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Background: Androgen signaling is central to prostate cancer and men’s health. Prior data indicates that increasing body fat is unfavorable in the localized setting yet associated with favorable outcomes in men with metastatic disease. Understanding the biological links between adiposity and prostate cancer may optimize the therapeutic index with ASI. We hypothesized that host adiposity and androgen synthesis are linked to the efficacy and toxicity of ASI for men with metastatic castration-resistant prostate cancer (mCRPC). Methods: A post-hoc analysis was done of NCT02703623 where men with mCRPC (n= 186) were treated for 8 weeks with abiraterone acetate, prednisone, and apalutamide (AAPA), and a satisfactory response was defined as a PSA decline >50%. Body composition was measured on baseline CT scans. Germline DNA WES was performed with a focus on variants in steroidogenic genes. Adipokine levels were measured in pre-treatment plasma. Results: Germline polymorphisms in 3 genes involved in androgen synthesis (AKR1C3rs12529, CYP17A1rs6162, SRD5A2rs523349) were associated with differences in body composition at baseline on ADT alone (prior to receipt of AAPA). Elevated subcutaneous adipose tissue index (SATi, p= 0.02), visceral adipose tissue index (VATi, p= 0.03), and BMI (p= 0.04) were associated with satisfactory response to AAPA. Leptin had positive correlation with VATi (r= 0.47) and SATi (r= 0.48). Conclusion: Inherited polymorphisms in androgen synthesis correlated with differences in body composition after exposure to ADT and warrant further investigation as candidate markers for body composition toxicity. Elevated subcutaneous and visceral adiposity were associated with improved response to ASI.

The transferability and clinical value of genetic risk scores (GRSs) across populations remain limited due to an imbalance in genetic studies across ancestrally diverse populations. Here we conducted a multi-ancestry genome-wide association study of 156,319 prostate cancer cases and 788,443 controls of European, African, Asian and Hispanic men, reflecting a 57% increase in the number of non-European cases over previous prostate cancer genome-wide association studies. We identified 187 novel risk variants for prostate cancer, increasing the total number of risk variants to 451. An externally replicated multi-ancestry GRS was associated with risk that ranged from 1.8 (per standard deviation) in African ancestry men to 2.2 in European ancestry men. The GRS was associated with a greater risk of aggressive versus non-aggressive disease in men of African ancestry (P= 0.03). Our study presents novel prostate cancer susceptibility loci and a GRS with effective risk stratification across ancestry groups.

Background: Prostate cancer (PCa) typically spreads to the bone, and this distribution is attributed to the central role of the microenvironment in progression. However, metastasis to the adrenal glands, while not as common, does occur. The biology that accounts for adrenal metastases may be attributed to the unique local steroid metabolome and co-clinical characterization may elucidate the role steroid biosynthesis plays in PCa progression. Methods: Three patients with metastatic PCa who had archived tumor tissue from an adrenalectomy were retrospectively identified, and one adrenal metastasis was developed into a xenograft (MDA-PCa-250). The adrenal metastases were characterized by performing somatic DNA whole exome sequencing (WES), RNA-Seq, immunohistochemistry (IHC), and steroid metabolite quantitation. The influence of steroid metabolites on adrenal metastasis cells and tumor growth was tested in vitro and in vivo. Results: Clinically, adrenalectomy was performed during castration-resistant oligometastatic disease, and two men experienced resensitization to leuprolide. Somatic DNA WES revealed heterogeneous alterations in tumor suppressor and DNA damage repair pathway genes. Adrenal metastases had active androgen receptor (AR) signaling by IHC, and RNA-Seq supported a potential role for adrenal androgen precursor metabolism in activating the AR. Steroid quantitation suggested the adrenal androgen precursors were converted into testosterone in these metastases, and stable isotope tracing of an organoid from MDA-PCa-250 confirmed the capability of adrenal metastases to biosynthesize testosterone from adrenal precursors. In vitro testing of a cell line derived from MDA-PCa-250 showed that testosterone and cortisol stimulated tumor cell growth. In vivo experiments demonstrated that MDA-PCa-250 grew in intact mice with circulating testosterone, but not in castrated mice. Conclusions: PCa adrenal metastases depend upon AR signaling driven by androgen precursors, androstenedione and dehydroepiandrosterone, available in the microenvironment, despite the presence of heterogeneous somatic DNA alterations. Moreover, MDA-PCa-250 provides a preclinical model that can recapitulate the unique androgen-dependence of adrenal metastases. Clinical trial registration: This study does not report the clinical results of a clinical trial, but it does use samples from a completed clinical trial that is registered with clinicaltrials.gov (NCT01254864).

Background Secondary analyses of two randomized, controlled phase III trials demonstrated that selenium and vitamin E could reduce prostate cancer incidence. To characterize pharmacodynamic and gene expression effects associated with use of selenium and vitamin E, we undertook a randomized, placebo-controlled phase IIA study of prostate cancer patients before prostatectomy and created a preoperative model for prostatectomy tissue interrogation. Methods Thirty-nine men with prostate cancer were randomly assigned to treatment with 200 [micro]g of selenium, 400 lU of vitamin E, both, or placebo. Laser capture microdissection of prostatectomy biopsy specimens was used to isolate normal, stromal, and tumor cells. Gene expression in each cell type was studied with microarray analysis and validated with a real-time polymerase chain reaction (PCR) and immunohistochemistry. An analysis of variance model was fit to identify genes differentially expressed between treatments and cell types. A beta-uniform mixture model was used to analyze differential expression of genes and to assess the false discovery rate. All statistical tests were two-sided. Results The highest numbers of differentially expressed genes by treatment were 1329 (63%) of 2109 genes in normal epithelial cells after selenium treatment, 1354 (66%) of 2051 genes in stromal cells after vitamin E treatment, and 329 (56%) of 587 genes in tumor cells after combination treatment (false discovery rate = 2%). Validation of 21 representative genes across all treatments and all cell types yielded Spearman correlation coefficients between the microarray analysis and the PCR validation ranging from 0.64 (95% confidence interval [CI] = 0.31 to 0.79) for the vitamin E group te 0.87 (95% CI = 0.53 to 0.99) for the selenium group. The increase in the mean percentage of p53-positive tumor cells in the selenium-treated group (26.3%), compared with that in the placebo-treated group (5%), showed borderline statistical significance (difference = 21.3%; 95% CI = 0.7 to 41.8; P = .051). Conclusions We have demonstrated the feasibility and efficiency of the preoperative model and its power as a hypothesis-generating engine. We have also identified all type- and zone-specific tissue effects of interventions with selenium and vitamin E that may have clinical implications.

Metastatic prostate cancer (PCa) in bone induces bone-forming lesions that enhance PCa progression. How tumor-induced bone formation enhances PCa progression is not known. We have previously shown that PCa-induced bone originates from endothelial cells (ECs) that have undergone endothelial-to-osteoblast (EC-to-OSB) transition by tumor-secreted bone morphogenetic protein 4 (BMP4). Here, we show that EC-to-OSB transition leads to changes in the tumor microenvironment that increases the metastatic potential of PCa cells. We found that conditioned medium (CM) from EC-OSB hybrid cells increases the migration, invasion, and survival of PC3-mm2 and C4-2B4 PCa cells. Quantitative mass spectrometry (Isobaric Tags for Relative and Absolute Quantitation) identified Tenascin C (TNC) as one of the major proteins secreted from EC-OSB hybrid cells. TNC expression in tumor-induced OSBs was confirmed by immunohistochemistry of MDA PCa-118b xenograft and human bone metastasis specimens. Mechanistically, BMP4 increases TNC expression in EC-OSB cells through the Smad1-Notch/Hey1 pathway. How TNC promotes PCa metastasis was next interrogated by in vitro and in vivo studies. In vitro studies showed that a TNC-neutralizing antibody inhibits EC-OSB-CM-mediated PCa cell migration and survival. TNC knockdown decreased, while the addition of recombinant TNC or TNC overexpression increased migration and anchorage-independent growth of PC3 or C4-2b cells. When injected orthotopically, PC3-mm2-shTNC clones decreased metastasis to bone, while C4-2b-TNC-overexpressing cells increased metastasis to lymph nodes. TNC enhances PCa cell migration through α5β1 integrin-mediated YAP/TAZ inhibition. These studies elucidate that tumor-induced stromal reprogramming generates TNC that enhances PCa metastasis and suggest that TNC may be a target for PCa therapy.

Background: Prostate cancer risk stratification using single-nucleotide polymorphisms (SNPs) demonstrates considerable promise in men of European, Asian, and African genetic ancestries, but there is still need for increased accuracy. We evaluated whether including additional SNPs in a prostate cancer polygenic hazard score (PHS) would improve associations with clinically significant prostate cancer in multi-ancestry datasets. Methods: In total, 299 SNPs previously associated with prostate cancer were evaluated for inclusion in a new PHS, using a LASSO-regularized Cox proportional hazards model in a training dataset of 72,181 men from the PRACTICAL Consortium. The PHS model was evaluated in four testing datasets: African ancestry, Asian ancestry, and two of European Ancestry—the Cohort of Swedish Men (COSM) and the ProtecT study. Hazard ratios (HRs) were estimated to compare men with high versus low PHS for association with clinically significant, with any, and with fatal prostate cancer. The impact of genetic risk stratification on the positive predictive value (PPV) of PSA testing for clinically significant prostate cancer was also measured. Results: The final model (PHS290) had 290 SNPs with non-zero coefficients. Comparing, for example, the highest and lowest quintiles of PHS290, the hazard ratios (HRs) for clinically significant prostate cancer were 13.73 [95% CI: 12.43–15.16] in ProtecT, 7.07 [6.58–7.60] in African ancestry, 10.31 [9.58–11.11] in Asian ancestry, and 11.18 [10.34–12.09] in COSM. Similar results were seen for association with any and fatal prostate cancer. Without PHS stratification, the PPV of PSA testing for clinically significant prostate cancer in ProtecT was 0.12 (0.11–0.14). For the top 20% and top 5% of PHS290, the PPV of PSA testing was 0.19 (0.15–0.22) and 0.26 (0.19–0.33), respectively. Conclusions: We demonstrate better genetic risk stratification for clinically significant prostate cancer than prior versions of PHS in multi-ancestry datasets. This is promising for implementing precision-medicine approaches to prostate cancer screening decisions in diverse populations.

Background: The clinical behavior of the tumor in patients with locally advanced bladder carcinoma is unpredictable. Current predictors of clinical behavior include depth of muscle invasion, presence of vascular invasion, proliferation rate, and loss of blood group antigens. Treatment selection would be facilitated by the development of a reliable marker of tumor progression. Functional retinoblastoma (RB) gene loss has been reported to occur in bladder carcinoma, but the significance of this loss is unknown. Purpose: We have evaluated the frequency of functional loss of the RB gene in locally advanced bladder carcinoma and have compared the results to known prognostic factors in the same cohort. Methods: Forty-three study patients with pathologically well-characterized, locally advanced bladder carcinoma, who were placed in a protocol incorporating surgery and chemotherapy, were studied for known clinical and pathological prognostic indicators as well as for their Rb status. Formalin-fixed and paraffin-embedded archival primary tumor tissues were used for histological and immunohistochemical analyses. Results: Altered Rb protein expression was documented in 37% of the tumor specimens. The high rate of altered Rb expression found in this cohort with advanced urothelial tumors strongly suggests that RB functional loss may be associated with tumor progression in this malignancy. Altered Rb protein expression was found to be independent of other known prognostic variables. A significantly poorer tumor-free survival rate also was noted for those patients who had a tumor with an altered Rb protein with or without vascular invasion. Conclusion: The high frequency of Rb alteration in locally advanced bladder carcinomas, plus the fact that a significant correlation could not be found between the Rb status and other known prognostic markers in this preliminary study, suggests that altered Rb expression may be an independent prognostic marker of tumor progression in bladder cancer. [J Natl Cancer Inst 84:1256-1261, 1992]

Yes-associated protein 1 (YAP1), a key player in the Hippo pathway, has been shown to play a critical role in tumor progression. However, the role of YAP1 in prostate cancer cell invasion, migration, and metastasis is not well defined. Through functional, transcriptomic, epigenomic, and proteomic analyses, we showed that prolyl hydroxylation of YAP1 plays a critical role in the suppression of cell migration, invasion, and metastasis in prostate cancer. Knockdown (KD) or knockout (KO) of YAP1led to an increase in cell migration, invasion, and metastasis in prostate cancer cells. Microarray analysis showed that the EMT pathway was activated in Yap1-KD cells. ChIP-seq analysis showed that YAP1 target genes are enriched in pathways regulating cell migration. Mass spectrometry analysis identified P4H prolyl hydroxylase in the YAP1 complex and YAP1 was hydroxylated at multiple proline residues. Proline-to-alanine mutations of YAP1 isoform 3 identified proline 174 as a critical residue, and its hydroxylation suppressed cell migration, invasion, and metastasis. KO of P4ha2led to an increase in cell migration and invasion, which was reversed upon Yap1KD. Our study identified a novel regulatory mechanism of YAP1 by which P4HA2-dependent prolyl hydroxylation of YAP1 determines its transcriptional activities and its function in prostate cancer metastasis.

Prostate cancer is a highly heritable disease with large disparities in incidence rates across ancestry populations. We conducted a multiancestry meta-analysis of prostate cancer genome-wide association studies (107,247 cases and 127,006 controls) and identified 86 new genetic risk variants independently associated with prostate cancer risk, bringing the total to 269 known risk variants. The top genetic risk score (GRS) decile was associated with odds ratios that ranged from 5.06 (95% confidence interval (CI), 4.84–5.29) for men of European ancestry to 3.74 (95% CI, 3.36–4.17) for men of African ancestry. Men of African ancestry were estimated to have a mean GRS that was 2.18-times higher (95% CI, 2.14–2.22), and men of East Asian ancestry 0.73-times lower (95% CI, 0.71–0.76), than men of European ancestry. These findings support the role of germline variation contributing to population differences in prostate cancer risk, with the GRS offering an approach for personalized risk prediction.

Background: Polygenic hazard scores (PHS) can identify individuals with increased risk of prostate cancer. We estimated the benefit of additional SNPs on performance of a previously validated PHS (PHS46). Materials and method: 180 SNPs, shown to be previously associated with prostate cancer, were used to develop a PHS model in men with European ancestry. A machine-learning approach, LASSO-regularized Cox regression, was used to select SNPs and to estimate their coefficients in the training set (75,596 men). Performance of the resulting model was evaluated in the testing/validation set (6,411 men) with two metrics: (1) hazard ratios (HRs) and (2) positive predictive value (PPV) of prostate-specific antigen (PSA) testing. HRs were estimated between individuals with PHS in the top 5% to those in the middle 40% (HR95/50), top 20% to bottom 20% (HR80/20), and bottom 20% to middle 40% (HR20/50). PPV was calculated for the top 20% (PPV80) and top 5% (PPV95) of PHS as the fraction of individuals with elevated PSA that were diagnosed with clinically significant prostate cancer on biopsy. Results: 166 SNPs had non-zero coefficients in the Cox model (PHS166). All HR metrics showed significant improvements for PHS166 compared to PHS46: HR95/50 increased from 3.72 to 5.09, HR80/20 increased from 6.12 to 9.45, and HR20/50 decreased from 0.41 to 0.34. By contrast, no significant differences were observed in PPV of PSA testing for clinically significant prostate cancer. Conclusions: Incorporating 120 additional SNPs (PHS166 vs PHS46) significantly improved HRs for prostate cancer, while PPV of PSA testing remained the same.

It is hypothesised that cotargeting the androgen receptor (AR) and paracrine androgen biosynthesis with enzalutamide and abiraterone acetate in metastatic castration-resistant prostate cancer (mCRPC) will dissipate adaptive feedback loops observed with either agent alone.

The recently presented Southwest Oncology Group study of neoadjuvant chemotherapy for patients with muscle-invasive bladder cancer found that three cycles of MVAC prolonged survival (Proc Am Soc Clin Oncol 2001; [...]

To date, anti-CTLA-4 (ipilimumab) or anti-PD-1 (nivolumab) monotherapy has not been demonstrated to be of substantial clinical benefit in patients with prostate cancer. To identify additional immune-inhibitory pathways in the prostate-tumor microenvironment, we evaluated untreated and ipilimumab-treated tumors from patients in a presurgical clinical trial. Levels of the PD-L1 and VISTA inhibitory molecules increased on independent subsets of macrophages in treated tumors. Our data suggest that VISTA represents another compensatory inhibitory pathway in prostate tumors after ipilimumab therapy.

Introduction:An increasing number of basic, translational and clinical studies demonstrate the importance of the protein tyrosine kinase receptor, c-Met, in the progression of prostate cancer. c-Met is overexpressed in primary prostate cancers, further increased in expression in bone metastases and is associated with the development of castrate-resistant disease. Because of its importance as a target, c-Met inhibitors have reached clinical trial for advanced, castrate-resistant prostate cancer.Areas covered:In this review, altered expression of c-Met and hepatocyte growth factor in prostate tumors and the microenvironment and how they contribute to growth and invasion of prostate cancer cells is described. Next, preclinical studies providing the support for use of c-Met inhibitors are discussed. Finally, early promising results from c-Met inhibitors in clinical trial, and future prospects for c-Met inhibitors in the treatment of advanced stage prostate cancer, are discussed.Expert opinion:An emerging theme in treating metastatic prostate cancer is the requirement to target both the epithelial and stromal compartments. Results from clinical trials suggest that inhibitors of c-Met that block stromal-mediated c-Met activation in prostate tumors may be important therapeutic agents in at least a subset of patients with metastatic prostate cancer. However, as many of the inhibitors have multiple targets, the efficacy of targeting c-Met alone remains to be determined.

Purpose: Therapies to target prostate cancer bone metastases have only limited effects.  New treatments are focused on the interaction between cancer cells, bone marrow cells and the bone matrix.  Osteoclasts play an important role in the development of bone tumors caused by prostate cancer.  Since Src kinase has been shown to be necessary for osteoclast function, we hypothesized that dasatinib, a Src family kinase inhibitor, would reduce osteoclast activity and prostate cancer (PC-3) cell-induced osteoclast formation.Experimental Design: We performed in vitro experiments utilizing the Src family kinase inhibitor dasatinib to target osteoclast activation as a means of inhibiting prostate cancer bone metastases. Results: Dasatinib inhibited RANKL-induced osteoclast differentiation of bone marrow-derived monocytes with an EC50 of 7.5 nM.  PC-3 cells, a human prostate cancer cell line, were able to differentiate RAW 264.7 cells, a murine monocytic cell line, into osteoclasts, and dasatinib inhibited this differentiation.  In addition, conditioned medium from PC-3 cell cultures was able to differentiate RAW 264.7 cells into osteoclasts and this too, was inhibited by dasatinib.  Even the lowest concentration of dasatinib, 1.25 nmol, inhibited osteoclast differentiation by 29%.  Moreover, dasatinib inhibited osteoclast activity by 58% as measured by collagen 1 release.Conclusion: Dasatinib inhibits osteoclast differentiation of mouse primary bone marrow-derived monocytes and PC-3 cell-induced osteoclast differentiation.  Dasatinib also inhibits osteoclast degradation activity.   Inhibiting osteoclast differentiation and activity may be an effective targeted therapy in patients with prostate cancer bone metastases.

Bioinformatic analysis of 94 patient-derived xenografts (PDXs), cell lines, and organoids (PCOs) identifies three intrinsic transcriptional subtypes of metastatic castration-resistant prostate cancer: androgen receptor (AR) pathway + prostate cancer (PC) (ARPC), mesenchymal and stem-like PC (MSPC), and neuroendocrine PC (NEPC). A sizable proportion of castration-resistant and metastatic stage PC (M-CRPC) cases are admixtures of ARPC and MSPC. Analysis of clinical datasets and mechanistic studies indicates that MSPC arises from ARPC as a consequence of therapy-induced lineage plasticity. AR blockade with enzalutamide induces (1) transcriptional silencing of TP53and hence dedifferentiation to a hybrid epithelial and mesenchymal and stem-like state and (2) inhibition of BMP signaling, which promotes resistance to AR inhibition. Enzalutamide-tolerant LNCaP cells re-enter the cell cycle in response to neuregulin and generate metastasis in mice. Combined inhibition of HER2/3 and AR or mTORC1 exhibits efficacy in models of ARPC and MSPC or MSPC, respectively. These results define MSPC, trace its origin to therapy-induced lineage plasticity, and reveal its sensitivity to HER2/3 inhibition.

RNA-dependent protein kinase is an interferon-induced, double-stranded (ds), RNA-activated serine/threonine protein kinase involved in the eukaryotic response to viral infection.  While PKR also functions in cellular differentiation, growth control, and apoptosis, its role in human cancer remains poorly understood.  To explore a role for PKR in human cancer, we evaluated PKR expression and function in a series of cancer cell lines from different tumor types. We observed that PKR protein expression is high in various cancer cells and low in normal cells.  Knockdown of PKR protein expression by PKR siRNA induced cell death, indicating a PKR-dependent survival pathway under normal growth conditions.  Inhibition of PKR signaling using a dominant negative adenoviral PKR mutant (Ad-Δ6PKR) also induced cancer cell apoptosis via a mechanism that blocks activation of AKT-mediated survival while simultaneously inducing ER stress. ER stress-mediated apoptosis was evidenced by unregulated expression of phosphorylated JNK (p-JNK), phosphorylated cJun (p-cJun), and caspase-4 and was significantly reduced in cancer cells treated with JNK and caspase-4 inhibitors. We further demonstrated that inhibition of PKR signaling via either siRNA or Ad-Δ6PKR sensitizes cancer cells to etoposide or cisplatin-mediated cell death.  Our results suggest a rationale to develop therapeutic strategies that target PKR signaling in human cancer cells.

This is a phase I/II trial of thalidomide with estramustine and paclitaxel in men with androgen-independent prostate cancer (AIPC) who underwent previous chemotherapy.

Although rarely curative, chemotherapy remains the mainstay of treatment for metastatic urothelial cancer. The role of surgery for metastatic disease is not well established for urothelial cancer, but is sometimes undertaken in the face of persistent or recurrent disease that can be surgically resected.

The objectives of the current study were to determine the maximum tolerated dose and to evaluate the efficacy of gemcitabine given in combination with strontium-89 to patients with androgen independent prostate carcinoma. Patients with androgen-independent prostate carcinoma and painful osteoblastic bone metastases were eligible. On a 12-week course, patients received gemcitabine (600 mg/m² or 800 mg/m²) on Days 1, 8, 15, 43, 50, and 57. A single dose of strontium-89 (55 μCi/kg) was administered on Day 8. Fifteen patients were registered, and all were assessable for response and toxicity. Four patients were treated at Dose Level 1 (gemcitabine 600 mg/m²) without dose-limiting toxicity. Eleven patients received a total of 13 courses at Dose Level 2 (gemcitabine 800 mg/m²). Platelet nadirs of 25,000–50,000 platelets per μL were common at Dose Level 2, and 1 patient had Grade 4 thrombocytopenia that was dose-limiting. Granulocyte nadirs up to < 500 granulocytes per μL occurred in 4 patients at Dose Level 2 and were reversible. There were no responses, as measured by prostate specific antigen concentration, although 6 patients (40%) had stable disease. The authors concluded that 800 mg/m² gemcitabine was the maximum tolerated dose for the combination. The study was terminated on the basis that an overall response rate > than 10% was unlikely. Further study at this dose level and schedule is not warranted. Cancer 2003;97:2988–94. © 2003 American Cancer Society. DOI 10.1002/cncr.11412

Current therapy for advanced prostate cancer is largely based on androgen deprivation and is mostly palliative because all patients eventually relapse with androgen-independent disease. Doxorubicin (Dx), an anthracycline used commonly as a chemotherapeutic agent in relapsed prostate cancer, is a strong inducer of p53 expression and p21CIP1/WAF1 (p21) transactivation. Previous reports suggest that p21 may have a role in the modulation to chemotherapy-induced apoptosis, prostate cancer progression and androgen regulation. In order to investigate if p21 has a pro-survival role in the response of prostate cancer cells to cellular stress, we exposed two androgen-regulated human prostate cancer cell lines (MDA PCa 2b and LNCaP) to Dx and growth factor withdrawal. We then studied expression of p53 and p21, cell-cycle kinetics and apoptosis. We have found that p53 protein accumulated in a dose- and time-dependent manner after Dx treatment, while p21 expression increased over time with low but decreased with high Dx doses. Apoptosis occurred in parallel with p21 down-modulation. Dx treatment of p53 knockout cells demonstrated that p21 induction was strictly p53 dependent. Reduction of p21 levels in prostate cancer cells with an antisense p21 adenovirus resulted in sensitization to Dx and accelerated onset of apoptosis in response to growth factor withdrawal. The evidence presented here also suggests that caspase activation mediates the apoptosis in this system and supports that p21 may modulate the threshold of apoptosis in prostate cancer. These observations may thus provide implications onto the integration of chemotherapy and androgen ablation.

This study was designed to evaluate the efficacy and toxicity of the combination of 5-fluorouracil, interferon-α, and interleukin-2 for patients with metastatic renal cell carcinoma. Previously untreated patients with a Zubrod performance status of ≤2; adequate cardiac, pulmonary, and renal function; and absence of brain metastases were eligible. One course of therapy was 28 days. 5-fluorouracil was administered at a dose of 600 mg/m²/day as a continuous infusions on Days 1-5. Interleukin-2 also was administered as a continuous infusion on Days 1-5 at a dose of 2 million Roche U/m²/day. Interferon-α was given as a daily subcutaneous injection of 4 million U/m²/day. Fifty-five patients were enrolled in the trial and 52 were evaluable for response. All patients experienced fever and flu-like symptoms. Grade 3 or 4 nonhematologic toxic effects included hypertension (48%), dermatitis (12%), stomatitis (11%), and altered mental status (9%). There was one toxic death. Four complete responses and 12 partial responses were observed for a total response rate of 31% (95% confidence interval, 18-46%). The survival of responding patients was significantly better than that of nonresponding patients. The improvement in survival was even more significant when comparing patients with at least stable disease with those who progressed through treatment. The three-drug combination described in this study demonstrates activity. However, it appears to be more toxic than other regimens with similar response rates and cannot be recommended for standard practice. Changing the interleukin-2 route to subcutaneous administration may permit more continuous administration with less toxic effects. Cancer 1997; 80:2128-32. © 1997 American Cancer Society.

We describe 3 patients with metastatic transitional cell carcinoma of the prostate who achieved a complete response with regimens containing cisplatin. Two patients received cyclophosphamide and weekly cisplatin, and 1 was given cyclophosphamide, doxorubicin and cisplatin. All 3 patients had extensive pulmonary metastasis at initiation of chemotherapy. One patient, who also had massive local disease, suffered an isolated brain metastasis 9 months after completion of chemotherapy but he remains in systemic remission 5 months later. Another patient had bilateral brain metastases 3 months after achieving complete remission with chemotherapy, followed 4 months later by systemic relapse. The third patient, who also had bone and bone marrow metastasis, is free of disease 20 months after completion of chemotherapy. In contrast, none of 14 patients with transitional cell carcinoma of the bladder and other sites treated with the same regimens obtained a complete response. Advanced transitional cell carcinoma of the prostate must be recognized promptly, since it is nonresponsive to hormonal manipulation and complete responses have been achieved with cisplatin chemotherapy programs as used in our patients.

In 28 patients with primary clinical stage II testicular carcinoma (retroperitoneal mass of less than 10cm. in diameter) or persistently elevated levels of serum biomarkers after orchiectomy primary chemotherapy was administered followed by selective lymphadenectomy for patients with a persistent retroperitoneal mass. Of the patients 21 were treated with cyclophosphamide, doxorubicin, cisplatin/vinblastine and bleomycin, and 7 who were not candidates for this regimen received less aggressive chemotherapy. All 28 patients were free of disease after a mean followup of 93.6 weeks and a median of 89 weeks (range 28 to 199.5 weeks). No patient who achieved complete remission has had relapse. Of the 28 patients 1 had a seminoma and an elevated alpha-fetoprotein level, 15 had embryonal carcinoma (Dixon-Moore category II) and 12 had teratocarcinomas (DixonMoore category IV). Only 1 of the 15 patients with embryonal carcinoma required surgical exploration for a persistent radiographic abnormality, whereas 6 of the 12 patients with DixonMoore category IV tumors required surgical exploration (p less than 0.0147). This delayed approach did not increase surgical complications.

Adjuvant combination chemotherapy with cyclophosphamide, doxorubicin and cisplatin was administered to 36 patients after cystectomy for bladder cancer. Therapy was tolerated well except for 1 patient who suffered a fatal chemotherapy complication. Indications for adjuvant chemotherapy included vascular invasion of the primary tumor, perivesicular tumor involvement, invasion of adjacent pelvic viscera (vagina and prostate) and nodal metastases.

After curative chemotherapy 58 patients with metastatic germinal tumors and 2 with extragonadal germinal tumors underwent an operation either to confirm a clinical complete response or to remove a residual mass. Biomarker status was converted to negative in all patients. Retroperitoneal lymphadenectomy was done in 22 patients after a complete clinical response was achieved and in 23 after an apparent complete response was achieved except for a residual retroperitoneal mass. Thoracotomy was done for a residual mass in 13 patients, while 2 underwent bilateral thoracotomy. Scarring was found in 25 patients (42 per cent), teratoma in 14 (23 per cent) and active tumor in 17 (28 per cent). One patient with scarring and primary seminoma died of disseminated seminoma, while 1 with primary teratocarcinoma died of disseminated disease, for a false negative rate of 3 per cent. Four patients with a residual mass showed unexpected findings: 2 had granulomas in the lung, 1 had carcinoid of the lung and 1 had retroperitoneal neurofibroma. Thus, there was a 7 per cent incidence of a mass being other than scar, teratoma or residual tumor. There was 1 operative death and 10 deaths of tumor, for an 18 per cent death rate. Of the 17 patients with active tumor 9 responded to salvage chemotherapy with stable complete remission and a minimum followup of 18 months. In addition to the 60 patients the advanced disease in 10 was surgically debulked after failure of chemotherapy and this procedure was followed by salvage chemotherapy. All 10 patients died, with a median survival of 7 months. The lack of responsiveness to chemotherapy was not improved by incomplete removal of tumor.

We retrospectively reviewed the genetic abnormalities detected clinically in 455 men with advanced germ cell tumors referred for chemotherapy. Of the patients 49 had extragonadal and 406 had testicular germ cell tumors. Of 19 patients with mediastinal germ cell tumors 4 (21 per cent, 3 with teratocarcinoma and 1 with endodermal sinus tumor) had Klinefelter’s syndrome. Three of these patients had a 47XXY and 1 had a 48XXYY karyotype. No Klinefelter’s syndrome was observed among 30 consecutive patients with retroperitoneal germ cell tumors or among the 406 with testicular tumors. Karyotypes of 35 consecutive patients with testis cancer without evident congenital abnormalities showed normal chromosomal patterns. We found 2 patients with Down’s syndrome and testicular tumor, for an incidence of 0.5 per cent (probably significant). We also describe 2 cases of nonseminomatous testicular cancer and Marfan’s syndrome (0.5 per cent incidence versus a 5 of 100,000 incidence of Marfan’s syndrome in the general population). Apparently, genetic abnormalities are increased in men with germ cell tumors and we discuss the significance of this association.

Fifty-two patients with advanced seminoma were treated with primary chemotherapy: 44 received cyclophosphamide and weekly cisplatin, and 8 received sequential weekly cisplatin alone. Of the patients treated with chemotherapy alone only 44 achieved a complete remission and 4 were salvaged with further therapy (1 chemotherapy and 3 radiation therapy). These 48 patients (92 per cent) remained free of disease at a followup of 30 to 471 weeks. Six prognostic factors were tested by univariate analysis (chi-square) and only the use of previous chemotherapy predicted for a lower complete remission rate (p equals 0.02). Renal toxicity (greater than 0.4mg. per dl. increase in serum creatinine) occurred in 2 patients (4 per cent). Neurotoxicity occurred in 16 patients (31 per cent). No fatal toxicity occurred. Cyclophosphamide and weekly cisplatin were well tolerated in patients previously treated with radiation therapy and is the treatment of choice for patients with disseminated seminoma.

The effects of bombesin, vasoactive intestinal polypeptide (VIP), and a somatostatin analog (RC-160) on the in vitro invasion of reconstituted basement membrane (Matrigel) by two human prostatic carcinoma cell lines were examined. Aggressively growing PC-3 cells were found to be invasive in this assay in contrast to the relatively indolent LNCaP cells. Bombesin increased penetration of basement membrane by both cell lines. Although VIP had no effect on invasion by PC-3 cells, it enhanced invasion by LNCaP cells in a dose-dependent manner. In agreement with these results, VIP stimulated adenylate cyclase activity only in LNCaP cells. In contrast to bombesin and VIP, RC-160 did not alter invasion by either cell line. Our results suggest that certain neuroendocrine peptides can increase the invasive potential of prostatic carcinoma cells and may thereby contribute to the rapid progression and aggressive clinical course of prostate tumors containing neuroendocrine elements.

The clinical pharmacokinetics of vinblastine administered by continuous 5‐day infusion (3 mg/m2/day) was studied in 12 patients with primary testicular cancer. Serum vinblastine concentrations were determined by radioimmunoassay on serum collected over a 10‐day period. Steady‐state vinblastine concentrations were achieved within 60 to 108 hours (median, 72 hours). Vinblastine pharmacokinetics were analyzed and correlated to hematologic and nonhematologic toxicity. Hematologic toxicity was severe (granulocytopenia of less than 500/μL) in all patients; however, no correlation of vinblastine pharmacokinetics to duration of granulocytopenia or nadir was noted.

Growth stimulation of a variety of cell types by the neurotransmitter serotonin has been reported. We have examined the effects of three serotonin-uptake inhibitors, 6-nitroquipazine, zimelidine and fluoxetine (Prozac, Eli Lilly Co., Indianapolis, Indiana) on human prostate carcinoma cell lines. In vitro, all 3 of these compounds inhibited the proliferation of PC-3, DU-145 and LNCaP cells in a dose-dependent manner. Also, all 3 compounds blocked the uptake of a radiolabeled analog of serotonin by the prostate carcinoma cell lines. The order of potency for inhibition of growth as well as for serotonin uptake was fluoxetine greater than zimelidine greater than 6-nitroquipazine. The growth of subcutaneous, PC-3 xenografts in athymic nude mice was significantly inhibited by fluoxetine. These results implicate biogenic amines such as serotonin in the growth of prostate carcinoma cells and indicate the potential use of serotonin-uptake inhibitors for the treatment of prostate cancer.

We correlated the expression of bcl-2 with accumulation of p53 protein in bone marrow metastases from patients with androgen independent prostate cancer and a history of hormonal ablation therapy. These results were correlated with clinical parameters, including the extent of bone marrow metastases and patient survival.

We conducted a phase II trial to confirm the activity of fixed, low dose γ-interferon in metastatic renal cell carcinoma. A total of 35 patients with metastatic renal cell carcinoma, who had not received prior immunotherapy and who had a Zubrod performance status of 2 or less, was enrolled in this study. Primary tumors were controlled by nephrectomy or embolization before treatment began. γ-Interferon was administered weekly as a subcutaneous injection at a fixed dose of 100 μg. Toxic effects were limited to low grade fever, chills and myalgias within 24 hours of injection. There were no incidences of grade 3 or 4 toxicity. Responses could be evaluated in 34 patients. There were 1 complete and 4 partial responses, for an objective response rate of 15% (95% confidence interval 5 to 32%). Durations of response to date are 21+, 17+, 13+, 9 and 2 months. We conclude that γ-interferon is an active agent for metastatic renal cell carcinoma when administered according to this dose and schedule. The response rate compares favorably with those of α-interferon and interleukin-2, and toxicity is minimal. γ-Interferon has excellent potential for use in combination with other biological or chemotherapeutic agents and in the adjuvant setting.

PurposeThis study was undertaken to establish the pattern of specific p53 gene mutations in prostate cancer within primary tumors and distant metastases.Materials and MethodsWe performed polymerase chain reaction-single-strand conformation polymorphism and sequencing analyses of p53 exons 5-8 in DNA extracted from 22 formalin-fixed, paraffin-embedded tissues from 17 patients. Samples from three patients included specimens from primary and metastatic sites (paired specimens).ResultsG:C-to-A:T transitions were the most common point mutations (64%). Six (55%) of 11 G:C-to-A:T transitions occurred at CpG dinucleotides in five hot-spot codons (175, 245, 248, 273, and 282). Sequencing analysis of the paired samples revealed that two of the three pairs had the same mutation in both. Sequencing analysis of DNA from a different area of one of the primary tumors revealed a different mutation in the p53 gene.ConclusionsOur results suggest that specific p53 mutations participate in the progression of human prostate cancer. These findings support those of others that indicate that the primary cancer is heterogeneous and clonal expansion occurs during the progression of clinically detectable prostate cancer. Our data also imply that p53 mutations at the primary site may be predictive of metastases.

We investigated the activity of combination chemotherapy consisting of paclitaxel, cisplatin and methotrexate in patients with advanced urothelial cancers.

Thirty-eight patients with primary urothelial tumors recurring in the pelvis or nodal presentation were treated with intravenous or intra-arterial cyclophosphamide, doxorubicin and cisplatin chemotherapy. The 38 patients were selected owing to unresectability by local criteria (12 patients) or by virtue of nodal metastases (26 patients). Histologically, the patients either had pure transitional cell carcinoma (29), transformation to a histological subtype of transitional cell carcinoma (7) or pure squamous cell carcinoma (2). An over-all 50 per cent complete remission rate was achieved with an 18 per cent objective pelvic response rate, and 32 per cent failed to respond to chemotherapy. Responses by histological subtype revealed that patients with pure transitional cell carcinoma had a 62 per cent complete remission rate, those with transitional forms had a 14 per cent complete remission rate and none with squamous cell carcinoma responded to chemotherapy. A significant difference in the incidence of responses among patients with transitional carcinoma and those with transition forms was seen (p less than 0.02). Complete remissions were independent of disease site. Nineteen patients achieved a complete remission with a mean duration of 86 weeks and median of 81 weeks (range 33 to 172 weeks). Toxicity of the chemotherapy was moderate with a high incidence of peripheral neuropathy and leukopenic infections. No deaths of chemotherapy were encountered. Patients with locally advanced or metastatic transitional cell carcinoma of the urothelium to lymph nodes can benefit from intravenous and intra-arterial cyclophosphamide, doxorubicin and cisplatin chemotherapy.

A total of 49 patients with metastatic renal cell cancer underwent recombinant interferon-α2a therapy combined with chemotherapy. Before therapy the patients without nephrectomy underwent angioinfarction of the primary renal tumor. Combined treatment included interferon at 5 ×106units per m.2intramuscularly daily, 5-fluorouracil at 750mg./m.2daily by continuous infusion intravenously (days 1 to 5) and mitomycin C at 5mg./m.2per day intravenously (days 1 and 2) repeated every 28 days. Of the patients 17 (35%, 95% confidence interval 22 to 49%) responded, and all 17 had partial remission that lasted a median of 7.1 months (range 4.2 to 20.9+ months). Response rate differed by metastatic sites: lung 46% (18 of 39 patients), lymph nodes 46% (6 of 13), mediastinum 20% (2 of 10) and liver 18% (2 of 11). Grade 3 to 4 toxicity (World Health Organization) included neutropenia (79% of the patients), thrombocytopenia (45%), stomatitis (34%), diarrhea (8%), nausea (18%) and central nervous system disorders (18%). The overall 35% response rate suggests that the combination of interferon-α2a, 5-fluorouracil and mitomycin C is synergistic. Future studies are needed to confirm this finding and to assess the role of mitomycin C.

A total of 14 men with inoperable or metastatic squamous cell carcinoma of the genital tract received methotrexate, bleomycin and cisplatin. In 12 patients the penis was the primary site. Metastases were usually advanced, and 4 patients had ulceration and infection in the inguinal region or perineum secondary to tumor. Two patients had tumor-related hypercalcemia. Of the patients 11 received the 3 drugs intravenously, whereas 3 received methotrexate intravenously, and bleomycin and cisplatin intra-arterially for large unilateral nodal metastasis. Of the 14 patients 10 responded, for a response rate of 72% (95% confidence interval 57 to 92%) and the median response duration was 6 months (range 4 to 24 months). Two patients (14%) who were treated intravenously achieved complete responses lasting 6 and 24+ months. Responses occurred in 3 patients with infection and in both patients with hypercalcemia. The combination of methotrexate, bleomycin and cisplatin has significant activity in patients with advanced squamous cell carcinoma of the male genital tract. This chemotherapy regimen should be evaluated in earlier disease in the adjuvant or neoadjuvant setting.

A total of 33 specimens from 29 patients with residual stable teratoma and mature growing teratoma after chemotherapy was analyzed for clinicopathological and deoxyribonucleic acid (DNA) flow cytometric variables, as well as the presence of proliferative antigen and tumor marker levels in an attempt to explain their clinical behavior. We compared the flow cytometric and histological data of these stable and growing teratomas, and of nonseminomatous germ cell tumors before chemotherapy. The DNA content of residual teratoma did not differ significantly from that of the primary testicular tumors (1.38 versus 1.48). Histological analysis of stable and growing teratomas revealed no significant difference but proliferative cellular nuclear antigen was expressed mainly in the epithelial component of the growing teratoma. α-Fetoprotein, β-human chorionic gonadotropin and carcinoembryonic antigen were elevated in the fluid of 6 excised teratomas, while concomitant serum levels were normal. The aneuploidy and elevated cystic fluid tumor markers confirm the malignant phenotype of post-chemotherapy residual teratomas. Therefore, complete surgical removal is essential despite the benign histological appearance.