PKM2 Expression Is Associated with Favorable Outcome in Patients with Diffuse Large B-Cell Lymphoma

Pyruvate kinase muscle isoenzyme 2 (PKM2) is a key enzyme in aerobic glycolysis and thought to contribute to cancer cell metabolic reprogramming. The aim of this study was to evaluate whether PKM2 expression by immunohistochemical was a potential prognostic biomarker in diffuse large B-cell lymphoma (DLBCL) patients. Herein, we explore the expression of PKM2 by immunohistochemistry in all 87 patients diagnosed as de novo DLBCL according to WHO classification. Among all the 87 patients, high expression of PKM2 was observed in 20 cases (23.0%). There was no significant difference in gender, age, B symptoms, performance status, LDH, stage and IPI score between patients with high and low PKM2 expression(P>0.05). Patients with high PKM2 expression showed significant superiorevent-free survival, but only a tendency in overall survival compared with low PKM2 expression patients (p=0.047 and p=0.465, respectively). Multivariate analysis showed that high expression of PKM2, independent of the international prognostic index, implied a favorable event-free survival (HR=0.363; 95% CI=0.109-0.927, p=0.038), but not overall survival (HR=0.646; 95% CI= 0.185-2.254, p=0.493). In conclusion, these data suggest that the expression of PKM2 may implied a good outcome in DLBCL patients treated with R-CHOP.