SPP1A and VEGFC splice isoforms as predictive diagnostic biomarkers for high and low-grade bladder cancer.

Objectives: This study aimed to investigate the expression of Vascular endothelial growth factor (VEGF) and Secreted phosphoprotein-1 (SPP1) isoforms in bladder cancer tissue and their correlation with tumor grade and muscle invasion.

Methods: In a prospective study, we examined 40 patients who had been diagnosed with bladder cancer. The diagnosis was confirmed through cystoscopy, biopsy, and histopathology. We used the RT-PCR method to measure the levels of human SPP1 and VEGF splice isoforms. Statistical analysis of the average of three replicates was performed using SPSS for Windows version 23.0.

Results: The study revealed a significant correlation between patients' histological grades and muscle invasiveness. Additionally, the investigation of 5 isoforms in patients showed that SPP1A, SPP1B, and VEGFA isoforms were significantly associated with tumor grade. However, the SPP1C and VEGFC isoforms showed no significant association with tumor grade. A new index was calculated based on the logistic regression model (mean_SPP1A - (mean_VEGFC * 0.7)), and the cut-off and the Area Under the ROC curve (AUC) were 23.1 and 0.951, respectively.

Conclusions: The relationship between the grade of bladder cancer and the two isoforms of SPP1A and VEGFC shows that these indicators could help pathologists differentiate between high and low-grade bladder cancer and potentially be used as predictive markers.