Colin P. Dinney

Identification of Distinct Basal and Luminal Subtypes of Muscle-Invasive Bladder Cancer with Different Sensitivities to Frontline Chemotherapy

Muscle-invasive bladder cancers (MIBCs) are biologically heterogeneous and have widely variable clinical outcomes and responses to conventional chemotherapy. We discovered three molecular subtypes of MIBC that resembled established molecular subtypes of breast cancer. Basal MIBCs shared biomarkers with basal breast cancers and were characterized by p63 activation, squamous differentiation, and more aggressive disease at presentation. Luminal MIBCs contained features of active PPARγ and estrogen receptor transcription and were enriched with activating FGFR3 mutations and potential FGFR inhibitor sensitivity. p53-like MIBCs were consistently resistant to neoadjuvant methotrexate, vinblastine, doxorubicin and cisplatin chemotherapy, and all chemoresistant tumors adopted a p53-like phenotype after therapy. Our observations have important implications for prognostication, the future clinical development of targeted agents, and disease management with conventional chemotherapy.

miR-200 Expression Regulates Epithelial-to-Mesenchymal Transition in Bladder Cancer Cells and Reverses Resistance to Epidermal Growth Factor Receptor Therapy

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)

STAGE SPECIFIC GUIDELINES FOR SURVEILLANCE AFTER RADICAL NEPHRECTOMY FOR LOCAL RENAL CELL CARCINOMA

PURPOSE We report stage specific followup guidelines based on our evaluation of the pattern of recurrence in 286 patients treated for local N0 or Nx renal cell carcinoma. MATERIALS AND METHODS We retrospectively reviewed the clinical records of 286 patients with pT1 to pT3N0 or Nx renal cell carcinoma who underwent nephrectomy at our center between February 1985 and December 1994. In cases of later metastases the median interval to first metastasis, site of metastasis and method of diagnosis were correlated with the primary lesion stage. RESULTS Metastases developed in 68 patients a median of 23 months after nephrectomy. Eight of the 113 patients with pT1 disease had metastases (median time to diagnosis 38 months), while 17 of 64 with pT2 disease and 43 of 109 with pT3 disease had metastases (medians 32 and 17 months, respectively). Of the 92 metastases 59 (64%) were asymptomatic, including 44 detected on routine chest x-rays (32) and blood tests (12). Isolated asymptomatic intra-abdominal metastases were diagnosed by surveillance computerized tomography in only 6 patients (9%). The remaining patients with metastases had associated clinical symptoms and/or abnormal results on interval tests that prompted further diagnostic studies. CONCLUSIONS We confirmed that the risk of metastatic renal cell carcinoma is stage dependent. Therefore, surveillance protocols should be based on the pathological stage of the primary tumor. We recommend an annual chest x-ray, and serum liver function and alkaline phosphatase level tests for patients with pT1 disease. These studies are indicated beginning at 6 and 3 months for pT2 and pT3 disease, respectively, continuing every 6 months for 3 years and then annually. Surveillance computerized tomography should be performed at 24 and 60 months in patients with pT2 and pT3 disease or earlier when the results of any routine study are abnormal or clinical symptoms are present. Bone and brain surveillance studies should be prompted by site specific symptoms, elevated alkaline phosphatase levels or the diagnosis of metastasis at another site.

Integrated Therapy for Locally Advanced Bladder Cancer: Final Report of a Randomized Trial of Cystectomy Plus Adjuvant M-VAC Versus Cystectomy With Both Preoperative and Postoperative M-VAC

PURPOSE We conducted a phase III trial to investigate the timing of chemotherapy with respect to surgery for patients with resectable but high-risk urothelial cancer. The trial was also designed to evaluate the accuracy of clinical staging in patients with locally advanced cancer and the prognostic significance of chemotherapy-induced downstaging. PATIENTS AND METHODS A total of 140 uniformly evaluated patients with locally advanced urothelial cancer were studied. Planned treatment was five cycles of chemotherapy (M-VAC: methotrexate, vinblastine, doxorubicin, and cisplatin) plus radical cystectomy and pelvic lymph node dissection. Patients were randomly assigned to receive either two courses of neoadjuvant M-VAC followed by surgery plus three additional cycles of chemotherapy, or, alternatively, to have initial cystectomy followed by five cycles of adjuvant chemotherapy. RESULTS There were no significant differences in outcome between the two groups. By intent-to-treat, 81 patients (58%) remain disease-free, with median follow-up of 6.8 years. We confirmed a high rate of clinical understaging in this cohort, especially among patients showing lymphovascular invasion on biopsy. Patients with no residual muscle-invasive disease at cystectomy after neoadjuvant chemotherapy were likely to be cured. CONCLUSION These results lend further support to the impression from small randomized trials that, in a high-risk cohort, there is an improved cure fraction by the combination of multiagent chemotherapy and surgery, although we found no preferred sequence. Importantly, it is possible to select appropriate patients for such therapy on the basis of clinical staging information. These results establish a benchmark of outcome for this cohort.

Use of the University of California Los Angeles integrated staging system to predict survival in renal cell carcinoma: an international multicenter study.

PURPOSE To evaluate ability of the University of California Los Angeles Integrated Staging System (UISS) to stratify patients with localized and metastatic renal cell carcinoma (RCC) into risk groups in an international multicenter study. PATIENTS AND METHODS 4,202 patients from eight international academic centers were classified according to the UISS, which combines TNM stage, Fuhrman grade, and Eastern Cooperative Oncology Group performance status. Distribution of the UISS categories was assessed in the overall population and in each center. RESULTS The UISS stratified both localized and metastatic RCC into three different risk groups (P <.001). For localized RCC, the 5-year survival rates were 92%, 67%, and 44% for low-, intermediate-, and high-risk groups, respectively. A trend toward a higher risk of death was observed in all centers for increasing UISS risk category. For metastatic RCC, the 3-year survival rates were 37%, 23%, and 12% for low-, intermediate-, and high-risk groups, respectively; in 6 of 8 centers, a trend toward a higher risk of death was observed for increasing UISS risk category. A greater variability in survival rates among centers was observed for high-risk patients. CONCLUSION This study defines the general applicability of the UISS for predicting survival in patients with RCC. The UISS is an accurate predictor of survival for patients with localized RCC applicable to external databases. Although the UISS may be useful for patients with metastatic RCC, it may be less accurate in this subset of patients due to the heterogeneity of patients and treatments.

Surgical Management of Renal Cell Carcinoma With Inferior Vena Cava Tumor Thrombus

BACKGROUND The optimal management of patients with renal cell carcinoma with inferior vena cava tumor thrombus remains unresolved. Traditional approaches have included resection with or without the use of cardiopulmonary bypass. Chemotherapy has played a minor role except for biotherapeutic agents used for metastatic disease. METHODS From January 1989 to January 1996, 37 patients with renal cell carcinoma and inferior vena cava tumor thrombus underwent surgical resection. The 27 men and 10 women had a median age of 57 years (range, 29 to 78 years). Thirty-six patients presented with symptoms; 21 had hematuria. Distant metastases were present in 12 patients. Tumor thrombi extended to the infrahepatic inferior vena cava (n = 16), the intrahepatic inferior vena cava (n = 16), the suprahepatic inferior vena cava (n = 3), and into the right atrium (n = 2). All tumors were resected by inferior vena cava isolation and, when necessary, extended hepatic mobilization and Pringle maneuver, with primary or patch closure of the vena cavotomy. Cardiopulmonary bypass was necessary in only 2 patients with intraatrial thrombus. RESULTS Complications occurred in 11 patients, and 1 patient died 2 days postoperatively of a myocardial infarction (mortality, 2.7%). Twenty patients are alive; overall 2- and 5-year survival rates were 61.7% and 33.6%, respectively. For patients without lymph node or distant metastases (stage IIIa), 2- and 5-year survival rates were 74% and 45%, respectively. The presence of distant metastatic disease (stage IV) at the time of operation did not have a significant adverse effect on survival, as reflected by 2- and 5-year survival rates of 62.5% and 31.3%, respectively. Lymph node metastases (stage IIIc) adversely affected survival as there were no long-term survivors. CONCLUSIONS Resection of an intracaval tumor thrombus arising from renal cell carcinoma can be performed safely and can result in prolonged survival even in the presence of metastatic disease. In our experience, extracorporeal circulatory support was required only when the tumor thrombus extended into the heart.

The Efficacy and Complications of Salvage Cryotherapy of the Prostate

PURPOSE A phase I/II study was done to evaluate the efficacy and complications of salvage cryotherapy as a treatment for locally recurrent prostate cancer following full dose radiation therapy and/or systemic therapy. The efficacy of single and double freeze-thaw cycles was compared using posttreatment prostate specific antigen (PSA) levels and prostate biopsies as end points. MATERIALS AND METHODS A total of 150 patients with locally recurrent prostate cancer following radiation, hormonal therapy and/or systemic chemotherapy underwent salvage cryotherapy using a single (71 men, mean followup 17.3 months) or double (79 men, mean followup 10.0 months) freeze-thaw cycle. PSA was measured approximately every 3 months postoperatively and sextant biopsies were repeated 6 months postoperatively. Complications were assessed by retrospective chart review and a mailed quality of life survey. RESULTS Overall, 45 patients (31%) had persistently undetectable PSA. Patients with a history of radiation therapy only who underwent a double freeze-thaw cycle had a higher negative biopsy rate (93 versus 71%, p < 0.02) and lower biochemical failure rate (defined as an increase in serum PSA of 0.2 ng./ml. above the nadir value, 44 versus 65%, p < 0.03) than those who underwent a single freeze-thaw cycle. The main complications of salvage cryotherapy were urinary incontinence (73% of the patients), obstructive symptoms (67%), impotence (72%) and severe perineal pain (8%). CONCLUSIONS Salvage cryotherapy impacts local tumor control as evident by the high frequency of negative posttreatment biopsies. A double freeze-thaw cycle appears more effective than a single cycle. Like salvage prostatectomy, salvage cryotherapy causes significant morbidity.

Evaluation of Genetic Variants in MicroRNA-Related Genes and Risk of Bladder Cancer

MicroRNAs (miRNA) are small noncoding RNA molecules involved in a diversity of cellular functions. Although it has been reported that global suppression of the miRNA biogenesis pathway leads to enhanced tumorigenesis, the effect of common genetic variants of miRNA-related genes on cancer predisposition is unclear. To better understand this effect, we genotyped 41 single-nucleotide polymorphisms (SNP) from 24 miRNA-related genes in a case-control study conducted in 746 Caucasian patients with bladder cancer and 746 matched controls. The homozygous variant genotype of a nonsynonymous SNP in the GEMIN3 gene (rs197414) was associated with a significantly increased bladder cancer risk [odds ratios (OR), 2.40; 95% confidence interval (95% CI), 1.04-5.56]. Several additional miRNA-related SNPs were also identified that showed a borderline significant association with bladder cancer risk. Haplotype analysis indicated that a common haplotype of the GEMIN4 gene was associated with a significantly increased bladder cancer risk with an OR of 1.25 (95% CI, 1.01-1.54). To assess the aggregate effects of the promising SNPs, we performed a combined unfavorable genotype analysis that included all SNPs showing at least a borderline statistical significance. We found that, compared with the low-risk reference group with less than two unfavorable genotypes, the medium-risk group with two unfavorable genotypes exhibited a 1.29-fold (0.92-1.81) increased risk whereas the high-risk group with more than two unfavorable genotypes exhibited a 1.92-fold (1.36-2.71) increased risk (P(trend) < 0.0001). Overall, this is the first epidemiologic study showing that miRNA-related genetic variants may affect bladder cancer risk individually and jointly.

Genetic variation in the prostate stem cell antigen gene PSCA confers susceptibility to urinary bladder cancer

We conducted a genome-wide association study on 969 bladder cancer cases and 957 controls from Texas. For fast-track validation, we evaluated 60 SNPs in three additional US populations and validated the top SNP in nine European populations. A missense variant (rs2294008) in the PSCA gene showed consistent association with bladder cancer in US and European populations. Combining all subjects (6,667 cases, 39,590 controls), the overall P-value was 2.14 × 10−10 and the allelic odds ratio was 1.15 (95% confidence interval 1.10–1.20). rs2294008 alters the start codon and is predicted to cause truncation of nine amino acids from the N-terminal signal sequence of the primary PSCA translation product. In vitro reporter gene assay showed that the variant allele significantly reduced promoter activity. Resequencing of the PSCA genomic region showed that rs2294008 is the only common missense SNP in PSCA. Our data identify rs2294008 as a new bladder cancer susceptibility locus.

Role of epithelial-to-mesenchymal transition (EMT) in drug sensitivity and metastasis in bladder cancer

Epithelial-to-mesenchymal transition (EMT) is a process that plays essential roles in development and wound healing that is characterized by loss of homotypic adhesion and cell polarity and increased invasion and migration. At the molecular level, EMT is characterized by loss of E-cadherin and increased expression of several transcriptional repressors of E-cadherin expression (Zeb-1, Zeb-2, Twist, Snail, and Slug). Early work established that loss of E-cadherin and increased expression of MMP-9 was associated with a poor clinical outcome in patients with urothelial tumors, suggesting that EMT might also be associated with bladder cancer progression and metastasis. More recently, we have used global gene expression profiling to characterize the molecular heterogeneity in human urothelial cancer cell lines (n = 20) and primary patient tumors, and unsupervised clustering analyses revealed that the cells naturally segregate into two discrete “epithelial” and “mesenchymal” subsets, the latter consisting entirely of muscle-invasive tumors. Importantly, sensitivity to inhibitors of the epidermal growth factor receptor (EGFR) or type-3 fibroblast growth factor receptor (FGFR3) was confined to the “epithelial” subset, and sensitivity to EGFR inhibitors could be reestablished by micro-RNA-mediated molecular reversal of EMT. The results suggest that EMT coordinately regulates drug resistance and muscle invasion/metastasis in urothelial cancer and is a dominant feature of overall cancer biology.