Peripheral and bone marrow CD34+ cell levels on chronic myeloproliferative disease

Pax3 inhibits Neuro-2a cells proliferation and neurite outgrowth

Pax3 and Pax7 are closely related transcription factors that are widely expressed in the developing nervous system and somites. During the normal development in the central nervous system (CNS), Pax3 and Pax7 are mainly expressed in the dorsal part of the neural tube. Further analysis revealed that Pax3 and Pax7 shared redundant functions in the spinal cord development. However, it is still unknown whether Pax3 and Pax7 play a role in neuronal differentiation. In this study, Pax3 and Pax7 genes were overexpressed in Neuro‐2a, the mouse neuroblastoma cell line. CCK‐8 and EdU assay results showed that overexpression of Pax3 inhibited cell viability and proliferation of Neuro‐2a cells, whereas the overexpression of Pax7 had no significant difference on their cell viability and proliferation. Overexpression of Pax3 not only increased the percentage of cells in the S phase and G0/G1 phase, but also decreased that in the G2 phase. Moreover, the total neurite lengths of Neuro‐2a cells were significantly shorter in Pax3 overexpressed group than those in negative control group and showed no significant difference between Pax7 overexpressed group and negative control group. These results suggested that Pax3 not only inhibited the cell viability and proliferation but also affected the cell cycle and the neurite outgrowth of Neuro‐2a cells. RNA sequencing analysis showed up‐regulated genes in Pax3 overexpressed group were involved in cell cycle machinery, which may reveal the potential mechanism of Neuro‐2a cells proliferation.

Association of mast cells and bone marrow reticulin fibrosis in patients with bcr-abl negative chronic myeloproliferative neoplasms

BACKGROUND

We aimed to investigate the association of bone marrow mast cell numbers (MCN) and the degree of reticulin fibrosis in patients with chronic myeloproliferative neoplasms (MPN).

METHODS

This was a case-control study that recruited 47 patients who were diagnosed with bcr-abl negative MPN. Thirty patients with lymphoma served as controls. JAK2 mutation was studied and all subjects underwent bone marrow biopsy at the time of diagnosis. Mast and CD34+ cells were counted. Marrow reticulin fiber was graded.

RESULTS

Thirty-four patients had essential thrombocythemia (ET), 8 patients had primary myelofibrosis (PMF) and 5 patients had polycythemia vera (PV). Fourteen MPN patients had JAK2, whereas the controls had not. MCN was higher in patients than controls (p = 0.001). There was no significant difference regarding CD34. Reticulin fibrosis was present in 57.4% of MPN patients, whereas there was any in controls. PMF patients had more CD34 + cells than PV and ET. PMF patients had more reticulin fibers compared with other subgroups (p < 0.001). MCN, but not CD34+ cell counts, was significantly higher in JAK2(+) patients than JAK2(-) patients.

CONCLUSION

MCN and reticulin fibrosis were significantly increased in MPN patients. JAK2 positivity had significantly increased MCN compared to patients without JAK2. JAK2 was associated with increased reticulin fibrosis.