[Molecular mechanisms of angioimmunoblastic T-cell lymphoma].

Angioimmunoblastic T-cell lymphoma (AITL) is a distinct subtype of peripheral T-cell lymphoma. The origins of AITL tumor cells were thought to be follicular helper T (TFH) cells based on the common features of these two cell types. Recent findings suggest a multistep model for the development of AITL. The immature blood cells evolve into premalignant (prelymphoma) cells by acquisition of premalignant mutations including TET2 and/or DNMT3A mutations. The premalignant cells finally develop into full-blown tumor cells by accumulation of tumor-specific RHOA mutations. Combinations of premalignant and tumor-specific mutations may induce development of AITL.