WWOX Mutations and Expression Pattern in Myeloproliferative Neoplasms رسالة ماجستير

Abstract

Myeloproliferative neoplasms (MPNs) are disorders associated with the uncontrolled proliferation of at least one of the hematopoietic cell lineages. MPNs are classified into Philadelphia chromosome-positive (Ph+) and Philadelphia chromosome-negative (Ph-), where the latter lacks defining genetic alterations. Mutations in JAK2, MPL, and CALR are associated with Ph-ve MPNs. However, all these mutations are involved in the diagnosis of a wide array of Philadelphia chromosome-negative MPNs, regardless of whether their symptomatic manifestations are quite different. WWOX is a known regulator of apoptosis, tumor suppression, and transcription factors. Alterations in WWOX expression were reported in polycythemia vera, primary myelofibrosis, and many types of cancers. This project used; PCR to investigate the deletions in WWOX exons, sanger sequencing to identify single nucleotide polymorphisms, and realtime PCR and western blot to study the alterations in mRNA and protein levels in either cases carrying ph-ve MPNs and/or blood-derived cell lines, respectively. No macro deletions in the sequence of WWOX exons were observed. However, five variants; rs11545029, rs7201683, rs3764340, rs73572838, and rs76204496, were detected. WWOX mRNA levels of patient samples and the cell lines; NB4, HL60, HEL1, SET2, and KG1, were significantly reduced. This was also observed at the protein levels in all the hematopoietic cell lines. This marks the first study on WWOX expression in patients with Philadelphia chromosomenegative MPNs in the region. The reduction in WWOX expression might be a potential lead to a new marker in the diagnosis and pathogenesis of Philadelphia chromosome-negative MPNs. The mRNA levels in the cell lines; NB4, HL60, VI HEL1, SET2, and KG1, were significantly reduced, which was also observed at the protein levels in all the hematopoietic cell lines. This marks the first study on WWOX expression in patients with Philadelphia chromosome-negative MPNs in our region. The reduction in WWOX expression might be a potential lead to a new marker in the diagnosis and pathogenesis of Philadelphia chromosomenegative MPNs.