%0 Journal Article %T Transforming tumoroids derived from ALK-positive pulmonary adenocarcinoma to squamous cell carcinoma in vivo. %A Yokota E %A Iwai M %A Ishida Y %A Yukawa T %A Matsubara M %A Naomoto Y %A Fujiwara H %A Monobe Y %A Haisa M %A Takigawa N %A Fukazawa T %A Yamatsuji T %J Hum Cell %V 37 %N 4 %D 2024 Jul 3 %M 38829559 %F 4.374 %R 10.1007/s13577-024-01085-8 %X Approximately 3-5% of non-small cell lung cancers (NSCLC) harbor ALK fusion genes and may be responsive to anaplastic lymphoma kinase (ALK) tyrosine kinase inhibitors. There are only a few reports on cell lines with EML4-ALK variant 3 (v3) and tumoroids that can be subject to long-term culture (> 3 months). In this study, we established tumoroids (PDT-LUAD#119) from a patient with lung cancer harboring EML4-ALK that could be cultured for 12 months. Whole-exome sequencing and RNA sequencing analyses revealed TP53 mutations and an EML4-ALK v3 mutation. PDT-LUAD#119 lung tumoroids were sensitive to the ALK tyrosine kinase inhibitors (ALK TKIs) crizotinib, alectinib, entrectinib, and lorlatinib, similar to NCI-H3122 cells harboring EML4-ALK variant 1 (v1). Unexpectedly, clear squamous cell carcinoma and solid adenocarcinoma were observed in xenografts from PDT-LUAD#119 lung tumoroids, indicating adenosquamous carcinoma. Immunostaining revealed that the squamous cell carcinoma was ALK positive, suggesting a squamous transformation of the adenocarcinoma. Besides providing a novel cancer model to support basic research on ALK-positive lung cancer, PDT-LUAD#119 lung tumoroids will help elucidate the pathogenesis of adenosquamous carcinoma.