Expression and role of the receptor tyrosine kinase-like orphan receptor2 (ROR2) in small cell lung cancer

Heterogeneity of ROR2 was observed in the tumor tissues form patient-derived xenograft (PDX) model of SCLC, in which the cells with high ROR2 expression (ROR2high cell) and those without ROR2 expression (ROR2low cell) were gained and subjected to RNA sequence analysis. Cell proliferation activity was suppressed in ROR2 KO SBC3 cells in vitro and in vivo. Comparison of the downregulated DEG in the ROR2 KO SBC3 cells and the upregulated DEG in ROR2high cells in the PDX model revealed 135 common genes. After Metascape analysis of these genes, we focus on Aurora kinases. These results suggest that ROR2 could regulate cell cycle through AURKA and/or AURKB. This study clarrifies the function of ROR2 in SCLC with heterogeneous expression condition. Examination of RNA-sequencing of 2 conditions: 1) ROR2high and ROR2low cells sorted from small cell lung cancer xenograft. 2) ROR2 knockout or control SBC-3 cells.