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Purpose: Sabizabulin, an oral cytoskeleton disruptor, was tested in a phase Ib/II clinical study in men with metastatic castration-resistant prostate cancer (mCRPC). Patients and Methods: The phase Ib portion utilized a 3+3 design with escalating daily oral doses of 4.5–81 mg and increasing schedule in 39 patients with mCRPC treated with one or more androgen receptor–targeting agents. Prior taxane chemotherapy was allowed. The phase II portion tested a daily dose of 63 mg in 41 patients with no prior chemotherapy. Efficacy was assessed using PCWG3 and RECIST 1.1 criteria. Results: The MTD was not defined in the phase Ib and the recommended phase II dose was set at 63 mg/day. The most common adverse events (>10% frequency) at the 63 mg oral daily dosing (combined phase Ib/II data) were predominantly grade 1–2 events. Grade ≥3 events included diarrhea (7.4%), fatigue (5.6%), and alanine aminotransferase/aspartate aminotransferase elevations (5.6% and 3.7%, respectively). Neurotoxicity and neutropenia were not observed. Preliminary efficacy data in patients treated with ≥1 continuous cycle of 63 mg or higher included objective response rate in 6 of 29 (20.7%) patients with measurable disease (1 complete, 5 partial) and 14 of 48 (29.2%) patients had PSA declines. The Kaplan–Meier median radiographic progression-free survival was estimated to be 11.4 months (n = 55). Durable responses lasting >2.75 years were observed. Conclusions: This clinical trial demonstrated that chronic oral daily dosing of sabizabulin has a favorable safety profile with preliminary antitumor activity. These data support the ongoing phase III VERACITY trial of sabizabulin in men with mCRPC.

Purpose: A blood test to detect colon cancer at a preventable stage would represent a major advancement. We have previously identified colon cancer–specific markers using focused proteomics analysis of nuclear structural proteins. Two of these markers, colon cancer–specific antigen (CCSA)-3 and CCSA-4, have been developed into blood-based markers that are able to distinguish individuals with colorectal cancer from those without. CCSA-2 is a distinct novel colon cancer marker identified using focused proteomics.Experimental Design: Using an indirect ELISA on serum samples obtained from two institutions, we evaluated CCSA-2 as a serum-based colon cancer marker. A total of 111 serum samples from individuals who underwent colonoscopy and were subsequently diagnosed as either being normal or having hyperplastic polyps, nonadvanced adenomas, advanced adenomas, and colorectal cancer were evaluated. A diverse control population that consisted of 125 serum samples was also included in this study.Results: Receiver operating characteristic analyses were used to measure the sensitivity and specificity of CCSA-2. CCSA-2 at a cutoff of 10.8 μg/mL has overall specificity of 78.4% [95% confidence interval (95% CI), 67.3-87.1%] and sensitivity of 97.3% (95% CI, 85.8-99.5%) in separating individuals with advanced adenomas and colorectal cancer from normal, hyperplastic, and nonadvanced adenoma populations. The receiver operating characteristic curve for CCSA-2 has an area under the curve of 0.90 (95% CI, 0.83-0.95).Conclusion: Our initial study shows that CCSA-2 is a potential serum-based marker for colon cancer detection with high sensitivity and specificity.

Supplementary Table from A Phase Ib/II Study of Sabizabulin, a Novel Oral Cytoskeleton Disruptor, in Men with Metastatic Castration-resistant Prostate Cancer with Progression on an Androgen Receptor–targeting Agent

Suppl. Methods

Purpose:Sabizabulin, an oral cytoskeleton disruptor, was tested in a phase Ib/II clinical study in men with metastatic castration-resistant prostate cancer (mCRPC).Patients and Methods:The phase Ib portion utilized a 3+3 design with escalating daily oral doses of 4.5–81 mg and increasing schedule in 39 patients with mCRPC treated with one or more androgen receptor–targeting agents. Prior taxane chemotherapy was allowed. The phase II portion tested a daily dose of 63 mg in 41 patients with no prior chemotherapy. Efficacy was assessed using PCWG3 and RECIST 1.1 criteria.Results:The MTD was not defined in the phase Ib and the recommended phase II dose was set at 63 mg/day. The most common adverse events (>10% frequency) at the 63 mg oral daily dosing (combined phase Ib/II data) were predominantly grade 1–2 events. Grade ≥3 events included diarrhea (7.4%), fatigue (5.6%), and alanine aminotransferase/aspartate aminotransferase elevations (5.6% and 3.7%, respectively). Neurotoxicity and neutropenia were not observed. Preliminary efficacy data in patients treated with ≥1 continuous cycle of 63 mg or higher included objective response rate in 6 of 29 (20.7%) patients with measurable disease (1 complete, 5 partial) and 14 of 48 (29.2%) patients had PSA declines. The Kaplan–Meier median radiographic progression-free survival was estimated to be 11.4 months (n = 55). Durable responses lasting >2.75 years were observed.Conclusions:This clinical trial demonstrated that chronic oral daily dosing of sabizabulin has a favorable safety profile with preliminary antitumor activity. These data support the ongoing phase III VERACITY trial of sabizabulin in men with mCRPC.

Supplementary Figures S1-S2 from Evaluation of Colon Cancer–Specific Antigen 2 as a Potential Serum Marker for Colorectal Cancer

Supplementary Data from A Phase Ib/II Study of Sabizabulin, a Novel Oral Cytoskeleton Disruptor, in Men with Metastatic Castration-resistant Prostate Cancer with Progression on an Androgen Receptor–targeting Agent

Supplementary Figures and Tables

Supplementary Figure from A Phase Ib/II Study of Sabizabulin, a Novel Oral Cytoskeleton Disruptor, in Men with Metastatic Castration-resistant Prostate Cancer with Progression on an Androgen Receptor–targeting Agent

Purpose:Androgen receptor (AR)-targeting prostate cancer drugs, which are predominantly competitive ligand-binding domain (LBD)-binding antagonists, are inactivated by common resistance mechanisms. It is important to develop next-generation mechanistically distinct drugs to treat castration- and drug-resistant prostate cancers.Experimental Design:Second-generation AR pan antagonist UT-34 was selected from a library of compounds and tested in competitive AR binding and transactivation assays. UT-34 was tested using biophysical methods for binding to the AR activation function-1 (AF-1) domain. Western blot, gene expression, and proliferation assays were performed in various AR-positive enzalutamide-sensitive and -resistant prostate cancer cell lines. Pharmacokinetic and xenograft studies were performed in immunocompromised rats and mice.Results:UT-34 inhibits the wild-type and LBD-mutant ARs comparably and inhibits the in vitro proliferation and in vivo growth of enzalutamide-sensitive and -resistant prostate cancer xenografts. In preclinical models, UT-34 induced the regression of enzalutamide-resistant tumors at doses when the AR is degraded; but, at lower doses, when the AR is just antagonized, it inhibits, without shrinking, the tumors. This indicates that degradation might be a prerequisite for tumor regression. Mechanistically, UT-34 promotes a conformation that is distinct from the LBD-binding competitive antagonist enzalutamide and degrades the AR through the ubiquitin proteasome mechanism. UT-34 has a broad safety margin and exhibits no cross-reactivity with G-protein–coupled receptor kinase and nuclear receptor family members.Conclusions:Collectively, UT-34 exhibits the properties necessary for a next-generation prostate cancer drug.

Colon cancer–specific antigen (CCSA)-3 and CCSA-4 are novel colon cancer markers identified by focused proteomic analysis of nuclear structural proteins. The goal of these studies was to evaluate serum-based CCSA-3 and CCSA-4 in the detection of individuals with preneoplastic and neoplastic lesions using ELISAs. Serum samples from 107 subjects undergoing colonoscopy, 28 subjects with colorectal cancer, and 125 subjects with benign disease or other types of cancer were evaluated. Individuals who underwent colonoscopy were classified into mutually exclusive categories, including normal colon, hyperplastic polyp, nonadvanced adenoma, and advanced adenoma. Sensitivity and specificity for both CCSA-3 and CCSA-4 were evaluated using receiver operating characteristic (ROC) curves. At a cutoff of 2 μg/mL for CCSA-3 and 0.3 μg/mL for CCSA-4, each marker detected all 28 colorectal cancers, for a sensitivity of 100% (lower 95% confidence bound, 89.8%). The sensitivity for detection of the combined end point of colorectal cancer and advanced adenoma for CCSA-3 was 89.1% [95% confidence interval (95% CI), 76.4–96.4%] and for CCSA-4 was 84.8% (95% CI, 71.1–93.7%) and 91.3% (95% CI, 79.2–97.6%) for either marker positive. The specificity in individuals with normal, hyperplastic polyps, or nonadvanced adenomas was 82.0% (95% CI, 72.4–89.4%) and 91.0% (95% CI, 83.0–96.0%) for CCSA-3 and CCSA-4, respectively. ROC curves for CCSA-3 and CCSA-4 reveal an area under the curve of 0.94 (95% CI, 0.90–0.98%). In these initial analyses, CCSA-3 and CCSA-4 show promise as potential serum markers for detection of colorectal cancer and advanced adenomas. [Cancer Res 2007;67(12):5600–5]

Supplementary Figure 1 - PDF file 202K, (A), expression of RBM3 in different human tissues. Data are mean � s.d. (n = 3). (B), expression of CIRBP in CD133+ and CD133- PrEC cells. mRNA levels of RBM3 and CIRBP was determined by RT-PCR. Data are mean � s.d. (n = 4). (C), mRNA levels of RBM3 were detected in the PC3-GFP and PC3-RBM3 clones by RT-PCR. Data are mean � s.d. (n = 3), *P < 0.05. (D), RBM3 protein was detected in both cytoplasmic (Cyto) and nuclear (Nu) components of PC3-GFP and PC3-RBM3 clones. Tubulin and Lammn A/C were used as loading controls for cytoplasmic and nuclear fractions, respectively. In all panels: G#1, PC3-GFP-clone #1; G#2, PC3-GFP-clone #2; R#1, PC3-RBM3-clone #1; R#6, PC3-RBM3-clone #6

Supplementary Figure 2 - PDF file 68K, (A), expression of cancer-related miRNAs was detected in the PC3-RBM3 and PC3-GFP clones using a cancer-specific miRNA PCR array. Left panel, selected miRNAs whose expression levels differed more than 1.5 fold in the clone R#1 compared to G#1. Red bars, differentiation-related miRNAs; black bars, other cancer-related miRNAs. Right panel, the up-regulation of miR-9 in PC3-RBM3 clones was validated by RT-PCR. Values are mean � s.d. (n = 3), *P < 0.05. (B), left panel, β3-tubulin expression was detected by Western blot in PC3-GFP and PC3-RBM3 clones. Right panel, quantitative evaluation of protein levels of β3-tubulin. Values are mean � s.d. (n = 3), *P < 0.05. (C), the immunohistochemical staining of RBM3 and β3-tubulin in the nerve fibers observed in human prostate tissue. Upper panels, low magnification; lower panels, high magnification. Scale bars, 100 �m. In all panels: G#1, PC3-GFP-clone #1; G#2, PC3-GFP-clone #2; R#1, PC3-RBM3-clone #1; R#6, PC3-RBM3-clone #6.expression of CDH2 in PC3-GFP and PC3-RBM3 clones

Supplementary Table 2 - PDF file 33K, Calculated size of PCR products for CD44 splicing variants

Supplementary Figure 5 - PDF file 104K, (A), mRNA levels of CD44v8-v10 (CD44v) were determined in human normal and prostate cancer tissues by RT-PCR. Normal, normal prostate tissue (n = 19); OC-PCa, organ-confined prostate cancer (n = 79); Met-PCa, metastatic prostate cancer (n = 23). (B), mRNA levels of CD44v were compared between patients with recurrent PCa (Rec, n = 44) and those without recurrent disease (Non-rec, n = 30). (C) and (D), mRNA levels of standard CD44 (CD44s) (C) or CD44v (D) were compared between patients with low grade PCa (Gleason score � 6, n = 21) and those with high grade disease (Gleason score > 6, n = 53). All experiments were repeated three times. Bars indicate median values

Supplementary Figures 1-2 from Initial Analyses of Colon Cancer–Specific Antigen (CCSA)-3 and CCSA-4 as Colorectal Cancer–Associated Serum Markers

Supplementary Figure 4 - PDF file 146K, mRNA expression of Cyclin D1 was evaluated in PC3 cells (A) and DU145 cells (B) that formed colonies in soft agar or those grew in the regular 2D culture condition by qRT-PCR. Values are mean � s.d. (n = 4). (C), PC3 cells were cultured under 32˚C for 0 hr to 144 hr, and mRNA level of cyclin D1 was detected by qRT-PCR. Values are mean � s.d. (n = 4). (D) Over-expression of CD44 variant and standard construct. LNCaP cells were transfected with pLenti-III-CD44s (CD44s), pLenti-III-CD44v8-v10 (CD44v8-10) or empty vector. After 48 hr of transfection, cells were collected and the expression of mRNA and protein of CD44 were detected by RT-PCR and Western blot, respectively. Data are mean � s.d. (n = 3), *P < 0.05

Supplementary Figure 3 - PDF file 244K, (A), CD44 variant mRNAs were amplified by PCR using the general primers c13 and hs3'. The PCR products at size of 650 bp and 250 bp were cut and subjected to direct DNA sequencing. The numbers in the block are exons number of CD44. N, negative control; G#1, PC3-GFP-clone #1. (B), schematic diagram of designing siRNAs specific to CD 44 variant exons v8-v10 (siC1, siC2) and primers specific to CD44v8-v10 (CD44v) or standard CD44 (CD44s). Primers c13 and hs3' can amplify both CD44s and CD44v. Primers p1 and p2 can only amplify CD44v8-v10, while primers p3 and p4 are specific to standard CD44s. Primer hs5' is the outside primer of the nest PCR. (C), the specificity of siRNAs targeting for CD44v8-v10. Variant exon-specific PCR was performed using primer p1 and p2. CD44s was amplified using CD44 standard-specific primer p3 and p4. siN, non-target siRNA. Data are mean � s.d. (n = 3), *P < 0.05. (D), the efficiency of siRNA pool targeting RBM3. Cells were treated with siRBM3 or non-targeting siRNA (siN) for 48 hr. The expression of mRNA and protein of CD44 were detected by RT-PCR and Western blot, respectively. R#1, PC3-RBM3-clone #1; R#6, PC3-RBM3-clone #6. Data are mean � s.d. (n = 3), *P < 0.05

Supplementary Table 1 - PDF file 43K, mRNA expression of stem cell-related gene using a Stem Cell PCR array

Supplementary documents - PDF file 122K, Supplementary methods and supplementary figures legends

Targeting the androgen receptor (AR) may be the next important endocrine therapy for women with advanced breast cancer. AR is the most abundantly expressed steroid receptor in breast cancer and has been demonstrated to be a tumor suppressor when activated. Enobosarm is an oral selective nonsteroidal agonist that activates the AR in breast cancer. Enobosarm has an extensive clinical experience in 25 clinical trials and 1,450 dosed subjects including in breast cancer where three Phase 2 studies have been conducted two of which were in women (158 subjects) who had AR+/ER+/HER2- metastatic breast cancer (MBC).The larger Phase 2 clinical trial (G200802) evaluated 9mg and 18mg enobosarm daily oral dosing in 136 women with ER+/HER2- MBC who previously responded to endocrine treatment. Patients were heavily pretreated having progressed on an average of 3 endocrine treatments and 90% had prior chemotherapy. Enobosarm showed efficacy activity in the overall study with a clinical benefit rate at 6 months of 32% (95% CI: 19.5%,46.7%) for the 9 mg and 29% (95% CI: 17.1%,43.1%) for the 18 mg evaluable cohorts. Quality of life assessments showed significant improvement from baseline for both enobosarm cohorts (p=0.002). Enobosarm was well tolerated at both doses. In a post-hoc analysis in all patients (9mg and 18mg) with known AR status and measurable disease (n=84), AR expression in breast. cancer tissue (%AR nuclei staining) correlated with efficacy outcomes. When comparing AR nuclei staining ≥40% (n=47) compared to patients with an AR nuclei staining Citation Format: Adam Brufsky, Hannah Linden, Hope Rugo, Charles Vogel, Joyce A O'Shaughnessy, Robert H Getzenberg, K. Gary Barnette, Domingo Rodriguez, Mitchell S Steiner, Erica Mayer. Randomized, multicenter, international phase 3 ARTEST study to evaluate the efficacy and safety of enobosarm versus active control for the treatment of AR+ ER+ HER2- metastatic breast cancer in patients who progressed on a nonsteroidal aromatase inhibitor, fulvestrant and CDK 4/6 inhibitor [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr OT2-17-01.

Introduction: Hormonal agents remain the most effective therapies for estrogen receptor positive (ER+) HER2- breast cancer. The androgen receptor (AR) is the most highly expressed steroid receptor found in up to 95% of ER+ breast cancer patients. Androgen agonists have antiproliferative activity in ER+ breast cancer and have been used in treatment, however their lack of availability and virilizing side effects have limited their use. Enobosarm is a non-steroidal tissue-selective AR modulator that that is being developed for AR targeted treatment of ER+/AR+ breast cancer. Methods: An international, Phase 2, open label, parallel design, randomized study was conducted in 136 patients (pts) to investigate the efficacy and safety of enobosarm in postmenopausal women with metastatic ER+/AR+ breast cancer that progressed on previous endocrine therapy. Pts were randomized to receive 9 mg (n=72) or 18 mg (n=64) of oral daily enobosarm. The primary endpoint was clinical benefit rate (CBR) at 24 weeks (defined as CR, PR or SD) by RECIST 1.1. Secondary endpoints included objective response rate, best overall response rate (BOR), progression free survival (PFS), duration of clinical benefit. Results: The study population consisted of heavily pre-treated pts with a mean of 4 (range 1-6) prior hormone therapies and >90% receiving one prior course of chemotherapy. Median age was 60.8 years (35-83) for 9 mg and 62.1 (42-81) for the 18 mg cohort. AR positivity was centrally confirmed in 73.6% and 81.2% in the 9 and 18 mg cohorts, respectively. Efficacy: In the evaluable pts, 50 in the 9 mg arm and 52 in the 18 mg arm (AR confirmed), 32% of the 9mg cohort met the primary endpoint of CBR at 24 weeks (95% CI, 19.5%; 46.7%) and 29% (95% CI, 17.1%; 43.1%) in the 18 mg cohort. The BOR was 2 CRs, 10 PRs in the 9 mg and 3 CRs,7 PRs in the 18 mg group by central review. Median PFS was 5.6 (2.9 to 27.5) and 4.2 (2.8 to 11) months (mo) in the 9 mg and 18 mg groups. The median duration of treatment was 4.0 months (0.23-30.3 months) in the 9 mg group and 3.8 months (0.5-16.7 months) in the 18 mg group. At the time the study was terminated, the median duration of clinical benefit was not reached (NR) in the 9 mg group (range 8.2 mo to NR) and 14.1 mo (range 11.0 to 16.5) in the 18 mg group. QOL: Using a standardized instrument of generic health status (EQ-5D), a significant percentage of pts reported improvement in measurements including mobility (40%, 50%), anxiety/depression (50%, 29%) and pain discomfort (50%, 31%) for the 9 and 18 mg groups, respectively. Drug related severe adverse events (SAEs) (Grades 3-4) were observed in 6 (8.0%) at the 9 mg and 10 (16.4%) at the 18 mg dose. The SAEs (Grade 3-4) attributed to the study drug by the site investigator were for the 9 mg group: fatigue (1), elevated transaminases (2), headache (1), hypercalcemia (2) and anemia (1). For the 18 mg group the drug attributable SAEs (Grade 3-4) were: dry mouth (1), increased aminotransferase (2), decreased white blood cell count (1), fatigue (2), hypercalcemia (1), decreased appetite (1), headache (1), tumor flare (2), agitation (1), lymphadenopathy (1) and acute kidney injury (1). Conclusions: In this Phase 2 parallel design study, enobosarm (9 mg and 18 mg) has significant clinical activity and was well tolerated in heavily pretreated patients with ER+/AR+ metastatic breast cancer. Given the limited options of hormonal therapy for metastatic ER+ breast cancer, enobosarm merits further clinical development in a Phase 3 clinical program as an AR targeted treatment for metastatic ER+AR+ breast cancer. Citation Format: Carlo Palmieri, Hannah Linden, Stephen Birrell, Elgene Lim, Lee S Schwartzberg, Hope S Rugo, Patrick Cobb, Kirti Jain, Charles Vogel, Joyce A O’Shaughnessy, Robert H Getzenberg, Mitchell S Steiner, Adam Brufsky, Beth Overmoyer. Efficacy and safety of enobosarm, a selective androgen receptor modulator, to target AR in women with advanced ER+/AR+ breast cancer - final results from an international Phase 2 randomized study [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PD8-10.

Current clinical tests for prostate cancer (PCa), such as the PSA test, are not fully capable of discerning patients that are highly likely to develop metastatic prostate cancer (MPCa). Hence, more accurate prediction tools are needed to provide treatment strategies that are focused on the different risk groups. Cancer/testis antigens (CTAs) are expressed during embryonic development and present aberrant expression in cancer making them ideal tumor specific biomarkers. Here, the potential use of a panel of CTAs as a biomarker for PCa detection as well as metastasis prediction is explored. We initially identified eight CTAs (CEP55, NUF2, PAGE4, PBK, RQCD1, SPAG4, SSX2andTTK) that are differentially expressed in MPCa when compared to local disease and used this panel to compare the gene and protein expression profiles in paired PCa and normal adjacent prostate tissue. We identified differential expression of all eight CTAs at the protein level when comparing 80 paired samples of PCa and the adjacent non-cancer tissue. Using multiple logistic regression we also show that a panel of these CTAs present high accuracy to discriminate normal from tumor samples. In summary, this study provides evidence that a panel of CTAs, differentially expressed in aggressive PCa, is a potential biomarker for diagnosis and prognosis to be used in combination with the current clinically available tools and is also a potential target for immunotherapy development.

Purpose: Androgen receptor (AR)-targeting prostate cancer drugs, which are predominantly competitive ligand-binding domain (LBD)-binding antagonists, are inactivated by common resistance mechanisms. It is important to develop next-generation mechanistically distinct drugs to treat castration- and drug-resistant prostate cancers. Experimental Design: Second-generation AR pan antagonist UT-34 was selected from a library of compounds and tested in competitive AR binding and transactivation assays. UT-34 was tested using biophysical methods for binding to the AR activation function-1 (AF-1) domain. Western blot, gene expression, and proliferation assays were performed in various AR-positive enzalutamide-sensitive and -resistant prostate cancer cell lines. Pharmacokinetic and xenograft studies were performed in immunocompromised rats and mice. Results: UT-34 inhibits the wild-type and LBD-mutant ARs comparably and inhibits the in vitro proliferation and in vivo growth of enzalutamide-sensitive and -resistant prostate cancer xenografts. In preclinical models, UT-34 induced the regression of enzalutamide-resistant tumors at doses when the AR is degraded; but, at lower doses, when the AR is just antagonized, it inhibits, without shrinking, the tumors. This indicates that degradation might be a prerequisite for tumor regression. Mechanistically, UT-34 promotes a conformation that is distinct from the LBD-binding competitive antagonist enzalutamide and degrades the AR through the ubiquitin proteasome mechanism. UT-34 has a broad safety margin and exhibits no cross-reactivity with G-protein–coupled receptor kinase and nuclear receptor family members. Conclusions: Collectively, UT-34 exhibits the properties necessary for a next-generation prostate cancer drug.

INTRODUCTION AND OBJECTIVES:VERU-111 is a novel, oral α and β tubulin inhibitor that blocks tubulin polymerization and is not a substrate for multi-drug resistance. In xenograft mouse models of tax...

Stress urinary incontinence (SUI), a prevalent condition, is represented by an involuntary leakage of urine that results, at least in part, from weakened or damaged pelvic floor muscles and is triggered by physical stress. Current treatment options are limited with no oral therapies available. The pelvic floor is rich in androgen receptor and molecules with anabolic activity including selective androgen receptor modulators (SARMs) may serve as therapeutic options for individuals with SUI. In this study, two SARMs (GTx-024 and GTx-027) were evaluated in a post-menopausal animal model in order to determine their effect on pelvic floor muscles. Female C57BL/6 mice were ovariectomized and their pelvic muscles allowed to regress. The animals were then treated with vehicle or doses of GTx-024 or GTx-027. Animal total body weight, lean body mass, and pelvic floor muscle weights were measured along with the expression of genes associated with muscle catabolism. Treatment with the SARMs resulted in a restoration of the pelvic muscles to the sham-operated weight. Coordinately, the induction of genes associated with muscle catabolism was inhibited. Although a trend was observed towards an increase in total lean body mass in the SARM-treated groups, no significant differences were detected. Treatment of an ovariectomized mouse model with SARMs resulted in an increase in pelvic floor muscles, which may translate to an improvement of symptoms associated with SUI and serves as the basis for evaluating their clinical use. J. Cell. Biochem. 118: 640-646, 2017. © 2016 Wiley Periodicals, Inc.

Aim: To develop and apply a heat-responsive and secreted reporter assay for comparing cellular response to nanoparticle (NP)- and macroscopic-mediated sublethal hyperthermia. Materials & methods: Reporter cells were heated by water bath (macroscopic heating) or iron oxide NPs activated by alternating magnetic fields (nanoscopic heating). Cellular responses to these thermal stresses were measured in the conditioned media by secreted luciferase assay. Results & conclusion: Reporter activity was responsive to macroscopic and nanoparticle heating and activity correlated with measured macroscopic thermal dose. Significant cellular responses were observed with NP heating under doses that were insufficient to measurably change the temperature of the system. Under these conditions, the reporter response correlated with proximity to cells loaded with heated nanoparticles. These results suggest that NP and macroscopic hyperthermia may be distinctive under conditions of mild hyperthermia. Original submitted 10 May 2013; Revised submitted 31 October 2013

Prostate cancer is a heterogeneous disease and thus, it is important to understand whether among the heterogeneous collection of cell types, androgen-deprivation insensitive cells exist prior to hormonal manipulation. We established several LNCaP subclones with distinct insensitivities to androgen deprivation from a parental LNCaP cell line. In the resulting clones, the sensitivity to androgen-deprivation negatively correlated with their PSA expression levels. In two of these clones, an androgen insensitive clone, LNCaP-cl1, and an androgen sensitive clone, LNCaP-cl5, the DNA copy number differed significantly, indicating that these clones contain genetically distinct cells. LNCaP-cl1 had higher PSA expression but lower invasiveness and tumor growth potential than LNCaP-cl5. The expression levels of two genes that are known to be regulated by miR-21, an androgen-regulated microRNA, Sprouty1 (SPRY1) and Jagged1 (JAG1) were significantly lower in LNCaP-cl1 than in LNCaP-cl5. Knocking down SPRY1 in LNCaP cells enhanced PSA expression and cell proliferation. JAG1 administration in LNCaP cells enhanced cell invasion and JAG1 knockdown in PC3 cells suppressed cell invasion and tumor formation. These results indicated that the expression differences in SPRY1 and JAG1 may contribute to the phenotypic differences between the LNCaP-cl1 and LNCaP-cl5 clones. In tissue samples, SPRY1 expression levels were significantly lower in prostate cancer patients with PSA recurrence after surgical treatment (P = 0.0076) and JAG1 expression levels were significantly higher in Gleason sum (GS) 8–9 disease than in GS 5–6 (P = 0.0121). In summary a random population of LNCaP cells comprises a heterogeneous group of cells with different androgen-deprivation sensitivities and potential for invasiveness.

Cancer cells typically demonstrate altered morphology during the various stages of disease progression as well as metastasis. While much is known about how altered cell morphology in cancer is a result of genetic regulation, less is known about how changes in cell morphology affect cell function by influencing gene expression. In this study, we altered cell morphology in different types of cancer cells by disrupting the actin cytoskeleton or by modulating attachment and observed a rapid up-regulation of growth differentiation factor 15 (GDF15), a member of the transforming growth factor-beta (TGF-β) super-family. Strikingly, this up-regulation was sustained as long as the cell morphology remained altered but was reversed upon allowing cell morphology to return to its typical configuration. The potential significance of these findings was examined in vivo using a mouse model: a small number of cancer cells grown in diffusion chambers that altered morphology increased mouse serum GDF15. Taken together, we propose that during the process of metastasis, cancer cells experience changes in cell morphology, resulting in the increased production and secretion of GDF15 into the surrounding environment. This indicates a possible relationship between serum GDF15 levels and circulating tumor cells may exist. Further investigation into the exact nature of this relationship is warranted.

Cancer/testis antigens (CTAs) are a group of tumour-associated antigens (TAAs) that display normal expression in the adult testis--an immune-privileged organ--but aberrant expression in several types of cancers, particularly in advanced cancers with stem cell-like characteristics. There has been an explosion in CTA-based research since CTAs were first identified in 1991 and MAGE-1 was shown to elicit an autologous cytotoxic T-lymphocyte (CTL) response in a patient with melanoma. The resulting data have not only highlighted a role for CTAs in tumorigenesis, but have also underscored the translational potential of these antigens for detecting and treating many types of cancers. Studies that have investigated the use of CTAs for the clinical management of urological malignancies indicate that these TAAs have potential roles as novel biomarkers, with increased specificity and sensitivity compared to those currently used in the clinic, and therapeutic targets for cancer immunotherapy. Increasing evidence supports the utilization of these promising tools for urological indications.

Cysteine-rich angiogenic inducer 61 (Cyr61) is an extracellular matrix protein involved in the transduction of growth factor and hormone signaling that is frequently altered in expression in several types of cancers. In prostate cancer (PCa), Cyr61 is highly expressed in organ-confined disease. Further, Cyr61 expression levels are associated with a lower risk of disease recurrence, and can be quantitatively measured in the serum. Considered together, these results indicate that Cyr61 is a potential and clinically useful tissue, as well as serum-based biomarker for differentiating lethal and non-lethal PCa.

Prostate fibroblasts promote prostate cancer progression by secreting factors that enhance tumour growth and induce the migration and invasion of prostate cancer cells. Considering the role of fibroblasts in cancer progression, we hypothesized that prostate cancer cells recruit these cells to their vicinity, where they are most directly available to influence cancer cell behaviour. To test this hypothesis, we performed modified Boyden chamber assays assessing the migration and collagen I invasion of normal primary prostate fibroblasts (PrSCs) and prostate cancer-associated fibroblasts (PCAFs) in response to media conditioned by the metastatic prostate cancer cell lines PC-3, LNCaP and DU145. During 4-hr incubations, PrSCs and PCAFs migrated and invaded in response to the conditioned media. To identify candidate proteins in the conditioned media that produced these effects, we performed cytokine antibody arrays and detected angiogenin in all three media. Angiogenin-blocked PC-3-conditioned medium, obtained using an anti-angiogenin polyclonal antibody or angiogenin siRNA, significantly reduced PC-3-induced PrSC and PCAF collagen I invasion. Furthermore, angiogenin alone at 1, 2 and 5 ng/ml significantly stimulated PCAF collagen I invasion. These results suggest that PC-3-derived angiogenin stimulates the invasion of normal prostate fibroblasts and PCAFs and is sufficient for invasion of the latter. Because prostate fibroblasts play key roles in prostate cancer progression, targeting their invasion using an anti-angiogenin-based therapy may be a strategy for preventing or treating advanced prostate cancer.

Cysteine-rich angiogenic inducer 61 (Cyr61) is an extracellular matrix protein involved in the transduction of growth factor and hormone signaling. Previously, we demonstrated that Cyr61 was highly expressed in prostate cancer (PCa) but that the expression levels were associated with a lower risk of PCa recurrence. In the present study, we demonstrate that serum Cyr61 is a potential biomarker that correlates with PCa aggressiveness. Furthermore, we also explore the potential mechanism underlying the changes in Cyr61 expression during PCa progression.Cyr61 concentrations in the medium from PCa cell lines and in serum samples obtained from PCa patients were measured by sandwich ELISA. Serum Cyr61 levels were correlated with disease characteristics and the association between Cyr61 expression changes by several types of stimulation or stress and cAMP/cAMP-dependent protein kinase (PKA) pathway were examined.There was a positive correlation between Cyr61 levels in cell supernatants and mRNA expression in these cell lines. Serum Cyr61 levels were significantly higher in non-organ-confined PCa patients (116.3 ± 140.2 ng/ml) than in organ-confined PCa patients (79.7 ± 56.1 ng/ml) (P = 0.031). Cyr61 expression was up-regulated in response to both lysophosphatidic acid and androgen treatments which promoted PCa cell invasion. Serum starvation and phosphoinositide-3-kinase inhibition also resulted in Cyr61 up-regulation; however, they suppressed cell proliferation. Cyr61 up-regulation was correlated with an increase in cAMP and suppressed by PKA inhibition.These findings suggest that Cyr61 expression in PCa is regulated by the cAMP/PKA pathway and that circulating Cyr61 levels are a potential serum-based biomarker for characterizing PCa.

The cancer/testis antigens (CTAs) are a group of heterogeneous proteins that are typically expressed in the testis but aberrantly expressed in several types of cancer. Although overexpression of CTAs is frequently associated with advanced disease and poorer prognosis, the significance of this correlation is unclear since the functions of the CTAs in the disease process remain poorly understood. Here, employing a bioinformatics approach, we show that a majority of CTAs are intrinsically disordered proteins (IDPs). IDPs are proteins that, under physiological conditions in vitro, lack rigid 3D structures either along their entire length or in localized regions. Despite the lack of structure, most IDPs can transition from disorder to order upon binding to biological targets and often promote highly promiscuous interactions. IDPs play important roles in transcriptional regulation and signaling via regulatory protein networks and are often associated with dosage sensitivity. Consistent with these observations, we find that several CTAs can bind DNA, and their forced expression appears to increase cell growth implying a potential dosage-sensitive function. Furthermore, the CTAs appear to occupy "hub" positions in protein regulatory networks that typically adopt a "scale-free" power law distribution. Taken together, our data provide a novel perspective on the CTAs implicating them in processing and transducing information in altered physiological states in a dosage-sensitive manner. Identifying the CTAs that occupy hub positions in protein regulatory networks would allow a better understanding of their functions as well as the development of novel therapeutics to treat cancer.

Somatic cellular evolution is becoming a popular biological explanation for the common rapid development of resistance to almost every form of cancer therapy and against almost every form of advanced human solid tumors. As a result of the historical power of evolution within nature, this common biological interpretation of the failure to cancer therapy, is leading to a growing despair for many investigators and a stronger turn towards prevention through lifestyle changes. The absolute explosion of molecular scientific discoveries since 1983, in the reductionist identification of specific cancer therapeutic targets, has failed to deliver the impact in the clinic that many of us would have hoped would have result by this time. Personalized molecular medicine may help us reclassify appropriate therapeutic subgroups, but will it significantly impact on the overall specific survival times for all of the cancers combined within the organ type for the entire population? How might we approach this therapeutic dilemma by utilizing new therapeutics insights designed on proven principles of evolution? In other words, can we fight the development of therapeutic resistance in cancer cells by turning established aspects of evolution against the survival of cancer cells within the individual patient. Here we review the concepts of changing the heat habitat and microenvironment of the cancer cell to alter the higher order organization and function of DNA. We have proposed that heat may be a major factor in determining the lasting therapeutic effect on many types of far advanced metastatic tumors.

The microenvironment is central to many aspects of cancer pathobiology and has been proposed to play a role in the development of cancer cell resistant to therapy. To examine the response to microenvironmental conditions, two paclitaxel resistant prostate cancer cell lines (stable and reversible) and one reversible heat resistant cell line were studied. In comparison to their parental cell lines, both paclitaxel resistant cell lines (stable and reversible) were more sensitive to microenvironmental heat, potentially yielding a synergistic therapeutic opportunity. In the two phenotypic cells repopulated after acute heat or paclitaxel treatments, there was an inverse correlation between paclitaxel and heat resistance: resistance to paclitaxel imparted sensitivity to heat; resistance to heat imparted sensitivity to paclitaxel. These studies indicate that as cancer cells evolve resistance to single microenvironmental stress they may be more sensitive to others, perhaps allowing us to design new approaches for prostate cancer therapy.

Most proteins encoded by the nuclear genome are synthesized in the cytoplasm and fold into precise 3D structures. During synthesis, the nascent polypeptide begins to fold as it traverses the large subunit of the ribosome and is assisted by molecular chaperones in attaining its precise folded/highly ordered state efficiently and in a biologically relevant timescale. Proteins that are misfolded are culled, re-routed, and marked by mechanisms such as ubiquitinylation for degradation ensuring strict quality control (QC). In addition to the highly ordered “globular” proteins, emerging evidence indicates that a large fraction of the proteome also comprises the so-called “Intrinsically Disordered Proteins” (IDPs). IDPs are proteins that lack rigid 3D structures and instead, exist as dynamic ensembles. The dynamic structures in the IDPs have many similarities with “normal” globular proteins such as the native (ordered), and non-native (molten globule, pre-molten globule, and coil-like) states seen during folding of “normal” globular proteins. However, unlike the case of the nascent globular proteins, IDPs evade being detected as “misfolded” and degraded by the cell’s QC system. We refer to this paradox as the order/disorder paradox and postulate that the IDPs capitalize on their intrinsic promiscuity and ability to undergo disorder-to-order transitions upon binding to biological targets (coupled folding and binding) to escape the cell’s surveillance machinery. Understanding the mechanism by which the IDPs evade the quality check has wide implications from protein folding to disease biology since the aggregation of misfolded proteins underlies several debilitating illnesses such as many neurodegenerative diseases and cancer.

The metastatic invasion of cancer cells from primary tumors to distant ecological niches, rather than the primary tumors, is the cause of much cancer mortality [Zhang QB, et al. (2010) Int J Cancer 126:2534–2541; Chambers AF, Goss PE (2008) Breast Cancer Res 10:114]. Metastasis is a three-dimensional invasion process where cells spread from their site of origin and colonize distant microenvironmental niches. It is critical to be able to assess quantitatively the metastatic potential of cancer cells [Harma V, et al. (2010) PLoS ONE 5:e10431]. We have constructed a microfabricated chip with a three-dimensional topology consisting of lowlands and isolated square highlands (Tepuis), which stand hundreds of microns above the lowlands, in order to assess cancer cell metastatic potential as they invade the highlands. As a test case, the invasive ascents of the Tepui by highly metastatic PC-3 and noninvasive LNCaP prostate cancer cells were used. The vertical ascent by prostate cancer cells from the lowlands to the tops of the Tepui was imaged using confocal microscopy and used as a measure of the relative invasiveness. The less-metastatic cells (LNCaP) never populated all available tops, leaving about 15% of them unoccupied, whereas the more metastatic PC-3 cells occupied all available Tepuis. We argue that this distinct difference in invasiveness is due to contact inhibition.

Background The cancer/testis antigens (CTAs) are a unique group of proteins normally expressed in germ cells but aberrantly expressed in several types of cancers including prostate cancer (PCa). However, their role in PCa has not been fully explored.

BACKGROUND Chronic inflammation is commonly observed in benign prostate hyperplasia (BPH), and prostate tissue often contains increased inflammatory infiltrates, including T cells and macrophages. Cytokines are not only key mediators of inflammation but may also play important roles in the initiation and progression of BPH.