Evaluation of serum fibronectin levels and fibronectin gene polymorphism in patients receiving intravesical BCG therapy for non-muscle invasive bladder cancer and its prognostic value

Background: Bladder cancer continues to be a significant health issue, leading to ongoing research into novel biomarkers and treatment strategies. This study aims to evaluate the potential of serum fibronectin levels and fibronectin gene polymorphisms as biomarkers for predicting the recurrence and treatment response in patients with NMIBC undergoing intravesical BCG therapy.

Methods: Between June 2022 and December 2022, data of 73 patients who applied to the Mersin University Urology Clinic due to NMIBC and were followed and treated in our clinic, receiving intravesical BCG treatment, when necessary, as well as 56 individuals without any malignancy, were prospectively examined. Serum fibronectin levels were measured using the enzyme-linked immunosorbent assay method. PCR testing was applied for the fibronectin gene RS10202709 and RS 35,343,655 gene polymorphisms by using Real-Time PCR.

Results: The mean serum fibronectin level in the patient group was 76.794 ± 66.998ng/ml. Simultaneously, it was 50.486 ± 25.156ng/ml in the control group, and these differences in serum fibronectin levels were statistically significant(p = 0.003). Out of the 73 patients included in the study, recurrence of bladder cancer was observed in 53 of them. They were divided into two groups based on the recurrence times: early recurrence and late recurrence. The mean fibronectin level in the early recurrence group was 102 ± 86.1 ng/ml, while it was 44.7 ± 11.8 ng/ml in the late recurrence group. Emphasize the significance of the higher fibronectin levels in the early recurrence group by stating, patients with early recurrence exhibited significantly higher serum fibronectin levels compared to those with late recurrence (p < 0.001), suggesting a potential role for fibronectin as a prognostic biomarker.

Conclusions: The statistically higher concentrations of serum fibronectin levels in patients with bladder cancer observed in our study are a noteworthy finding. These findings suggest that serum fibronectin levels could serve as a valuable prognostic biomarker for early recurrence in NMIBC patients, although their predictive value for BCG treatment response remains limited.