Establishment and characterisation of STAM4, a novel human adamantinomatous craniopharyngioma cell line, through human telomerase reverse transcriptase ectopic expression‐mediated immortalisation.

Aims: Adamantinomatous craniopharyngioma (ACP) is a rare benign intracranial tumour that occurs in the sellar region and likely originates from the embryonic craniopharyngeal epithelium (a remnant of the ectoderm, also known as Rathke's pouch). However, progress in ACP research has been slow due to the lack of ACP cell lines. Therefore, in this study, we established an immortalised ACP cell line. Methods: Immortalised ACP cells were established from cultured primary ACP cells by the ectopic expression of human telomerase reverse transcriptase (hTERT). Primary and immortalised cells were compared and characterised by morphological examination, short tandem repeat (STR) profiling, whole exome sequencing (WES) and transcriptome sequencing. The ability of immortalised cells to form tumours was examined using an intracranial tumour formation assay in mice. Immunofluorescence staining was performed to compare the characteristics of human ACP and intracranial xenografts derived from immortalised cells. Results: A novel immortalised ACP cell line, STAM4, was successfully established in a 4‐year‐old male ACP patient. When STAM4 cells were compared with primary ACP cells in terms of morphological characteristics, genetic variants, STR profiles, biological behaviours and transcriptome differences, STAM4 cells were similar to primary ACP cells. Additionally, the STAM4 cells were able to form intracranial tumours that resemble human ACP. Conclusions: This ACP cell line may provide a cell model for further studies on the molecular mechanisms underlying the occurrence and progression of ACP and for the development of new anticancer drugs for ACP. [ABSTRACT FROM AUTHOR]