Macrophage inflammatory protein 1 alpha (MIP-1α) may be associated with poor outcome in patients with extranodal NK/T-cell lymphoma.

The macrophage inflammatory protein 1 (MIP-1) is anticipated to have a role in extranodal natural killer (NK)/T-cell lymphoma (ENKTL) because the expression of MIP-1 is related to Epstein-Barr virus (EBV) latency in EBV-related non-Hodgkin lymphoma cells. Thus, we measured the serum level of MIP-1 in 69 patients with ENKTL using frozen serum samples that were archived at diagnosis. As serum level of MIP-1 was not detectable in 19 patients (range: 0-24.37pg/mL), patients were dichotomized into positive (n=50) and negative (n=19) MIP-1 groups according to the presence of detectable level of MIP-1 in serum. MIP-1-positive group showed a significantly poor overall survival (OS) in comparison with the MIP-1-negative group (p=0.004). In the subgroup analysis, the positivity of MIP-1 was significantly associated with OS in patients with stage IIIE/IV and a detectable level of EBV DNA (p=0.002 and 0.032, respectively). Multivariate analysis also showed that the positivity of MIP-1 was independently associated with worse OS together with bone marrow involvement (p=0.002). An in vitro study with patient-derived ENKTL tumour cells showed the expression of CCR1 and CCR5 on the surface of tumour cells (28% and 14%, respectively) , and the addition of MIP-1 to the culture media of tumour cells increased cell growth supporting the negative impact of MIP-1 on the prognosis of ENKTL patients. In conclusion, serum levels of MIP-1 could predict survival outcomes in patients with ENKTL. Therefore, MIP-1 should be considered for prognostication and a potential therapeutic target. Copyright (c) 2016 John Wiley & Sons, Ltd.