe hypotensive episodes can occur that require postoperative catecholamine support and are challenging to manage. Our aim was to identify the clinical factors that predict prolonged postresection hypotension in patients after laparoscopic adrenalectomy for pheochromocytoma. METHODS: The records of 73 Japanese patients who underwent unilateral laparoscopic adrenalectomy for pheochromocytoma were surveyed retrospectively. Patients were divided into 2 groups according to whether catecholamine support was needed after postoperatively. Clinical and biochemical data were evaluated at baseline and after operation. RESULTS: Thirty-four of 73 patients (47%) required continuous infusion of catecholamine to maintain systolic blood pressure >90 mm Hg at the end of the operation. The median duration of postoperative catecholamine support was 17 hours (range, 3-130) in these 34 patients. On multivariate analysis, tumor size >60 mm, urinary epinephrine levels >200 µg/day, and urinary norepinephrine levels >600 µg/day were independent predictors of prolonged hypotension requiring postoperative catecholamine support. Tumor size and urinary norepinephrine levels were significantly correlated with the duration of postoperative catecholamine support. CONCLUSION: Larger tumor size and greater values of urinary epinephrine and norepinephrine levels were significant predictors of prolonged hypotension requiring postoperative catecholamine support. Moreover, tumor size and urinary norepinephrine levels were positively correlated with the duration of postoperative catecholamine support. Clinicians can identify and manage patients more effectively with a greater risk of prolonged hypotension after tumor resection using these preoperative clinical variables.

Prospective evaluation of the safety of transrectal ultrasound-guided transperineal prostate biopsy based on adverse events.

BACKGROUND: Although transperineal (TP) prostate biopsy is growing in popularity, its safety has not been evaluated based on extensive studies. We prospectively assessed the adverse events associated with transrectal ultrasound (TRUS)-guided TP 16-core prostate biopsy at a single institution. PATIENTS AND METHODS: We enrolled 2,086 males who underwent first-time TRUS-guided TP prostate biopsy under lumbar spinal anesthesia at Chiba Cancer Center between 2009 and 2013. Eight adverse events were assessed prospectively using a purpose-designed questionnaire. The prevalence and duration of all adverse events were evaluated. We performed subgroup analyses for hematuria and urinary retention in relation to clinical factors. RESULTS: Questionnaires were collected from 1,663 cases (79.7 %). The cancer detection rate was 53.5 % in all patients. The prevalence and duration of complications were as follows: hematuria, 73.4 % and 4.51 ± 2.88 days; perineal bleeding, 7.1 % and 2.20 ± 2.24 days; hematospermia 14.4 %; dysuria, 15.7 % and 3.12 ± 2.71 days; urinary tract pain, 49.5 % and 2.43 ± 2.08 days; perineal pain, 35.5 % and 3.53 ± 2.59 days; fever ≥37 °C, 1.7 % and 1.79 ± 1.72 days; and headache, 22.1 % and 3.40 ± 2.10 days. Seventeen patients (1.1 %) required indwelling urethral catheterization for grade 2 urinary retention. Pre-biopsy International Prostate Symptom Score (p = 0.014) was an independent related factor for hematuria. Prostate volume (p = 0.001) was an independent related factor for grade 2 urinary retention. CONCLUSIONS: TRUS-guided TP prostate biopsy under lumbar spinal anesthesia can be performed safely with only minor adverse events.

Therapeutic outcomes of neoadjuvant and concurrent androgen-deprivation therapy and intensity-modulated radiation therapy with gold marker implantation for intermediate-risk and high-risk prostate cancer.

OBJECTIVES: To investigate the therapeutic outcomes of neoadjuvant and concurrent androgen-deprivation therapy and intensity-modulated radiation therapy with gold marker implantation for intermediate- and high-risk prostate cancer. METHODS: This was a retrospective study of 325 patients with intermediate- or high-risk prostate cancer according to the National Comprehensive Cancer Network guidelines who underwent androgen-deprivation therapy and intensity-modulated radiation therapy (76 Gy) after gold marker implantation between 2001 and 2010. RESULTS: The 5-year distant metastasis-free survival rate was significantly lower for very high-risk patients than for intermediate- and high-risk patients (82.6% vs 99.4% and 96.5%, respectively; P < 0.01). The 5-year biochemical relapse-free survival rates significantly declined with increasing prostate cancer risk (P < 0.01), and were 95.9%, 87.2%, and 73.1% for the intermediate-risk, high-risk and very high-risk patients, respectively. Acute genitourinary and gastrointestinal toxicity grade ≥3 were not observed in any of the patients. Late grade 3 genitourinary toxicity occurred in 0.3% of patients. CONCLUSION: Combination androgen-deprivation therapy and 76-Gy intensity-modulated radiation therapy with gold marker implantation offers good therapeutic outcomes with few serious complications in patients with intermediate- and high-risk prostate cancer.

Efficacy of traditional and alternative sunitinib treatment schedules in Japanese patients with metastatic renal cell carcinoma.

We report the adverse events and efficacy of traditional (4 weeks on 2 weeks off) and alternative sunitinib treatment schedules for Japanese patients with metastatic renal cell carcinoma. We retrospectively investigated 54 patients who received sunitinib for metastatic renal cell carcinoma between May 2006 and June 2012: 32 received a traditional treatment schedule and 22 received an alternative schedule. According to the Memorial Sloan-Kettering Cancer Center risk classification, five patients had favorable prognoses, 42 had intermediate prognoses and seven had poor prognoses. The mean observation periods were 16.3 and 20 months for the traditional and alternative schedule groups, respectively. Adverse events were significantly less common in the alternative schedule group, including most high-grade events. In the traditional and alternative schedule groups, median times to failure were 4.1 and 11.6 months (P = 0.040), median progression-free survival times were 4.1 and 11.3 months (P = 0.031), and median overall survival times were 12.0 and 32.1 months (P = 0.018), respectively. Each of these measures was better in the group of patients who received an alternative treatment schedule, suggesting that individualized changes to the sunitinib administration schedule can be effective.

Analysis of preoperative detection for apex prostate cancer by transrectal biopsy.

Background. The aim of this study was to determine concordance rates for prostatectomy specimens and transrectal needle biopsy samples in various areas of the prostate in order to assess diagnostic accuracy of the transrectal biopsy approach, especially for presurgical detection of cancer in the prostatic apex. Materials and Methods. From 2006 to 2011, 158 patients whose radical prostatectomy specimens had been evaluated were retrospectively enrolled in this study. Concordance rates for histopathology results of prostatectomy specimens and needle biopsy samples were evaluated in 8 prostatic sections (apex, middle, base, and transitional zones bilaterally) from 73 patients diagnosed at this institution, besides factors for detecting apex cancer in total 118 true positive and false negative apex cancers. Results. Prostate cancer was found most frequently (85%) in the apex of all patients. Of 584 histopathology sections, 153 (49%) from all areas were false negatives, as were 45% of apex biopsy samples. No readily available preoperative factors for detecting apex cancer were identified. Conclusions. In Japanese patients, the most frequent location of prostate cancer is in the apex. There is a high false negative rate for transrectal biopsy samples. To improve the detection rate, transperitoneal biopsy or more accurate imaging technology is needed.