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Introduction: Similar to bladder cancer, about one third of upper tract urothelial carcinoma (UTUC) present variant histology (VH). We aim to evaluate the incidence, clinical characteristics and the impact on outcomes of VH in UTUC., Methods: We consecutively enrolled 77 patients treated between 2009 and 2022 by radical surgery for UTUC from a secondary and a tertiary referral center. A pathology review of all specimens was performed by 1 independent uropathologist for each center. We compared pure UTUC and UTUC with VH and the accuracy of endoscopic biopsy. Descriptive and comparative analysis was performed to assess the association with clinical characteristics and the Kaplan-Meier estimator to compare outcomes., Results: Median follow-up after surgery was 51 months. VH was present in 21/77 (28%) patients and 4/21 (19%) patients had multiple variants. The most frequent VH was squamous 12/21 (57%), followed by glandular 7/21 (33%) and micropapillary 3/21 variants (14%). Neuroendocrine carcinoma was present in 2 patients. Nested variant was found in 1 patient. Muscle invasive tumor (≥pT2) was present in 30/56 (54%) patients with pure UTUC and in 18/21 (86%) patients with VH (P < 0.05). Presence of carcinoma in situ was seen in 24/56 (43%) patients with pure UTUC and in 16/21 (76%) with VH (P < 0.05). Cumulative 8/56 (14%) with pure UTUC had a nonintravesical recurrence (6 patients with local and 2 distant recurrence) compared to 8/21 (38%) (3 local, 3 nodal, 2 distant) in the subgroup with VH (P < 0.05). Opposite effect was noted for bladder recurrence: 60% for pure UTUC vs. 29% for tumors with VH (P < 0.05). Review of preoperative endoscopic biopsy did not show the presence of VH in any patients. Differences in outcomes did not reach significance: 3yr-OS 63% vs. 42% (P 0.28) and 3yr-CSS 77% vs. 50% (P 0.7)., Conclusion: Almost a third of UTUC present VH. Presence of VH is related to more aggressive tumor characteristics and associated with unfavorable outcomes. Due to a higher rate of extravesical recurrences in UTUC with VH, Follow-up controls should include cross sectional imaging and cystoscopy., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Background: The Decipher genomic classifier (GC) has shown to independently prognosticate outcomes in prostate cancer. The objective of this study was to validate the GC in a randomized phase III trial of dose-escalated salvage radiotherapy (SRT) after radical prostatectomy., Patients and Methods: A clinical-grade whole-transcriptome assay was carried out on radical prostatectomy samples obtained from patients enrolled in Swiss Group for Clinical Cancer Research (SAKK) 09/10, a phase III trial of 350 men with biochemical recurrence after radical prostatectomy randomized to 64 Gy versus 70 Gy without concurrent hormonal therapy or pelvic nodal RT. A prespecified statistical plan was developed to assess the impact of the GC on clinical outcomes. The primary endpoint was biochemical progression; secondary endpoints were clinical progression and time to hormone therapy. Multivariable analyses adjusted for age, T-category, Gleason score, postradical prostatectomy persistent prostate-specific antigen (PSA), PSA at randomization, and randomization arm were conducted, accounting for competing risks., Results: The analytic cohort of 226 patients was representative of the overall trial, with a median follow-up of 6.3 years (interquartile range 6.1-7.2 years). The GC (high versus low-intermediate) was independently associated with biochemical progression [subdistribution hazard ratio (sHR) 2.26, 95% confidence interval (CI) 1.42-3.60; P < 0.001], clinical progression (HR 2.29, 95% CI 1.32-3.98; P = 0.003), and use of hormone therapy (sHR 2.99, 95% CI 1.55-5.76; P = 0.001). GC high patients had a 5-year freedom from biochemical progression of 45% versus 71% for GC low-intermediate. Dose escalation did not benefit the overall cohort, nor patients with lower versus higher GC scores., Conclusions: This study represents the first contemporary randomized controlled trial in patients treated with early SRT without concurrent hormone therapy or pelvic nodal RT that has validated the prognostic utility of the GC. Independent of standard clinicopathologic variables and RT dose, high-GC patients were more than twice as likely than lower-GC patients to experience biochemical and clinical progression and receive of salvage hormone therapy. These data confirm the clinical value of Decipher GC to personalize the use of concurrent systemic therapy in the postoperative salvage setting., Competing Interests: Disclosure DES reports funding from Janssen; personal fees from Janssen, Blue Earth, AstraZeneca, and Boston Scientific. LP reports receiving an educational grant from AstraZeneca. DZ reports funding from Astellas, AstraZeneca, and Boston Scientific. VYTL, ED, HCH, YL, and XZ are employees of Decipher Biosciences (Veracyte Inc.). DJST is a contractor to Decipher Biosciences. All other authors have declared no conflicts of interest., (Copyright © 2022 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background: Although guidelines exist for advanced and variant bladder cancer management, evidence is limited/conflicting in some areas and the optimal approach remains controversial., Objective: To bring together a large multidisciplinary group of experts to develop consensus statements on controversial topics in bladder cancer management., Design: A steering committee compiled proposed statements regarding advanced and variant bladder cancer management which were assessed by 113 experts in a Delphi survey. Statements not reaching consensus were reviewed; those prioritised were revised by a panel of 45 experts before voting during a consensus conference., Setting: Online Delphi survey and consensus conference., Participants: The European Association of Urology (EAU), the European Society for Medical Oncology (ESMO), experts in bladder cancer management., Outcome Measurements and Statistical Analysis: Statements were ranked by experts according to their level of agreement: 1-3 (disagree), 4-6 (equivocal), 7-9 (agree). A priori (level 1) consensus was defined as ≥70% agreement and ≤15% disagreement, or vice versa. In the Delphi survey, a second analysis was restricted to stakeholder group(s) considered to have adequate expertise relating to each statement (to achieve level 2 consensus)., Results and Limitations: Overall, 116 statements were included in the Delphi survey. Of these, 33 (28%) statements achieved level 1 consensus and 49 (42%) statements achieved level 1 or 2 consensus. At the consensus conference, 22 of 27 (81%) statements achieved consensus. These consensus statements provide further guidance across a broad range of topics, including the management of variant histologies, the role/limitations of prognostic biomarkers in clinical decision making, bladder preservation strategies, modern radiotherapy techniques, the management of oligometastatic disease and the evolving role of checkpoint inhibitor therapy in metastatic disease., Conclusions: These consensus statements provide further guidance on controversial topics in advanced and variant bladder cancer management until a time where further evidence is available to guide our approach., (© The Author(s) 2019. Published by Oxford University Press on behalf of the European Society for Medical Oncology. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

One of the major challenges in prostate cancer (PCa) research is the identification of key players that control the progression of primary cancers to invasive and metastatic disease. The majority of metastatic PCa express wild-type p53, whereas loss of p63 expression, a p53 family member, is a common event. Here we identify inhibitor of apoptosis-stimulating protein of p53 (iASPP), a common cellular regulator of p53 and p63, as an important player of PCa progression. Detailed analysis of the prostate epithelium of iASPP transgenic mice, iASPP(Δ8/Δ8) mice, revealed that iASPP deficiency resulted in a reduction in the number of p63 expressing basal epithelial cells compared with that seen in wild-type mice. Nuclear and cytoplasmic iASPP expression was greater in PCa samples compared with benign epithelium. Importantly nuclear iASPP associated with p53 accumulation in vitro and in vivo. A pair of isogenic primary and metastatic PCa cell lines revealed that nuclear iASPP is enriched in the highly metastatic PCa cells. Nuclear iASPP is often detected in PCa cells located at the invasive leading edge in vivo. Increased iASPP expression associated with metastatic disease and PCa-specific death in a clinical cohort with long-term follow-up. These results suggest that iASPP function is required to maintain the expression of p63 in normal basal prostate epithelium, and nuclear iASPP may inactivate p53 function and facilitate PCa progression. Thus iASPP expression may act as a predictive marker of PCa progression.

We investigated vapor bubbles generated upon irradiation of gold nanoparticles with nanosecond laser pulses. Bubble formation was studied both with optical and acoustic means on supported single gold nanoparticles and single nanoparticles in suspension. Formation thresholds determined at different wavelengths indicate a bubble formation efficiency increasing with the irradiation wavelength. Vapor bubble generation in Bac-1 cells containing accumulations of the same particles was also investigated at different wavelengths. Similarly, they showed an increasing cell damage efficiency for longer wavelengths. Vapor bubbles generated by single laser pulses were about half the cell size when inducing acute damage.

Prostate cancer is the most common cancer among men in industrialised countries. Most patients with prostate cancer, however, will not die of it. As a result, many of them will experience symptomatic metastasis during the course of the disease. Prostate cancer has a high propensity to metastasize to bone. Unlike many other cancers prostate cancer cells induce a rather osteosclerotic than osteolytic reaction in the bone marrow by interfering with physiological bone remodelling. A proper understanding of the mechanisms of tumour cell-induced bone alterations and exaggerated bone deposition in prostate cancer may open new and urgently needed therapeutic approaches in the field of palliative care for affected patients. In this review we focus on the central role of two major regulators of bone mass, the wingless type integration site family members (WNTs) and the bone morphogenetic proteins (BMPs), in the development of osteosclerotic bone metastases.

Purpose: We evaluate the outcome in patients with node positive bladder cancer with particular reference to the effect of individual characteristics of positive nodes on survival after meticulous pelvic lymphadenectomy at cystectomy., Materials and Methods: This prospective analysis contains 452 cases of bladder cancer staged preoperatively as N0M0, managed with pelvic lymphadenectomy and cystectomy between 1984 and 1997. A total of 83 (18%) patients with histologically confirmed node positive disease are included in our study., Results: The median overall survival of patients with positive nodes was 20 months. Median 5-year survival was 29%. Patients who survived were found with positive nodes at each site in the pelvis. The median survival of 57 patients with less than 5 positive nodes was 27 months, compared with 15 months for 26 with 5 nodes or more (log-rank test p = 0.0027). Median survival of 26 patients with no lymph node capsule perforation was 93 months, compared with 16 months for 57 with capsule perforation (p = 0.0004). The median survival of 18 patients with a maximum diameter of lymph node metastasis up to 0.5 cm. was 64 months, compared with 16 months for 65 with nodal metastasis greater than 0.5 cm. (p = 0.024). Contralateral positive nodes were found in 16 of 39 (41%) patients with unilateral bladder cancer., Conclusions: Long-term survival is possible with node positive bladder cancer. Those patients with few as well as smaller and, therefore, unsuspected nodal metastases, and those without lymph node capsule perforation have the best results after removal of pelvic metastatic nodal disease. Because patients who survive may be found regardless of the site of pelvic nodal metastases, meticulous bilateral pelvic lymphadenectomy is warranted in all patients at the time of attempted curative cystectomy for bladder cancer, particularly if there is no clinical evidence of nodal involvement.

Purpose: We evaluate the predictive value of urinary cytokine levels of interleukin (IL) 8 and 18 for response in patients receiving intravesical bacillus Calmette-Guerin (BCG) for prevention of recurrences of superficial bladder cancer and treatment of carcinoma in situ., Materials and Methods: In 28 patients with superficial bladder cancer treated with BCG IL-8 expression in the urine during the first 6 hours after the first BCG instillation was determined. In 17 patients IL-18 levels were also evaluated during the first 12 hours after BCG instillation. IL-8 and 18 levels were determined by solid phase double ligand enzyme-linked immunosorbent assay., Results: In 12 of the 28 patients assessed for IL-8 expression disease recurred after a median followup of 66 months. Median IL-8 expression during the first 6 hours for these patients was 851 ng. (range 232 to 8,497). Median IL-8 expression during the first 6 hours in patients without recurrence was 4,200 ng. (range 432 to 12, 232). Of 8 patients with a followup of greater than 36 months 7 (88%) had no recurrent disease and IL-8 levels greater than 4,000 ng. Patients secreting more than 4,000 ng. IL-8 into the urine after BCG have a significantly higher chance of remaining disease-free (p <0.05), and those with elevated IL-18 expression have a significantly longer disease-free survival (p <0.05). After a median followup of 23 months (range 7 to 93) 6 of the 17 patients assessed for IL-18 expression had treatment failure. Median IL-18 expression in those patients during the first 12 hours was 2,632 pg. (range 860 to 8,298). Median IL-18 expression during the first 12 hours in patients without recurrence was 12,258 pg. (range 1,727 to 151,495)., Conclusions: In this study we confirmed the value of quantitative IL-8 expression in the urine during the first 6 hours after BCG instillation for superficial bladder cancer to predict freedom of disease. Furthermore, to our knowledge we report for the first time the potential value of IL-18 expression in the urine during the first 12 hours after BCG to predict freedom from disease. These findings may help improve the treatment of patients with superficial bladder cancer, especially by identifying those with a high risk of disease recurrence and progression after BCG therapy.

Background: Clinically, the lethal phenotypes of human prostate cancer are characterized by their progression to androgen-independence and their propensity to form osseous metastases. We reported previously on the establishment of androgen-independent (AI) human prostate cancer cell lines derived from androgen-dependent (AD) LNCaP cells, with androgen independence defined as the capability of prostate cancer cells to grow in castrated hosts. One of the sublines, C4-2, was found to be AI, highly tumorigenic, and metastatic, having a proclivity for metastasis to the bone., Methods: We established the AI and bone metastatic cell sublines B2, B3, B4, and B5 from the parental C4-2 subline, using a previously established coinoculating procedure. We determined the biologic behavior of the parental and derivative LNCaP sublines in vivo and in vitro, as well as their molecular and cytogenetic characteristics., Results: Unlike other human prostate cancer models, the LNCaP progression model shares remarkable similarities with human prostate cancer. We observed a comparable pattern of metastasis from the primary to the lymph node and to the axial skeleton, with a predominant phenotype of osteoblastic reaction; 25-37.5% of the animals developed paraplegia. Cytogenetic and biochemical characterizations of LNCaP sublines also indicate close similarities between human prostate cancer and the LNCaP progression model. Additional chromosomal changes were detected in B2-B5 sublines derived from C4-2 bone metastases. These LNCaP sublines were found to grow faster under anchorage-dependent but not -independent conditions. The in vitro invasion and in vivo metastatic potential of these LNCaP sublines surprisingly correlated with anchorage-dependent and not -independent growth. The derivative LNCaP sublines when cultured in vitro produced a substantially higher (20-30-fold) amount of basal steady-state concentrations of PSA than that of the parental LNCaP cells. PSA production was high initially, but was markedly reduced when the derivative cell lines were inoculated and allowed to grow long-term in vivo for the establishment of tumors and metastasis, suggesting that unknown host factors derived either from the prostate or the bone can effectively downregulate PSA expression by prostate tumor epithelium., Conclusions: The LNCaP model of human prostate cancer progression will help improve our understanding of the mechanisms of androgen-independence and osseous metastasis, and tumor-host determinants of PSA expression., (Copyright 2000 Wiley-Liss, Inc.)

Human prostate cancer has the propensity to metastasize to the bone where reciprocal cellular interactions between prostate cancer and bone cells are known to occur. Osteopontin (OPN), a noncollagenous bone extracellular matrix, is a secreted adhesive glycoprotein with a functional RGD cell-binding domain that interacts with the alpha(v)beta3 cell surface integrin heterodimer. OPN has been associated with malignant transformation as well as being ligand to the CD44 receptor. Polyclonal antibodies to human OPN (hOPN) were prepared, and specificity was shown by preabsorption with recombinant hOPN. The stimulatory effect of hOPN protein and the inhibitory effect of hOPN antibody on human prostate cancer cell lines LNCaP and C4-2 were assessed by induction or inhibition of anchorage-independent growth, respectively. Expression of hOPN mRNA in prostate cancer cell lines and human prostate cancer tissue specimens were measured by mRNA blot analysis. Protein expression was assessed by immunohistochemistry in human prostate cancer specimens and by Western blot analysis in prostate cancer cell lines. hOPN stimulated anchorage-independent growth of the human prostate cancer cell lines LNCaP and C4-2 in vitro. Antibodies to hOPN inhibited the growth-stimulatory effect by endogenous OPN, which can be overcome by the addition of exogenous hOPN. hOPN mRNA and protein are expressed in human prostate cancer cell lines in vitro and in clinical human prostate cancer specimens. These findings taken together suggest that OPN may act as a paracrine and autocrine mediator of prostate cancer growth and progression.

Purpose: We prospectively evaluated a decrease in outflow obstruction caused by benign prostatic hyperplasia (BPH) with second generation thermotherapy., Materials and Methods: Transurethral microwave therapy was given with local anesthesia to 134 patients with urodynamically and cystoscopically documented obstruction by BPH and preserved detrusor function. Of 134 patients 67 (50%) had a general health score of 3 or greater., Results: Urgency was the main complaint during thermotherapy. After a median followup of 24 months (minimum 12) 100 patients were evaluable at 6 and 12 months. Of the initial 134 patients 17 (13%) who required additional treatment (repeat thermotherapy, transurethral prostatic resection, permanent cystostomy), 7 who died during followup for treatment unrelated reasons and 10 who were lost to followup or refused evaluation were excluded from further analysis. Mean International Prostate Symptom Score decreased from 22.5 before to 3.6 at 6 months after treatment and remained stable at 12 months. Mean Quality of Life Index improved from 4.3 before to 1 at 12 months after treatment. Mean maximum flow increased from 7.3 ml. per second before to 14.5 at 6 months and 13.9 at 12 months after treatment. Mean post-void residual decreased from 199 to 34.8 and 37.2 ml. at 6 and 12 months, respectively. Urodynamic evaluation of 84 patients after 6 months revealed a decrease in mean detrusor opening pressure from 96.8 to 53 cm. water and mean detrusor pressure at maximum flow from 99.8 to 59.7 cm. water. Mean ultrasonographic prostate volume decreased from 57.6 to 42.4 cc and a cavity in the prostate was documented in 65 of the 84 cases (77%). All changes between the pretreatment and posttreatment values at 6 and 12 months, respectively, were statistically significant (paired t test p<0.00001)., Conclusions: Targeted transurethral thermotherapy with second generation microwave equipment is minimally invasive, easy to apply and generally well tolerated with local anesthesia. Infravesical outlet obstruction and voiding pressures as assessed by pressure flow studies significantly decreased 6 months after treatment. Subjective voiding symptoms as well as post-void residual urine were significantly decreased, and urinary flow was improved 6 and 12 months after treatment of documented BPH.

LNCaP lineage-derived human prostate cancer cell lines C4-2 and C4-2B4 acquire androgen independence and osseous metastatic potential in vivo. Using C4-2 and C4-2B4 the goals of the current investigation were 1) to establish an ideal bone xenograft model for prostate cancer cells in intact athymic or SCID/bg mice using an intraosseous route of tumor cell administration and 2) to compare prostate cancer metastasis by administering cells either through intravenous (i.v.) or intracardiac administration in athymic or SCID/bg mice. Subsequent to tumor cell administration, prostate cancer growth in the skeleton was assessed by radiographic bone density, serum prostate-specific antigen (PSA) levels, presence of hematogenous prostate cancer cells and histopathologic evaluation of tumor specimens in the lymph node and skeleton. Our results show that whereas LNCaP cells injected intracardially failed to develop metastasis, C4-2 cells injected similarly had the highest metastatic capability in SCID/bg mice. Retroperitoneal and mediastinal lymph node metastases were noted in 3/7 animals, whereas 2/7 animals developed osteoblastic spine metastases. Intracardiac injection of C4-2 in athymic hosts produced spinal metastases in 1/5 animals at 8-12 weeks post-injection; PC-3 injected intracardially also metastasized to the bone but yielded osteolytic responses. Intravenous injection of either LNCaP or C4-2 failed to establish tumor colonies. Intrailiac injection of C4-2 but not LNCaP nor C4-2B4 cells in athymic mice established rapidly growing tumors in 4/8 animals at 2-7 weeks after inoculation. Intrafemoral injection of C4-2 (9/16) and C4-2B4 (5/18) but not LNCaP (0/13) cells resulted in the development of osteoblastic bone lesions in athymic mice (mean: 6 weeks, range: 3-12 weeks). In SCID/bg mice, intrafemoral injection of LNCaP (6/8), C4-2 (8/8) and C4-2B4 (8/8) cells formed PSA-producing, osteoblastic tumors in the bone marrow space within 3-5 weeks after tumor cell inoculation. A stepwise increase of serum PSA was detected in all animals. Reverse transcription-polymerase chain reaction (RT-PCR) to detect hematogenously disseminated prostate cancer cells could not be correlated to either serum PSA level or histological evidence of tumor cells in the marrow space. We have thus established a PSA-producing and osteoblastic human prostate cancer xenograft model in mice.

Purpose: We assessed whether interleukin-8 (IL-8), one of the first cytokines expressed in the urine after bacillus Calmette-Guerin (BCG) therapy for superficial urothelial tumors, may serve as a prognostic factor for treatment response., Materials and Methods: Of 20 patients with superficial urothelial cancer of the urinary tract treated with BCG 13 had superficial bladder cancer and 7 received BCG perfusion of the upper urinary tract due to inoperability, solitary kidney, renal insufficiency or bilateral disease. After intravesical instillation of 120 mg. BCG or after 2-hour perfusion of the upper urinary tract with 360 mg. BCG urine was collected at 6-hour intervals. IL-8 was determined by solid phase double ligand enzyme-linked immunosorbent assay., Results: IL-8 was stable in the urine for more than 48 hours. At a median followup of 36.5 months treatment failure occurred in 10 of the 20 patients, including 3 with recurrence, 6 with progressive disease and 1 with extensive carcinoma in situ. IL-8 excretion was more than 4,000 ng. in the first 6 hours after BCG therapy in all 10 patients who remained disease-free. In 9 of the 10 patients with recurrent disease IL-8 excretion was less than 4,000 ng. in the first 6 hours after BCG therapy. Patients secreting less than 4,000 ng. IL-8 into the urine during the first 6 hours after BCG therapy had a significantly higher risk of tumor recurrence and progression (p <0.0002)., Conclusions: Due to its stability and kinetics IL-8 determined in urine collected during the first 6 hours after BCG therapy may prove to be a prognostic factor for tumor recurrence and progression after BCG therapy.

Background: We assessed the frequency and molecular basis of p53 mutations in clinically localized prostatic adenocarcinoma., Methods: Prostate specimens were examined from 100 patients with clinically localized prostatic adenocarcinoma and 13 patients with benign prostatic hyperplasia (BPH). Mutations producing nuclear accumulation of p53 were detected immunohistochemically. Exon-specific mutations were analyzed by polymerase chain reaction amplification and single strand conformation polymorphism (PCR-SSCP) and sequenced., Results: p53 accumulation was detected in 5 tumors using antibody DO-1, and in 4 of these using antibody PAb 1801, but not in BPH. PCR-SSCP detected mutations in all 5 tumors, with alterations in exon 5 for 1 tumor, exon 6 for 3 tumors, and exon 7 for 1 tumor. An exon 6 mutation was also found in a tumor with no anti-p53 staining., Conclusions: p53 mutations are uncommon in clinically localized prostatic adenocarcinoma and absent from BPH. 5 of the 6 mutations were derived from locally invasive, prostate carcinomas, supporting the hypothesis that mutation of p53 is a late event in prostate carcinoma progression.

Purpose: Intestinal low pressure orthotopic bladder substitutes have no major coordinated contractions during micturition. Therefore, the importance and type of reflux prevention were assessed in a prospective randomized study., Materials and Methods: A total of 70 patients with an ileal low pressure bladder substitute was randomized to receive a nipple valve or an isoperistaltic afferent ileal tubular segment for reflux prevention., Results: After median observation times of 57 and 45 months, respectively, the results regarding functional reservoir capacity, incidence of infected urine, urinary continence, voiding habits and serum electrolytes, urea and creatinine were similar in both groups. Severe upper tract dilatation due to ureteroileal or nipple stenosis occurred in 9 of 67 evaluable reno-ureteral units (13.5%) in patients with antireflux nipples and in 2 of 69 (3%) in patients with an afferent tubular segment. This difference in favor of the latter cases is significant (Fisher's exact test p < 0.03). Video urodynamics did not show reflux of contrast medium during voiding in either group. A simultaneous intravesical, intra-abdominal and intrapelvic pressure increase was noted during the Valsalva maneuver., Conclusions: While long-term upper tract preservation by an afferent tubular ileal segment must be confirmed in larger patient series with longer followup, our results indicate that reflux prevention in patients with orthotopic low pressure bladder substitutes is not a major concern and does not justify the use of antireflux mechanisms with a high complication rate.

The lethal phenotypes of advanced prostate cancer are androgen independent (AI) and metastatic to the axial skeleton. Our laboratory has developed an AI mouse model of metastatic human prostate cancer. In this communication, we report the development of tumor suppressor gene therapy in this AI and metastatic (C4-2) cancer model. By using recombinant adenovirus as a delivery vehicle, we introduced a wild-type p53 tumor suppressor gene into prostate cancer cell lines. Despite a silent mutation at codon 152 of the p53 gene, C4-2 cells express functional, but low, levels of p53 protein. However, the other prostatic cell lines, PC-3 and DU145, have a deletion mutation and two point mutations of the p53 gene, respectively. In vitro studies showed that cell growth, as measured by the thymidine incorporation assay, was inhibited in the C4-2, PC-3, and DU145 cells infected with wild-type p53 adenovirus in comparison to control viruses. Recombinant wild-type p53 adenovirus inhibited prostate tumor growth and its production of prostate-specific antigen (PSA) when injected into C4-2 tumors in nude mice. All p53-treated mice were tumor free as long as 12 weeks after cessation of the 8-week treatment regimen. Two of 8 p53-treated mice developed small tumors growing at distant sites after a prolonged period of follow-up observation. Moreover, other AI prostate cancer cells, PC-3 and DU145, treated with Ad5-CMV-p53 failed to develop into tumors in vivo. This gene therapy strategy may be used against AI prostatic cancer regardless of p53 gene mutation status.

Background: Suramin, a polysulfonated naphthylurea and a recognized antitrypanosomal agent, has shown some promise in phase II clinical trials in the management of hormone-refractory human prostate cancer. Reduction of serum prostate-specific antigen (PSA) levels has been proposed as an end point for evaluating the antitumor efficacy of treatments for hormone-refractory prostate cancer., Purpose: We examined the antitumor effect of suramin in an in vivo mouse model of hormone-refractory human prostate cancer to determine whether a decrease in PSA levels reflects a reduction in tumor growth (volume). The tumors were induced in castrated, athymic nude mice by use of the androgen-independent, tumorigenic human prostate cancer cell line C4-2, which is a subline of the androgen-dependent, parental nontumorigenic cell line LNCaP. We also evaluated the effects of suramin in vitro on cell growth and the expression of PSA messenger RNA (mRNA) in both LNCaP and C4-2 cells., Methods: For the in vivo studies, 24 mice were given a subcutaneous injection of 5 x 10(6) C4-2 cells at each of four sites. Animals (n = 20) with tumor volumes greater than 1 mm3 or less than 5 mm3 were divided equally into two groups. Drug treatment was initiated in one group by administration of 1 mg suramin intraperitoneally, followed by 0.1 mg suramin at 10-day intervals to maintain constant serum levels. Tumor growth and PSA expression levels were monitored. For the in vitro studies, both LNCaP and C4-2 cells were exposed to 100-400 microgram/mL suramin, and cell growth was monitored by a quantitative crystal violet assay. PSA mRNA expression was assessed by northern blot analysis in cells treated with either 250 microgram/mL suramin, 400 ng/mL dihydrotestosterone (DHT) (positive control), or 0.5-75 microgram/mL hydrocortisone (to mimic the clinical use of hydrocortisone during suramin treatment to compensate for the loss of adrenocortical function). In some studies, the combined effect of DHT and suramin on PSA mRNA expression was also evaluated. A two-way analysis of variance was performed to evaluate the treatment differences, and P values were obtained from two-sided tests for statistical significance., Results: In vivo, suramin did not significantly affect the growth of androgen-independent C4-2 tumors (relative to the growth of tumors in 5% glucose-treated control animals; P = .76). However, suramin significantly decreased the ratio of PSA level to tumor volume (ng/mL PSA per mm(3) of tumor) (P<.001). Mice developed bone metastases in both treatment arms. Suramin affected the in vitro growth of LNCaP cells but not of C4-2 cells. Suramin diminished PSA mRNA expression in both LNCaP and C4-2 cells grown in vitro. Hydrocortisone had no effect on PSA mRNA levels., Conclusions: Although suramin inhibited the growth of androgen-dependent LNCaP cells, it did not inhibit the growth of androgen-independent C4-2 cells either in vitro or in vivo. Suramin significantly decreased PSA mRNA expression in both cell lines in vitro and depressed serum PSA levels in mice bearing androgen-independent C4-2 tumors., Implications: PSA level should be used with caution as an end point in clinical trials using suramin therapy for hormone-refractory prostate cancer.

Our laboratory has previously reported on the derivation of LNCaP cell sublines from LNCaP tumors maintained in castrated and intact athymic male mice. These LNCaP sublines differ from the parental line in tumorigenicity and androgen dependence. This paper demonstrates that one of these sublines acquired metastatic potential. When inoculated either s.c. or orthotopically, the C4-2 subline metastasized to the lymph node and bone with an incidence of 11-50%. Interestingly, the incidence of osseous metastasis was higher in castrated than in intact male hosts. We evaluated the chromosomal, immunohistochemical, and biochemical characteristics of the LNCaP sublines derived from C4-2 tumors that metastasized to the lymph node and bone. Cytogenetic analysis showed that all sublines were human and shared common marker chromosomes with the parental LNCaP cells. This experimental human prostate cancer model may permit, for the first time, the study of the molecular mechanisms underlying human prostate cancer metastasis.