Efficacy and safety of a newly developed polylactic acid microsphere as an injectable bulking agent for penile augmentation: 18-months follow-up.

Polylactic acid (PLA) fillers are widely used for cosmetic volume augmentation. But, no study has evaluated the use of PLA filler in penile augmentation (PA No. 4). We evaluated the efficacy and safety of a newly developed PLA filler for PA during a 18-month follow-up period. A total of 23 healthy adult men were prospectively enrolled between June and November 2012. Penile girth was measured at proximal-, mid- and distal-shaft at baseline, 3, 6, 12 and 18 months following injection. Subjects' satisfaction was assessed with visual analogue scale (VAS). Adverse events (AEs) were also reported. Mean injected volume was 20 ml. The circumference of proximal-, mid-, and distal-shaft increased by a mean of 2.2±0.2, 2.7±1.0 and 2.7±1.0 cm at 3 months, respectively (each P<0.001). No significant differences were noted in girth circumference between 3 and 18 months post-injection (each P>0.05). VAS score increased from 51.6±14.7 at baseline to 64.8±19.3 and 74.3±14.6 at 3 and 6 months, respectively (each P<0.05). Six cases of mild, transient treatment-emergent AEs were reported in 5 subjects. Serious AEs were not reported. In conclusion, penile injection of a newly developed PLA filler led to significant penile augmentative effects for up to 18 months and was well tolerated without serious AEs.

Effect of levitra on sustenance of erection (EROS): an open-label, prospective, multicenter, single-arm study to investigate erection duration measured by stopwatch with flexible dose vardenafil administered for 8 weeks in subjects with erectile dysfunction.

To investigate the change of erection duration measured by stopwatch with flexible dose vardenafil administered for 8 weeks in subjects with erectile dysfunction (ED). Effect of levitra on sustenance of erection was an open-label, prospective, multicenter and single-arm study designed to measure the duration of erection in men with ED receiving a flexible dose of vardenafil over an 8-week treatment period. Patients were instructed to take vardenafil 10 mg 60 min before attempting the intercourse. Vardenfil could be increased to 20 mg or decreased to 5 mg concerning patients' efficacy and safety. Following the initial screening, patients entered a 4-week treatment-free run-in phase and 8-week treatment period, during which they were instructed to attempt intercourse at least four times on four separate days. A total of 95 men were enrolled in 10 centers. After the 8 weeks treatment, the mean duration of erection leading to successful intercourse was statistically superior when patients were treated with vardenafil. After an 8-week treatment, the duration of erection leading to successful intercourse was 9.39 min. There were significant benefits with vardenafil in all domains of International Index of Erectile Function. Secondary efficacy end points included success rate of penetration, maintaining erection, ejaculation and satisfaction were superior when patients were treated with vardenafil. There was a significant correlation between duration of erection with other sexual factors. Also partner's sexual satisfaction was increased with vardenafil. Most adverse events were mild or moderate in severity. Vardenafil was safe and well tolerated. Vardenafil therapy provided a statistically superior duration of erection leading to successful intercourse in men with ED with female partner.

Comparison of the efficacy and safety of 5-mg once-daily versus 5-mg alternate-day tadalafil in men with erectile dysfunction and lower urinary tract symptoms.

The purpose of this study is to investigate and compare the effects of 5-mg once-daily tadalafil versus 5-mg alternate-day tadalafil in men with moderate-to-severe erectile dysfunction (ED) and lower urinary tract symptoms (LUTS). Between January 2012 and June 2013, 144 men presenting with an International Index of Erectile Function-5 (IIEF-5) score of <18 and an International Prostate Symptom Score (IPSS) of >8 were enrolled to the study. Patients were allocated the simple alternate randomization into Group I (5-mg once-daily tadalafil) and Group II (5-mg alternate-day tadalafil). Changes in IIEF scores, Sexual Encounter Profile Question 3 (SEP Q3) percentage, IPSS, uroflowmetry and post void residual at the first visit (V1), week 4 (V2) and week 12 (V3) were compared. No significant difference was found between the baseline patient characteristics of Group I and Group II. Treatment with 5-mg daily tadalafil demonstrated improvement in IIEF, SEP Q3 percentage and IPSS score between V1 and V2, and that between V1 and V3. Patients receiving 5-mg alternate-day tadalafil also showed a significant improvement in IIEF, SEP Q3 percentage, and IPSS score between V1 and V2, and that between V2 and V3. However, no significant improvements were found in any other parameters. There were no significant differences between Group I and Group II apart from IIEF scores in V2 (19.4 versus 17.9, respectively). The SEP Q3 percentage was also higher at the V2 visit for Group I and Group II (35.6 versus 30.9%). Even with no placebo control and short of LUTS medication control, the use of 5-mg once-daily or alternate-day treatment with tadalafil was well tolerated in patients and effectively improved the IIEF score, IPSS score and SEP Q3 percentage. Management of patients with 5-mg alternate-day tadalafil could be adequate for regular use in patients with ED and LUTS.

Combination therapy of testosterone enanthate and tadalafil on PDE5 inhibitor non-reponders with severe and intermediate testosterone deficiency.

Several studies have suggested combination therapy with testosterone supplementation in patients not responding to PDE5 inhibitors. Considering the pathophysiological basis for testosterone supplementation, the present study aims to identify whether combination therapy allows persistence of treatment effect after testosterone discontinuation. Furthermore, we evaluated whether the degree of testosterone depletion affects treatment outcome from combination therapy. Hypogonadal patients (<350 ng dl(-1)) with erectile dysfunction who previously did not respond to PDE5 inhibitors were treated with testosterone enanthate injections and daily tadalafil. Patients were stratified into two groups depending on the level of testosterone deficiency, with 250 ng dl(-1) as a reference point. Following testosterone supplementation (12 weeks) and combination therapy (12 weeks), patients with severe testosterone deficiency showed higher IIEF (International Index of Erectile Function) erectile function (EF) domain score (16.47±4.019 vs 12.36±4.051, P=0.001) and more patients responding satisfactorily to treatment by general assessment (57.9 vs 16.0%, P=0.009), despite reaching similar levels of serum total testosterone (602±169 ng dl(-1) vs 698±165 ng dl(-1), P=0.057). Testosterone supplementation was then discontinued and patients were maintained only on daily tadalafil (12 weeks). The severe depletion group maintained higher EF domain scores than baseline (13.06±3.38 vs 7.20±2.24, P=0.0004), despite testosterone levels returning to baseline. The results suggest that combination therapy was more beneficial to patients with severe testosterone depletion, possibly by improving underlying pathophysiology.

The effects of intravesical chemoimmunotherapy with gemcitabine and Bacillus Calmette-Guérin in superficial bladder cancer: a preliminary study.

This prospective study investigated the long-term effects of intravesical chemoimmunotherapy with gemcitabine (GEM) and bacillus Calmette-Guérin (BCG; n = 36) versus BCG alone (n = 51) for the treatment of superficial bladder cancer. For the chemoimmunotherapy (GEM + BCG) group, GEM (1000 mg) was instilled immediately after transurethral resection of bladder tumour (TURBT) and again (2000 mg) 1 week later. From 2 to 7 weeks after TURBT, BCG was instilled into the bladder of all patients once weekly. The recurrence-free period of the GEM + BCG group (24.13 months) was significantly longer than that of the BCG monotherapy group (19.81 months). The overall recurrence rate was similar between the groups, although at 6 and 9 months post-TURBT, GEM + BCG produced a significantly lower rate of recurrence compared with BCG alone. This study suggests that intravesical chemoimmunotherapy with GEM + BCG is effective in reducing early tumour recurrence and in prolonging the recurrence-free period of superficial bladder cancer.

Long-term effects of glans penis augmentation using injectable hyaluronic acid gel for premature ejaculation.

The authors created the glans penis augmentation by injectable hyaluronic acid gel and reported the 6-month result for premature ejaculation. In a total of 38 patients, long-term effects of 5 years were compared to those of 6 months in terms of residual volume of implants and efficacy on premature ejaculation. Maximal glandular circumference measured by tapeline significantly decreased by 15% (P<0.05) but mean patient's visual estimation (Gr 0-Gr 4) did not decrease (3.60 vs 3.56, P>0.05). Compared to 6-month follow-up, intravaginal ejaculatory latency time and vibratory threshold decreased at 5 years (P<0.05), but still well increased considering those of preaugmentation. Hence, 76% of patients and 63% of partners were still satisfied. There was no serious adverse reaction. In the 5-year long-term follow-up of glans penis augmentation by filler, the implants were well maintained and effective for glans penis hypersensitivity in premature ejaculation patients.

The effects of long-term administration of oral desmopressin on the baseline secretion of antidiuretic hormone and serum sodium concentration for the treatment of nocturia: a circadian study.

PURPOSE: We assessed the effects of long-term oral desmopressin on serum sodium and baseline antidiuretic hormone secretion in elderly patients with nocturia. MATERIALS AND METHODS: A total of 15 elderly male patients with severe nocturia (greater than 3 voids nightly) who did not show hyponatremia within 7 days of administration of 0.2 mg desmopressin were enrolled in this study. Desmopressin (0.2 mg) was administered orally nightly for 1 year. Before and 1 month after the 1-year medication 24-hour circadian studies were performed to monitor changes in antidiuretic hormone. Every 3 months during the 1-year medication serum changes and timed urine chemistry were monitored. RESULTS: Desmopressin significantly decreased nocturnal urine output and the number of nocturia episodes (p<0.01). Compared to before treatment desmopressin gradually decreased serum sodium and induced statistically but not clinically significant hyponatremia after 6 months of treatment. After discontinuing desmopressin serum sodium returned to the normal range in all patients. There were no significant differences when baseline and posttreatment endogenous antidiuretic hormone were compared. No serious systemic complications were found during medication. CONCLUSIONS: Long-term desmopressin administration gradually decreased the serum concentration and induced significant hyponatremia from 6 months in patients who did not show initial hyponatremia. Long-term administration of desmopressin for 1 year in elderly patients did not affect baseline antidiuretic hormone secretion. For long-term desmopressin administration serum sodium should be assessed regularly, at least every 6 months.

Effect of TCDD on corpus cavernosum histology and smooth muscle physiology.

A polyhalogenated aromatic hydrocarbon, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), is one of the most potent toxic environmental pollutants. Decreases in spermatogenesis and the ability to conceive and carry a pregnancy to term are the most sensitive signs of reproductive toxicity by TCDD in the mammal, but no report of its effect on the erectile function exists. We performed this study to investigate the effect of TCDD on the erectile function. New Zealand white rabbits were treated intraperitoneally with 1 microg/kg of TCDD. At 4 (Gr I) and 8 (Gr II) weeks after the administration of TCDD, cavernosal tissues were harvested for strip study in the organ bath and testes were prepared for histologic examination. Compared to the maximal amplitude of 17.1+/-4.12 mN in normal control (Gr III), the contractions to cumulative concentrations of NE (10(-8)-10(-4) M) were significantly decreased to 6.57+/-1.34 and 5.45+/-1.01 mN in Groups I and II, respectively. Compared to 51.12+/-7.38% in Gr III, relaxation to cumulative concentration (10(-8)-10(-4) M) of acetylcholine was significantly decreased to 17.25+/-2.17% (Gr I) and 9.73+/-2.17% (Gr II) at a concentration of 10(-4) M, respectively. Compared to 75.12+/-13.18% in Gr III, relaxation to cumulative concentration (10(-8)-10(-4) M) of SNP was significantly decreased to 31.49+/-7.89% (Gr I) and 18.54+/-6.12% (Gr II) at a concentration of 10(-4) M, respectively. Histologically, intracavernosal fibrosis, abnormal subtunical deposition of fat and decreased sinusoidal space with consequent increase of trabecular smooth muscle contents were identified in TCDD-treated groups. In TCDD-treated animals, seminiferous tubules showed a decrease of germ cells with vacuolar degeneration and apoptotic cells. Spermatids were hardly seen. These results suggest that TCDD inhibits spermatogenesis and has a potential harmful effect on erectile function via changes of corpus cavernosum histology and smooth muscle physiology.

Effects of glans penis augmentation using hyaluronic acid gel for premature ejaculation.

The main limitation of medical treatment for premature ejaculation is recurrence after withdrawal of medication. We evaluated the effect of glans penis augmentation using injectable hyaluronic acid (HA) gel for the treatment of premature ejaculation via blocking accessibility of tactile stimuli to nerve receptors. In 139 patients of premature ejaculation, dorsal neurectomy (Group I, n=25), dorsal neurectomy with glandular augmentation (Group II, n=49) and glandular augmentation (Group III, n=65) were carried out, respectively. Two branches of dorsal nerve preserving that of midline were cut at 2 cm proximal to coronal sulcus. For glandular augmentation, 2 cc of HA was injected into the glans penis, subcutaneously. At 6 months after each procedure, changes of glandular circumference were measured by tapeline in Groups II and III. In each groups, ejaculation time, patient's satisfaction and partner's satisfaction were also assessed. There was no significant difference in preoperative ejaculation time among three groups. Preoperative ejaculation times were 89.2+/-40.29, 101.54+/-59.42 and 96.5+/-52.32 s in Groups I, II and III, respectively. Postoperative ejaculation times were significantly increased to 235.6+/-58.6, 324.24+/-107.58 and 281.9+/-93.2 s in Groups I, II and III, respectively (P<0.01). The percentage of postoperative satisfaction in both patient and his partner was 68% (17/25) and 44% (7/16) in Group I, 80% (39/49) and 66% (25/38) in Group II and 75% (49/65) and 62% (32/52) in Group III, respectively. Maximal glandular girth was significantly increased from 9.16+/-0.59 to 10.95+/-0.4 cm in Group II and 8.95+/-0.54 to 11.67+/-0.71 cm in Group III, respectively. These results suggest that glandular augmentation with injectable HA gel is a safe and effective modality to reduce sensory of glans penis. Long-term follow-up for residual volume and efficacy should be requested to establish its precise therapeutic potentials in premature ejaculation.

Human glans penis augmentation using injectable hyaluronic acid gel.

Although augmentation phalloplasty is not an established procedure, some patients still need enlargement of their penis. Current penile augmentation is girth enhancement of penile body by dermofat graft. We performed this study to identify the efficacy and the patient's satisfaction of human glans penis augmentation with injectable hyaluronic acid gel. In 100 patients of subjective small penis (Group I) and 87 patients of small glans after dermofat graft (Group II), 2 cm(3) of hyaluronic acid gel was injected into the glans penis, subcutaneously. At 1 y after injection, changes of glandular diameter were measured by tapeline. Patient's visual estimation of glandular size (Gr 0-4) and patient's satisfaction (Grade (Gr) 0-4) were evaluated, respectively. Any adverse reactions were also evaluated. The mean age of patients was 42.2 (30-70) y in Group I and 42.13 (28-61) y in Group II. The maximal glandular circumference was significantly increased compared to basal circumference of 9.13+/-0.64 cm in Group I (P<0.01) and 9.49+/-1.05 cm in Group II (P<0.01) at 1 y after injection. Net increase of maximal glandular circumference after glans augmentation was 14.93+/-0.80 mm in Group I and 14.78+/-0.89 mm in Group II. In patient's visual estimation, more than 50% of injected volume was maintained in 95% of Group 1 and 100% of Group II. The percentage of postoperative satisfaction (Gr 4, 5) was 77% in Group 1 and 69% in Group II. There was no abnormal reaction in area feeling, texture, and color. In most cases, initial discoloration by glandular swelling recovered to normal within 2 weeks. There were no signs of inflammation and no serious adverse reactions in all cases. These results suggest that injectable hyaluronic acid gel is a safe and effective material for augmentation of glans penis.

Augmentation of glans penis using injectable hyaluronic acid gel.

Recently, injectable hyaluronic acid gel has been widely used in soft-tissue augmentation. We performed this study to identify the feasibility of hyaluronic acid gel for the augmentation of the glans penis. In experiment I, 0.2 cm(3) of hyaluronic acid gel (HA) was injected into the dermis of the glans penis of 25 New Zealand white rabbits via a 30 G needle. At 3, 7, 14, 30, and 90 days after injection, histological changes of glans were studied, respectively. In experiment II, 0.5 cm(3) of HA was injected into the dermis of the glans penis of 14 Beagle dogs via a 27 G needle. At 6 months after injection, histological changes of the glans penis were also evaluated. At the time of autopsy, the lung, liver, and spleen were studied for systemic adverse reaction in each separate experiment. In experiment I, various sized cavities filled with amorphous basophilic materials were noted in the lamina propria and corpus spongiosum of the glans penis. All implants were positively stained on alcian blue. The intensity decreased in a time-dependent manner. Until 14 days, minimal inflammatory reactions were noted, but no signs of inflammation were identified at 90 days. With the gradual decrease of inflammation, fibrosis and deposition of collagen were noted. In experiment II, implants were well maintained at 6 months after injection in the lamina propria. Grade 1 of the inflammatory reaction was noted in one case. In both the experiments, all the specimens were free from any foreign body reaction and systemic adverse reactions. In conclusion, these results suggest that hyaluronic acid gel can be easily injected into the lamina propria of the glans penis and reside until 6 months. Injectable hyaluronic acid gel has a potential as a new bioimplant for the augmentation of the glans penis.

A double-blind, randomised- placebo, controlled, parallel group, multicentre, flexible-dose escalation study to assess the efficacy and safety of sildenafil administered as required to male outpatients with erectile dysfunction in Korea.

The efficacy and safety of sildenafil was evaluated in a randomiSed, double-blind, placebo-controlled, flexible-dose study in Korean men aged 28-78 y with erectile dysfunction (ED) of broad-spectrum aetiology and more than 6 months duration. A total of 133 patients were randomised at six centres in Korea to receive either sildenafil (50 mg initially, increased if necessary to l00 mg or decreased to 25 mg depending on efficacy and tolerance) (n=66) or matching placebo (n=67) taken on an 'as needed' basis l h prior to anticipated sexual activity for a period of 8 weeks. At the end of this time, the primary efficacy variables relating to the achievement and maintenance of erections sufficient for sexual intercourse, and the secondary efficacy variables, which included: (1) the five separate domains of sexual functioning of the International Index of Erectile Function (IIEF) scale, (2) the percentage of successful intercourse attempts, and (3) a global assessment of erections, were all statistically significantly improved by sildenafil in comparison with placebo (P&<0.0001). Treatment-related adverse events occurred in 56.1% of patients receiving sildenafil and 20.9% receiving placebo. The most common adverse events with sildenafil were vasodilatation (flushing), headache and abnormalities in colour vision (31.8, 22.7 and 6.1% of patients, respectively), and most were mild in nature. The efficacy and safety of sildenafil in this population of Korean men appears similar to that reported in other studies in western populations.

In vivo characterization of a prostate-specific antigen promoter-based suicide gene therapy for the treatment of benign prostatic hyperplasia.

To develop a novel gene therapeutic modality for the effective treatment of benign prostatic hyperplasia (BPH), we investigated the properties of toxic gene therapy utilizing prostate-specific antigen (PSA) promoter driving herpes simplex virus thymidine kinase (HSV-TK) suicide gene to induce highly selective molecular ablation of epithelial cells with minimal systemic toxicity in canine prostate. Replication-defective recombinant adenoviral vectors containing HSV-TK gene under transcriptional control of long PSA promoter (Ad-PSA-HSV-TK) were developed and delivered in an situ manner. Briefly, laparotomies were performed and Ad-PSA-HSV-TK (1 x 10(9) PFUs) was injected into the left lateral lobe of prostate only on days 1 and 7 with appropriate prodrug acyclovir in adult Beagle dogs. The therapeutic efficacy was evaluated on the 56th experimental day. The striking apoptosis of epithelial cells was identified in the treated left half of canine prostate on TUNEL assay. On immunohistochemical studies, there was markedly decreased number of PSA-secreting epithelial cells compared to control. Also significant atrophy of prostate glands, associated with dense infiltration of lymphocytes and plasma cells, was identified in the treated side. The PSA promoter-based suicide gene therapy induced highly selective and definite ablation of epithelial cells in benign canine prostate. Our novel approach could open opportunity of gene therapeutic modality for the treatment of clinical BPH.

Statin drugs and dietary isoprenoids downregulate protein prenylation in signal transduction and are antithrombotic and prothrombolytic agents.

Statins and various isoprenoids of dietary origins inhibit L-mevalonic acid synthesis, which in turn downregulates cholesterol and various other dependent substances, including farnesyl- and geranylgeranyl-conjugated proteins involved in cell signaling processes. Such signaling processes are stimulated by protease-activated receptor-1 (PAR-1), which upon activation, causes the expression of various substances including tissue factor (TF) and plasminogen activator inhibitor-1 (PAI-1). Tissue factor promotes thrombin generation, where thrombin stimulates a variety of cellular processes, as well as activating PAR-1 to produce more thrombin. Statins downregulate TF mitigating thrombin generation and also downregulate PAI-1, which normally consumes tissue plasminogen activator (tPA). In the absence of PAI-1, tPA activates plasminogen to generate plasmin. Thus, statins behave as antithrombotic agents and prothrombolytic agents.

The effects of a selective noradrenaline reuptake inhibitor on the urethra: an in vitro and in vivo study.

OBJECTIVE: To identify the effects of a selective noradrenaline reuptake inhibitor (venlafaxine) on urethral perfusion pressure (UPP) in rabbits and rats, and thus assess its therapeutic potential for treating stress urinary incontinence. MATERIALS AND METHODS: Strips of bladder and proximal urethra were prepared from female New Zealand White rabbits. Each strip was electrically stimulated and the contractile responses of controls strips compared with those after pretreatment with venlafaxine (100 micromol/L). In separate experiments using 80 adult female Sprague-Dawley rats (250-300 g), changes in intravesical pressure and UPP after the intra-arterial and intra-urethral administration of phenylephrine, phentolamine, fluoxetine and venlafaxine were monitored using double-lumen catheters. RESULTS: Pretreatment with venlafaxine significantly decreased the contraction of bladder strips (P=0.01) and significantly increased the contraction of urethral strips (P=0.008). In vivo, phenylephrine administered by both routes significantly increased UPP (P=0.02); phentolamine (arterial) significantly decreased UPP (P=0.001); fluoxetine (arterial) had no effect on UPP, and venlafaxine (both routes) significantly increased UPP (both P<0.001). The intravesical pressure was not changed significantly in any animal. CONCLUSIONS: Venlafaxine effectively increased UPP both in vitro and in vivo; these results imply that venlafaxine may be useful for treating stress urinary incontinence, by increasing the UPP.

Bisphenol A inhibits penile erection via alteration of histology in the rabbit.

Despite extensive research into the toxicity of bisphenol A (BPA), no report of its effect on erectile function exists. We performed this study to investigate the effect of BPA on erectile function. New Zealand white rabbits were treated intraperitoneally with 150 mg/kg of BPA every other day for 12 days (cumulative dose of 900 mg/kg). Four and 8 weeks after administration of BPA, the contractions and relaxation of cavernosal tissue strips were significantly suppressed in the BPA-treated animals compared to the control animals. Histologically, thickening of tunica albuginea, subtunical deposition of fat and decreased sinusoidal space with consequent increase of trabecular smooth muscle content were observed in the BPA-treated animals. These results suggest that xenoestrogen BPA may affect the erectile function through evident histological changes of the penis.

The influence of prostate volume on the prostate-specific antigen (PSA) level adjusted for the transition zone volume and free-to-total PSA ratio: a prospective study.

OBJECTIVES: To evaluate the influence of prostate volume on the prostate-specific antigen (PSA) level adjusted for the transition zone volume (PSAT) and free-to-total PSA ratio (f/tPSA) in detecting prostate cancer in men with intermediate PSA levels of 4.1-10.0 ng/mL. PATIENTS AND METHODS: From March 1997 to June 1999, the f/tPSA and PSAT were measured in 105 patients who underwent ultrasound-guided systemic biopsies and had a PSA level of 4.1-10.0 ng/mL, with an apparently normal prostate on a digital rectal examination. The PSAT and f/tPSA were evaluated in all patients and in subgroups of patients with small (< 40 mL) or large (> or = 40 mL) prostates, using receiver operating characteristic (ROC) curves. RESULTS: Total prostate volume was highly correlated with transition zone volume in all patients and in both subgroups (P < 0.001). In all 105 patients, PSAT had a sensitivity of 82% and its use would have avoided the largest number of unnecessary biopsies (87% specificity) at a threshold value of 0.35 ng. In men with small prostates f/tPSA and PSAT had a high sensitivity and specificity, at threshold values of 0.12 and 0.35 ng, respectively. In large prostates the PSAT was superior to f/tPSA in detecting prostate cancer. CONCLUSIONS: These results suggest that both f/tPSA and PSAT are useful in detecting prostate cancer in men with small prostates, while PSAT is superior to f/tPSA in detecting prostate cancer in men with large prostates.

Adenovirus-mediated suicide-gene therapy using the herpes simplex virus thymidine kinase gene in cell and animal models of human prostate cancer: changes in tumour cell proliferative activity.

OBJECTIVES: To determine the feasibility and efficacy of suicide-gene therapy using adenovirus (Ad)-mediated herpes simplex virus thymidine kinase (HSV-TK) and the prodrug acyclovir, and to evaluate changes in the biological phenotype for tumour cell proliferative activity after suicide-gene therapy in animal models of human prostate cancer. MATERIALS AND METHODS: Using a replication-defective adenoviral vector (cytomegalovirus, CMV) containing the beta-galactosidase gene (Ad-CMV-beta-gal) as a control and Ad-CMV-TK as the therapeutic vector under the transcriptional control of the CMV promoter, transduction efficiency was assessed in vitro by infecting LNCaP and PC-3 androgen-dependent and independent human prostate cancer cells with Ad-CMV-beta-gal, and using X-gal staining. The TK activity in prostate cancer cells infected with Ad-CMV-TK was determined by measuring TK-mediated [3H]-gancyclovir phosphorylation. The sensitivity of LNCaP and PC-3 cells to Ad-CMV-TK in vitro was determined after infection with the therapeutic vector with or without acyclovir. The inhibition of PC-3 tumour growth in vivo induced by the Ad-CMV-TK/acyclovir suicide-gene system was assessed in separate and controlled experiments using human prostate cancer mouse models. Ki-67 proliferative antigen and proliferating cell nuclear antigen (PCNA), both useful proliferative indices, were evaluated using immunohistochemical staining (MIB-1 monoclonal antibody and monoclonal anti-PCNA antibody) in formalin-fixed, paraffin-embedded tissues from gene therapy-treated and control animals. RESULTS: The mean TK activity was significantly higher in LNCaP and PC-3 cells infected with Ad-CMV-TK than in cells infected with Ad-CMV-beta-gal, used as a control (P < 0.05). The growth of human prostate cancer cells with Ad-CMV-TK was significantly inhibited by adding acyclovir in vitro (P < 0.05). In the in vivo experiments using the PC-3 human prostate cancer mouse model, tumour volume and growth was lower in mice treated with Ad-CMV-TK/acyclovir than in those treated with Ad-CMV-TK only, acyclovir only or untreated (controls) (P < 0.05). Histochemical staining of tumour tissues showed that Ad-CMV-TK/acyclovir destroyed PC-3 tumours through tumour cell death and apoptosis, with local lymphatic infiltration. The mean PCNA labelling index in prostate cancer cells of mice treated with Ad-CMV-TK/acyclovir was significantly lower than that in untreated controls (P < 0.05, Mann-Whitney U-test). The Ki-67 labelling index in prostate cancer cells of mice treated with Ad-CMV-TK/acyclovir was also lower than that in untreated controls (P < 0.05, Student's t-test). Adenovirus-mediated suicide-gene therapy using the HSV-TK gene decreased the proliferative activity of PC-3 human prostatic cancer cells in vivo. CONCLUSIONS: Adenovirus-mediated suicide-gene therapy using an HSV-TK/acyclovir system provided effective therapy in an experimental human prostate cancer mouse model, by significantly inhibiting tumour growth and decreasing the proliferative activity of human prostate cancer cells. Such therapy could be developed as a novel method for treating patients with androgen-independent prostate cancer.

Family risk and resiliency factors, substance use, and the drug resistance process in adolescence.

Recent approaches to drug prevention have emphasized risk and resiliency factors. Two models have been developed to explain these factors, one which posits that separate elements make up each set and the other which posits that a single factor can be either a risk or a resiliency factor depending on, for example, if it is present (resiliency) or absent (risk). This study tested these models and attempted to compare the effects of risk and resiliency across gender and ethnicity. Results support the model in which risk and resiliency are discrete sets of factors and demonstrate that overall resiliency factors play a larger role than risk factors in substance use and drug resistance processes. However, gender proved to be an important moderator of these effects. For adolescent males, resiliency has an indirect effect on overall substance use through age of first use, while risk has a direct effect on overall substance use. For adolescent females, resiliency has a direct effect on overall substance use and risk has an indirect effect through age of first use. This indicates that while early interventions are important for both genders, resiliency factors must be dealt with before initiation of substance use for males. Findings did not differ substantially across ethnicity, although the small African-American sample size may have limited power to detect differences.

Allium sativum potentiates suicide gene therapy for murine transitional cell carcinoma.

This study evaluated the synergistic effect of Allium sativum (AS) with suicide gene therapy for transitional cell carcinoma (TCC) of the bladder. Subcutaneous TCCs were established in syngeneic C3H/He mice with 1 x 10(5) MBT-2 cells. AS liquid extract was injected at the site of tumor transplantation on Day 1 for three weeks (Experiment I) and into the established tumors weekly for five weeks (Experiment II) in combination with or without gene therapy using a replication-defective adenoviral vector containing a herpes simplex virus thymidine kinase (HSV-TK) gene under the transcriptional control of Rous sarcoma virus (RSV) promoter (Ad-RSV-TK, 5 x 10(8) plaque-forming units) plus ganciclovir (20 mg/kg/day i.p.). AS demonstrated a statistically significant reduction in incidence of TCC (cumulative dose 25 mg of AS). Combination AS-suicide gene therapy significantly inhibited the tumor growth compared with the controls, which was evidenced by apoptosis on histomorphological and immunohistochemical studies. These results suggest that AS had a definite antitumor effect in inhibiting tumorigenesis and growth of TCC in a murine model. AS treatment combined with suicide gene therapy had significant additive antitumor effects on TCC and may provide a novel and effective treatment modality for TCC of the bladder.