Pentraxin-3 is known to promote the transition of monocytes to fibrocytes, though little is known about its role in myelofibrosis.
Primary myelofibrosis (PMF), a rare myeloproliferative neoplasm, involves enlarged spleen, hematopoiesis occurring in organs outside of the bone marrow, and progressive bone marrow (BM) fibrosis. The level of BM fibrosis is known to correlate with poor survival.
Writing in a letter to The British Journal of Haematology, a research team explained that, in seeking to identify the mechanism of BM fibrosis, they identified large numbers of fibrocytes in the BM, as well as increased levels of the pentraxin C-reactive protein (CRP) in the plasma, of patients with PMF. Another pentraxin, pentraxin-3 (PTX3), is known to promote the transition of monocytes to fibrocytes, though little is known about PTX3’s role in PMF.
The team examined PTX3 plasma levels from 140 patients with PMD and compared them with 30 samples from healthy volunteers, and found that PTX3’s plasma levels were significantly higher in patients with PMF, as were CRP plasma levels. They also found that high CRP levels were associated with unfavorable overall survival (OS).
Using a multivariate Cox proportional hazard regression model, the researchers found that OS was independently predicted by both PTX3 (HR, 1.77, P = .03) and CRP (HR, 1.95, P = .019). Furthermore, high PTX3 and high CRP correlated with unfavorable prognostic indicators identified in the Dynamic International Prognostic Scoring System’s risk stratification.
Furthermore, PTX3 levels were also correlated with parameters of tumor burden, including total leucocyte count and spleen size, and with the severity of patients’ constitutional symptoms and performance status.
“Our data suggest that PTX3 plasma levels constitute an independent indicator of disease burden, clonal expansion and overall survival in patients with PMF,” concluded the authors. “Therefore, monitoring of PTX3 plasma levels might be a useful tool in clinical decision making.”
Veletic I, Manshouri T, Newberry KJ, Garnett J, Verstovsek S, Estrov Z. Pentraxin-3 plasma levels correlate with tumor burden and overall survival in patients with primary myelofibrosis. [Published online August 3, 2018.] Br J Haematol. doi: 10.1111/bjh.15528.