Primary myelofibrosis: current therapeutic options

Complete resolution of primary myelofibrosis in an infant with steroids and hydroxyurea

Paediatric primary myelofibrosis (PMF) is exceedingly rare and distinct compared with adult PMF. It is characterised by peripheral blood cytopenias, leucoerythroblastosis, reticulin fibrosis, extramedullary haematopoiesis and hepatosplenomegaly. In the absence of laid down diagnostic criteria, the diagnosis is largely of exclusion. Though early haematological stem cell transplant (HSCT) remains the treatment of choice, spontaneous remission or remission with steroids and/or cytoreductive agents is described in around 20% of cases of paediatric PMF. Moreover, HSCT in paediatric PMF is associated with high mortality (30%-45%). Therefore, it may be prudent to consider a trial of steroids and/or cytoreductive agents in all transfusion-dependent paediatric PMF while considering HSCT and ongoing bone marrow donor search. We describe one such infant with PMF who had complete remission of clinical and haematological parameters with a combination therapy of steroids and hydroxyurea.

Advances in management of primary myelofibrosis and polycythaemia vera: Implications in clinical practice

Primary myelofibrosis (PMF) and polycythaemia vera (PV) are rare BCR-ABL1-negative myeloproliferative neoplasms, associated with an increased risk of thrombosis, haemorrhagic complications and progression to fibrosis or leukaemia or fibrosis for PV. Both diseases are characterised by biological and clinical heterogeneity, leading to great variability in their management in routine clinical practice. In this review, we present an updated overview of the diagnosis, prognosis and treatment of PMF and PV, and we discuss how our multidisciplinary expert group based across France translates this evidence-based knowledge into routine clinical practice.

Could cytokine release syndrome induce acute myelofibrosis in CD19 chimeric antigen receptor T cells therapy?

CAR-T cells therapy can give rise to most common and concerning two side effects – cytokine release syndrome (CRS) and neurotoxicity. But in our CD19 CAR-T cells therapy clinical trial, we observed 1 out of 17 patients with B-cell acute lymphoblastic leukemia (B-ALL) developed acute myelofibrosis(AMF) after grade IV CRS post to the CD19 CAR-T cells therapy. This finding suggests that the CAR-T cells therapy may have rare and serious AMF, which we should pay important attention to.

Trial registration:NCT02968472. Registered 18 November 2016 – Retrospectively registered, https://clinicaltrials.gov/ct2/show/NCT02968472

Sclt1 deficiency causes cystic kidney by activating ERK and STAT3 signaling

Ciliopathies form a group of inherited disorders sharing several clinical manifestations because of abnormal cilia formation or function, and few treatments have been successful against these disorders. Here, we report a mouse model with mutated Sclt1 gene, which encodes a centriole distal appendage protein important for ciliogenesis. Sodium channel and clathrin linker 1 (SCLT1) mutations were associated with the oral-facial-digital syndrome (OFD), an autosomal recessive ciliopathy. The Sclt1-/- mice exhibit typical ciliopathy phenotypes, including cystic kidney, cleft palate and polydactyly. Sclt1-loss decreases the number of cilia in kidney; increases proliferation and apoptosis of renal tubule epithelial cells; elevates protein kinase A, extracellular signal-regulated kinases, SMAD and signal transducer and activator of transcription 3 (STAT3) pathways; and enhances pro-inflammation and pro-fibrosis pathways with disease progression. Embryonic kidney cyst formation of Sclt1-/- mice was effectively reduced by an anti-STAT3 treatment using pyrimethamine. Overall, we reported a new mouse model for the OFD; and our data suggest that STAT3 inhibition may be a promising treatment for SCLT1-associated cystic kidney.

Steroid-resistant autoimmune myelofibrosis in a patient with autoimmune hepatitis and Evans syndrome complicated with increased expression of TGF-β in the bone marrow: a case report

We here report a 47-year-old female with autoimmune myelofibrosis (AIMF) associated with liver damage caused by autoimmune hepatitis and Evans syndrome. Bone marrow biopsy revealed hypocellular marrow with grade 2 reticulin fibrosis and increased levels of B lymphocytes (CD20⁺), T lymphocytes (CD3⁺, CD8⁺), and plasma cells (CD138⁺). Immunohistochemical analysis revealed increased expression of transforming growth factor-β (TGF-β) in infiltrating lymphocytes and macrophages in the bone marrow. She was initially treated with oral prednisolone (PSL) for 2 months, which had a limited effect. However, after treatment with rituximab, the patient's pancytopenia showed improvement, allowing us to rapidly reduce the PSL dosage. The present case suggests the possibility that increased expression of TGF-β in infiltrating lymphocytes and macrophages of bone marrow may contribute to the pathogenesis of AIMF. Prednisolone combined with rituximab may thus be an effective option for steroid-refractory cases.