Establishment and Long-Term Expansion of Small Cell Lung Cancer Patient-Derived Tumor Organoids.

Differential chemo-sensitivity of cancer cells, which is attributed to the cellular heterogeneity and phenotypic variation of cancer cells, is considered to be the main reason for tumor recurrence after chemotherapy. Here, we generated small cell lung cancer patient-derived tumor organoids and subjected them to long-term expansion with the addition of WNT3A or R-spondin1. We confirmed that the organoids have similar genetic profiles, molecular characteristics, and morphological architectures to the corresponding patient tumor tissue during and after long-term expansion. Interestingly, the cellular heterogeneity of organoids is reflected in their differential response to cisplatin or etoposide. We propose to utilize the organoids as small cell lung cancer patient avatar models that would be ideal for investigating the mechanisms underlying tumor recurrence after chemotherapy, and would ultimately help to develop personalized medicine.