Identification of a novel fusion gene, RARA::ANKRD34C, in acute promyelocytic leukemia.

Acute promyelocytic leukemia (APL) is a specific subtype of acute myeloid leukemia that is distinguished by the chromosomal translocation t(15;17)(q24;q21), which leads to the fusion of the promyelocytic leukemia (PML) gene with the retinoic acid receptor alpha (RARA). Recently, we identified a novel fusion gene in APL, RARA::ankyrin repeat domain 34C (ANKRD34C), identified its functions by morphological, cytogenetic, molecular biological and multiplex fluorescence in situ hybridization analyses, and demonstrated the potential therapeutic effect clinically and experimentally of all-trans retinoic acid (ATRA); the findings have important implications for the diagnosis and treatment of atypical APL.

Overcoming the blood-brain barrier by using a multistage exosome delivery system to inhibit central nervous system lymphoma.

Due to the presence of blood-brain barrier (BBB), various chemotherapy drugs against B-cell lymphoma cannot be effectively transmitted into the brain, leading to poor prognosis of primary central nervous system lymphoma (PCNSL). Exosomes can cross the BBB as a bio- and immune-compatible drug carrier. In this study, we developed a novel drug delivery system, in which the exosomes (Exo) are conjugated with anti-CD22 monoclonal antibody fragments (CD22-F(ab')2) and encapsulate doxorubicin (DOX) to form CD22-F(ab')2-Exo-DOX. We showed that CD22-F(ab')2-Exo-DOX can cross BBB and deliver DOX precisely to tumor cells. The average apoptosis rate of lymphoma cells was 84.60% ±â€¯10.69%. The tumor-bearing mice treated with CD22-F(ab')2-Exo-DOX have significantly prolonged life expectancy and the enhanced anti-tumor activity. CD22-F(ab')2-Exo-DOX might be ingested by brain microvascular endothelial cells through endocytosis to cross the BBB. Therefore, targeted chemotherapy mediated by CD22-F(ab')2-Exo-DOX is a promising option for the treatment of PCNSL.