Aims: Loss of CD7 is characteristic of adult T-cell lymphoma/leukaemia (ATLL). Galectin-3 (Gal-3) is strongly induced in cultured human T lymphotropic virus-1-infected T lymphocytes, and may cause apoptosis through interaction with CD7. The aim was to investigate the clinical relevance of the Gal-3–CD7 pathway in ATLL.
Methods and results: Immunohistochemistry for Gal-3 and CD7 was performed on 22 cases of ATLL in the leukaemic phase. We found that the lymphoma cells were not necessarily Gal-3+, but Gal-3+ stromal cells could always be found. Independent of the status of Gal-3, there was an association of loss of CD7 with a worse prognosis.
Conclusions: These data suggest that, by down-regulating CD7, ATLL cells could have escaped Gal-3-induced apoptosis to run a more aggressive clinical course.