Phase Ib study assessing different sequencing regimens of atezolizumab (anti-PD-L1) and sipuleucel-T (SipT)in patients who have asymptomatic or minimally symptomatic metastatic castrate resistant prostate cancer

e17564

Background: Combining an immune checkpoint inhibitor with a tumor vaccine may leverage complementary mechanisms of action for treatment of mCRPC. Atezolizumab, a fully human anti–PD-L1 IgG1 antibody, is an approved treatment option in multiple indications; while SipT, an autologous cellular immunotherapeutic, is approved for treatment of metastatic castrate resistant prostate cancer (mCRPC). We present a phase Ib study evaluating safety, tolerability and objective response rate of atezolizumab + SipT in patients with mCRPC (NCT03024216). Methods: Eligible patients who had asymptomatic or minimally symptomatic progressive mCRPC and met standard criteria for sipuleucel-T were randomized to receive either atezolizumab 1200 mg IV every 3 weeks for 2 doses then SipT IV every 2 weeks for a total of three infusions (Arm 1) or SipT IV every 2 weeks for a total of three infusions followed by atezolizumab 1200 mg IV every 3 weeks for 2 doses (Arm 2). The primary endpoint was safety, while secondary endpoints included objective tumor response (PCWG2 and modified RECISTv1.1 criteria) and comparing systemic immune responses after induction between the arms. Results: As of February 6, 2020, 37 pts (median follow-up 7.4 months, median age 75 yrs [range 53.0–86.0]; median number of previous treatments 4 [range 1-8], 75.7% ECOG PS = 0) were enrolled. Three patients did not complete induction therapy (1 – withdrew consent, 1 developed toxicity, and 1 progressed). There were no grade 5 toxicities attributed to study drugs and grade 4 toxicities were noted in 2 patients, 1 in each arm (Arm 1 bronchitis and Arm 2 hypotension). Eight grade 3 toxicities were noted in arm 1 (hyponatremia, pulmonary embolus x3, bone pain, hypophosphatemia, shock, tooth fracture from a fall), while 4 grade 3 toxicities were noted in arm 2 (anemia, hypertension x 2, pneumonia). None of the grade 3 or 4 SAEs were noted to be irAEs. At 6 months, there were 11 SD (7 in Arm 1 and 4 in Arm 2), 18 PD and 7 unevaluable (3 withdrew from study and 4 have yet to reach 6 month evaluation). At this time, PFS was noted to be 8.2 months in Arm 1 and 5.8 months in Arm 2 (p = 0.054). Conclusions: The safety profile of the combination of atezolizumab with sipuleucel-T appears manageable in a heavily pre-treated population and consistent with those agents administered as monotherapy. Responses were seen but no CR. Immune activation studies may shed light on which sequence is optimal. Clinical trial information: NCT03024216 .

Assessing different sequencing regimens of atezolizumab (atezo) and sipuleucel-T (sipT) in patients who have asymptomatic or minimally symptomatic metastatic castrate-resistant prostate cancer

141

Background: Combining an immune checkpoint inhibitor with a vaccine may leverage complementary mechanisms of action for treatment of mCRPC. We present a randomized study evaluating atezo (anti PD-L1) + sipT in patients (pts) with mCRPC. Methods: Pts who met standard criteria for sipT were randomized to receive (Arm1): atezo 1200 mg IV every 3 weeks for 2 doses then SipT every 2 weeks for a total of 3 infusions (induction) followed by maintenance atezo every 3 weeks until toxicity or loss of clinical benefit or (Arm2) sipT every 2 weeks for a total of 3 infusions followed by atezo 1200 mg IV every 3 weeks for 2 doses (induction) followed by maintenance atezo every 3 weeks until same. The primary endpoint was safety (CTCAE v4.0); secondary endpoints were PFS by PCWG2, objective response (modified RECIST1.1) and systemic immune responses after induction. Results: 37 pts, median age 75 [range 53–86] enrolled; median prior treatments was 4 [range 1-8] and 76% had ECOG PS = 0. Three patients did not complete induction (1 withdrew consent, 1 due to toxicity, and 1 progressed). There were no delays in induction dosing for Arm1 but 9 delays (1 week) for Arm2 (collection failure=6, holiday=2 and other=1). There were no grade 5 toxicities attributed to study drugs. 1 grade 4 toxicity was noted in each arm (Arm 1 bronchitis, Arm 2 hypotension). Eight grade 3 toxicities were noted in arm 1 (hyponatremia, pulmonary embolus x3, bone pain, hypophosphatemia, shock, fall with tooth fracture), while 4 grade 3 toxicities were noted in arm 2 (anemia, hypertension x 2, pneumonia). None of the grade 3 or 4 AEs were immune related. AEs led to discontinuation in 5 patients in Arm1 and 1 patient in Arm2. In Arm1 11 patients were RECIST evaluable at 6 months, with 1 PR (5.8%), 4 SD (23.5%) and 6 PD. In Arm2 13 patients were evaluable, with 1 PR (5.8%), 6 SD (32%) and 6 PD. 10/24 evaluable patients (41.7%) had stable disease at 6 months. Conclusions: The combination of atezo with sipT was safe, AEs consistent with the agents as monotherapy, with no immune related AEs. 2 pts had RECIST PR and 10 had stable disease at 6 months, more than expected with monotherapy. Clinical trial information: 03024216.

A study of intravesical bacillus Calmette-Guerin (BCG) in combination with ALT-803 in patients with non-muscle invasive bladder cancer

TPS545

Background: The current standard of care for patients with high risk NMIBC is a transurethral resection of the bladder tumor (TURBT) or biopsy followed by a 6-week induction course of intravesical BCG treatment and supplementary maintenance instillations every 3 months thereafter (Lamm 2000). While clinical response is significantly improved with BCG treatment, 50% of patients are still expected to recur within the first 12 months (Sfakianos 2014). Thus, the pursuit of novel agents to prevent progression and recurrence of NMIBC remains critical. This clinical trial evaluates the safety and efficacy of ALT-803, an IL-15 superagonist, plus BCG in BCG-naïve NMIBC patients. Methods: Patients with high-risk NMIBC (any high-grade disease, T1, or CIS) who are BCG naïve, will be randomized and enrolled into one of two study arms to be treated with either ALT-803 plus BCG or BCG alone. Patients will receive treatment via a urinary catheter in the bladder, weekly for 6 consecutive weeks during induction. A response assessment will be performed at Week 12: Patients with no disease or low-grade Ta disease will receive a maintenance course of therapy (3 weekly instillations of either ALT-803 plus BCG or BCG alone). Presence of Ta will require a TURBT procedure. Patients with presence of high-grade Ta, CIS or low-grade T1 disease will receive a re-induction course of therapy (6 weekly instillations of either ALT-803 plus BCG or BCG alone). Presence of Ta/T1 will require a TURBT procedure. Patients with high-grade T1 or greater disease (including disease progression) will be considered a treatment failure. Patients with no disease or low-grade Ta disease at months 6, 12, and 18 are eligible for maintenance treatment according to their assigned randomization. Patients with presence of disease greater than low-grade Ta will be considered a treatment failure. The primary endpoint of the study is the proportion of patients receiving ALT-803 plus BCG who are responders by Month 12 or earlier. Responders are defined as patients who experience a complete response (CIS patients) or no disease recurrence (defined as reappearance of high-risk disease). Enrollment is underway. Clinical trial information: NCT02138734.

A multicenter clinical trial of intravesical BCG in combination with ALT-803 in patients with BCG-unresponsive non-muscle invasive bladder cancer

TPS544

Background: BCG unresponsive NMIBC includes patients with persistent high-grade disease or recurrence within 6 months of receiving at least two courses of BCG; or T1 high-grade disease at the first evaluation following BCG induction alone. The recommendation after failing BCG in patients suitable for surgery is cystectomy or for unwilling/unfit patients, salvage chemotherapy or immunotherapy (administered with limited success). This highlights a critical need for novel preservation therapies to facilitate a better quality of life and reduce health-care costs for patients who are unresponsive to BCG (Correa 2015, Dalbagni 2006, Dinney 2013, Kamat 2017). Altor BioScience has initiated a phase II clinical study in BCG unresponsive patients to expand on promising data collected from a compassionate use patient who remains disease free more than 2.5 years after ALT-803 plus BCG treatment for refractory NMIBC (Huang 2017). Methods: This is a Phase II, open-label, single-arm, multicenter study of intravesical BCG plus ALT-803 in patients with BCG unresponsive high grade NMIBC. Group A will enroll patients who have histologically confirmed presence of CIS [with or without Ta or T1 disease]. Group B will enroll patients who have histologically confirmed high-grade Ta or T1 disease (in the absence of CIS). All patients will receive BCG plus ALT-803 weekly for 6 consecutive weeks. A cystoscopy will be performed at Week 12. Patients with no disease or low-grade Ta will receive a maintenance course of therapy (3 weekly instillations of BCG plus ALT-803). Patients with residual CIS and/or high-grade Ta will receive a re-induction course of therapy. Presence of Ta will require a TURBT. Patients with greater than or equal to T1 disease or new CIS will be deemed treatment failures. Patients with a Complete Response (CR) or low-risk disease at Months 6, 9 and 12 are eligible for continued BCG plus ALT-803 maintenance. Patients will be followed for recurrence, progression, and survival. The primary endpoint is to assess complete response (CR; absence of lesions on cystoscopy or negative, for cause, biopsies along with negative urine cytology) of CIS at six months. Enrollment is underway. Clinical trial information: NCT03022825.

Phase Ib trial of ALT-803, an IL-15 superagonist, plus BCG for the treatment of BCG-naïve patients with non-muscle-invasive bladder cancer

510

Background: The current standard of care for patients with high risk NMIBC is a TURBT or biopsy followed by a 6-week induction course of intravesical BCG and supplementary maintenance therapies every 3 months thereafter (Lamm 2000). While clinical response is significantly improved with BCG, 50% of patients are still expected to recur within 12 months ( Sfakianos 2014). The pursuit of novel agents to prevent progression and recurrence of NMIBC remains critical. This phase Ib clinical trial evaluates the safety and tolerability of ALT-803, an IL-15 superagonist, plus BCG in BCG-naïve NMIBC patients. Methods: A dose escalation 3+3 design was employed to evaluate intravesical ALT-803 plus 50 mg BCG in BCG-naïve patients with intermediate or high-risk Ta, T1 or Tis stage NMIBC. Patients received intravesical ALT-803 in conjunction with BCG weekly for 6 consecutive weeks (induction) and then encouraged (but not required) to receive maintenance BCG alone as per standard practices. Patients had a routine cystoscopy and voided urinary cytology (VUC) every 3 months for 2 years to determine response. Negative cystoscopy, VUC and/or biopsy yielded a complete response (CR). No cohort (100, 200 or 400 μg/instillation ALT-803) experienced any dose limiting toxicities. Results: All patients are disease-free (CR) at 24 months; no patients experienced disease recurrence or progression. Adverse events consistent with SoC BCG treatment (hematuria and urinary tract pain) were reported in all cohorts. One patient experienced a grade 3 adverse event of hypertension that resolved the same day. No grade 4 toxicities or DLTs were observed. Clinical trial information: NCT02138734. Conclusions: Intravesical ALT-803 plus BCG treatment is well tolerated in BCG-naïve patients with NMIBC. All patients are disease-free 24 months after treatment with BCG and ALT-803. A randomized phase II trial is currently underway.[Table: see text]

Abstract A05: Angiogenin contributes to bladder cancer tumorigenesis by facilitating p53/DNMT3b-mediated activation of MMP2

Epigenetic-mediated gene activation/silencing plays a crucial role in human tumorigenesis. Eliciting the underlying mechanism behind certain epigenetic changes is essential for understanding tumor biology. An important epigenetic process that is implicated in mammalian development is the methylation of cytosine within the context of a simple dinucleotide site, CpG. Deregulated DNA methylation can be a major driver of pathologic conditions such as neurological and autoimmune diseases, as well as cancers Previous studies in human cancers revealed an unrecognized interplay between Angiogenin (ANG)-MAPK/ERK- matrix metalloproteinase-2 (MMP2) leading to pronounced tumorigenesis. Specifically, we showed that forced ANG expression in a benign human bladder UROtsa cell line induced cellular survival, proliferation, endothelial tube formation and xenograft angiogenesis and growth by mediating the MAPK/ERK-MMP2 axis. Here we provide multiple lines of evidence indicating ANG oncogenic potential and how ANG regulates MMP2 expression.

Here we have shown that deletion and site-directed mutagenesis analysis of the MMP2 promoter demonstrated that the p53-binding site is critical for ANG-induced MMP2 promoter activity. To further determine whether ANG facilitates the recruitment of p53 to its targets in cells, we used a ChIP assay to examine p53 binding to the promoter region of the MMP2 gene in UROtsaEmpty, UROtsaANG, RT112 Scr and RT112 KD-ANG. Overexpression of ANG greatly enriched p53 association with the MMP2 promoter and ANG depletion decreased enrichment of p53 with MMP2 promoter. To further explore the mechanism by which ANG regulates MMP2 expression, we investigated whether ANG is also functionally linked to DNA methylation-based transcriptional repression. First, we quantitatively assessed the methylation status of the MMP2 promoter. Overexpression of ANG was associated with a reduction in methylation status of the MMP2 promoter, which led to increased gene expression of MMP2. The alteration of genome-wide DNA methylation in these cells was then analyzed using Illumina whole genome methylation array. ANG expression was noted to be associated with a change in global DNA methylation levels compared to control cells. Mechanistically, ANG negatively regulated DNA methyltransferase 3b (DNMT3b) enzymatic activity by down-regulating its expression and inhibiting its recruitment to the MMP2 promoter. To further define the role of ANG, p53 and MMP2 in tumorigenesis, we collected 78 fresh bladder cancer samples from bladder cancer patients and extracted DNA and RNA for analysis. Muscle invasive bladder cancer specimens had increased levels of ANG, p53 and MMP2 compared to non-muscle invasive bladder cancer. More importantly, disease free survival was adversely and significantly effected if ANG, p53 and MMP2 were overexpressed.

In this study we demonstrate that ANG is overexpressed in approximately 45% of bladder tumors resulting in overexpression of p53 and MMP2, a reduction in DNMT3b and deep changes in the methylation status genome wide. Such molecular alterations are associated with higher rates of muscle invasive bladder cancers as well as a reduction in disease specific survival, thus attesting to ANG, p53 and MMP2 ability to further risk stratify patients that may require a more aggressive, even personalized, management plan. Therefore, the study provides novel evidence that ANG plays an important role in the promoter activation of the tumor oncogenic gene MMP2, which likely contributes to ANG oncogenic activity.

Citation Format: Rafael Peres, Hideki Furuya, Ian Pagano, Yoshiko Shimizu, Kanani Hokutan, Joanna Gawecka, Charles Joel Rosser. Angiogenin contributes to bladder cancer tumorigenesis by facilitating p53/DNMT3b-mediated activation of MMP2. [abstract]. In: Proceedings of the AACR Special Conference on Chromatin and Epigenetics in Cancer; Sep 24-27, 2015; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2016;76(2 Suppl):Abstract nr A05.

A multiplex immunoassay for the non-invasive detection of bladder cancer

471

Background: Urine based assays that can non-invasively detect bladder cancer (BCa) have the potential to reduce unnecessary and invasive procedures. The purpose of this study was to develop a multiplex immunoassay that can accurately and simultaneously monitor 10 diagnostic urinary protein biomarkers for application as a non-invasive test for BCa detection Methods: A custom electrochemiluminescent (ECL) multiplex assay was constructed (Meso Scale Diagnostics, LLC, Rockville, MD) to detect the following urinary proteins; IL8, MMP9, MMP10, ANG, APOE, SDC1, A1AT, PAI1, CA9 and VEGFA. Voided urine samples from two cohorts (cohort #1 n = 62 and cohort #2 n = 200) were collected prior to cystoscopy and samples were analyzed blinded to the clinical status of the participants. Means (±SD) and receiver operating characteristic (ROC) curve analysis were used to compare assay performance and to assess the diagnostic accuracy of the diagnostic signature. Results: Comparative diagnostic performance analyses revealed an AUROC value of 0.9258 for the multiplex assay and 0.9467 for the combination of the single-target ELISA assays (p = 0.625), so there was no loss of diagnostic utility for the MSD multiplex assay. Analysis of the independent 200-sample cohort using the multiplex assay achieved an overall diagnostic sensitivity of 0.85, specificity of 0.81, positive predictive value 0.82 and negative predictive value 0.84. Conclusions: It is technically feasible to simultaneously monitor complex urinary diagnostic signatures in a single assay without loss of performance. The described protein-based assay has the potential to be developed for the non-invasive detection of BCa.

Phase I trial of ALT-801, a first-in-class T-cell receptor (TCR)-interleukin (IL)-2 fusion molecule, plus gemcitabine (G) for Bacillus Calmette Guerin (BCG)-resistant non-muscle-invasive bladder cancer (NMIBC)

451

Background: Novel agents are necessary to treat BCG-resistant NMIBC to avoid radical cystectomy (RC). This phase I clinical trial evaluated the safety and activity of ALT-801, a recombinant humanized TCR-IL-2 fusion protein in BCG-resistant NMIBC. Methods: This is a Phase I trial using the 3+3 design to evaluate intravenous (IV) ALT-801 plus IV G 1000 mg/m2 in BCG-resistant high-risk NMIBC patients (pts) defined as high grade Ta, T1 or carcinoma in situ, size > 4 cm or multi-focal tumors. BCG-intolerant pts, those who refused or were unfit to undergo RC were also eligible. Initially, patients received ALT-801 monotherapy; an amendment added G. Pts received induction of 2 cycles, with a 13-day rest between cycles. Each cycle consisted of 4 doses of ALT-801 on Day 3, Day 5, Day 8, and Day 15 and 2 doses of G, one each on Day 1 and Day 8. Pts who have a biopsy-proven complete response (CR) after induction received one maintenance cycle and underwent response assessment. The initial dose of ALT-801 was 0.08 mg/kg with 2 step-down doses allowed if dose limiting toxicities (DLTs)- 0.06 mg/kg and 0.04 mg/kg. Results: 2 pts in cohort one received ALT-801 alone at 0.08 mg/kg per dose, a 3rd pt received G and ALT-801 at 0.08 mg/kg per dose. Grade ≥ 3 hepatotoxicity in the 3rd patient led to a step-down to 0.06 mg/kg dose. One pt in the 0.06 mg/kg dose experienced a DLT (Grade ≥ 3 hepatotoxicity) and the cohort was expanded to 6 pts with no further DLTs. Other attributed adverse events were: anorexia, pruritus, rash, edema, fatigue, chills. For the 0.06 mg/kg ALT-801 + G regimen, 6 pts received up to 2 cycles of induction and 4 pts received the maintenance cycle. All pts have completed therapy without further DLTs. CR was observed in 3 pts, which was durable in 2 pts lasting ≥ 18 months. Preliminarily immune studies have shown transient IFN-γ and IL-6 but not TNF-α and IL-10 induction after ALT-801 dosing. Conclusions: ALT-801 plus gemcitabine was feasible in BCG-resistant NMIBC and demonstrated immune responses and potential durable clinical activity. Further evaluation in expansion cohorts in a phase Ib/II trial is planned. Clinical trial information: NCT01625260.

Phase Ib trial of ALT-803, an IL-15 superagonist, plus Bacillus Calmette Guerin (BCG) for the treatment of patients with BCG-naïve non-muscle-invasive bladder cancer (NMIBC)

470

Background: Novel agents are necessary to treat NMIBC to avoid recurrence and progression. This phase Ib clinical trial evaluated the safety and toleraibility of ALT-803, an IL-15 superagonist, plus BCG in patients with BCG-naïve NMIBC. Methods: This is a Phase Ib trial using the 3+3 design to evaluate intravesical ALT-803 plus BCG 50 mg in BCG-naïve NMIBC patients, who would normally be eligible for intravesical BCG alone. The initial dose of ALT-803 was 100 μg/instillation with 2 dose-escalations allowed (200 μg/instillation and 400 μg/instillation) if dose limiting toxicities (DLTs) were not evident. Patients received intravesical ALT-803 in conjunction with BCG weekly for 6 consecutive weeks (Induction Phase). Patients then had routine follow-up with cystoscopy and voided urinary cytology (VUC) every 3 months for 2 years equating to confirmatory response assessment. Negative cystoscopy, VUC and/or biopsy yielded a complete response (CR). When appropriate for high-risk patients, physicians and patients were encouraged to receive maintenance BCG alone as per common practice patterns. Results: No patient in 100 μg/instillation of ALT-803/BCG and 200 μg/instillation of ALT-803/BCG reported an AE. One patient in 400 μg/instillation/BCG cohort developed a urinary tract infection requiring delay of intravesical treatment by 1 week. No grade 3/4 toxicities were noted. All patients have completed therapy without DLTs. To date, 4 patients have 12 month follow-up and are CR. The remaining 5 patients have no evidence of disease. However, follow-ups are currently approximately 3 months. Corollary immune studies are still pending. Conclusions: Intravesical ALT-803 plus BCG was safe and tolerable in patients with BCG-naive NMIBC. Further evaluation in expansion cohorts in a phase II trial is currently underway. Clinical trial information: NCT02138734.

Angiogenin promotes tumoral growth and angiogenesis by regulating matrix metallopeptidase-2 expression via the ERK1/2 pathway

Tumor angiogenesis is essential for tumor growth and metastasis and is dependent on key angiogenic factors. Angiogenin (ANG), a 14.2-kDa polypeptide member of the RNase A superfamily, is an angiogenic protein that has been reported to be upregulated and associated with poor prognosis in some human cancers. The mechanisms through which aberrant ANG levels promote specific steps in tumor progression are unknown. Here, we show that ANG expression in human tissues is strongly correlated with an invasive cancer phenotype. We also show that ANG induces cellular survival, proliferation, endothelial tube formation and xenograft angiogenesis and growth. Novel mechanistic investigations revealed that ANG expression stimulated matrix metallopeptidase-2 (MMP2) expression through the phosphorylation of ERK1/2. Targeting ANG in vivo with N65828, a small-molecule inhibitor of the ribonucleolytic activity of human ANG, resulted in the diminution of xenograft tumoral growth through the inhibition of angiogenesis. Our findings support an unrecognized interplay between ANG, ERK1/2 and MMP2 that can impact tumor growth and progression. The targeting of ANG and associated factors could provide a novel strategy to inhibit tumor establishment and growth.

A multi-analyte assay for the noninvasive detection of bladder cancer

306

Background: Accurate urinary assays for bladder cancer (BCa) detection would benefit both patients and healthcare systems. Through genomic and proteomic profiling of urine components, we have previously identified a panel of biomarkers that can outperform current urine-based biomarkers for the non-invasive detection of BCa. Herein, we report the diagnostic utility of various multivariate combinations of these biomarkers. Methods: We performed a case-controlled validation study in which voided urines from 550 patients (220 tumor bearing subjects) were analyzed. The urinary concentrations of 14 biomarkers (IL-8, MMP-9,MMP-10, SDC1,CCL18, PAI-1, CD44, VEGF, ANG, CA9,A1AT, OPN, PTX3, and APOE) were assessed by enzyme-linked immunosorbent assay (ELISA). Diagnostic performance of each biomarker and multivariate models were compared using receiver operating characteristic curves and the chi-square test. Results: An 3-biomarker model (CA9, PAI-1 and IL-8) achieved the most accurate BCa diagnosis (sensitivity 90%, specificity 88%). These data show that a multivariate urine-based assay can markedly improve the accuracy of non-invasive BCa detection. Conclusions: Further validation studies are under way to investigate the clinical utility of this panel of biomarkers for BCa diagnosis and disease monitoring.

Phase I/II clinical trial of ALT-801, a T-cell receptor/IL-2 fusion protein, plus gemcitabine and cisplatin in urothelial cancer

271

Background: ALT-801, a T-cell receptor/IL-2 fusion protein, activates NK and CD4+ lymphocytes to secrete IFN-gamma which re-polarizes tumor associated macrophages from M1 to M2 in various murine tumor models. CD8+ memory cells also acquire an innate immune phenotype and become expanded upon ALT-801 activation. Via this novel mechanism, ALT-801 mounted effective immune responses and maintained immunological memory against urothelial cancer in these models. Pretreatment chemotherapy eliminated myeloid-derived suppressive cells, potentiating the anti-tumor effects of ALT-801 (Wong, unpublished data). Previous clinical studies with ALT-801 (advanced malignancy; Fishman 2011 CCR 17:7765) and ALT-801 + cisplatin (melanoma; NCT01029873) showed anti-tumor activity in these settings. Methods: We evaluated co-administration of gemcitabine [G] (1000 mg/m2/dose, day 1 and 8) and cisplatin [C] (70 mg/m2/dose, day 1) with ALT-801 (escalating doses; days 3, 5, 8, 10) for three 21-day cycles, in patients with metastatic urothelial cancer. Those with at least stable disease after 3 courses could receive 4 additional weekly doses of ALT-801 alone. ALT-801 doses were planned at 0.04 to 0.12 mg/kg/dose in 5 cohorts with a 3+3 escalation design. Results: The dose-escalation is completed, with a recommended dose of ALT-801 of 0.06 mg/kg/dose. The best objective response rate (ORR, RECIST v1.1) among 5 chemo-naïve subjects was 100% (2 CR, 3 PR) and among 5 previously treated patients 60% (1 CR, 2 PR), for an overall total of 80% (3 CR, 5 PR, 1 SD, 1 PD). One of 2 patients who underwent radical cystectomy was confirmed pathologically free of tumor. Responding lesions included bulky and extensive liver and pulmonary metastases, and adenopathy. ALT-801 at the 0.06 mg/kg/dose level in this combination was adequately-tolerated. Grade 3/4 toxicities including neutropenia, thrombocytopenia and lymphopenia, appear consistent with known G, C, and ALT-801 effects. Conclusions: ALT-801 is a novel and potentially active immunotherapy for urothelial cancer. More patients are in treatment on the open phase 2 expansion portion of the study (NCT01326871), and updated interim results are anticipated (CA097550). Clinical trial information: NCT01326871.

Induction of endothelial proliferation and angiogenesis through activating the ERK1/2/EGF pathway mediate by CXC chemokine receptor 2 by chemokine (C-X-C motif) ligand 1

138

Background: Endothelial cell growth and proliferation are critical for tumoral angiogenesis. We report here that blockade of Chemokine (C-X-C motif) ligand 1 (CXCL1) results in reduction of human endothelial cell proliferation and its ability to induce angiogenesis. Methods: Two human endothelial cell lines, HUVEC and HDMEC, were used in the in vitro assays. Proliferation assay and matrigel tube formation assay were performed to test the inhibitory effect of anti-CXCL antibody on the activity of endothelial cells in vitro. Matrigel plug assay in nude mice was performed to test the in vivo angiogenic activity of CXCL1. Results: CXCL1 interacts with its receptor CXC chemokine Receptor 2 and induces endothelial cell proliferation, whereas blockade of CXCL1 is associated with reduction in cellular proliferation through a decrease in levels of cyclin D and cdk4 and inhibition of angiogenesis through EGF and ERK 1/2. Targeting CXCL1 inhibits neoangiogenesis but has no effect on disrupting established vasculature. Furthermore targeting CXCL1 is associated with reduction in migration of human endothelial cells in an in vitro model. Additionally, neutralizing antibody against CXCL1 in a xenograft angiogenesis model resulted in inhibition of angiogenesis. Conclusions: CXCL1-induced regulation of angiogenesis has not been studied extensively in human cancers, thus these findings illustrate a novel contribution of CXCL1 interactions in pathological angiogenesis. Therefore, the ability to selectively modulate CXCL1, specifically in tumoral angiogenesis, may promote the development of novel oncologic therapeutic strategies.

Tumor burden reduction in an orthotopic non-muscle-invasive bladder cancer model using IL-15 analogue (ALT-803) targeting T regulatory cells

298

Background: A recent NCI review listed IL-15 as the most promising product candidate among twelve immunotherapy drugs that could potentially cure cancer. Preclinical studies using ALT-803 (mutated IL-15 analogue combined with IL-15Rα-Fc fusion) have shown promising results for obtaining prolonged drug half-life and stimulating CD8+ T cells and NK cells. Based on these results, we hypothesized that the administration of ALT-803 will generate an immunologic response which will reduce tumor burden in a rodent carcinogen induced orthotopic non muscle invasive bladder cancer model (NMIBC). Methods: We tested intravesical ALT-803 alone and ALT-803 in combination with Bacillus Calmette-Guérin (BCG) in a rodent carcinogen induced orthotopic NMIBC model. Rats were anesthetized then a 22-gauge Teflon transurethral catheter was placed in the bladder and urine completely drained from the bladder. Next, the saline (negative control), ALT-803 (experimental agent) or BCG (positive control) therapy was delivered by transurethral instillation and allowed to dwell in the bladder for 1 hr by occlusion of the urethra with a purse string suture. The intravesical therapy was administered weekly for a total of six weeks to mimic intravesical BCG therapy in humans. Results: Herein we demonstrate that ALT-803 was safe and well tolerated alone or in combination with BCG. Furthermore, ALT-803 alone reduced tumor burden by 23% whereas BCG alone reduced tumor burden by 11% compared to control. The combination of ALT-803 and BCG reduced tumor burden by 30% compared to control. Tumoral responses of the combinational treatment were associated with 76% and 80% reduction in angiogenesis and proliferation, respectively, whereas combinational therapy was associated with a 7.7-fold increase in apoptotic index compared to control. Immune monitoring suggested that the antitumor response was linked to the activation of CD8+ cells and NK cells. Conclusions: The enhanced therapeutic index provided by ALT-803 plus BCG therefore provides a powerful justification for the development of this agent for future clinical trials in subjects with non-muscle invasive bladder cancer.

Discovery of molecular biomarker signatures for the detection of bladder cancer

302

Background: Bladder cancer (BCa) is among the five most common malignancies world-wide, and due to high rates of recurrence, one of the most prevalent. Improvements in non-invasive urine-based assays to detect BCa would benefit both patients and healthcare systems. In this study, the goal was to identify urothelial cell transcriptomic signatures associated with BCa. Methods: Gene expression profiling (Affymetrix U133 Plus 2.0 arrays) was applied to exfoliated urothelia obtained from a cohort of 92 subjects with known bladder disease status. Computational analyses identified candidate biomarkers of BCa and an optimal predictive model was derived. Selected targets from the profiling analyses were monitored in an independent cohort of 81 subjects using quantitative real-time PCR (RT-PCR). Results: Data analysis identified 52 genes associated with BCa (p≤0.001), and gene models that optimally predicted class label were derived. RT-PCR analysis of 48 selected targets in an independent cohort identified a 14-gene diagnostic signature that predicted the presence of BCa with a specificity of 100% at 90% sensitivity. Conclusions: Exfoliated urothelia sampling provides a robust analyte for the evaluation of patients with suspected BCa. The refinement and validation of the multi-gene urothelial cell signatures identified in this preliminary study may lead to accurate, non-invasive assays for the detection of BCa. The development of an accurate, non-invasive BCa detection assay would benefit both the patient and healthcare systems through better detection, monitoring and control of disease.

Molecular diagnostic trends in urological cancer: biomarkers for non-invasive diagnosis

The early detection of urological cancers is pivotal for successful patient treatment and management. The development of molecular assays that can diagnose disease accurately, or that can augment current methods of evaluation, would be a significant advance. Ideally, such molecular assays would be applicable to non-invasively obtained body fluids, enabling not only diagnosis of at risk patients, but also asymptomatic screening, monitoring disease recurrence and response to treatment. The advent of advanced proteomics and genomics technologies and associated bioinformatics development is bringing these goals into focus. In this article we will discuss the promise of biomarkers in urinalysis for the detection and clinical evaluation of the major urological cancers, including bladder, kidney and prostate. The development of urine-based tests to detect urological cancers would be of tremendous benefit to both patients and the healthcare system.

Early outcome results of a phase I/II study for an IL-2/T-cell receptor fusion protein in combination with gemcitabine and cisplatin (GC) in patients with locally advanced or metastatic urothelial cancer

e15010

Background: ALT-801 is a human IL-2/single-chain T-cell receptor fusion protein previously tested in a phase 1 in patients with advanced malignancy (Fishman 2011 CCR 17:7765) (CA097550). In various murine models, ALT-801 demonstrated potent activity against syngeneic and xenograft UC, suggesting sensitivity of this disease to IL-2 based immunotherapy (Wong, unpubl. data.). Although UC are sensitive to platinum-based chemotherapy, combinations such as gemcitabine (G) + cisplatin (C) are associated with CR rates of around 15%, and limited durability of responses with limited effects of retreatment. Methods: We report here initial efficacy results of co-administration of G (1000 mg/m2/dose, d 1 & 8), C (70 mg/m2/dose, d 1) and ALT-801 (escalating doses, d 3, 5, 8, 10) on a 21 day schedule, for 3 cycles, in patients with UC that was locally advanced, or metastatic, for whom GC chemotherapy would be considered. ALT-801 planned doses are 0.04 to 0.12 mg/kg/dose in 5 dose cohorts with a 3+3 escalation design. Subjects with at least stable disease after 3 courses may receive 4 additional weekly doses of ALT-801 alone. Results: To date, three Stage IV UC patients (1F, 2M; 59-63 yrs; 2 patients had predominantly nodal metastases and one patient liver metastases) completed treatment with 0.04 mg/kg ALT-801+GC. Two had previously undergone radical cystectomy and had then later failed following GC treatment. Grade 3/4 toxicities observed include neutropenia (2), thrombocytopenia (2), leukopenia (1), lymphopenia (1) and anemia (1), consistent with GC and ALT-801 known pharmacodynamic effects. All 3 had radiological CRs by week 13. One patient underwent radical cystectomy had a pCR. The next (0.06 mg/kg/dose) cohort has started treatment. A phase II expansion cohort is planned at the MTD. Conclusions: The early response pattern is encouraging in that ALT-801 may be a novel, active immunotherapy for UC. NCT01326871

Utility of serial urinalyses and urinary cytology in the evaluation of patients with microscopic haematuria

BACKGROUND

Serial urinalyses have been advocated when haematuria is suspected.

OBJECTIVE

To determine the utility of serial urinalyses and urinary cytology in patients presenting for evaluation of microscopic haematuria.

METHODS

Eighty-five patients with the diagnosis of microscopic haematuria were evaluated at a tertiary-care hospital. All patients had a comprehensive urologic evaluation. Clinic and hospital records were reviewed for key factors (e.g., demographic, pathology, radiologic findings and operative findings).

RESULTS

One hundred ninety total urinalyses were reviewed. Eighty-eight (46%) urinalyses were classified as normal, 87 (46%) as haematuria (> 3 RBC/hpf), and 15 (8%) as pyuria/ bacteriuria. The initial urinalysis detected haematuria in 95% of the patients. The addition of the second and third urinalyses detected haematuria in the remaining 5% of the patients with haematuria. Aetiologic factors for microscopic haematuria include urolithiasis 15 (18%), infection 9 (11%) and bladder lesion/tumor 6 (7%). In this setting of microscopic haematuria, urinary cytology was not able to detect any of the five documented bladder tumors. Fifty-seven percent of patients had a negative haematuria evaluation.

CONCLUSION

In the evaluation of the patient with microscopic haematuria, serial urinalyses may have a low yield. Further prospective studies are needed to further evaluate serial urinalyses in this cohort.

Exogenous mycoplasmal p37 protein alters gene expression, growth and morphology of prostate cancer cells

We previously showed that the Mycoplasma hyorhinis-encoded protein p37 can promote invasion of cancer cells in a dose-dependent manner, an effect that was blocked by monoclonal antibodies specific for p37. In this study, we further elucidated changes in growth, morphology and gene expression in prostate cancer cell lines when treated with exogenous p37 protein. Incubation with recombinant p37 caused significant nuclear enlargement, denoting active, anaplastic cells and increased the migratory potential of both PC-3 and DU145 cells. Microarray analysis of p37-treated and untreated cells identified eight gene expression clusters that could be broadly classified into three basic patterns. These were an increase in both cell lines, a decrease in either cell line or a cell line-specific differential trend. The most represented functional gene categories included cell cycle, signal transduction and metabolic factors. Taken together, these observations suggest that p37 potentiates the aggressiveness of prostate cancer and thus molecular events triggered by p37 maybe target for therapy.

Gene therapy for superficial bladder cancer

In this review, the basics of gene therapy and the strategies to increase the therapeutic effect of gene therapy for superficial bladder cancer are discussed. Strategies considered in detail are modification of the structure of vectors, modification of the promoters of viral vectors and the timing and route of vector administration. Although all of these modifications have shown some degree of improvement for gene transfer, the use of polyamides intravesically in conjunction with an adenoviral system shows the most promise and the greatest potential to supplement or even replace the current treatment modalities for superficial bladder cancer.

Are coagulation studies necessary before percutaneous nephrostomy?

PURPOSE

Performance of coagulation studies for patients undergoing percutaneous nephrostomy (PCN) has been advocated by some investigators. We performed a retrospective study to assess this practice.

MATERIALS AND METHODS

The medical records of 180 patients subjected to PCN for various reasons between October 1991 and July 1998 were reviewed. This represents a subset of patients in whom PCN was performed by an experienced interventional radiologist at our institution. Patients were excluded if they had a history of active liver disease, hematologic or bleeding disorder, current use of heparin or warfarin, or platelet count <100,000. The remaining 160 patients were separated into two groups. Group 1 consisted of 153 patients with a normal prothrombin time (PT) and partial thromboplastin time (PTT). Group 2 comprised 7 patients with an abnormal PT or PTT. Demographic and laboratory data including PT, PTT, complete blood, and platelet counts were analyzed to determine if a hemorrhagic complication could be predicted by an abnormal PT or PTT.

RESULTS

In group 1 the mean PT was 12.2 seconds and the mean PTT was 25.0 seconds; in group 2 the mean PT was 13.9 seconds and the mean PTT was 30.3 seconds. The hemorrhagic complication rates were not statistically different between the two patient cohorts (p = .203). Demographic and standard laboratory data were not predictive of abnormal coagulation parameters.

CONCLUSIONS

Screening coagulation studies are unnecessary in the standard patient subjected to PCN.

Thoracoabdominal radical nephrectomy: is a postoperative thoracostomy tube necessary?

OBJECTIVES

To report our results of patients undergoing thoracoabdominal radical nephrectomy without intraoperative placement of a thoracostomy tube. It has been routine in our hospital to not place a thoracostomy tube in patients undergoing thoracoabdominal radical nephrectomy since 1988.

METHODS

We conducted a retrospective review of 47 thoracoabdominal radical nephrectomies performed from January 1988 through November 1998 at our institution. Of the 47 patients, 39 did not have a thoracostomy tube placed intraoperatively; the other 8 patients did. The development of all postoperative complications, length of hospital stay, and hospital charges were noted.

RESULTS

No postoperative mortality was noted in our study. Of the 47 patients in the study, 20 patients had a total of 29 complications. The overall number of complications was not increased in the group without a thoracostomy tube compared with the group with a thoracostomy tube (P = 0.104). No patient treated without a thoracostomy tube required subsequent placement of a tube for persistent pneumothorax. The mean length of hospital stay in patients with a thoracostomy tube after radical nephrectomy was 9.14 +/- 2.65 days; in patients without a thoracostomy tube, the mean length of stay was 7.07 +/- 3.97 days (P = 0.071).

CONCLUSIONS

In patients without parietal pleural injury, thoracoabdominal radical nephrectomy without the placement of a thoracostomy tube can be performed safely and effectively, with a low risk of postoperative complications and a decrease in the overall hospital stay and hospital charges.

Is there a learning curve in diagnosing urolithiasis with noncontrast helical computed tomography?

OBJECTIVE

To report one department's experience with helical computed tomographic (HCT) evaluation of patients with suspected renal colic to diagnose ureteral calculi; to determine whether there is a learning curve in performing HCT in this context; and to determine whether HCT for the evaluation of renal colic exposes patients to more radiation than the standard intravenous pyelography (IVP) combined with nephrotomography.

METHODS

All patients presenting to the emergency department with flank or abdominal pain were evaluated with nonreformatted noncontrast HCT. To determine changes in diagnostic accuracy, patients were divided into 2 groups: those evaluated between September 1996 and January 1997 (group 1, 67 patients), and those seen from February to June 1997 (group 2, 53 patients). A radiation exposure study was performed using phantoms, and radiation exposure for HCT, IVP and nephrotomography was measured.

RESULTS

Review of HCT scans to diagnose ureteral calculi had a sensitivity of 91.7%, specificity of 82.6%, and accuracy of 87.2% in group 1, and a sensitivity of 95.5%, specificity of 86.7%, and accuracy of 91.9% in group 2. Patients undergoing IVP with nephrotomography were exposed to an effective dose equivalent of 343 mrem (dSv) (for men) and 664 mrem (for women). The effective dose equivalent for an HCT scan was 180 mrem.

CONCLUSION

HCT offers excellent, rapid diagnostic accuracy without the need for intravenous contrast medium and with a lower radiation exposure level than IVP in evaluating patients with acute flank pain. There is a small but real learning curve in evaluating patients with acute flank pain with HCT.

Metastatic small cell carcinoma to the testis

Testicular neoplasms comprise 1% of all malignancies in men, with less than 3% of these malignancies due to metastatic disease. We report a case of a 51-year-old man with a history of left pneumonectomy done 2 years earlier for small cell carcinoma of the lung; the patient came to his primary care physician for routine follow-up. Physical examination was significant for a left testicular mass, which on final pathology was diagnosed as metastatic small cell carcinoma.

Metastatic adenocarcinoma of the pancreas to the testicle: a case report

We report a 58-year-old man who presented with a 1-month history of left testicular pain and swelling that was eventually diagnosed as metastatic adenocarcinoma from the pancreas. Currently, there are only three accounts in the English literature of metastatic pancreatic carcinoma to the testis.

Detection of high-grade prostatic intraepithelial neoplasia with the five-region biopsy technique

OBJECTIVES

To assess the ability of the five-region biopsy technique compared with the traditional sextant biopsy technique to detect high-grade prostatic intraepithelial neoplasia (PIN) in patients with an abnormal digital rectal examination or elevated prostate-specific antigen, or both, by a retrospective study.

METHODS

We conducted a retrospective review of 50 consecutive patients diagnosed with PIN at our institution from January 1 990 to May 1998. Of the 50 patients, 26 patients were diagnosed with high-grade PIN. The reasons for the initial prostate biopsy were elevated prostate-specific antigen in 15 patients, abnormal digital rectal examination in 1 patient, and combined abnormalities in 10 patients. These patients underwent transrectal ultrasound-guided needle biopsy of the prostate using the five-region biopsy technique. Biopsy findings from regions 1, 3, and 5 (additional five-region biopsies) were compared with those of regions 2 and 4 (traditional sextant biopsies).

RESULTS

Of the 26 patients, PIN was detected in the sextant regions in only 14 patients (53%). However, by using the five-region biopsy technique, an additional 1 2 patients (47%) were diagnosed with PIN (P <0.05). Twenty-four patients underwent repeated five-region biopsies. Eight (33%) of the 24 patients were found to have prostate cancer. Of the eight patients with cancer, 5 of the cancers were found with the five-region biopsy technique.

CONCLUSIONS

In this study, the five-region method of prostate biopsy significantly increased the diagnosis of PIN compared with the traditional sextant method of biopsy. Furthermore, 33% of patients diagnosed with high-grade PIN on the initial biopsies were found to have prostate cancer on subsequent five-region biopsies.

Urinary tract infections in the critically ill patient with a urinary catheter

BACKGROUND

The diagnosis of urosepsis should be entertained each time a patient has a febrile episode. Urosepsis carries with it a mortality rate of 25% to 60%. We determined the incidence and risk factors of urosepsis in the catheterized critically ill patient.

MATERIALS AND METHODS

The charts of 142 subjects admitted from November 1994 to November 1995 to the trauma intensive care units at our institution with a urinary catheter were reviewed. Urosepsis was defined as (1) positive blood and urine cultures that correlated; (2) positive urine cultures with radiologic evidence of obstructive uropathy or infection; or (3) positive urine cultures and all other cultures negative to be eligible for the urosepsis group.

RESULTS

Of the 126 patients evaluated for sepsis, 20 (15.8%) were diagnosed with urosepsis. Multivariant analysis demonstrated that the incidence of urosepsis was correlated with the following: age >60 years, extended length of stay in the intensive care unit and/or hospital, and duration of urinary catheterization. All 20 patients who developed urosepsis had a positive urinalysis and a positive urine culture (sensitivity 100%). However, urinalyses were positive in another 63 patients who did not have urosepsis (specificity 24.1%), and urine cultures were positive in 31 patients who did not have urosepsis (specificity 70.8%).

CONCLUSION

We found a 15.8% incidence of urosepsis in our patient population. Urosepsis was more likely to occur in patients over 60 years of age, patients with extended length of stay in the intensive care unit or in the hospital in general, and patients with an extended duration of urinary catheterization.