Relation of beclin-1 and bcl-2 expressions with pathological parameters and prognosis in clear cell renal cell carcinomas

Abstract

Introduction: The most common type of renal cancers is the clear cell renal cell carcinoma (CCRCC) and 98% of CCRCCs have a loss of sequence in the short arm of chromosome 3 by deletion or translocation. Programmed cell death; another possible mechanism of tumorigenesis, comprises two separate components: apoptosis and autophagy. This study aims to show the relation between the prognostic parameters and survival, and Beclin-1, as the representative marker of autophagy, and Bcl-2 as the representative marker of apoptosis in CCRCC patients. In this study, we aimed to determine if Beclin-1 and Bcl-2 expression levels can provide any prognostic information about CCRCC patients. Methods: We examined a total of 84 patients who underwent partial or radical nephrectomy and were diagnosed as having CCRCC between January 2008 and December 2015. Immunohistochemical staining was performed, the evaluation was for Beclin-1 and Bcl-2 semi-quantitative, and based on the percentage of positively stained cells (proportion) and staining intensity. Results: There was only a statistical significance between Beclin-1 expression and age (r:-0.274; p=0.012; p <0.05). There was a marginal significance between ISUP grade and Beclin-1 (p=0.051). The relation of Bcl-2 expression with the ISUP grade, recurrence, metastasis, and mortality revealed statistical significance (p=0.001, p=0.019, p=0.009, p=0.013, respectively). The ISUP grade and the Bcl-2 expression revealed statistical significance on multivariate analysis ( HR 7.453, 95% CI: 1.935-28.713, p=0.004). The 5-year and 10-year tumor recurrences rates were lower in Bcl-2 positive group, and Bcl-2 positive group experienced longer disease free and overall survival. Conclusion: There was only marginal correlation between Beclin-1 expression and ISUP grade. No other histopathologic prognostic parameters histologic parameters revealed any signigificance. The higher expression of Bcl-2 is correlated with nuclear lower ISUP grade, lower pT stage, and longer disease free and overall survival.