TCF3 and ID3 Regulate TSPAN32 Expression in Burkitt Lymphoma.

Abstract

Burkitt lymphoma (BL) is an aggressive non-Hodgkin B-cell lymphoma characterised by chromosomal translocations involving the MYC gene, leading to its overexpression and driving uncontrolled proliferation. BL is categorised into endemic, sporadic, and immunodeficiency-associated subtypes, each with distinct clinical and epidemiological features. TSPAN32, a member of the tetraspanin family, plays a key role in B cell development and immune regulation. In this study, we investigated the regulation of TSPAN32 expression in BL subtypes. Our results show that TSPAN32 expression is significantly downregulated in endemic, sporadic, and HIV-associated BL. Notably, this downregulation is independent of Epstein-Barr virus (EBV) infection, as no significant differences in TSPAN32 expression were observed between EBV-positive and EBV-negative BL clones. Functional studies revealed that overexpression of a wild-type ID3 gene, a known repressor of TCF3, and knockdown of TCF3, both led to a significant upregulation of TSPAN32, particularly in BL41 and Daudi cells, which harbour ID3 mutations. Supporting this, ChIP-seq analysis identified TCF3 binding peaks on the TSPAN32 gene, providing mechanistic evidence of its regulation by TCF3. These findings shed light on the complex transcriptional network regulating TSPAN32 and its dysregulation in BL. Overall, our study suggests that TSPAN32 may serve as both a biomarker and a potential therapeutic target for this disease.