Search

Supplementary Figure S12 - PDF file 118K, Prosaposin mimetic peptide DWLPK upregulates Tsp-1 in tumor-recruited Gr1 cells in the lung

Supplementary methods - PDF file 98K, Supplementary methods

Purpose: Prostate cancer is the third leading cause of cancer death in the United States, following lung and colorectal cancer. We previously identified WDR19 as a prostate-specific, androgen-regulated gene. Here, we evaluate its utility as a prostate cancer tissue marker for diagnosis and prognostic evaluation.Experimental Design: Real-time quantitative PCR was done on a panel of prostate tissue isolated by laser capture microdissection. After generating antibodies against WDR19, tissue microarrays (TMA) were employed to compare WDR19 expression between normal, benign prostatic hyperplasia, and prostate cancer tissue.Results: Using microarrays and real-time quantitative PCR, we showed that WDR19 mRNA expression was increased in cancer. We further showed that WDR19 protein is localized to cytoplasmic subcellular granules and is expressed exclusively in prostate epithelia. Large-scale immunohistochemical staining using TMAs reveals a significant percentage of increase in intensely staining tissue cores in cancer tissue when compared with normal or benign prostatic hyperplastic tissue. Based on the analysis of a separate TMA for which clinical follow-up information was available, low-intensity WDR19 staining was significantly associated with decreased time to biochemical failure (P = 0.006) and with decreased time to locoregional recurrence (P = 0.050).Conclusions: WDR19 should be added to the list of prostate cancer tissue markers. The continued expansion of a multiple-marker panel will conceivably increase the sensitivity and specificity of prostate cancer diagnosis and prognosis.

Supplementary Table S1 from WDR19 Expression is Increased in Prostate Cancer Compared with Normal Cells, but Low-Intensity Expression in Cancers is Associated with Shorter Time to Biochemical Failures and Local Recurrence

The prognostic importance of transcription factors promoting epithelial–mesenchymal transition (EMT) and angiogenesis has not been well explored in prostate cancer patients with long follow-up, nor the interplay between these factors. The objective of this study was to assess the individual protein expression and co-expression of Twist, Slug (Snai2), Snail (Snai1), and hypoxia-inducible factor-1 alpha (Hif-1α) in prostate cancer in relation to EMT, angiogenesis, hypoxia, tumour features, disease recurrence, and patient survival. Immunohistochemical staining was performed on tissue microarray sections from 338 radical prostatectomies with long follow-up. In addition, 41 cases of prostatic hyperplasia, 33 non-skeletal metastases, 13 skeletal metastases, and 33 castration-resistant prostate carcinomas were included. Our findings were validated in external gene expression data sets. Twist was overexpressed in primary prostate cancer and markedly reduced in distant metastases (p

Epithelial–mesenchymal transition (EMT) is important for tumour cell invasion and metastasis and is a feature of aggressive carcinomas. EMT is characterised by reduced E‐cadherin and increased N‐cadherin expression (EN‐switch), and increased expression of the EMT‐regulating transcription factor Forkhead box protein C2 (FOXC2) has been associated with progression and poor prognosis in various malignancies. FOXC2 was recently highlighted as a novel therapy target in prostate cancer, but survival data on FOXC2 are lacking. This study evaluates the expression of FOXC2, E‐cadherin and N‐cadherin in different prostatic tissues focusing on EMT, clinico‐pathological phenotype, recurrence and patient survival. Tissue microarray sections from 338 radical prostatectomies (1986–2007) with long and complete follow‐up, 33 castration resistant prostate cancers, 33 non‐skeletal metastases, 13 skeletal metastases and 41 prostatic hyperplasias were stained immunohistochemically for FOXC2, E‐cadherin and N‐cadherin. FOXC2 was strongly expressed in primary carcinomas, including castration resistant tumours and metastatic lesions as compared to benign prostatic hyperplasia. A hybrid epithelial–mesenchymal phenotype, with co‐expression of E‐cadherin and N‐cadherin, was found in the majority of skeletal metastases and in a substantial proportion of castration resistant tumours. In localised carcinomas, the EN‐switch was associated with adverse clinico‐pathological variables, such as extra‐prostatic extension, high pathological stage and lymph node infiltration. In univariate survival analyses of the clinically important, large subgroup of 199 patients with Gleason score 7, high FOXC2 expression and EN‐switching were significantly associated with shorter time to clinical recurrence, skeletal metastases and cancer specific death. In multivariate Cox' survival analysis, high FOXC2 and the EN‐switch, together with Gleason grade group (GG3 versus GG2), were independent predictors of time to these end‐points. High FOXC2 gene expression (mRNA) was also related to patient outcome, validating our immunohistochemical findings. FOXC2 and factors signifying EMT or its intermediate states may prove important as biomarkers for aggressive disease and are potential novel therapy targets in prostate cancer. publishedVersion

PURPOSE: To validate the MRI grading system proposed by Mehralivand et al in 2019 (the “extraprostatic extension [EPE] grade”) in an independent cohort and to compare the Mehralivand EPE grading system with EPE interpretation on the basis of a five-point Likert score (“EPE Likert”). MATERIALS AND METHODS: A total of 310 consecutive patients underwent multiparametric MRI according to a standardized institutional protocol before radical prostatectomy was performed by using the same 1.5-T MRI unit at a single institution between 2010 and 2012. Two radiologists blinded to clinical information assessed EPE according to standardized criteria. On the basis of the readings performed until 2017, the diagnostic performance of EPE Likert and Mehralivand EPE score were compared using receiver operating characteristics (ROC) and decision curve methodology against histologic EPE as standard of reference. Prediction of biochemical recurrence-free survival (BRFS) was assessed by Kaplan-Meier analysis and log rank test. RESULTS: Of the 310 patients, 80 patients (26%) had EPE, including 33 with radial distance 1.1 mm or greater. Interrater reliability was fair (weighted κ 0.47 and 0.45) for both EPE grade and EPE Likert. Sensitivity for identifying EPE using EPE grade versus EPE Likert was 0.83 versus 0.86 and 0.86 versus 0.91 for radiologist 1 and 2, respectively. Specificity was 0.48 versus 0.58 and 0.39 versus 0.70 (P < .05 for radiologist 2). There were no significant differences in the ROC area under the curve or on decision curve analysis. Both EPE grade and EPE Likert were significant predictors of BRFS. CONCLUSION: Mehralivand EPE grade and EPE Likert have equivalent diagnostic performance for predicting EPE and BRFS with a similar degree of observer dependence. © RSNA, 2020 Keywords: MR-Imaging, Neoplasms-Primary, Observer Performance, Outcomes Analysis, Prostate, Staging Supplemental material is available for this article. See also the commentary by Choyke in this issue.

Objective To evaluate the performance of real-time elastography (RTE) in an initial biopsy setting. Patients and Methods In the period from February 2011 to June 2012, 127 consecutive patients were included in the study. We used a Hitachi Preirus with Hi-RTE module, a prostate end-fire transrectal probe was used for RTE and for targeted biopsies, and a simultaneous biplane probe was used for the standard systematic biopsies. The peripheral zone of the prostate was divided into six regions, and each biopsy obtained was referred to a specific region. All patients were first examined with RTE and, if cancer was suspected, targeted biopsies were taken. A standard systematic 10-core biopsy was then taken in all patients. Results In all, 64 (50%) patients were diagnosed with prostate cancer in the initial biopsy setting. Three patients were diagnosed solely on RTE-targeted biopsies, 31 were found only in systematic biopsies, and 30 were correctly diagnosed with both methods. In the RTE-positive group there was a significantly higher frequency of positive cores, a lower prostate volume, a higher Gleason score, and a higher fraction of cancer tissue in each core. In a multiple regression model RTE was an independent marker for high-risk cancer. The sensitivity of 42% for all prostate cancers increased to 60% for high-grade prostate cancers. Similarly, the negative predictive value increased from 79% to 97%. An additional eight patients were diagnosed with prostate cancer during the study period. Conclusions A positive RTE is an independent marker for detection of high-risk prostate cancer, and a negative RTE argues against such. RTE with targeted biopsies cannot replace systematic biopsies, but provides valuable additional information about the tumours.

Metastatic tumors have been shown to establish permissive microenvironments for metastases via recruitment of bone marrow–derived cells. Here, we show that metastasis-incompetent tumors are also capable of generating such microenvironments. However, in these situations, the otherwise prometastatic Gr1+ myeloid cells create a metastasis-refractory microenvironment via the induction of thrombospondin-1 (Tsp-1) by tumor-secreted prosaposin. Bone marrow–specific genetic deletion of Tsp-1 abolished the inhibition of metastasis, which was restored by bone marrow transplant from Tsp-1+ donors. We also developed a 5-amino acid peptide from prosaposin as a pharmacologic inducer of Tsp-1 in Gr1+ bone marrow cells, which dramatically suppressed metastasis. These results provide mechanistic insights into why certain tumors are deficient in metastatic potential and implicate recruited Gr1+ myeloid cells as the main source of Tsp-1. The results underscore the plasticity of Gr1+ cells, which, depending on the context, promote or inhibit metastasis, and suggest that the peptide could be a potential therapeutic agent against metastatic cancer. Significance: The mechanisms of metastasis suppression are poorly understood. Here, we have identified a novel mechanism whereby metastasis-incompetent tumors generate metastasis-suppressive microenvironments in distant organs by inducing Tsp-1 expression in the bone marrow–derived Gr1+ myeloid cells. A 5-amino acid peptide with Tsp-1–inducing activity was identified as a therapeutic agent against metastatic cancer. Cancer Discov; 3(5); 578–89. ©2013 AACR. This article is highlighted in the In This Issue feature, p. 471

Purpose To evaluate clinico-pathological and molecular prognostic factors in a well-defined series of posterior uveal melanoma (UM) with focus on chromosomal aberrations and mutations in the GNAQ, GNA11 and BRCA1-associated protein 1 (BAP1) genes. Methods Formalin-fixed paraffin-embedded (FFPE) tissue samples were obtained from 50 consecutive eyes enucleated for UM between 1993 and 2005. The material was tested for loss of chromosome 3 and gain of chromosome 8q gene signatures by selective molecular gene markers using multiplex ligation-dependent probe amplification (MLPA), and for DNA mutations in the GNAQ, GNA11 and BAP1 genes. Results After a mean follow-up of 83 months (range, 8–205 months), 21 patients had died of metastatic UM and 16 patients of other causes. Tumour diameter, ciliary body involvement, mixed/epithelioid cell types, mitotic index, Ki-67 proliferation index, loss of chromosome 3 and gain of chromosome 8q showed statistically significant associations with metastatic disease. There were no significant differences in the prevalence of GNAQ and GNA11 mutations between patients with or without metastatic disease. Mutational analysis of the BAP1 gene was performed in 32 primary UM and in five UM liver metastases. Nine different BAP1 missense mutations were identified. BAP1 mutations were not more common in metastasizing than in nonmetastasizing UM. Conclusion The molecular gene markers showing loss of chromosome 3 and gain of 8q gene signatures were associated with an increased risk of metastatic disease. BRCA1-associated protein 1 (BAP1) gene mutation status had no prognostic significance. The frequency and spectrum of BAP1 mutations in UM may be more dependent on ethnicity and demographic variables than hitherto considered.

Background: The standard of care in patients with suspected prostate cancer (PCa) is systematic prostate biopsies. This approach leads to unnecessary biopsies in patients without PCa and also to the detection of clinical insignificant PCa. Better tools are wanted. We have evaluated the performance of real-time elastography (RTE) combined with prostate cancer gene 3 (PCA3) in an initial biopsy setting with the goal of better identifying patients in need of prostate biopsies. Methods: 127 patients were included in this study; three were excluded because of not measureable PCA3 score leading to 124 evaluable patients. A cut-off value of 35 was used for PCA3. All patients were examined with a Hitachi Preirus with an endfire probe for RTE, a maximum of five targeted biopsies were obtained from suspicious lesions detected by RTE. All patients then had a 10-core systematic biopsy performed by another urologist unaware of the RTE results. The study includes follow-up data for a minimum of three years; all available histopathological data are included in the analysis. Results: There was a significant difference in PCA3 score: 26.6 for benign disease, 73.6 for cancer patients (p

Background and objectives: Testicular Leydig cell tumours (LCTs) are rare, steroid-secreting tumours. Elevated levels of aromatase (CYP19 or CYP19A1) mRNA have been previously described in LCTs; however, little is known about the mechanism(s) causing CYP19 over-expression. We report an LCT in a 29-year-old male with elevated plasma oestradiol caused by enhanced CYP19 transcription. Design and methods: First, we measured the intra-tumour expression of CYP19 and determined the use of CYP19 promoters by qPCR. Secondly, we explored CYP19 and promoter II (PII) for gene amplifications and activating mutations in PII by sequencing. Thirdly, we analysed intra-tumour expression of steroidogenic factor 1 (SF-1 (NR5A1)), liver receptor homologue-1 (LRH-1 (NR5A2)) and cyclooxygenase-2 (COX2 (PTGS2)). Finally, we analysed SF-1 for promoter mutations and gene amplifications. Results: Similar to what has been recorded in normal Leydig cells, we first found the bulk of tumour CYP19 transcripts to be PII derived, excluding promoter shift as a cause of enhanced transcription. Secondly, we excluded CYP19 and PII gene amplifications, and activating mutations in PII, as causes of elevated CYP19 mRNA. We found SF-1 mRNA to be up-regulated in the tumour, while LRH-1 and COX2 were down-regulated. The finding of elevated SF-1 levels in the tumour was confirmed by immunohistochemistry. The elevated level of SF-1 was not due to promoter mutations or amplifications of the SF-1 gene. Conclusions: Our results strongly suggest that the elevated levels of SF-1 have induced PII-regulated CYP19 transcription in this tumour. These findings are of relevance to the understanding of CYP19 up-regulation in general, which may occur in several tissues, including breast cancer.

Metastatic tumors can prepare a distant site for colonization via the secretion of factors that act in a systemic manner. We hypothesized that non- or weakly metastatic human tumor cells may act in an opposite fashion by creating a microenvironment in distant tissues that is refractory to colonization. By comparing cell lines with different metastatic potential, we have identified a tumor-secreted inhibitor of metastasis, prosaposin (Psap), which functions in a paracrine and endocrine fashion by stimulating the expression of thrombospondin-1 (Tsp-1) in fibroblasts present in both primary tumors and distant organs, doing so in a p53-dependent manner. Introduction of Psap in highly metastatic cells significantly reduced the occurrence of metastases, whereas inhibition of Psap production by tumor cells was associated with increased metastatic frequency. In human prostate cancer, decreased Psap expression was significantly associated with metastatic tumors. Our findings suggest that prosaposin, or other agents that stimulate p53 activity in the tumor stroma, may be an effective therapy by inhibition of the metastatic process.

Background: High-risk human papilloma virus (HPV) infection is associated with the carcinogenesis in head and neck squamous carcinoma (HNSCC), especially in oropharynx . Several molecular and clinical studies have revealed that the molecular alternation in HPV(+) tumors is greatly differ from HPV(-) tumors, and the patients with HPV(+) tumors have favorable prognosis. While cetuximab, a monoclonal antibody of against epidermal growth factor receptor (EGFR), has been shown to increase survival in HNSCC , the possible correlation between cetuximab response and HPV status has not been examined. In this study, we investigated the correlation between sensitivity to cetuximab and HPV status in HNSCC cell lines in vivo and in vitro, and examined a novel class of anti-cancer drugs that would specifically target the HPV(+) tumors based on the gene expression and the Connectivity Map analyses. Experimental design: The HPV status of three HPV(+) HNSCC cell lines (UM-SCC47, UPCI-SCC090 and 93VU147T) and three HPV(-) cell lines (SQ20B, SCC61 and SCC25) were confirmed by PCR using L1- and E6-specific primers. The protein expression of EGFR and its downstream proteins, Akt and MAPK as well as their activation status were determined in pre- and post-cetuximab treated cell lysates by western blot analyses using total and phospho-specific antibodies The sensitivity to cetuximab in each cell line was evaluated by MTS assay in vitro and mouse xenograft model in vivo. Total RNA was isolated from each cell line pre- and post-treatment with cetuximab and analyzed for gene expression changes in triplicate using Affymetrix GeneChip. The differentially expressed genes comparing HPV(+) vs. HPV(-), and cetuximab sensitive vs. resistant were determined by supervised analyses. To identify a novel class of anti-cancer drugs that specifically target HPV(+), the HPV-specific signature was analyzed using Connecitivity Map. Results: The HPV status was confirmed in the six cell lines as expected. Among the six cell lines, SCC25 and SCC090 were highly sensitivite to cetuximab in vitro and in vivo assays independent of the HPV status. The gene signature associated with HPV status in the cell lines included cell cycle regulators (p16INK4A and p18), the cell adhesion molecule (TCAM1) and transcription factors (TAF7 andRPA2). These genes were also found in our previous study performed using human HNSCC tumor samples. The Connectivity Map analysis showed that the gene signature modulated by geldanamycin was highly associated with the HPV-related gene signature. Conclusion Our data suggest that HPV status is not associated with cetuximab sensitivity in HNSCC cell lines. Based on gene expression analyses, the HPV(+) cell lines have specific deregulation in the cell cycle regulation. Also, HPV(+) tumors may be targeted using a class of anti-cancer drugs, HSP90 inhibitors, such as geldanamycin which are already in clinical development in other cancer types. Citation Information: In: Proc Am Assoc Cancer Res; 2009 Apr 18-22; Denver, CO. Philadelphia (PA): AACR; 2009. Abstract nr 4708.

Purpose: Cell adhesion molecules are of crucial importance in cancer invasion and metastasis. Epithelial to mesenchymal transition, characterized by reduced E-cadherin and increased N-cadherin expression, has been recognized as a feature of aggressive tumors, but the importance of this phenotype has not been settled in human prostate cancer. We here present novel data, with special focus on the independent relationship between an E-cadherin to N-cadherin switch (EN-switch) and patient prognosis. Experimental Design: Tissue microarray sections from a consecutive series of 104 radical prostatectomies during 1988 to 1994 with detailed clinicopathologic data and long follow-up were studied immunohistochemically for the expression of E-cadherin, N-cadherin, P-cadherin, β-catenin, and p120CTN. Results: Low E-cadherin expression was significantly associated with adverse clinicopathologic features, whereas other biomarkers were mostly related to Gleason score. In univariate survival analyses, cadherin switching (high N-cadherin and low E-cadherin) showed strong and significant associations with multiple end points of progression and cancer-specific death. Expression of the “basal cell marker” P-cadherin was associated with shorter time to skeletal metastasis (P = 0.036). In multivariate analysis of time to clinical recurrence, the “EN-switch” (hazard ratio, 4.3; P < 0.0005) had strong and independent prognostic effect, together with Gleason score. Conclusion: These novel data unravel the importance of epithelial to mesenchymal transition for prostate cancer progression, and demonstration of a switch from E-cadherin to N-cadherin expression could have significant effect on the care of prostate cancer patients.

Background The use of multiparametric magnetic resonance imaging (mpMRI) to detect and localize prostate cancer has increased in recent years. In 2010, the European Society of Urogenital Radiology (ESUR) published guidelines for mpMRI and introduced the Prostate Imaging Reporting and Data System (PI-RADS) for scoring the different parameters. Purpose To evaluate the reliability and diagnostic performance of endorectal 1.5-T mpMRI using the PI-RADS to localize the index tumor of prostate cancer in patients undergoing prostatectomy. Material and Methods This institutional review board IRB-approved, retrospective study included 63 patients (mean age, 60.7 years, median PSA, 8.0). Three observers read mpMRI parameters (T2W, DWI, and DCE) using the PI-RADS, which were compared with the results from whole-mount histopathology that analyzed 27 regions of interest. Inter-observer agreement was calculated as well as sensitivity, specificity, positive predictive value (PPV), and negative predicted value (NPV) by dichotomizing the PI-RADS criteria scores ≥3. A receiver-operating curve (ROC) analysis was performed for the different MR parameters and overall score. Results Inter-observer agreement on the overall score was 0.41. The overall score in the peripheral zone achieved sensitivities of 0.41, 0.60, and 0.55 with an NPV of 0.80, 0.84, and 0.83, and in the transitional zone, sensitivities of 0.26, 0.15, and 0.19 with an NPV of 0.92, 0.91, and 0.92 for Observers 1, 2, and 3, respectively. The ROC analysis showed a significantly increased area under the curve (AUC) for the overall score when compared to T2W alone for two of the three observers. Conclusion 1.5 T mpMRI using the PI-RADS to localize the index tumor achieved moderate reliability and diagnostic performance.

Endobronchial ultrasonography (EBUS) using balloon-embedded probes may cause airway obstruction and requires a rapid scanning procedure. Three-dimensional (3-D) postprocessing of sequential 2-D images may allow detailed studies on a rapidly acquired image volume. We applied a 3-D reconstruction program on EBUS recordings acquired with a radial-scanning probe during a controlled pullback procedure in water-filled airways in five corpses. The aim was to acquire EBUS images under optimized conditions and to test a 3-D software program for postprocessing. Under post mortem conditions, 3-D images were obtained, allowing any-plane imaging and measurements, application of different rendering and visualization algorithms and merging of overlapping volumes.

The aim of this study was to test the ability of prostate cancer antigen-3 (PCA3) and Hansen's PCA3-based nomogram to predict prostate cancer (PCa) probability in a Norwegian cohort, with the goal of reducing unnecessary biopsies.Altogether, 127 consecutive patients were recruited to this study at Haukeland University Hospital, Norway. Prostate-specific antigen (PSA), PCA3 score, digital rectal examination (DRE), prostate volume (Pvol) and age were determined. All patients had an extended 10-core biopsy. The performance of PCA3 score and Hansen's nomogram was tested.There were 124 evaluable patients. Among these, 59 patients had PCa on the initial biopsies. Mean PSA, PCA3 score and age were significantly higher and Pvol was significantly lower in patients with PCa. PCA3 scores of 35 and 21 led to a sensitivity of 71% and 81% and specificity of 72% and 55%, respectively. Hansen's nomogram gave an area under the curve (AUC) of 0.806. The intraclass correlation was 0.959 (Cronbach's alpha). Applied to this material, PCa would be missed in 15.2% of patients when applying the suggested threshold probability of 30%, among whom 66.7% had high-grade PCa. With a threshold probability of 20% only one patient had PCa and this was low grade.Hansen's PCA3-based nomogram is valid for this cohort. A threshold probability of 20% seems more adequate than 30% for this less screened cohort. PCA3 score only affects the biopsy indication in some patients and is recommended only for this subset. The results need to be confirmed in a larger study.

To evaluate the performance of real-time elastography (RTE) in an initial biopsy setting.In the period from February 2011 to June 2012, 127 consecutive patients were included in the study. We used a Hitachi Preirus with Hi-RTE module, a prostate end-fire transrectal probe was used for RTE and for targeted biopsies, and a simultaneous biplane probe was used for the standard systematic biopsies. The peripheral zone of the prostate was divided into six regions, and each biopsy obtained was referred to a specific region. All patients were first examined with RTE and, if cancer was suspected, targeted biopsies were taken. A standard systematic 10-core biopsy was then taken in all patients.In all, 64 (50%) patients were diagnosed with prostate cancer in the initial biopsy setting. Three patients were diagnosed solely on RTE-targeted biopsies, 31 were found only in systematic biopsies, and 30 were correctly diagnosed with both methods. In the RTE-positive group there was a significantly higher frequency of positive cores, a lower prostate volume, a higher Gleason score, and a higher fraction of cancer tissue in each core. In a multiple regression model RTE was an independent marker for high-risk cancer. The sensitivity of 42% for all prostate cancers increased to 60% for high-grade prostate cancers. Similarly, the negative predictive value increased from 79% to 97%. An additional eight patients were diagnosed with prostate cancer during the study period.A positive RTE is an independent marker for detection of high-risk prostate cancer, and a negative RTE argues against such. RTE with targeted biopsies cannot replace systematic biopsies, but provides valuable additional information about the tumours.

s: AACR Special Conference on Tumor Metastasis; November 30-December 3, 2015; Austin, TX Ovarian cancer is the most lethal gynecologic malignancy and the fourth leading cause of cancer deaths in women. Pathologically, ovarian cancer is categorized into multiple subtypes, with epithelial ovarian cancer (EOC) representing 90% of cases. Despite our increased understanding of the biology governing the progression of EOC the survival rate for patients with stage IV EOC is only 17%. The vast majority of ovarian cancer-related deaths are caused by metastatic dissemination of cells from the primary tumor resulting in subsequent organ failure. Tragically, there are no clinically approved drugs that have shown significant efficacy at treating advanced, metastatic, ovarian cancer. As such, there is a dire need for efficacious therapies that can specifically treat advanced, metastatic ovarian cancer. We were the first to identify prosaposin (psap) as a potent inhibitor of tumor metastasis via stimulation of the anti-tumorigenic protein thrombospondin-1 (Tsp-1) in bone marrow-derived cells that are recruited to metastatic sites. We report here that virtually 100% of human serous ovarian tumors tested express CD36, the receptor that mediates the pro-apoptotic activity of Tsp-1. Accordingly, we developed a novel cyclic peptide with drug-like properties derived from the active sequence in psap. Strikingly, this cyclic psap peptide was able to significantly regress metastatic tumors in a patient-derived tumor xenograft (PDX) model of metastatic ovarian cancer. Thus, our findings suggest that development of a therapeutic agent based on this psap peptide would have significant efficacy in treating patients with metastatic ovarian cancer. Citation Format: Suming Wang, Anna Blois, Tina EI Rayes, Joyce F. Liu, Michelle S. Hirsch, Karsten Gravdal, Diane R. Bielenberg, Lars A. Akslen, Ronny Drapkin, Vivek Mittal, Randolph S. Watnick. Development of a novel peptide therapeutic that targets ovarian cancer via the tumor microenvironment. [abstract]. In: Proceedings of the AACR Special Conference on Tumor Metastasis; 2015 Nov 30-Dec 3; Austin, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(7 Suppl):Abstract nr A18.

The prostate cancer gene 3 (PCA3) score in urine is a promising biomarker for prostate cancer. Real-time elastography (RTE) is a well-documented ultrasound modality. The objective of this study was to evaluate the ability to detect significant cancer foci in the prostate with these methods alone and in combination.From September 2009 to September 2010, 40 patients planned for radical prostatectomy underwent a PCA3 urine test and RTE before operation. A Hitachi EUB-8500 with prostate end-fire transrectal probe was used. The PCA3 score was evaluated with a standard cut-off value of 35. RTE was evaluated in correlation with whole-mount section pathology. Three patients fulfilled the criteria for insignificant prostate cancer and were excluded from the study.The PCA3 score was increased in 26 patients (70%). RTE identified at least one tumour in 33 out of 37 patients (89%). RTE detected the largest tumour in 27 out of 37 patients (73%). More than one cancer was present in 29 patients and RTE identified more than one tumour in 13 of these. The RTE was false positive in four patients. The PCA3 score was increased in three out of four false-negative RTE patients. By combining both methods, 36 out of 37 patients (97%) with significant prostate cancer were detected.The combination of PCA3 score and RTE detected 97% of significant prostate cancers. The combinative use of RTE and PCA3 will be further investigated in an unselected series of men with suspected prostate cancer.

Background: Enhancer of zeste homologue 2 (EZH2) is a member of the Polycomb group of genes that is involved in epigenetic silencing and cell cycle regulation.Methods: We studied EZH2 expression in 409 patients with colorectal cancer stages II and III. The patients were included in a randomised study, and treated with surgery alone or surgery followed by adjuvant chemotherapy.Results: EZH2 expression was significantly related to increased tumour cell proliferation, as assessed by Ki-67 expression. In colon cancer, strong EZH2 expression (P=0.041) and high proliferation (greater than or equal to 40%; P=0.001) were both associated with better relapse-free survival (RFS). In contrast, no such associations were found among rectal cancers. High Ki-67 staining was associated with improved RFS in colon cancer patients who received adjuvant chemotherapy (P=0.001), but not among those who were treated by surgery alone (P=0.087). In colon cancers stage III, a significant association between RFS and randomisation group was found in patients with high proliferation (P=0.046), but not in patients with low proliferation (P=0.26). Multivariate analyses of colon cancers showed that stage III (hazard ratio (HR) 4.00) and high histological grade (HR 1.80) were independent predictors of reduced RFS, whereas high proliferation indicated improved RFS (HR 0.55).Conclusion: Strong EZH2 expression and high proliferation are associated features and both indicate improved RFS in colon cancer, but not so in rectal cancer.

Purpose: Prostate cancer is the third leading cause of cancer death in the United States, following lung and colorectal cancer. We previously identified WDR19 as a prostate-specific, androgen-regulated gene. Here, we evaluate its utility as a prostate cancer tissue marker for diagnosis and prognostic evaluation. Experimental Design: Real-time quantitative PCR was done on a panel of prostate tissue isolated by laser capture microdissection. After generating antibodies against WDR19, tissue microarrays (TMA) were employed to compare WDR19 expression between normal, benign prostatic hyperplasia, and prostate cancer tissue. Results: Using microarrays and real-time quantitative PCR, we showed that WDR19 mRNA expression was increased in cancer. We further showed that WDR19 protein is localized to cytoplasmic subcellular granules and is expressed exclusively in prostate epithelia. Large-scale immunohistochemical staining using TMAs reveals a significant percentage of increase in intensely staining tissue cores in cancer tissue when compared with normal or benign prostatic hyperplastic tissue. Based on the analysis of a separate TMA for which clinical follow-up information was available, low-intensity WDR19 staining was significantly associated with decreased time to biochemical failure (P = 0.006) and with decreased time to locoregional recurrence (P = 0.050). Conclusions: WDR19 should be added to the list of prostate cancer tissue markers. The continued expansion of a multiple-marker panel will conceivably increase the sensitivity and specificity of prostate cancer diagnosis and prognosis.

Microvessel density (MVD) has been associated with progression of prostate cancer. Although basic fibroblast growth factor (bFGF) is a known endothelial mitogen, the prognostic role of bFGF and its receptor FGFR-1 in prostate cancer has been controversial. The aim of our study was to examine the tissue distribution and prognostic significance of bFGF, FGFR-1, and microvascular proliferation. Sections from 104 radical prostatectomy specimens were examined by factor VIII/Ki-67 staining for proliferating capillary index (PCI) and MVD, and tissue microarray sections were immunostained for bFGF and FGFR-1. Increased PCI (median 0.49%) was related to strong stromal expression of bFGF (P=0.003) but was without prognostic impact. Strong bFGF staining was associated with well-differentiated tumors, no capsular penetration, low serum-prostate-specific antigen (s-PSA), low tumor cell proliferation, and increased time to biochemical failure (P=0.007), and was of independent prognostic importance in multivariate survival analysis. bFGF expression in vessels was associated with low MVD (P=0.0003). In contrast, strong tumor cell FGFR-1 expression was related to high preoperative s-PSA. Thus, increased stromal and vessel bFGF was associated with less aggressive tumors. Our findings indicate a complex relationship between bFGF/FGFR-1 expression and prognosis of prostate cancer. Vascular proliferation revealed no prognostic impact in this study.

Previous studies have shown that metastatic tumors establish premetastatic niches comprised of recruited bone marrow (BM)-derived cells in potential distant target metastatic organs. These premetatatic niches serve as permissive hubs for supporting future metastases. However, little is known about whether tumors that lack metastatic potential establish such niches, or generate niches that inhibit metastasis. Here, we show that metastasis-incompetent tumors are also capable of systemically generating BM-derived niches in the metastatic organs. However, by secreting the glycoprotein prosaposin these tumors systemically stimulate expression of antitumorigenic factor thrombospondin-1 (Tsp-1) in the Gr1+ myeloid cells converting them it into a metastasis-refractory niche. Genetic deletion of Tsp-1 abolished the inhibition of metastasis, which was restored by BM transplant from Tsp-1+ donors. We developed a 5-amino acid peptide from prosaposin as a pharmacological inducer of Tsp-1 in Gr1+ BM cells. Strikingly, the peptide suppresses metastasis. These results provide mechanistic insights into why certain tumors are deficient in metastatic potential and implicate recruited Gr1+ myeloid cells as the main source of Tsp-1, contrary to previous notion. These results also underscore the plasticity of Gr1+ cells, which, depending on the context and the nature of paracrine factor/s can either promote or inhibit metastasis. Clinically, examination of a tumor tissue microarray (TMA) compiled from 103 prostate cancer patients with long and complete follow up, revealed that prosaposin expression positively correlated with increased overall survival, suggesting that the prosaposin peptide may be a potential therapeutic agent against metastatic cancer. Citation Format: Raul Catena, Nandita Bhattacharya, Tina El Rayes, Hyejin Choi, Suming Wang, Dingcheng Gao, Natasha Joshi, Seongho Ryu, Diane Bielenberg, Sharrell Lee, Svein Haukaas, Karsten Gravdal, Ole Halvorsen, Lars Akslen, Randolph Watnick, Vivek Mittal. Bone marrow-derived Gr1+ cells can generate a metastasis-resistant microenvironment via induced secretion of thrombospondin-1. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4584. doi:10.1158/1538-7445.AM2013-4584

Genome-wide gene expression analysis identified p63 as one of the most consistently under-expressed transcription factors in prostate cancer samples compared to matched benign prostate tissue. Two alternative p63 promoters generate two different N-terminal variants, TA or ΔN which contains and lacks the transactivating domain, respectively. Differential splicing generates multiple additional isoforms. The activity and interactions of the different isoforms remain unresolved. Isoform-specific real-time quantitative PCR assays revealed that ΔNp63α is the predominant isoform in epithelial prostate tissues, but other isoforms are detectable. Our group has established an experimental cell culture model based upon primary, immortalized prostate epithelial cells (EP156T cells), where p63 was shut down when EP156T cells underwent epithelial-to-mesenchymal transition (EMT) to become EPT1 cells. Subsequently, several additional mesenchymal like cell subtypes with additional malignant features, including anchorage independent growth in soft agar and ability to grow at much higher density in monolayers, were derived from EPT1 cells. All of these subtypes exhibited very low p63 expression. To examine the potential of p63 to induce mesenchymal to epithelial transition (MET) in this EMT model, we have stably re-expressed the ΔNp63α and TAp63α isoforms in different mesenchymal like cells of the model using retroviral/lentiviral vector transductions. Genome-wide gene expression analyses and phenotypic cellular assays revealed that the ΔNp63α isoform induced re-expression of multiple genes involved in cell adhesion. But this was not associated with complete MET induction. Cells re-expressing ΔNp63α obtained an intermediate morphology with both epithelial and mesenchymal traits, and with actin filaments organized in stress fibers. ΔNp63α re-expression significantly compromised migratory but not invasive ability of the cells. Based upon these findings we want to investigate whether p63 may compromise epithelial to mesenchymal plasticity in an animal model of tumorigenic cells and if there is differential effect on primary tumor growth compared to metastatic growth. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1290. doi:1538-7445.AM2012-1290

A family of transcription factors is constituted by p53, p63 and p73. Unlike p53, which is expressed in response to environmental stress, p63 (TP73L) is constitutively expressed at high levels in a variety of epithelial tissues including prostate. Our genome-wide gene expression analysis identified p63 as one of the most consistently under-expressed genes in prostate cancer samples compared to matched benign prostate tissue. All benign prostate samples including benign prostate hyperplasias (BPH) exhibited high p63 expression. Two alternative p63 promoters generate two different N-terminal variants, TA or ΔN which contains and lacks the transactivating domain, respectively. Differential splicing generates multiple additional isoforms. The activity and interactions of the different isoforms remain unresolved. Using isoform-specific TaqMan real-time quantitative PCR assays, we have found that ΔNp63α is the predominant isoform in prostate tissues, but the other isoforms are detectable. Our group has established a new experimental cell culture model based upon primary, immortalized prostate epithelial cells (EP156T cells), where p63 was found to be shut-down as EP156T cells underwent epithelial-to-mesenchymal transition (EMT) to become EPT1 cells. Subsequently, EPT2 cells were derived from EPT1 cells and p63 stayed shut-down. EPT2 cells had acquired several malignant features in contrast to the progenitors, including anchorage independent growth in soft agar and ability to grow at much higher density in monolayers. To dissect the role of p63 in EMT and in gene expression modules associated with carcinogenesis, we have stably re-expressed the predominant isoform ΔNp63α in both EPT1 and EPT2 cells using retroviral vector transductions. Microarray analysis shows that p63 re-expression leads to re-expression of genes participating in several cell-junction components, such as hemidesmosomes, focal adhesions and gap junctions. These genes were down-regulated during EMT. There were also morphological changes and a decreased ability to migrate following p63 re-expression. This indicates that ΔNp63α re-expression might result in a partial mesenchymal-to-epithelial transition (MET). The present focus is to identify co-factors that may act complementary or synergetically with p63 to induce a complete MET in EPT1 cells and to identify p63 target genes and regulatory cross-talk with relevance for anti-cancer strategies. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 3089. doi:10.1158/1538-7445.AM2011-3089