Higher Viral Load of BK Polyomavirus in Urothelial Bladder Tumors Compared with Nontumoral Bladder Tissues

Abstract

Aim: This study examined BK polyomavirus (BKPyV) genome and viral load in urothelial bladder carcinoma (UBC) and nontumoral bladder tissues. Materials & methods: Quantitative real-time PCR was used to measure viral LT-Ag copy number per cell in 114 fresh-frozen bladder biopsy samples (61 UBC and 53 nontumoral tissue samples). Results: Patients with UBC had a significantly higher mean BKPyV LT-Ag DNA load than those without UBC. In multivariate logistic regression analysis, BKPyV LT-Ag copies/cell and smoking/illicit use of drugs were associated with bladder cancer. Receiver operating characteristic curve analysis identified bladder cancer risk at 0.1 copies/cell. Conclusion: This study found high BKPyV LT-Ag DNA copy numbers in most UBC samples, supporting the hypothesis that BKPyV induces UBC tumorigenesis.

Tweetable abstract

BK polyomavirus viral load in urothelial bladder carcinoma and non-UBC tissues were assessed. Normalized viral load of 114 fresh-frozen samples were determined using quantitative real-time PCR. Patients with urothelial bladder carcinoma had a higher viral load.

Keywords::

• BK polyomavirus
• human polyomavirus
• large tumor antigen
• urothelial bladder cancer
• viral load

Author contributions

F Sadeghi and E Moudi: developed the study concept, experimental protocols and were responsible for drafting and revising the manuscript. H Kamalinia and T Mostaghimi: wrote the manuscript and helped in the laboratory tests. M Taheri and M Shirzad: reviewing the manuscript and helped in the laboratory tests. AA Pasha and Y Yahyapour: carried out administrative and technical support.

Acknowledgments

The authors gratefully acknowledge A Bijani and H Gholinia for their technical support and valuable suggestions for this manuscript. The authors are also grateful to S Kamali for her help in sample collection.

Financial & competing interests disclosure

This work was funded and supported by Babol University of Medical Sciences (project code: 9809315). The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

No writing assistance was utilized in the production of this manuscript.

Ethical conduct of research

This research was approved by the local ethics committee with the ethical number: IR.MUBABOL.REC.1399.081 in Babol University of Medical Sciences, Babol, Iran, and written informed consent was collected from each patient. The authors state that they have obtained appropriate institutional review board approval or have followed the principles outlined in the Declaration of Helsinki for all human or animal experimental investigations. In addition, for investigations involving human subjects.

Additional information

Funding

This work was funded and supported by Babol University of Medical Sciences (project code: 9809315). The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed. No writing assistance was utilized in the production of this manuscript.