Xp11 translocation renal cell carcinoma is a rare disease diagnosed in children and adolescents in the advanced stage with an aggressive clinical course. Various gene fusions including the transcription factor E3 (TFE3) gene located on chromosome X cause the tumor. In the current issue of Cancer Biology & Therapy, Hirobe and colleagues established an Xp11 translocation renal cell carcinoma cell line from a renal tumor in a 16-year-old Japanese female. The cell line and its xenograft demonstrated definite gene fusion including TFE3. They showed strong nuclear staining for TFE3 in immunohistochemistry, TFE3 gene rearrangement in dual-color, break-apart FISH analysis and ASPL-TFE3 type 1 fusion transcripts detected by RT-PCR and direct DNA sequencing. The cover image, taken from their manuscript, shows phase-contrast light micrograph of the cell line. To learn the about the Xp11 translocation renal cell carcinoma and this cell line, read the article by Hirobe and colleagues, pp. 502-10.