A-Mei Huang

The incidence of upper tract urothelial carcinoma (UTUC) in Taiwan is high, characterized by aggressive clinical behavior and a tendency to be more invasive at diagnosis. Identifying tumorigenic genes remains an important challenge. Myc binding protein 2 (MYCBP2) regulates the cAMP, p38MAPK, TSC/mTOR, and autophagy signaling pathways in mammalian cells. MYCBP2 dysfunction has been associated with poor prognosis in leukemia, melanoma, colon, and prostate cancer. Its role in UTUC needs to be clarified. We investigated the expression of MYCBP2 in UTUC and its relationship to patient outcomes. MYCBP2 expression levels were assessed by immunohistochemistry in 110 tissue samples from UTUC patients. Higher MYCBP2 protein expression was significantly correlated with worse disease‐free survival ( p = 0.001) and cancer‐specific survival ( p = 0.007). The major clinicopathological characteristics associated with MYCBP2 expression were stage, lymphovascular invasion, distant metastasis, recurrence, and cancer death. Based on multivariate analysis, pathological stage (HR:2.31, p = 0.017) and MYCBP2 expression (HR:2.75, p = 0.015) were significant predictors of disease‐free survival in UTUC. MYCBP2 is elevated in UTUC cell lines compared with immortalized uroepithelial cells. Knocking down MYCBP2 significantly suppressed cellular migration and invasion activity in BFTC909 cells. In conclusion, MYCBP2 expression might predict poor survival among UTUC patients.

Neurotrophic receptor tyrosine kinase 3 (NTRK3) has pleiotropic functions: it acts not only as an oncogene in breast and gastric cancers but also as a dependence receptor in tumor suppressor genes in colon cancer and neuroblastomas. However, the role of NTRK3 in upper tract urothelial carcinoma (UTUC) is not well documented. This study investigated the association between NTRK3 expression and outcomes in UTUC patients and validated the results in tests on UTUC cell lines. A total of 118 UTUC cancer tissue samples were examined to evaluate the expression of NTRK3. Survival curves were generated using Kaplan-Meier estimates, and Cox regression models were used for investigating survival outcomes. Higher NTRK3 expression was correlated with worse progression-free survival, cancer-specific survival, and overall survival. Moreover, the results of an Ingenuity Pathway Analysis suggested that NTRK3 may interact with the PI3K-AKT-mTOR signaling pathway to promote cancer. NTRK3 downregulation in BFTC909 cells through shRNA reduced cellular migration, invasion, and activity in the AKT-mTOR pathway. Furthermore, the overexpression of NTRK3 in UM-UC-14 cells promoted AKT-mTOR pathway activity, cellular migration, and cell invasion. From these observations, we concluded that NTRK3 may contribute to aggressive behaviors in UTUC by facilitating cell migration and invasion through its interaction with the AKT-mTOR pathway and the expression of NTRK3 is a potential predictor of clinical outcomes in cases of UTUC.

Kidney transplantation is a lifesaving option for patients with end-stage kidney disease. In Taiwan, urothelial carcinoma (UC) is the most common de novo cancer after kidney transplantation (KT). UC has a greater degree of molecular heterogeneity than do other solid tumors. Few studies have explored genomic alterations in UC after KT. We performed whole-exome sequencing to compare the genetic alterations in UC developed after kidney transplantation (UCKT) and in UC in patients on hemodialysis (UCHD). After mapping and variant calling, 18,733 and 11,093 variants were identified in patients with UCKT and UCHD, respectively. We excluded known single-nucleotide polymorphisms (SNPs) and retained genes that were annotated in the Catalogue of Somatic Mutations in Cancer (COSMIC), in the Integrative Onco Genomic cancer mutations browser (IntOGen), and in the Cancer Genome Atlas (TCGA) database of genes associated with bladder cancer. A total of 14 UCKT-specific genes with SNPs identified in more than two patients were included in further analyses. The single-base substitution (SBS) profile and signatures showed a relative high T > A pattern compared to COMSIC UC mutations. Ingenuity pathway analysis was used to explore the connections among these genes.GNAQ,IKZF1, andNTRK3were identified as potentially involved in the signaling network of UCKT. The genetic analysis of posttransplant malignancies may elucidate a fundamental aspect of the molecular pathogenesis of UCKT.

Background: Kidney transplantation is a lifesaving option of selected patients with end-stage kidney disease (ESKD). Urothelial carcinoma (UC) is the most common de novo cancer after kidney transplantation in Taiwan. UC has the characteristics of high mutational burden and elevated degree of molecular heterogeneity compared with other solid tumors. However, there are limited research exploring the genomic alterations in UC after kidney transplantation. Methods: In this study, we performed whole exome sequencing (WES) to compare the genetic alterations between UC developed after kidney transplantation (UCKT) and UC from hemodialysis patients (UCHD). After mapping and variant calling, a total of 18,733 and 11,093 mutations were identified from UCKT and UCHD patients, respectively. We first excluded known SNPs and then retained genes that were annotated in Cosmic, Intogen, and TCGA bladder databases for onco-driver genes. Seventeen UCKT unique genes with recurrent SNPs in more than two patients were subjected for further analysis. IPA pathway analysis was used to explore the interconnections among these genes. Results: 17 novel mutations of BTK, CARD11, ELL, FNBP1, GNAQ, HOXD13, IKZF1, MAX, MLLT10, NTRK3, PAX5, SEPTIN6, SEPTIN9, SH3GL1, SLC34A2, TAL1 , and TRAF7 were identified UCKT groups, and none of the genes had been reported in the genomes of patients with UC. Among the affected genes, GNAQ, IKZF1, and NTRK3 were potentially involved in the signaling network of UCKT. Conclusion : Our findings provide information for understanding the mutational landscape of UC developed after kidney transplantation, and a gene list that may be of great importance in related molecular mechanisms. Genetic analysis in malignancy after transplantation may help to identify high risk patients in post-transplant care and also illuminate a fundamental aspect of the molecular pathogenesis of post-transplantation UC.

Background: Ubiquitin-mediated protein degradation has been reported to be involved in regulating the activity of oncoproteins and tumor suppressors. Dysfunction or dysregulation of the ubiquitin-proteasome system may induce tumorigenesis. Deubiquitinase ubiquitin-specific protease 2a (USP2a) has been reported to regulate cell growth or death and is involved in the pathogenesis of various diseases, including cancers. However, the role of USP2a in upper tract urothelial carcinoma (UTUC) has not been investigated yet. The goal of this study was to evaluate the clinical significance of USP2a expression in UTUC. Materials and Methods: A total of 110 UTUC cases were included in this study. USP2a expression level was evaluated through immunohistochemistry staining, and the correlation of USP2a expression level with both clinical and pathologic variables was analyzed. Results: High USP2a expression level was observed in 48 (43.6%) cancer specimens. USP2a expression level was significantly correlated with tumor stage (P=0.001), grade (P=0.033), and tumor recurrence (P=0.008). High USP2a expression level was correlated with poor disease-free survival (P=0.005) and cancer-specific survival (P=2.31; P=0.007) and cancer-specific survival (hazard ratio=5.49; P=0.009). Conclusions: This study indicated that USP2a protein expression level may be a potential biomarker for predicting UTUC patient survival. Further prospective studies are needed to investigate the role of USP2a in UTUC progression.

Little is known regarding the molecular characterization of upper tract urothelial carcinoma (UTUC). Novel therapeutic targets and prognostic predictors are imminent. In the present study, we aim to examine the oncogenic function and molecular mechanism of Derlin-1 in UTUC. Derlin-1 overexpression is significantly associated with poor prognosis in patients with UTUC. In vitro, knockdown or over-expression of Derlin-1 markedly regulated UTUC cell invasion and migration. We further discovered miR-375-3p suppresses cell invasion and migration by inversely regulating Derlin-1 and blocking EMT in UTUC cells. Taking this together, miR-375-3p functions as a tumor suppressive microRNA by directly targeting Derlin-1 and blocking epithelial–mesenchymal transition (EMT) in UTUC.

This study aimed to examine the prognostic significance of preoperative inflammation-associated blood cell markers in the metachronous contralateral recurrence of upper tract urothelial carcinoma (UTUC). Patients with nonmetastatic UTUC treated in Taiwan and the U.S. between 1990 and 2017 were included. The Kaplan–Meier method was used to calculate the contralateral recurrence rate, and multivariate logistic regression was performed to study the association of blood cell markers and clinicopathological characteristics with contralateral recurrence. Overall, a total of 1039 patients were included in this study, 52 of whom (5.0%) developed metachronous recurrence of the contralateral side. Kaplan–Meier analysis indicated that a history of bladder cancer (p = 0.006), multiple tumors (p = 0.016), advanced chronic kidney disease (CKD; p < 0.001), elevated serum white blood cell (WBC) count (p < 0.001), and decreased hemoglobin levels (p = 0.001) significantly reduced the contralateral recurrence-free survival. Multivariate analysis showed that multiple tumors (hazard ratio (HR), 1.87; p = 0.030), advanced CKD (HR, 2.63; p = 0.002) and increased WBC count (HR, 2.60; p = 0.001) were independent risk factors for higher contralateral recurrence rate. Notably, advanced CKD was a significant factor regardless of the patient’s region. In summary, multiple tumors, advanced CKD and elevated serum WBC count are independent predictors of contralateral recurrence in patients with UTUC. It is recommended that patients with these adverse characteristics be closely followed up to monitor the opposite upper urinary tract.

Transcription factor CCAAT/enhancer‐binding protein delta (CEBPD) plays multiple roles in tumor progression. Studies have demonstrated that cisplatin (CDDP) induced CEBPD expression and had led to chemotherapeutic drug resistance. However, the underlying molecular mechanisms of CDDP‐regulated CEBPD expression and its relevant roles in CDDP responses remain elusive. MicroRNAs (miRNAs) are small non‐coding RNAs that negatively regulate gene expression in a sequence‐specific manner. Abnormal miRNAs expression is associated with tumor progression. In current study, a large‐scale PCR‐based miRNA screening was performed to identify CEBPD‐associated miRNAs in urothelial carcinoma cell line NTUB1. Eleven miRNAs were selected with more than twofold changes. MiR‐193b‐3p, a known tumor suppressor, down‐regulated proto‐oncogenes Cyclin D1, and ETS1 expression and led to cell cycle arrest, cell invasion, and migration inhibition. The expression of miR‐193b‐3p was associated with the DNA binding ability of CEBPD in CDDP response. CEBPD knocking‐down approach provided a strong evidence of the positive correlation between CEBPD and miR‐193b‐3p. CDDP‐induced CEBPD trans‐activated miR‐193b‐3p expression and it directly targeted the 3′‐UTR of Cyclin D1 and ETS1 mRNA, and silenced the protein expression. In addition, miR‐193b‐3p also inhibited cell migration activity, arrested cell at G1 phase, and sensitized NTUB1 to CDDP treatment. In conclusion, this study indicates that CEBPD exhibits an anti‐tumorigenic function through transcriptionally activating miR‐193b‐3p expression upon CDDP treatment. This study provides a new direction for managing human urothelial carcinoma. J. Cell. Biochem. 118: 1563–1573, 2017.