Prominence of urinary biomarkers for bladder cancer in the COVID-19 era: From the commercially available to new prospective candidates

Epigenetic changes associated with Bacillus Calmette-Guerin (BCG) treatment in bladder cancer

Bacillus Calmette-Guérin (BCG) treatment for non-muscle invasive bladder cancer (NMIBC) is an established immunotherapeutic, however, a significant portion of patients do not respond to treatment. Despite extensive research into the therapeutic mechanism of BCG, gaps remain in our understanding. This review specifically focuses on the epigenomic contributions in the immune microenvironment, in the context of BCG treatment for NMIBC. We also summarise the current understanding of NMIBC epigenetic characteristics, and discuss how future targeted strategies for BCG therapy should incorporate both epigenomic biomarkers in conjunction with genomic biomarkers.

Serum EZH2 is a novel biomarker for bladder cancer diagnosis and prognosis

Objective

The primary objective of this study was to examine the levels of serum EZH2 in patients diagnosed with bladder cancer, and subsequently evaluate its potential as a biomarker for both the diagnosis and prognosis of bladder cancer.

Methods

Blood samples were obtained from 115 bladder cancer patients and 115 healthy persons. We measured the EZH2 concentrations in the serum of these subjects via enzyme-linked immunosorbent assay (ELISA). To assess the diagnostic performance of serum EZH2 in detecting bladder cancer, we plotted receiver operating characteristic (ROC) curves and calculated their corresponding area under the curve (AUC). We also used the Cox regression model and log-rank test to investigate the correlation between EZH2 levels and clinicopathological characteristics, and survival rates of bladder cancer patients.

Results

Serum EZH2 levels were significantly higher in bladder cancer patients when compared to those in healthy persons. Serum EZH2 levels exhibited a significant correlation with TNM stage, lymph node metastasis, muscle invasion, and tumor size. At a cutoff value of 8.23 ng/mL, EZH2 was able to differentiate bladder cancer patients from healthy persons, with an AUC of 0.87, a sensitivity of 81.31%, and a specificity of 78.42%. High EZH2 levels correlated with poor overall survival rates and progression-free survival rates of bladder cancer patients.

Conclusions

Serum EZH2 levels were elevated in bladder cancer patients, and patients with higher serum EZH2 levels exhibited a poorer prognosis. This indicates that serum EZH2 could be a novel biomarker for bladder cancer diagnosis and prognosis. Such findings could improve the prognosis of bladder cancer patients by facilitating early detection and continuous monitoring.

AHNAK2 Urinary Protein Expression as Potential Biomarker for Bladder Cancer Detection: A Pilot Study

OBJECTIVE

This study aimed to measure the AHNAK2 urinary levels in bladder cancer patients.

MATERIAL AND METHODS

This prospective case-control study enrolled 67 participants between January and March 2019 and were categorized into bladder cancer group (n=37), with histologically proven bladder can cer, and control group (n=30), with histologically verified benign lesions or with no bladder cancer indica tion during follow-up. Urine samples of 15 mL were collected in the mid-morning before cystoscopy/surger y and an enzyme-linked immunosorbent assay was performed as per the manufacturer's protocol. Bladder malignancies were classified according to the World Health Organization Tumor Classification. Group's associations were evaluated with the Student t-test, Spearman's rank correlation, and Mann-Whitney U test, while receiver operating curve was plotted for assessing the test's performance.

RESULTS

Mean age of the bladder cancer group was 66.41 years (standard deviation=10.04, range=43-82 years) and the control group was 59.67 years (standard deviation=10.44, range=38-77 years). All bladder cancers were of the urothelial histotype, with the following pT distribution: pTa/papillary urothelial neoplasm of low malignant potential (n=19; 28.4%), Primary tumor (pT) in situ (n=4; 6%), pT1 (n=7; 10.4%), and pT≥2 (n=7; 10.48%). Mean AHNAK2 levels were higher in bladder cancer patients 49.08 pg/mL (standard deviation=114.91) compared to controls 5.28 pg/mL (standard devia tion=6.65), P < .05). Significant differences were noted between non-invasive bladder cancer (n=23; mean=7.14 pg/mL; standard deviation=7.26) and invasive bladder cancer (n=14; mean=117.99 pg/mL; standard deviation=168.08) and between non-muscle invasive bladder cancer (mean=23.19 pg/mL; standard deviation=66.93) and muscle-invasive bladder cancer (mean=160.05 pg/mL; standard devia tion=199.65) (P < .001). The result of the assays was given as follows: sensitivity: 64.19%, specificity: 66.67%, positive predictive value: 22.07%, negative predictive value: 92.37%, area under curve: 0.695, and 95% CI: 0.57-0.82.

CONCLUSION

AHNAK2 protein could be used as bladder cancer surveillance biomarker. The inclusion of AHNAK2 levels in stratification nomograms might reduce the number of unnecessary cystoscopies.

Tapered catheter-based transurethral photoacoustic and ultrasonic endoscopy of the urinary system

Early diagnosis is critical for treating bladder cancer, as this cancer is very aggressive and lethal if detected too late. To address this important clinical issue, a photoacoustic tomography (PAT)-based transabdominal imaging approach was suggested in previous reports, in which its in vivo feasibility was also demonstrated based on a small animal model. However, successful translation of this approach to real clinical settings would be challenging because the human bladder is located at a depth that far exceeds the typical penetration depth of PAT (∼3 cm for in vivo cases). In this study, we developed a tapered catheter-based, transurethral photoacoustic and ultrasonic endoscopic probe with a 2.8 mm outer diameter to investigate whether the well-known benefits of PAT can be harnessed to resolve unmet urological issues, including early diagnosis of bladder cancer. To demonstrate the in vivo imaging capability of the proposed imaging probe, we performed a rabbit model-based urinary system imaging experiment and acquired a 3D microvasculature map distributed in the wall of the urinary system, which is a first in PAT, to the best of our knowledge. We believe that the results strongly support the use of this transurethral imaging approach as a feasible strategy for addressing urological diagnosis issues.