Correlation between myc/bcl-2 co-expression and myc/p53 co-expression and prognosis of diffuse large B-cell lymphoma / 白血病·淋巴瘤

ABSTRACT

Objective To explore the relationship between myc/bcl-2 and myc/p53 co-expression and the prognosis of diffuse large B-cell lymphoma (DLBCL). Methods A total of 148 DLBCL cases with the follow-up data in Shanxi Cancer Hospital from January 2010 to October 2014 were selected. The expression of myc, bcl-2 and p53 protein in paraffin samples was detected by immunohistochemistry (IHC). Results The positive expression rate of myc, bcl-2 and p53 was 35.1 % (52/148), 60.1 % (89/148) and 24.3 % (36/148) respectively in 148 patients with DLBCL. There were 37 (25.0%) cases of myc/bcl-2 co-expression, which were correlated with Hans classification (χ2= 4.749, P= 0.029), IPI score (χ2= 4.894, P= 0.027), bone marrow invasion (χ2= 4.751, P= 0.029), and efficacy evaluation (χ2= 9.14, P= 0.003). Myc/p53 co-expression was detected in 17 cases (11.5 %), which was associated with Hans classification (χ2 = 5.349, P= 0.021) andLDH level (χ2= 11.1, P= 0.001). Univariate analysis revealed that myc [overall survival (OS) χ2= 6.044, P= 0.014; progression free survival (PFS)χ2= 6.212, P= 0.013], bcl-2 (OSχ2= 5.812, P= 0.016; PFSχ2= 4.878, P= 0.027), p53 (OSχ2= 20.092, P< 0.0001; PFSχ2= 18.492, P< 0.0001), myc/bcl-2 co-expression (OS χ2= 11.277, P= 0.001; PFSχ2= 9.024, P= 0.003) and myc/p53 co-expression (OS χ2=21.150, P< 0.0001; PFS χ2 = 18.655, P< 0.0001) were the adverse prognostic factors. In addition, the survival rate of the co-expression group was lower than that of single expression group, and the survival rate of myc/p53 co-expression group was lower than that of myc/bcl-2 co-expression group. Multivariate analysis showed that among the six independent variables, including myc, bcl-2, p53, myc/bcl-2, myc/p53 and treatment regimen, p53 expression was an independent prognostic affecting factor of OS (95%CI 0.172ˉ0.763, P=0.008) and PFS (95%CI 0.172ˉ0.773, P=0.009). Conclusion Myc, bcl-2 and p53 are the poor prognostic factors in DLBCL. Myc/bcl-2 and myc/p53 co-expression have synergistic effect, indicating the poor prognosis.