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Purpose: The epithelial-to-mesenchymal transition (EMT) is a cell development-regulated process in which noncoding RNAs act as crucial modulators. Recent studies have implied that EMT may contribute to resistance to epidermal growth factor receptor (EGFR)–directed therapy. The aims of this study were to determine the potential role of microRNAs (miRNA) in controlling EMT and the role of EMT in inducing the sensitivity of human bladder cancer cells to the inhibitory effects of the anti-EGFR therapy.Experimental Design: miRNA array screening and real-time reverse transcription-PCR were used to identify and validate the differential expression of miRNAs involved in EMT in nine bladder cancer cell lines. A list of potential miR-200 direct targets was identified through the TargetScan database. The precursor of miR-200b and miR-200c was expressed in UMUC3 and T24 cells using a retrovirus or a lentivirus construct, respectively. Protein expression and signaling pathway modulation, as well as intracellular distribution of EGFR and ERRFI-1, were validated through Western blot analysis and confocal microscopy, whereas ERRFI-1 direct target of miR-200 members was validated by using the wild-type and mutant 3′-untranslated region/ERRFI-1/luciferse reporters.Results: We identified a tight association between the expression of miRNAs of the miR-200 family, epithelial phenotype, and sensitivity to EGFR inhibitors–induced growth inhibition in bladder carcinoma cell lines. Stable expression of miR-200 in mesenchymal UMUC3 cells increased E-cadherin levels, decreased expression of ZEB1, ZEB2, ERRFI-1, and cell migration, and increased sensitivity to EGFR-blocking agents. The changes in EGFR sensitivity by silencing or forced expression of ERRFI-1 or by miR-200 expression have also been validated in additional cell lines, UMUC5 and T24. Finally, luciferase assays using 3′-untranslated region/ERRFI-1/luciferase and miR-200 cotransfections showed that the direct down-regulation of ERRFI-1 was miR-200-dependent because mutations in the two putative miR-200-binding sites have rescued the inhibitory effect.Conclusions: Members of the miR-200 family appear to control the EMT process and sensitivity to EGFR therapy in bladder cancer cells and the expression of miR-200 is sufficient to restore EGFR dependency at least in some of the mesenchymal bladder cancer cells. The targets of miR-200 include ERRFI-1, which is a novel regulator of EGFR-independent growth. (Clin Cancer Res 2009;15(16):5060–72)

Conflict of Interest Form 1 from miR-200 Expression Regulates Epithelial-to-Mesenchymal Transition in Bladder Cancer Cells and Reverses Resistance to Epidermal Growth Factor Receptor Therapy

Emerging data suggests improved outcomes in patients receiving neoadjuvant chemotherapy (NAC) prior to radical nephroureterectomy (RNU) for high-risk upper tract urothelial carcinoma. In one of the largest single-center experiences to date, we provide an updated analysis of outcomes of patients receiving NAC followed by RNU.A retrospective review of patients with high-risk UTUC who received NAC followed by surgery between 2004 to 2017 was conducted. 126 patients were evaluated as part of the analysis. Kaplan-Meier method was used to estimate survival probabilities. Multivariable Cox modeling was used to evaluate for association with outcomes, and the cumulative incidence factor was used for competing risk analysis.Median OS time was 106 months. 14.3% of patients had a pathologic complete response and 60% were down-staged to ypT0-1 ypN0. The estimated 5 and 10-year DSS rates were 89.8% and 80.6%, respectively. The estimated 5 and 10-year metastasis-free survival rates were 81% and 75.4%, respectively. The estimated 5 and 10-year OS rates were 73.7% and 35.9 %, respectively. Recurrences mainly occurred in lymph nodes and lung at a median time of 15.5 months (IQR 8.9-27). The estimated 5 and 10-year cumulative incidence factor for death from UTUC was 9.5% and 16.1%, respectively. Limitations include retrospective nature and challenge of accurate pre-surgical staging.NAC prior to RNU in high-risk UTUC shows durable 5 and 10-year OS and DSS rates in a large single-institution series, confirming prior findings in prospective trials and retrospective studies.

Summary: Sarcomatoid urothelial bladder cancer (SARC) displays a high propensity for distant metastasis and is associated with short survival. We report a comprehensive genomic analysis of 28 cases of SARC and 84 cases of conventional urothelial carcinoma (UC), with the TCGA cohort of 408 muscle-invasive bladder cancers serving as the reference. SARCs show a distinct mutational landscape, with enrichment of TP53, RB1, and PIK3CA mutations. They are related to the basal molecular subtype of conventional UCs and could be divided into epithelial-basal and more clinically aggressive mesenchymal subsets on the basis of TP63 and its target gene expression levels. Other analyses reveal that SARCs are driven by downregulation of homotypic adherence genes and dysregulation of the EMT network, and nearly half exhibit a heavily infiltrated immune phenotype. Our observations have important implications for prognostication and the development of more effective therapies for this highly lethal variant of bladder cancer. : Guo et al. report that sarcomatoid carcinoma of the bladder evolves by the progression of the basal subtype of conventional urothelial carcinoma with the enrichment of mutagenesis signature 1 and mutations of TP53, RB1, and PIK3CA. It is driven by the dysregulation of the EMT network and shows increased immune infiltrate with overexpression of PD-L1. Keywords: bladder cancer, sarcomatoid carcinoma, urothelial carcinoma, epithelial-mesenchymal transformation, genomic expression, chromatin remodeling, microRNA expression, molecular classification, basal subtype, immune phenotype

Muscle-Invasive Bladder Cancer (MIBC) is a molecularly diverse disease with heterogeneous clinical outcomes. Several molecular classifications have been proposed, yielding diverse sets of subtypes, which hampers the clinical implications of such knowledge. Here, we report the results of a large international effort to reach a consensus on MIBC molecular subtypes. Using 1750 MIBC transcriptomes and a network-based analysis of six independent MIBC classification systems, we identified a consensus set of six molecular classes: Luminal Papillary (24%), Luminal Non-Specified (8%), Luminal Unstable (15%), Stroma-rich (15%), Basal/Squamous (35%), and Neuroendocrine-like (3%). These consensus classes differ regarding underlying oncogenic mechanisms, infiltration by immune and stromal cells, and histological and clinical characteristics. This consensus system offers a robust framework that will enable testing and validating predictive biomarkers in future clinical trials.

SUMMARYThe sarcomatoid variant of urothelial bladder cancer (SARC) displays a high propensity for distant metastasis and is associated with short survival. We report a comprehensive genomic analysis of 28 cases of SARCs and 84 cases of conventional urothelial carcinomas (UCs), with the TCGA cohort of 408 muscle-invasive bladder cancers serving as the reference. SARCs showed a distinct mutational landscape with enrichment ofTP53, RB1, and PIK3CAmutations. They were related to the basal molecular subtype of conventional UCs and could be divided into epithelial/basal and more clinically aggressive mesenchymal subsets based on TP63 and its target genes expression levels. Other analyses revealed that SARCs are driven by downregulation of homotypic adherence genes and dysregulation of cell cycle and EMT networks, and nearly half exhibited a heavily infiltrated immune phenotype. Our observations have important implications for prognostication and the development of more effective therapies for this highly lethal variant of bladder cancer.

Type I interferon (IFN) has potent antitumor effects in bladder cancer and provides an essential alternative treatment option for patients who do not respond to Bacillus Calmette-Guerin (BCG). However, the mechanism of the IFN-stimulated immune response in bladder cancer is not well understood. We hypothesized that type I IFN enhances recruitment and activation of immune cells in murine bladder cancer tumors, and makes them more responsive to anti-PD-1 mAb therapy. To incite an IFN-driven inflammatory response, poly(I:C) was given to murine MB49 bladder cancer tumors peritumorally alone and in combination with anti-PD-1 mAb to determine effects on tumor growth and animal survival. IFN induction in MB49 tumors significantly inhibited tumor growth. This response was reliant on both innate and adaptive immune subsets, shown in the increased influx of intratumoral Ly6G+ neutrophils and the increase in IFNy+CD8 T cells. In addition, depleting specific immune cell subsets indicated that no one type of immune cell was critical for the IFN-mediated anti-tumor response. When used in combination with anti-PD-1 mAb, poly(I:C) prolonged mouse survival and enriched gene pathways involved in metabolism, extracellular matrix formation and organization, and PI3K and AKT signaling. To examine effects of IFN-I in BCG-unresponsive patients, tumor samples were analyzed for RNA expression and immunohistochemical (IHC) staining both before and after treatment with adenoviral interferon-α. Among these samples, 25% showed increased expression of T cell and checkpoint markers, similarly reflected in IHC analysis. Our findings suggest type I IFN grooms the tumor-immune landscape in bladder cancer by activating both innate and adaptive immune cells.

A phase l study using intravesical Ad-IFNαSyn3 for patients with bacillus Calmette-Guerin-resistant superficial bladder cancer showed a complete remission (CR) of 43% at 90 days after treatment with high levels of interferon-α (IFNα) being produced. Ad-IFNα kills bladder cancer cells by two apoptotic and one necrotic mechanism that can be measured by soluble forms of cytokeratin 18 (CK18) using M30 and M65 ELISAs, assays for caspase-cleaved (apoptotic) and uncleaved (necrotic) cell death, respectively. Therefore, we determined whether M30 and M65 levels in the urine after treatment could document all three mechanisms of cancer cell kill and also predict having a CR. High levels of both M30 and M65 were found in all patients within 24 h after treatment with all three types of cancer cell death occurring. Moreover, the return of both M30 and M65 levels in the urine to normal levels within 5 days or more after treatment was strongly associated with obtaining a CR (P=0.003). This is the first time that such assays have been used to study response to therapy in the urine of patients with bladder cancer and in the future may prove valuable in predicting clinical outcome.

This study compares urine nuclear matrix protein 22 (NMP22) immunoassay and conventional urine cytologic examination for detecting recurrent transitional-cell carcinoma (TCC) of the urinary bladder. One hundred twenty-eight urine specimens from 107 patients with a history of TCC of the urinary bladder were studied. NMP22 immunoassay and conventional cytologic examination were performed on each specimen. The NMP22 and cytology results were then compared with the results of subsequent cystoscopies/surgical biopsies performed over a 6-mo follow-up period. The sensitivity of urine cytologic study for predicting recurrent TCC was 60%, while the sensitivity of NMP22 assay was 47%. When both NMP22 assay results and the cytologic interpretation were positive for TCC, the positive predictive value of the combined tests was 74%. When both tests showed negative results, the negative predictive power was 81%. Our findings suggest that urine NMP22 assay may represent a useful diagnostic adjunct to conventional urine cytologic examination for the detection of recurrent TCC of the urinary bladder.

Epithelial-mesenchymal transition (EMT) is a physiological process that plays important roles in tumor metastasis, "stemness," and drug resistance. EMT is typically characterized by the loss of the epithelial marker E-cadherin and increased expression of EMT-associated transcriptional repressors, including ZEB1 and ZEB2. The miR-200 family and miR-205 prevent EMT through suppression of ZEB1/2. p53 has been implicated in the regulation of miR-200c, but the mechanisms controlling miR-205 expression remain elusive. Here we report that the p53 family member and p63 isoform, ΔNp63α, promotes miR-205 transcription and controls EMT in human bladder cancer cells. ΔNp63α, E-cadherin and miR-205 were coexpressed in a panel of bladder cancer cell lines (n = 28) and a cohort of primary bladder tumors (n = 98). Stable knockdown of ΔNp63α in the "epithelial" bladder cancer cell line UM-UC6 decreased the expression of miR-205 and induced the expression of ZEB1/2, effects that were reversed by expression of exogenous miR-205. Conversely, overexpression of ΔNp63α in the "mesenchymal" bladder cancer cell line UM-UC3 induced miR-205 and suppressed ZEB1/2. ΔNp63α knockdown reduced the expression of the primary and mature forms of miR-205 and the miR-205 "host" gene (miR-205HG) and decreased binding of RNA Pol II to the miR-205HG promoter, inhibiting miR-205HG transcription. Finally, high miR-205 expression was associated with adverse clinical outcomes in bladder cancer patients. Together, our data demonstrate that ΔNp63α-mediated expression of miR-205 contributes to the regulation of EMT in bladder cancer cells and identify miR-205 as a molecular marker of the lethal subset of human bladder cancers.

Over the past several years we have obtained considerable evidence indicating that adenoviruses-expressing interferon α (Ad-IFNα) can overcome resistance to the IFNα protein itself. Since cancer cells infected with Ad-IFNα also show high perinuclear cytoplasmic IFNα expression, we were interested in whether endoplasmic reticulum (ER) stress and cleavage of caspase 4 could have a major role in Ad-IFNα-produced cancer cell death. Indeed, procaspase 4 was upregulated and cleaved as early as 12 h after Ad-IFNα infection of the cancer cells, which co-localized with IFNα staining and ER tracker. In contrast, immortalized normal human urothelial cells, although exhibiting similar perinuclear IFNα staining, showed no cleaved caspase 4. Caspase 4 cleavage was not blocked by the caspase 8 specific inhibitor zIETD, indicating that caspase 4 activation was independent of caspase 8 activation. Blocking caspase 4 also inhibited activation of caspase 3 in Ad-IFNα containing cells. Finally, the cleaved form of caspase 4 (p10) was detected in Ad-IFNα-positive cancer cells from the urine of a patient following intravesical Ad-IFNα/Syn3 treatment. Therefore, ER stress and activation of caspase 4 appears to be an important mechanism involved in the direct cancer cell death produced by Ad-IFNα and also occurs in the clinical setting.

We developed a strategy that combines histologic and genetic mapping that permits interrogation of the chronology of genetic changes associated with cancer development on a whole-organ scale. By using this approach, we analyzed the sequence of genetic alterations contiguous to the tumor suppressor RB1 and identified a set of alternative target genes that we term “forerunner” (FR) genes whose silencing was associated with development of clonal plaque-like mucosal field effects initiating bladder carcinogenesis. Expression and methylation studies identified five candidate FR genes (ITM2B, LPAR6, MLNR, CAB39L, and ARL11). In vitro mechanistic studies demonstrated that three of these genes (ITM2B, LPAR6 and ARL11) control cell survival and proliferation consistent with their loss of function being contributory to tumorigenesis, and in vivo genetic ablation of Lpar6 in a mouse model resulted in activation of basal/stem cell transcriptional programs involving STAT3 and NFκB causing proliferative expansion of the basal layer of the urothelium. Whole genome analyses of the field effects in a representative whole-organ map revealed a sequential accumulation of alterations in RHO/RAC/Cdc42 pathways that control invasion and cell motility. These studies identify FR genetic alterations in tissue fields as one of the earliest events in carcinogenesis and provide comprehensive description of field cancerization in a primary human tumor. The results have important implications for the development of novel detection markers and chemoprevention therapeutic strategies. Citation Format: Bogdan A. Czerniak, Sangkyou Lee, Jolanta Bondaruk, Sooyong Lee, Tadeusz Majewski, Shizhen Zhang, Li Shen, Yuexin Liu, Charles Guo, Colin Dinney, H. Barton Grossman, Wei Zhang, Menashe Bar-Eli, Keith Baggerly, Richard Behringer, David McConkey, David McConkey, Margaret Knowles, Woonbok Chung, Jean-Pierre Issa. Mechanism of field cancerization. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5256. doi:10.1158/1538-7445.AM2014-5256