Développement d’une approche de protéomique quantitative pour la détection de nouveaux biomarqueurs urinaires spécifiques au cancer de la vessie

Bladder cancer represents a significant challenge for the healthcare system, as it is the 5th most common cancer in the Canadian population. Furthermore, bladder cancer is the 4th most common cancer in men and the 10th most common in women. The main symptom of bladder cancer is hematuria, but this is not specific to bladder cancer. Therefore, when a patient presents with hematuria, they are typically referred directly to a urologist, and the methods used for detection, diagnosis, and monitoring are cystoscopy and cytology. These methods have been used for decades, but they have several limitations and drawbacks, including their invasiveness for the patient, their limited diagnostic accuracy, and the high costs associated with the need for specialized equipment and a medical team. Moreover, many patients who present with hematuria do not have bladder tumors. Thus, it is essential to develop a new detection approach to better screen patients who require urological consultation. In this context, a preliminary study using mass spectrometry on the urinary proteome of urine samples collected during cystoscopy from patients with bladder cancer and patients without bladder tumors identified a combination of four biomarkers that correctly identified 100% of patients with high-grade bladder tumors when at least two biomarkers were positive. Therefore, the current research aimed to develop a new quantitative proteomics approach based on mass spectrometry using the PRM principle to detect new urinary biomarkers specific to bladder cancer, thus providing a new detection method that will be more accessible, painless, non invasive, and less expensive. The results of this study showed that the new approach is more sensitive than specific, meaning that it effectively identifies patients with bladder cancer, but also produces a high rate of false positives. However, it should be noted that the study cohort is not fully representative and includes twice as many control patients as patients with bladder cancer.