Gene expression profiling of CTCL patient-derived cell lines after GTSF1 knockdown

In CTCL, the ectopic expression of Gametocyte Specific Factor 1 (GTSF1) has emerged as a potential prognostic biomarker. High expression of GTSF1 has been associated with a worse overall prognosis for patients. However, the contribution of GTSF1 to CTCL carcinogenesis remains unknown. We performed a shRNA mediated silencing of GTSF1 in three cell lines representing the most common variants of CTCL: Mac2A, representative of primary cutaneous Anaplastic Large Cell Lymphoma; MyLa 2000, representative of Mycosis Fungoides; and SZ4, representative of Sézary Syndrome. The three cell lines showed different gene expression profiles, signaling the different clinical behaviors of each variant. In Mac2A, silencing of GTSF1 in CTCL led to T cell activation and production of IFNγ and TNFα. This suugests that GTSF1 contributes to carcinogenesis by partially modifying the effector-memory phenotype of the malignant T cells.