RESUMEN
ABSTRACT: SRY-related HMG-box gene 11 (SOX11) is a transcription factor overexpressed in mantle cell lymphoma (MCL), a subset of Burkitt lymphomas (BL) and precursor lymphoid cell neoplasms but is absent in normal B cells and other B-cell lymphomas. SOX11 has an oncogenic role in MCL but its contribution to BL pathogenesis remains uncertain. Here, we observed that the presence of Epstein-Barr virus (EBV) and SOX11 expression were mutually exclusive in BL. SOX11 expression in EBV-negative (EVB-) BL was associated with an IGâ·MYC translocation generated by aberrant class switch recombination, whereas in EBV-negative (EBV-)/SOX11-negative (SOX11-) tumors the IGâ·MYC translocation was mediated by mistaken somatic hypermutations. Interestingly, EBV- SOX11-expressing BL showed higher frequency of SMARCA4 and ID3 mutations than EBV-/SOX11- cases. By RNA sequencing, we identified a SOX11-associated gene expression profile, with functional annotations showing partial overlap with the SOX11 transcriptional program of MCL. Contrary to MCL, no differences on cell migration or B-cell receptor signaling were found between SOX11- and SOX11-positive (SOX11+) BL cells. However, SOX11+ BL showed higher adhesion to vascular cell adhesion molecule 1 (VCAM-1) than SOX11- BL cell lines. Here, we demonstrate that EBV- BL comprises 2 subsets of cases based on SOX11 expression. The mutual exclusion of SOX11 and EBV, and the association of SOX11 with a specific genetic landscape suggest a role of SOX11 in the early pathogenesis of BL.
Asunto(s)
Linfoma de Burkitt , Herpesvirus Humano 4 , Factores de Transcripción SOXC , Humanos , Linfoma de Burkitt/genética , Linfoma de Burkitt/virología , Linfoma de Burkitt/metabolismo , Linfoma de Burkitt/patología , Factores de Transcripción SOXC/genética , Factores de Transcripción SOXC/metabolismo , Herpesvirus Humano 4/genética , Regulación Neoplásica de la Expresión Génica , Infecciones por Virus de Epstein-Barr/genética , Infecciones por Virus de Epstein-Barr/complicaciones , Infecciones por Virus de Epstein-Barr/virología , Mutación , ADN Helicasas/genética , ADN Helicasas/metabolismo , Translocación Genética , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Masculino , Proteínas Inhibidoras de la Diferenciación/genética , Proteínas Inhibidoras de la Diferenciación/metabolismo , Proteínas NuclearesRESUMEN
Mantle cell lymphoma (MCL) is an incurable B-cell neoplasm characterized by an aggressive behavior, short responses to conventional therapies and SOX11 overexpression, which is associated with aggressive disease features and inferior clinical outcome of patients. Oxidative stress is known to induce tumorigenesis and tumor progression, whereas high expression levels of antioxidant genes have been associated with chemoresistance in different cancers. However, the role of oxidative stress in MCL pathogenesis and the involvement of SOX11 regulating redox homeostasis in MCL cells are largely unknown. Here, by integrating gene set enrichment analysis of two independent series of MCL, we observed that SOX11+ MCL had higher reactive oxygen species (ROS) levels compared to SOX11- MCL primary tumors and increased expression of Peredoxine2 (PRDX2), which upregulation significantly correlated with SOX11 overexpression, higher ROS production and worse overall survival of patients. SOX11 knockout (SOX11KO) significantly reduced PRDX2 expression, and SOX11KO and PRDX2 knockdown (PRDX2KD) had increased ROS levels and ROS-mediated tumor cell death upon treatment with drugs, compared to control MCL cell lines. Our results suggest an aberrant redox homeostasis associated with chemoresistance in aggressive MCL through SOX11-mediated PRDX2 upregulation, highlighting PRDX2 as promising target for new therapeutic strategies to overcome chemoresistance in aggressive MCLs.