Diagnostic Potential of Circulating Tumor Cells, Urinary MicroRNA, and Urinary Cell-Free DNA for Bladder Cancer: A Review

Early detection of primary bladder cancer (BCa) is vital, because stage and grade have been generally accepted not only as categorical but also as prognostic factors in patients with BCa. The widely accepted screening methods for BCa, cystoscopy and urine cytology, have unsatisfactory diagnostic accuracy, with high rates of false negatives, especially for flat-type BCa with cystoscopy and for low-risk disease with urine cytology. Currently, liquid biopsy has attracted much attention as being compensatory for that limited diagnostic power. In this review, we survey the literature on liquid biopsy for the detection of BCa, focusing on circulating tumor cells (CTCs), urinary cell-free DNA (ucfDNA), and urinary microRNA (umiRNA). In diagnostic terms, CTCs and umiRNA are determined by quantitative analysis, and ucfDNA relies on finding genetic and epigenetic changes. The ideal biomarkers should be highly sensitive in detecting BCa. Currently, CTCs produce an unfavorable result; however, umiRNA and ucfDNA, especially when analyzed using a panel of genes, produce promising results. However, given the small cohort size in most studies, no conclusions can yet be drawn about liquid biopsy's immediate application to clinical practice. Further large studies to validate the diagnostic value of liquid biopsy for clinical use are mandatory.

Blood-based protein biomarkers in bladder urothelial tumors

Bladder cancer (BC) is the fifth most common cancer with a high prevalence rate. It is classically classified in two groups, namely non-muscle invasive (NMIBC) and muscle invasive (MIBC). NMIBC accounts for 75% of cases and has a better prognosis than MIBC. However, 30-50% of the NMIBC patients will show recurrences throughout their lives, and about 10-20% of them will progress to MIBC, with frequent metastasis and a reduced survival rate. The diagnosis of bladder cancer is confirmed by direct visualization of the tumour and other mucosal abnormalities with endoscopic excision using cystoscopy and transurethral resection of the bladder (TURBT). An adequate TURBT requires complete resection of all visible tumour with appropriate sampling of the bladder to assess the depth of invasion. However, for many years, researchers have attempted to identify and utilise urinary markers for bladder cancer detection. Voided urine cytology has been the mainstay of urine-based diagnosis of bladder cancer since originally described by Papanicolau and Marshall. Nonetheless, urine cytology has several drawbacks, including a poor sensitivity for low-grade/stage tumours, a lack of interobserver consistency and a variable range of readings (e.g., atypical, atypical-suspicious, non-diagnostic). These shortcomings have inspired the search for more sensitive bladder cancer biomarkers. To bring precision medicine to genitourinary oncology, the analysis of the plasma/serum wide genome and proteome offers promising possibilities.

The attributes of plakins in cancer and disease: perspectives on ovarian cancer progression, chemoresistance and recurrence

The plakin family of cytoskeletal proteins play an important role in cancer progression yet are under-studied in cancer, especially ovarian cancer. These large cytoskeletal proteins have primary roles in the maintenance of cytoskeletal integrity but are also associated with scaffolds of intermediate filaments and hemidesmosomal adhesion complexes mediating signalling pathways that regulate cellular growth, migration, invasion and differentiation as well as stress response. Abnormalities of plakins, and the closely related spectraplakins, result in diseases of the skin, striated muscle and nervous tissue. Their prevalence in epithelial cells suggests that plakins may play a role in epithelial ovarian cancer progression and recurrence. In this review article, we explore the roles of plakins, particularly plectin, periplakin and envoplakin in disease-states and cancers with emphasis on ovarian cancer. We discuss the potential role the plakin family of proteins play in regulating cancer cell growth, survival, migration, invasion and drug resistance. We highlight potential relationships between plakins, epithelial-mesenchymal transition (EMT) and cancer stem cells (CSCs) and discuss how interaction of these processes may affect ovarian cancer progression, chemoresistance and ultimately recurrence. We propose that molecular changes in the expression of plakins leads to the transition of benign ovarian tumours to carcinomas, as well as floating cellular aggregates (commonly known as spheroids) in the ascites microenvironment, which may contribute to the sustenance and progression of the disease. In this review, attempts have been made to understand the crucial changes in plakin expression in relation to progression and recurrence of ovarian cancer.

TROY expression is associated with pathological stage and poor prognosis in patients treated with radical cystectomy

BACKGROUND

New biomarkers may help us provide individualized prognosis and allow risk-stratified clinical decision making about radical treatment.

OBJECTIVES

This study aimed to determine the tumor necrosis factor of receptor superfamily 19 (TROY) expression in urothelial carcinoma and its relationship to clinicopathological findings.

METHODS

Immunohistochemical staining for TROY was carried out in 136 archival radical cystectomy specimens with immunoreactivity being stratified on a 0-9 scale. Expression scores for TROY were further stratified into negative (score 0) and positive (score 1 or greater). Median age was 65 years, and the median follow-up period was 50.7 months.

RESULTS

Expression of TROY was significantly associated with the pathological stage (p= 0.019) and expression of nestin (p= 0.013). Log-rank tests indicated that expression of TROY was significantly associated with disease progression and cancer-specific mortality (p= 0.044 and 0.008, respectively). In multivariate Cox regression analysis, lymph node status was the only independent prognostic factor for disease progression and cancer-specific survival. Expression of TROY was a marginal prognostic factor for cancer-specific survival.

CONCLUSIONS

TROY may therefore be a new molecular marker to aid in identifying and selecting patients undergoing radical cystectomy who could potentially benefit from multimodal treatment.

An epigenome-wide association analysis of cardiac autonomic responses among a population of welders

DNA methylation is one of the potential epigenetic mechanisms associated with various adverse cardiovascular effects; however, its association with cardiac autonomic dysfunction, in particular, is unknown. In the current study, we aimed to identify epigenetic variants associated with alterations in cardiac autonomic responses. Cardiac autonomic responses were measured with two novel markers: acceleration capacity (AC) and deceleration capacity (DC). We examined DNA methylation levels at more than 472,506 CpG probes through the Illumina Infinium HumanMethylation450 BeadChip assay. We conducted separate linear mixed models to examine associations of DNA methylation levels at each CpG with AC and DC. One CpG (cg26829071) located in the GPR133 gene was negatively associated with DC values after multiple testing corrections through false discovery rate. Our study suggests the potential functional importance of methylation in cardiac autonomic responses. Findings from the current study need to be replicated in future studies in a larger population.

Laparoscopic Retroperitoneal Nephroureterectomy is a Safe and Adherent Modality for Obese Patients with Upper Urinary Tract Urothelial Carcinoma

OBJECTIVE

We evaluated the association of body mass index (BMI) with perioperative outcomes in patients who underwent laparoscopic or open radical nephroureterectomy.

MATERIALS AND METHODS

This retrospective single-center study included 113 patients who had been diagnosed with upper urinary tract cancer from January 1998 to June 2013 and were treated with laparoscopic nephroureterectomy (Lap group, n=60) or open nephroureterectomy (Open group, n=53). Laparoscopic nephroureterectomy was performed via a retroperitoneal approach following an open partial cystectomy. The two surgical groups were stratified into a normal-BMI group (<25) and a high-BMI group (BMI≥25). The high-BMI group included 27 patients: 13 in the Lap group and 14 in the Open group.

RESULTS

Estimated blood loss (EBL) in the Lap group was much lower than that in the Open group irrespective of BMI (p<0.01). Operative time was significantly prolonged in normal-BMI patients in the Lap group compared to those in the Open group (p=0.03), but there was no difference in operative time between the Open and Lap groups among the high-BMI patients. Multivariate logistic regression analysis of the data for all the cohorts revealed that the open procedure was a significant risk factor for high EBL (p<0.0001, hazard ratio 8.02). Normal BMI was an independent predictor for low EBL (p=0.01, hazard ratio 0.25). There was no significant risk factor for operative time in multivariate analysis. There were no differences in blood transfusion rates or adverse event rates between the two surgical groups.

CONCLUSIONS

Laparoscopic radical nephroureterectomy via a retroperitoneal approach can be safely performed with significantly reduced EBL even in obese patients with upper urinary tract cancer.