| dc.description.abstract | Bladder cancer (BC) carries a large societal burden, in 2018 it was the 10th most common malignancy worldwide with 550,000 new cases and an estimated death rate of 200,000 (1). Patients diagnosed with low-grade tumors are difficult to identify and have a high recurrence rate. This commits the patients to extensive follow-up regimes using invasive methods such as cystoscopy which creates great discomfort for the patients, as well as high expenses for society (2). This shows the need for new noninvasive biomarkers for BC. In this thesis the potential BC biomarkers urinary microRNA and alterations urinary microbiome were analyzed in 26 patients’ samples, 16 benign and 10 malignant BC samples. Sequencing of human DNA was also performed to map gene alternations related to BC. An innovative Trilobite filter was used to fractionate the urine to enable easier urine analysis. It was also investigated if these filters could be reused. The filter setup was however not optimized by the supplier which resulted in analyzing most of the urine samples without filtration. A positive trend was observed in regards of reusing the filters, but this needs to be further investigated with an optimized filter setup. The results from the urine analysis showed that there was a significant presence of bacterial DNA in both benign and malignant urine samples, but unfortunately the DNA was not sequenced. In the qPCR analysis of microRNA (miRNA), the miRNA hsa-miR-23a-3p was upregulated in both malignant and benign samples compared to the reference miRNA hsa-miR-16-5p but was slightly more upregulated in benign samples. Since hsa-miR-23a-3p was easily detected in the samples which is positive for a biomarker, further investigation of differences in expression levels between malignant and benign samples could be of interest. Hsa-miR-96-5p and hsa-miR-155-5p were significantly upregulated in the malignant samples compared to benign samples, indicating that these two miRNAs could be potential biomarkers for malignancy. Furthermore, mutations in the FGFR3, PIK3CA, ERBB2 and ERBB3 genes were detected in the malignant BC urine samples. Mutations in the PDGFRA, MAP2K1 and SOM were detected in the benign BC urine samples. The study shows that there is potential for urinary miRNAs and gene alterations to be used as biomarkers for BC, but larger sample cohorts with the same number of malignant and benign samples is needed to validate the findings. Also, the bacterial DNA should be sequenced to see if there are significant differences in malignant and benign samples at genus or species level and if alterations in urinary microbiome could be used as a biomarker for BC. A statistical analysis should be performed to investigate whether combining the different datasets can lead to better identification of BC patients compared to using individual datasets alone. | |