Hiroyuki Tsunemori

Expression of autotaxin and acylglycerol kinase in prostate cancer : association with cancer development and progression

Lysophosphatidic acid (LPA) may enhance diverse biologic activities in prostate cancer. This study was conducted to analyze expression levels of LPA‐producing enzymes, autotaxin (ATX) and acylglycerol kinase (AGK), in prostate cancer with relevance to clinicopathological parameters. Real‐time RT‐PCR and western blotting were performed for ATX and AGK in non‐neoplastic prostate cells (PrECs and PrSCs) and prostate cancer cell‐lines (DU‐145, PC‐3, LNCaP, and AILNCaP). Immunohistochemical analyses were conducted in tissue specimens of 132 localized prostate cancer patients who underwent radical prostatectomy between 2001 and 2007 (median observation period, 22 months). Both enzymes were negatively expressed in PrECs and PrSCs at mRNA and protein levels. ATX expression was higher than AGK in AILNCaP, DU‐145, and PC‐3 cell‐lines, while AGK was mainly expressed in LNCaP cells. Immunohistochemically, ATX and AGK expressions were negative in non‐neoplastic epithelia, while both were weakly expressed in the majority of high‐grade intra‐epithelial neoplasia (HG‐PIN). In cancer foci, ATX and AGK expressions were strong in 49% and 62%, weak in 40% and 32%, and negative in 11% and 6%, respectively. Expressions of both enzymes were significantly correlated with primary Gleason grade of cancer foci (P < 0.0001) and capsular invasion (P = 0.03 and 0.003 respectively). ATX expression was significantly correlated with probability of prostate specific antigen (PSA)‐failure after surgery (P < 0.0001). In conclusion, LPA‐producing enzymes (ATX and AGK) were frequently expressed in prostate cancer cells and precancerous HG‐PIN. In particular, high expression levels of ATX were associated with both malignant potentials and poor outcomes. (Cancer Sci 2009; 100: 1631–1638)

Gene expression profiles of lysophosphatidic acid-related molecules in the prostate: relevance to prostate cancer and benign hyperplasia.

To elucidate gene expression profiles of lysophosphatidic acid (LPA)‐related molecules in cancer, pre‐cancerous lesion, and benign hyperplasia of the prostate.

Effect of the Phytotherapeutic Agent Eviprostat on Inflammatory Changes and Cytokine Production in a Rat Model of Nonbacterial Prostatitis

OBJECTIVES To examine the effect of the phytotherapeutic agent Eviprostat on the stromal-to-epithelial (S/E) ratio, level of macrophage infiltration, expression of the macrophage inhibitory cytokine-1 (Mic1) gene, and tumor necrosis factor-alpha (TNF-α) and interleukin-8 (IL-8) concentrations in prostate tissues in a rat model of nonbacterial prostatitis (NBP). MATERIALS AND METHODS Ten-month old Wistar rats were divided into 4 groups of 10: (1) NBP non-mixed feed (prostatitis control group); (2) NBP Eviprostat (0.1%) mixed feed (prostatitis Eviprostat group); (3) non-NBP non-mixed feed (nonprostatitis control group); and (4) non-NBP Eviprostat mixed-feed (nonprostatitis Eviprostat group). NBP was induced by castration followed by daily subcutaneous injection of 17β-estradiol for 30 days. Ventral prostate lobes were histopathologically examined with Massons trichrome staining or immunostaining with antimacrophage antibody. Mic1 mRNA levels were quantified by real-time reverse transcriptase polymerase chain reaction. Tissue concentrations of TNF-α and IL-8 were determined by enzyme-linked immunosorbent assay. RESULTS Stroma was the most abundant in prostatitis control rats. The mean S/E ratio in prostatitis Eviprostat rats was significantly lower than in prostatitis control rats (P < .0001). The high levels of macrophage infiltration found in prostatitis control rats were significantly reduced in prostatitis Eviprostat rats (P < .0001). The up-regulation of the Mic1 gene observed in prostatitis control rat prostates was significantly suppressed in prostatitis Eviprostat rats (P < .0001). A marked suppression of TNF-α and IL-8 secretion was also observed in prostatitis Eviprostat rats (P < .05). CONCLUSIONS Eviprostat significantly suppressed the S/E ratio, level of macrophage infiltration, Mic1 gene expression, and proinflammatory cytokines/chemokines in the prostate in a rat NBP model.

Effect of a phytotherapeutic agent, Eviprostat®, on prostatic and urinary cytokines/chemokines in a rat model of nonbacterial prostatitis.

Chronic inflammation in the prostate has recently been recognized as an important component of the symptom progression of benign prostatic hyperplasia. The objective of this study was to evaluate a range of cytokines/chemokines in prostate tissue and urine to identify markers of prostate inflammation in a prostatitis model and to investigate the effect of a phytotherapeutic agent, Eviprostat®, on these markers.

Health-related Quality of Life Evaluation in Patients Undergoing Cavernous Nerve Reconstruction During Radical Prostatectomy

OBJECTIVE Nerve-grafting surgery after resection of neuro-vascular bundles during radical prostatectomy is one of the promising resolutions for dilemma between cancer control and functional preservation. The objective of this study is to evaluate the effect of nerve-grafting surgery on health-related quality of life (HRQOL) in localized prostate cancer patients with special interest in the influence of sexual dysfunction on mental status. METHODS A total of 88 patients followed for a minimum of 12 months after surgery with a median follow-up of 48 months were enrolled in this study. Of those, 24 patients underwent unilateral nerve-sparing with contralateral nerve-grafting or bilateral nerve-grafting and 64 patients underwent prostatectomy without nerve-sparing procedure. HRQOL assessed with the Japanese version of Extended Prostate Cancer Index Composite (EPIC) and Medical Outcomes Study 8 Items Short Form Health Survey (SF-8) was analyzed cross-sectionally. RESULTS Patients in nerve-grafting group who recovered potency demonstrated higher sexual function scores compared with those without nerve-sparing procedure (P = 0.022 and 0.001 in 25-48 and 49 months or later, respectively). However, sexual bother scores in nerve-grafting group who recovered potency were lower than those without nerve-sparing procedure throughout the observation periods (P = 0.012 in 49 months or later). CONCLUSIONS Cavernous nerve reconstruction provided recovery of erectile dysfunction in substantial proportion of patients, which resulted in favorable physical HRQOL. Majority of these patients, however, did not seem to be satisfied with their sexual function, which caused sustained sexual bother feeling.

Case of vascular air embolism during holmium laser enucleation of the prostate.

Vascular air embolism is a rare complication during transurethral surgery. A case of air embolism during holmium laser enucleation of the prostate in a 76‐year‐old man is presented. During the step of morcellation, the patients blood pressure suddenly oscillated up and down, and end‐tidal CO2 and arterial saturation decreased. Transesophageal and transthoracic echocardiography showed air collection in the right atrium. It was also discovered that incorrect assembly of the tube from the morcellator caused rapid entrainment of air into the vein. Computed tomography and abdominal X‐ray showed niveau formation in the femoral vein and air collection in the pelvic retroperitoneal space. The patient recovered with careful observation and was discharged 7 days after the operation with no sequelae. This report is presented to remind urologists of this unusual complication that can occur during holmium laser enucleation of the prostate procedures.

The Effect of Steep Trendelenburg Positioning on Retinal Structure and Function during Robotic-Assisted Laparoscopic Procedures

Purpose Robotic-assisted laparoscopic radical prostatectomy (RALP) has become a standard treatment choice for localized prostate cancer. RALP requires a steep Trendelenburg position, which leads to a significant increase in intraocular pressure (IOP). This study evaluated the effect on the retinal structure and function in patients undergoing RALP. Methods Standard automated perimetry (SAP) and optical coherence tomography (OCT) were performed in 20 males scheduled for RALP at 1 month and 1 day before the operation and at 1 and 3 months after the operation. IOP measurements were made in the supine position at 5 min after intubation under general anesthesia (T1), at 6 discrete time points (5, 30, 60, 120, 180, and 240 min; T2-7), and at 5 min after returning to a horizontal supine position (T8). Serial retinal nerve fiber layer (RNFL) thicknesses and visual field progression were assessed using the guided progression analysis software program. RNFL thickness progression and visual field progression were evaluated by event analysis. Results Average IOP (mmHg) for each time point was as follows: T1 = 12.3 ± 2.6, T2 = 20.4 ± 4.2, T3 = 23.3 ± 3.8, T4 = 24.0 ± 3.2, T5 = 24.3 ± 3.4, T6 = 27.1 ± 7.2, T7 = 29.8 ± 8.7, and T8 = 20.1 ± 4.4. During RALP, IOP significantly increased. There was no progression of the visual field and RNFL thickness after surgery or any other ocular complications found. Conclusions Although IOP significantly increased during RALP, there were no significant changes in the retinal structure and function between the pre- and postoperation observations.

Retroperitoneal liposarcoma excreting insulin‐like growth factor 2 that induced severe hypoglycemia

Insulin‐like growth factor 2 is overexpressed in various cancers, and is associated with a poor prognosis. Also, it is known that insulin‐like growth factor 2 is an etiology of non‐islet cell tumor hypoglycemia. In this report, we describe a case of unexpected hypoglycemia caused by a dedifferentiated liposarcoma producing insulin‐like growth factor 2. A large mass in the retroperitoneum was detected in a 61‐year‐old man who complained of appetite loss. Despite having no history of diabetes mellitus, hypoglycemia suddenly occurred after admission, but oral glucose therapy was ineffective. After total parenteral nutrition, tumor resection was attempted, but failed as a result of rigid adhesion to the surrounding organs. The patient died of the disease 21 days after surgery. Pathological diagnosis at autopsy revealed dedifferentiated liposarcoma, and immunohistochemical staining showed that the tumor excreted insulin‐like growth factor 2. The possibility of an insulin‐like growth factor 2‐producing tumor should be taken into consideration when we encounter a patient with spontaneous hypoglycemia resistant to glucose substitution therapy.

CLINICAL OUTCOMES OF EXTERNAL-BEAM RADIOTHERAPY COMBINED WITH NEOADJUVANT ANDROGEN DEPRIVATION THERAPY FOR HIGH-RISK PROSTATE CANCER

(Purpose) We investigated the outcome of external-beam radiotherapy (EBRT) with neoadjuvant androgen deprivation therapy (NeoADT) for high-risk prostate cancer defined by National Comprehensive Cancer Network (NCCN) guideline. (Patients and method) From 2002 to 2013, 70 patients with high-risk prostate cancer (PSA ≥20 ng/ml or clinical T stage ≥T3a, Gleason score ≥8) were treated with NeoADT and EBRT. EBRT consisted of three-dimensional conformal or intensity modulated radiotherapy with or without whole-pelvic radiation. Biochemical failure was defined according to the Phoenix definition. Biochemical progression-free survival (bPFS) and overall survival (OS) were calculated by Kaplan-Meier method, and prognostic factors for bPFS were analyzed by using the Cox proportional hazard model. (Result) The median age and initial prostate-specific antigen (PSA) level were 72 years old and 25.2 ng/ml, respectively. 43 patients had PSA level ≥20 ng/ml, 51 patients had clinical stage ≥T3a, 27 patients had Gleason score ≥8. The number of risk factors patients possessed was 1 (RiskN-1) in 31 patients, 2 (RiskN-2) in 27 patients and 3 (RiskN-3) in 12 patients. Median EBRT dose and duration of Neo ADT were 74 Gy and13.0 months, respectively. Whole-pelvic radiation was administered in 7 patients. After median follow-up of 4.8 years, biochemical and clinical failure occurred in 23 and 2 patients, respectively. No patients died of cancer. Five-year/8-year bPFS and OS were 63%/54% and 100%/91%, respectively. In multivariate analysis, three high-risk factor of NCCN guideline (PSA, clinical stage, Gleason score) did not predict outcome after EBRT independently, but RiskN (-1 vs -2, 3, HR 35.35, 95%CI 2.51-498.05, p<0.01) and pre-EBRT PSA (continuous, hazard ratio 1.31, 95%CI 1.01-1.71, p<0.05) were the significant predictors of bPFS. Five-year/8-year bPFS in RiskN-1 group and RiskN-2 or -3 group were 89%/79% and 47%/39%, respectively. Grade 3/4 adverse events (CTCAE ver4.0-JCOG) occurred in 2 patients. (Conclusion) Median dose of 74 Gy EBRT with intermediate-term NeoADT was safe and beneficial for high-risk prostate cancer. The number of risk factors and pre-EBRT PSA level were the independent prognostic factors for biochemical progression-free survival.

ELEVATED EXPRESSION OF LYSOPHOSPHOLIPASE D (AUTOTAXIN) AND ACYLGLYCEROL KINASE IN ONCOGENESIS AND PROGRESSION OF PROSTATE CANCER

INTRODUCTION AND OBJECTIVES: Prostate-specific membrane antigen (PSMA) provides an attractive target for monoclonal antibody (mAb) targeted therapies in the treatment of prostate cancer (PC). In this study, we generated an immunotoxin by linking a humanized anti-PSMA mAb (J591) to the ribosome-inactivating protein toxin saporin. The saporinJ591 immunoconjugate was evaluated for antitumor activity against PC cells. METHODS: PSMA-positive cell lines, LNCaP and CWR22Rv1 and a PSMA-negative cell line, PC-3, were used in these experiments. Humanized J591 was biotinylated and mixed in a 1:1 molar ratio with streptavidin-saporin (SAZAP). The binding ability of J591-saporin conjugate was compared to native, unconjugated J591 by enzymelinked immunosorbent assay and the extent of internalization into the cells was tested using immunofluorescence microscopy. The viability of cells treated with J591-SAZAP was examined by MTT assay and apoptotic cells were measured by flow cytometry 72 hours after J591saporin administration. RESULTS: The binding ability of J591-saporin to PSMA was equivalent to that of unconjugated J591. Internalization of J591-saporin was clearly detected in PSMA-positive, but not PSMA-negative, cell lines using fluoresceinisothiocyanateor Cy3-linked secondary antibodies (Fig. 1). The viability of LNCaP cells decreased to 20.16 ± 0.95% at a dose of 6.25 nM compared to the viability of PC-3 cells of 94.90 ± 4.84% at a dose of 100 nM (Fig. 2). In addition, after 72 hours of J591-SAZAP treatment, the percentage of apoptotic cells was 60.29% in LNCaP cells compared to 4.70% in PC-3 cells. CONCLUSIONS: Our findings show that humanized J591saporin conjugate has potent and selective antitumor effects on PSMApositive prostate cancer cells in vitro. This study supports development of conjugates of PSMA antibody to toxin proteins such as saporin for therapy of prostate cancer. Source of Funding: None